MDedge Emergency Medicine

New data present further evidence that SARS-CoV-2 infection can settle in the gastrointestinal tract and that it can persist long after the infection has cleared the lungs.

Infection of the GI tract may figure prominently in long COVID, the study authors suggested.

Led by Aravind Natarajan, PhD, with the departments of genetics and medicine at Stanford (Calif.) University, they analyzed fecal RNA shedding up to 10 months after a COVID-19 diagnosis in 673 stool samples from 113 patients with mild to moderate disease.

They found that, in the week after diagnosis, COVID RNA remnants were present in the stool of approximately half (49.2%) of the patients. Seven months later, about 4% of them shed fecal viral RNA.

The authors noted that there was no ongoing SARS-CoV-2 RNA shedding in respiratory samples of patients at the 4-month mark.

Using self-reported symptoms regularly collected by questionnaire, they also found a correlation of long-term fecal shedding of SARS-CoV-2 RNA with abdominal pain, nausea, and vomiting.

The findings were published online in Med.
 

Implications of long-term viral shedding

Previous studies have found SARS-CoV-2 RNA in respiratory and fecal samples and have documented viral replication in lung and intestinal tissue. But before the current study, little had been known about long-term shedding, especially in those who have mild COVID. Most studies of viral shedding have been with severe COVID cases.

The authors noted that most studies of this kind are cross-sectional. The few other longitudinal studies have focused on early time points just after diagnosis.

Senior author Ami S. Bhatt, MD, associate professor in the departments of medicine and hematology at Stanford University, said in an interview that, though the viral genetic material in the feces lingers, on the basis of available evidence, it is highly unlikely to be contagious in most cases.

She said that understanding the dynamics of fecal shedding of SARS-CoV-2 genetic material will help interpret wastewater-based studies that are trying to determine population prevalence of the virus.

“While we don’t know the exact clinical importance of the longer-term shedding of SARS-CoV-2 in individuals with COVID-19, some have speculated that those who have long-term shedding of SARS-CoV-2 may have ongoing infections that might benefit from treatment,” she said.

“Our data support the idea that the long-term GI-related symptoms in some people might be the consequence of an ongoing infection in the GI tract, even after the respiratory infection has cleared,” Dr. Bhatt said.

“Alternatively, the presence of ongoing viral genetic material in the gut might be a trigger for the immune system to continually be active against the virus, and our immune system reaction may be the reason for long COVID–type symptoms,” she added. “This area is ripe for additional studies.”

Dr. Bhatt and colleagues will continue studying viral shedding in fecal samples as part of the nationwide RECOVER Initiative.

When reached for comment, David A. Johnson, MD, professor of medicine and chief of gastroenterology, Eastern Virginia Medical School, Norfolk, said in an interview that previous studies have indicated that the virus may be detected in the stool for a month or more and for about 2 weeks on average. Whether the virus is infectious has been in question.

But it’s not so much that the virus is infectious in the GI tract and causing symptoms, he said. Rather, there are biomic changes related to COVID, including a loss of diversity in the gut bacteria, which disrupts the balance.

“This may actually in some way predispose some patients to impaired clearance of their symptoms,” Dr. Johnson explained. “There seems to be a growing recognition that this entity called long-haul COVID may be related to specific bacterial disruptions, and the more rapidly you can resolve these disruptions, the less likely you are to continue with long-haul symptoms.”

He said that, among people who have mild COVID, the virus typically clears and gut bacteria return to normal. With severe or persistent illness, gut dysbiosis persists, he said.

“People need to be aware that the GI tract is involved in a sizable percent of patients with COVID,” Dr. Johnson said. “The GI-tract testing may reflect that the virus is there, but persistence of the detectable test positivity is very unlikely to reflect active virus.”

The authors noted that they collected only six samples from the participants over the 10-month study period.

“Follow-up studies with more frequent sampling, especially in the first 2 months after diagnosis, may help build a more nuanced model of decline of fecal viral RNA concentration over time,” they wrote.

The study was supported by a Stanford ChemH-IMA grant, fellowships from the AACR and the National Science Foundation, and the National Institutes of Health. The authors and Dr. Johnson reported no relevant financial relationships. Dr. Johnson is a regular contributor to this news organization.

A version of this article first appeared on Medscape.com.

New data present further evidence that SARS-CoV-2 infection can settle in the gastrointestinal tract and that it can persist long after the infection has cleared the lungs.

Infection of the GI tract may figure prominently in long COVID, the study authors suggested.

Led by Aravind Natarajan, PhD, with the departments of genetics and medicine at Stanford (Calif.) University, they analyzed fecal RNA shedding up to 10 months after a COVID-19 diagnosis in 673 stool samples from 113 patients with mild to moderate disease.

They found that, in the week after diagnosis, COVID RNA remnants were present in the stool of approximately half (49.2%) of the patients. Seven months later, about 4% of them shed fecal viral RNA.

The authors noted that there was no ongoing SARS-CoV-2 RNA shedding in respiratory samples of patients at the 4-month mark.

Using self-reported symptoms regularly collected by questionnaire, they also found a correlation of long-term fecal shedding of SARS-CoV-2 RNA with abdominal pain, nausea, and vomiting.

The findings were published online in Med.
 

Implications of long-term viral shedding

Previous studies have found SARS-CoV-2 RNA in respiratory and fecal samples and have documented viral replication in lung and intestinal tissue. But before the current study, little had been known about long-term shedding, especially in those who have mild COVID. Most studies of viral shedding have been with severe COVID cases.

The authors noted that most studies of this kind are cross-sectional. The few other longitudinal studies have focused on early time points just after diagnosis.

Senior author Ami S. Bhatt, MD, associate professor in the departments of medicine and hematology at Stanford University, said in an interview that, though the viral genetic material in the feces lingers, on the basis of available evidence, it is highly unlikely to be contagious in most cases.

She said that understanding the dynamics of fecal shedding of SARS-CoV-2 genetic material will help interpret wastewater-based studies that are trying to determine population prevalence of the virus.

“While we don’t know the exact clinical importance of the longer-term shedding of SARS-CoV-2 in individuals with COVID-19, some have speculated that those who have long-term shedding of SARS-CoV-2 may have ongoing infections that might benefit from treatment,” she said.

“Our data support the idea that the long-term GI-related symptoms in some people might be the consequence of an ongoing infection in the GI tract, even after the respiratory infection has cleared,” Dr. Bhatt said.

“Alternatively, the presence of ongoing viral genetic material in the gut might be a trigger for the immune system to continually be active against the virus, and our immune system reaction may be the reason for long COVID–type symptoms,” she added. “This area is ripe for additional studies.”

Dr. Bhatt and colleagues will continue studying viral shedding in fecal samples as part of the nationwide RECOVER Initiative.

When reached for comment, David A. Johnson, MD, professor of medicine and chief of gastroenterology, Eastern Virginia Medical School, Norfolk, said in an interview that previous studies have indicated that the virus may be detected in the stool for a month or more and for about 2 weeks on average. Whether the virus is infectious has been in question.

But it’s not so much that the virus is infectious in the GI tract and causing symptoms, he said. Rather, there are biomic changes related to COVID, including a loss of diversity in the gut bacteria, which disrupts the balance.

“This may actually in some way predispose some patients to impaired clearance of their symptoms,” Dr. Johnson explained. “There seems to be a growing recognition that this entity called long-haul COVID may be related to specific bacterial disruptions, and the more rapidly you can resolve these disruptions, the less likely you are to continue with long-haul symptoms.”

He said that, among people who have mild COVID, the virus typically clears and gut bacteria return to normal. With severe or persistent illness, gut dysbiosis persists, he said.

“People need to be aware that the GI tract is involved in a sizable percent of patients with COVID,” Dr. Johnson said. “The GI-tract testing may reflect that the virus is there, but persistence of the detectable test positivity is very unlikely to reflect active virus.”

The authors noted that they collected only six samples from the participants over the 10-month study period.

“Follow-up studies with more frequent sampling, especially in the first 2 months after diagnosis, may help build a more nuanced model of decline of fecal viral RNA concentration over time,” they wrote.

The study was supported by a Stanford ChemH-IMA grant, fellowships from the AACR and the National Science Foundation, and the National Institutes of Health. The authors and Dr. Johnson reported no relevant financial relationships. Dr. Johnson is a regular contributor to this news organization.

A version of this article first appeared on Medscape.com.

New data present further evidence that SARS-CoV-2 infection can settle in the gastrointestinal tract and that it can persist long after the infection has cleared the lungs.

Infection of the GI tract may figure prominently in long COVID, the study authors suggested.

Led by Aravind Natarajan, PhD, with the departments of genetics and medicine at Stanford (Calif.) University, they analyzed fecal RNA shedding up to 10 months after a COVID-19 diagnosis in 673 stool samples from 113 patients with mild to moderate disease.

They found that, in the week after diagnosis, COVID RNA remnants were present in the stool of approximately half (49.2%) of the patients. Seven months later, about 4% of them shed fecal viral RNA.

The authors noted that there was no ongoing SARS-CoV-2 RNA shedding in respiratory samples of patients at the 4-month mark.

Using self-reported symptoms regularly collected by questionnaire, they also found a correlation of long-term fecal shedding of SARS-CoV-2 RNA with abdominal pain, nausea, and vomiting.

The findings were published online in Med.
 

Implications of long-term viral shedding

Previous studies have found SARS-CoV-2 RNA in respiratory and fecal samples and have documented viral replication in lung and intestinal tissue. But before the current study, little had been known about long-term shedding, especially in those who have mild COVID. Most studies of viral shedding have been with severe COVID cases.

The authors noted that most studies of this kind are cross-sectional. The few other longitudinal studies have focused on early time points just after diagnosis.

Senior author Ami S. Bhatt, MD, associate professor in the departments of medicine and hematology at Stanford University, said in an interview that, though the viral genetic material in the feces lingers, on the basis of available evidence, it is highly unlikely to be contagious in most cases.

She said that understanding the dynamics of fecal shedding of SARS-CoV-2 genetic material will help interpret wastewater-based studies that are trying to determine population prevalence of the virus.

“While we don’t know the exact clinical importance of the longer-term shedding of SARS-CoV-2 in individuals with COVID-19, some have speculated that those who have long-term shedding of SARS-CoV-2 may have ongoing infections that might benefit from treatment,” she said.

“Our data support the idea that the long-term GI-related symptoms in some people might be the consequence of an ongoing infection in the GI tract, even after the respiratory infection has cleared,” Dr. Bhatt said.

“Alternatively, the presence of ongoing viral genetic material in the gut might be a trigger for the immune system to continually be active against the virus, and our immune system reaction may be the reason for long COVID–type symptoms,” she added. “This area is ripe for additional studies.”

Dr. Bhatt and colleagues will continue studying viral shedding in fecal samples as part of the nationwide RECOVER Initiative.

When reached for comment, David A. Johnson, MD, professor of medicine and chief of gastroenterology, Eastern Virginia Medical School, Norfolk, said in an interview that previous studies have indicated that the virus may be detected in the stool for a month or more and for about 2 weeks on average. Whether the virus is infectious has been in question.

But it’s not so much that the virus is infectious in the GI tract and causing symptoms, he said. Rather, there are biomic changes related to COVID, including a loss of diversity in the gut bacteria, which disrupts the balance.

“This may actually in some way predispose some patients to impaired clearance of their symptoms,” Dr. Johnson explained. “There seems to be a growing recognition that this entity called long-haul COVID may be related to specific bacterial disruptions, and the more rapidly you can resolve these disruptions, the less likely you are to continue with long-haul symptoms.”

He said that, among people who have mild COVID, the virus typically clears and gut bacteria return to normal. With severe or persistent illness, gut dysbiosis persists, he said.

“People need to be aware that the GI tract is involved in a sizable percent of patients with COVID,” Dr. Johnson said. “The GI-tract testing may reflect that the virus is there, but persistence of the detectable test positivity is very unlikely to reflect active virus.”

The authors noted that they collected only six samples from the participants over the 10-month study period.

“Follow-up studies with more frequent sampling, especially in the first 2 months after diagnosis, may help build a more nuanced model of decline of fecal viral RNA concentration over time,” they wrote.

The study was supported by a Stanford ChemH-IMA grant, fellowships from the AACR and the National Science Foundation, and the National Institutes of Health. The authors and Dr. Johnson reported no relevant financial relationships. Dr. Johnson is a regular contributor to this news organization.

A version of this article first appeared on Medscape.com.

The current sustained increase in COVID-19 has brought the total number of cases in children to over 13 million since the start of the pandemic, according to the American Academy of Pediatrics and the Children’s Hospital Association.

The latest weekly count – 62,467 reported for the week ending May 5 – was 17.4% higher than the previous week and marks four consecutive increases since early April, when cases dropped to their lowest point since last summer. The cumulative number of cases in children is 13,052,988, which accounts for 19.0% of all cases reported in the United States, the AAP and CHA said in their weekly COVID-19 report.

Other measures of incidence show the same steady rise. The rate of new admissions of children aged 0-17 with confirmed COVID-19, which had dipped as low as 0.13 per 100,000 population on April 11, was up to 0.19 per 100,000 on May 6, and the 7-day average for total admissions was 136 per day for May 1-7, compared with 118 for the last week of April, according to the Centers for Disease Control and Prevention.

At the state level, new admission rates for May 6 show wide variation, even regionally. Rhode Island came in with a 0.00 per 100,000 on that day, while Vermont recorded 0.88 admissions per 100,000, the highest of any state and lower only than the District of Columbia’s 1.23 per 100,000. Connecticut (0.45) and Massachusetts (0.33) also were in the highest group (see map), while Maine was in the lowest, CDC data show.

Nationally, emergency department visits also have been rising over the last month or so. Children aged 0-11 years, who were down to a 7-day average of 0.5% of ED visits with diagnosed COVID-19 in early April, saw that number rise to 1.4% on May 5. Children aged 12-15 years went from a rate of 0.3% in late March to the current 1.2%, as did 16- to 17-year-olds, the CDC said on its COVID Data Tracker.

The vaccination effort, meanwhile, continues to lose steam, at least among children who are currently eligible. Initial vaccinations in those aged 5-11 slipped to their lowest-ever 1-week total, 47,000 for April 28 to May 4, while children aged 16-17 continued a long-term slide that has the weekly count down to just 29,000, the AAP said in its weekly vaccination report.

Here’s how those latest recipients changed the populations of vaccinated children in the last week: 35.4% of all 5- to 11-year-olds had received at least one dose as of May 4, compared with 35.3% on April 27, with increases from 67.4% to 67.5% for 12- to 15-year-olds and 72.7% to 72.8% among those aged 16-17, the CDC reported.
 

The current sustained increase in COVID-19 has brought the total number of cases in children to over 13 million since the start of the pandemic, according to the American Academy of Pediatrics and the Children’s Hospital Association.

The latest weekly count – 62,467 reported for the week ending May 5 – was 17.4% higher than the previous week and marks four consecutive increases since early April, when cases dropped to their lowest point since last summer. The cumulative number of cases in children is 13,052,988, which accounts for 19.0% of all cases reported in the United States, the AAP and CHA said in their weekly COVID-19 report.

Other measures of incidence show the same steady rise. The rate of new admissions of children aged 0-17 with confirmed COVID-19, which had dipped as low as 0.13 per 100,000 population on April 11, was up to 0.19 per 100,000 on May 6, and the 7-day average for total admissions was 136 per day for May 1-7, compared with 118 for the last week of April, according to the Centers for Disease Control and Prevention.

At the state level, new admission rates for May 6 show wide variation, even regionally. Rhode Island came in with a 0.00 per 100,000 on that day, while Vermont recorded 0.88 admissions per 100,000, the highest of any state and lower only than the District of Columbia’s 1.23 per 100,000. Connecticut (0.45) and Massachusetts (0.33) also were in the highest group (see map), while Maine was in the lowest, CDC data show.

Nationally, emergency department visits also have been rising over the last month or so. Children aged 0-11 years, who were down to a 7-day average of 0.5% of ED visits with diagnosed COVID-19 in early April, saw that number rise to 1.4% on May 5. Children aged 12-15 years went from a rate of 0.3% in late March to the current 1.2%, as did 16- to 17-year-olds, the CDC said on its COVID Data Tracker.

The vaccination effort, meanwhile, continues to lose steam, at least among children who are currently eligible. Initial vaccinations in those aged 5-11 slipped to their lowest-ever 1-week total, 47,000 for April 28 to May 4, while children aged 16-17 continued a long-term slide that has the weekly count down to just 29,000, the AAP said in its weekly vaccination report.

Here’s how those latest recipients changed the populations of vaccinated children in the last week: 35.4% of all 5- to 11-year-olds had received at least one dose as of May 4, compared with 35.3% on April 27, with increases from 67.4% to 67.5% for 12- to 15-year-olds and 72.7% to 72.8% among those aged 16-17, the CDC reported.
 

The current sustained increase in COVID-19 has brought the total number of cases in children to over 13 million since the start of the pandemic, according to the American Academy of Pediatrics and the Children’s Hospital Association.

The latest weekly count – 62,467 reported for the week ending May 5 – was 17.4% higher than the previous week and marks four consecutive increases since early April, when cases dropped to their lowest point since last summer. The cumulative number of cases in children is 13,052,988, which accounts for 19.0% of all cases reported in the United States, the AAP and CHA said in their weekly COVID-19 report.

Other measures of incidence show the same steady rise. The rate of new admissions of children aged 0-17 with confirmed COVID-19, which had dipped as low as 0.13 per 100,000 population on April 11, was up to 0.19 per 100,000 on May 6, and the 7-day average for total admissions was 136 per day for May 1-7, compared with 118 for the last week of April, according to the Centers for Disease Control and Prevention.

At the state level, new admission rates for May 6 show wide variation, even regionally. Rhode Island came in with a 0.00 per 100,000 on that day, while Vermont recorded 0.88 admissions per 100,000, the highest of any state and lower only than the District of Columbia’s 1.23 per 100,000. Connecticut (0.45) and Massachusetts (0.33) also were in the highest group (see map), while Maine was in the lowest, CDC data show.

Nationally, emergency department visits also have been rising over the last month or so. Children aged 0-11 years, who were down to a 7-day average of 0.5% of ED visits with diagnosed COVID-19 in early April, saw that number rise to 1.4% on May 5. Children aged 12-15 years went from a rate of 0.3% in late March to the current 1.2%, as did 16- to 17-year-olds, the CDC said on its COVID Data Tracker.

The vaccination effort, meanwhile, continues to lose steam, at least among children who are currently eligible. Initial vaccinations in those aged 5-11 slipped to their lowest-ever 1-week total, 47,000 for April 28 to May 4, while children aged 16-17 continued a long-term slide that has the weekly count down to just 29,000, the AAP said in its weekly vaccination report.

Here’s how those latest recipients changed the populations of vaccinated children in the last week: 35.4% of all 5- to 11-year-olds had received at least one dose as of May 4, compared with 35.3% on April 27, with increases from 67.4% to 67.5% for 12- to 15-year-olds and 72.7% to 72.8% among those aged 16-17, the CDC reported.
 

People who are not vaccinated against a respiratory virus such as SARS-CoV-2 present a disproportionate infectious risk to those who are vaccinated, according to a mathematical modeling study.

The study, which simulated patterns of infection among vaccinated and unvaccinated populations, showed that, as the populations mixed less, attack rates decreased among vaccinated people (from 15% to 10%) and increased among unvaccinated people (from 62% to 79%). The unvaccinated increasingly became the source of infection, however.

“When the vaccinated and unvaccinated mix, indirect protection is conferred upon the unvaccinated by the buffering effect of vaccinated individuals, and by contrast, risk in the vaccinated goes up,” lead author David Fisman, MD, professor of epidemiology at the University of Toronto, told this news organization.

As the groups mix less and less, the size of the epidemic increases among the unvaccinated and decreases among the vaccinated. “But the impact of the unvaccinated on risk in the vaccinated is disproportionate to the numbers of contacts between the two groups,” said Dr. Fisman.

The study was published online in the Canadian Medical Association Journal.


 

Relative contributions to risk

The researchers used a model of a respiratory viral disease “similar to SARS-CoV-2 infection with Delta variant.” They included reproduction values to capture the dynamics of the Omicron variant, which was emerging at the time. In the study, vaccines ranged in effectiveness from 40% to 80%. The study incorporated various levels of mixing between a partially vaccinated and an unvaccinated population. The mixing ranged from random mixing to like-with-like mixing (“assortativity”). There were three possible “compartments” of people in the model: those considered susceptible to infection, those considered infected and infectious, and those considered immune because of recovery.

The model showed that, as mixing between the vaccinated and the unvaccinated populations increased, case numbers rose, “with cases in the unvaccinated subpopulation accounting for a substantial proportion of infections.” However, as mixing between the populations decreased, the final attack rate decreased among vaccinated people, but the relative “contribution of risk to vaccinated people caused by infection acquired from contact with unvaccinated people ... increased.”

When the vaccination rate was increased in the model, case numbers among the vaccinated declined “as expected, owing to indirect protective effects,” the researchers noted. But this also “further increased the relative contribution to risk in vaccinated people by those who were unvaccinated.”
 

Self-regarding risk?

The findings show that “choices made by people who forgo vaccination contribute disproportionately to risk among those who do get vaccinated,” the researchers wrote. “Although risk associated with avoiding vaccination during a virulent pandemic accrues chiefly to those who are unvaccinated, the choice of some individuals to refuse vaccination is likely to affect the health and safety of vaccinated people in a manner disproportionate to the fraction of unvaccinated people in the population.”

The fact that like-with-like mixing cannot mitigate the risk to vaccinated people “undermines the assertion that vaccine choice is best left to the individual and supports strong public actions aimed at enhancing vaccine uptake and limiting access to public spaces for unvaccinated people,” they wrote.
 

Mandates and passports

“Our model provides support for vaccine mandates and passports during epidemics, such that vaccination is required for people to take part in nonessential activities,” said Dr. Fisman. The choice to not be vaccinated against COVID-19 should not be considered “self-regarding,” he added. “Risk is self-regarding when it only impacts the person engaging in the activity. Something like smoking cigarettes (alone, without others around) creates a lot of risk over time, but if nobody is breathing your secondhand smoke, you’re only creating risk for yourself. By contrast, we regulate, in Ontario, your right to smoke in public indoor spaces such as restaurants, because once other people are around, the risk isn’t self-regarding anymore. You’re creating risk for others.”

The authors also noted that the risks created by the unvaccinated extend beyond those of infection by “creating a risk that those around them may not be able to obtain the care they need.” They recommended that considerations of equity and justice for people who do choose to be vaccinated, as well as those who choose not to be, need to be included in formulating vaccination policy.
 

Illuminating the discussion

Asked to comment on the study, Matthew Oughton, MD, assistant professor of medicine at McGill University, Montreal, said: “It is easy to dismiss a mathematical model as a series of assumptions that leads to an implausible conclusion. ... However, they can serve to illustrate and, to an extent, quantify the results of complex interactions, and this study does just that.” Dr. Oughton was not involved in the research.

During the past 2 years, the scientific press and the general press have often discussed the individual and collective effects of disease-prevention methods, including nonpharmaceutical interventions. “Models like this can help illuminate those discussions by highlighting important consequences of preventive measures,” said Dr. Oughton, who also works in the division of infectious diseases at the Jewish General Hospital, Montreal.

It’s worth noting that the authors modeled vaccine effectiveness against all infection, “rather than the generally greater and more durable effects we have seen for vaccines in prevention of severe infection,” said Dr. Oughton. He added that the authors did not include the effect of vaccination in reducing forward transmission. “Inclusion of this effect would presumably have reduced overall infectious burden in mixed populations and increased the difference between groups at lower levels of mixing between populations.”

The research was supported by a grant from the Canadian Institutes of Health Research. Dr. Fisman has served on advisory boards related to influenza and SARS-CoV-2 vaccines for Seqirus, Pfizer, AstraZeneca, and Sanofi-Pasteur Vaccines and has served as a legal expert on issues related to COVID-19 epidemiology for the Elementary Teachers Federation of Ontario and the Registered Nurses Association of Ontario. Dr. Oughton disclosed no relevant financial relationships.

A version of this article first appeared on Medscape.com.

People who are not vaccinated against a respiratory virus such as SARS-CoV-2 present a disproportionate infectious risk to those who are vaccinated, according to a mathematical modeling study.

The study, which simulated patterns of infection among vaccinated and unvaccinated populations, showed that, as the populations mixed less, attack rates decreased among vaccinated people (from 15% to 10%) and increased among unvaccinated people (from 62% to 79%). The unvaccinated increasingly became the source of infection, however.

“When the vaccinated and unvaccinated mix, indirect protection is conferred upon the unvaccinated by the buffering effect of vaccinated individuals, and by contrast, risk in the vaccinated goes up,” lead author David Fisman, MD, professor of epidemiology at the University of Toronto, told this news organization.

As the groups mix less and less, the size of the epidemic increases among the unvaccinated and decreases among the vaccinated. “But the impact of the unvaccinated on risk in the vaccinated is disproportionate to the numbers of contacts between the two groups,” said Dr. Fisman.

The study was published online in the Canadian Medical Association Journal.


 

Relative contributions to risk

The researchers used a model of a respiratory viral disease “similar to SARS-CoV-2 infection with Delta variant.” They included reproduction values to capture the dynamics of the Omicron variant, which was emerging at the time. In the study, vaccines ranged in effectiveness from 40% to 80%. The study incorporated various levels of mixing between a partially vaccinated and an unvaccinated population. The mixing ranged from random mixing to like-with-like mixing (“assortativity”). There were three possible “compartments” of people in the model: those considered susceptible to infection, those considered infected and infectious, and those considered immune because of recovery.

The model showed that, as mixing between the vaccinated and the unvaccinated populations increased, case numbers rose, “with cases in the unvaccinated subpopulation accounting for a substantial proportion of infections.” However, as mixing between the populations decreased, the final attack rate decreased among vaccinated people, but the relative “contribution of risk to vaccinated people caused by infection acquired from contact with unvaccinated people ... increased.”

When the vaccination rate was increased in the model, case numbers among the vaccinated declined “as expected, owing to indirect protective effects,” the researchers noted. But this also “further increased the relative contribution to risk in vaccinated people by those who were unvaccinated.”
 

Self-regarding risk?

The findings show that “choices made by people who forgo vaccination contribute disproportionately to risk among those who do get vaccinated,” the researchers wrote. “Although risk associated with avoiding vaccination during a virulent pandemic accrues chiefly to those who are unvaccinated, the choice of some individuals to refuse vaccination is likely to affect the health and safety of vaccinated people in a manner disproportionate to the fraction of unvaccinated people in the population.”

The fact that like-with-like mixing cannot mitigate the risk to vaccinated people “undermines the assertion that vaccine choice is best left to the individual and supports strong public actions aimed at enhancing vaccine uptake and limiting access to public spaces for unvaccinated people,” they wrote.
 

Mandates and passports

“Our model provides support for vaccine mandates and passports during epidemics, such that vaccination is required for people to take part in nonessential activities,” said Dr. Fisman. The choice to not be vaccinated against COVID-19 should not be considered “self-regarding,” he added. “Risk is self-regarding when it only impacts the person engaging in the activity. Something like smoking cigarettes (alone, without others around) creates a lot of risk over time, but if nobody is breathing your secondhand smoke, you’re only creating risk for yourself. By contrast, we regulate, in Ontario, your right to smoke in public indoor spaces such as restaurants, because once other people are around, the risk isn’t self-regarding anymore. You’re creating risk for others.”

The authors also noted that the risks created by the unvaccinated extend beyond those of infection by “creating a risk that those around them may not be able to obtain the care they need.” They recommended that considerations of equity and justice for people who do choose to be vaccinated, as well as those who choose not to be, need to be included in formulating vaccination policy.
 

Illuminating the discussion

Asked to comment on the study, Matthew Oughton, MD, assistant professor of medicine at McGill University, Montreal, said: “It is easy to dismiss a mathematical model as a series of assumptions that leads to an implausible conclusion. ... However, they can serve to illustrate and, to an extent, quantify the results of complex interactions, and this study does just that.” Dr. Oughton was not involved in the research.

During the past 2 years, the scientific press and the general press have often discussed the individual and collective effects of disease-prevention methods, including nonpharmaceutical interventions. “Models like this can help illuminate those discussions by highlighting important consequences of preventive measures,” said Dr. Oughton, who also works in the division of infectious diseases at the Jewish General Hospital, Montreal.

It’s worth noting that the authors modeled vaccine effectiveness against all infection, “rather than the generally greater and more durable effects we have seen for vaccines in prevention of severe infection,” said Dr. Oughton. He added that the authors did not include the effect of vaccination in reducing forward transmission. “Inclusion of this effect would presumably have reduced overall infectious burden in mixed populations and increased the difference between groups at lower levels of mixing between populations.”

The research was supported by a grant from the Canadian Institutes of Health Research. Dr. Fisman has served on advisory boards related to influenza and SARS-CoV-2 vaccines for Seqirus, Pfizer, AstraZeneca, and Sanofi-Pasteur Vaccines and has served as a legal expert on issues related to COVID-19 epidemiology for the Elementary Teachers Federation of Ontario and the Registered Nurses Association of Ontario. Dr. Oughton disclosed no relevant financial relationships.

A version of this article first appeared on Medscape.com.

People who are not vaccinated against a respiratory virus such as SARS-CoV-2 present a disproportionate infectious risk to those who are vaccinated, according to a mathematical modeling study.

The study, which simulated patterns of infection among vaccinated and unvaccinated populations, showed that, as the populations mixed less, attack rates decreased among vaccinated people (from 15% to 10%) and increased among unvaccinated people (from 62% to 79%). The unvaccinated increasingly became the source of infection, however.

“When the vaccinated and unvaccinated mix, indirect protection is conferred upon the unvaccinated by the buffering effect of vaccinated individuals, and by contrast, risk in the vaccinated goes up,” lead author David Fisman, MD, professor of epidemiology at the University of Toronto, told this news organization.

As the groups mix less and less, the size of the epidemic increases among the unvaccinated and decreases among the vaccinated. “But the impact of the unvaccinated on risk in the vaccinated is disproportionate to the numbers of contacts between the two groups,” said Dr. Fisman.

The study was published online in the Canadian Medical Association Journal.


 

Relative contributions to risk

The researchers used a model of a respiratory viral disease “similar to SARS-CoV-2 infection with Delta variant.” They included reproduction values to capture the dynamics of the Omicron variant, which was emerging at the time. In the study, vaccines ranged in effectiveness from 40% to 80%. The study incorporated various levels of mixing between a partially vaccinated and an unvaccinated population. The mixing ranged from random mixing to like-with-like mixing (“assortativity”). There were three possible “compartments” of people in the model: those considered susceptible to infection, those considered infected and infectious, and those considered immune because of recovery.

The model showed that, as mixing between the vaccinated and the unvaccinated populations increased, case numbers rose, “with cases in the unvaccinated subpopulation accounting for a substantial proportion of infections.” However, as mixing between the populations decreased, the final attack rate decreased among vaccinated people, but the relative “contribution of risk to vaccinated people caused by infection acquired from contact with unvaccinated people ... increased.”

When the vaccination rate was increased in the model, case numbers among the vaccinated declined “as expected, owing to indirect protective effects,” the researchers noted. But this also “further increased the relative contribution to risk in vaccinated people by those who were unvaccinated.”
 

Self-regarding risk?

The findings show that “choices made by people who forgo vaccination contribute disproportionately to risk among those who do get vaccinated,” the researchers wrote. “Although risk associated with avoiding vaccination during a virulent pandemic accrues chiefly to those who are unvaccinated, the choice of some individuals to refuse vaccination is likely to affect the health and safety of vaccinated people in a manner disproportionate to the fraction of unvaccinated people in the population.”

The fact that like-with-like mixing cannot mitigate the risk to vaccinated people “undermines the assertion that vaccine choice is best left to the individual and supports strong public actions aimed at enhancing vaccine uptake and limiting access to public spaces for unvaccinated people,” they wrote.
 

Mandates and passports

“Our model provides support for vaccine mandates and passports during epidemics, such that vaccination is required for people to take part in nonessential activities,” said Dr. Fisman. The choice to not be vaccinated against COVID-19 should not be considered “self-regarding,” he added. “Risk is self-regarding when it only impacts the person engaging in the activity. Something like smoking cigarettes (alone, without others around) creates a lot of risk over time, but if nobody is breathing your secondhand smoke, you’re only creating risk for yourself. By contrast, we regulate, in Ontario, your right to smoke in public indoor spaces such as restaurants, because once other people are around, the risk isn’t self-regarding anymore. You’re creating risk for others.”

The authors also noted that the risks created by the unvaccinated extend beyond those of infection by “creating a risk that those around them may not be able to obtain the care they need.” They recommended that considerations of equity and justice for people who do choose to be vaccinated, as well as those who choose not to be, need to be included in formulating vaccination policy.
 

Illuminating the discussion

Asked to comment on the study, Matthew Oughton, MD, assistant professor of medicine at McGill University, Montreal, said: “It is easy to dismiss a mathematical model as a series of assumptions that leads to an implausible conclusion. ... However, they can serve to illustrate and, to an extent, quantify the results of complex interactions, and this study does just that.” Dr. Oughton was not involved in the research.

During the past 2 years, the scientific press and the general press have often discussed the individual and collective effects of disease-prevention methods, including nonpharmaceutical interventions. “Models like this can help illuminate those discussions by highlighting important consequences of preventive measures,” said Dr. Oughton, who also works in the division of infectious diseases at the Jewish General Hospital, Montreal.

It’s worth noting that the authors modeled vaccine effectiveness against all infection, “rather than the generally greater and more durable effects we have seen for vaccines in prevention of severe infection,” said Dr. Oughton. He added that the authors did not include the effect of vaccination in reducing forward transmission. “Inclusion of this effect would presumably have reduced overall infectious burden in mixed populations and increased the difference between groups at lower levels of mixing between populations.”

The research was supported by a grant from the Canadian Institutes of Health Research. Dr. Fisman has served on advisory boards related to influenza and SARS-CoV-2 vaccines for Seqirus, Pfizer, AstraZeneca, and Sanofi-Pasteur Vaccines and has served as a legal expert on issues related to COVID-19 epidemiology for the Elementary Teachers Federation of Ontario and the Registered Nurses Association of Ontario. Dr. Oughton disclosed no relevant financial relationships.

A version of this article first appeared on Medscape.com.

The incidence of inflammatory bowel disease (IBD) is on the rise among racial and ethnic minority groups in the United States, and social determinants of health (SDOH) contribute to disparities in IBD care and outcome, say the authors of a new paper on the topic. 

It’s an “overdue priority to acknowledge the weight and influence of the SDOH on health disparities in IBD care,” write Adjoa Anyane-Yeboa, MD, PhD, with Massachusetts General Hospital, Boston, and co-authors.

“Only after this acknowledgement can we begin to develop alternative systems that work to rectify the deleterious effects of our current policies in a more longitudinal and effective manner,” they say. 

Their paper was published online in Clinical Gastroenterology and Hepatology.
 

Upstream factors propagate downstream outcomes

The authors found multiple examples in the literature of how upstream SDOH (for example, racism, poverty, neighborhood violence, and under-insurance) lead to midstream SDOH (for example, lack of social support, lack of access to specialized IBD care, poor housing conditions, and food insecurity) that result in poor downstream outcomes in IBD (for example, delayed diagnosis, increased disease activity, IBD flares, and suboptimal medical management). 

The IBD literature shows that Black/African American adults with IBD often have worse outcomes across the IBD care continuum than White peers, with higher hospitalization rates, longer stays, increased hospitalization costs, higher readmission rates, and more complications after IBD surgery.

Unequal access to specialized IBD care is a factor, with Black/African American patients less likely to undergo annual visits to a gastroenterologist or IBD specialist, twice as likely than White patients to visit the emergency department over a 12-month period, and less likely to receive treatment with infliximab.

As has been shown for other chronic digestive diseases and cancers, disparities in outcomes related to IBD exist across race, ethnicity, differential insurance status and coverage, and socioeconomic status, the authors note. 

Yet, they point out that, interestingly, a 2021 study of patients with Medicaid insurance from four states revealed no disparities in the use of IBD-specific medications between Black/African American and White patients, suggesting that when access to care is equal, disparities diminish.
 

Target multiple stakeholders to achieve IBD health equity 

Achieving health equity in IBD will require strategies targeting medical trainees, providers, practices, and health systems, as well as community and industry leaders and policymakers, Dr. Anyane-Yeboa and colleagues say. 

At the medical trainee level, racism and bias should be addressed early in medical student, resident, and fellow training and education. Curricula should move away from race-based training, where race is considered an independent risk factor for disease and often used to guide differential diagnoses and treatment, they suggest. 

At the provider level, they say self-reflection around one’s own beliefs, biases, perceptions, and interactions with diverse and vulnerable patient groups is “paramount.” Individual self-reflection should be coupled with mandatory and effective implicit bias and anti-racism training. 

At the practice or hospital system level, screening for SDOH at the point of care, addressing barriers to needed treatment, and connecting patients to appropriate resources are all important, they write. 

The researchers also call for policy-level changes to increase funding for health equity research, which is historically undervalued and underfunded.

“Focusing on SDOH as the root cause of health inequity in IBD is essential to improve outcomes for marginalized patients,” they write.

Given that research describing specific interventions to address SDOH in IBD is currently nonexistent, “our paper serves as a call to action for more work to be done in this area,” they say. 

“As medical providers and health care organizations, we all have a responsibility to address the SDOH when caring for our patients in order to provide each patient with IBD the opportunity to achieve the best health possible,” they conclude. 

This research had no specific funding. The authors have disclosed no relevant financial relationships. 

A version of this article first appeared on Medscape.com.

The incidence of inflammatory bowel disease (IBD) is on the rise among racial and ethnic minority groups in the United States, and social determinants of health (SDOH) contribute to disparities in IBD care and outcome, say the authors of a new paper on the topic. 

It’s an “overdue priority to acknowledge the weight and influence of the SDOH on health disparities in IBD care,” write Adjoa Anyane-Yeboa, MD, PhD, with Massachusetts General Hospital, Boston, and co-authors.

“Only after this acknowledgement can we begin to develop alternative systems that work to rectify the deleterious effects of our current policies in a more longitudinal and effective manner,” they say. 

Their paper was published online in Clinical Gastroenterology and Hepatology.
 

Upstream factors propagate downstream outcomes

The authors found multiple examples in the literature of how upstream SDOH (for example, racism, poverty, neighborhood violence, and under-insurance) lead to midstream SDOH (for example, lack of social support, lack of access to specialized IBD care, poor housing conditions, and food insecurity) that result in poor downstream outcomes in IBD (for example, delayed diagnosis, increased disease activity, IBD flares, and suboptimal medical management). 

The IBD literature shows that Black/African American adults with IBD often have worse outcomes across the IBD care continuum than White peers, with higher hospitalization rates, longer stays, increased hospitalization costs, higher readmission rates, and more complications after IBD surgery.

Unequal access to specialized IBD care is a factor, with Black/African American patients less likely to undergo annual visits to a gastroenterologist or IBD specialist, twice as likely than White patients to visit the emergency department over a 12-month period, and less likely to receive treatment with infliximab.

As has been shown for other chronic digestive diseases and cancers, disparities in outcomes related to IBD exist across race, ethnicity, differential insurance status and coverage, and socioeconomic status, the authors note. 

Yet, they point out that, interestingly, a 2021 study of patients with Medicaid insurance from four states revealed no disparities in the use of IBD-specific medications between Black/African American and White patients, suggesting that when access to care is equal, disparities diminish.
 

Target multiple stakeholders to achieve IBD health equity 

Achieving health equity in IBD will require strategies targeting medical trainees, providers, practices, and health systems, as well as community and industry leaders and policymakers, Dr. Anyane-Yeboa and colleagues say. 

At the medical trainee level, racism and bias should be addressed early in medical student, resident, and fellow training and education. Curricula should move away from race-based training, where race is considered an independent risk factor for disease and often used to guide differential diagnoses and treatment, they suggest. 

At the provider level, they say self-reflection around one’s own beliefs, biases, perceptions, and interactions with diverse and vulnerable patient groups is “paramount.” Individual self-reflection should be coupled with mandatory and effective implicit bias and anti-racism training. 

At the practice or hospital system level, screening for SDOH at the point of care, addressing barriers to needed treatment, and connecting patients to appropriate resources are all important, they write. 

The researchers also call for policy-level changes to increase funding for health equity research, which is historically undervalued and underfunded.

“Focusing on SDOH as the root cause of health inequity in IBD is essential to improve outcomes for marginalized patients,” they write.

Given that research describing specific interventions to address SDOH in IBD is currently nonexistent, “our paper serves as a call to action for more work to be done in this area,” they say. 

“As medical providers and health care organizations, we all have a responsibility to address the SDOH when caring for our patients in order to provide each patient with IBD the opportunity to achieve the best health possible,” they conclude. 

This research had no specific funding. The authors have disclosed no relevant financial relationships. 

A version of this article first appeared on Medscape.com.

The incidence of inflammatory bowel disease (IBD) is on the rise among racial and ethnic minority groups in the United States, and social determinants of health (SDOH) contribute to disparities in IBD care and outcome, say the authors of a new paper on the topic. 

It’s an “overdue priority to acknowledge the weight and influence of the SDOH on health disparities in IBD care,” write Adjoa Anyane-Yeboa, MD, PhD, with Massachusetts General Hospital, Boston, and co-authors.

“Only after this acknowledgement can we begin to develop alternative systems that work to rectify the deleterious effects of our current policies in a more longitudinal and effective manner,” they say. 

Their paper was published online in Clinical Gastroenterology and Hepatology.
 

Upstream factors propagate downstream outcomes

The authors found multiple examples in the literature of how upstream SDOH (for example, racism, poverty, neighborhood violence, and under-insurance) lead to midstream SDOH (for example, lack of social support, lack of access to specialized IBD care, poor housing conditions, and food insecurity) that result in poor downstream outcomes in IBD (for example, delayed diagnosis, increased disease activity, IBD flares, and suboptimal medical management). 

The IBD literature shows that Black/African American adults with IBD often have worse outcomes across the IBD care continuum than White peers, with higher hospitalization rates, longer stays, increased hospitalization costs, higher readmission rates, and more complications after IBD surgery.

Unequal access to specialized IBD care is a factor, with Black/African American patients less likely to undergo annual visits to a gastroenterologist or IBD specialist, twice as likely than White patients to visit the emergency department over a 12-month period, and less likely to receive treatment with infliximab.

As has been shown for other chronic digestive diseases and cancers, disparities in outcomes related to IBD exist across race, ethnicity, differential insurance status and coverage, and socioeconomic status, the authors note. 

Yet, they point out that, interestingly, a 2021 study of patients with Medicaid insurance from four states revealed no disparities in the use of IBD-specific medications between Black/African American and White patients, suggesting that when access to care is equal, disparities diminish.
 

Target multiple stakeholders to achieve IBD health equity 

Achieving health equity in IBD will require strategies targeting medical trainees, providers, practices, and health systems, as well as community and industry leaders and policymakers, Dr. Anyane-Yeboa and colleagues say. 

At the medical trainee level, racism and bias should be addressed early in medical student, resident, and fellow training and education. Curricula should move away from race-based training, where race is considered an independent risk factor for disease and often used to guide differential diagnoses and treatment, they suggest. 

At the provider level, they say self-reflection around one’s own beliefs, biases, perceptions, and interactions with diverse and vulnerable patient groups is “paramount.” Individual self-reflection should be coupled with mandatory and effective implicit bias and anti-racism training. 

At the practice or hospital system level, screening for SDOH at the point of care, addressing barriers to needed treatment, and connecting patients to appropriate resources are all important, they write. 

The researchers also call for policy-level changes to increase funding for health equity research, which is historically undervalued and underfunded.

“Focusing on SDOH as the root cause of health inequity in IBD is essential to improve outcomes for marginalized patients,” they write.

Given that research describing specific interventions to address SDOH in IBD is currently nonexistent, “our paper serves as a call to action for more work to be done in this area,” they say. 

“As medical providers and health care organizations, we all have a responsibility to address the SDOH when caring for our patients in order to provide each patient with IBD the opportunity to achieve the best health possible,” they conclude. 

This research had no specific funding. The authors have disclosed no relevant financial relationships. 

A version of this article first appeared on Medscape.com.

Coronavirus-related hospital admissions and deaths in the United States are projected to increase over the next four weeks, according to a national forecast used by the Centers for Disease Control and Prevention.

The national model also predicts that about 5,000 deaths will occur over the next two weeks, with Ohio, New Jersey, and New York projected to see the largest totals of daily deaths in upcoming weeks.

The numbers follow several weeks of steady increases in infections across the country. More than 67,000 new cases are being reported daily, according to the data tracker from The New York Times, marking a 59% increase in the past two weeks.

In the Northeast, infection rates have risen by nearly 65%. In the New York and New Jersey region, infection rates are up about 55% in the past two weeks.

Hospitalizations have already begun to climb as well, with about 19,000 COVID-19 patients hospitalized nationwide and 1,725 in intensive care, according to the latest data from the Department of Health and Human Services. In the last week, hospital admissions have jumped by 20%, and emergency department visits are up by 18%.

The CDC forecast shows that 42 states and territories will see increases in hospital admissions during the next two weeks. Florida, Minnesota, New York, and Wisconsin will see some of the largest increases.

On average, more than 2,200 COVID-19 patients are entering the hospital each day, which has increased about 20% in the last week, according to ABC News. This also marks the highest number of COVID-19 patients needing hospital care since mid-March.

Public health officials have cited several factors for the increase in cases, such as states lifting mask mandates and other safety restrictions, ABC News reported. Highly contagious Omicron subvariants, such as BA.2 and BA.2.12.1, continue to spread in the United States and escape immunity from previous infections.

The BA.2 subvariant accounts for 62% of new national cases, according to the latest CDC data. The BA.2.12.1 subvariant makes up about 36% of new cases across the United States but 62% in the New York area.

A version of this article first appeared on WebMD.com.

Coronavirus-related hospital admissions and deaths in the United States are projected to increase over the next four weeks, according to a national forecast used by the Centers for Disease Control and Prevention.

The national model also predicts that about 5,000 deaths will occur over the next two weeks, with Ohio, New Jersey, and New York projected to see the largest totals of daily deaths in upcoming weeks.

The numbers follow several weeks of steady increases in infections across the country. More than 67,000 new cases are being reported daily, according to the data tracker from The New York Times, marking a 59% increase in the past two weeks.

In the Northeast, infection rates have risen by nearly 65%. In the New York and New Jersey region, infection rates are up about 55% in the past two weeks.

Hospitalizations have already begun to climb as well, with about 19,000 COVID-19 patients hospitalized nationwide and 1,725 in intensive care, according to the latest data from the Department of Health and Human Services. In the last week, hospital admissions have jumped by 20%, and emergency department visits are up by 18%.

The CDC forecast shows that 42 states and territories will see increases in hospital admissions during the next two weeks. Florida, Minnesota, New York, and Wisconsin will see some of the largest increases.

On average, more than 2,200 COVID-19 patients are entering the hospital each day, which has increased about 20% in the last week, according to ABC News. This also marks the highest number of COVID-19 patients needing hospital care since mid-March.

Public health officials have cited several factors for the increase in cases, such as states lifting mask mandates and other safety restrictions, ABC News reported. Highly contagious Omicron subvariants, such as BA.2 and BA.2.12.1, continue to spread in the United States and escape immunity from previous infections.

The BA.2 subvariant accounts for 62% of new national cases, according to the latest CDC data. The BA.2.12.1 subvariant makes up about 36% of new cases across the United States but 62% in the New York area.

A version of this article first appeared on WebMD.com.

Coronavirus-related hospital admissions and deaths in the United States are projected to increase over the next four weeks, according to a national forecast used by the Centers for Disease Control and Prevention.

The national model also predicts that about 5,000 deaths will occur over the next two weeks, with Ohio, New Jersey, and New York projected to see the largest totals of daily deaths in upcoming weeks.

The numbers follow several weeks of steady increases in infections across the country. More than 67,000 new cases are being reported daily, according to the data tracker from The New York Times, marking a 59% increase in the past two weeks.

In the Northeast, infection rates have risen by nearly 65%. In the New York and New Jersey region, infection rates are up about 55% in the past two weeks.

Hospitalizations have already begun to climb as well, with about 19,000 COVID-19 patients hospitalized nationwide and 1,725 in intensive care, according to the latest data from the Department of Health and Human Services. In the last week, hospital admissions have jumped by 20%, and emergency department visits are up by 18%.

The CDC forecast shows that 42 states and territories will see increases in hospital admissions during the next two weeks. Florida, Minnesota, New York, and Wisconsin will see some of the largest increases.

On average, more than 2,200 COVID-19 patients are entering the hospital each day, which has increased about 20% in the last week, according to ABC News. This also marks the highest number of COVID-19 patients needing hospital care since mid-March.

Public health officials have cited several factors for the increase in cases, such as states lifting mask mandates and other safety restrictions, ABC News reported. Highly contagious Omicron subvariants, such as BA.2 and BA.2.12.1, continue to spread in the United States and escape immunity from previous infections.

The BA.2 subvariant accounts for 62% of new national cases, according to the latest CDC data. The BA.2.12.1 subvariant makes up about 36% of new cases across the United States but 62% in the New York area.

A version of this article first appeared on WebMD.com.

Obesity, in combination with other risk factors, is associated with increased morbidity and mortality in acute pancreatitis (AP); however, body mass index (BMI) alone is not a successful predictor of disease severity, new research shows.

“As there was no agreement or consistency between BMI and AP severity, it can be concluded that AP severity cannot be predicted successfully by examining BMI only,” reported the authors in research published recently in Pancreatology.

iStock/ThinkStock

The course of acute pancreatitis is typically mild in the majority (80%-85%) of cases; however, in severe cases, permanent organ failure can occur, with much worse outcomes and mortality rates of up to 35%.

Research has previously shown not only a link between obesity and acute pancreatitis but also an increased risk for complications and in-hospital mortality in obese patients with severe cases of acute pancreatitis – though a wide range of factors and comorbidities may complicate the association.

To more closely evaluate the course and outcomes of acute pancreatitis based on BMI classification, study authors led by Ali Tuzun Ince, MD, of the department of internal medicine, Gastroenterology Clinic of Bezmialem Vakif University, Istanbul, analyzed retrospective data from 2010 to 2020 on 1,334 adult patients (720 female, 614 male) who were diagnosed with acute pancreatitis per the Revised Atlanta Classification (RAC) criteria.

The patients were stratified based on their BMI as normal weight, overweight, or obese and whether they had mild, moderate, or severe (with permanent organ failure) acute pancreatitis.

In terms of acute pancreatitis severity, based on RAC criteria, 57.1% of patients had mild disease, 20.4% had moderate disease, and 22.5% had severe disease.

The overall mortality rate was 9.9% (n = 132); half of these patients were obese, and 87% had severe acute pancreatitis.

The overall rate of complications was 42.9%, including 20.8% in the normal weight group, 40.6% in the overweight group, and 38.6% in the obese group.

Patients in the overweight and obese groups also had higher mortality rates (3.7% and 4.9%, respectively), interventional procedures (36% and 39%, respectively), and length of hospital stay (11.6% and 9.8%, respectively), compared with the normal-weight group.

Other factors that were significantly associated with an increased mortality risk, in addition to obesity (P = .046), included old age (P = .000), male sex (P = .05), alcohol use (P = .014), low hematocrit (P = .044), high C-reactive protein (P = .024), moderate to severe and severe acute pancreatitis (P = .02 and P < .001, respectively), and any complications (P < .001).

Risk factors associated with increased admission to the ICU differed from those for mortality, and included female gender (P = .024), smoking (P = .021), hypertriglyceridemia (P = .047), idiopathic etiology (P = .023), and moderate to severe and severe acute pancreatitis (P < .001).

Of note, there were no significant associations between BMI and either the RAC score or Balthazar CT severity index (Balthazar CTSI) groups.

Specifically, among patients considered to have severe acute pancreatitis per Balthazar CTSI, 6.3% were of normal weight, 5% were overweight, and 7.1% were obese.

“In addition, since agreement and consistency between BMI and Balthazar score cannot be determined, the Balthazar score cannot be estimated from BMI,” the authors reported.

While the prediction of prognosis in acute pancreatitis is gaining interest, the findings underscore the role of combined factors, they added.

“Although many scoring systems are currently in use attempt to estimate the severity [in acute pancreatitis], none is 100% accurate yet,” the authors noted. “Each risk factor exacerbates the course of disease. Therefore, it would be better to consider the combined effects of risk factors.”

That being said, the findings show “mortality is increased significantly by the combined presence of risk factors such as male sex, OB [obesity], alcohol, MSAP [moderate to severe acute pancreatitis] and SAP [severe acute pancreatitis], all kinds of complications, old age, low Hct, and high CRP,” they wrote.
 

Obesity’s complex interactions

Commenting on the study, Vijay P. Singh, MD, a professor of medicine in the division of gastroenterology and hepatology at the Mayo Clinic in Scottsdale, Ariz., agreed that the complexities risk factors, particularly with obesity, can be tricky to detangle.

“Broadly, the study confirms several previous reports from different parts of the world that obesity was associated with increased mortality in acute pancreatitis,” he said in an interview.

“However, obesity had two complex interactions, the first that obesity is also associated with increased diabetes, and hypertriglyceridemia, which may themselves be risk factors for severity,” he explained.

“The second one is that intermediary severity markers [e.g., Balthazar score on imaging] did not correlate with the BMI categories.”

Dr. Singh noted that is “likely because therapies like IV fluids that may get more intense in predicted severe disease alter the natural course of pancreatitis.”

The findings are a reminder that “BMI is only a number that attempts to quantify fat,” Dr. Singh said, noting that BMI doesn’t address either the location of fat, such as being in close proximity to the pancreas, or fat composition, such as the proportion of unsaturated fat.

“When the unsaturated fat proportion is higher, the pancreatitis is worse, even at smaller total fat amounts [for example, at a lower BMI],” he said. “Taking these aspects into account may help in risk assessment.”

The authors and Dr. Singh had no disclosures to report.

Obesity, in combination with other risk factors, is associated with increased morbidity and mortality in acute pancreatitis (AP); however, body mass index (BMI) alone is not a successful predictor of disease severity, new research shows.

“As there was no agreement or consistency between BMI and AP severity, it can be concluded that AP severity cannot be predicted successfully by examining BMI only,” reported the authors in research published recently in Pancreatology.

iStock/ThinkStock

The course of acute pancreatitis is typically mild in the majority (80%-85%) of cases; however, in severe cases, permanent organ failure can occur, with much worse outcomes and mortality rates of up to 35%.

Research has previously shown not only a link between obesity and acute pancreatitis but also an increased risk for complications and in-hospital mortality in obese patients with severe cases of acute pancreatitis – though a wide range of factors and comorbidities may complicate the association.

To more closely evaluate the course and outcomes of acute pancreatitis based on BMI classification, study authors led by Ali Tuzun Ince, MD, of the department of internal medicine, Gastroenterology Clinic of Bezmialem Vakif University, Istanbul, analyzed retrospective data from 2010 to 2020 on 1,334 adult patients (720 female, 614 male) who were diagnosed with acute pancreatitis per the Revised Atlanta Classification (RAC) criteria.

The patients were stratified based on their BMI as normal weight, overweight, or obese and whether they had mild, moderate, or severe (with permanent organ failure) acute pancreatitis.

In terms of acute pancreatitis severity, based on RAC criteria, 57.1% of patients had mild disease, 20.4% had moderate disease, and 22.5% had severe disease.

The overall mortality rate was 9.9% (n = 132); half of these patients were obese, and 87% had severe acute pancreatitis.

The overall rate of complications was 42.9%, including 20.8% in the normal weight group, 40.6% in the overweight group, and 38.6% in the obese group.

Patients in the overweight and obese groups also had higher mortality rates (3.7% and 4.9%, respectively), interventional procedures (36% and 39%, respectively), and length of hospital stay (11.6% and 9.8%, respectively), compared with the normal-weight group.

Other factors that were significantly associated with an increased mortality risk, in addition to obesity (P = .046), included old age (P = .000), male sex (P = .05), alcohol use (P = .014), low hematocrit (P = .044), high C-reactive protein (P = .024), moderate to severe and severe acute pancreatitis (P = .02 and P < .001, respectively), and any complications (P < .001).

Risk factors associated with increased admission to the ICU differed from those for mortality, and included female gender (P = .024), smoking (P = .021), hypertriglyceridemia (P = .047), idiopathic etiology (P = .023), and moderate to severe and severe acute pancreatitis (P < .001).

Of note, there were no significant associations between BMI and either the RAC score or Balthazar CT severity index (Balthazar CTSI) groups.

Specifically, among patients considered to have severe acute pancreatitis per Balthazar CTSI, 6.3% were of normal weight, 5% were overweight, and 7.1% were obese.

“In addition, since agreement and consistency between BMI and Balthazar score cannot be determined, the Balthazar score cannot be estimated from BMI,” the authors reported.

While the prediction of prognosis in acute pancreatitis is gaining interest, the findings underscore the role of combined factors, they added.

“Although many scoring systems are currently in use attempt to estimate the severity [in acute pancreatitis], none is 100% accurate yet,” the authors noted. “Each risk factor exacerbates the course of disease. Therefore, it would be better to consider the combined effects of risk factors.”

That being said, the findings show “mortality is increased significantly by the combined presence of risk factors such as male sex, OB [obesity], alcohol, MSAP [moderate to severe acute pancreatitis] and SAP [severe acute pancreatitis], all kinds of complications, old age, low Hct, and high CRP,” they wrote.
 

Obesity’s complex interactions

Commenting on the study, Vijay P. Singh, MD, a professor of medicine in the division of gastroenterology and hepatology at the Mayo Clinic in Scottsdale, Ariz., agreed that the complexities risk factors, particularly with obesity, can be tricky to detangle.

“Broadly, the study confirms several previous reports from different parts of the world that obesity was associated with increased mortality in acute pancreatitis,” he said in an interview.

“However, obesity had two complex interactions, the first that obesity is also associated with increased diabetes, and hypertriglyceridemia, which may themselves be risk factors for severity,” he explained.

“The second one is that intermediary severity markers [e.g., Balthazar score on imaging] did not correlate with the BMI categories.”

Dr. Singh noted that is “likely because therapies like IV fluids that may get more intense in predicted severe disease alter the natural course of pancreatitis.”

The findings are a reminder that “BMI is only a number that attempts to quantify fat,” Dr. Singh said, noting that BMI doesn’t address either the location of fat, such as being in close proximity to the pancreas, or fat composition, such as the proportion of unsaturated fat.

“When the unsaturated fat proportion is higher, the pancreatitis is worse, even at smaller total fat amounts [for example, at a lower BMI],” he said. “Taking these aspects into account may help in risk assessment.”

The authors and Dr. Singh had no disclosures to report.

Obesity, in combination with other risk factors, is associated with increased morbidity and mortality in acute pancreatitis (AP); however, body mass index (BMI) alone is not a successful predictor of disease severity, new research shows.

“As there was no agreement or consistency between BMI and AP severity, it can be concluded that AP severity cannot be predicted successfully by examining BMI only,” reported the authors in research published recently in Pancreatology.

iStock/ThinkStock

The course of acute pancreatitis is typically mild in the majority (80%-85%) of cases; however, in severe cases, permanent organ failure can occur, with much worse outcomes and mortality rates of up to 35%.

Research has previously shown not only a link between obesity and acute pancreatitis but also an increased risk for complications and in-hospital mortality in obese patients with severe cases of acute pancreatitis – though a wide range of factors and comorbidities may complicate the association.

To more closely evaluate the course and outcomes of acute pancreatitis based on BMI classification, study authors led by Ali Tuzun Ince, MD, of the department of internal medicine, Gastroenterology Clinic of Bezmialem Vakif University, Istanbul, analyzed retrospective data from 2010 to 2020 on 1,334 adult patients (720 female, 614 male) who were diagnosed with acute pancreatitis per the Revised Atlanta Classification (RAC) criteria.

The patients were stratified based on their BMI as normal weight, overweight, or obese and whether they had mild, moderate, or severe (with permanent organ failure) acute pancreatitis.

In terms of acute pancreatitis severity, based on RAC criteria, 57.1% of patients had mild disease, 20.4% had moderate disease, and 22.5% had severe disease.

The overall mortality rate was 9.9% (n = 132); half of these patients were obese, and 87% had severe acute pancreatitis.

The overall rate of complications was 42.9%, including 20.8% in the normal weight group, 40.6% in the overweight group, and 38.6% in the obese group.

Patients in the overweight and obese groups also had higher mortality rates (3.7% and 4.9%, respectively), interventional procedures (36% and 39%, respectively), and length of hospital stay (11.6% and 9.8%, respectively), compared with the normal-weight group.

Other factors that were significantly associated with an increased mortality risk, in addition to obesity (P = .046), included old age (P = .000), male sex (P = .05), alcohol use (P = .014), low hematocrit (P = .044), high C-reactive protein (P = .024), moderate to severe and severe acute pancreatitis (P = .02 and P < .001, respectively), and any complications (P < .001).

Risk factors associated with increased admission to the ICU differed from those for mortality, and included female gender (P = .024), smoking (P = .021), hypertriglyceridemia (P = .047), idiopathic etiology (P = .023), and moderate to severe and severe acute pancreatitis (P < .001).

Of note, there were no significant associations between BMI and either the RAC score or Balthazar CT severity index (Balthazar CTSI) groups.

Specifically, among patients considered to have severe acute pancreatitis per Balthazar CTSI, 6.3% were of normal weight, 5% were overweight, and 7.1% were obese.

“In addition, since agreement and consistency between BMI and Balthazar score cannot be determined, the Balthazar score cannot be estimated from BMI,” the authors reported.

While the prediction of prognosis in acute pancreatitis is gaining interest, the findings underscore the role of combined factors, they added.

“Although many scoring systems are currently in use attempt to estimate the severity [in acute pancreatitis], none is 100% accurate yet,” the authors noted. “Each risk factor exacerbates the course of disease. Therefore, it would be better to consider the combined effects of risk factors.”

That being said, the findings show “mortality is increased significantly by the combined presence of risk factors such as male sex, OB [obesity], alcohol, MSAP [moderate to severe acute pancreatitis] and SAP [severe acute pancreatitis], all kinds of complications, old age, low Hct, and high CRP,” they wrote.
 

Obesity’s complex interactions

Commenting on the study, Vijay P. Singh, MD, a professor of medicine in the division of gastroenterology and hepatology at the Mayo Clinic in Scottsdale, Ariz., agreed that the complexities risk factors, particularly with obesity, can be tricky to detangle.

“Broadly, the study confirms several previous reports from different parts of the world that obesity was associated with increased mortality in acute pancreatitis,” he said in an interview.

“However, obesity had two complex interactions, the first that obesity is also associated with increased diabetes, and hypertriglyceridemia, which may themselves be risk factors for severity,” he explained.

“The second one is that intermediary severity markers [e.g., Balthazar score on imaging] did not correlate with the BMI categories.”

Dr. Singh noted that is “likely because therapies like IV fluids that may get more intense in predicted severe disease alter the natural course of pancreatitis.”

The findings are a reminder that “BMI is only a number that attempts to quantify fat,” Dr. Singh said, noting that BMI doesn’t address either the location of fat, such as being in close proximity to the pancreas, or fat composition, such as the proportion of unsaturated fat.

“When the unsaturated fat proportion is higher, the pancreatitis is worse, even at smaller total fat amounts [for example, at a lower BMI],” he said. “Taking these aspects into account may help in risk assessment.”

The authors and Dr. Singh had no disclosures to report.

An investigational, novel oral antibiotic with greater selectivity than vancomycin, metronidazole, and even fidaxomicin may offer improved protection of healthy gut bacteria during the treatment of Clostridium difficile infection (CDI), according to ongoing research.

“CDI treatment has historically been dominated by metronidazole and vancomycin,” said Katherine Johnson, DO, from the Western Infectious Disease Consultants, P.C., Denver. However, these broad-spectrum drugs negatively affect healthy bacteria in the gut and increase the risk of CDI recurrence.

This is also a problem for drugs in the CDI antibiotic pipeline: Many candidate drugs have failed because of their broad-spectrum activity, she added during a session at the Peggy Lillis Foundation 2022 National C. diff. Advocacy Summit.

“An ideal CDI therapy would be a very narrow-spectrum antibiotic that has a minimal effect on normal gut bacteria,” she said.

Dr. Johnson is currently working on a phase 2 clinical trial that is evaluating the novel antibiotic, dubbed CRS3123, for the treatment of primary CDI and first-recurrence CDI. The investigational agent targets and inhibits a form of the methionyl tRNA synthetase enzyme, which is strictly required for protein biosynthesis in C. diff. and is therefore an ideal target for treatment of primary and recurrent CDI.

In her session, Dr. Johnson reported that CRS3123 inhibits the damaging toxins produced by C. diff., potentially resulting in more rapid symptom resolution. Additionally, owing to its novel mode of action, no strains are currently resistant to CRS3123.

She presented findings from an animal study that showed that CRS3123 was superior to vancomycin in terms of prolonging survival. She also presented findings from phase 1 clinical trials that showed that most adverse events (AEs) associated with CRS3123 were mild. No serious AEs were reported.
 

A ‘huge infectious burden’

If successful in further research, CRS3123 could offer significant value to patients with C. diff., especially those with recurrent infection, given the sometimes extreme clinical, quality-of-life, and economic burdens associated with CDI.

“CDI is a huge infectious burden to the U.S. health care system and globally has been listed by the Centers for Disease Control and Prevention as an urgent threat,” Byron Vaughn, MD, from the University of Minnesota, told this news organization.

“Despite a number of antibiotic stewardship and infection control and prevention efforts, we haven’t seen much of a change in the incidence of CDI,” he said. He said that the risk of recurrence can be as high as 30%.

While oral vancomycin is effective for treating C. diff., Dr. Vaughn noted that the antibiotic lacks selectivity and destroys healthy gut bacteria, resulting in substantial dysbiosis. “Dysbiosis is really the key to getting recurrent C. diff.,” he explained, “because if you have healthy gut bacteria, you will inherently resist CDI.”

Dr. Vaughn stated that his center is in the startup phase for being a site for a clinical trial of CRS3123. The hope is that CRS3123, because its spectrum is narrower than that of fidaxomicin and vancomycin, doesn’t induce intestinal dysbiosis. “It really just treats the C. diff. and leaves every other bug alone so that your gut bacteria can recover while the C. diff. is being treated,” he said. “And then when you stop CRS3123, you have healthy gut bacteria already present to prevent recurrence.”

If this is confirmed in large-scale trials, there could be a “dramatic decrease” in the rates of recurrent C. diff., said Dr. Vaughn.

Aside from the potential clinical impact, the economic implications of a novel selective antibiotic that preserves healthy gut bacteria could be significant, he added. “Depending on exactly what population you’re looking at, probably about a third of the cost of C. diff. is actually attributable to recurrence. That’s a huge economic burden that could be improved.”

Dr. Johnson is an employee of Crestone, which is developing CRS3123. Dr. Vaughn reports no relevant financial relationships.

A version of this article first appeared on Medscape.com.

An investigational, novel oral antibiotic with greater selectivity than vancomycin, metronidazole, and even fidaxomicin may offer improved protection of healthy gut bacteria during the treatment of Clostridium difficile infection (CDI), according to ongoing research.

“CDI treatment has historically been dominated by metronidazole and vancomycin,” said Katherine Johnson, DO, from the Western Infectious Disease Consultants, P.C., Denver. However, these broad-spectrum drugs negatively affect healthy bacteria in the gut and increase the risk of CDI recurrence.

This is also a problem for drugs in the CDI antibiotic pipeline: Many candidate drugs have failed because of their broad-spectrum activity, she added during a session at the Peggy Lillis Foundation 2022 National C. diff. Advocacy Summit.

“An ideal CDI therapy would be a very narrow-spectrum antibiotic that has a minimal effect on normal gut bacteria,” she said.

Dr. Johnson is currently working on a phase 2 clinical trial that is evaluating the novel antibiotic, dubbed CRS3123, for the treatment of primary CDI and first-recurrence CDI. The investigational agent targets and inhibits a form of the methionyl tRNA synthetase enzyme, which is strictly required for protein biosynthesis in C. diff. and is therefore an ideal target for treatment of primary and recurrent CDI.

In her session, Dr. Johnson reported that CRS3123 inhibits the damaging toxins produced by C. diff., potentially resulting in more rapid symptom resolution. Additionally, owing to its novel mode of action, no strains are currently resistant to CRS3123.

She presented findings from an animal study that showed that CRS3123 was superior to vancomycin in terms of prolonging survival. She also presented findings from phase 1 clinical trials that showed that most adverse events (AEs) associated with CRS3123 were mild. No serious AEs were reported.
 

A ‘huge infectious burden’

If successful in further research, CRS3123 could offer significant value to patients with C. diff., especially those with recurrent infection, given the sometimes extreme clinical, quality-of-life, and economic burdens associated with CDI.

“CDI is a huge infectious burden to the U.S. health care system and globally has been listed by the Centers for Disease Control and Prevention as an urgent threat,” Byron Vaughn, MD, from the University of Minnesota, told this news organization.

“Despite a number of antibiotic stewardship and infection control and prevention efforts, we haven’t seen much of a change in the incidence of CDI,” he said. He said that the risk of recurrence can be as high as 30%.

While oral vancomycin is effective for treating C. diff., Dr. Vaughn noted that the antibiotic lacks selectivity and destroys healthy gut bacteria, resulting in substantial dysbiosis. “Dysbiosis is really the key to getting recurrent C. diff.,” he explained, “because if you have healthy gut bacteria, you will inherently resist CDI.”

Dr. Vaughn stated that his center is in the startup phase for being a site for a clinical trial of CRS3123. The hope is that CRS3123, because its spectrum is narrower than that of fidaxomicin and vancomycin, doesn’t induce intestinal dysbiosis. “It really just treats the C. diff. and leaves every other bug alone so that your gut bacteria can recover while the C. diff. is being treated,” he said. “And then when you stop CRS3123, you have healthy gut bacteria already present to prevent recurrence.”

If this is confirmed in large-scale trials, there could be a “dramatic decrease” in the rates of recurrent C. diff., said Dr. Vaughn.

Aside from the potential clinical impact, the economic implications of a novel selective antibiotic that preserves healthy gut bacteria could be significant, he added. “Depending on exactly what population you’re looking at, probably about a third of the cost of C. diff. is actually attributable to recurrence. That’s a huge economic burden that could be improved.”

Dr. Johnson is an employee of Crestone, which is developing CRS3123. Dr. Vaughn reports no relevant financial relationships.

A version of this article first appeared on Medscape.com.

An investigational, novel oral antibiotic with greater selectivity than vancomycin, metronidazole, and even fidaxomicin may offer improved protection of healthy gut bacteria during the treatment of Clostridium difficile infection (CDI), according to ongoing research.

“CDI treatment has historically been dominated by metronidazole and vancomycin,” said Katherine Johnson, DO, from the Western Infectious Disease Consultants, P.C., Denver. However, these broad-spectrum drugs negatively affect healthy bacteria in the gut and increase the risk of CDI recurrence.

This is also a problem for drugs in the CDI antibiotic pipeline: Many candidate drugs have failed because of their broad-spectrum activity, she added during a session at the Peggy Lillis Foundation 2022 National C. diff. Advocacy Summit.

“An ideal CDI therapy would be a very narrow-spectrum antibiotic that has a minimal effect on normal gut bacteria,” she said.

Dr. Johnson is currently working on a phase 2 clinical trial that is evaluating the novel antibiotic, dubbed CRS3123, for the treatment of primary CDI and first-recurrence CDI. The investigational agent targets and inhibits a form of the methionyl tRNA synthetase enzyme, which is strictly required for protein biosynthesis in C. diff. and is therefore an ideal target for treatment of primary and recurrent CDI.

In her session, Dr. Johnson reported that CRS3123 inhibits the damaging toxins produced by C. diff., potentially resulting in more rapid symptom resolution. Additionally, owing to its novel mode of action, no strains are currently resistant to CRS3123.

She presented findings from an animal study that showed that CRS3123 was superior to vancomycin in terms of prolonging survival. She also presented findings from phase 1 clinical trials that showed that most adverse events (AEs) associated with CRS3123 were mild. No serious AEs were reported.
 

A ‘huge infectious burden’

If successful in further research, CRS3123 could offer significant value to patients with C. diff., especially those with recurrent infection, given the sometimes extreme clinical, quality-of-life, and economic burdens associated with CDI.

“CDI is a huge infectious burden to the U.S. health care system and globally has been listed by the Centers for Disease Control and Prevention as an urgent threat,” Byron Vaughn, MD, from the University of Minnesota, told this news organization.

“Despite a number of antibiotic stewardship and infection control and prevention efforts, we haven’t seen much of a change in the incidence of CDI,” he said. He said that the risk of recurrence can be as high as 30%.

While oral vancomycin is effective for treating C. diff., Dr. Vaughn noted that the antibiotic lacks selectivity and destroys healthy gut bacteria, resulting in substantial dysbiosis. “Dysbiosis is really the key to getting recurrent C. diff.,” he explained, “because if you have healthy gut bacteria, you will inherently resist CDI.”

Dr. Vaughn stated that his center is in the startup phase for being a site for a clinical trial of CRS3123. The hope is that CRS3123, because its spectrum is narrower than that of fidaxomicin and vancomycin, doesn’t induce intestinal dysbiosis. “It really just treats the C. diff. and leaves every other bug alone so that your gut bacteria can recover while the C. diff. is being treated,” he said. “And then when you stop CRS3123, you have healthy gut bacteria already present to prevent recurrence.”

If this is confirmed in large-scale trials, there could be a “dramatic decrease” in the rates of recurrent C. diff., said Dr. Vaughn.

Aside from the potential clinical impact, the economic implications of a novel selective antibiotic that preserves healthy gut bacteria could be significant, he added. “Depending on exactly what population you’re looking at, probably about a third of the cost of C. diff. is actually attributable to recurrence. That’s a huge economic burden that could be improved.”

Dr. Johnson is an employee of Crestone, which is developing CRS3123. Dr. Vaughn reports no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Clostridioides difficile infection is often confirmed through toxin testing, yet toxin tests alone may not be sufficient for diagnosing and guiding treatment decisions for patients with CDI.

“The presence of a toxigenic strain does not always equal disease,” said David Lyerly, PhD, during a session on C. difficile toxin testing at the Peggy Lillis Foundation 2022 National C. diff Advocacy Summit.

Dr. Lyerly, the chief science officer at Techlab, explained that exotoxins A and B are produced by specific strains of C. difficile and are involved in infections, but some patients who test positive for these toxins by polymerase chain reaction or other tests do not have CDI or they are not appropriate candidates for CDI treatment.

Several studies conducted during the past decade, however, support the importance of toxin detection. Some research has suggested that toxin-positive patients tend to have more clinically severe disease than those who test negative, he noted.

Although its use is limited when it is used alone, toxin testing is needed to confirm a CDI diagnosis and to ensure antibiotic stewardship, Dr. Lyerly said.

He suggested that, in addition to toxin testing, there is a need for molecular measures and other improved diagnostics to identify candidates most likely to benefit from CDI treatment.

“Because we generally detect toxin genes instead of toxin proteins, you can identify persons colonized with toxigenic C. difficile who do not actually have CDI,” Kevin W. Garey, PharmD, from the University of Houston, said in an interview.

Dr. Garey added that a person could likewise have low levels of toxins that aren’t detected by toxin tests but could still have CDI.

“Given this, better diagnostics that incorporate active toxin production and your body’s response to those toxins are needed,” he said, especially since C. difficile toxins are responsible for disease sequelae, including gastroenteritis, colonic perforation, sepsis, and death.
 

Toxin testing a ‘controversial area’

“C. difficile toxin testing has been a controversial area for almost a decade or more,” Shruti K. Gohil, MD, from University of California, Irvine, Health Epidemiology and Infection Prevention, said in an interview.

Dr. Gohil noted that toxin testing is a better test for clinical C. difficile colitis but by itself can miss C. difficile. “So, we are in this conundrum nationally,” she said.

“Many facilities will use a double- or triple-test strategy to make sure that you have a true C. difficile case mandating the use of antibiotics,” she explained. “The reason we test specifically with the enzyme immunoassay or toxin test is to know whether or not you have real C. difficile that’s actively producing the toxin for colitis.”

A patient with C. difficile who has been treated and is in recovery may still test positive on a C. difficile toxin test, added Dr. Gohil. “It would be great if we had a test that could really judge an active, clinical C. difficile infection. This [test] would help in identifying the right patients who need treatment and would also be able to tell if a patient has been cleared of C. difficile.”

Dr. Lyerly is an employee of Techlab. Dr. Garey and Dr. Gohil reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Clostridioides difficile infection is often confirmed through toxin testing, yet toxin tests alone may not be sufficient for diagnosing and guiding treatment decisions for patients with CDI.

“The presence of a toxigenic strain does not always equal disease,” said David Lyerly, PhD, during a session on C. difficile toxin testing at the Peggy Lillis Foundation 2022 National C. diff Advocacy Summit.

Dr. Lyerly, the chief science officer at Techlab, explained that exotoxins A and B are produced by specific strains of C. difficile and are involved in infections, but some patients who test positive for these toxins by polymerase chain reaction or other tests do not have CDI or they are not appropriate candidates for CDI treatment.

Several studies conducted during the past decade, however, support the importance of toxin detection. Some research has suggested that toxin-positive patients tend to have more clinically severe disease than those who test negative, he noted.

Although its use is limited when it is used alone, toxin testing is needed to confirm a CDI diagnosis and to ensure antibiotic stewardship, Dr. Lyerly said.

He suggested that, in addition to toxin testing, there is a need for molecular measures and other improved diagnostics to identify candidates most likely to benefit from CDI treatment.

“Because we generally detect toxin genes instead of toxin proteins, you can identify persons colonized with toxigenic C. difficile who do not actually have CDI,” Kevin W. Garey, PharmD, from the University of Houston, said in an interview.

Dr. Garey added that a person could likewise have low levels of toxins that aren’t detected by toxin tests but could still have CDI.

“Given this, better diagnostics that incorporate active toxin production and your body’s response to those toxins are needed,” he said, especially since C. difficile toxins are responsible for disease sequelae, including gastroenteritis, colonic perforation, sepsis, and death.
 

Toxin testing a ‘controversial area’

“C. difficile toxin testing has been a controversial area for almost a decade or more,” Shruti K. Gohil, MD, from University of California, Irvine, Health Epidemiology and Infection Prevention, said in an interview.

Dr. Gohil noted that toxin testing is a better test for clinical C. difficile colitis but by itself can miss C. difficile. “So, we are in this conundrum nationally,” she said.

“Many facilities will use a double- or triple-test strategy to make sure that you have a true C. difficile case mandating the use of antibiotics,” she explained. “The reason we test specifically with the enzyme immunoassay or toxin test is to know whether or not you have real C. difficile that’s actively producing the toxin for colitis.”

A patient with C. difficile who has been treated and is in recovery may still test positive on a C. difficile toxin test, added Dr. Gohil. “It would be great if we had a test that could really judge an active, clinical C. difficile infection. This [test] would help in identifying the right patients who need treatment and would also be able to tell if a patient has been cleared of C. difficile.”

Dr. Lyerly is an employee of Techlab. Dr. Garey and Dr. Gohil reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

Clostridioides difficile infection is often confirmed through toxin testing, yet toxin tests alone may not be sufficient for diagnosing and guiding treatment decisions for patients with CDI.

“The presence of a toxigenic strain does not always equal disease,” said David Lyerly, PhD, during a session on C. difficile toxin testing at the Peggy Lillis Foundation 2022 National C. diff Advocacy Summit.

Dr. Lyerly, the chief science officer at Techlab, explained that exotoxins A and B are produced by specific strains of C. difficile and are involved in infections, but some patients who test positive for these toxins by polymerase chain reaction or other tests do not have CDI or they are not appropriate candidates for CDI treatment.

Several studies conducted during the past decade, however, support the importance of toxin detection. Some research has suggested that toxin-positive patients tend to have more clinically severe disease than those who test negative, he noted.

Although its use is limited when it is used alone, toxin testing is needed to confirm a CDI diagnosis and to ensure antibiotic stewardship, Dr. Lyerly said.

He suggested that, in addition to toxin testing, there is a need for molecular measures and other improved diagnostics to identify candidates most likely to benefit from CDI treatment.

“Because we generally detect toxin genes instead of toxin proteins, you can identify persons colonized with toxigenic C. difficile who do not actually have CDI,” Kevin W. Garey, PharmD, from the University of Houston, said in an interview.

Dr. Garey added that a person could likewise have low levels of toxins that aren’t detected by toxin tests but could still have CDI.

“Given this, better diagnostics that incorporate active toxin production and your body’s response to those toxins are needed,” he said, especially since C. difficile toxins are responsible for disease sequelae, including gastroenteritis, colonic perforation, sepsis, and death.
 

Toxin testing a ‘controversial area’

“C. difficile toxin testing has been a controversial area for almost a decade or more,” Shruti K. Gohil, MD, from University of California, Irvine, Health Epidemiology and Infection Prevention, said in an interview.

Dr. Gohil noted that toxin testing is a better test for clinical C. difficile colitis but by itself can miss C. difficile. “So, we are in this conundrum nationally,” she said.

“Many facilities will use a double- or triple-test strategy to make sure that you have a true C. difficile case mandating the use of antibiotics,” she explained. “The reason we test specifically with the enzyme immunoassay or toxin test is to know whether or not you have real C. difficile that’s actively producing the toxin for colitis.”

A patient with C. difficile who has been treated and is in recovery may still test positive on a C. difficile toxin test, added Dr. Gohil. “It would be great if we had a test that could really judge an active, clinical C. difficile infection. This [test] would help in identifying the right patients who need treatment and would also be able to tell if a patient has been cleared of C. difficile.”

Dr. Lyerly is an employee of Techlab. Dr. Garey and Dr. Gohil reported no relevant financial relationships.

A version of this article first appeared on Medscape.com.

The benefit of endovascular therapy in the treatment of stroke caused by an occlusion of the basilar artery has finally been confirmed in the ATTENTION randomized trial.

The study, conducted in China, showed that endovascular therapy for basilar artery occlusion is associated with higher rates of favorable and independent outcomes, as well as lower overall disability and lower mortality at 90 days, than best medical management alone.

The results were presented by Raul Nogueira, MD, professor of neurology at the University of Pittsburgh School of Medicine, at the European Stroke Organisation Conference (ESOC) 2022, where they were greeted with applause from the audience.

The number needed to treat was just four.

“There were no surprises with secondary endpoints; everything was highly statistically significant,” Dr. Nogueira said.

Specifically, there was a lower rate of overall disability in the shift analysis, with a common odds ratio of 2.8 favoring the intervention.  

Safety results showed an increased risk for symptomatic ICH in the endovascular group (5.3% vs. 0.0%) but, despite that, 90-day mortality was significantly lower in the endovascular group (36.7% vs. 55.3%).

Dr. Nogueira noted a limitation of the study was that it was conducted in China.

“This was a Chinese study and, as Asians are known to have higher rates of intracranial atherosclerotic disease, the overall degree of generalizability of our findings to Western countries needs to be considered,” he commented.

However, subgroup analysis showed no treatment effect modification based on the presence of intracranial atherosclerotic disease, he noted.

Also, the proportion of comorbidities in the ATTENTION trial was similar to that in the BASICS trial, with the same degree of diabetes and atrial fibrillation.

Dr. Nogueira concluded that, in contrast to previous randomized trials of endovascular treatment for basilar artery occlusion, the ATTENTION trial was able to reinforce consecutive enrollment, resulting in a fast recruitment while minimizing crossovers. 

Furthermore, he pointed out that the overall results are consistent with modern era observational studies, large registries, and meta-analysis.

Commenting on the study, Joanna Wardlaw, MD, professor of applied neuroimaging at the University of Edinburgh (Scotland), and chair of the ESOC Planning Group, said: “This is a very important result, since it provides confirmation beyond doubt the benefit of thrombectomy versus medical therapy for basilar artery occlusion stroke up to 12 hours after onset.”

Dr. Wardlaw added: “The trial was large enough to provide clear results and to enable subgroup analyses; no subgroup did not benefit from thrombectomy.”

In a discussion after the presentation, Urs Fischer, MD, chair of the department of neurology at the University Hospital Basel, Switzerland, said he was not surprised by the results of the ATTENTION trial.

“We have been doing thrombectomy in patients with basilar artery occlusion now for 20 years, although trials are extremely important to answer these questions, so now we have some clear evidence,” Dr. Fischer said. “Nevertheless, there are some caveats, as this is an Asian population, but this is a proof of concept, and it is going in the right direction.”

The ATTENTION trial was sponsored by the First Affiliated Hospital of University of Science and Technology of China.

A version of this article first appeared on Medscape.com.

The benefit of endovascular therapy in the treatment of stroke caused by an occlusion of the basilar artery has finally been confirmed in the ATTENTION randomized trial.

The study, conducted in China, showed that endovascular therapy for basilar artery occlusion is associated with higher rates of favorable and independent outcomes, as well as lower overall disability and lower mortality at 90 days, than best medical management alone.

The results were presented by Raul Nogueira, MD, professor of neurology at the University of Pittsburgh School of Medicine, at the European Stroke Organisation Conference (ESOC) 2022, where they were greeted with applause from the audience.

The number needed to treat was just four.

“There were no surprises with secondary endpoints; everything was highly statistically significant,” Dr. Nogueira said.

Specifically, there was a lower rate of overall disability in the shift analysis, with a common odds ratio of 2.8 favoring the intervention.  

Safety results showed an increased risk for symptomatic ICH in the endovascular group (5.3% vs. 0.0%) but, despite that, 90-day mortality was significantly lower in the endovascular group (36.7% vs. 55.3%).

Dr. Nogueira noted a limitation of the study was that it was conducted in China.

“This was a Chinese study and, as Asians are known to have higher rates of intracranial atherosclerotic disease, the overall degree of generalizability of our findings to Western countries needs to be considered,” he commented.

However, subgroup analysis showed no treatment effect modification based on the presence of intracranial atherosclerotic disease, he noted.

Also, the proportion of comorbidities in the ATTENTION trial was similar to that in the BASICS trial, with the same degree of diabetes and atrial fibrillation.

Dr. Nogueira concluded that, in contrast to previous randomized trials of endovascular treatment for basilar artery occlusion, the ATTENTION trial was able to reinforce consecutive enrollment, resulting in a fast recruitment while minimizing crossovers. 

Furthermore, he pointed out that the overall results are consistent with modern era observational studies, large registries, and meta-analysis.

Commenting on the study, Joanna Wardlaw, MD, professor of applied neuroimaging at the University of Edinburgh (Scotland), and chair of the ESOC Planning Group, said: “This is a very important result, since it provides confirmation beyond doubt the benefit of thrombectomy versus medical therapy for basilar artery occlusion stroke up to 12 hours after onset.”

Dr. Wardlaw added: “The trial was large enough to provide clear results and to enable subgroup analyses; no subgroup did not benefit from thrombectomy.”

In a discussion after the presentation, Urs Fischer, MD, chair of the department of neurology at the University Hospital Basel, Switzerland, said he was not surprised by the results of the ATTENTION trial.

“We have been doing thrombectomy in patients with basilar artery occlusion now for 20 years, although trials are extremely important to answer these questions, so now we have some clear evidence,” Dr. Fischer said. “Nevertheless, there are some caveats, as this is an Asian population, but this is a proof of concept, and it is going in the right direction.”

The ATTENTION trial was sponsored by the First Affiliated Hospital of University of Science and Technology of China.

A version of this article first appeared on Medscape.com.

The benefit of endovascular therapy in the treatment of stroke caused by an occlusion of the basilar artery has finally been confirmed in the ATTENTION randomized trial.

The study, conducted in China, showed that endovascular therapy for basilar artery occlusion is associated with higher rates of favorable and independent outcomes, as well as lower overall disability and lower mortality at 90 days, than best medical management alone.

The results were presented by Raul Nogueira, MD, professor of neurology at the University of Pittsburgh School of Medicine, at the European Stroke Organisation Conference (ESOC) 2022, where they were greeted with applause from the audience.

The number needed to treat was just four.

“There were no surprises with secondary endpoints; everything was highly statistically significant,” Dr. Nogueira said.

Specifically, there was a lower rate of overall disability in the shift analysis, with a common odds ratio of 2.8 favoring the intervention.  

Safety results showed an increased risk for symptomatic ICH in the endovascular group (5.3% vs. 0.0%) but, despite that, 90-day mortality was significantly lower in the endovascular group (36.7% vs. 55.3%).

Dr. Nogueira noted a limitation of the study was that it was conducted in China.

“This was a Chinese study and, as Asians are known to have higher rates of intracranial atherosclerotic disease, the overall degree of generalizability of our findings to Western countries needs to be considered,” he commented.

However, subgroup analysis showed no treatment effect modification based on the presence of intracranial atherosclerotic disease, he noted.

Also, the proportion of comorbidities in the ATTENTION trial was similar to that in the BASICS trial, with the same degree of diabetes and atrial fibrillation.

Dr. Nogueira concluded that, in contrast to previous randomized trials of endovascular treatment for basilar artery occlusion, the ATTENTION trial was able to reinforce consecutive enrollment, resulting in a fast recruitment while minimizing crossovers. 

Furthermore, he pointed out that the overall results are consistent with modern era observational studies, large registries, and meta-analysis.

Commenting on the study, Joanna Wardlaw, MD, professor of applied neuroimaging at the University of Edinburgh (Scotland), and chair of the ESOC Planning Group, said: “This is a very important result, since it provides confirmation beyond doubt the benefit of thrombectomy versus medical therapy for basilar artery occlusion stroke up to 12 hours after onset.”

Dr. Wardlaw added: “The trial was large enough to provide clear results and to enable subgroup analyses; no subgroup did not benefit from thrombectomy.”

In a discussion after the presentation, Urs Fischer, MD, chair of the department of neurology at the University Hospital Basel, Switzerland, said he was not surprised by the results of the ATTENTION trial.

“We have been doing thrombectomy in patients with basilar artery occlusion now for 20 years, although trials are extremely important to answer these questions, so now we have some clear evidence,” Dr. Fischer said. “Nevertheless, there are some caveats, as this is an Asian population, but this is a proof of concept, and it is going in the right direction.”

The ATTENTION trial was sponsored by the First Affiliated Hospital of University of Science and Technology of China.

A version of this article first appeared on Medscape.com.

A new study finds clinicians are shifting away from the U.S. Food and Drug Administration–approved combination of warfarin and aspirin after left atrial appendage occlusion (LAAO) with the Watchman device and that adverse events, particularly bleeding, are lower when aspirin is dropped.

Of 31,994 patients successfully implanted with the Watchman 2.5 device in the 3 years after its March 2015 approval, only 1 in 10 received the full postprocedure protocol studied in pivotal trials and codified into the FDA-device approval.

The protocol consisted of aspirin (81-325 mg) indefinitely and warfarin for 45 days. Following transesophageal echocardiography, patients were then maintained on warfarin and aspirin if there was a peridevice leak greater than 5 mm or switched to clopidogrel 75 mg for 6 months if a peridevice leak was ruled out or was 5 mm or less.

Based on the results, drawn from the National Cardiovascular Data Registry (NCDR) LAAO Registry, the most common discharge medications were warfarin and aspirin in 36.9% of patients, followed by a direct oral anticoagulant (DOAC) and aspirin (20.8%), warfarin alone (13.5%), DOAC only (12.3%), and dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor (5%).

“There’s a little bit of practice leading the science in this space,” lead author James V. Freeman, MD, MPH, Yale School of Medicine, New Haven, Conn., told this news organization.

Patients who couldn’t tolerate long-term anticoagulation were excluded from the pivotal trials but are now the patients in whom the device is most often used, because of the Centers for Medicare & Medicaid reimbursement mandate for a relative or absolute contraindication to long-term anticoagulation, he noted.

Not surprisingly, 70% of patients in the registry had history of clinically relevant bleeding, the mean CHA2DS2-VASc score was 4.6, and mean HAS-BLED score was 3. At an average age of 76, they were also older, by years, than those in the clinical trials.

Secular trends at the time also saw the ascendancy of the DOACs relative to warfarin, observed Dr. Freeman. “So I think it’s pretty reasonable for physicians to be considering DOACs rather than warfarin in this context.”
 

Aspirin takes another hit

Results, published May 2 in the Journal of the American College of Cardiology, showed that any adverse event occurred at 45 days in 5.7% of patients discharged on warfarin and aspirin, 4% on warfarin alone, 5.2% on DOAC and aspirin, 3.8% on DOAC only, and 5.5% on DAPT.

Rates of any major adverse event were 4.4%, 3.3%, 4.3%, 3.1%, and 4.2% respectively, and for major bleeding were 3%, 1.8%, 2.8%, 1.7%, and 2.2% respectively. Although patients were similar across treatment groups, those treated with DAPT were slightly older and had more comorbidities, Dr. Freeman said.

In Cox frailty regression, the adjusted risk of any adverse event at 45 days was significantly lower when patients were discharged on warfarin alone (hazard ratio, 0.692; 95% confidence interval, 0.56-0.84) and a DOAC alone (HR, 0.731; 95% CI, 0.57-0.93), compared with warfarin and aspirin. There were no differences among the other groups.

The risk of any major adverse event was also significantly lower with warfarin alone (HR, 0.658; 95% CI, 0.53-0.80) and DOAC alone (HR, 0.767; 95% CI, 0.59-0.98).

At 6 months, rates of any adverse event (HR, 0.814; 95% CI, 0.72-0.93) and any major adverse event (HR, 0.840; 95% CI, 0.73-0.95) were significantly lower only in patients treated with warfarin alone.

“I think if there’s a take-home [message] here, it’s that for a lot of patients there’s good data now to suggest getting rid of the aspirin is a very reasonable thing to do,” Dr. Freeman said.

Further studies are needed in the space, but the results are consistent with those from transcatheter aortic valve replacement studies showing discharge on warfarin or DOAC anticoagulation alone reduces major adverse events without increasing thrombotic events, he said.

“I do think if there’s a strong indication for aspirin – someone has terrible coronary disease – there may be a role for using it,” Dr. Freeman said. But for a lot of these patients, anticoagulation alone without aspirin “may present a big opportunity to mitigate morbidity associated with this procedure.”

Dr. Freeman said he doesn’t expect the findings would be dramatically different with the second-generation Watchman FLX device but noted that randomized data will be forthcoming, as Boston Scientific changed the CHAMPION-AF trial protocol to include DOAC alone without aspirin.

Commenting for this news organization, Domenico Della Rocca, MD, Texas Cardiac Arrhythmia Institute at St. David’s Medical Center, Austin, said the study is a useful overview of post-LAAO therapies in a large population – but not surprising.

“Practice has changed over the years. More and more we are adopting and trusting the DOACs,” he said. “And, we are realizing that dual antiplatelet therapy is so aggressive and antiplatelet therapy alone maybe is not the best choice based on data on activation of coagulation.”

Commenting further, he said “I think it’s too early to suggest being too keen to completely drop aspirin,” noting that 20%-25% of patients have clopidogrel resistance and that the combination of two antiplatelets may be too aggressive a strategy for others.

Dr. Della Rocca and colleagues recently reported favorable long-term results with half-dose DOAC therapy after Watchman implantation and said the team is launching a randomized trial in more than 500 LAAO patients in the United States and Europe later this year. The trial will be comparing a DOAC-based strategy with low-dose apixaban long-term versus clopidogrel and aspirin initially and then switching to 100 mg aspirin long-term.

“We hope that in the next 2-3 years we will have some better answers, but at this point I would say that clopidogrel is kind of an obsolete strategy for appendage closure,” Dr. Della Rocca said.

In an accompanying editorial, David R. Holmes Jr., MD, Mayo Clinic, Rochester, Minn., says “the cornucopia of these specific strategies can be expected to change as practices evolve, as instructions for use broaden and, hopefully, with the results of well-done, scientifically performed trials. This current LAAO Registry report, however, serves as a useful benchmark.”

He cautioned that this is an observational cohort study and that unmeasured imbalances still may affect the ability to identify an unbiased treatment signal. The use of DAPT was also infrequent during the study and “conclusions based on this information are soft.”

The study was funded by the American College of Cardiology National Cardiovascular Data Registry (NCDR), and the National Heart, Lung, and Blood Institute (NHLBI) grants. Dr. Freeman has received salary support from the ACC NCDR and the NHLBI and has received consulting/advisory board fees from Boston Scientific, Medtronic, Janssen Pharmaceuticals, and Biosense Webster.

A version of this article first appeared on Medscape.com.

A new study finds clinicians are shifting away from the U.S. Food and Drug Administration–approved combination of warfarin and aspirin after left atrial appendage occlusion (LAAO) with the Watchman device and that adverse events, particularly bleeding, are lower when aspirin is dropped.

Of 31,994 patients successfully implanted with the Watchman 2.5 device in the 3 years after its March 2015 approval, only 1 in 10 received the full postprocedure protocol studied in pivotal trials and codified into the FDA-device approval.

The protocol consisted of aspirin (81-325 mg) indefinitely and warfarin for 45 days. Following transesophageal echocardiography, patients were then maintained on warfarin and aspirin if there was a peridevice leak greater than 5 mm or switched to clopidogrel 75 mg for 6 months if a peridevice leak was ruled out or was 5 mm or less.

Based on the results, drawn from the National Cardiovascular Data Registry (NCDR) LAAO Registry, the most common discharge medications were warfarin and aspirin in 36.9% of patients, followed by a direct oral anticoagulant (DOAC) and aspirin (20.8%), warfarin alone (13.5%), DOAC only (12.3%), and dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor (5%).

“There’s a little bit of practice leading the science in this space,” lead author James V. Freeman, MD, MPH, Yale School of Medicine, New Haven, Conn., told this news organization.

Patients who couldn’t tolerate long-term anticoagulation were excluded from the pivotal trials but are now the patients in whom the device is most often used, because of the Centers for Medicare & Medicaid reimbursement mandate for a relative or absolute contraindication to long-term anticoagulation, he noted.

Not surprisingly, 70% of patients in the registry had history of clinically relevant bleeding, the mean CHA2DS2-VASc score was 4.6, and mean HAS-BLED score was 3. At an average age of 76, they were also older, by years, than those in the clinical trials.

Secular trends at the time also saw the ascendancy of the DOACs relative to warfarin, observed Dr. Freeman. “So I think it’s pretty reasonable for physicians to be considering DOACs rather than warfarin in this context.”
 

Aspirin takes another hit

Results, published May 2 in the Journal of the American College of Cardiology, showed that any adverse event occurred at 45 days in 5.7% of patients discharged on warfarin and aspirin, 4% on warfarin alone, 5.2% on DOAC and aspirin, 3.8% on DOAC only, and 5.5% on DAPT.

Rates of any major adverse event were 4.4%, 3.3%, 4.3%, 3.1%, and 4.2% respectively, and for major bleeding were 3%, 1.8%, 2.8%, 1.7%, and 2.2% respectively. Although patients were similar across treatment groups, those treated with DAPT were slightly older and had more comorbidities, Dr. Freeman said.

In Cox frailty regression, the adjusted risk of any adverse event at 45 days was significantly lower when patients were discharged on warfarin alone (hazard ratio, 0.692; 95% confidence interval, 0.56-0.84) and a DOAC alone (HR, 0.731; 95% CI, 0.57-0.93), compared with warfarin and aspirin. There were no differences among the other groups.

The risk of any major adverse event was also significantly lower with warfarin alone (HR, 0.658; 95% CI, 0.53-0.80) and DOAC alone (HR, 0.767; 95% CI, 0.59-0.98).

At 6 months, rates of any adverse event (HR, 0.814; 95% CI, 0.72-0.93) and any major adverse event (HR, 0.840; 95% CI, 0.73-0.95) were significantly lower only in patients treated with warfarin alone.

“I think if there’s a take-home [message] here, it’s that for a lot of patients there’s good data now to suggest getting rid of the aspirin is a very reasonable thing to do,” Dr. Freeman said.

Further studies are needed in the space, but the results are consistent with those from transcatheter aortic valve replacement studies showing discharge on warfarin or DOAC anticoagulation alone reduces major adverse events without increasing thrombotic events, he said.

“I do think if there’s a strong indication for aspirin – someone has terrible coronary disease – there may be a role for using it,” Dr. Freeman said. But for a lot of these patients, anticoagulation alone without aspirin “may present a big opportunity to mitigate morbidity associated with this procedure.”

Dr. Freeman said he doesn’t expect the findings would be dramatically different with the second-generation Watchman FLX device but noted that randomized data will be forthcoming, as Boston Scientific changed the CHAMPION-AF trial protocol to include DOAC alone without aspirin.

Commenting for this news organization, Domenico Della Rocca, MD, Texas Cardiac Arrhythmia Institute at St. David’s Medical Center, Austin, said the study is a useful overview of post-LAAO therapies in a large population – but not surprising.

“Practice has changed over the years. More and more we are adopting and trusting the DOACs,” he said. “And, we are realizing that dual antiplatelet therapy is so aggressive and antiplatelet therapy alone maybe is not the best choice based on data on activation of coagulation.”

Commenting further, he said “I think it’s too early to suggest being too keen to completely drop aspirin,” noting that 20%-25% of patients have clopidogrel resistance and that the combination of two antiplatelets may be too aggressive a strategy for others.

Dr. Della Rocca and colleagues recently reported favorable long-term results with half-dose DOAC therapy after Watchman implantation and said the team is launching a randomized trial in more than 500 LAAO patients in the United States and Europe later this year. The trial will be comparing a DOAC-based strategy with low-dose apixaban long-term versus clopidogrel and aspirin initially and then switching to 100 mg aspirin long-term.

“We hope that in the next 2-3 years we will have some better answers, but at this point I would say that clopidogrel is kind of an obsolete strategy for appendage closure,” Dr. Della Rocca said.

In an accompanying editorial, David R. Holmes Jr., MD, Mayo Clinic, Rochester, Minn., says “the cornucopia of these specific strategies can be expected to change as practices evolve, as instructions for use broaden and, hopefully, with the results of well-done, scientifically performed trials. This current LAAO Registry report, however, serves as a useful benchmark.”

He cautioned that this is an observational cohort study and that unmeasured imbalances still may affect the ability to identify an unbiased treatment signal. The use of DAPT was also infrequent during the study and “conclusions based on this information are soft.”

The study was funded by the American College of Cardiology National Cardiovascular Data Registry (NCDR), and the National Heart, Lung, and Blood Institute (NHLBI) grants. Dr. Freeman has received salary support from the ACC NCDR and the NHLBI and has received consulting/advisory board fees from Boston Scientific, Medtronic, Janssen Pharmaceuticals, and Biosense Webster.

A version of this article first appeared on Medscape.com.

A new study finds clinicians are shifting away from the U.S. Food and Drug Administration–approved combination of warfarin and aspirin after left atrial appendage occlusion (LAAO) with the Watchman device and that adverse events, particularly bleeding, are lower when aspirin is dropped.

Of 31,994 patients successfully implanted with the Watchman 2.5 device in the 3 years after its March 2015 approval, only 1 in 10 received the full postprocedure protocol studied in pivotal trials and codified into the FDA-device approval.

The protocol consisted of aspirin (81-325 mg) indefinitely and warfarin for 45 days. Following transesophageal echocardiography, patients were then maintained on warfarin and aspirin if there was a peridevice leak greater than 5 mm or switched to clopidogrel 75 mg for 6 months if a peridevice leak was ruled out or was 5 mm or less.

Based on the results, drawn from the National Cardiovascular Data Registry (NCDR) LAAO Registry, the most common discharge medications were warfarin and aspirin in 36.9% of patients, followed by a direct oral anticoagulant (DOAC) and aspirin (20.8%), warfarin alone (13.5%), DOAC only (12.3%), and dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor (5%).

“There’s a little bit of practice leading the science in this space,” lead author James V. Freeman, MD, MPH, Yale School of Medicine, New Haven, Conn., told this news organization.

Patients who couldn’t tolerate long-term anticoagulation were excluded from the pivotal trials but are now the patients in whom the device is most often used, because of the Centers for Medicare & Medicaid reimbursement mandate for a relative or absolute contraindication to long-term anticoagulation, he noted.

Not surprisingly, 70% of patients in the registry had history of clinically relevant bleeding, the mean CHA2DS2-VASc score was 4.6, and mean HAS-BLED score was 3. At an average age of 76, they were also older, by years, than those in the clinical trials.

Secular trends at the time also saw the ascendancy of the DOACs relative to warfarin, observed Dr. Freeman. “So I think it’s pretty reasonable for physicians to be considering DOACs rather than warfarin in this context.”
 

Aspirin takes another hit

Results, published May 2 in the Journal of the American College of Cardiology, showed that any adverse event occurred at 45 days in 5.7% of patients discharged on warfarin and aspirin, 4% on warfarin alone, 5.2% on DOAC and aspirin, 3.8% on DOAC only, and 5.5% on DAPT.

Rates of any major adverse event were 4.4%, 3.3%, 4.3%, 3.1%, and 4.2% respectively, and for major bleeding were 3%, 1.8%, 2.8%, 1.7%, and 2.2% respectively. Although patients were similar across treatment groups, those treated with DAPT were slightly older and had more comorbidities, Dr. Freeman said.

In Cox frailty regression, the adjusted risk of any adverse event at 45 days was significantly lower when patients were discharged on warfarin alone (hazard ratio, 0.692; 95% confidence interval, 0.56-0.84) and a DOAC alone (HR, 0.731; 95% CI, 0.57-0.93), compared with warfarin and aspirin. There were no differences among the other groups.

The risk of any major adverse event was also significantly lower with warfarin alone (HR, 0.658; 95% CI, 0.53-0.80) and DOAC alone (HR, 0.767; 95% CI, 0.59-0.98).

At 6 months, rates of any adverse event (HR, 0.814; 95% CI, 0.72-0.93) and any major adverse event (HR, 0.840; 95% CI, 0.73-0.95) were significantly lower only in patients treated with warfarin alone.

“I think if there’s a take-home [message] here, it’s that for a lot of patients there’s good data now to suggest getting rid of the aspirin is a very reasonable thing to do,” Dr. Freeman said.

Further studies are needed in the space, but the results are consistent with those from transcatheter aortic valve replacement studies showing discharge on warfarin or DOAC anticoagulation alone reduces major adverse events without increasing thrombotic events, he said.

“I do think if there’s a strong indication for aspirin – someone has terrible coronary disease – there may be a role for using it,” Dr. Freeman said. But for a lot of these patients, anticoagulation alone without aspirin “may present a big opportunity to mitigate morbidity associated with this procedure.”

Dr. Freeman said he doesn’t expect the findings would be dramatically different with the second-generation Watchman FLX device but noted that randomized data will be forthcoming, as Boston Scientific changed the CHAMPION-AF trial protocol to include DOAC alone without aspirin.

Commenting for this news organization, Domenico Della Rocca, MD, Texas Cardiac Arrhythmia Institute at St. David’s Medical Center, Austin, said the study is a useful overview of post-LAAO therapies in a large population – but not surprising.

“Practice has changed over the years. More and more we are adopting and trusting the DOACs,” he said. “And, we are realizing that dual antiplatelet therapy is so aggressive and antiplatelet therapy alone maybe is not the best choice based on data on activation of coagulation.”

Commenting further, he said “I think it’s too early to suggest being too keen to completely drop aspirin,” noting that 20%-25% of patients have clopidogrel resistance and that the combination of two antiplatelets may be too aggressive a strategy for others.

Dr. Della Rocca and colleagues recently reported favorable long-term results with half-dose DOAC therapy after Watchman implantation and said the team is launching a randomized trial in more than 500 LAAO patients in the United States and Europe later this year. The trial will be comparing a DOAC-based strategy with low-dose apixaban long-term versus clopidogrel and aspirin initially and then switching to 100 mg aspirin long-term.

“We hope that in the next 2-3 years we will have some better answers, but at this point I would say that clopidogrel is kind of an obsolete strategy for appendage closure,” Dr. Della Rocca said.

In an accompanying editorial, David R. Holmes Jr., MD, Mayo Clinic, Rochester, Minn., says “the cornucopia of these specific strategies can be expected to change as practices evolve, as instructions for use broaden and, hopefully, with the results of well-done, scientifically performed trials. This current LAAO Registry report, however, serves as a useful benchmark.”

He cautioned that this is an observational cohort study and that unmeasured imbalances still may affect the ability to identify an unbiased treatment signal. The use of DAPT was also infrequent during the study and “conclusions based on this information are soft.”

The study was funded by the American College of Cardiology National Cardiovascular Data Registry (NCDR), and the National Heart, Lung, and Blood Institute (NHLBI) grants. Dr. Freeman has received salary support from the ACC NCDR and the NHLBI and has received consulting/advisory board fees from Boston Scientific, Medtronic, Janssen Pharmaceuticals, and Biosense Webster.

A version of this article first appeared on Medscape.com.