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Losing Your Mind Trying to Understand the BP-Dementia Link
You could be forgiven if you are confused about how blood pressure (BP) affects dementia. First, you read an article extolling the benefits of BP lowering, then a study about how stopping antihypertensives slows cognitive decline in nursing home residents. It’s enough to make you lose your mind.
The Brain Benefits of BP Lowering
It should be stated unequivocally that you should absolutely treat high BP. It may have once been acceptable to state, “The greatest danger to a man with high blood pressure lies in its discovery, because then some fool is certain to try and reduce it.” But those dark days are long behind us.
In these divided times, at least we can agree that we should treat high BP. The cardiovascular (CV) benefits, in and of themselves, justify the decision. But BP’s relationship with dementia is more complex. There are different types of dementia even though we tend to lump them all into one category. Vascular dementia is driven by the same pathophysiology and risk factors as cardiac disease. It’s intuitive that treating hypertension, diabetes, hypercholesterolemia, and smoking will decrease the risk for stroke and limit the damage to the brain that we see with repeated vascular insults. For Alzheimer’s disease, high BP and other CV risk factors seem to increase the risk even if the mechanism is not fully elucidated.
Estimates suggest that if we could lower the prevalence of hypertension by 25%, there would be 160,000 fewer cases of Alzheimer’s disease. But the data are not as robust as one might hope. A 2021 Cochrane review found that hypertension treatment slowed cognitive decline, but the quality of the evidence was low. Short duration of follow-up, dropouts, crossovers, and other problems with the data precluded any certainty. What’s more, hypertension in midlife is associated with cognitive decline and dementia, but its impact in those over age 70 is less clear. Later in life, or once cognitive impairment has already developed, it may be too late for BP lowering to have any impact.
Potential Harms of Lowering BP
All this needs to be weighed against the potential harms of treating hypertension. I will reiterate that hypertension should be treated and treated aggressively for the prevention of CV events. But overtreatment, especially in older patients, is associated with hypotension, falls, and syncope. Older patients are also at risk for polypharmacy and drug-drug interactions.
A Korean nationwide survey showed a U-shaped association between BP and Alzheimer’s disease risk in adults (mean age, 67 years), with both high and low BPs associated with a higher risk for Alzheimer’s disease. Though not all studies agree. A post hoc analysis of SPRINT MIND did not find any negative impact of intensive BP lowering on cognitive outcomes or cerebral perfusion in older adults (mean age, 68 years). But it didn’t do much good either. Given the heterogeneity of the data, doubts remain on whether aggressive BP lowering might be detrimental in older patients with comorbidities and preexisting dementia. The obvious corollary then is whether deprescribing hypertensive medications could be beneficial.
A recent publication in JAMA Internal Medicine attempted to address this very question. The cohort study used data from Veterans Affairs nursing home residents (mean age, 78 years) to emulate a randomized trial on deprescribing antihypertensives and cognitive decline. Many of the residents’ cognitive scores worsened over the course of follow-up; however, the decline was less pronounced in the deprescribing group (10% vs 12%). The same group did a similar analysis looking at CV outcomes and found no increased risk for heart attack or stroke with deprescribing BP medications. Taken together, these nursing home data suggest that deprescribing may help slow cognitive decline without the expected trade-off of increased CV events.
Deprescribing, Yes or No?
However, randomized data would obviously be preferable, and these are in short supply. One such trial, the DANTE study, found no benefit to deprescribing in terms of cognition in adults aged 75 years or older with mild cognitive impairment. The study follow-up was only 16 weeks, however, which is hardly enough time to demonstrate any effect, positive or negative. The most that can be said is that it didn’t cause many short-term adverse events.
Perhaps the best conclusion to draw from this somewhat underwhelming collection of data is that lowering high BP is important, but less important the closer we get to the end of life. Hypotension is obviously bad, and overly aggressive BP lowering is going to lead to negative outcomes in older adults because gravity is an unforgiving mistress.
Deprescribing antihypertensives in older adults is probably not going to cause major negative outcomes, but whether it will do much good in nonhypotensive patients is debatable. The bigger problem is the millions of people with undiagnosed or undertreated hypertension. We would probably have less dementia if we treated hypertension when it does the most good: as a primary-prevention strategy in midlife.
Dr. Labos is a cardiologist at Hôpital Notre-Dame, Montreal, Quebec, Canada. He disclosed no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.
You could be forgiven if you are confused about how blood pressure (BP) affects dementia. First, you read an article extolling the benefits of BP lowering, then a study about how stopping antihypertensives slows cognitive decline in nursing home residents. It’s enough to make you lose your mind.
The Brain Benefits of BP Lowering
It should be stated unequivocally that you should absolutely treat high BP. It may have once been acceptable to state, “The greatest danger to a man with high blood pressure lies in its discovery, because then some fool is certain to try and reduce it.” But those dark days are long behind us.
In these divided times, at least we can agree that we should treat high BP. The cardiovascular (CV) benefits, in and of themselves, justify the decision. But BP’s relationship with dementia is more complex. There are different types of dementia even though we tend to lump them all into one category. Vascular dementia is driven by the same pathophysiology and risk factors as cardiac disease. It’s intuitive that treating hypertension, diabetes, hypercholesterolemia, and smoking will decrease the risk for stroke and limit the damage to the brain that we see with repeated vascular insults. For Alzheimer’s disease, high BP and other CV risk factors seem to increase the risk even if the mechanism is not fully elucidated.
Estimates suggest that if we could lower the prevalence of hypertension by 25%, there would be 160,000 fewer cases of Alzheimer’s disease. But the data are not as robust as one might hope. A 2021 Cochrane review found that hypertension treatment slowed cognitive decline, but the quality of the evidence was low. Short duration of follow-up, dropouts, crossovers, and other problems with the data precluded any certainty. What’s more, hypertension in midlife is associated with cognitive decline and dementia, but its impact in those over age 70 is less clear. Later in life, or once cognitive impairment has already developed, it may be too late for BP lowering to have any impact.
Potential Harms of Lowering BP
All this needs to be weighed against the potential harms of treating hypertension. I will reiterate that hypertension should be treated and treated aggressively for the prevention of CV events. But overtreatment, especially in older patients, is associated with hypotension, falls, and syncope. Older patients are also at risk for polypharmacy and drug-drug interactions.
A Korean nationwide survey showed a U-shaped association between BP and Alzheimer’s disease risk in adults (mean age, 67 years), with both high and low BPs associated with a higher risk for Alzheimer’s disease. Though not all studies agree. A post hoc analysis of SPRINT MIND did not find any negative impact of intensive BP lowering on cognitive outcomes or cerebral perfusion in older adults (mean age, 68 years). But it didn’t do much good either. Given the heterogeneity of the data, doubts remain on whether aggressive BP lowering might be detrimental in older patients with comorbidities and preexisting dementia. The obvious corollary then is whether deprescribing hypertensive medications could be beneficial.
A recent publication in JAMA Internal Medicine attempted to address this very question. The cohort study used data from Veterans Affairs nursing home residents (mean age, 78 years) to emulate a randomized trial on deprescribing antihypertensives and cognitive decline. Many of the residents’ cognitive scores worsened over the course of follow-up; however, the decline was less pronounced in the deprescribing group (10% vs 12%). The same group did a similar analysis looking at CV outcomes and found no increased risk for heart attack or stroke with deprescribing BP medications. Taken together, these nursing home data suggest that deprescribing may help slow cognitive decline without the expected trade-off of increased CV events.
Deprescribing, Yes or No?
However, randomized data would obviously be preferable, and these are in short supply. One such trial, the DANTE study, found no benefit to deprescribing in terms of cognition in adults aged 75 years or older with mild cognitive impairment. The study follow-up was only 16 weeks, however, which is hardly enough time to demonstrate any effect, positive or negative. The most that can be said is that it didn’t cause many short-term adverse events.
Perhaps the best conclusion to draw from this somewhat underwhelming collection of data is that lowering high BP is important, but less important the closer we get to the end of life. Hypotension is obviously bad, and overly aggressive BP lowering is going to lead to negative outcomes in older adults because gravity is an unforgiving mistress.
Deprescribing antihypertensives in older adults is probably not going to cause major negative outcomes, but whether it will do much good in nonhypotensive patients is debatable. The bigger problem is the millions of people with undiagnosed or undertreated hypertension. We would probably have less dementia if we treated hypertension when it does the most good: as a primary-prevention strategy in midlife.
Dr. Labos is a cardiologist at Hôpital Notre-Dame, Montreal, Quebec, Canada. He disclosed no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.
You could be forgiven if you are confused about how blood pressure (BP) affects dementia. First, you read an article extolling the benefits of BP lowering, then a study about how stopping antihypertensives slows cognitive decline in nursing home residents. It’s enough to make you lose your mind.
The Brain Benefits of BP Lowering
It should be stated unequivocally that you should absolutely treat high BP. It may have once been acceptable to state, “The greatest danger to a man with high blood pressure lies in its discovery, because then some fool is certain to try and reduce it.” But those dark days are long behind us.
In these divided times, at least we can agree that we should treat high BP. The cardiovascular (CV) benefits, in and of themselves, justify the decision. But BP’s relationship with dementia is more complex. There are different types of dementia even though we tend to lump them all into one category. Vascular dementia is driven by the same pathophysiology and risk factors as cardiac disease. It’s intuitive that treating hypertension, diabetes, hypercholesterolemia, and smoking will decrease the risk for stroke and limit the damage to the brain that we see with repeated vascular insults. For Alzheimer’s disease, high BP and other CV risk factors seem to increase the risk even if the mechanism is not fully elucidated.
Estimates suggest that if we could lower the prevalence of hypertension by 25%, there would be 160,000 fewer cases of Alzheimer’s disease. But the data are not as robust as one might hope. A 2021 Cochrane review found that hypertension treatment slowed cognitive decline, but the quality of the evidence was low. Short duration of follow-up, dropouts, crossovers, and other problems with the data precluded any certainty. What’s more, hypertension in midlife is associated with cognitive decline and dementia, but its impact in those over age 70 is less clear. Later in life, or once cognitive impairment has already developed, it may be too late for BP lowering to have any impact.
Potential Harms of Lowering BP
All this needs to be weighed against the potential harms of treating hypertension. I will reiterate that hypertension should be treated and treated aggressively for the prevention of CV events. But overtreatment, especially in older patients, is associated with hypotension, falls, and syncope. Older patients are also at risk for polypharmacy and drug-drug interactions.
A Korean nationwide survey showed a U-shaped association between BP and Alzheimer’s disease risk in adults (mean age, 67 years), with both high and low BPs associated with a higher risk for Alzheimer’s disease. Though not all studies agree. A post hoc analysis of SPRINT MIND did not find any negative impact of intensive BP lowering on cognitive outcomes or cerebral perfusion in older adults (mean age, 68 years). But it didn’t do much good either. Given the heterogeneity of the data, doubts remain on whether aggressive BP lowering might be detrimental in older patients with comorbidities and preexisting dementia. The obvious corollary then is whether deprescribing hypertensive medications could be beneficial.
A recent publication in JAMA Internal Medicine attempted to address this very question. The cohort study used data from Veterans Affairs nursing home residents (mean age, 78 years) to emulate a randomized trial on deprescribing antihypertensives and cognitive decline. Many of the residents’ cognitive scores worsened over the course of follow-up; however, the decline was less pronounced in the deprescribing group (10% vs 12%). The same group did a similar analysis looking at CV outcomes and found no increased risk for heart attack or stroke with deprescribing BP medications. Taken together, these nursing home data suggest that deprescribing may help slow cognitive decline without the expected trade-off of increased CV events.
Deprescribing, Yes or No?
However, randomized data would obviously be preferable, and these are in short supply. One such trial, the DANTE study, found no benefit to deprescribing in terms of cognition in adults aged 75 years or older with mild cognitive impairment. The study follow-up was only 16 weeks, however, which is hardly enough time to demonstrate any effect, positive or negative. The most that can be said is that it didn’t cause many short-term adverse events.
Perhaps the best conclusion to draw from this somewhat underwhelming collection of data is that lowering high BP is important, but less important the closer we get to the end of life. Hypotension is obviously bad, and overly aggressive BP lowering is going to lead to negative outcomes in older adults because gravity is an unforgiving mistress.
Deprescribing antihypertensives in older adults is probably not going to cause major negative outcomes, but whether it will do much good in nonhypotensive patients is debatable. The bigger problem is the millions of people with undiagnosed or undertreated hypertension. We would probably have less dementia if we treated hypertension when it does the most good: as a primary-prevention strategy in midlife.
Dr. Labos is a cardiologist at Hôpital Notre-Dame, Montreal, Quebec, Canada. He disclosed no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.
Walking 10,000 steps a day: Desirable goal or urban myth?
Some myths never die. The idea of taking 10,000 steps a day is one of them. What started as a catchy marketing slogan has become a mantra for anyone promoting physical activity.
It all began in 1965 when the Japanese company Yamasa Tokei began selling a new step-counter which they called manpo-kei (ten-thousand steps meter). They coupled the product launch with an ad campaign – “Let’s walk 10,000 steps a day!” – in a bid to encourage physical activity. The threshold was always somewhat arbitrary, but the idea of 10,000 steps cemented itself in the public consciousness from that point forward.
To be fair, there is nothing wrong with taking 10,000 steps a day, and it does roughly correlate with the generally recommended amount of physical activity. Most people will take somewhere between 5,000 and 7,500 steps a day even if they lead largely sedentary lives. If you add 30 minutes of walking to your daily routine, that will account for an extra 3,000-4,000 steps and bring you close to that 10,000-step threshold. As such, setting a 10,000-step target is a potentially useful shorthand for people aspiring to achieve ideal levels of physical activity.
But walking fewer steps still has a benefit. A study in JAMA Network Open followed a cohort of 2,110 adults from the CARDIA study and found, rather unsurprisingly, that those with more steps per day had lower rates of all-cause mortality. But interestingly, those who averaged 7,000-10,000 steps per day did just as well as those who walked more than 10,000 steps, suggesting that the lower threshold was probably the inflection point.
Other research has shown that improving your step count is probably more important than achieving any specific threshold. In one Canadian study, patients with diabetes were randomized to usual care or to an exercise prescription from their physicians. The intervention group improved their daily step count from around 5,000 steps per day to about 6,200 steps per day. While the increase was less than the researchers had hoped for, it still resulted in improvements in blood sugar control. In another study, a 24-week walking program reduced blood pressure by 11 points in postmenopausal women, even though their increased daily step counts fell shy of the 10,000 goal at about 9,000 steps. Similarly, a small Japanese study found that enrolling postmenopausal women in a weekly exercise program helped improve their lipid profile even though they only increased their daily step count from 6,800 to 8,500 steps per day. And an analysis of U.S. NHANES data showed a mortality benefit when individuals taking more than 8,000 steps were compared with those taking fewer than 4,000 steps per day. The benefits largely plateaued beyond 9,000-10,000 steps.
The reality is that walking 10,000 steps a day is a laudable goal and is almost certainly beneficial. But even lower levels of physical activity have benefits. The trick is not so much to aim for some theoretical ideal but to improve upon your current baseline. Encouraging patients to get into the habit of taking a daily walk (be it in the morning, during lunchtime, or in the evening) is going to pay dividends regardless of their daily step count. The point is that when it comes to physical activity, the greatest benefit seems to be when we go from doing nothing to doing something.
Dr. Labos is a cardiologist at Queen Elizabeth Health Complex, Montreal. He reported no conflicts of interest.
A version of this article first appeared on Medscape.com.
Some myths never die. The idea of taking 10,000 steps a day is one of them. What started as a catchy marketing slogan has become a mantra for anyone promoting physical activity.
It all began in 1965 when the Japanese company Yamasa Tokei began selling a new step-counter which they called manpo-kei (ten-thousand steps meter). They coupled the product launch with an ad campaign – “Let’s walk 10,000 steps a day!” – in a bid to encourage physical activity. The threshold was always somewhat arbitrary, but the idea of 10,000 steps cemented itself in the public consciousness from that point forward.
To be fair, there is nothing wrong with taking 10,000 steps a day, and it does roughly correlate with the generally recommended amount of physical activity. Most people will take somewhere between 5,000 and 7,500 steps a day even if they lead largely sedentary lives. If you add 30 minutes of walking to your daily routine, that will account for an extra 3,000-4,000 steps and bring you close to that 10,000-step threshold. As such, setting a 10,000-step target is a potentially useful shorthand for people aspiring to achieve ideal levels of physical activity.
But walking fewer steps still has a benefit. A study in JAMA Network Open followed a cohort of 2,110 adults from the CARDIA study and found, rather unsurprisingly, that those with more steps per day had lower rates of all-cause mortality. But interestingly, those who averaged 7,000-10,000 steps per day did just as well as those who walked more than 10,000 steps, suggesting that the lower threshold was probably the inflection point.
Other research has shown that improving your step count is probably more important than achieving any specific threshold. In one Canadian study, patients with diabetes were randomized to usual care or to an exercise prescription from their physicians. The intervention group improved their daily step count from around 5,000 steps per day to about 6,200 steps per day. While the increase was less than the researchers had hoped for, it still resulted in improvements in blood sugar control. In another study, a 24-week walking program reduced blood pressure by 11 points in postmenopausal women, even though their increased daily step counts fell shy of the 10,000 goal at about 9,000 steps. Similarly, a small Japanese study found that enrolling postmenopausal women in a weekly exercise program helped improve their lipid profile even though they only increased their daily step count from 6,800 to 8,500 steps per day. And an analysis of U.S. NHANES data showed a mortality benefit when individuals taking more than 8,000 steps were compared with those taking fewer than 4,000 steps per day. The benefits largely plateaued beyond 9,000-10,000 steps.
The reality is that walking 10,000 steps a day is a laudable goal and is almost certainly beneficial. But even lower levels of physical activity have benefits. The trick is not so much to aim for some theoretical ideal but to improve upon your current baseline. Encouraging patients to get into the habit of taking a daily walk (be it in the morning, during lunchtime, or in the evening) is going to pay dividends regardless of their daily step count. The point is that when it comes to physical activity, the greatest benefit seems to be when we go from doing nothing to doing something.
Dr. Labos is a cardiologist at Queen Elizabeth Health Complex, Montreal. He reported no conflicts of interest.
A version of this article first appeared on Medscape.com.
Some myths never die. The idea of taking 10,000 steps a day is one of them. What started as a catchy marketing slogan has become a mantra for anyone promoting physical activity.
It all began in 1965 when the Japanese company Yamasa Tokei began selling a new step-counter which they called manpo-kei (ten-thousand steps meter). They coupled the product launch with an ad campaign – “Let’s walk 10,000 steps a day!” – in a bid to encourage physical activity. The threshold was always somewhat arbitrary, but the idea of 10,000 steps cemented itself in the public consciousness from that point forward.
To be fair, there is nothing wrong with taking 10,000 steps a day, and it does roughly correlate with the generally recommended amount of physical activity. Most people will take somewhere between 5,000 and 7,500 steps a day even if they lead largely sedentary lives. If you add 30 minutes of walking to your daily routine, that will account for an extra 3,000-4,000 steps and bring you close to that 10,000-step threshold. As such, setting a 10,000-step target is a potentially useful shorthand for people aspiring to achieve ideal levels of physical activity.
But walking fewer steps still has a benefit. A study in JAMA Network Open followed a cohort of 2,110 adults from the CARDIA study and found, rather unsurprisingly, that those with more steps per day had lower rates of all-cause mortality. But interestingly, those who averaged 7,000-10,000 steps per day did just as well as those who walked more than 10,000 steps, suggesting that the lower threshold was probably the inflection point.
Other research has shown that improving your step count is probably more important than achieving any specific threshold. In one Canadian study, patients with diabetes were randomized to usual care or to an exercise prescription from their physicians. The intervention group improved their daily step count from around 5,000 steps per day to about 6,200 steps per day. While the increase was less than the researchers had hoped for, it still resulted in improvements in blood sugar control. In another study, a 24-week walking program reduced blood pressure by 11 points in postmenopausal women, even though their increased daily step counts fell shy of the 10,000 goal at about 9,000 steps. Similarly, a small Japanese study found that enrolling postmenopausal women in a weekly exercise program helped improve their lipid profile even though they only increased their daily step count from 6,800 to 8,500 steps per day. And an analysis of U.S. NHANES data showed a mortality benefit when individuals taking more than 8,000 steps were compared with those taking fewer than 4,000 steps per day. The benefits largely plateaued beyond 9,000-10,000 steps.
The reality is that walking 10,000 steps a day is a laudable goal and is almost certainly beneficial. But even lower levels of physical activity have benefits. The trick is not so much to aim for some theoretical ideal but to improve upon your current baseline. Encouraging patients to get into the habit of taking a daily walk (be it in the morning, during lunchtime, or in the evening) is going to pay dividends regardless of their daily step count. The point is that when it comes to physical activity, the greatest benefit seems to be when we go from doing nothing to doing something.
Dr. Labos is a cardiologist at Queen Elizabeth Health Complex, Montreal. He reported no conflicts of interest.
A version of this article first appeared on Medscape.com.