Sleep-Disordered Breathing More Likely in Obese Inpatients

Sleep-disordered breathing in hospitalized patients is more common in those who are obese and those who have heart failure.

“There may be more [sleep-disordered breathing] in hospitalized patients than has been recognized,” concluded Dr. Kim Goring and Dr. Nancy Collop, of Johns Hopkins University Hospital and Bayview Medical Center, both in Baltimore.

“There is a need for a higher clinical suspicion, especially in patients with underlying cardiopulmonary disease,” the researchers said.

In a chart review of 94 inpatients referred for polysomnography at two tertiary care facilities, a body mass index (BMI) of 40 kg/m

The patients (51 women, 43 men) were admitted to Johns Hopkins or Bayview between January 2003 and September 2004 for acute illnesses, mostly chronic obstructive pulmonary disease or heart failure; the next most common diagnoses were interstitial lung disease, acute pulmonary embolism, and pulmonary hypertension.

The mean age of the participants was 54 years (range, 20–82 years), and their mean BMI was 40 (range, 18–70). Of the total sample, 86% were obese (BMI greater than 30), the researchers reported.

The patients underwent overnight polysomnography to detect sleep apnea (defined as complete or almost complete cessation of airflow—less than 25% of baseline—lasting 10 seconds or longer) and hypopnea (defined as a fall in oxygen saturation of at least 4%, or an arousal from sleep). An apnea-hypopnea index (AHI) greater than 10 was classified as sleep-disordered breathing (J. Clin. Sleep Med. 2008;4:105–10).

Of the 94 patients, 77% had sleep-disordered breathing, and of those with the condition, 95% had obstructive sleep apnea.

“This high prevalence of [sleep-disordered breathing] is most likely due to the overwhelming influence of obesity,” Dr. Goring and Dr. Collop wrote. They found “a statistically significant increase in the [odds ratio] of sleep apnea with every unit increase in BMI” after adjusting for all other variables, with the vast majority of the study patients with a BMI over 40 positive for sleep apnea.

Weight has been shown to strongly predict sleep-disordered breathing. In this study, “there was a probable bias on the part of the referring physicians in targeting obese patients for inpatient polysomnography, given that 86% of those referred were obese.”

Although 60% of normal-weight patients with interstitial lung disease, neuromuscular disease, or acute pulmonary embolism had sleep-disordered breathing, it was difficult to draw statistically significant conclusions because of the small numbers of subjects, they wrote.

The association between sleep apnea and heart failure was significant, but the investigators cited difficulty in assessing the effect of obesity on the likelihood of sleep-disordered breathing in patients with heart failure.

No link was found between sleep apnea and any of the other acute illnesses in these patients.

The study was supported by grants from the National Institutes of Health. Neither researcher had a financial conflict of interest.

Sleep-disordered breathing in hospitalized patients is more common in those who are obese and those who have heart failure.

“There may be more [sleep-disordered breathing] in hospitalized patients than has been recognized,” concluded Dr. Kim Goring and Dr. Nancy Collop, of Johns Hopkins University Hospital and Bayview Medical Center, both in Baltimore.

“There is a need for a higher clinical suspicion, especially in patients with underlying cardiopulmonary disease,” the researchers said.

In a chart review of 94 inpatients referred for polysomnography at two tertiary care facilities, a body mass index (BMI) of 40 kg/m

The patients (51 women, 43 men) were admitted to Johns Hopkins or Bayview between January 2003 and September 2004 for acute illnesses, mostly chronic obstructive pulmonary disease or heart failure; the next most common diagnoses were interstitial lung disease, acute pulmonary embolism, and pulmonary hypertension.

The mean age of the participants was 54 years (range, 20–82 years), and their mean BMI was 40 (range, 18–70). Of the total sample, 86% were obese (BMI greater than 30), the researchers reported.

The patients underwent overnight polysomnography to detect sleep apnea (defined as complete or almost complete cessation of airflow—less than 25% of baseline—lasting 10 seconds or longer) and hypopnea (defined as a fall in oxygen saturation of at least 4%, or an arousal from sleep). An apnea-hypopnea index (AHI) greater than 10 was classified as sleep-disordered breathing (J. Clin. Sleep Med. 2008;4:105–10).

Of the 94 patients, 77% had sleep-disordered breathing, and of those with the condition, 95% had obstructive sleep apnea.

“This high prevalence of [sleep-disordered breathing] is most likely due to the overwhelming influence of obesity,” Dr. Goring and Dr. Collop wrote. They found “a statistically significant increase in the [odds ratio] of sleep apnea with every unit increase in BMI” after adjusting for all other variables, with the vast majority of the study patients with a BMI over 40 positive for sleep apnea.

Weight has been shown to strongly predict sleep-disordered breathing. In this study, “there was a probable bias on the part of the referring physicians in targeting obese patients for inpatient polysomnography, given that 86% of those referred were obese.”

Although 60% of normal-weight patients with interstitial lung disease, neuromuscular disease, or acute pulmonary embolism had sleep-disordered breathing, it was difficult to draw statistically significant conclusions because of the small numbers of subjects, they wrote.

The association between sleep apnea and heart failure was significant, but the investigators cited difficulty in assessing the effect of obesity on the likelihood of sleep-disordered breathing in patients with heart failure.

No link was found between sleep apnea and any of the other acute illnesses in these patients.

The study was supported by grants from the National Institutes of Health. Neither researcher had a financial conflict of interest.

Sleep-disordered breathing in hospitalized patients is more common in those who are obese and those who have heart failure.

“There may be more [sleep-disordered breathing] in hospitalized patients than has been recognized,” concluded Dr. Kim Goring and Dr. Nancy Collop, of Johns Hopkins University Hospital and Bayview Medical Center, both in Baltimore.

“There is a need for a higher clinical suspicion, especially in patients with underlying cardiopulmonary disease,” the researchers said.

In a chart review of 94 inpatients referred for polysomnography at two tertiary care facilities, a body mass index (BMI) of 40 kg/m

The patients (51 women, 43 men) were admitted to Johns Hopkins or Bayview between January 2003 and September 2004 for acute illnesses, mostly chronic obstructive pulmonary disease or heart failure; the next most common diagnoses were interstitial lung disease, acute pulmonary embolism, and pulmonary hypertension.

The mean age of the participants was 54 years (range, 20–82 years), and their mean BMI was 40 (range, 18–70). Of the total sample, 86% were obese (BMI greater than 30), the researchers reported.

The patients underwent overnight polysomnography to detect sleep apnea (defined as complete or almost complete cessation of airflow—less than 25% of baseline—lasting 10 seconds or longer) and hypopnea (defined as a fall in oxygen saturation of at least 4%, or an arousal from sleep). An apnea-hypopnea index (AHI) greater than 10 was classified as sleep-disordered breathing (J. Clin. Sleep Med. 2008;4:105–10).

Of the 94 patients, 77% had sleep-disordered breathing, and of those with the condition, 95% had obstructive sleep apnea.

“This high prevalence of [sleep-disordered breathing] is most likely due to the overwhelming influence of obesity,” Dr. Goring and Dr. Collop wrote. They found “a statistically significant increase in the [odds ratio] of sleep apnea with every unit increase in BMI” after adjusting for all other variables, with the vast majority of the study patients with a BMI over 40 positive for sleep apnea.

Weight has been shown to strongly predict sleep-disordered breathing. In this study, “there was a probable bias on the part of the referring physicians in targeting obese patients for inpatient polysomnography, given that 86% of those referred were obese.”

Although 60% of normal-weight patients with interstitial lung disease, neuromuscular disease, or acute pulmonary embolism had sleep-disordered breathing, it was difficult to draw statistically significant conclusions because of the small numbers of subjects, they wrote.

The association between sleep apnea and heart failure was significant, but the investigators cited difficulty in assessing the effect of obesity on the likelihood of sleep-disordered breathing in patients with heart failure.

No link was found between sleep apnea and any of the other acute illnesses in these patients.

The study was supported by grants from the National Institutes of Health. Neither researcher had a financial conflict of interest.