According to a research abstract that will be presented on June11, at Sleep 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies, a link exists between the severity of obstructive sleep apnea (OSA) and weight gain.

Results indicate that people with an apnea-hypopnea index (AHI), the average of the combined episodes of apnea and hypopnea that occur per hour of sleep, of over 15 had an increase in body mass index (BMI) of 0.52 kg/m2 compared to those with an AHI between 5 and 15, who saw an increase of 0.22 kg/m2.

According to lead author Mark Brown, MD, Department of Psychiatry at the University of Arizona College of Medicine in Tucson, people suffering from more severe OSA may be more likely to gain more weight than those with less severe OSA over time.

"OSA is a disorder characterized by decreases or cessation of breathing during sleep. Obesity is a known risk factor for the disorder; however, it is hypothesized that the effects of OSA itself may predispose patients to weight gain," said Brown.

The study included data from 3,001 men and women from the Sleep Heart Health Study (SHHS) with an average age of 62.19. Of the sample, 55.2 percent of participants were female and 76.1 percent were Caucasian. Participants were classified as having no (AHI of less than 5), moderate (AHI between 5 and 15), and severe OSA (AHI of over 15). Weight and polysomnograph information were collected. Linear regression was used to examine the association between AHI groups and the change in BMI over approximately five years. The final model was adjusted for age, gender, race, initial BMI and change in AHI over 5 years.

Abstract Title: Sleep-Disorded Breathing and Weight Gain: The Sleep Heart Health Study.