Sleep apnea may cause weight gain

SEATTLE, June 12 (UPI) -- U.S. researchers say they have found a link between weight gain and the sleep disorder obstructive sleep apnea.

Study lead author Dr. Mark Brown of the University of Arizona College of Medicine in Tucson says people suffering from more severe obstructive sleep apnea may be more likely to gain more weight over time than those with less severe apnea.

"Obstructive sleep apnea 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 obstructive sleep apnea itself may predispose patients to weight gain," Brown said in a statement.

The researchers measured the severity of the disease using the apnea-hypopnea index based on the total number of complete breathing cessations -- apnea -- and partial obstructions -- hypopnea. They found those with an apnea-hypopnea index of more than 15 were more likely to have a greater body mass index than those with an index between 5 and 15.

The study included data from 3,001 men and women. The final model used for calculations in the study was adjusted for age, gender, race, initial body mass index and change in apnea-hypopnea index over five years.

The findings were presented at Sleep, the annual meeting of the Associated Professional Sleep Societies in Seattle.