Poorer diets seen in people with sleep apnea

By Amy Norton

NEW YORK (Reuters Health) - People with severe sleep apnea tend to eat a less healthy diet than people with milder apnea symptoms and those without the disorder, a new study suggests.

Obstructive sleep apnea, or OSA, occurs when the soft tissues at the back of the throat temporarily collapse during sleep, causing repeated breathing interruptions. Major symptoms include loud snoring and daytime sleepiness.

In the new study, researchers found that among 320 adults they assessed, those with severe symptoms of sleep apnea generally ate diets higher in cholesterol and artery-clogging saturated fat. While obesity does raise the risk of severe sleep apnea, the findings were not explained by the study participants' weight.

The results, say the researchers, suggest that eating habits may contribute to the increased risks of heart disease and stroke seen in people with sleep apnea.

"This unhealthy diet may be one reason why sleep apnea contributes to a greater risk of cardiovascular disease," senior researcher Dr. Stuart Quan, of Harvard Medical School in Boston, told Reuters Health.

He and his colleagues report their findings in the Journal of Clinical Sleep Medicine.

People with OSA have been found to have a higher risk of cardiovascular disease than those without the breathing disorder. Experts are not certain that this is a cause-and-effect relationship, but there are reasons to believe that OSA can directly lead to cardiovascular problems.

It's thought, for example, that repeated bouts of oxygen deprivation during sleep raise blood pressure, which takes a toll on the cardiovascular system over time.

The latest findings from Quan's team suggest that OSA may have indirect effects on the heart as well, via a less healthy lifestyle.

Among the patients assessed, those with severe OSA consumed an average of 9 extra grams of saturated fat and 88 extra milligrams of cholesterol per day compared with patients with mild symptoms or none at all.

Those with severe OSA also exercised less, but that link appeared to be explained by their higher rate of obesity. In contrast, the higher fat and cholesterol intakes were independent of patients' weight, Quan said.

He noted that the study also failed to show that poorer diet quality was related to the severity of patients' sleep deprivation; past research has suggested that sleep deprivation may upset the balance of certain appetite-controlling hormones.

More studies are needed, the researchers say, both to understand why severe OSA sufferers have fattier diets and whether this pattern helps explain their higher rate of cardiovascular disease.

SOURCE: Journal of Clinical Sleep Medicine, October 15, 2008.