Thursday, October 9, 2008

Obesity and Sleep Apnea: A New Chicken-and-Egg Paradox

We have mentioned several times that obesity puts people at significant risk for sleep apnea. Obese people have a much greater risk of suffering from obstructive sleep apnea than people of a more ideal body weight. But correlation doesn't equal causation, and there is some evidence that in some, many, or all cases, the causal arrow may point the other way.

In human beings, two hormones that have a powerful effect on appetite are leptin and ghrelin. It is more complicated than this, but in general leptin suppresses appetite, while ghrelin stimulates appetite. In studies, the level of both hormones were found to be correlated with low sleep levels. In fact, in a Wisconsin Sleep Cohort Study of 1024 individuals, shorter sleep time was found to correlate both with increased ghrelin levels and lower leptin levels. Since leptin also stimulates the body to burn energy, the combination of elevated ghrelin levels and reduced leptin levels will lead to decreased energy consumption and increased appetite, leading to higher levels of obesity. The study's only caveat is that because of the population it contained more snorers than the overall population.

Interestingly, not all studies have confirmed these results. Some have found sleep apnea sufferers have elevated levels of leptin, not ghrelin, while others suggest that sleep apnea sufferers seem to have elevated levels of both hormones. What is agreed by all the studies, however, is that sleep deficiencies can have a significant impact on the levels of these hormones. And there is evidence that sleep apnea treatment with CPAP can regulate the level of these hormones. It is likely that in cases where oral appliance treatment is called for, it will also help regulate these levels.

So if you are a sleep apnea sufferer who is overweight, it is possible that your apnea is the cause of your weight gain, not the other way around. And if you have been trying to lose weight but have so far been unsuccessful, it may be due to sleep apnea. If you would like to learn more about the possible benefits of sleep apnea treatment, contact the Snoring and Sleep Apnea Treatment Center in Gurnee, Illinois today to schedule your sleep apnea consultation.

http://www.ihateheadaches.org/