MONDAY, June 6 (HealthDay News) -- Many people who suffer from obstructive sleep apnea could eliminate the condition by losing a significant amount of weight, a new study suggests.

Without realizing it, people with sleep apnea wake up multiple times throughout the night as they struggle to breathe. The condition can cause severe daytime tiredness and other symptoms. In many cases, patients are treated with continuous positive airway pressure (CPAP), a treatment that uses a machine to keep their airways open during sleep.

According to Dr. Virend Somers, a professor of medicine and cardiovascular diseases at the Mayo Clinic in Rochester, Minn., there seems to be a connection between sleep apnea and extra pounds. But exactly how they're related is not exactly clear, he said. "Although the majority of patients are obese, not everyone with sleep apnea is obese," said Somers, who was not involved with the new study.

Physicians do know that "as you gain weight, sleep apnea gets worse, and as you lose, it improves," Somers noted. Obesity may affect the airway's ability to stay open during sleep, or extra fat cells could affect the brain's control of the airway, he suggested.

In the new study, published online June 1 in BMJ, researchers led by Kari Johansson of the Karolinska Institute in Stockholm tracked 63 male sleep apnea patients, aged 30 to 65, who were overweight. Of those, 58 completed a version of the Cambridge Weight Plan, which started with a very low-calorie diet for nine weeks, followed by a year-long program of weight-maintenance counseling. The Cambridge Weight Plan provided partial funding for the study.

After a year, about half of the patients who lost weight and kept it off no longer needed a CPAP machine to keep their airways open during sleep, and sleep apnea went away in 10 percent of them.

Somers noted that it's unlikely that the specific diet approach itself was important. "I'm not aware of any interaction between what you eat and sleep apnea," he said. Instead, it's likely that simply losing weight did the trick, he explained.

More information

For more about sleep apnea, visit the U.S. National Library of Medicine.