Losing weight through exercise and more-healthful eating may have long-term benefits for people with mild sleep apnea, a new study suggests.

Researchers found that obese study participants who went through a one-year lifestyle intervention were about half as likely to see their sleep apnea progress to more severe disease as were those who received little extra help.

People who have sleep apnea stop breathing for short spurts when their airway collapses or gets blocked while they’re asleep. The condition is most common among heavy, middle-aged adults; in its advanced form, it has been tied to a range of cardiovascular problems.

“It usually takes at least a few years to progress from mild disease to the more severe disease, and mostly it’s due to weight gain,” said Henri Tuomilehto, who led the study at a sleep clinic in Finland.

“With these results, we can say that if we change our lifestyle . . . we really can stop the progression of sleep apnea,” he said.

Tuomilehto and his colleagues randomly assigned 81 obese adults with mild sleep apnea either to a one-year intervention, which started with a very-low-calorie meal plan and included diet and exercise counseling, or to a comparison group that received only a few general diet and physical activity information sessions.

The study initially showed that there were health benefits tied to the intervention, Tuomilehto said. But whether the effects would persist was unclear.

For the new analysis, the researchers followed up with 57 of the initial participants four years after the experiment ended.

They found that people in the exercise and diet group had generally succeeded in keeping some weight off. Those participants were 12 pounds lighter than they had been five years earlier, on average, while people in the comparison group were about one pound heavier.

Six participants in the intervention group had seen their mild sleep apnea progress to moderate disease, and none had developed severe disease. Twelve members of the comparison group had moderate sleep apnea at their follow-up and two had severe sleep apnea, the researchers wrote in JAMA Internal Medicine.

“If you’ve lost some weight four years later, even if you’ve regained some, there’s still some significant benefit in terms of your apnea,” said Gary Foster, head of the Center for Obesity Research and Education at the Temple University School of Medicine in Philadelphia.

Foster, who did not work on the new study, said that the new finding is consistent with his own research in a larger group of patients with sleep apnea and diabetes.

“Obesity is the single most potent modifiable risk factor for obstructive sleep apnea,” he said.

“We should really think about weight reduction as a treatment for sleep apnea,” Tuomilehto agreed.

According to the American College of Physicians, 4 to 9 percent of middle-aged men and 2 to 4 percent of middle-aged women have sleep apnea, but the majority of cases are not diagnosed.

Continuous positive airway pressure, or CPAP — which helps keep the airways open at night — allows people to sleep better, but it hasn’t been shown to prevent cardiovascular problems tied to sleep apnea, Tuomilehto said. So weight loss is important even among people who are receiving standard treatment.

“Once you get some symptoms — even not that dramatic symptoms — then you should take the symptoms seriously, because in the early phases of the disease, if you change your lifestyle habits, you can cure the disease and prevent the progression of the disease,” he said.

— Reuters