NEW YORK (Reuters Health) - Wearing compression stockings during the day may slightly improve sleep apnea at night, a small study suggests.

The benefits of the knee-high socks, however, failed to convince sleep specialists that they’d hit on a new cure for obstructive sleep apnea, which is a potentially serious condition.

In obstructive sleep apnea, breathing repeatedly stops and starts during sleep because the airway becomes narrowed or blocked. The condition affects 12 million Americans, raising their risk of high blood pressure, heart attack, stroke, irregular heartbeat and diabetes. It also raises their risk of being sleepy and fatigued during the day, because they sleep poorly at night.

The gold-standard therapy for obstructive sleep apnea is a continuous positive airway pressure, or CPAP, device.

In the new study, 22 patients with obstructive sleep apnea who wore compression stockings during the day for two weeks saw their frequency of apneas decrease by 27 percent, compared to 23 patients who didn’t wear the stockings, Dr. T. Douglas Bradley and colleagues report in Sleep Medicine.

The authors call the 27 percent reduction “modest.” They say it reduced patients’ sleep apnea “from the severe to the moderate range.”

They did not, however, see any improvements in patients’ daytime alertness or sleepiness.

There are a number of reasons the airway may be blocked during sleep. For example, the throat muscles and tongue may relax, blocking the airway.

This new study points to another potential mechanism, Bradley told Reuters Health. He believes fluid can move from the legs into the neck, restrict the flow of oxygen and cause obstructive sleep apnea.

“Getting rid of excess fluid is one approach of treating sleep apnea,” said Bradley, a sleep specialist and professor at the University of Toronto.

Compression stockings, widely used to treat varicose veins and by workers whose jobs keep them on their feet all day, exert pressure on the legs and reduce fluid movement.

“This study highlights what we believe to be a new cause of sleep apnea,” Bradley said. “This is further evidence that it really is a mechanism that causes sleep apnea.”

But sleep specialist Dr. Jafari Behrouz of the University of California, Irvine, told Reuters Health he is not ready to prescribe the knee-highs to his apnea patients.

“At this point, I do not recommend stockings to treat sleep apnea,” said Behrouz, who was not involved with the current study.

The first thing he recommends for sleep apnea patients is that they improve their sleep hygiene by eliminating sedatives and alcohol for six hours before bedtime and by avoiding caffeine after lunch. He also advises that overweight patients try to lose weight and morbidly obese patients consider bariatric surgery.

He also recommends that patients use the gold-standard CPAP device when they sleep.

Some patients have trouble using it or do not like using it. A mouthpiece called a mandibular advancement device is an alternative that holds the lower jaw and tongue forward during sleep.

Snorers, especially men 50 years and older with a history of high blood pressure or stroke should talk to their doctors about their risk for sleep apnea, Behrouz said.

“The patient and physician can discuss what’s the best treatment for them,” he said. “For the majority of the patients, the best treatment still is the CPAP machine.”

SOURCE: http://bit.ly/1CNgJvf Sleep Medicine, online December 18, 2014.

(By Ronnie Cohen)