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The mask-and-hose contraption known as a CPAP machine may not look alluring, but the relief it provides for sleep apnea can help improve erectile dysfunction and boost users' sex lives.

A CPAP device, the Darth Vader-like mask used to ease breathing in sleep apnea sufferers, might be the least attractive thing a man can wear at night, but it could wind up improving his sex life, according to a new study released today at an annual meeting of sleep experts.

In yet another example of how the human penis can serve as an important health indicator, a team of doctors from the Sleep Disorders Center of the Walter Reed National Military Medical Center has found that erectile dysfunction is common in younger men with sleep apnea, but that E.D. -- and libido -- improves in men who use the CPAP, or continuous positive airway pressure machine.

They presented their results today at the meeting of the Associated Professional Sleep Societies in Boston.

Over the past few years, medical science has repeatedly shown that how a man’s penis is working can reflect how the rest of his body is working. E.D. can be an early sign of diabetes, cardiovascular disease, high blood pressure and poor fitness, among other ailments.

So when army captain Dr. Joseph Dombrowsky looked at a small handful of studies that had linked apnea to E.D., he realized that he had access to a pool of possible test subjects -- military beneficiaries newly diagnosed with the sleep disorder -- that he could use to explore the link.

Dombrowsky and his colleagues recruited 92 men with an average age of nearly 46 who had both a new diagnosis of obstructive sleep apnea, or OSA, and who were starting therapy with CPAP machines.

The CPAP is a mask-and-tube contraption that few might call sexy. Worn during sleep, it sends a steady flow of air through the mask into breathing passages to keep airways open and restore depleted oxygen levels. It’s the most common and effective treatment for OSA, which occurs when tissue in the back of the throat collapses during sleep, blocking air, disrupting sleep and boosting the risk of health problems such as heart disease and stroke.

The men in the study averaged 38 apnea events per hour, Dombrowsky found. That’s pretty bad. Severe apnea is defined as 30 or more such events per hour.

Using a well-established sexual function survey, 43.5 percent of the men reported erectile dysfunction. Unlike previous studies, the E.D. was broken down into three varieties: mild, moderate and severe. The men were reassessed at one-, three- and six-months of CPAP therapy. 

Dombrowksy was looking for what he called “minimal clinically important differences” of CPAP use.

“That’s not just a change in a score, a statistic,” he explained in an interview, “but a difference patients really notice and will appreciate.” 

More than half of patients with mild E.D., or some 54 percent, noticed an improvement after CPAP use. Nearly 29 percent of those with moderate E.D. improved, and more than 27 percent of those with severe E.D. saw a boost. Sexual desire also tended to improve, Dombrowsky found.

Drugs like Viagra have been shown to work more powerfully to improve E.D. than CPAP therapy, but  Dombrowsky speculates that by starting CPAP before the condition gets worse, some men might be able to skip the pills. 

While stressing that he was speaking for himself, not for his research team, the army, or the U.S. government, Dombrowsky said he believes that CPAP therapy might be a good early therapy for E.D., particularly in younger men.

“What the results say to me is that E.D. is a progressive disease, as is sleep apnea. So if we were to intervene earlier, we might be able to stave off the progression of erectile dysfunction.”

His study raises the issue of why apnea might lead to E.D. in the first place. The most obvious explanation is that the link is related to the way apnea creates low oxygen levels in the blood. But that may or may not be correct. Dombrowsky pointed out that during REM sleep, men get erections in something like a nocturnal workout of penis plumbing. Because apnea interferes with REM sleep, fragmenting sleep patterns, penises may not be getting this workout, leading to dysfunction.

Dombrowksy said he plans to continue the work with larger numbers of men in hopes of answering some of these questions.         

Brian Alexander (www.BrianRAlexander.com) is co-author, with Larry Young PhD., of "The Chemistry Between Us: Love Sex and the Science of Attraction," (www.TheChemistryBetweenUs.com)  to be published Sept. 13.

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