An Unlikely Gateway to Men's Health

It is a subject few men are willing to broach, in the bedroom or the doctor's office. That's what makes Hopkins researchers' detailed findings on erectile dysfunction (ED), published in a February issue of The American Journal of Medicine, so revealing.

At first glance, the findings on ED—defined in this study as "sometimes able" or "never able" to have and maintain an erection—might seem discouraging. Researchers, led by Elizabeth Selvin, PhD, MPH, an Epidemiology assistant scientist, found that 18 million, or 18.4 percent, of all men in the United States 20 years or older suffer from ED. Researchers found that as men age, their risk for ED skyrockets. Among the study participants 70 years and older, the percentage suffering from ED reached 70.2 percent. The study drew data from 2,126 men who had participated in the 2001-2002 National Health and Nutrition Examination Survey.

Even more noteworthy than the discovery of ED's high incidence was its strong association with certain medical conditions. About half of the study subjects with ED also had diabetes or a history of cardiovascular disease; of the subjects considered obese (Body Mass Index over 30), 21.8 percent suffered from ED.

"These findings suggest that penile health may be a gateway to a man's overall health," says Arthur Burnett, MD, an investigator on the study and a professor of urology at the Johns Hopkins School of Medicine.

"The most surprising finding was the connection between [erectile dysfunction] and lack of physical activity. We saw a very strong association," notes Elizabeth Selvin.

Just as lifestyle changes can minimize the adverse effects of medical conditions like diabetes and cardiovascular disease, researchers learned they might have a positive impact on ED, too.

"The most surprising finding was the connection between ED and lack of physical activity. We saw a very strong association," based on subjects' self-reporting, says Selvin. Men who reported three or more hours of sedentary activity per day—measured by TV, video and/or computer use—were approximately three times more likely to have ED than subjects who reported less than one hour of sedentary activity each day.

The next step is to find out just what effect physical activity has on ED. To date, only one other study has linked lifestyle changes to ED incidence. In that 2004 Journal of the American Medical Association study, researchers discovered that one-third of obese men who reduced caloric intake and increased physical activity lost weight and improved sexual functioning.

While it's too soon to tell whether men with ED will be able to replace Viagra with more regular visits to the gym, preliminary findings suggest that may be the case. "There's definitely a need," says Selvin, "for an intervention study looking at the impact of lifestyle changes on ED."