May 26, 2011

May 26, 2011 (Washington, DC) — Diabetic men are significantly more likely to require invasive second- and third-line therapies to manage erectile dysfunction (ED) than nondiabetic men, including surgical intervention, according to results of a study reported here at the American Urological Association (AUA) 2011 Annual Scientific Meeting.

Investigators reviewed information from a large medical-claims database and found that diabetic men were more than 50% more likely than nondiabetic men to progress to secondary therapies, such as penile suppositories or injectables, within 5 years of an ED diagnosis.

Diabetic men were also more than twice as likely to undergo tertiary therapy involving penile prosthesis surgery.

Dr. Thomas Walsh

"Our data show that men with diabetes have a more refractory treatment course [for ED] than nondiabetics," Thomas J. Walsh, MD, assistant professor of urology at the University of Washington School of Medicine in Seattle, told Medscape Medical News.

"This is a very robust dataset and a snapshot of the American population. We have an enormous pool of men treated over a 5-year period with very meticulous record-keeping," he said. "We know if they are diabetic, we know if they are nondiabetic, we know if they develop ED, and we know what they receive for ED treatment."

The Seattle team reviewed medical-claims data from 136,306 men identified from the Innovus i3 database, which has claims data for more than 30 million individuals in the United States who subscribe to United Health Care Insurance.

ED was defined by International Classification of Diseases (ICD)-9 coding or by pharmacy claims data showing treatment with an oral phosphodiesterase type 5 inhibitor.

A diagnosis of diabetes was confirmed by ICD-9 coding or documentation of diabetes-specific treatments.

The researchers compared rates of second-and third-line ED therapies in men with and without preexisting diabetes.

The analysis consisted of adult male subscribers who were identified as having prevalent and incident ED between January 1, 2002 and December 31, 2006.

In this group, 19,236 men had been diagnosed with diabetes before they were diagnosed with ED.

Results showed that diabetics were 1.6 times more likely than nondiabetics to progress to second-line therapies (95% confidence interval [CI], 1.4 to 1.7) and 2.1 times more likely to progress to third-line therapies (95% CI, 1.8 to 2.6) within 5 years of an ED. Progression to second- and third-line therapies was most dramatic within the first 6 months of an ED diagnosis.

The study also found that differences in the rates of primary treatment failures between men with and without diabetes increased over the 60 months of follow-up.

"Our results suggest that ED among diabetics may be less responsive to primary treatment with oral agents, more rapidly progressive than ED not associated with diabetes, or both," Dr. Walsh said.

He also pointed out that the study revealed, unexpectedly, that several men were prescribed ED medications that had not been "coded" for ED. "We found, surprisingly, that a certain contingent of men in our cohort were actually coded with ICD code 607.84 — which is very specific for men who have an organic cause for their ED — but many, many more men who were being prescribed medications like Viagra, Levitra, and Cialis did not have a code for ED. It's very clear that these men had ED, since men are not prescribed [these drugs] for anything other than ED."

He added: "What we recognize is that men are going in to see their primary care doctors and on the way out the door they are saying, 'By the way, I am having this problem. Do you think you could give me a prescription?' So I think we have a larger problem on our hands (i.e., ED is more common) than standardized coding is actually allowing us to detect. These patients are being treated with ED-specific medications but not being labeled as having ED."

Dr. Walsh said that future research should look at whether tighter diabetes control causes less progression to invasive treatments. Studies should also look at whether diabetes type or disease duration influences the need for more aggressive ED therapy.

Dr. Tobias Köhler

"This study shows that first-line therapies for ED in diabetics are often ineffective and that patients will have to go on to second- and third-line therapies if they truly want to be effectively treated for their ED," Tobias Köhler, MD, MPH, assistant professor of andrology at Southern Illinois University School of Medicine in Springfield, and AUA spokesperson, told Medscape Medical News.

"Erectile dysfunction worsens with poor diabetes control because of diabetes-related peripheral nerve damage and decreased blood flow to the penis," he said. "It's well known that when men improve their overall health with lifestyle changes, such as exercising more, eating a healthy diet, and stopping smoking — all the things we know we should do — their erections will get better. However, in diabetics, the odds are just a little more stacked against them for [lifestyle changes] to be effective. The same is true for pills, which are standard first-line therapy. Practitioners who treat diabetics need to know that there is less chance of success with first-line agents in diabetics, and that they probably need to progress to aggressive treatments earlier."

Finally, Dr. Köhler emphasized that it's important to remember that "good treatments are available for all patients and, depending on what the patient is willing to do, every man can get an erection if he sees a physician specializing in sexual dysfunction."

This study was performed in collaboration with the Urologic Diseases of America Project and was supported by the National Institute of Diabetes and Digestive and Kidney Diseases. Dr. Walsh and Dr. Köhler have disclosed no relevant financial relationships.

American Urological Association (AUA) 2011 Annual Scientific Meeting: Abstract 1329. Presented May 16, 2011.