SAN DIEGO – For middle-aged men with diabetes, odds of erectile dysfunction are 50-50 at 50: By the age of 50, a full half will have the condition.

This isn’t normal for men of that age, according to Hunter B. Wessells, MD.“It’s not just that they’re aging. It’s a 20-year acceleration of the aging process,” he said at the annual scientific sessions of the American Diabetes Association.

That’s not all. In some cases, men with diabetes may experience decreased libido that’s potentially caused by low testosterone, said Dr. Wessells, professor and Wilma Wise Nelson, Ole A. Nelson, and Mabel Wise Nelson Endowed Chair in Urology at the University of Washington, Seattle

Women with diabetes also suffer from higher levels of sexual dysfunction, and their conditions can be even more difficult to treat.

Still, research findings offer useful insights into the frequency of sexual dysfunction in people with diabetes and the potential – and limitations – of available treatments, said Dr. Wessells.

In patients with well-controlled diabetes, “these conditions impact quality of life to a greater degree than complications like nephropathy, neuropathy, and retinopathy,” he said in an interview. “Thus, treatment of urological symptoms can be a high-yield endeavor.”

In both sexes, Dr. Wessells said, diabetes can disrupt the mechanism of desire, arousal, and orgasm by affecting a long list of bodily functions such as central nervous system stimulation, hormone activity, autonomic and somatic nerve activity, and processing of calcium ions and nitric acid.

In men, diabetes boosts the risk of erectile dysfunction to a larger extent than do related conditions such as obesity, heart disease, and depression. “But they are interrelated,” he said. “The primary mechanisms include the metabolic effects of high glucose, autonomic nerve damage, and microvascular disease.”

Low testosterone levels also can cause problems in patients with diabetes, he said. “Type 2 diabetes has greater effects on testosterone than type 1. It is most closely linked to weight in the type 1 population and affects only a small percentage.”

A 2017 systematic review and meta-analysis of 145 studies with more than 88,000 subjects (average age 55.8 ± 7.9 years) suggests that ED was more common in type 2 diabetes (66.3%) than type 1 diabetes (37.5%) after statistical adjustment to account for publication bias (Diabet Med. 2017 Jul 18. doi: 10.1111/dme.13403).

A smaller analysis found that men with diabetes had almost four times the odds (odd ratio = 3.62) of ED compared with healthy controls (Diabet Med. 2017 Jul 18. doi: 10.1111/dme.13403). Phosphodiesterase-5 inhibitors – such as sildenafil, vardenafil, and tadalafil – are one option for men with diabetes and ED, Dr. Wessells said. “They work pretty well, but men with diabetes tend to have more severe ED. They’re going to get better, but will they get better enough to be normal? That’s the question.”

A 2007 Cochrane Library analysis found that men with diabetes and ED gained from PDE5 inhibitors overall (Cochrane Database Syst Rev. 2007 Jan 24[1]:CD002187. doi: 10.1002/14651858.CD002187.pub3).

“They’re not going to do as well as the general population,” Dr. Wessells said, “but we should try these as first-line agents in absence of things like severe unstable cardiovascular disease and other risk factors.”

Second-line therapies, typically offered by urologists, include penile prostheses and injection therapy, he said. A 2014 analysis of previous research found that men with diabetes were “more than 50% more likely to be prescribed secondary ED treatments over the 2-year observation period, and more than twice as likely to undergo penile prosthesis surgery” (Int J Impot Res. 2014 May-Jun;26[3]:112-5).

As for women, a 2009 study found that of 424 sexually active women with type 1 diabetes (97% of whom were white), 35% showed signs of female sexual dysfunction (FSD). Of those with FSD, problems included loss of libido (57%); problems with orgasm (51%), lubrication (47%), and/or arousal (38%); and pain (21%) (Diabetes Care. 2009 May;32[5]:780-5).

Only one drug, flibanserin (Addyi), is approved for FSD in the United States. Its impact on patients with diabetes is unknown, Dr. Wessells said, and the drug has the potential for significant adverse events.

The good news: Research is providing insight into which men and women are more likely to develop sexual dysfunction, Dr. Wessells said.

Age is important in both genders. For women, depression and being married appear to be risk factors, he said. “This needs more exploration to help us understand how to intervene.”

And in men, he said, ED is linked to jumps in hemoglobin A_1c, while men on intensive glycemic therapy have a lower risk.

“Maybe we can find out who needs to be targeted for earlier intervention,” he said. This is especially important for men because ED becomes more likely to be irreversible after just a few years, he said.

Dr. Wessells reports no relevant disclosures.

Risk of sexual dysfunction in diabetes is high, but treatments can help