Diabetic Neuropathy Ups Erectile Dysfunction, Urinary Problems

Miriam E. Tucker

September 17, 2014

Erectile dysfunction and lower-urinary-tract symptoms are common among men with type 1 diabetes who have diabetic peripheral neuropathy (DPN), a new analysis finds.

The data, from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC), were presented September 13 at Neurodiab, the annual meeting of the Diabetic Neuropathy Study Group of the European Association for the Study of Diabetes, by Rodica Pop-Busui, MD, PhD, associate professor of internal medicine, metabolism, endocrinology, and diabetes and codirector of the Neuropathy Center at the University of Michigan, Ann Arbor. Dr. Pop-Busui also reported the results at the here at the European Association for the Study of Diabetes 2014 Meeting on September 17.

In all, Dr. Pop-Busui and colleagues found about a 4-fold increased prevalence of erectile dysfunction, nocturia, frequency, urgency, weak urinary stream, intermittency, straining, and/or the sensation of incomplete emptying among the men with type 1 diabetes and diabetic peripheral neuropathy compared with those without neuropathy.

"We believe that physicians should ask patients about all these complications....Both diabetic peripheral neuropathy and urologic complications have a major impact on the patients' quality of life," Dr. Pop-Busui told Medscape Medical News.

The EDIC study is the real-world follow-up to the landmark DCCT, in which patients with type 1 diabetes randomized to tight glycemic control had lower rates of retinopathy, neuropathy, and nephropathy compared with those who followed then-conventional treatment. Over time since DCCT's end, glycemic control of the 2 treatment groups has equalized.

"The key messages were that erectile dysfunction and lower-urinary-tract symptoms were highly prevalent even in those with previous tight control," Rayaz A. Malik, MD, professor of medicine and consultant physician at Weill Cornell Medical School, Qatar, and Central Manchester University Teaching Hospitals, United Kingdom, who was not involved in the study, told Medscape Medical News.

Symptoms Almost 4 Times More Likely in Those With Neuropathy

Study subjects were 635 men who had participated in DCCT and continue to be followed in EDIC. At the time of the current analysis, they had a mean age of 52 years and had had type 1 diabetes for 30 years, with a mean HbA1c of 7.9%.

Diabetic peripheral neuropathy was confirmed by a combination of symptoms and examination findings consistent with the condition and abnormal nerve-conduction studies.

Erectile dysfunction was defined by "very low/low" response to the International Index of Erectile Function question "Over the past 4 weeks, how would you rate your confidence that you can get and keep erection?" Lower-urinary-tract symptoms were defined by scores 8 to 35 on the American Urological Association Symptom Index.

Overall, 30% reported erectile dysfunction only, 10% reported lower-urinary-tract symptoms only, and 15% reported both. Among the men who had confirmed diabetic peripheral neuropathy, those proportions were 41%, 31%, and 62%, respectively (P < .0001).

After adjustment for age, DCCT group assignment (intensive vs conventional treatment), HbA1c, and blood pressure over both DCCT and EDIC study periods, as well as other variables, the odds ratio for having both erectile dysfunction and lower-urinary-tract symptoms was 3.82 for men with confirmed diabetic peripheral neuropathy compared with those without (95% confidence interval, 2.0–7.3).

"Novel" Findings

Dr. Pop-Busui told Medscape Medical News that this is the first time such data have been confirmed in a large sample of men with type 1 diabetes.

Although the results are intuitively not surprising, a clear confirmation has not actually been obtained before. Prior studies were smaller, did not adjust for confounders, or used insensitive measures and collection methods.

"This cohort of patients with type 1 diabetes has been followed for about 30 years and was carefully characterized for many other risk factors, including blood pressure, lipids, body mass index, smoking, and other diabetes complications. In addition, we used standardized, high-quality, and sensitive and specific evaluations for the outcomes of interest, so this is novel."

Moreover, she said of the current analysis, the magnitude of effect "is surprising."

Dr. Malik noted that the odds ratio of developing both erectile dysfunction and lower-urinary-tract symptoms was related to neuropathy defined by symptoms/signs and electrophysiology, but not by the Michigan Neuropathy Screening Instrument (MNSI), "suggesting that MNSI is a crude predictor of outcomes," he told Medscape Medical News.

Dr. Pop-Busui has received research funding from the National Institutes of Health, the American Diabetes Association, and Bristol-Myers Squibb. She is a consultant for AstraZeneca and Acorda Therapeutics. Dr. Malik has reported no relevant financial relationships.

Neurodiab; September 13, 2014; Sopron, Hungary. Abstract O-23.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.