Etiology of Diabetic Impotence

Abstract
Thirty-one male diabetics were evaluated for sexual dysfunction. Patients were examined by an endocrinologist, psychologist or psychiatrist, urologist and neurophysiologist. Evaluation was done by penile blood pressure, pudenal nerve latency, psychologic testing and laboratory tests, including serum testosterone levels. Mean patient age was 53 yr and the average onset of sexual dysfunction was 6 yr after the diagnosis of diabetes. Results showed that 68% of the patients had evidence of vascular occlusion, 26% had neurologic abnormalities, 19% had low plasma testosterone levels and 38% had relevant psychological problems, although the condition was considered primarily psychogenic in only 19%. Of those patients with abnormal nerve latencies, 86% had abnormal Doppler penile systolic pressures, while only 28% of the patients with abnormal penile pressures had abnormal neurologic findings. Apparently, vascular occlusion is the most prevalent abnormality in impotent diabetics and may predate neurologic abnormalities. The diabetics were divided into 2 groups, insulin-dependent and insulin-nondependent patients. A higher incidence of vascular lesions was found in insulin-dependent diabetics (83 vs. 57%), suggesting that vascular pathological conditions are related to severity of the diabetes. Although most diabetics have a vascular etiology for impotence, one must remember that other causes may be present and that a thorough investigation is necessary.