Impotence in Diabetes: The Neurologic Factor

This study was undertaken to elucidate the factor(s) underlying the frequent occurrence of impotence in diabetic men. A neurogenic basis was suspected because potency depends on the autonomic nervous system, which is frequently involved in diabetic neuropathy. Since the nerves concerned with potency and micturition are identical, neurogenic bladder studies were performed. Of 45 impotent diabetics with an average age of 43.2 years, 37 had neurogenic vesical abnormalities, and 38 had neuropathy. Of 30 potent diabetics with an average age of 42.7 years, only 3 had bladder involvement, and 6 had neuropathy. A random survey of 200 diabetic men showed 59% to be impotent; 82% of these had neuropathy. Of the 41% who were potent, 12% had neuropathy. This was unrelated to severity or duration of diabetes. To evaluate a possible endocrine role, plasma testosterone levels were measured and found to be normal. Therapeutic trials with testosterone were without benefit. The results imply a significant neuropathic factor in diabetic impotence and minimize an endocrine basis.