Erectile failure in the aged: evaluation and treatment.

With aging, there are changes in both libido and erectile function. Although the majority of aged men remain interested in sex, less than 15% report continued sexual intercourse. The cause of this "libido-potency gap" is due primarily to erectile failure. Penile erection is dependent upon a complex interaction of the autonomic nervous system, cardiovascular system, and local neurotransmitters such as acetylcholine and vasoactive intestinal polypeptide. Sexual stimulation causes augmented blood flow into the corpora cavernosa, and restricted outflow, resulting in penile rigidity. With aging, there is a decline in gonadal steroids, nerve conduction velocity, and vascular compliance, any of which could interfere with normal erections. When disease is superimposed on the normal changes of aging, erectile function is further impaired. Evaluation of an elderly male with impotence may consist of a detailed drug history and trial of alternate therapy, as in the case of adverse drug reactions. More often, evaluation entails hormonal assays, penile vascular assessment, neurologic assessment, and an evaluation of nocturnal erectile function. Based on the results of these assessments, appropriate treatment alternatives can be chosen. With the availability of multiple treatment options, patients and physicians can now choose from a range of noninvasive or invasive alternatives depending upon the etiology, associated disorders, and preference of the patient.