Erectile Dysfunction in Diabetic Men: The Neurological Factor Revisited

Abstract

In the literature the importance of the neurological factor in the etiology of erectile dysfunction in patients with diabetes mellitus is subject to debate. We report on the findings of neurophysiological investigations in 27 impotent and 30 potent diabetic patients, as well as 102 impotent nondiabetic patients. Additionally, hormonal and vascular evaluations were done. The neurophysiological evaluations consisted of assessment of somatic as well as autonomic sensory nerves, by measuring the latencies of somatosensory evoked potentials of the posterior tibial and pudendal nerves, and of the bulbocavernosus and urethro-anal reflexes. The results show a higher incidence of more severe peripheral and autonomic sensory neuropathy in impotent diabetic men. Also, a preponderance of abnormal intracavernous pharmacological tests, suggesting vasculogenic impotence, was found in impotent diabetic patients. No important endocrinological differences were found among the 3 groups under investigation. Significant differences occurred for plasma glucose and glycosylated hemoglobin. We conclude that diabetic urogenital sensory neuropathy has a crucial role in the etiology of diabetic impotence. Angiopathy seems to be of secondary importance. The results show that poor diabetes regulation is associated with diabetic impotence.

Sildenafil citrate for the treatment of erectile dysfunction in men with Type II diabetes mellitus

“…Because poorly controlled diabetes is often associated with diabetic neuropathy [21] and peripheral vascular disease [22], both of which can increase the risk of ED, it is encouraging that treatment with sildenafil was able to improve erections in men with Type II diabetes independent of the degree of glycaemic control or the presence of neuropathic and vascular complications. Moreover, the favourable tolerability coupled with a mechanism of action requiring sexual stimulation, are desirable characteristics for a successful treatment for ED.…”

Prognostic Factors for Response to Sildenafil in Patients with Erectile Dysfunction

“…Nevertheless, the efficacy of sildenafil in diabetic patients is higher than that of a placebo [16] suggesting that, for these patients, several factors are involved which affect the response to sildenafil. In our second multivariate analysis, we can see that the variable ‘etiologic diagnosis’ is selected instead of the variable ‘diabetes mellitus’, thus indicating that the neurologic and arterial lesions are determinants of the poor response [17]. …”

Linking erectile dysfunction and coronary artery disease

“…Peripheral and autonomic neuropathy decreased release of acetylchoine by cholinergic nerves, and sparse penile noradrenergic nervous innervation are a few of the proposed neurologic derangements contributing to ED. [44][45][46][47] …”