Gazzaruso C, Solerte SB, Pujia A, Coppola A, Vezzoli M, Salvucci F, Valenti C, Giustina A, Garzaniti A. Erectile dysfunction as a predictor of cardiovascular events and death in diabetic patients with angiographically proven asymptomatic coronary artery disease: a potential protective role for statins and 5-phosphodiesterase inhibitors, J Am Coll Cardiol , 2008, vol. 51 (pg. 2040-2044)https://doi.org/10.1016/j.jacc.2007.10.069
Crossref | PubMed | Scopus (697) | Google ScholarSee all References Subsequent in vitro electrical stimulation of these tissue samples showed decreased neurogenic and endothelium-dependent smooth muscle relaxation in the tissue from the patients with diabetes. These effects persisted even after controlling for smoking and hypertension. Other studies have shown a heightened smooth muscle tone in patients with diabetes mellitus.24x24Christ, GJ, Stone, B, and Melman, A. Age-dependent alterations in the efficacy of phenylephrine-induced contractions in vascular smooth muscle isolated from the corpus cavernosum of impotent men. Can J Physiol Pharmacol. 1991; 69: 909–913
A similar situation develops in the fragile penile circulation. Any disturbance in nitric oxide production lowers the capacity to dilate penile arteries, impairing penile engorgement for erection. Release of nitric oxide is readily sabotaged by many conditions, including elevated levels of cholesterol, high blood pressure, increased triglycerides, smoking, metabolic syndrome and diabetes, and excessive consumption of dietary saturated fat.9 If an artery’s inner wall can’t produce nitric oxide, an abnormal constriction of the arteries to the penis follows, effectively choking off blood flow.
Crossref | PubMed | Scopus (23) | Google ScholarSee all References Vardenafil has been shown to be significantly more effective than placebo in the treatment of ED secondary to diabetes mellitus and after radical retropubic prostatectomy.69x69Goldstein, I, Young, JM, Fischer, J, Bangerter, K, Segerson, T, Taylor, T, and Vardenafil Diabetes Study Group. Vardenafil, a new phosphodiesterase type 5 inhibitor, in the treatment of erectile dysfunction in men with diabetes: a multicenter double-blind placebo-controlled fixed-dose study. Diabetes Care. 2003; 26: 777–783
A considerable number of patients with ED can have psychogenic factors as the only cause, or in combination with organic causes of ED. Depression, low self-esteem and social stresses are among the psychogenic factors that can lead to ED. Depression is an independent risk factor for both ED and IHD; these three disease conditions are interlinked.51 Psychogenic ED can be managed by multiple psychological interventions such as cognitive behavioural therapy, couples counselling and guided sexual stimulation techniques.52
Crossref | PubMed | Google ScholarSee all References In the general population, the estimated relative risk of experiencing a myocardial infarction within 2 hours after sexual intercourse is approximately 2.5 times higher than the baseline infarction risk of that individual, which itself is extremely low8x8Muller, JE, Mittleman, A, Maclure, M, Sherwood, JB, Tofler, GH, and Determinants of Myocardial Infarction Onset Study Investigators. Triggering myocardial infarction by sexual activity: low absolute risk and prevention by regular physical exertion. JAMA. 1996; 275: 1405–1409
Penile arterial supply (top) and venous drainage (middle), longitudinal views. Bottom, Transverse and longitudinal views of venous return. From Lue TF. Physiology of penile erection and pathophysiology of erectile dysfunction and priapism. In: Walsh PC, Retik AB, Vaughan ED Jr, Wein AJ, eds. Campbell's Urology. Vol 2. 7th ed. Philadelphia, Pa: WB Saunders Co; 1998:1157-1179. With permission from Elsevier.
Relaxation of erectile tissue requires nitric oxide from nonadrenergic-noncholinergic neurons and the endothelium.21 Penile tissue from diabetic men with ED demonstrates impaired neurogenic and endothelium-mediated relaxation of smooth muscle,22 increased accumulation of advanced glycation end products (AGEs),23 and upregulation arginase, a competitor with nitric oxide synthase for its substrate L-arginine.24 Normal responses to direct smooth muscle relaxants in most of these studies implies that the impairments are due to decreased synthesis, release, or activity of nitric oxide. The fundamental mechanisms mediating these changes are thought to be the same as for other diabetic complications: increased polyol pathway flux, intracellular accumulation of AGEs, activation of protein kinase C, and increased flux through the hexosamine pathway.25
In many of these cases, a discussion between the physician, the man with erectile dysfunction, and possibly his partner can help to resolve the issues leading to treatment failure. For men who experience severe side effects, can’t take the drugs for other reasons (such as taking medicines such as nitroglycerin), or don’t respond in spite of further education on the correct use of the drugs, there are other treatment options that can help most men remain sexually active.