If not properly controlled, both type 1 and type 2 diabetes can cause complications due to high blood sugar levels. Over time, these high levels can cause irreversible nerve damage and narrow your blood vessels. While nerve damage may affect the sensitivity of your penis, blood vessel damage can affect the blood flow to your penis and make it more difficult for you to get an erection.
This form of therapy has a response rate of well over 70%. The sympathetic nervous system normally maintains the penis in a flaccid or non-erect state. All of the vasoactive drugs, when injected into the corpora cavernosae, inhibit or override sympathetic inhibition to encourage relaxation of the smooth muscle trabeculae. The rush of blood engorges the penile corpora cavernosae sinusoidal spaces and creates an erection.
Previous studies reported that there is a strong chance of future cardiac events when ED occurs in younger men compared with older men.11 Another study suggested that there is consistent association across age groups.12 A study of men with diabetes found that ED acts as an indicator of cardiovascular events after adjusting for other illnesses, psychological aspects and the usual cardiovascular risk factors.13 Another large-scale study comprising 25,650 men with pre-existing ED suggested that these men had a 75 % increased risk of peripheral vascular disease.14 Moreover, some studies demonstrated a relationship between ED score and number of diseased coronary arteries and plaque burden in coronary arteries.2,15
Despite physician’s inexperience and patient’s reluctance to disclose sexual dysfunction problems, attempts to estimate the magnitude of this clinical condition have predicted that over 150 million men worldwide experience some degree of erectile dysfunction. Several studies have demonstrated a wide range regarding the prevalence of erectile dysfunction, which is even higher in patients with essential hypertension where the relative risk is approximately two times higher than in normotensive individuals[6-11]. The etiology can be found in the structural and functional abnormalities of the penile arteries induced by high blood pressure. Smooth muscle hypertrophy, stenotic lesions due to atherosclerosis and impaired blood flow are among the prominent structural alterations whereas endothelial dysfunction and the defective nitric oxide-induced vasodilatory mechanism belong to the main functional abnormalities induced by increased blood pressure[12,13]. As a matter of fact, sexual dysfunction is encountered more frequently that it is indeed believed underlining the need for a more proper and concrete assessment.
Erectile dysfunction (ED) is highly prevalent affecting at least 50 % of men with diabetes mellitus (DM). DM may cause ED through a number of pathophysiological pathways. These include neuropathy, endothelial dysfunction, cavernosal smooth muscle structural/functional changes, and hormonal changes. Lifestyle changes, diabetes control, and treatment of hypogonadism are important as the first step in ED management since there is no curative treatment for ED. Phosphodiesterase type 5 inhibitors (PDE5i) are the first-line treatment option. Intracavernous administration of vasoactive drugs is commonly used as a second-line medical treatment when PDE5i have failed. Alprostadil is the most widely used drug in this second-line setting. The combination of papaverine, phentolamine, and alprostadil represents the most efficacious intracavernous pharmacologic treatment option that may save non-responders to alprostadil. Penile prosthesis implantation can be considered in treatment refractory cases, with excellent functional and safety results in the properly informed patients.
Smoking is an independent risk factor for ED. Tobacco smoking causes direct toxicity to endothelial cells, including decreased eNOS activity, increased adhesion expression and impaired regulation of thrombotic factors.6 A meta-analysis of 19 studies by Tengs and Osgood suggested that 40 % of the impotent men studied were current smokers compared with 28 % who had never smoked.49
Abstract | Full Text PDF | PubMed | Scopus (3562) | Google ScholarSee all References By 1996, fueled by the availability of the new oral agent sildenafil, the number of outpatient visits for ED as estimated by the National Ambulatory Medical Care Survey had increased to 1.3 million per year.5x5Feldman, HA, Johannes, CB, Derby, CA et al. Erectile dysfunction and coronary risk factors: prospective results from the Massachusetts Male Aging Study. Prev Med. 2000; 30: 328–338
To date, there are no studies directly comparing the effectiveness of these three agents among diabetic men with ED, so it is impossible to state that one agent is superior to another in terms of effectiveness in diabetic patients. However, there are an number of studies that compare the individual agents to placebo in diabetic men with ED. For example, Boulton et al.41 completed a 12-week double-blind, placebo-controlled randomized clinical trial of the effectiveness of sildenafil in 219 men with ED and type 2 diabetes. They found that sildenafil resulted in a significant improvement in the ability to both achieve and maintain an erection adequate for sexual intercourse in men with type 2 diabetes. In a similar study, Rendell et al.42 randomized 268 diabetic men with ED to receive either sildenafil in a dose-escalation manner or placebo. At the conclusion of the 12-week study, 56% of the patients in the sildenafil arm reported improved erections, compared to 10% in the placebo arm (P < 0.001). Additionally, 61% of patients in the diabetic arm reported at least one successful attempt at sexual intercourse in the final month of the study, compared to 22% in the control arm (P < 0.001). Similar randomized studies have documented the effectiveness of both tadalafil43 and vardenafil44 in the treatment of diabetes-related ED.
Another common reason for failures of oral therapy is the absence of sexual or genital stimulation prior to attempting sexual intercourse. These medicines facilitate an erection by increasing blood flow to the penis, but they do not act as an aphrodisiac or as an initiator of the erection. A man who is not “in the mood” or does not have adequate physical stimulation will not respond with an erection.