Diabetes
The pathophysiology of ED in men with diabetes mellitus (DM) is complex and multifactorial. Men with DM, even those without significant comorbidities, suffer from a wide range of sexual dysfunction Viagra in Australia online, including decreased desire and sexual satisfaction. Prevalence of ED among diabetic men that has been reported in the literature ranges widely. Unfortunately, many studies either have not differentiated between DM Type 1 and Type 2, or were not done in Type 1 diabetics. The prevalence of ED among men with DM in the MMAS was reported at three times the general population, or 28% versus 9.6%. A more recent study evaluated self-reported ED in males with DM Type 1 and found a prevalence of 20% overall and 47.1% in those 43 years of age or older. Along with objective factors, such as decreased libido, men with DM Type 2 demonstrate organic causes with a decreased nocturnal penile tumescence.
Several cellular and molecular derangements have been described in diabetic men that contribute to the increased risk of ED in this population. Vascular injury is an important cause of ED in this population. At gross anatomical level, men with diabetes have an increased prevalence of cavernosal arterial insufficiency, thus impaired arterial response, on ultrasound. An early study reported impaired endothelial-mediated vasodilation upon exposure to acetylcholine, a parasympathetic agent, in cavernosal tissue of diabetic men with ED. Since this study, endothelial dysfunction in cavernosal tissue of diabetic men has been characterized by abnormalities including, but not limited to, increased apoptosis, oxidative stress, and overactivity of protein kinase C. Thus, the effect of DM on penile vasculature is mechanically similar to its effect on other vascular structures throughout the body. Although advanced glycation end-products have been demonstrated in cavernosal tissue, their significance remains unclear. While a majority of research has focused on diabetic ED as vascular phenomenon, there is at least correlational evidence that autonomic neuropathy plays a role in the development of ED in diabetics. The existence of ED in men with diabetes is also predicted by age and other complications of diabetes, such as retinopathy and depression.
A large national epidemiologic study was able to review a very large database of the diabetic male population through the use of managed care claims. The study used this database to determine the prevalence of diabetes in men with and without ED. The prevalence of diabetes in men with ED was found to be much higher than the general population. Twenty percent of men suffering from ED were also found to have been diagnosed with diabetes; this is in comparison to only 7.5% in men without ED. Given this finding that men with ED are twice as likely to have diabetes as those without ED, the diagnosis of ED may indeed serve as a useable marker for diabetic screening. A similarly large national study in 2005 evaluating men with ED found four specific comorbidities to be significantly prevalent among men carrying the diagnosis of ED. The authors even suggested that ED may be used as an observable marker for all four: hypertension, hyperlipidemia, depression, and diabetes.
Treatment of ED in Diabetics
Although treatment of ED is discussed later in the book, it is prudent to mention here that certain trials in the past decade have been specifically dedicated to the treatment of ED in diabetic males. A retrospective analysis of data from twelve placebo-controlled trials evaluated the efficacy and safety of tadalafil for the treatment of ED in diabetic males. They confirmed that diabetic men have more severe ED than controls at baseline. Interestingly, they also found that baseline erectile function in the diabetic males correlated inversely with baseline HbA(1)c levels. They concluded that although ED was found to be more severe in the diabetic population, response to tadalafil was only slightly lower than controls for the treatment of ED.