ED is a common complication of diabetes and people with diabetes are also prone to developing cardiovascular complications.48 The risk of ED is relatively high in patients with known CVD. This was supported by a study of men with known CVD, in which ED was substantially predictive of all-cause mortality and the composite of CVD death, admission for heart failure, MI and stroke.17 Macroangiopathy, microangiopathy and endothelial dysfunction are among the mechanisms by which diabetes causes ED.
The Epimedium plant is a flowering perennial found throughout Asia and parts of the Mediterranean. Horny Goat Weed’s active ingredient is icariin, a falvonol glycoside and reputed to improve cardiovascular function, hormone regulation, modulation of immunological function and antitumor activity (44). Icariin has also been shown to have a PDE5i effect. Animal studies have been carried out showing improvements in penile hemodynamic parameters. There is one report of tachyarrhythmia and hypomania with the use of this herb (45).
Erectile dysfunction is a common occurrence in men with diabetes. The incidence of erectile dysfunction increases progressively with age, from 5% in men age 20 to 75% in men over age 65. The cause of erectile dysfunction in men with diabetes is usually related to a decrease in the blood supply to the penis as well as to injury to the nerves that are responsible for the erection mechanism. A decrease in testosterone production has also been identified as the cause in some men with diabetes.