Incidence of erectile dysfunction and characteristics of patients before and after the introduction of sildenafil in the United Kingdom: cross sectional study with comparison patients

Erectile dysfunction, the consistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance, is reported to occur in association with cardiovascular disease, diabetes, hypertension, hypercholesterolaemia, smoking, spinal cord injury, prostate cancer, genitourinary surgery, psychiatric disorders, and the use of many drugs, including alcohol.1 Sildenafil (Viagra), an oral treatment for erectile dysfunction that was licensed in the United Kingdom in September 1998, selectively inhibits cyclic guanosine monophosphate specific phosphodiesterase type 5, thereby enhancing the vasodilating effect of endogenous nitric oxide. Sildenafil is contraindicated in men being treated with organic nitrates and should be used with caution in men with cardiovascular disease.2 Because sildenafil has been promoted extensively, and because no large, population based studies on the incidence of erectile dysfunction had been reported from the United Kingdom, we were interested in the incidence of the disorder and the characteristics of men with …