Clinical efficacy of sildenafil citrate and predictors of long-term response.

PURPOSE: We assessed the long-term clinical efficacy of sildenafil citrate (SC) and predictors of satisfactory outcome. MATERIALS AND METHODS: All patients were evaluated with a self-administered questionnaire or by telephone interview before, and 3 months and 2.5 years following the initiation of SC therapy. Current SC use, other therapies and overall level of sexual satisfaction were assessed. Sexual function was measured using an abbreviated version of the International Index of Erectile Function questionnaire. RESULTS: Of the 197 men 97 (49%) were using SC at 2.5 years. Patients with a history of diabetes mellitus or prostate surgery were least likely to be satisfied with SC therapy. Men with vasculogenic etiologies for erectile dysfunction were more likely to be on SC and had better sexual function scores at 2.5 years than men with a history of prostate surgery. The 3-month International Index of Erectile Function questionnaire score was an excellent predictor of sexual satisfaction in men who continued to use SC at 2.5 years. Of the 100 men who discontinued treatment with SC 56% chose not to pursue any other treatment. CONCLUSIONS: SC remains a highly effective and durable oral agent for erectile dysfunction. Improved sexual function and sexual satisfaction were well maintained 2.5 years following the initiation of SC therapy, especially in patients with vasculogenic or psychogenic etiologies of erectile dysfunction. Patients who discontinued SC reported significantly decreased sexual function than their counterparts but under used alternative therapies to improve erectile dysfunction.