Long-term effect of sildenafil citrate on erectile dysfunction after radical prostatectomy: 3-year follow-up.

OBJECTIVES To evaluate the long-term effect and safety of sildenafil citrate for the treatment of erectile dysfunction after radical prostatectomy (RP). METHODS The study consisted of 91 patients with erectile dysfunction from our institution who received oral sildenafil citrate after RP. We surveyed these patients using a self-administered questionnaire during the first year of sildenafil citrate use to determine treatment satisfaction, patient compliance, and safety. Those who had responded positively to the drug were surveyed again 3 years later (n = 48). Sildenafil citrate was prescribed at a dose of 50 mg and increased to 100 mg if needed. Data were collected from a self-administered questionnaire using the abridged five-item version of the International Index of Erectile Function questionnaire, referred to as the Sexual Health Inventory of Men, and the Erectile Dysfunction Inventory of Treatment Satisfaction. The patients were stratified according to the type of nerve-sparing (NS) RP procedure they underwent: bilateral NS, unilateral NS, and non-NS. RESULTS At 3 years, 31 (71%) of the 43 patients who had returned the second surveys were still responding to sildenafil. Of these 31 respondents, 10 (31%) had augmented their dose from 50 to 100 mg. The dropout rate was 27%; 6 of 12 had discontinued because of the return of natural erections, 5 because of a loss of efficacy, and 1 because his spouse had died. No differences were found in the 1-year and 3-year five-item International Index of Erectile Function (Sexual Health Inventory of Men) and Erectile Dysfunction Inventory of Treatment Satisfaction scores between the NS groups. The most common side effects at 3 years were headache (12%), flushing (10%), and blue or blurred vision (2%). No patient discontinued the drug at 3 years because of side effects. CONCLUSIONS The results of this study indicate that the vast majority of patients with erectile dysfunction after RP who initially respond to sildenafil continue to do so at 3 years and are satisfied and compliant with the treatment regimen.