Assessment of the impact of sildenafil citrate on lower urinary tract symptoms in men with erectile dysfunction

Introduction. Sildenafil citrate is an effective and well-tolerated oral erectogenic medication. Through phosphodiesterase type 5 (PDE5) inhibition, it induces relaxation in penile smooth muscle, resulting in erection. Due to its mild affinity for other PDE enzymes, it may cause smooth muscle relaxation in a number of other organs. Recent data suggest an association between erectile dysfunction (ED) and lower urinary tract symptoms (LUTS). Anecdotally some patients cite improvement in LUTS while using sildenafil. Aim. This study was conducted to assess the impact of Viagra on LUTS, using the International Prostate Symptom Score (IPSS) questionnaire. Main Outcome Measure. International Index of Erectile Function (IIEF) and IPSS inventories. Results. Men presenting to a sexual dysfunction clinic who were candidates and opted for treatment with sildenafil completed the IIEF and IPSS. Men with the IPSS scores greater than 10 were enrolled and completed the IPSS and IIEF questionnaires at least 3 months after the commencement of sildenafil. Comparisons were made between pre- and posttreatment scores in the IPSS and erectile function (EF) domain of the IIEF. Conclusions. Forty-eight men were enrolled, with a mean age of 62 +/- 11 years. The mean improvement in the EF domain score was 7 points (P = 0.01). The mean improvement in the IPSS score was 4.6 points (P = 0.013) and in quality of life (QOL) score was 1.4 points (P = 0.025). In total, 60% of men improved their IPSS score, and 35% had at least a 4-point improvement in their score. The mean number of uses of sildenafil per week was 2.0 +/- 0.6. No significant correlation was seen between the degree of the IPSS improvement and baseline IPSS, baseline EF domain score, or magnitude of improvement in EF domain score. These data indicate a positive impact of Viagra on men with mild to moderate LUTS. It is presumed, although unproven, that the medication's effect is mediated through bladder neck/prostatic smooth muscle relaxation.