シロドシン投与全症例の有害事象と継続率についての検討

Abstract

We retrospectively evaluated patients who received silodosin for lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH/LUTS) in our hospital, to investigate its efficacy, adverse events and continuance rate. From the release of silodosin (July 2006) through October 2008, 256 patients received silodosin for BPH/LUTS in our hospital. Of these 256, we evaluated 195, as 61 were excluded due to conditions such as prostate cancer. We evaluated the International Prostate Symptom Score (IPSS), quality of life (QOL) index, uroflowmetry and postvoid residual urine volume before and after medication. We calculated the continuance rate of the drug by the Kaplan-Meier method. The patients' mean age was 68.1 years and the mean medicated period was 3.1 months. Overall severity at baseline estimated by the criteria for severity of BPH was mild in 0%, moderate in 69%, and severe in 31%. Silodosin significantly improved the IPSS, QOL index, maximum urinary flow rate and postvoid residual urine volume in 90 patients whose data were available for analysis of the efficacy. Improvements were observed both in voiding symptoms and in storage symptoms. However, 45.6% of the overall efficacy was insufficient. Adverse events were observed in 56 of the 195 cases (28.7%). The most common adverse event was abnormal ejaculation (10.8%). The patients who reported adverse events were significantly younger in age and had lower IPSS and QOL index values after treatment than those without adverse events (mean age: 65.4 vs. 69.2 years old; mean IPSS: 7.7 vs. 13.1, mean QOL index: 2.9 vs. 3.6). The continuance rate for the drug was 12.0% at 1 year on the Kaplan-Meier curve. The development of adverse events was involved in the low continuance rate of silodosin. Modification of treatment such as dose reduction is necessary to continue silodosin.