The purpose of this study was to determine the effect of dutasteride on quality of life of men with lower urinary tract symptoms associated with enlarged prostate or benign prostatic hyperplasia (BPH) as measured by symptom problem index (SPI), BPH-specific interference with activities (BSIA), BPH-specific psychological well-being (BPWB) and BPH-specific lifestyle adaptations (BSLA). Data were derived from three randomized, double-blind studies conducted in 4325 men treated with placebo or dutasteride (0.5 mg/day). Primary analyses included changes from baseline in mean SPI, BSIA, BPWB and BSLA scores. Men treated with dutasteride showed significant improvements in SPI, BSIA, BPWB and BSLA scores compared with placebo.