Long-term Effects of Finasteride on Invasive Urodynamics and Symptoms in Treatment of Patients with Bladder Outflow Obstruction Due to Benign Prostatic Hyperplasia

Abstract

Purpose We assess the long-term effects of finasteride on bladder outlet obstruction and symptoms in the treatment of patients with benign prostatic hyperplasia. Materials and Methods Of the original 36 patients assigned to treatment with 5 mg. finasteride daily (group 1) or placebo (group 2) for 6 months 27 completed an open extension study of 5 mg. finasteride for 4 more years. The possible relief of bladder outlet obstruction was monitored with repeated pressure-flow studies at baseline, 6 months and 4.5 years. Results The treatment resulted in a further slight decrease in detrusor pressure at maximum flow rate in group 1 and a significant decrease in group 2 during the 4-year period, whereas improvement in maximum flow rate did not achieve statistical significance. Concomitantly, there was a significant improvement in obstructive and irritative symptoms. Conclusions Finasteride decreases bladder outlet obstruction moderately and only occasionally relieves it completely. However, the decrease in obstruction achieved in many patients is sufficient to improve the symptoms significantly. The beneficial effect is long-lasting.