[A double-blind trial on the effect of alpha-adrenergic blocker (bunazosin hydrochloride) in the symptomatic treatment of prostatism].

A double-blind placebo-controlled study of bunazosin for the treatment of symptomatic prostatism is reported, incorporating urologic departments of 25 hospitals. Four different doses of bunazosin hydrochloride was administrated orally to 174 patients having benign prostatic hyperplasia and 31 with bladder neck contracture for a period of four weeks; high dose group (45 patients, 3 mg/day for the first week followed by 4.5 mg/day for the next three weeks), middle dose group (45 patients, from 1.5 mg/day for the first week to 3.0 mg/day for the next three), low dose group (39 patient, 0.15 mg/day for the first to 1.5 mg/day for the next three) and a control group (40 patients, 0.125 mg/day for the entire four weeks). Subjective symptoms (urinary frequency, retarded urination, prolonged urination, condition of urinary stream and abdominal pressure at voiding) and objective signs (residual ratio, maximum and mean flow rate, voiding time) were observed and analyzed statistically. No bias in the background features was confirmed between any of the four groups. The subjective improvement rates evaluated by the attending doctors demonstrated a significant dose-dependent efficacy of bunazosin by H-test (p less than 0.01), although the objective improvement rates revealed no significant difference between any of the four groups. The global improvement rate evaluated by the same means demonstrated that the middle dose group was significantly superior to the control group (p less than 0.05 by U-test). According to each subjective symptom evaluated by the criteria of the drug efficacy, a dose-dependent significant (p less than 0.01) was noticed between the four groups in the improvement of the voiding condition. Although there was no significant difference by use of the H-test, the middle dose group had a significant superiority to the control group in the improvement rate of retarded voiding by use of the U-test (p less than 0.05). Only in the symptomatic cases of prolonged voiding, were dose-dependent significant differences observed between all four groups by use of the H-test (p less than 0.05). On the other hand, there was no significant difference between the four groups in the subjective or global improvement rates. Judging from the real data and the graded classification of objective signs, the high and middle dose groups were significantly superior to the control in terms of voiding time, and the high and low dose groups were the same as the control for residual urine ratio.(ABSTRACT TRUNCATED AT 400 WORDS)