Doxazosin for benign prostatic hyperplasia: An open-label, baseline-controlled study in Korean general practice

Background: Few studies have reported the treatment of benign prostatic hyperplasia (BPH) in Asian patients. We assessed the safety and efficacy of doxazosin, a selective alpha(1)-adrenoceptor antagonist, in the treatment of Korean patients with symptomatic BPH. Methods: Two hundred and ninety-five men, aged 48 years or older with clinical BPH, were enrolled in a 12-week, open-label, baseline-controlled, dose-titration, multicenter study. A 2-week, single-blind, placebo run-in was followed by 10 weeks of doxazosin treatment, initially administered at 1 mg/day, with upward titrations (2, 4, or 8 mg/day) at 2-week intervals. The international prostate symptom score (IPSS) was used to assess efficacy after 4, 6, and 10 weeks of active treatment. Results: The intent-to-treat (ITT) population comprised 249 patients (mean age 63.6 years). Doxazosin significantly reduced the mean total IPSS by 48%; similarly, the obstructive and irritative subscores were reduced from baseline by 51% and 39%, respectively (P < 0.001 for all scores: Wilcoxon rank sum test). In a subset analysis of 170 normotensive and 78 hypertensive patients, significant reductions in mean systolic and diastolic blood pressures relative to baseline were observed only in the hypertensive subset (P < 0.01). Similar results in mean IPSS were observed in older (greater than or equal to65 years, n = 100) and younger (45-64 years, n = 140) patients, as well as between normotensive and hypertensive patients. Thirty-nine patients reported adverse events: The most frequent were dizziness, dyspepsia, asthenia, somnolence, and dry mouth. Conclusions: The efficacy and safety of doxazosin treatment for BPH were confirmed in this Asian population. Significant improvements in total IPSS, as well as obstructive and irritative subscores, were observed.