Comparison of the clinical effect of dutasteride therapy for benign prostatic hyperplasia when initiated at different time points: A multicentre, observational, retrospective chart review study.

Aim: To evaluate the effects of early (≤6 months after starting any medical treatment [baseline] for benign prostatic hyperplasia [BPH]), intermediate (between >6 months and 2 years from baseline) and late (2 years after baseline) initiation of add-on dutasteride therapy on the incidence of acute urinary retention (AUR) and BPH-related surgery in Japanese patients with moderate-to-severe BPH.

Methods: This multicentre, observational, retrospective chart review study used anonymised data from Japanese medical records. Eligible patients (≥50 years) were followed from baseline until first AUR, BPH-related surgery or Year 4.

Results: Overall, 1206 patients were included (early initiation: n = 793; intermediate: n = 233; late: n = 180). Early dutasteride initiation was not superior to late initiation in reducing the risk of first AUR or BPH-related surgery from baseline (hazard ratio [HR] 0.733; 95% confidence interval [CI] 0.468-1.150) but was superior in reducing the risk of first AUR alone (HR 3.449; 95% CI 1.796-6.623). One year after initiation, the cumulative incidence of first AUR rose rapidly in the late vs early and intermediate initiation groups. Incidences of all parameters (first AUR/BPH-related surgery, first AUR alone and BPH-related surgery alone) in patients undergoing BPH-related surgery in low incidence sites (ie clinical sites with ≤ 16% incidence of first AUR or BPH-related surgery) were significantly lower in the early vs late initiation groups.

Conclusion: Early dutasteride initiation reduced the risk of AUR in a Japanese real-world setting. A randomised controlled trial is warranted to evaluate the benefit of early initiation in preventing BPH-related surgery in Japanese patients.