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

Summary 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.