Efficacy of tamsulosin 0.4 mg for the treatment in male with the international Prostate Symptom Score ≥ 20 compared with tamsulosin 0.2 mg

Purpose: Tamsulosin 0.2 mg is commonly used as the start dose for Asian benign prostatic hyperplasia (BPH) patients, while the 0.4 mg is recommended for Western countries. Recent studies reported that efficacy and safety of tamsulosin 0.4 mg is superior to that of tamsulosin 0.2 mg. However, there is a lack of evidence about the efficacy of tamsulosin 0.4 mg for a long time follow-up and focused on BPH patients who complained of severe International Prostate Symptom Scores (IPSSs). This study aimed to evaluate the efficacy of tamsulosin 0.4 mg compared with tamsulosin 0.2 mg in Korean BPH patients with severe IPSSs. Materials and methods: We reviewed data from 13,115 men treated with tamsulosin for symptomatic lower urinary tract symptoms (LUTS) between January 2015 and June 2020. A total of 2,280 participants with a baseline total IPSS ≥20 who completed 4, 12, and 24-week follow-up IPSS and uroflowmetry (UFM) assessments without changing their initial tamsulosin dose were included. The participants were divided into two groups: Group 1 treated with tamsulosin 0.4 mg and Group 2 treated with tamsulosin 0.2 mg. The primary objective of the present study was to prove the superiority of tamsulosin 0.4 mg to 0.2 mg for improvement in total IPSS score and also prove it in IPSS subscores and UFM. Results: Total IPSS for Group 1 (n = 984) had a significant decrease at four weeks compared with Group 2 (n = 1,296) (P = 0.027), and the obstructive subscore decreased more at 12 weeks in Group 1 than in Group 2 (P = 0.042). At four weeks, the maximum urinary flow rate (Qmax) significantly improved in Group 1 compared with Group 2 (P < 0.011). However, there were no significant efficacy differences between the groups at 24 weeks. Conclusion: This study demonstrates the potential superiority of tamsulosin 0.4 mg in improving IPSS and UFM parameters in Korean BPH patients with severe IPSS during the short-term follow-up. However, long-term efficacy requires further investigation.