General effect of low-dose tamsulosin (0.2mg) as a first-line treatment for lower urinary tract symptoms associated with benign prostatic hyperplasia: A systematic review and meta-analysis

Purpose: In Asian countries, low-dose tamsulosin (0.2mg) is used widely but this dose has been less popular than 0.4mg tamsulosin or other types of alpha blockers. The aim of this study was to investigate the efficacy and safety of low-dose tamsulosin by systematic review and meta-analysis. Methods: We conducted a meta-analysis of improvements of lower urinary tract symptoms using International Prostate Symptom Score (IPSS), maximal urinary flow rate (Qmax), post-voided residual volume (PVR), and quality of life (QOL). Relevant studies were found using MEDLINE, Embase, and the Cochrane library. Final inclusion was determined by randomized controlled trials (RCT) and performance of IPSS. Results: A total of fourteen studies were included, with a total sample size of 2147 subjects (1044 experimental and 1103 controls). Study durations ranged from 4 to 52 weeks. The mean change of IPSS improvement from baseline for tamsulosin was-7.18 (95% CI:-7.83,-6.54). The mean change of QOL improvement from baseline was-1.34 (95% CI:-1.46,-1.22). The overall Qmax improvement from baseline was 2.32ml/sec (95% CI: 1.95, 2.70). The mean change of PVR improvement from baseline was-11.12ml (95% CI:-17.61,-4.64). Regarding safety, four studies did not report any adverse events while others reported that adverse events were all tolerated. Conclusions: Although this study did not consider placebo effect and has high IPSS baseline scores, this study clarifies that low-dose tamsulosin has generally positive effect and safety in treatment of LUTS and could be a suitable option as an initial treatment, especially for patients with low body mass index, as is typical of Asian people.