Park JS, Lee SW, Choi HY and Moon HS
Purpose: To investigate the efficacy and adverse effects of escalating the dose of tamsulosin in Korean benign prostate hyperplasia (BPH) patients with lower urinary tract symptoms (LUTS).
Materials & methods: From March, 2010 to February, 2011, we prospectively enrolled 120 BPH patients who complained of LUTS. We evaluated the prostate specific antigen (PSA) levels, transrectal ultrasonograms (TRUS), International Prostate Symptom Scores (IPSS), International Index of Erectile Dysfunction Questionnaire-5 (IIEF-5) responses, uroflowmetry measurements and post-voided residuals (PVR) of these patients. At first, tamsulosin 0.2 mg was prescribed for 8 weeks. After 8 weeks, we prescribed tamsulosin 0.4 mg for a further 8 weeks to those patients who had not responded to tamsulosin 0.2 mg. After another 8 weeks we re-evaluated the variables, and assessed side effects. Patients prescribed tamsulosin 0.4 mg were divided into two groups; those whose total IPSS were reduced by more than 3 were assigned to the responder group (n=31), those whose total IPSS were reduced by less than 3 were assigned to the non-responder group (n=29). We then compared the variables and frequencies of adverse effects in the two groups.
Results: 60 patients completed the study. Mean age, prostate volume and PSA were 67.3±7.9 years, 31.0±7.7 ml and 1.8±2.3 ng/ml, respectively. Baseline prostate volume, maximal urine flow rate and IPSS score were higher in the responder group (p<0.05). There was no significant difference in baseline PVR or IIEF-5 between the two groups. Maximal urine flow rate increased in both groups but PVR did not improve in the non-responder group, and IIEF-5 scores decreased slightly in the non-responder group but not in the responder group. Numbers of adverse effects such as orthostatic hypotension, ejaculatory dysfunction, erectile dysfunction, dizziness and gastrointestinal discomfort were not significantly different in the two group (n=5 vs. 8, p=0.430).
Conclusions: Dose escalation of tamsulosin is effective in improving the urinary symptoms of patients with large prostate volumes and high IPSS scores. The incidence of adverse effects is unaffected by tamsulosin dose escalation.