Patient Preference and Adherence (Jul 2016)
Three-year outcome analysis of alpha 1-blocker naftopidil for patients with benign prostatic hyperplasia in a prospective multicenter study in Japan
Abstract
Naoya Masumori,1 Taiji Tsukamoto,1 Akihiko Shibuya,2 Noriomi Miyao,3 Yasuharu Kunishima,4 Akihiko Iwasawa5 1Department of Urology, Sapporo Medical University School of Medicine, Sapporo, 2Kaguraoka Urological Clinic, Asahikawa, 3Division of Urology, Muroran City General Hospital, Muroran, 4Hokkaido Social Work Association Obihiro Hospital, Obihiro, 5Iwasawa Clinic, Sapporo, Japan Purpose: Our aim was to prospectively analyze the 3-year outcomes of naftopidil treatment for patients with benign prostatic hyperplasia (BPH), including those who dropped out during follow-up and had retreatment for BPH after termination of the drug within 3 years.Patients and methods: Naftopidil, 50 mg/d or 75 mg/d, was given to 117 patients having BPH aged 50 years and older who had international prostate symptom scores (IPSS) ≥8. They were prospectively followed for 3 years with periodic evaluation. If naftopidil was terminated, the reason was determined. For patients with termination, an outcome survey was done to evaluate the status of retreatment for BPH at 3 years.Results: Twenty-five patients (21.4%) continued the same medication for 3 years. The total IPSS, quality of life index, BPH problem index, and maximum flow rate were significantly improved during 3 years. Treatment failure defined as symptomatic progression (an increase in the IPSS of ≥4 points compared to the baseline value), development of acute urinary retention, conversion to other α1-blockers, add-on of a 5α-reductase inhibitor, or conversion to surgery was observed in 41 patients (35.0%). In the univariate analysis, age, prostate volume, and serum prostate-specific antigen were predictors of treatment failure. Of the 50 patients who discontinued naftopidil during the follow-up, only 13 (26%) patients reported that they needed retreatment with α1-blockers and/or surgery within 3 years.Conclusion: Long-term efficacy of naftopidil was observed, although older age, increased prostate volume, and elevated prostate-specific antigen at baseline were highly likely to result in treatment failure. Even after termination for various reasons, only a small portion of the patients needed retreatment for BPH within 3 years. Keywords: benign prostatic hyperplasia, alpha 1-blocker, naftopidil, long-term outcome, treatment failure, retreatment
