title: Elucidation of the Pattern of the Onset of Male Lower Urinary Tract Symptoms Using Cluster Analysis: Efficacy of Tamsulosin in Each Symptom Group.
abstract: OBJECTIVE
  To present a new grouping of male patients with lower urinary tract symptoms (LUTS) based on symptom patterns and clarify whether the therapeutic effect of α1-blocker differs among the groups.
  
  
  METHODS
  We performed secondary analysis of anonymous data from 4815 patients enrolled in a postmarketing surveillance study of tamsulosin in Japan. Data on 7 International Prostate Symptom Score (IPSS) items at the initial visit were used in the cluster analysis. IPSS and quality of life (QOL) scores before and after tamsulosin treatment for 12 weeks were assessed in each cluster. Partial correlation coefficients were also obtained for IPSS and QOL scores based on changes before and after treatment.
  
  
  RESULTS
  Five symptom groups were identified by cluster analysis of IPSS. On their symptom profile, each cluster was labeled as minimal type (cluster 1), multiple severe type (cluster 2), weak stream type (cluster 3), storage type (cluster 4), and voiding type (cluster 5). Prevalence and the mean symptom score were significantly improved in almost all symptoms in all clusters by tamsulosin treatment. Nocturia and weak stream had the strongest effect on QOL in clusters 1, 2, and 4 and clusters 3 and 5, respectively.
  
  
  CONCLUSIONS
  The study clarified that 5 characteristic symptom patterns exist by cluster analysis of IPSS in male patients with LUTS. Tamsulosin improved various symptoms and QOL in each symptom group. The study reports many male patients with LUTS being satisfied with monotherapy using tamsulosin and suggests the usefulness of α1-blockers as a drug of first choice.
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan. Electronic address: kaika@fmu.ac.jp.
authors.forename: Ken
authors.initials: K
authors.lastname: Aikawa
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Kataoka
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Ogawa
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Akaihata
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Michihiro
authors.initials: M
authors.lastname: Yabe
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Junya
authors.initials: J
authors.lastname: Hata
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Koguchi
authors.affiliation: Department of Urology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kojima
authors.affiliation: Medical Affairs, Astellas Pharma Inc., Tokyo, Japan.
authors.forename: Chihaya
authors.initials: C
authors.lastname: Shiragasawa
authors.affiliation: Medical Affairs, Astellas Pharma Inc., Tokyo, Japan.
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Division of Bioengineering and LUTD Research, Nihon University College of Engineering, Koriyama, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Yamaguchi
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists / Q000627:therapeutic use*; D000368:Aged; D016000:Cluster Analysis; D006801:Humans; D059411:Lower Urinary Tract Symptoms / Q000175:diagnosis* / Q000188:drug therapy*; D008297:Male; D011446:Prospective Studies; D013449:Sulfonamides / Q000627:therapeutic use*; D000077409:Tamsulosin; D016896:Treatment Outcome
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D013449:Sulfonamides; D000077409:Tamsulosin