title: Changes in prostate volume in Japanese patients with benign prostatic hyperplasia: association with other urological measures and risk of surgical intervention.
abstract: OBJECTIVE
  To evaluate changes in prostate volume (PV) and its association with selected urological measures and risk of surgical intervention in Japanese men with benign prostatic hyperplasia (BPH).
  
  
  METHODS
  The medical records of all consecutive urologist-diagnosed BPH patients of >or=40 years old who attended any of four urology clinics in Japan during January 2004-June 2006 were reviewed. Both cross-sectional and longitudinal data were captured to analyze baseline correlations among urological measures, to evaluate the longitudinal changes in PV and selected urological measures, and to examine the predictors of surgical intervention.
  
  
  RESULTS
  The follow-up period was 2.8 years. Mean PV and mean prostate-specific antigen (PSA) of 1331 eligible patients were 34.0 mL and 4.0 ng/mL, respectively. Both measures increased directly with age. Baseline PV correlated with residual urine volume (r = 0.18, P < 0.05) and PSA (r = 0.41, P < 0.001). Among 319 patients who had more than one PV measurement, PV increased in 51% of patients, remained the same in 28% and decreased in 21%. Use of alpha-blockers at baseline and during follow up was not associated with PV change. Patients who had a PV >or=30 mL, a severe International Prostate Symptom Score and a PSA level >or=1.5 ng/mL at baseline, were more likely to have surgical intervention during the follow-up period.
  
  
  CONCLUSIONS
  Predictors generated in this study may help to identify a subset of BPH patients at high risk of surgical intervention.
authors.affiliation: Department of Urology, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, Japan. taijit@sapmed.ac.jp
authors.forename: Taiji
authors.initials: T
authors.lastname: Tsukamoto
authors.forename: Naoya
authors.initials: N
authors.lastname: Masumori
authors.forename: Haruo
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Arai
authors.forename: Akira
authors.initials: A
authors.lastname: Komiya
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Ichikawa
authors.forename: Mineo
authors.initials: M
authors.lastname: Takei
authors.forename: Akito
authors.initials: A
authors.lastname: Yamaguchi
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Martin M
authors.initials: MM
authors.lastname: Crane
mesh_terms: D000328:Adult; D000368:Aged; D044466:Asian People / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011467:Prostate / Q000473:pathology*; D011468:Prostatectomy / Q000706:statistics & numerical data*; D011470:Prostatic Hyperplasia / Q000208:ethnology / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D012307:Risk Factors