title: Establishing normal reference ranges for prostate volume change with age in the population-based Krimpen-study: prediction of future prostate volume in individual men.
abstract: BACKGROUND
  We aim to establish the normal pattern of prostate volume change with age to provide a baseline from which accelerated prostate growth might be identified in patients with lower urinary tract symptoms/benign prostatic hyperplasia (LUTS/BPH).
  
  
  METHODS
  In a community-based study, prostate volume was determined at baseline and after 2.1 and 4.2 years in men without prostate cancer. A bivariate multilevel growth curve model was used to estimate the pattern of change of prostate volume with age.
  
  
  RESULTS
  The average percentage increase of total prostate volume and transition zone volume per year of follow-up was 2.2% and 3.5%, respectively. The final model showed that prostate volume was related to age only. The future prostate volume of an individual can be predicted based on his age and known history of prostate volume. The model was also used to calculate time needed for the prostate volume to increase with a certain percentage, for men with different baseline prostate volume values at different ages.
  
  
  CONCLUSIONS
  This method establishes normal prostate volume values by age using prostate volume history in men without prostate cancer. The model provides baseline data from which disease progression might be detected.
authors.affiliation: Department of Urology, University Medical Center Utrecht, Utrecht, The Netherlands. j.l.h.r.bosch@umcutrecht.nl
authors.forename: J L H R
authors.initials: JL
authors.lastname: Bosch
authors.forename: K
authors.initials: K
authors.lastname: Tilling
authors.forename: A M
authors.initials: AM
authors.lastname: Bohnen
authors.forename: C H
authors.initials: CH
authors.lastname: Bangma
authors.forename: J L
authors.initials: JL
authors.lastname: Donovan
mesh_terms: D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009929:Organ Size; D011467:Prostate / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D012016:Reference Values; D014463:Ultrasonography