title: Circadian changes in urine volume and frequency in elderly men.
abstract: OBJECTIVE
  Circadian changes in urinary frequency, diuresis and bladder capacity were evaluated in middle-aged and elderly patients.
  
  
  METHODS
  A total of 2,703 urinations from 50 men (median age 66 years) was recorded with a 24-hour uroflowmetry system.
  
  
  RESULTS
  During a 24-hour period the elderly group showed increased frequency and decreased bladder capacity. No difference was observed in diuresis between the 2 age groups. From midnight to 6 a.m. frequency in the elderly group was significantly greater (p < 0.01) than that in the middle-aged group.
  
  
  CONCLUSIONS
  Increased frequency in the elderly group during these hours was primarily due to an increase in diuresis.
authors.affiliation: Department of Urology, Jichi Medical School, University of Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: K
authors.initials: K
authors.lastname: Tozuka
authors.forename: A
authors.initials: A
authors.lastname: Tokue
authors.forename: A
authors.initials: A
authors.lastname: Kimura
authors.forename: C
authors.initials: C
authors.lastname: Hamada
mesh_terms: D000367:Age Factors; D000368:Aged; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011470:Prostatic Hyperplasia / Q000503:physiopathology*; D011471:Prostatic Neoplasms / Q000503:physiopathology*; D014554:Urination / Q000502:physiology*; D014556:Urine; D014563:Urodynamics / Q000502:physiology*