title: Metabolic characteristics of the elderly with recurrent calcium oxalate stones.
abstract: OBJECTIVE
  To determine the metabolic characteristics of elderly patients with recurrent calcium oxalate stones.
  
  
  METHODS
  Metabolic abnormalities were investigated in 88 patients with recurrent calcium oxalate stones, including 70 aged <60 years and 18 aged >/=60 years. The frequency of each metabolic abnormality and the value of each urinary constituent were compared among subgroups of age and gender.
  
  
  RESULTS
  Hyperoxaluria was the most common abnormality, present in 56% and 67% of patients aged <60 and >/=60 years, respectively. Hyperuricosuria was significantly more common in older than in younger patients. There were no significant differences in the frequencies of hypercalciuria and hypocitraturia between the age groups. The urinary excretion of oxalate and the ratio of oxalate to creatinine were significantly greater in older than in younger men. The frequency of low urine volume was lower in older than in younger patients and the mean urinary volume was also greater in the older group.
  
  
  CONCLUSIONS
  Hyperuricosuria and hyperoxaluria seem to be essential risk factors for calcium oxalate stone formation in elderly patients. Urinary oxalate excretion is significantly greater in older than in younger stone formers and is more prominent in men.
authors.affiliation: Department of Urology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yagisawa
authors.forename: T
authors.initials: T
authors.lastname: Hayashi
authors.forename: A
authors.initials: A
authors.lastname: Yoshida
authors.forename: H
authors.initials: H
authors.lastname: Okuda
authors.forename: H
authors.initials: H
authors.lastname: Kobayashi
authors.forename: N
authors.initials: N
authors.lastname: Ishikawa
authors.forename: N
authors.initials: N
authors.lastname: Goya
authors.forename: H
authors.initials: H
authors.lastname: Toma
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D002129:Calcium Oxalate / Q000378:metabolism*; D005260:Female; D006801:Humans; D006959:Hyperoxaluria / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D017678:Sex Distribution; D014545:Urinary Calculi / Q000737:chemistry / Q000378:metabolism* / Q000652:urine; D014554:Urination
chemical_list: D002129:Calcium Oxalate