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Longitudinal urinary creatinine excretion values among preadolescents and adolescents

Michael D Martin1, James S Woods, Brian G Leroux

  • 1Department of Oral Medicine, University of Washington, Seattle, Wash 98115, USA. mickeym@u.washington.edu

Translational Research : the Journal of Laboratory and Clinical Medicine
|December 7, 2007
PubMed

Insights

Longitudinal urinary creatinine excretion increases with age in children aged 9-17. Black children showed higher creatinine excretion levels than white children, with no significant sex differences observed.

Area of Science:

  • Pediatric Nephrology
  • Biochemistry
  • Growth and Development

Background:

  • Limited longitudinal data exist for urinary creatinine excretion in children aged 9-17.
  • Urinary creatinine is a key indicator of renal function and muscle mass.

Purpose of the Study:

  • To provide comprehensive longitudinal urinary creatinine excretion data for developmentally normal children aged 9-17.
  • To analyze age, sex, and race-related differences in creatinine excretion within this cohort.

Main Methods:

  • Analysis of 7-year longitudinal renal measures from 507 children in a dental materials safety trial.
  • Calculation of urinary creatinine means, confidence intervals, and percentiles (10th, 50th, 90th) by age, sex, and race.
  • Statistical analysis to determine trends and significant differences.

Main Results:

  • Urinary creatinine excretion significantly increases with age in both sexes and all racial groups (P<0.0001).
  • No significant differences in creatinine excretion were observed between sexes.
  • Black children exhibited significantly higher urinary creatinine excretion levels compared to white children (P=0.0003).

Conclusions:

  • Urinary creatinine excretion demonstrates a consistent age-dependent increase during childhood (9-17 years).
  • Race is a significant factor, with higher excretion in Black children, while sex is not.
  • These findings establish normative longitudinal data crucial for pediatric renal health assessment.

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