Age, gender, and race effects on cystatin C levels in US adolescents

Clin J Am Soc Nephrol. 2008 Nov;3(6):1777-85. doi: 10.2215/CJN.00840208. Epub 2008 Sep 24.


Background and objectives: The objective of this study was to describe the normal range of serum cystatin C and identify factors associated with variability in serum cystatin C contrasting with factors that are known to influence creatinine levels in the general US adolescent population.

Design, setting, participants, & measurements: Serum cystatin C and creatinine were measured in 719 participants aged 12 to 19 yr in the Third National Health and Nutrition Examination Survey, a national cross-sectional survey conducted in 1988 through 1994. We calculated gender- and race/ethnicity-specific cystatin C and creatinine ranges and conducted multivariable linear regression analyses to assess factors that contribute to variability in cystatin C and creatinine levels.

Results: Overall, the mean serum cystatin C level was 0.84 mg/L and was higher in male than female individuals and higher in non-Hispanic white versus non-Hispanic black and Mexican American individuals. The mean serum creatinine was 0.71 mg/dl and was higher in male than in female individuals but lower in non-Hispanic white and Mexican American compared with non-Hispanic black individuals. Unlike creatinine, which increases with age from 12 to 19 yr, cystatin C levels decrease, particularly in female individuals. After adjustment for age, gender, and race/ethnicity, uric acid and blood urea nitrogen were significantly associated with cystatin C levels.

Conclusions: Serum cystatin C is significantly related to gender, age, race/ethnicity, uric acid, and blood urea nitrogen in adolescents.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Age Distribution
  • Age Factors
  • Biomarkers / blood
  • Black or African American* / statistics & numerical data
  • Blood Urea Nitrogen
  • Child
  • Creatinine / blood
  • Cross-Sectional Studies
  • Cystatin C / blood*
  • Female
  • Health Surveys
  • Humans
  • Male
  • Mexican Americans* / statistics & numerical data
  • Reference Values
  • Sex Distribution
  • Sex Factors
  • United States
  • Uric Acid / blood
  • White People* / statistics & numerical data


  • Biomarkers
  • Cystatin C
  • Uric Acid
  • Creatinine