title: Age and sex influence cystatin C in adolescents with and without type 1 diabetes.
abstract: OBJECTIVE
  To compare serum cystatin C levels, a novel biomarker of renal function, in adolescents with and without type 1 diabetes and to determine what factors affect cystatin C levels.
  
  
  METHODS
  Cystatin C was measured in youth 12-19 years of age with (n = 259, diabetes duration 9 ± 3 years, HbA(1c) 8.9 ± 1.6%) and without diabetes (n = 78). Data were compared by diabetes status, and linear regression was used to determine factors affecting cystatin C.
  
  
  RESULTS
  Cystatin C (0.698 ± 0.083 vs. 0.688 ± 0.127 mg/L, P = 0.40) was similar by diabetes status. In multiple linear regression, cystatin C was associated with age and serum creatinine in nondiabetic subjects and sex, age, and serum creatinine in subjects with diabetes (P < 0.05).
  
  
  CONCLUSIONS
  These data suggest sex differences and age-related changes in cystatin C in adolescents with type 1 diabetes. An understanding of these changes is needed to determine the potential role of cystatin C as a marker of renal function in this population.
authors.affiliation: Barbara Davis Center for Childhood Diabetes, University of Colorado Denver, Aurora, Colorado, USA. david.maahs@ucdenver.edu
authors.forename: David M
authors.initials: DM
authors.lastname: Maahs
authors.forename: Nicole
authors.initials: N
authors.lastname: Prentice
authors.forename: Kim
authors.initials: K
authors.lastname: McFann
authors.forename: Janet K
authors.initials: JK
authors.lastname: Snell-Bergeon
authors.forename: Diana
authors.initials: D
authors.lastname: Jalal
authors.forename: Franziska K
authors.initials: FK
authors.lastname: Bishop
authors.forename: Brittany
authors.initials: B
authors.lastname: Aragon
authors.forename: R Paul
authors.initials: RP
authors.lastname: Wadwa
mesh_terms: D000293:Adolescent; D000367:Age Factors; D015415:Biomarkers / Q000097:blood*; D015992:Body Mass Index; D016022:Case-Control Studies; D002648:Child; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000097:blood*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications / Q000503:physiopathology; D005260:Female; D005919:Glomerular Filtration Rate; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D012044:Regression Analysis; D012737:Sex Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D003404:Creatinine; D055316:Cystatin C; D006442:Glycated Hemoglobin