title: Clinical Correlates and Reference Intervals for Cystatin C in a Han Population from Southeast China.
abstract: BACKGROUND
  Cystatin C (CysC) is an endogenous filtration marker for estimation of kidney function. This study aimed to define the reference interval (RI) for serum CysC in a southeast Chinese adult population and to explore the variables that affect serum CysC levels.
  
  
  METHODS
  532 reference individuals (259 male, 273 female, aged 18 - 79 years) were recruited from Guangzhou, China. Multiple regression analysis (MRA) was used to investigate the association between serum CysC levels and clinical factors including age, gender, body mass index, lifestyle, and biochemistry parameters. Reference values were defined using a parametric method according to Clinical and Laboratory Standards Institute guideline (C28A3).
  
  
  RESULTS
  The mean serum CysC levels were significantly lower in females than in males (p < 0.001). Serum CysC levels increased with age (~0.047 mg/L increase per decade). MRA demonstrated that serum CysC levels correlated significantly with serum creatinine (Cr), high density lipoprotein (HDL-C), alkaline phosphatase (ALP), albumin (ALB), and uric acid (UA) concentrations, although their relationships were less prominent than those of gender or age. The RIs for serum CysC levels were calculated at 0.73 - 1.17 mg/L for subjects aged 18 - 49 years and at 0.73 - 1.49 mg/L for those aged 50 - 79 years.
  
  
  CONCLUSIONS
  The RIs for serum CysC were established in a southeast Chinese population. In addition to gender and age, serum Cr, HDL-C, ALP, ALB, and UA also influenced serum CysC levels.
authors.forename: Min
authors.initials: M
authors.lastname: He
authors.forename: Pei-Feng
authors.initials: PF
authors.lastname: Ke
authors.forename: Wei-Ye
authors.initials: WY
authors.lastname: Chen
authors.forename: Hai-Biao
authors.initials: HB
authors.lastname: Lin
authors.forename: Yun-Xiu
authors.initials: YX
authors.lastname: Wang
authors.forename: Ze-Min
authors.initials: ZM
authors.lastname: Wan
authors.forename: Xin-Zhong
authors.initials: XZ
authors.lastname: Wu
authors.forename: Jun-Hua
authors.initials: JH
authors.lastname: Zhuang
authors.forename: Xian-Zhang
authors.initials: XZ
authors.lastname: Huang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers; D002681:China; D003404:Creatinine; D055316:Cystatin C / Q000032:analysis*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012044:Regression Analysis; D055815:Young Adult
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003404:Creatinine