title: Microalbuminuria, but not cystatin C, is associated with carotid atherosclerosis in middle-aged adults.
abstract: BACKGROUND
  Cystatin C, a marker of renal function, has been shown to be an independent predictor of cardiovascular disease (CVD) in older adults, but few data are available in middle-aged adults. Moreover, no study has compared cystatin C and microalbuminuria as risk factors for CVD outcomes in middle-aged adults, and it is not known whether cystatin C is related to an early stage of atherosclerosis.
  
  
  METHODS
  We evaluated the relationships between serum creatinine, estimated glomerular filtration rate (GFR), serum cystatin C (all divided into tertiles), microalbuminuria and carotid atherosclerosis in a population-based random sample of 523 adults aged 35-64 years from the Seychelles (Indian Ocean). GFR was estimated using the modification of diet in renal disease (MDRD) equation. Intima-media thickness (IMT) was assessed by B-mode ultrasound.
  
  
  RESULTS
  The mean age of the study sample was 52 years, and 55% were women. Carotid IMT was higher in participants with microalbuminuria (802 vs 732 microm, P<0.001) and was inversely associated with GFR tertiles (from 728 to 809 microm, P for trend=0.002). IMT was not associated with cystatin C or creatinine (P for trend=0.10 and 0.16, respectively). In multivariate analyses adjusted for cardiovascular risk factors, the association between microalbuminuria and IMT remained (P=0.047), while the association between GFR and IMT disappeared (P for trend=0.33).
  
  
  CONCLUSIONS
  Microalbuminuria, but not cystatin C, is associated with carotid atherosclerosis beyond traditional cardiovascular risk factors among middle-aged adults. Cystatin C does not have a stronger relationship with carotid atherosclerosis in middle-aged adults than creatinine.
authors.affiliation: Cardiovascular Prevention Clinic, University Outpatient Clinic, Institute of Social and Preventive Medicine, Department of Community Medicine and Public Health, University of Lausanne, and Kantonsspital, St-Gallen, Switzerland. Nicolas.Rodondi@hospvd.ch
authors.forename: Nicolas
authors.initials: N
authors.lastname: Rodondi
authors.forename: Patrick
authors.initials: P
authors.lastname: Yerly
authors.forename: Anne
authors.initials: A
authors.lastname: Gabriel
authors.forename: Walter F
authors.initials: WF
authors.lastname: Riesen
authors.forename: Michel
authors.initials: M
authors.lastname: Burnier
authors.forename: Fred
authors.initials: F
authors.lastname: Paccaud
authors.forename: Pascal
authors.initials: P
authors.lastname: Bovet
mesh_terms: D000328:Adult; D000367:Age Factors; D000419:Albuminuria; D002340:Carotid Artery Diseases / Q000097:blood* / Q000503:physiopathology* / Q000652:urine*; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D055316:Cystatin C; D015891:Cystatins / Q000097:blood*; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D006306:Health Surveys; D006801:Humans; D007668:Kidney / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D012307:Risk Factors; D012750:Seychelles; D017539:Tunica Intima / Q000000981:diagnostic imaging / Q000473:pathology; D014463:Ultrasonography
chemical_list: C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D003404:Creatinine