title: Association of cystatin C and depression in healthy elders: the health, aging and body composition study.
abstract: OBJECTIVE
  Depression is highly prevalent in individuals with advanced kidney disease, but is less well studied in individuals with milder disease. We evaluated the association between kidney function and depression in the Health, Aging and Body Composition (Health ABC) study.
  
  
  METHODS
  The study enrolled 3,075 community-dwelling black and white adults aged 70-79 years. Kidney function was measured by cystatin C and estimated glomerular filtration rate (eGFR). The main outcome was incident treated depression.
  
  
  RESULTS
  52% of participants had low (≤1.0), 33% intermediate (>1-1.25) and 15% high cystatin C (>1.25). Kidney function and depression were not associated at baseline. Of 2,731 nondepressed participants at baseline, 95 developed incident depression during follow-up. In unadjusted Cox proportional hazard models, hazard ratios (HR) for incident depression were 1.89 (95% confidence interval (CI) 1.21-2.97) for the intermediate and 2.17 (CI 1.24-3.79) for the high cystatin C group. Intermediate (HR = 1.84) and high (HR = 2.1) serum cystatin C remained associated with incident depression in adjusted models. Chronic kidney disease, defined by an eGFR <60 ml/min/1.73 m(2), was not associated with depression.
  
  
  CONCLUSIONS
  Participants with higher cystatin C had an increased likelihood of developing treated depression. Future studies should target this high-risk group.
authors.affiliation: Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pa. 15216 , USA. evgueni.minev@gmail.com
authors.forename: Evgueni
authors.initials: E
authors.lastname: Minev
authors.forename: Mark
authors.initials: M
authors.lastname: Unruh
authors.forename: Michael G
authors.initials: MG
authors.lastname: Shlipak
authors.forename: Eleanor
authors.initials: E
authors.lastname: Simsonick
authors.forename: Kristine
authors.initials: K
authors.lastname: Yaffe
authors.forename: Tennille S
authors.initials: TS
authors.lastname: Leak
authors.forename: Anne B
authors.initials: AB
authors.lastname: Newman
authors.forename: Linda F
authors.initials: LF
authors.lastname: Fried
mesh_terms: D000368:Aged; D000375:Aging / Q000097:blood*; D000928:Antidepressive Agents / Q000627:therapeutic use; D015415:Biomarkers; D001823:Body Composition; D002908:Chronic Disease; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood*; D003863:Depression / Q000097:blood* / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology; D003866:Depressive Disorder / Q000097:blood* / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D007674:Kidney Diseases / Q000097:blood* / Q000523:psychology; D008297:Male; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D000928:Antidepressive Agents; D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D003404:Creatinine