Association of cystatin C and depression in healthy elders: The health, aging and body composition study

Abstract

Background/Aims: 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 m2, was not associated with depression. Conclusion: Participants with higher cystatin C had an increased likelihood of developing treated depression. Future studies should target this high-risk group. Copyright © 2010 S. Karger AG, Basel.