Objective: Kidney function decline in elderly persons may be the result of microvascular atherosclerosis. As a proxy for the renovascular system, we evaluated the association of clinical and subclinical cardiovascular disease (CVD) with kidney function decline.
Methods: This study included 4380 subjects from the Cardiovascular Health Study, a longitudinal, community-based cohort of persons aged >or=65 from 4 U.S. communities. Creatinine and cystatin C were measured at baseline, year 3, and year 7; eligible subjects had at least two measures. Creatinine-based estimated glomerular filtration rate (eGFR(creat)) was calculated using the MDRD equation. Rapid kidney function decline was defined as an annual eGFR loss >3 mL/min/1.73 m(2). Predictors of rapid kidney decline included prevalent and subclinical measures of CVD.
Results: Mean decline in eGFR(creat) was 0.4+/-2.6/year; 714 (16%) had rapid progression. In multivariate models adjusted for demographics, cardiovascular risk factors, and inflammation, prevalent stroke (OR, 95% CI: 1.55, 1.16-2.08) and heart failure (OR, 95% CI: 1.80, 1.40-2.31) were independent predictors of rapid kidney decline. Among persons without clinical CV, the subclinical disease measures ankle-arm index <0.9 (OR, 95% CI: 1.67, 1.25-2.24), common carotid intima-media thickness (>or=1.14 mm) (OR, 95% CI: 1.52, 1.12-2.06) and internal carotid intima-media thickness (>1.82 mm) (OR, 95% CI: 1.50, 1.12-2.02) had independent associations with rapid kidney function decline. Results were similar using cystatin C.
Conclusion: Clinical atherosclerosis and heart failure and subclinical measures of CVD have independent associations with kidney function decline progression in the elderly, suggesting an underlying role of renal atherosclerosis.