Background: The association of subclinical vascular disease and early declines in kidney function has not been well studied.
Study design: Prospective cohort study.
Setting & participants: Multi-Ethnic Study of Atherosclerosis (MESA) participants with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m(2) with follow-up of 5 years.
Predictors: Pulse pressure, small (SAE) and large arterial elasticity (LAE), and flow-mediated dilation.
Outcomes: Kidney function decline.
Measurements: SAE and LAE were measured by pulse contour analysis of the radial artery. Kidney function was assessed by eGFR based on serum creatinine (eGFR(SCr)) and cystatin C (eGFR(SCysC)).
Results: For 4,853 adults, higher pulse pressure and lower SAE and LAE had independent and linear associations with faster rates of kidney function decline. Compared with persons with pulse pressure of 40-50 mm Hg, eGFR(SCysC) declines were 0.29 (P = 0.006), 0.56 (P < 0.001), and 0.91 (P < 0.001) mL/min/1.73 m(2)/y faster in persons with pulse pressure of 50-60, 60-70, and >70 mm Hg, respectively. Compared with the highest quartile of SAE (most elastic), eGFR(SCysC) declines were 0.26 (P = 0.009), 0.35 (P = 0.001), and 0.70 (P < 0.001) mL/min/1.73 m(2)/y faster for the second, third, and fourth quartiles, respectively. For LAE, compared with the highest quartile, eGFR(SCysC) declines were 0.28 (P = 0.004), 0.58 (P < 0.001), and 0.83 (P < 0.001) mL/min/1.73 m(2)/y faster for each decreasing quartile of LAE. Findings were similar for eGFR(SCr). In contrast, for 2,997 adults with flow-mediated dilation and kidney function measures, flow-mediated dilation was not associated significantly with kidney function decline. For every 1-standard deviation greater flow-mediated dilation, eGFR(SCysC) and eGFR(SCr) changed by 0.05 (P = 0.3) and 0.06 mL/min/1.73 m(2)/y (P = 0.04), respectively.
Limitations: We had no direct measure of GFR, in common with nearly all large population-based studies.
Conclusions: Higher pulse pressure and lower arterial elasticity, but not flow-mediated dilation, were associated linearly and independently with faster kidney function decline in persons with eGFR ≥60 mL/min/1.73 m(2). Future studies should investigate whether treatments to decrease the stiffness of large and small arteries may slow the rate of kidney function loss.
Copyright © 2011 National Kidney Foundation, Inc. All rights reserved.