Background: Due to loss of hormonal protective effects, postmenopausal women have an increased cardiovascular (CV) risk. Chronic kidney disease (CKD) is a well-established risk factor for CV disease, but little is known whether mild-to-moderate kidney dysfunction is associated with atherosclerosis burden in the postmenopausal asymptomatic women.
Materials and methods: Subclinical atherosclerosis was evaluated in 125 postmenopausal women with no clinical form of atherosclerosis, by carotid and femoral ultrasonography, ankle-brachial index (ABI), and flow-mediated dilation (FMD). Carotid and femoral atherosclerosis were defined as increased intima-media thickness (IMT) and/or the presence of plaques. Endothelial function was assessed by endothelial dependent (flow-mediated dilation at 1 minute [FMD1]) and independent (flow-mediated dilation after nitroglycerin [FMDNTG]) vasodilation. Classical CV risk factors (age, smoking, obesity, diabetes, blood pressure, and lipids) were evaluated. Kidney function was evaluated in terms of estimated glomerular filtration rate (eGFR) calculated by the CKD-EPI formula. Univariate linear regression and multivariate logistic regressions were used to evaluate the independent associations between kidney function and markers of subclinical atherosclerosis.
Results: In the unadjusted linear analysis, eGFR showed a significant negative association with markers of subclinical atherosclerosis: carotid IMT (R2 = 0.305; p < 0.001), femoral IMT (R2 = 0.19, p < 0.001), carotid plaques (R2 = 0.22; p < 0.001), femoral plaques (R2 = 0.09; p = 0.0005), ABI (R2 = 0.05; p = 0.01), FMD1 (R2 = 0.45; p < 0.001), and FMDNTG (R2 = 0.205, p < 0.001). After adjustment for classical CV risk factors the association remained significant.
Conclusions: Mild-to-moderate reduced eGFR is related to subclinical atherosclerosis, independent of traditional CV risk factors. It is important to detect renal function decline, even if it is mild, to improve risk stratification of subclinical atherosclerosis in postmenopausal women.
Keywords: glomerular filtration rate; postmenopausal women; subclinical atherosclerosis.