Associations between kidney function and subclinical cardiac abnormalities in CKD.

Heart failure is a common consequence of CKD, and it portends high risk for mortality. However, among patients without known heart failure, the associations of different stages of estimated GFR (eGFR) with changes in cardiac structure and function are not well described. Here, we performed a cross-sectional analysis to study these associations among 3487 participants of the Chronic Renal Insufficiency Cohort Study. We estimated GFR using cystatin C. The prevalence of left ventricular hypertrophy (LVH) assessed by echocardiography was 32%, 48%, 57%, and 75% for eGFR categories ≥60, 45-59, 30-44, and <30 ml/min per 1.73 m(2), respectively. In fully adjusted multivariable analyses, subjects with eGFR levels of <30 ml/min per 1.73 m(2) had twofold higher odds of LVH (OR=2.20, 95% CI=1.40-3.40; P<0.001) relative to subjects with eGFR≥60 ml/min per 1.73 m(2). This reduction in kidney function also significantly associated with abnormal LV geometry but not diastolic or systolic dysfunction. An eGFR of 30-44 ml/min per 1.73 m(2) also significantly associated with LVH and abnormal LV geometry compared with eGFR≥60 ml/min per 1.73 m(2). In summary, in this large CKD cohort, reduced kidney function associated with abnormal cardiac structure. We did not detect significant associations between kidney function and systolic or diastolic function after adjusting for potential confounding variables.