Relationship between Hypovitaminosis D and Cardiac Abnormalities in Pre Dialysis Chronic Kidney Disease

Abstract

Background: The presence of structural and functional changes in the left ventricle (LV) are good predictors of cardiovascular events in patients with chronic kidney disease (CKD) and are associated with decreasing renal function. Studies in CKD patients on hemodialysis evidenced associations of serum 25-OH vitamin D (vit D) with myocardial function and structural changes. However, it is not known whether serum vit D is associated with Doppler echocardiogram (ECHO)-based cardiac changes in patients with CKD managed conservatively. Hypothesis: Hypovitaminosis D is associated with ECHObased cardiac changes in patients with CKD managed conservatively. Methods: This cross-sectional study included patients with CKD managed conservatively at a reference nephrology outpatient clinic. CKD stage was classified according to the KDIGO guidelines. The glomerular filtration rate was estimated by the CKD-EPI equation. Serum vit D was classified as insufficient/deficient when < 30 ng/mL and as normal when ≥ 30 ng/mL. ECHO-based cardiac changes were classified according to the American Society of Echocardiography criteria. Results: Serum vit D was measured in 137 of the 141 study patients, and 112 patients underwent ECHO. The mean age was 58.8 ± 16.0 years. Most patients were female and 80% self-reported being non-blacks. In multivariate analysis, insufficient/deficient serum vit D levels were independent risk factors for changes in ventricular geometry (OR: 3.85; p = 0.041) and reduced LV ejection fraction (OR: 1.06; p = 0.044), when compared to normal vit D serum levels. Conclusion: In patients with CKD managed conservatively, hypovitaminosis D is independently associated with structural and functional changes in the heart.