Impact of cholecalciferol treatment on biomarkers of inflammation and myocardial structure in hemodialysis patients without hyperparathyroidism.

INTRODUCTION: Vitamin D (25-hydroxyvitamin D, 25(OH)D) deficiency, hypovitaminosis D, is highly prevalent in chronic kidney disease patients and is potentially involved with complications in the hemodialysis (HD) population. The aim of this study was to evaluate the impact of cholecalciferol supplementation on biomarkers of mineral metabolism, inflammation, and cardiac function in a group of HD patients presenting with hypovitaminosis D and low intact parathyroid hormone (iPTH) levels. MATERIAL AND METHODS: HD patients with iPTH levels of <300 pg/mL, not receiving vitamin D therapy, and presenting with 25(OH)D levels of <30 ng/mL were enrolled in this prospective study. Oral cholecalciferol was prescribed once a week in the first 12 weeks (50,000 IU) and in the last 12 weeks (20,000 IU) of the study. High-sensitivity C-reactive protein, interleukin-6, and serum albumin were used as inflammatory markers. Echocardiograms were performed on a midweek interdialytic day at baseline and after 6 months of cholecalciferol supplementation. RESULTS: In all, 30 patients were included in the final analysis. We observed a significant increase in serum 25(OH)D levels after 3 months (46.2 ± 14.4 ng/mL vs. 18.1 ± 6.6 ng/mL; P < .001) and after 6 months (40.4 ± 10.4 ng/mL vs. 18.1 ± 6.6 ng/mL; P < .001) of cholecalciferol supplementation. There were no significant changes in alkaline phosphatase, iPTH, phosphorus, and serum albumin levels, but there was a slight but significant increase in calcium levels after 6 months of cholecalciferol supplementation (9.4 ± 0.6 mg/dL vs. 9.0 ± 0.6 mg/dL; P = .02). Additionally, we observed a significant reduction in high-sensitivity C-reactive protein levels after 3 months (median: 0.62 [0.05 to 29.6] mg/L vs. 0.32 [0.02 to 3.13] mg/L; P = .02) and after 6 months (median: 0.62 [0.05 to 29.6] mg/L vs. 0.50 [0.02 to 5.66] mg/L; P = .04) of cholecalciferol supplementation, as well as a significant reduction in interleukin-6 levels (median: 6.44 pg/mL vs. 3.83 pg/mL; P = .018) after 6 months of supplementation. Left ventricular mass index was significantly reduced at the end of supplementation (159 ± 55 g/m(2) vs. 175 ± 63 g/m(2); P = .03). CONCLUSIONS: Cholecalciferol supplementation in HD patients was found to be safe and efficient to correct hypovitaminosis D and established little impact on mineral metabolism markers. Additionally, we observed a reduction in important surrogate markers of cardiovascular risk, namely systemic inflammation and left ventricular hypertrophy, suggesting an anti-inflammatory action and possibly an improvement of cardiac dysfunction.

Hypovitaminosis D is associated with systemic inflammation and concentric myocardial geometric pattern in hemodialysis patients with low iPTH levels.

BACKGROUND: Vitamin D [25(OH)D] deficiency is a cardiovascular risk factor in the hemodialysis (HD) population. The aim of this study was to identify hypovitaminosis D in HD patients without signs of hyperparathyroidism and to analyze its association to inflammation and echocardiographic alterations. METHODS: Patients on HD with iPTH <300 pg/ml not receiving vitamin D therapy were recruited. Hypovitaminosis D was defined as 25(OH)D <30 ng/ml. High-sensitivity C-reactive protein, interleukin-6 and serum albumin were used as inflammation markers. Echocardiograms were performed in an interdialytic mid-week day. RESULTS: Sixty-one patients (mean age of 56 ± 15 years, 52% males, 93% Caucasians, 31% diabetic) were included, and 75% presented hypovitaminosis D. Inflammation was more prevalent among those with hypovitaminosis D, and these patients presented higher relative wall thickness (0.48 ± 0.11 vs. 0.42 ± 0.10 mm; p = 0.05) and lower left ventricular diastolic (49.8 ± 6.2 vs. 54.7 ± 5.8 mm; p = 0.013) and systolic (31.9 ± 5.7 vs. 36.8 ± 7.2 mm; p = 0.012) diameters. CONCLUSIONS: Hypovitaminosis D is associated with inflammation and concentric geometric pattern of the left ventricle, even in the absence of high iPTH levels. Vitamin D repletion (aiming to reduce cardiovascular complications) should also be considered in HD patients with normal or low iPTH levels.