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.

Achieving high convective volume in hemodiafiltration: Lessons learned after successful implementation in the HDFit trial.

BACKGROUND AND OBJECTIVES: High-volume online hemodiafiltration (OL-HDF) associates with improved outcomes compared to hemodialysis (HD), provided adequate dosing is achieved as estimated from convective volume (CV). Achievement of high CV and its impact on biochemical indicators following a standardized protocol converting HD patients to OL-HDF has not been systematically reported. We assessed the success of implementation of OL-HDF in clinics naïve to the modality. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: We analyzed the results of the implementation of postdilution OL-HDF in patients randomized to the HDF arm of a clinical trial (impact of hemoDiaFIlTration on physical activity and self-reported outcomes: a randomized controlled trial (HDFit) trial [ClinicalTrials.gov:NCT02787161]). The day before randomization of the first patient to OL-HDF at each clinic staff started a 3-day in-person training module on operation of Fresenius 5008 CorDiax machine in HDF mode. Patients were converted from high-flux HD to OL-HDF under oversight of trainers. OL-HDF was performed over a 6-months follow-up with a CV target of 22 L/treatment. We characterized median achieved CV >22 L/treatment record and analyzed the impact of HDF on biochemical variables. RESULTS: Ninety-seven patients (mean age 53 ± 16 years, 29% with diabetes, and 11% had a catheter) from 13 clinics randomized to the OL-HDF arm of the trial were converted from HD to HDF. Median CV > 22 L/treatment was achieved in 99% (94/95) of OL-HDF patients throughout follow-up. Monthly mean CV ranged from 27.1 L to 27.5 L. OL-HDF provided an increased single pool Kt/V at 3-months (0.2 [95% CI: 0.1-0.3]) and 6-months (0.2 [95% CI: 0.1-0.4]) compared to baseline, and reduced phosphate at 3-months (-0.4 mg/dL [95% CI: -0.8 to -0.12]) of follow-up. CONCLUSIONS: High-volume online hemodiafiltration was successfully implemented with 99% of patients achieving protocol defined CV target. Monthly mean CV was consistently >22 L/treatment during follow-up. Kt/V increased, and phosphate decreased with OL-HDF. Findings resulting from a short training period in several dialysis facilities appear to suggest HDF is an easily implementable technique.