Vitamin D and the hepatitis B vaccine response: a prospective cohort study and a randomized, placebo-controlled oral vitamin D3 and simulated sunlight supplementation trial in healthy adults.

PURPOSE: To determine serum 25(OH)D and 1,25(OH)2D relationship with hepatitis B vaccination (study 1). Then, to investigate the effects on hepatitis B vaccination of achieving vitamin D sufficiency (serum 25(OH)D ≥ 50 nmol/L) by a unique comparison of simulated sunlight and oral vitamin D3 supplementation in wintertime (study 2). METHODS: Study 1 involved 447 adults. In study 2, 3 days after the initial hepatitis B vaccination, 119 men received either placebo, simulated sunlight (1.3 × standard-erythema dose, 3 × /week for 4 weeks and then 1 × /week for 8 weeks) or oral vitamin D3 (1000 IU/day for 4 weeks and 400 IU/day for 8 weeks). We measured hepatitis B vaccination efficacy as percentage of responders with anti-hepatitis B surface antigen immunoglobulin G ≥ 10 mIU/mL. RESULTS: In study 1, vaccine response was poorer in persons with low vitamin D status (25(OH)D ≤ 40 vs 41-71 nmol/L mean difference [95% confidence interval] - 15% [- 26, - 3%]; 1,25(OH)2D ≤ 120 vs ≥ 157 pmol/L - 12% [- 24%, - 1%]). Vaccine response was also poorer in winter than summer (- 18% [- 31%, - 3%]), when serum 25(OH)D and 1,25(OH)2D were at seasonal nadirs, and 81% of persons had serum 25(OH)D < 50 nmol/L. In study 2, vitamin D supplementation strategies were similarly effective in achieving vitamin D sufficiency from the winter vitamin D nadir in almost all (~ 95%); however, the supplementation beginning 3 days after the initial vaccination did not effect the vaccine response (vitamin D vs placebo 4% [- 21%, 14%]). CONCLUSION: Low vitamin D status at initial vaccination was associated with poorer hepatitis B vaccine response (study 1); however, vitamin D supplementation commencing 3 days after vaccination (study 2) did not influence the vaccination response. CLINICAL TRIAL REGISTRY NUMBER: Study 1 NCT02416895; https://clinicaltrials.gov/ct2/show/study/NCT02416895; Study 2 NCT03132103; https://clinicaltrials.gov/ct2/show/NCT03132103

Factors affecting insulin resistance and its relation to Vitamin D status and clinical nutritional parameters in dialysis patients: A single-center Indian study

The aim of this study was to measure insulin resistance (IR) in dialysis patients and its relation to Vitamin D status and nutritional parameters. We included patients on maintenance dialysis, both hemodialysis and peritoneal dialysis (HD and PD). IR was measured by homeostatic model assessment (HOMA)-IR index defined as fasting serum insulin (μU/L) × fasting blood sugar (mmol/L)/22.5. Baseline Vitamin D levels were measured by chemiluminescence immunoassay (CLIA) method. HOMA-IR index correlated with nutritional parameters such as 7-point subjective global assessment (SGA) and anthropometric measures, for example, body fat percentage, lean body weight (LBW), mid-arm circumference (MAC), and mid-arm muscle circumference (MAMC). A total of 55 patients were studied, of them 74.55% were male with mean age of the study population being 37.44 ± 14.96 years. The prevalence values of Vitamin D deficiency 20 ng/ml, i.e., 3.74 ± 4.37 and 1.67 ± 1.47, respectively (P = 0.018). The other measured parameter which had a significant positive correlation with IR was serum uric acid (r = 0.303, 95% CI = 0.021–0.534, and P = 0.025). In nutritional assessment, body mass index, MAC, and MAMC had statistically significant positive correlation with HOMA-IR index (P ≤ 0.001, 0.004, and 0.004, respectively) unlike SGA (P = 0.480). The mode of dialysis did not have a significant effect on IR (HD vs. PD, P = 0.227). The majority of the patients on maintenance dialysis are Vitamin D deficient. Low Vitamin D level, especially <20 ng/ml, muscle mass, and high serum uric acid level are likely to have more IR in dialysis-dependent patients