Outcomes of High-dose Vitamin D on Non-Vertebral Fractures and Falls
The primary outcome was cardiovascular disease; secondary outcomes included nonvertebral fractures.
Middle-age healthy patients receiving monthly high-dose bolus colecalciferol did not have a reduced risk for fracture or falls, according to recent research published in The Lancet Diabetes & Endocrinology.
The Vitamin D Assessment (ViDA; registered with the Australian New Zealand Clinical Trials Registry number: ACTRN12611000402943) trial was conducted by an international team of researchers from the United Kingdom, New Zealand, and the United States between April 2011 and November 2012 at a single Auckland, New Zealand center.
A total of 5110 patients between aged 50 and 84 years (mean age, 65.9 years; 58% men) were randomly assigned to either colecalciferol (n=2558) or placebo (n=2552). Patients had mean baseline 25-hydroxyvitamin D (25[OH]D) blood concentrations of 63 nmol/L, and 30% of patients (n=1534) had 25(OH)D concentrations <50 nmol/L.
In the colecalciferol group, patients had an initial dose of 200,000 IU (5.0 mg) followed by 100,000 IU (2.5 mg) colecalciferol taken monthly with a mean treatment duration of 3.4 years.
The researchers attempted to raise participants' serum concentrations of 25(OH)D to 80 to 100 nmol/L based on data from observational studies that suggested this range was associated with optimal health.
The primary outcome was cardiovascular disease and secondary outcomes included nonvertebral fractures and respiratory infection, while the number of falls was recorded as a safety outcome.
Overall, 2638 patients experienced a fall during the study, with 52% (n=1312) of patients in the vitamin D group reporting a fall compared with 53% (n=1326) of patients in the placebo group. The vitamin D group had a hazard ratio (HR) of 0.99 (95% CI, 0.92-1.07; P =.82) compared with patients in the placebo group.
Regarding fractures, 6% of patients (n=156) in the vitamin D group and 5% of patients (n=136) in the placebo group reported nonvertebral fractures with an adjusted HR of 1.19 (95% CI, 0.94-1.50; P =.15) in the vitamin D group compared with the placebo group. The researchers noted 2% of patients (n=123) died during the study period, but there was a nonsignificant difference in deaths in each group.
“Further study is needed to assess the effects of daily dosing of vitamin D, with or without calcium supplementation, and international trials are ongoing,” the researchers concluded.
- Khaw K-T, Stewart AW, Waayer D, et al. Effect of monthly high-dose vitamin D supplementation on falls and non-vertebral fractures: secondary and post-hoc outcomes from the randomised, double-blind, placebo-controlled ViDA trial. Lancet Diabetes Endocrinol. 2017;5(6):438-447. doi:10.1016/S2213-8587(17)30103-1
- Bischoff-Ferrari HA, Giovannucci E, Willett WC, Dietrich T, Dawson-Hughes B. Estimation of optimal serum concentrations of 25-hydroxyvitamin D for multiple health outcomes. Am J Clin Nutr. 2006;84(1):18-28.