Physicians' Academy for Cardiovascular Education

Monthly high-dose vitamin D supplementation does not prevent cardiovascular diseases

Effect of Monthly High-Dose Vitamin D Supplementation on Cardiovascular Disease in the Vitamin D Assessment Study A Randomized Clinical Trial

Scragg R, Stewart AW, Waayer D, et al. - JAMA Cardiol 2017; published online ahead of print

Background

Recent meta-analyses show that a low vitamin D status is associated with an increased cardiovascular disease (CVD) risk [1,2]. However, in other studies there was no or non-significant CVD risk benefit from vitamin D supplementation, which might be due to low dosing and poor adherence [3-6].

In this large randomised, double-blind, placebo-controlled ‘Vitamin D Assessment Study’, the association between a monthly high-dose vitamin D supplementation and the incidence of CVD was evaluated compared with placebo in 5108 New Zealand residents for a median of 3.3 years, in which they received an initial dose of 200 000 IU oral vitamin D3 or placebo, followed by monthly 100 000 IU. Calcium and 25 hydroxyvitamin D [25(OH)D], a metabolite of vitamin D, were measured at baseline and in 10% of random participants at 6, 12, 24 and 36 months. Primary outcome was the number of participants with incident CVD and death, including a prespecified subgroup analysis in participants with vitamin D deficiency.

Main results

Conclusion

In a large randomised clinical trial, monthly high-dose vitamin D supplementation was not associated with a lower CVD risk. These findings do not support routine vitamin D supplementation as a preventive measure for CVD in the general population. However, the effects of daily or weekly dosing needs further study.

References

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Find this article online at JAMA Cardiol