Vitamin D to prevent COVID-19 or other acute respiratory infections: phase 3 randomised controlled trial (CORONAVIT)

ABSTRACT

IntroductionVitamin D deficiency associates with susceptibility to COVID-19 and other acute respiratory infections (ARI).ObjectiveTo determine whether a ‘test-and-treat’ approach to vitamin D replacement in the general population reduces incidence of COVID-19 or other ARI.MethodsWe randomly assigned 6200 UK adults to receive an offer of a postal vitamin D test with postal provision of a 6-month supply of higher-dose vitamin D (3200 IU/d, n=1550) or lower-dose vitamin D (800 IU/d, n=1550) to those with 25(OH)D <75 nmol/L vs no offer of vitamin D testing or supplementation (n=3100). The primary outcome was the proportion of participants experiencing at least one test- or doctor-confirmed ARI of any cause at 6 months. Secondary outcomes included incidence of COVID-19.Results2958/3100 adults randomised to intervention accepted the offer of testing, of whom 2690 (90.9%) had 25(OH)D <75 nmol/L and received vitamin D supplements (1356 higher-dose, 1334 lower-dose). 72 adults in the higher-dose offer group, 86 in the lower-dose offer group and 132 in the no offer group experienced at least one ARI of any cause during follow-up (odds ratio [OR] for higher-dose vs. no offer 1.05, 95% CI 0.78–1.40;OR for lower-dose vs. no offer 1.27, 0.96–1.68). COVID-19 was diagnosed in 32 adults in the higher-dose offer group, 48 in the lower-dose offer group and 68 in the no offer group (OR for higher-dose vs. no offer 0.90, 0.59–1.37;OR for lower-dose vs. no offer 1.37, 0.94–1.99).ConclusionsIn adults with a high baseline prevalence of vitamin D insufficiency, a test-and-treat approach to vitamin D replacement did not reduce risk of all-cause ARI or COVID-19.Please refer to page A209 for declarations of interest related to this .