Vitamin D cuts the risk of death from COVID-19 by 51% and the risk of ICU admission by 72%, a meta-analysis of randomised controlled trials has found. The new study, published in Pharmaceuticals, is titled “Protective Effect of Vitamin D Supplementation on COVID-19-Related Intensive Care Hospitalisation and Mortality: Definitive Evidence from Meta-Analysis and Trial Sequential Analysis”. Here’s the abstract, summarising the study’s method and results.
Background: The COVID-19 pandemic represents one of the world’s most important challenges for global public healthcare. Various studies have found an association between severe vitamin D deficiency and COVID-19-related outcomes. Vitamin D plays a crucial role in immune function and inflammation. Recent data have suggested a protective role of vitamin D in COVID-19-related health outcomes. The purpose of this meta-analysis and trial sequential analysis (TSA) was to better explain the strength of the association between the protective role of vitamin D supplementation and the risk of mortality and admission to intensive care units (ICUs) in patients with COVID-19.
Methods: We searched four databases on September 20th 2022. Two reviewers screened the randomised clinical trials (RCTs) and assessed the risk of bias, independently and in duplicate. The pre-specified outcomes of interest were mortality and ICU admission.
Results: We identified 78 bibliographic citations. After the reviewers’ screening, only five RCTs were found to be suitable for our analysis. We performed meta-analyses and then TSAs. Vitamin D administration results in a decreased risk of death and ICU admission (standardised mean difference (95% CI): 0.49 (0.34–0.72) and 0.28 (0.20–0.39), respectively). The TSA of the protective role of vitamin D and ICU admission showed that, since the pooling of the studies reached a definite sample size, the positive association is conclusive. The TSA of the protective role of vitamin D in mortality risk showed that the z-curve was inside the alpha boundaries, indicating that the positive results need further studies.
Discussion: The results of the meta-analyses and respective TSAs suggest a definitive association between the protective role of vitamin D and ICU hospitalisation.
Despite these highly positive results, the latest official guidelines from NICE still state that vitamin D is not recommended for the prevention of COVID-19. (NICE also doesn’t recommend the use of ivermectin or budesonide.) Yet remdesivir is recommended despite the WHO finding little or no effect. Will NICE now update its guidelines? I wouldn’t count on it.
Dr. John Campbell discusses the new study in a recent video, arguing the evidence on vitamin D is now conclusive and wondering why adequate vitamin D supplementation is not being officially promoted in the U.K. The fact that the MHRA is 86% industry-funded may have something to do with it, he suggests.
Stop Press: ‘Health Nerd’ thinks the study may be flawed. Read his critique here.