Review the Research
Get summaries of key research on vitamin D and COVID-19
Vitamin D Deficiency and Comorbidities as Risk Factors of COVID-19 Infection: A Systematic Review and Meta-Analysis
Take Home Message
Low serum vitamin –D levels were significantly associated with the risk of COVID-19 infection. This relationship was stronger in female than in male COVID-19 patients.
- Significantly lower vitamin D levels were found in COVID-19-positive patients but with variation by study design with the case control being the only design that showed significance
- This relationship was more prominent in female patients than in male patients.
- Male patients showed higher odds of having low vitamin D than female patients
- Comorbidities showed inconsistent, but generally non-significant, associations with COVID-19 infection.
Sixteen studies were included including 5377 COVID-19 positive subjects.
Things to Keep in Mind
- There were discrepancies in the number and sample size of the included studies, leading to some instances of large variance in effect size estimates.
- The authors found significant heterogeneity. They used random-effects models to address heterogeneity, but it may have affected the strength and extrapolation of conclusions.
Low serum vitamin D levels were significantly associated with a high risk of acquiring COVID-19 infection; however, the results varied by study design. This relationship was more prominent in female patients than in male patients. Limited evidence was found regarding relationships between reported comorbidities and COVID-19 infection; therefore, large population-based studies are recommended to establish any association. Vitamin D-deficient individuals should be provided special attention. Vitamin D levels can be monitored and supplementation of vitamin D could be considered in patients to improve their recovery if they contract COVID-19. Vitamin D levels can be monitored and supplementation of vitamin D could be considered in patients to improve their recovery if they contract COVID-19.
- This meta-analysis investigated the association of lower levels of vitamin D and comorbidities with the risk of COVID-19 infection.
- The search was conducted using MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov for articles published until August 20, 2021.
- Observational, cohort and case-control studies that evaluated serum levels of vitamin D in COVID-19-positive and COVID-19-negative patients were included.