The role of vitamin D in the age of COVID‐19: A systematic review and meta‐analysis
Roya Ghasemian, Amir Shamshirian, Keyvan Heydari, Mohammad Malekan, Reza Alizadeh‐Navaei, Mohammad Ali Ebrahimzadeh, Majid Ebrahimi Warkiani, Hamed Jafarpour, Sajad Razavi Bazaz, Arash Rezaei Shahmirzadi, Mehrdad Khodabandeh, Benyamin Seyfari, Alireza Motamedzadeh, Ehsan Dadgostar, Marzieh Aalinezhad, Meghdad Sedaghat, Nazanin Razzaghi, Bahman Zarandi, Anahita Asadi, Vahid Yaghoubi Naei, Reza Beheshti, Amirhossein Hessami, Soheil Azizi, Alireza Mohseni, Danial Shamshirian
Abstract
BACKGROUND: Evidence recommends that vitamin D might be a crucial supportive agent for the immune system, mainly in cytokine response regulation against COVID-19. Hence, we carried out a systematic review and meta-analysis in order to maximise the use of everything that exists about the role of vitamin D in the COVID-19. METHODS: A systematic search was performed in PubMed, Scopus, Embase and Web of Science up to December 18, 2020. Studies focused on the role of vitamin D in confirmed COVID-19 patients were entered into the systematic review. RESULTS: Twenty-three studies containing 11 901 participants entered into the meta-analysis. The meta-analysis indicated that 41% of COVID-19 patients were suffering from vitamin D deficiency (95% CI, 29%-55%), and in 42% of patients, levels of vitamin D were insufficient (95% CI, 24%-63%). The serum 25-hydroxyvitamin D concentration was 20.3 ng/mL among all COVID-19 patients (95% CI, 12.1-19.8). The odds of getting infected with SARS-CoV-2 are 3.3 times higher among individuals with vitamin D deficiency (95% CI, 2.5-4.3). The chance of developing severe COVID-19 is about five times higher in patients with vitamin D deficiency (OR: 5.1, 95% CI, 2.6-10.3). There is no significant association between vitamin D status and higher mortality rates (OR: 1.6, 95% CI, 0.5-4.4). CONCLUSION: This study found that most of the COVID-19 patients were suffering from vitamin D deficiency/insufficiency. Also, there is about three times higher chance of getting infected with SARS-CoV-2 among vitamin-D-deficient individuals and about five times higher probability of developing the severe disease in vitamin-D-deficient patients. Vitamin D deficiency showed no significant association with mortality rates in this population.