Serum Vitamin D levels in pediatric patients and its association with COVID-19 clinical manifestation: A meta-analysis and systematic review

Background: Vitamin D is involved in human immune system homeostasis and thought to be beneficial for COVID-19 patients, including pediatric population. However, there is still a paucity of information on association of serum vitamin D levels and COVID-19 clinical manifestation in pediatric patients. This study evaluated the association between serum vitamin D levels and clinical manifestations of COVID-19 in pediatric patients.

Methods: We searched PubMed and Google Scholar for articles reporting association between vitamin D and COVID-19 clinical manifestations in pediatric patients. We searched for English-written articles only. PRISMA-MOOSE guideline and quality checklist was complied and statistical analysis was performed using RevMan 5.4.

Results: Ten studies with total of 1,225 patients reported were reviewed. Low vitamin D levels was significantly associated with higher incidence of severe COVID-19 with pooled OR was 5.57 (1.59-19.55; p=0.007). Clinical symptoms were compared between low and normal vitamin D levels. Incidence of fever, cough, ageusia, anosmia, headache, and fatigue were not significantly different between group, with pooled RR was 2.13 (0.13-33.73; p=0.59), 1.25 (0.25-6.22; p=0.78), 0.47 (0.05-4.76; p=0.52), 1.25 (0.21-7.41; p=0.81), 0.91 (0.33-2.55; p=0.86), and 1.02 (0.47-2.22; p=0.96), respectively. The mean count of leukocytes and lymphocytes in the two groups were also not significantly different with pooled RR was -0.49 (-1.39-0.41; p=0.28), and -0.73 (-1.65-0.20; p=0.12), respectively.

Conclusion: Low serum vitamin D level (<20 ng/ml) is associated with the severity of COVID-19 in pediatric patients, but do not affect symptoms and laboratory parameters. Vitamin D supplementation might be beneficial for children undergo medical quarantine and isolation.