The Effect of Vitamin B12 Levels on Prognosis in COVID-19 Patients

Objectives: It is known that vitamins have some effects such as suppressing viral replication, developing anti-inflammatory responses and that they increase immunity in COVID-19. This study aimed to investigate the correlation between the vitamin B12 (Vit B12) serum levels and the prognosis of the disease in patients with COVID-19. Material and Method: A total of 408 participants were included in the study. Sociodemographic information such as age, educational status, serum vitamin B12 levels, hemogram parameters, and clinical findings of the patients who were admitted for follow-up after the end of COVID-19 infection was evaluated retrospectively. Serum vitamin B12 level between 150-200 pg/mL was assessed as mild deficiency, the value between 100-150 pg/mL as severe deficiency and the value under 100 pg/mL as extremely severe deficiency. Results: Median age of the participants was 44.51 (18-88) years. The median Vit B12 level of the patients was 179.50 (75-641). Of the patients, 248 (60.70%) had Vit B12 deficiency. The rates of pneumonia and hospitalization were higher and fatigue and loss of taste/smell were more in patients with Vit B12 deficiency. NLR and PLR which are the inflammatory markers were higher in patients with Vit B12 deficiency. The rates of pneumonia and hospitalization were the highest in the severe Vit B12 deficiency group among the Vit B12 deficiency groups. Conclusion: The clinical progression was worse in COVID-19 patients with Vit B12 deficiency than those who had no Vit B12 deficiency. Therefore, it has been concluded that Vitamin B12 supplement can have positive effects on COVID-19 patients; however, more comprehensive further studies with longer duration and higher number of patients are needed.