Case Control Study to Evaluate the Relationship between Vitamin D Deficiency and Severity of COVID-19 Infection and Outcome

Background: Coronavirus disease (COVID-19) is a systemic disorder caused by severe acute respiratory syndrome corona virus (SARS-COV-2). No established curative treatment for this disease is yet invented. Vitamin D deficiency (VDD) significantly facilitates in worsening COVID 19 infections. Till now, there is no definite verification on its impact on COVID-19 infection. Objective: To evaluate the relationship amid vitamin D-deficiency and severity of COVID-19 infection and its outcome. Methods: The present case-control study was conducted at a medical college hospital, Sylhet, Bangladesh. Total 100 cases and 100 controls were enrolled. Patients categorization were formulated on the ground of severity of COVID infection clinically and Vitamin D level at admission. The relationship among these two categories with different variables was analyzed. All data were processed and analyzed by SPSS (statistical package for social science) version 25. Results: In this study the mean age was 58.46 14.50 years in COVID 19 patients (case group) and 41.96 5.66 years in control group. Majority (64%) was male and 36% was female among COVID 19 patients. Leading risk factor (64%) was DM (diabetes mellitus) followed by smoking (24%) and hypertension (16%). Significant vitamin D deficiency was seen in case group (COVID 19) than control group which was 37% and 22% respectively. Further observed, vitamin D insufficiency was also more in case group (39%) than control group (31%). However, sufficient vitamin D levels were more in control group than case group which was 47% and 24% respectively. The average vitamin D level was 24.10 11.30 in case group and 28.55 11.80 in control group which carried significant statistic value (P<0.05). Thus, Vitamin D level was significantly associated with the COVID 19 disease severity evident by 45.1 % deficiency in severe cases compared to 17.2% among the moderate cases. Conclusion: This study shows the serum level of vitamin D was lower in patients with the COVID 19. It is also found that vitamin D status is remarkably related to COVID-19 severity. Vitamin D supplementation may have a vital role in limiting the impact of this pandemic. More clinical studies are demanded to establish the relationship between COVID 19 patients and the serum level of vitamin D.