Association of Vitamin D levels on the Clinical Outcomes of Patients Hospitalized for COVID-19 in a Tertiary Hospital

Objectives. This study aimed to compare the severity of COVID-19, inflammatory parameters and clinical outcomes among patients with normal and subnormal levels of Vitamin D. Methodology. This is a retrospective cohort study of 135 patients admitted in a tertiary hospital for COVID-19. Patients were grouped according to their Vitamin D level. Primary outcome measure was the composite of all-cause mortality and morbidity. Other outcome measures determined were the comparison among the groups on the severity of COVID-19 infection, changes in inflammatory parameters, length of hospital stay and duration of respiratory support. Results. There was a significant trend of higher ICU admission (p=0.024), mortality (p=0.006) and poor clinical outcome (p=0.009) among the Vitamin D deficient group. No significant difference was found for most of the inflammatory parameters, duration of hospital stay and respiratory support. Overall, patients with deficient, but not insufficient Vitamin D level had 6 times higher odds of composite poor outcome than those with normal Vitamin D (crude OR=5.18, p=0.003; adjusted OR=6.3, p=0.043). Conclusion. The inverse relationship between Vitamin D level and poor composite outcome observed in our study suggests that low Vitamin D may be a risk factor for poor prognosis among patients admitted for COVID-19.