Serum Calcium and Vitamin D levels: Correlation with severity of COVID-19 in hospitalized patients in Royal Hospital, Oman.

Introduction: Studies have revealed hypocalcemia and low vitamin D levels in severe covid-19 that warrant further research.

Objective: Our study investigates the correlation between calcium levels at presentation as a primary endpoint and pre-existing calcium levels as a secondary endpoint to the severity of disease presentation and progression.

Method: Observational cohort study in adults admitted with COVID-19 from March utill September 2020. Multiple clinical scales and laboratory parameters were used to correlate corrected calcium and vitamin D associations with risk factors and outcomes.

Results: Four hundred and forty five patients were included in the study. Hypocalcemic patients had more abnormal laboratory parameters and longer hospitalization duration. Hypocalcemia was in 60-75% of all age groups (p-value 0.053), for which 77.97% were ICU admissions (p-value 0.001) and 67.02% were diabetic (p-value 0.347). There were non-significant correlations between Vitamin D and almost all the parameters except for chronic respiratory diseases, which had a P-value of 0.024.

Conclusion: It can be concluded that hypocalcemia is a significant and reliable marker of disease severity and progression regardless of underlying comorbidities. Vitamin D levels fail to reflect correlation with severity of COVID-19 infections.