ABSTRACT
Introduction: Vitamin D (VD) plays a role in immune response. Its benefits on respiratory diseases induced by viruses have been previously described and recent data shows that low levels of VD could worsen COVID-19 outcomes Objectives: To establish association between VD blood levels among COVID-19 patients with their clinical outcomes and biochemical inflammatory markers. Methods: Prospective, multicentric, cohort study. COVID-19 patients were recruited consecutively and grouped as ambulatory or hospitalized, being followed until discharge, transfer to other centers, intensive care unit (ICU) admission or death. The variables evaluated were: age, gender, oxygen mask requirement (O2r), mechanical ventilation (MV), pre-existing comorbidities, inflammatory markers, severity of COVID-19 by News Score. VD levels were classified as: suficient: >30 ng/ml (VDS), insuficient: 20-30 ng/ml (VDI), deficient: <20 ng/ml (VDD). Parametric test, linear multivariate, logistic and cox regressions adjusted by confounders (comorbidities, age) plus survival analysis and long rank were performed. Results: 287 patients were recruited;243 (85%) were hospitalized, showing significant differences in VD levels against ambulatory patients (18±10ng/ml - 24,3±13ng/ml respectively p<0,01). Group classification according to VD and characteristics are expressed in Table1. COVID-19 severe forms and VD levels were negatively associated (p:0,009). VDI and VDD had higher risks for moderate (OR:3,2 95CI:1,1-9 p:0,03) and severe (OR:3 95%CI:1,09-8 p:0,03) disease. VD has also shown correlation with baseline markers as ferritin and LDH (p:0,019 -0,03 respectively). O2r risk was increased between VDI (OR:3,4 95%CI:1,2-9 p:0,016) and VDD (OR:2,74 95%CI:1,1- 6,8 p:0,03) noticing a higher risk in presence of comorbidities, multiplying the odds in 3,39 or 3,6 in presence of 1 or more comorbidities respectively. Lower calcium levels correlated with ICU admission (p:0,02), and noticeably presented itself as a risk factor for mortality ( OR: 7,9 95%CI:1,7-36,3 p:0,008). Image: Conclusion: This study shows that among COVID-19 hospitalized patients, vitamin level was significantly lower, besides its association with O2r, severity and baseline inflammatory markers. Calcium also plays a role in the evolution of this disease and further studies are needed to emphasize the importance of adequate levels of VD and supplementation as an effort to improve COVID-19 outcomes.