Vitamin D Deficiency and Outcome of COVID-19 Patients

Abstract

Infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) poses an enormous challenge to health care systems throughout the world. Without causal treatment, identification of modifiable prognostic factors may help to improve outcomes. To explore possible associations of vitamin D (VitD) status with disease severity and survival, we studied 185 patients diagnosed with coronavirus disease 2019 (COVID-19) and treated at our center. VitD status at first presentation was assessed retrospectively using accredited laboratory methods. VitD deficiency was defined as serum total 25-hydroxyvitamin D level < 12 ng/mL (<30 nM). Primary endpoint was severe course of disease (i.e., need for invasive mechanical ventilation and/or death, IMV/D). Within a median observation period of 66 days (range 2-92), 23 patients required IMV. A total of 28 patients had IMV/D, including 16 deaths. Ninety-three (50%) patients required hospitalization (inpatient subgroup). A total of 41 (22%) patients were VitD deficient. When adjusted for age, gender, and comorbidities, VitD deficiency was associated with higher risk of IMV/D and death (HR 6.12, 95% CI 2.79-13.42, p < 0.001 and HR 14.73, 95% CI 4.16-52.19, p < 0.001, respectively). Similar correlations were observed in the inpatient subgroup. Our study demonstrates an association between VitD deficiency and severity/mortality of COVID-19, highlighting the need for interventional studies on VitD supplementation in SARS-CoV-2 infected individuals.

Keywords: COVID-19; SARS-CoV-2; outcome; retrospective; severity; vitamin D.

Figure A1

Cumulative incidence of invasive mechanical ventilation and/or death and probability of survival in patients with VitD < 20 versus ≥ 20 ng/mL. (A) Cumulative incidence of the composite event invasive mechanical ventilation and/or death according to VitD status in the entire cohort. (B) Survival probability according to VitD status in the entire cohort. (C) Cumulative incidence of the composite event invasive mechanical ventilation and/or death according to VitD status in the inpatient subgroup. (D) Survival probability according to VitD status in the inpatient subgroup.

Figure 1

Histograms of the VitD distribution. (A) Entire cohort (n = 185). (B) Inpatient subgroup (n = 93). (C) Outpatient subgroup (n = 92). Abbreviations: Q1 and Q3, first and third quartile, respectively; SD, standard deviation.

Figure 2

Cumulative incidence of invasive mechanical ventilation and/or death and probability of survival according to VitD status (<12 versus ≥12 ng/mL). (A) Cumulative incidence of the composite event invasive mechanical ventilation and/or death according to VitD status in the entire cohort. (B) Survival probability according to VitD status in the entire cohort. (C) Cumulative incidence of the composite event invasive mechanical ventilation and/or death according to VitD status in the inpatient subgroup. (D) Survival probability according to VitD status in the inpatient subgroup. Abbreviations: CI, confidence interval; HR, hazard ratio; VitD, vitamin D.