Background: Vitamin D (VitD) deficiency has been reported to be associated with respiratory tract infection. In this work we evaluated the concentration of VitD in COVID-19 patients experiencing acute respiratory infections of different levels of severity excluding those who underwent invasive respiratory support.
Methods: The levels of serum VitD and C-reactive protein (CRP) were analyzed in 118 consecutive hospitalized COVID-19 patients (74 male, 44 female), confirmed with rRT-PCR. Of these patients with ventilation support 52 (44.1%) received oxygen via nasal cannula, oxygen mask or an oxygen mask with a reservoir, 48 (40.7%) were on a continuous positive airway pressure device (CPAP) and 18 (15,3%) on non-invasive mechanical ventilation (NIMV).
Results: The median values (range) of VitD and of CRP were 15.1 ng/mL (1.3-73.3) and 14.2 mg/L (5.0-151.2), respectively. A negative correlation from VitD levels and those of CRP (correlation coefficient: 0.259: P=0.005) was observed. VitD levels in O<inf>2</inf> support patients were significantly higher than in both CPAP and NIMV patients. No statistical differences were found for CRP levels (P=0.834) among the three type of oxygen support. Fewer patients with O<inf>2</inf> support had VitD <30 ng/mL and <20 ng/mL than CPAP and NIMV patients. There were no relationships between VitD and the three classes of IgM (P=0.419) and of IgG (P=0.862) SARS-CoV-2 antibodies values. The behavior was the same for CRP.
Conclusions: Our study shows that a significant proportion of COVID-19 patients have a VitD deficiency and that this condition is more frequent in CPAP and in NIMV patients.