Hypovitaminosis D and severity of COVID19 respiratory infection in a respiratory intensive care unit (RICU) in Apulia southern Italian region

Abstract

Background: The association between severe hypovitaminosis D (<10ng/ml) and the illness course and deaths related to respiratory failure Coronavirus disease 19 (COVID-19) infection has been already described in the literature. The sun exposure is known to be responsible to increase Vit D circulating level.

Aims: To compare the severity of COVID-19 disease and death’s rate with Vit D levels among all patients admitted in a RICU in Bari during the first and second wave of infection before and after sun exposure during summer.

Methods: Retrospective, observational single centre study of a total of 83 patients admitted to the COVID RICU in Bari between 1.03.2020-30.04.2020 and 1.09.2020-15.11.2020. Patients with moderate to severe Vitamin D deficiency (<20ng/dl) (Group 1; n = 30) were compared with those with Vitamin D> = 20ng/dl (Group 2; n = 83)

Results: A Kaplan Meyer survival curve showed that patients in group1 had significantly reduced survival (Log Rank Mantel Cox 6,836; p = 0.009) compared to group 2. Univariate Cox analysis confirmed that Vitamin D values <20 are a risk factor for mortality (HR 6.370); P = 0.022). Multivariate model of COX Vitamin D values <20 increased the predictive capacity with HR of 30.129 (p = 0.008) compared to the HR of 6.370 of the univariate analysis.

Conclusions: In this study, in comparison to previous findings, patients with moderate to severe Vitamin D deficiency (<20ng/dl) have been found at higher risk for severe COVID19 respiratory infection and mortality.