Vitamin-D levels and intensive care unit outcomes of a cohort of critically ill COVID-19 patients.

OBJECTIVES: The pattern of global COVID-19 has caused many to propose a possible link between susceptibility, severity and vitamin-D levels. Vitamin-D has known immune modulatory effects and deficiency has been linked to increased severity of viral infections. METHODS: We evaluated patients admitted with confirmed SARS-COV-2 to our hospital between March-June 2020. Demographics and outcomes were assessed for those admitted to the intensive care unit (ICU) with normal (>50 nmol/L) and low (<50 nmol/L) vitamin-D. RESULTS: There were 646 SARS-COV-2 PCR positive hospitalisations and 165 (25.5%) had plasma vitamin-D levels. Fifty patients were admitted to ICU. There was no difference in vitamin-D levels of those hospitalised (34, IQR 18.5-66 nmol/L) and those admitted to the ICU (31.5, IQR 21-42 nmol/L). Higher proportion of vitamin-D deficiency (<50 nmol/L) noted in the ICU group (82.0 vs. 65.2%). Among the ICU patients, low vitamin D level (<50 nmol/L) was associated with younger age (57 vs. 67 years, p=0.04) and lower cycle threshold (CT) real time polymerase chain reaction values (RT-PCR) (26.96 vs. 33.6, p=0.02) analogous to higher viral loads. However, there were no significant differences in ICU clinical outcomes (invasive and non-invasive mechanical ventilation, acute kidney injury and mechanical ventilation and hospital days) between patients with low and normal vitamin-D levels. CONCLUSIONS: Despite the association of low vitamin-D levels with low CT values, there is no difference in clinical outcomes in this small cohort of critically ill COVID-19 patients. The complex relationship between vitamin-D levels and COVID-19 infection needs further exploration with large scale randomized controlled trials.

Can a quantitative assessment of SARS-CoV-2 PCR predict degree of severity and outcomes in critical care patients with COVID-19?

Real-Time polymerase chain reaction (qPCR) is the gold standard diagnostic method for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Cycle threshold (Ct) is defined as the number of heating and cooling cycles required during the PCR process. Ct-values are inversely proportional to the amount of target nucleic acid in a sample. Our aim, in this retrospective study, was to determine the impact of serial SARS-CoV-2 qPCR Ct-values on: mortality, need for mechanical ventilation (MV) and development of acute kidney injury (AKI) in patients admitted to the intensive care unit (ICU) with COVID-19. Ct values were evaluated during the time points from pre-ICU admission to week 1, week 2 and week 3 during ICU stay; impact on mortality, need for MV and AKI was determined. There was a continuous increment in Ct-values over the ICU stay from 1st week through to 3rd week. Although not significant, lower ICU 1st week Ct-values were associated with Black ethnicity, increased need for MV and mortality. However, patients who had developed AKI at any stage of their illness had significantly lower Ct-values compared to those with normal renal function. When ICU 1st-week Ct-values are subcategorised as <20, 20-30 and >30 the 28-day survival probability was less for patients with Ct-values of <20. This report shows that the impact of Ct-values and outcomes, especially AKI, among patients at different time points prior to and during ICU stay, larger studies are required to confirm out findings.