Association of glycemic variability and mortality in patients with severe COVID-19

Abstract

The COVID-19 pandemic has generated a severe health, economic, and social crisis never seen before. Fatality is higher in older adults comorbid with hypertension, diabetes, cardiovascular disease and cancer.

Objective: Estimate the association between glycemic variability and mortality in patients with severe COVID-19 from a sentinel hospital in Quito-Ecuador, between 2021-2022.

Methodology: The present study was originally conceived as a retrospective observational cohort study. However, after completing the initial analysis and observing the behavior of the surrogate variables, it was considered necessary to complement it with a nested case-control study. In order to investigate associations of the outcome variable, mortality, with other variables and evaluate whether they play the role of confounders or effect modifiers.

Results: high glycemic variability did not show, in this series, a significant risk of mortality (RR 1.21, 95% CI 0.88-1.66; P= 0.260). It was found that those over 50 years of age had an almost 3 times higher risk (RR 3.25, 95% CI 3.25-7.78; P= 0.003) of elevated glycemic variability than the younger ones and the use of dexamethasone reduced the risk of death in this cohort (RR 0.73; 95% CI: 0.55-0.98; P= 0.044). The stratum of those over 50 years of age had a high risk of death (RR 2.12, 1.36-3.32; P < 0.001). The rest of the variables were studied in the nested case-control design to identify their relationship with the main variable.

Conclusions: high glycemic variability did not reach a significant difference with mortality in patients with COVID-19, parity biased by a probable deficit in glycemic records. However, the influence of age over 50 years on mortality and its reduction when administering high potency corticosteroids was evident.

Keywords: variability, glycemia, mortality, diabetes mellitus, COVID-19.