Hyperglycemia is common in critically ill patients with COVID-19 and may influence outcomes. This retrospective single-center study published in the Diabetology included 338 ICU patients with COVID-19 and hyperglycemia admitted between August 2021 and February 2022 in Vietnam. Nearly 15,000 bedside glucose measurements were analyzed. Patients were categorized as well-controlled or poorly controlled based on a mean glucose target of 140–180 mg/dL. The primary outcome was in-hospital mortality.

Poor glycemic control occurred in 79% of patients. Independent predictors identified by logistic regression included invasive mechanical ventilation, elevated admission glucose, pre-existing diabetes, HbA1c >7.0%, and prolonged corticosteroid exposure. After propensity score matching, mortality was higher in the poorly controlled group compared with the well-controlled group (54.8% vs 35.5%; p=0.047). Multivariable Cox regression analysis confirmed poor glycemic control as an independent predictor of death (adjusted hazard ratio 1.61; 95% CI 1.01–2.55; p=0.045).

Limitations include retrospective single-center design, pandemic-phase context (Delta variant, low vaccination coverage), unmeasured confounders, reliance on mean glucose values, and potential residual confounding despite matching.

Poor glycemic control was frequent and associated with higher mortality in this ICU cohort. Careful glucose monitoring and tailored corticosteroid management are recommended in this setting.