Association between nutritional risk scores and timing of endotracheal intubation in COVID-19-associated acute respiratory distress syndrome: a single-center cohort study in South Korea

Background: The optimal timing of endotracheal intubation in patients with coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome (ARDS) remains uncertain, and delayed intubation is associated with worse outcomes. Nutritional status, known to affect respiratory function and immune response, may help identify patients at risk of rapid deterioration. This study aimed to evaluate whether nutritional risk scores can predict early intubation in COVID-19-associated ARDS.Methods: We retrospectively analyzed 247 patients with COVID-19-associated ARDS admitted to a tertiary hospital intensive care unit. Nutritional status at admission was assessed using the modified Nutrition Risk in the Critically Ill (mNUTRIC) score and the Prognostic Nutritional Index (PNI). Early intubation was defined as occurring within 24 hours of hospital admission. Receiver operating characteristic curves and multivariate logistic regression were used to evaluate predictive performanceResults: Of 247 patients, 193 (78.1%) required mechanical ventilation, and 133 (68.9%) underwent early intubation. The mNUTRIC score showed moderate discriminatory performance (area under the curve [AUC], 0.705), while PNI performed poorly (AUC, 0.401). In a multivariate analysis adjusted for illness severity, only Acute Physiology and Chronic Health Evaluation II (OR, 1.206, P<0.001) and SOFA scores (OR, 1.270, P=0.028) were independent predictors of early intubation. The mNUTRIC score was not independently associated (P>0.05), suggesting its value is derived from component severity.Conclusions: The predictive power of the mNUTRIC score for early intubation in COVID-19 ARDS was primarily driven by its embedded illness severity components. Nevertheless, the score demonstrated practical utility as a single, composite marker for rapid, holistic evaluation of patient risk.