Inflammatory, coagulation, and thrombo-inflammatory biomarkers associated with in-hospital mortality In hospitalised patients with COVID-19

Background: Early risk stratification in hospitalised patients with coronavirus disease 2019 is clinically important, where management relies on routinely available laboratory data. This study evaluated the association of conventional inflammatory, coagulation, hematologic, and oxygenation-related parameters, together with derived thrombo-inflammatory indices, with in-hospital mortality. Methods: This retrospective single-centre cohort study included 78 hospitalised patients with reverse transcription polymerase chain reaction-confirmed coronavirus disease 2019 and documented in-hospital outcomes. Variables included oxygen saturation, leukocyte differential parameters, C-reactive protein, D-dimer, ferritin, lactate dehydrogenase, urea, and creatinine. Derived indices included neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, systemic immune-inflammation index, systemic inflammation response index, D-dimer-to-lymphocyte ratio, C-reactive protein-to-lymphocyte ratio, and an exploratory scaled thrombo-inflammatory hypoxemia-lymphopenia index. Group comparisons, receiver operating characteristic analysis, and age-adjusted logistic regression were performed. Results: Of the 78 patients, 66 survived, and 12 died. Non-survivors had lower oxygen saturation and higher C-reactive protein, D-dimer, ferritin, lactate dehydrogenase, neutrophil percentage and count, and lower lymphocyte percentage and count. Among the derived indices, the neutrophil-to-lymphocyte ratio, systemic immune-inflammation index, systemic inflammation response index, D-dimer-to-lymphocyte ratio, C-reactive protein-to-lymphocyte ratio, and the exploratory scaled thrombo-inflammatory hypoxemia-lymphopenia index were higher in non-survivors. C-reactive protein, D-dimer, neutrophil-to-lymphocyte ratio, D-dimer-to-lymphocyte ratio, C-reactive protein-to-lymphocyte ratio, and the exploratory scaled thrombo-inflammatory hypoxemia-lymphopenia index remained associated with mortality in age-adjusted models. Conclusion: In hospitalised patients with coronavirus disease 2019, in-hospital mortality was associated with higher systemic inflammation, greater coagulation activation, more pronounced lymphopenia, and lower oxygen saturation. Routine laboratory biomarkers and derived thrombo-inflammatory indices may support early mortality-oriented risk stratification.