Prognostic value of SOFA combined with chest CT severity score in patients with critical COVID-19 pneumonia: a retrospective study

Abstract Background: Either sequential organ failure assessment (SOFA) score or chest CT severity score (CT-SS) is often used alone to evaluate the prognosis of patients with critical coronavirus disease 2019 (COVID-19), but each of them has intrinsic deficiency. Herein, we attempted to investigate the predictive value of the combination of SOFA and CT-SS for the prognosis of COVID-19. Materials and Methods: A single-center retrospective study was performed in the Second Affiliated Hospital of Zhejiang University School of Medicine from December 2022 to January 2023. Patients with critical COVID-19 pneumonia were divided into two groups of survival or non-survival of hospitalization. The data including clinical characteristics, CT-SS, SOFA score, laboratory results on admission day were collected and analyzed. In addition, the predictive value of SOFAscore, chest CT-SS, or their combination for in-hospital mortality of COVID-19 pneumonia were compared by receiver operating characteristic (ROC) curve. Results: A total of 424 patients with a mean age of 75.46 years and a major proportion of male (69.10%) were finally enrolled, and the total in-hospital mortality was 43.40% (184/424). In comparison with survival group, significant higher proportions of older age (>75 years), comorbidities including obesity, diabetes, and cerebrovascular disease, more needs of mechanical ventilation and continuous renal replacement therapy (CRRT) were observed in the non-survival group (all P﹤0.05). In addition, non-survival patients had a higher value of creatinine, procalcitonin, C-reactive protein, interleukin-6 , SOFA score , CT-SS (all P﹤0.05) on admission day. Multivariate logistic regression analysis further showed that older age, obesity, diabetes, SOFA score, CT-SS, mechanical ventilation, and lymphocytopenia (all P﹤0.05) were independently related with in-hospital mortality. Moreover, the area under the curve (AUC) of combination of SOFA score and chest CT-SS became significant higher than their respective alone (P＜0.01). Conclusion: A simple combination of SOFA scorewith chest CT-SS on admission elicits a better predictive value for in-hospital mortality of critical COVID-19 patients, which could also serve as a promising indicator for prognosis prediction of other severe lung diseases like severe pneumonia and acute lung injury.