Predictive risk score model for severe fever with thrombocytopenia syndrome mortality based on qSOFA and SIRS scoring system

Abstract

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a severe systemic virus infectious disease usually having multi-organ dysfunction which resembles sepsis.Methods: A total of 321 patients with laboratory-confirmed SFTS from May 2013 to July 2017 were retrospectively analysed. Demographic and clinical characteristics, calculated quick sequential organ failure assessment (qSOFA) score and systemic inflammatory response syndrome (SIRS) criteria for survivors and nonsurvivors were compared. Independent risk factors associated with in-hospital mortality were obtained using multivariable logistic regression analysis. Risk score models containing different risk factors for mortality in stratified patients were established whose predictive values were evaluated using area under ROC curve (AUC).Results: Of 321 patients, 87 died (27.1%). Age (p<0.001) and percentage numbers of patients with qSOFA≥2 and SIRS≥2 (p<0.0001) were profoundly greater in nonsurvivors than in survivors. Age, qSOFA, SIRS score and aspartate aminotransferase (AST) were independent risk factors for mortality for all patients. And qSOFA score was the only common risk factor in all patients, those of age≥60 years and those enrolled in intensive care unit (ICU). A risk score model containing all these risk factors (Model1) has high predictive value for in-hospital mortality in these three groups with AUCs (95% CI): 0.919 (0.883-0.946), 0.929 (0.862-0.944) and 0.815 (0.710-0.894), respectively. Kaplan-Meier survival analysis showed a strong difference between high-risk and low-risk groups at a cutoff value > 9.22 (log-rank c2 = 126.3, p <0.0001) Conclusions: qSOFA and risk models containing qSOFA have high predictive validity for SFTS in-hospital mortality.