Clinical Predictors of Mortality in Severe Fever with Thrombocytopenia Syndrome: An Updated Systematic Review and Meta-Analysis

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne disease with a high case fatality rate and no specific treatment. Identifying robust clinical predictors of mortality is crucial for improving patient outcomes. This systematic review and meta-analysis aimed to comprehensively evaluate the association of underlying diseases, hemorrhagic symptoms, neurological signs, and complications with fatal outcomes in SFTS patients. We systematically searched PubMed, Web of Science, CNKI, and Wan Fang databases up to 1 March 2026 for observational studies. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using fixed- or random-effects models. Forty-five studies, encompassing 8078 patients (1729 deaths), were included. Underlying diabetes (OR = 1.77) and hypertension (OR = 2.38) were significant risk factors. Among hemorrhagic symptoms, systemic manifestations (OR = 4.19), melena (OR = 4.26), and petechiae (OR = 3.20) were strong predictors. Neurological symptoms, particularly coma (OR = 55.07), were the most powerful predictors of death. Complications like multiple organ dysfunction syndrome (MODS, OR = 19.77) and disseminated intravascular coagulation (DIC, OR = 12.02) also significantly increased mortality risk. The findings confirm that a range of clinical features, from underlying conditions to severe neurological and organ complications, are strongly associated with SFTS mortality. These predictors can guide clinicians in early risk stratification and intensive monitoring, especially in high-risk patients, to potentially reduce the high case-fatality rate.