Multisystem biomarker trajectories and early risk of clinically adjudicated cardiogenic shock in severe fever with thrombocytopenia syndrome

Severe fever with thrombocytopenia syndrome (SFTS) is associated with substantial mortality, and shock with cardiac involvement is an important contributor to fatal outcomes. However, biomarker correlates, temporal trajectories, and early warning signals of clinically adjudicated cardiogenic shock (CS) in SFTS remain incompletely defined. We retrospectively analyzed 775 laboratory-confirmed SFTS patients admitted to Nanjing Second Hospital from April 2020 through December 2024. Time to first clinically adjudicated CS after admission was analyzed using univariable Cox regression, least absolute shrinkage and selection operator (LASSO), and multivariable Cox regression. Dynamic trajectories of 6 key biomarkers over the first 14 days were assessed using locally estimated scatterplot smoothing, and restricted cubic spline models were used to characterize continuous exposure-response relationships. Clinically adjudicated CS occurred in 143 patients (18.5%); among 164 in-hospital deaths, 99 (60.4%) occurred in patients with CS. Elevated interleukin-6, N-terminal pro-B-type natriuretic peptide, urea, fibrin/fibrinogen degradation products, and triglycerides were independently associated with increased CS risk, whereas total cholesterol showed an inverse association. Most CS events clustered within the first week after admission, with approximately 85% occurring by day 7. Biomarker trajectory analyses showed sustained increases in inflammatory, cardiac, renal, and coagulation markers in patients who developed CS, whereas lipid markers showed a time-dependent decline. In SFTS, clinically adjudicated CS clusters early after admission and reflects multisystem dysregulation involving inflammatory, cardiac, renal, coagulation, and lipid pathways. A six-biomarker panel may support early recognition of high-risk patients and help define a clinically relevant surveillance window during the first week of hospitalization, although external validation and more objective cardiac assessment are needed before routine implementation.