Development and validation of a clinical risk score to predict the occurrence of critical illness in hospitalized patients with SFTS

Abstract

BackgroundSevere fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with high mortality. Early identification of patients who may advance to critical stages is crucial. This investigation aimed to establish models to predict SFTS before it reaches the critical illness stage. MethodsBetween January 2016 and September 2022, 278 cases have been included in this study. There were 87 demographic and systemic chosen variables. For selecting the predictive variables from the cohort, the LASSO was utilized, and for identifying independent predictors, multivariate logistic regression was performed. Based on these factors, a nomogram was established for critical illness. Concordance index values, decision curve analysis and the area under the curve (AUC) were also examined. ResultsMultivariate logistic regression demonstrated the most important differentiating factors as;> 65 years old (P < 0.001, OR 3.388, 95 % CI 1.767–6.696), elevated serum PT (P = 0.011, OR 6.641, 95 % CI 1.584–31.934), elevated serum TT (P = 0.005, OR 3.384, 95 % CI 1.503–8.491), and elevated serum bicarbonate (P = 0.014, OR 0.242, 95 % CI 0.070–0.707). The C-index of the nomogram was 0.812 (95 % CI: 0.754–0.869), representing good discrimination. The model also showed excellent calibration. The AUC of the nomogram established based on four factors, as mentioned earlier, was 0.806. Furthermore, the model had the excellent net benefit, as revealed by the decision curve analysis. ConclusionAn accurate risk score system built on manifestations noted in patients with SFTS upon admission to hospital, might be advantageous in managing SFTS.