A nomogram including admission serum glycated albumin/albumin ratio to predict mortality in patients with severe fever with thrombocytopenia syndrome

Abstract

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a novel tick-borne infectious disease with a high fatality rate. Although several nomograms based on demographic and laboratory data have been reported to predict the prognosis of SFTS in recent studies, baseline serum glycated albumin (GA)/albumin (ALB) ratio included risk model has not been evaluated for the prediction of clinical outcome.

Methods: A total of 214 SFTS patients with integral data admitted to our hospital from May, 2020 to November, 2022 were included in this study. SFTS infection was confirmed by real time fluorescent quantitative PCR (qRT-PCR). The demographic characteristics, clinical and laboratory data were collected with in 24 h of admission and 1 to 2 days before discharge and were analysed retrospectively.

Results: Fiffty-seven patients (26.6%) died. Multivariate logistic regression analysis showed that age, aspartate aminotransferase (AST), blood glucose (GLU), GA/ALB ratio, neutrophil counts (NEU) and lymphocyte percentage (LYM%) were the independent risk factors for mortality. A nomogram by these factors was created using RMS package in the R program. Area under the receiver operating characteristic (ROC) curve (AUC) of this nomogram was 0.88 (95% CI: 0.83, 0.93). This model showed the excellent net benefit, as revealed by the decision curve analysis. GA/ALB ratios were also independent risk factors for poor out clinical come in subgroups of patients with hyperglycemia on admission and with diabetes history. Nomograms were constructed by the independent risk factors in the subgroups. AUCs of the nomograms in the subgroups showed high predictive values for adverse prognosis.

Conclusions: GA/ALB ratios were independent risk factors for mortality in all SFTS patients and subgroups of with hyperglycemia on admission and diabetes history. The nomograms including GA/ALB ratio had high predictive value for adverse clinical outcome.The nomograms provide a basis for clinical decision-making for the treatment of SFTS patients in different clinical settings.

Keywords: Clinical outcome; Glycated albumin/albumin ratio; Nomogram; Prediction; Severe fever with thrombocytopenia syndrome.

Fig. 1

Nomograms for the prediction of mortality in all patients (a), patients with hyperglycemia (> 7 mmol/L) (b), patients with glycemia (≤ 7 mmol/L) (c), and patients with diabetes history (d)

Fig. 2

AUCs of nomograms for the prediction of mortality in all patients (a), patients with hyperglycemia (> 7 mmol/L) (b), patients with glycemia (≤ 7 mmol/L) (c), and patients with diabetes history (d)

Fig. 3

DCA of nomograms for the prediction of mortality in all patients (a), patients with hyperglycemia (> 7 mmol/L) (b), patients with glycemia (≤ 7 mmol/L) (c), and patients with diabetes history (d)