Epidemiological characteristics in Shanghai and a prognostic nomogram for 90 day adverse outcomes in acute hepatitis...

Hepatitis E virus (HEV) represents a leading cause of acute viral hepatitis in China, yet large-scale studies characterizing its dynamic epidemiology and enabling early prediction of adverse outcomes remain scarce.

We performed a retrospective cohort study comprising 816 patients hospitalized with acute HEV infection (2019-2024). Predictors were identified through multivariable logistic regression, with Firth's penalized likelihood method applied to address potential small-sample bias, and bootstrap resampling (BCa 95% CI) used to validate estimate robustness. A prognostic nomogram was developed and externally validated in a prospective multicenter cohort, with performance evaluated using AUC, calibration curves, and decision curve analysis.

Among 816 patients (69.6% male, median age 60 years), HEV infection exhibited a winter-spring seasonal pattern in Shanghai, China. The overall 90 day adverse outcome rate was 4.5% in the general population and 18.1% in cirrhotic patients (aOR = 4.37, 95% CI: 1.69-11.33; p = 0.002). No 90 day adverse outcomes occurred in pregnant patients or those with HIV/AIDS. Chronic liver disease (CLD) (OR = 2.65, 1.27-5.70; Firth p = 0.008), MELD score (OR = 1.25, 1.18-1.32; Firth p < 0.001), and neutrophil-to-lymphocyte ratio (NLR) (OR = 1.18, 1.09-1.27; Firth p < 0.001) were independently associated with 90 day adverse outcomes. The CLD-MELD-NLR nomogram achieved high accuracy in the general population (AUC = 0.94, 95% CI: 0.89-0.98), and the MELD-NLR nomogram also performed outstandingly in the CLD subgroup (AUC = 0.90, 95% CI: 0.84-0.96). Both models demonstrated good calibration and clinical utility.

The distinct seasonality and disease burden of HEV in Shanghai highlight the need for targeted local public health measures. The robustly validated CLD-MELD-NLR and MELD-NLR nomograms provide practical tools for early risk stratification and personalized management across diverse clinical settings.