Hepatitis A hospitalisations in the United States and risk factors for inpatient mortality: A nationwide population study, 1998–2020

Abstract Hepatitis A virus infections in the United States have been declining; however, recent widespread outbreaks have brought the disease back into the spotlight. We aim to describe the epidemiology of hepatitis A hospitalisations from 1998 to 2020 in the United States and investigate risk factors for inpatient mortality. We utilised the National Inpatient Sample database and identified hepatitis A‐related hospitalisations using ICD‐9 and ICD‐10 diagnosis codes. Demographic and clinical data including death, coinfections, comorbidities and pregnancy status were extracted. Data were analysed by logistic and Poisson regression. We identified a total of 213,681 hepatitis A‐related hospitalisations between 1998 and 2020, with hospitalisation rates ranging between 22.4 per 1,000,000 and 62.9 per 1,000,000. Between 1998 and 2015, the hospitalisation rate for hepatitis A was decreasing (IRR = 0.98; 95% CI: 0.97–0.98; p < .001); however, between 2015 and 2020, it increased overall (IRR = 1.22; 95% CI: 1.21–1.23; p < .001). The overall inpatient mortality rate was 2.7%. Age ≥55 years (OR = 1.84; 95% CI: 1.41–2.40; p < .001), alcoholic cirrhosis (OR = 2.53; 95% CI: 1.64–3.90; p < .001), ascites (OR = 2.65; 95% CI: 1.86–3.78; p < .001), hepatorenal syndrome (OR = 9.04; 95% CI: 5.93–13.80; p < .001), heart failure (OR = 1.76; 95% CI: 1.29–2.39; p < .001), pulmonary hypertension (OR = 2.02; 95% CI: 1.28–3.19; p = .003) and malignant neoplasm (OR = 1.75; 95% CI: 1.25–2.45; p = .001) were associated with increased odds of mortality. Tobacco use disorder (OR = 0.52; 95% CI: 0.38–0.70; p < .001) was associated with decreased odds of mortality. None of the hepatitis A‐associated hospitalisations involving pregnant women resulted in death. Hepatitis A hospitalisations initially declined but increased rapidly after 2015. Certain risk factors can be used to predict prognosis of hospitalised patients.