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

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.