Chronic Hepatitis B Increases Liver-Related Mortality of Patients With Acute Hepatitis E: A Territorywide Cohort Study From 2000 to 2016

Background. The epidemiology of acute hepatitis A and E has been changing over the last 2 decades. The impact of concomitant chronic hepatitis B (CHB) on clinical outcomes remains unclear. We aimed to evaluate the morbidity and mortality of patients with acute hepatitis A or E with and without underlying CHB. Methods. We identified consecutive patients with acute hepatitis A or E based on hepatitis serology from the electronic medical records of the Hospital Authority of Hong Kong from January 2000 to December 2016. Hepatic events, all-cause mortality, and liver-related mortality within 30 days of the diagnosis of acute hepatitis were evaluated. Results. The cohort included 1068 cases of acute hepatitis A and 846 cases of acute hepatitis E. More patients with acute hepatitis E than those with acute hepatitis A had underlying CHB (13.5% vs 8.0%; P < .001). Patients with hepatitis E had more all-cause mortality (3.9% vs 0.6%; P < .001), liver-related mortality (2.0% vs 0.3%; P < .001), and hepatic events (2.8% vs 0.3%; P < .001) within 30 days from diagnosis. In patients with acute hepatitis E, underlying renal failure (adjusted hazard ratio [aHR], 3.90; P < .001) and age >= 50 years (aHR, 3.25; P = .036) were associated with 30-day all-cause mortality, whereas CHB (aH R, 3.34; P = .02) was associated with 30-day liver-related mortality. Conclusions. The mortality is higher in patients with acute hepatitis E than in those with hepatitis A. Coexisting CHB is the independent risk factor for liver-related mortality in patients with acute hepatitis E.