BACKGROUND & AIMS: Alcoholic hepatitis is an acute life- and health-threatening disease that may be increasingly frequent. However, accurate and representative data on time trends in its incidence and prognosis are not available. This study aims to provide nationwide population-based estimates of alcoholic hepatitis incidence and mortality in Denmark, 1999-2008. METHODS: We identified, from the Danish National Registry of Patients, all patients with a first-time discharge diagnosis of alcoholic hepatitis from 1999 and through 2008. We also ascertained whether patients had cirrhosis. We computed the annual incidence rates as well as 28-, 84-day, 5-year, and 10-year mortality rates. RESULTS: We found 1951 patients with alcoholic hepatitis, 63% men. During the study decade, the annual incidence rate in the Danish population rose from 37 to 46 per 10(6) for men and from 24 to 34 per 10(6) for women. The steepest increase was observed among middle-aged women. The 28-day mortality rate rose from 12% to 15%, and the 84-day mortality rate rose from 14% to 24%, similarly for men and women. The increase in short-term mortality was attributable to increasing patient age and prevalence of cirrhosis. The 5-year mortality was 56% overall, 47% without cirrhosis, and 69% with cirrhosis. CONCLUSIONS: The incidence of alcoholic hepatitis in Denmark has increased during the recent decade. The patients are older at diagnosis and more have cirrhosis, resulting in worse short-term prognosis. The long-term prognosis is grave, especially for patients with cirrhosis. The increase in incidence mirrors changes in alcohol consumption in Denmark.