Hepatitis delta in patients hospitalized in Spain (1997-2018)

Background: Hepatitis delta is the most aggressive form of chronic viral hepatitis. We examined the clinical burden, epidemiological features and time trends for hepatitis delta patients hospitalized in Spain during the last two decades. Methods: Retrospective, observational study using the Spanish National Registry of Hospital Discharges. Information was retrieved since 1997 to 2018. Results: From a total of 79 647 783 nationwide hospital admissions recorded during the study period, 5179 included hepatitis delta as diagnosis. The overall hospitalization rate because of hepatitis delta was 6.5/10(5), without significant yearly changes. In-hospital death occurred in 335 (6.6%) patients. Acute hepatitis and cirrhosis were recorded in 46.5 and 33.5% of hepatitis delta hospitalizations, respectively. Acute hepatitis delta predominated until 2007 (55.9%) whereas cirrhosis increased since then (39.4%). Hepatic decompensation events and liver cancer accounted on average for 16 and 8% of hospitalizations, increasing significantly over time. Coinfection with HIV and hepatitis C virus (HCV) were recognized in 24 and 31.2% of hepatitis delta patients, respectively. All hepatitis C, HIV and injection drug use declined significantly since 2008. Conclusion: The rate of hepatitis delta in patients hospitalized in Spain is low and has remained stable over two decades. However, hepatitis delta-related decompensation events and liver cancer are on the rise. The association of hepatitis delta with injection drug use, HIV and HCV has declined among recently hospitalized hepatitis delta patients.