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

Background Hepatitis delta virus (HD) is the most aggressive form of chronic viral hepatitis. We examined the clinical burden, epidemiological features and time trends for HD 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 HD as diagnosis. The overall hospitalization rate due to HD was 6.5/105, without significant yearly changes. In-hospital death occurred in 335 (6.6%). Acute hepatitis and cirrhosis were recorded in 46.5% and 33.5% of HD hospitalizations, respectively. Acute HD 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 were recognized in 24% and 31.2% of HD patients, respectively. All hepatitis C, HIV and injection drug use declined significantly since 2008. Conclusion The rate of HD in patients hospitalized in Spain is low and has remained stable over two decades. However, HD-related decompensation events and liver cancer are on the rise. The association of HD with injection drug use, HIV and HCV has declined among recently hospitalized HD patients.