Hepatitis Delta Coinfection Rates and All-Cause Mortality Among Hepatitis B-Infected Veterans in the USA.

Screening for hepatitis D virus (HDV) is recommended for all individuals with hepatitis B virus (HBV) infection. Coinfected individuals experience more severe liver-related outcomes. We determined the HDV testing and coinfection rates and all-cause mortality among those infected with HBV. We used the US Department of Veterans Affairs (VA) healthcare system's national databases to identify individuals with HBV infection. We determined the proportion of individuals referred to gastroenterologists/hepatologists, or infectious diseases providers, and the proportion screened and tested positive for HDV. We calculated the HBV treatment rates, defined as ≥ 3 months of continuous prescription with an approved drug. Finally, we calculated all-cause mortality stratified by HDV coinfection and HBV treatment status. Among 44,951 individuals with at least one positive HBsAg, HBeAg or HBV DNA test, 5964 (13.3%) were screened for HDV (180 [3.0%] tested positive), and 28,291 (62.9%) were referred to gastroenterology/hepatology or infectious diseases. Treatment for HBV was prescribed for 73 (40.5%) of HDV-coinfected and 2425 (41.9%) HDV-uninfected individuals. All-cause mortality rate per 100 person-years was lower among those without HDV coinfection (2.98 for untreated HBV, 2.53 for treated HBV; p < 0.001) compared with those with HDV coinfection (5.14 for untreated HBV, 3.0 for treated HBV; p = 0.02). Kaplan-Meier curves demonstrated a significantly higher mortality among HDV-coinfected individuals who were not treated for HBV (log-rank p < 0.0001). Screening rates for HDV among HBV-infected individuals are suboptimal. While HDV coinfection is associated with higher all-cause mortality, HBV treatment may confer a survival benefit.