BACKGROUND: Hepatitis delta virus (HDV) requires hepatitis B virus (HBV) for its replication. HDV infection leads to the most severe form of viral hepatitis, which is associated with an increased risk of liver-related morbidity and mortality. HDV prevalence and characteristics of patients with HDV infection are not well described. We aim to evaluate the epidemiology and patient characteristics of HDV-infected patients among a comprehensive claims dataset of commercially-insured adults in the United States.
METHODS: Commercially insured adults (≥18 years) with HBV or HDV infection were identified with ≥1 inpatient claim or ≥2 outpatient claims (ICD-9/10-CM diagnosis codes) ≥30 days apart for HBV monoinfection or HDV infection using the All-Payer Claims Database from 1/1/2014 to 12/31/2020 (study period). HDV prevalence was calculated as the proportion of HDV-infected among HBV-infected patients over the study period; a sub-cohort was identified with the earliest HDV diagnosis defined as the index date from 1/1/2015 to 12/31/2019 and with ≥12 months continuous enrolment before and after the index date. Age, gender, race, income, education, and geographic region were described upon the index date. Comorbidities were assessed during the pre-index period. Continuous variables were summarized via mean ± standard deviation, and categorical variables via frequency and proportions.
RESULTS: Among 105,509 adults with HBV, 4,694 (4.4%) had HDV infection. Among 2,871 adults with HDV identified in the sub-cohort, mean age was 47.5 (±12.1) years; 53.0% were males. Among those with available data on race and socioeconomic status, 47.1% were White, 33.6% were Black, and 18.0% were Asian; 65.5% reported high school as their highest education; mean annual household income was $44,756 (± $47,829); 35.9% of HDV-infected patients lived in the northeast and 33.3% in the north central US regions. At baseline,16.9% of patients had compensated cirrhosis, 10.1% had decompensated cirrhosis, 2.8% had liver cancer, and 1.9% had received a liver transplant. Mean Charlson Comorbidity Index score was 1.6 (± 2.2). Hypertension (41.9%), diabetes (39.6%), history of smoking (25.9%), substance abuse (25.9%), and HIV infection (24.9%) were the top five comorbidities.
CONCLUSIONS: HDV infection prevalence was 4.4% among commercially insured HBV-infected adults in the US. Patients with HDV infection have a high comorbidity burden. These findings underscore a need for earlier identification of HDV infection among HBV-infected patients, diagnosis, and treatment, which can mitigate future disease progression.