Hepatitis Delta Virus: Epidemiology & Clinical Comparison
Hepatitis D Virus Infection in a Large Healthcare Organization: Incidence, Prevalence, and Disease Progression
Table of Contents
abstract
Background: Hepatitis D virus (HDV) infection occurs only in individuals with pre-existing chronic hepatitis B virus (HBV) infection and can lead to more severe liver disease.This study aimed to determine teh incidence and prevalence of HDV among individuals with chronic HBV infection within a large healthcare organization and to assess disease progression in HDV-coinfected versus HBV-monoinfected individuals.
Methods: We conducted a retrospective cohort study using electronic health records from Maccabi Healthcare Services (MHS), a large healthcare organization in Israel, from 2010 to 2021. We identified individuals with chronic HBV infection and steadfast HDV status using diagnostic codes and laboratory results. Incidence and prevalence rates were calculated. Disease progression was assessed using a hierarchical variable representing disease severity (non-cirrhotic, compensated cirrhosis, decompensated cirrhosis, liver cancer, liver transplant, death). Kaplan-Meier plots and Cox regression models were used to compare disease progression between HDV-coinfected and HBV-monoinfected cohorts, adjusting for relevant covariates.Results: Among individuals with chronic HBV infection, the prevalence of HDV coinfection was 7.4% (95% CI: 6.8-8.1%). The annual incidence of HDV was 0.4 per 100 person-years. Individuals with HDV coinfection experienced considerably faster disease progression compared to those with HBV monoinfection (Hazard Ratio = 1.78, 95% CI: 1.45-2.18, P < 0.001). This difference was notably pronounced in individuals with baseline compensated cirrhosis. Conclusions: HDV coinfection is a meaningful public health concern among individuals with chronic HBV infection, accelerating disease progression and increasing the risk of severe liver outcomes. Enhanced screening and treatment strategies are crucial for individuals with HBV to identify and manage HDV coinfection, ultimately improving patient outcomes.
introduction
Chronic hepatitis B virus (HBV) infection affects an estimated 296 million people worldwide, posing a considerable global health burden [1]. Hepatitis D virus (HDV) is a defective RNA virus that requires HBV coinfection for replication and transmission. Approximately 5% of individuals with chronic HBV are also infected with HDV [2]. HDV coinfection can lead to a more aggressive course of liver disease, including accelerated progression to cirrhosis, liver failure, and hepatocellular carcinoma (HCC) [3, 4]. Despite the potential for severe outcomes,HDV remains underdiagnosed and undertreated,particularly in regions with intermediate to high HBV prevalence [5].
Early diagnosis and treatment of HDV are critical to prevent disease progression. Currently, the only approved treatment for HDV is pegylated interferon-alpha (PegIFNα), which can achieve sustained virological response in a proportion of patients, but is associated with significant side effects and is not universally effective [6]. New therapeutic strategies, including entry inhibitors and RNA interference therapies, are under development [7].Israel has a moderate prevalence of HBV infection, with varying rates among different populations [8]. Understanding the epidemiology of HDV among individuals with chronic HBV in Israel is essential for informing public health strategies and improving patient care. This study aimed to determine the incidence and prevalence of HDV among individuals with chronic HBV infection within a large healthcare organization in Israel and to assess disease progression in HDV-coinfected versus HBV-monoinfected individuals. We hypothesized that HDV coinfection would be associated with a significantly increased risk of disease progression.
Methods
Study Design and Setting
We conducted a retrospective cohort study using electronic health records (EHRs) from Maccabi Healthcare Services (MHS), one of the largest healthcare organizations in Israel, providing comprehensive healthcare services to approximately 2.5 million members. MHS maintains a centralized, longitudinal EHR database with detailed clinical details, including diagnoses, laboratory results, medications, and demographic data.
Study Population
The study population included all individuals with chronic HBV infection identified within the MHS database between January 1, 2010, and December 31, 2021. Chronic HBV infection was defined as a positive HBV surface antigen (HBsAg) test result documented in the EHR for at least six months. Individuals were excluded if they had evidence of acute HBV infection (defined as a positive HBsAg test result followed by seroclearance within six months) or if they had incomplete demographic data. Within the cohort of individuals with chronic HBV, we identified those with HDV coinfection based on the presence of an HDV