Epidemiology and natural history of chronic Hepatitis B in the Canadian province of Alberta from 2012 to 2021: A population-based study

Abstract

Introduction and Objectives: There are limited recent data on the burden of chronic hepatitis B (CHB) in the North American general population. We aimed to identify the CHB burden from a Canadian population-based perspective. Patients and Methods: Using a retrospective cohort design, we searched Alberta Analytics administrative databases including the Provincial Laboratory database, to describe CHB epidemiology and natural history in Alberta, Canada between fiscal years 2012-2020. We analyzed incidence and prevalence trends using a Poisson regression model and conducted Kaplan-Meier analyses to examine the incident cohort's survival. Results: The age/sex-adjusted incidence of CHB between 2015-2020 was 27.1/100,000 person/years (29.6/100,000 in males and 24.5/100,000 in females) and was highest among individuals aged 45-64 years. Despite a decrease in annual incidence of CHB from 36.4 to 13.4/100,000 between 2015-2020, prevalence increased from 98.9 to 210.3/100,000 in the same period. Of 6,860 incident cases, 2.1% died, and 0.2% underwent liver transplantation during a median follow-up of 3.6 years (interquartile range 2.0-4.9 years). CHB patients had significantly lower survival rates compared to age/sex-matched Canadians, with a standardized mortality ratio of 3.9 (95% confidence interval [CI] 3.3-4.6). Male sex (hazard ratio [HR] 1.7; 95% CI 1.2-2.5), older age at diagnosis (HR, 1.08; 95% CI 1.07-1.09) independently predicted mortality. Conclusions: CHB incidence decreased in Alberta, which is consistent with nationwide trends. Males and individuals aged 45-64 had higher CHB incidence and prevalence. CHB patients’ lower survival rates emphasize the need to address barriers to guideline recommended HBV care linkage.

Keywords

• Hepatitis B
• Epidemiology
• Incidence
• Prevalence
• Natural history
• Survival