Hospitalization related to chronic hepatitis B and C in recent immigrants in Canada: An immigration administrative data-linked, population-based cohort study

Abstract

Background: Canadian immigrants from countries where the hepatitis B virus (HBV) and hepatitis C virus (HCV) are endemic may be at higher risk of liver-related disease than Canadian-born residents. This study compared HBV- and HCV-related hospitalizations in Canadian immigrants (arriving from 1980 to 2013) and long-term residents (Canadian-born population and pre-1980 immigrants) and aimed to describe the burden of disease in both groups.

Methods: Based on the 2004/2005-to-2013/2014 hospital Discharge Abstract Database linked to the 1980-to-2013 Longitudinal Immigration Database, this descriptive cross-sectional study examined the distribution of HBV- and HCV-related hospitalizations, lengths of stay, comorbidities, and sequelae incurred by immigrants and long-term residents in Canada. With a linkage rate of 85%, 5,854,949 immigrants were included in the study. Proportions of HBV- and HCV-related hospitalizations attributable to immigrants were calculated.

Results: By birth country risk level, 22% of HBV-related hospital events among recent immigrants, and 20% of those related to HCV, were among people from high-risk countries. Proportionally, fewer immigrants had comorbidities than long-term residents. The top two hospital-related sequelae in both groups were cirrhosis and ascites, and liver cancer. While immigrants made up 16% of the Canadian population, they incurred 37% of HBV-related hospitalizations and 9% of HCV-related hospitalizations, giving ratios of hepatitis-related hospitalizations relative to the population share of 2.3 (95% confidence interval [CI]: 2.2 to 2.5) and 0.5 (95% CI: 0.5 to 0.6) respectively. These ratios were higher among seniors, at 4.4 (95% CI: 3.9 to 4.9) and 2.3 (95% CI: 1.9 to 2.6), respectively.

Interpretation: Immigrants can require hospitalization for hepatitis in Canada, especially for HBV. These results may inform health screening for HBV or HCV in the Canadian immigration context.

Keywords: global health; health policy; infectious diseases; public health; research methods; statistics.