Trends in cause-specific mortality among people with hepatitis C virus in New South Wales, Australia

Background

Monitoring of HCV-related morbidity and mortality is crucial to evaluate direct-acting antiviral (DAA) therapy impact and HCV elimination progress. This population-based study examined mortality among individuals with an HCV notification in New South Wales (NSW), Australia, including cause-specific mortality prior to and during the viral hepatitis elimination era (2015–2021).

Methods

HCV notifications in NSW, Australia (1995–2021) were linked to hospitalisation records and cause-specific mortality records. Over the period 2002–2021, all-cause and cause-specific mortality rates were examined. Cox proportional hazard models were used to assess factors associated with mortality during the viral hepatitis elimination era.

Results

Among people with HCV notifications in 1995–2021, 112,046 were alive during 2002–2021 and contributed to mortality analyses. All-cause mortality per 100,000 population increased from 5.5 in 2002 to 13.4 in 2015 and plateaued at 12.9 in 2021. Liver-related mortality per 100,000 population increased from 2.0 in 2002 to 5.9 in 2015, before declining to 4.6 in 2021. Drug-related mortality per 100,000 population increased from 0.7 in 2002 to 1.8 in 2015, before declining to 1.2 in 2021. Factors associated with increased mortality risk during 2015–2021 included: recent injecting drug use (adjusted Hazard Ratio [aHR] 7.22, 95 % CI 6.84–7.62) and recent alcohol use disorder (aHR 3.17, 95 % CI 2.97–3.37). Recent opioid agonist therapy (aHR 0.47, 95 % CI 0.43–0.51) and recent incarceration (aHR 0.32, 95 % CI 0.23–0.45) were associated with lower mortality risk.

Conclusion

During the HCV elimination era, both liver-related and drug-related mortality have declined, suggesting direct and indirect impacts of DAA therapy, respectively. Expanded opioid agonist therapy coverage and enhanced alcohol use disorder management could further reduce mortality.