The contribution of alcohol-use disorder to decompensated cirrhosis among people with hepatitis C: an international study

BACKGROUND: The aim of this study was to evaluate the contribution of alcohol-use disorder to hepatitis C virus (HCV)-related decompensated cirrhosis diagnosis in three settings.

METHODS: HCV notifications from British Columbia (BC), Canada, New South Wales (NSW), Australia, and Scotland (1995-2011/2012/2013, respectively) were linked to hospital admissions (2001-2012/2013/2014, respectively). Alcohol-use disorder was defined by non-liver-related hospitalisation due to alcohol use. Age-standardised decompensated cirrhosis incidence rates were plotted, associated factors were assessed using Cox regression, and alcohol-use disorder-associated population attributable fractions (PAFs) were computed.

FINDINGS: Among 58,487, 84,529, and 31,924 people with HCV in BC, NSW, and Scotland, 2,689 (4.6%), 3,169 (3.7%), and 1,375 (4.3%) had a decompensated cirrhosis diagnosis, and 28%, 32%, and 50% of those with decompensated cirrhosis had alcohol-use disorder, respectively. Age-standardised decompensated cirrhosis incidence rates were considerably higher among people with alcohol-use disorder in NSW and Scotland. Decompensated cirrhosis was independently associated with alcohol-use disorder in BC, aHR 1.92, 95% CI 1.76, 2.10; NSW, aHR 3.68, 95% CI 3.38, 4.00, and; Scotland, aHR 3.88, 95% CI 3.42, 4.40. The PAFs of decompensated cirrhosis-related to alcohol-use disorder were 13%, 25%, and 40% in BC, NSW, and Scotland, respectively.

INTERPRETATION: Alcohol-use disorder was a major contributor to HCV liver disease burden in all settings, more distinctly in Scotland. The extent to which alcohol use would compromise the individual and population level benefits of direct-acting antiviral therapy (DAA) needs to be closely monitored. Countries, where appropriate, must develop strategies combining DAA treatment uptake promotion and alcohol-use disorder management, if World Health Organization 2030 HCV mortality reduction targets are to be achieved.

LAY SUMMARY: The burden of advanced liver disease has been rising among people with hepatitis C globally. The prospect of increased access to direct-acting antiviral (DAA) therapies instigated the World Health Organization (WHO) to set ambitious targets for elimination of hepatitis C as a major public health threat by 2030. However, continued heavy alcohol intake is likely to impact potential benefits of DAA-based cure on individual-level liver disease progression and population-level liver disease burden. The aim of this study was to evaluate the contribution of alcohol-use disorder to hepatitis C-related decompensated cirrhosis diagnosis in British Columbia, Canada, New South Wales, Australia, and Scotland. Alcohol-use disorder was a major contributor to hepatitis C-related liver disease burden in all settings, more distinctly in Scotland. The extent to which alcohol use would compromise the individual and population level benefits of DAA-based therapies needs to be closely monitored. Countries, where appropriate, must develop strategies combining DAA treatment uptake promotion and alcohol-use disorder management, if WHO 2030 hepatitis C mortality reduction targets are to be achieved.