The global burden of alcohol use disorders: methodological considerations
Background: The Global Burden of Disease (GBD) project estimates the relative impact of health problems worldwide, providing comprehensive data for evidence-based decision making. However, its methodological approaches are not without controversy: emerging research has highlighted that limitations within the GBD framework disproportionately affect mental and substance use disorders, contributing to an underestimation of their disease burden. One such limitation is the attribution of burden to downstream causes instead of the underlying disorder itself. This is exemplified through the GBD’s approach to alcohol use disorders (AUD), where many of AUDs’ direct somatic consequences are distributed among various other aggregations (e.g. liver cancer due to alcohol use is grouped with neoplasms). This research aims to present estimates from an alternative methodology that partially corrects these biases.
Methods: 2019 GBD data was downloaded in the form of Disability Adjusted Life Years (DALY). The global burden of disease was re-estimated by re-allocating somatic manifestations of alcohol use (liver cancer due to alcohol use, alcoholic cardiomyopathy, and cirrhosis due to alcohol use) to AUDs. Burden was analysed across the lifespan, and age-standardized rates of mental and substance use disorders were ranked for men and women.
Results: In the GBD framework, AUDs comprise 0.7% of DALY burden. When accounting for somatic consequences of alcohol use, the burden nearly doubles to 1.3%. Burden due to AUDs peaks between 40-44 years of age, where it comprises 2.7% of DALYs. AUDs are the highest contributor to DALYs of all mental and substance use disorders for men, and they rank fifth for women.
Conclusion: While there is no perfect solution to the underestimation of AUDs and other mental and substance use disorders, we must work towards methodological improvements to avoid exacerbating the lack of prioritization of conditions that have historically been neglected by policymakers and funders.