Dissecting incidence and mortality inequalities of six types of liver diseases in 39 alcohol-dominant countries and 93 virus-dominant countries under the aging context: Insights from the Global Burden of Disease Study 2021

• The burden of chronic liver disease (CLD) and liver cancer (LC) is significantly higher in aging populations, with the highest incidence and mortality rates observed in individuals aged 60 years and above, highlighting the profound impact of population aging on liver disease burden. • This study categorizes 132 countries into alcohol-dominant (Region A, 39 countries), HBV-dominant (Region B, 60 countries), and HCV-dominant (Region C, 33 countries) regions, providing a novel etiology-region-specific analysis of the global burden of CLD and LC. • Viral hepatitis remains the leading cause of liver disease mortality, accounting for 56.1% of global CLD deaths and 67.7% of global LC deaths, while alcohol-related liver disease and liver cancer are more prevalent in alcohol-dominant regions. • Alcohol-induced chronic liver disease (CA) and liver cancer (LCA) are on the rise in countries like Romania and Ukraine (Region A), while HBV-induced chronic liver disease (CB) and liver cancer (LCB) are prevalent in Nigeria and Mali (Region B). In contrast, HCV-induced chronic liver disease (CC) and liver cancer (LCC) show high incidence and mortality rates in the Central African Republic and Libya (Region C). • Inequities in CLD are narrowing in Region A but intensifying in Regions B and C. LC is more burdensome in low-HDI countries, yet alcohol-related LC is increasing in high-HDI countries. Chronic liver disease (CLD) and liver cancer (LC) pose significant global health challenges affecting millions of people worldwide. An etiology-region-time specific understanding of their global burden is necessary. This study utilized data from the 2021 Global Burden of Disease Study, encompassing incidence, prevalence, mortality, and Disability-Adjusted Life Years (DALYs) attributed to CLD and LC. In 2021, global deaths from CLD and LC were 1,425 thousand and 483 thousand, respectively, with a decline in age-standardized death rates (ASDR) by 31.9% and 3.7% from 1990 to 2021. By categorizing the 21 regions into alcohol-dominant (Region A, 39 countries), HBV-dominant (Region B, 60 countries), and HCV-dominant (Region C, 33 countries), distinct health inequities emerged. In Region A, Romania and Ukraine face rising incidence and mortality rates due to alcohol-induced liver disease. In Region B, HBV-related rates are high in Nigeria and Mali, while China has reduced. Region C, including the Central African Republic and Libya, shows high HCV-induced rates, highlighting regional disparities. The incidence and mortality rates of CLD are negatively correlated with the Human Development Index (HDI), with varying regional trends. In Region A, health inequities have narrowed, while they have intensified in Regions B and C. Significant health inequities exist, with CB and CC burdens more concentrated in high-HDI countries where inequities are diminishing, whereas CA burdens are predominantly in low-HDI countries, where inequities are more pronounced. These findings highlight the urgent need to address health inequities in liver disease burden across specific regions.