Trends of Advanced Chronic Liver Disease Among 17,711 Persons in Mongolia During Years 2015-2023.

Chronic liver diseases cause a significant burden in Asia. This study aims to characterise the pattern and factors associated with advanced chronic liver disease (aCLD) in a large cohort from Mongolia, which has the highest rate of liver cancer globally. This is a cross-sectional analysis of HBsAg tested adults (≥ 18 years) with available liver stiffness measurement (LSM) and/or platelet count at initial visit at a hepatology centre, Ulaanbaatar, Mongolia during 2015-2023. Definition of aCLD was LSM ≥ 12.5 kPa or platelet count < 150*109 cells/L. The annual percentage change (APC) of the incidence rates and factors associated with aCLD were assessed via logistic regression models. Out of 17,711 persons identified, 2517 (14.2%) had aCLD at initial visit, with a mean age (±SD) of 50.1 (12.0) years, 23.6% below 40 years old and 53.2% were female. The prevalence of HBsAg+, anti-HDV+, HDV RNA+, and anti-HCV+ was 61.6%, 78.6%, 64.6% and 57.9% in aCLD, respectively. Among aCLD, three-fourths had an intermediate to high 5-year risk of hepatocellular carcinoma (HCC) with 25.0%, and 17.1% having previously received anti-HBV and anti-HCV therapies, respectively. The overall rate of aCLD declined (APC -7.8%), mainly due to decline in anti-HCV+ cases (APC -15.0%), while it significantly increased for anti-HDV+ over study period (APC 3.3%). In a large cohort of attendees at a hepatology centre in Mongolia, the prevalence of aCLD declined associated with decreasing HCV infection, while chronic hepatitis D constituted the majority of increasing cases. A minority received therapy, with most patients showing an intermediate to high risk of liver cancer. More efforts are needed to improve linkage to care and access to therapy, especially in middle-aged individuals at higher risk of liver disease progression.