Shwetha Thiyagarajan, Jarell Jie-Rae Tan, Rahul Kumar, Jessica Tan, Kenneth W. Lin, Nicholas Chin Hock Tee, Chin Kimg Tan, Andrew Xia Huang Tan, Daphne Shih Wen Ang, Jeannie Peng Lan Ong, Tiing Leong Ang, Andrew Kwek, Kwong Ming Fock, Yu Jun Wong
INTRODUCTION: The burden of autoimmune liver disease (AILD) is rising globally, yet data on its epidemiology and outcomes in Singapore remain limited. We aimed to characterise disease phenotype, treatment response and clinical outcomes among patients with autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC). METHODS: We retrospectively analysed patients diagnosed with AILD between 1995 and 2025 at a tertiary centre. Diagnoses and treatment responses for AILD were defined according to international guidelines. Clinical outcomes between AIH and PBC were compared using logistic regression, adjusted for baseline Model for End-stage Liver Disease score. RESULTS: Among 260 patients included, 71.2% had PBC, 22.0% had AIH, 3.8% had AIH/PBC overlap syndrome and 3.1% had PSC. The prevalence of AIH and PBC was 8.0 and 26.1 per 100,000 persons, respectively. Autoimmune hepatitis was independently associated with a higher risk of de novo steatotic liver disease (SLD) (adjusted odds ratio [OR] 5.90, 95% confidence interval [CI] 2.39-14.58). Compared with PBC, patients with AIH had a higher treatment response rate at 1 year (57.4% vs. 34.6%, P < 0.01) and a lower risk of overall mortality (OR 0.28, 95% CI 0.11-0.69). In patients with PBC, achieving a treatment response by the Toronto criteria was associated with improved transplant-free survival. CONCLUSION: The prevalence of AIH and PBC in our cohort mirrors that of East Asian populations. Despite a superior biochemical response, AIH was associated with a higher risk of hepatic steatosis. Underutilisation of second-line treatment in PBC represents an important gap for future improvement.