Hepatic and Extrahepatic Characteristics of Autoimmune Hepatitis: A 23-year Hospital-Based Cohort Study

Background: The characteristics of autoimmune hepatitis (AIH) in Asia mostly remain elusive. Methods: A cohort study of liver biopsy-proven AIH patients was conducted in a tertiary care cancer of Taiwan. Results: From 1999 to 2022, of 13,766 patients who underwent liver biopsy, 150 patients with AIH were enrolled. The female-to-male ratio was 2.26. At baseline, the mean age was 51.09 years, mean alanine aminotransferase level was 494.11 U/L, and 17 (11.3%) had cirrhosis. All except one patient had AIH type 1. The females were older and had higher baseline cirrhosis rates than did the males. The 23-year cumulative incidences of cirrhosis, hepatocellular carcinoma (HCC), mortality/liver transplantation, autoimmune diseases and extrahepatic cancer were 64.2%, 13.3%, 23.4%, 30.7% and 21.2%, respectively. The 1-year, 2-year, 3-year, 5-year, 10-year and 20-year postimmunosuppressive therapy relapse rates were 60%, 78.2%, 81.8%, 89.1%, 94.5% and 100%, respectively. Baseline associations were as follows: alkaline phosphatase (Alk-p) levels with postimmunosuppressive therapy flare [hazard ratio (HR): 1.003; 95% CI HR: 1.000-1.005]; age with HCC (1.072; 1.010–1.138) and all-cause cancer (1.041;1.005–1.079); cirrhosis with mortality/liver transplantation (11.933;1.984–71.787); and antinuclear antibody (ANA) titers with mortality/liver transplantation (1.001;1.000-1.003), cirrhosis (1.001;1.000-1.002), and autoimmune diseases (1.001; 1.000-1.002). Conclusion: In an Asian country endemic for viral hepatitis, the female-to-male and baseline cirrhosis rates of AIH patients were lower than expected, while over 60% of the patients eventually developed cirrhosis. The high posttherapy relapse rate warrants cautious monitoring, particularly for patients with high baseline Alk-p levels. Baseline age, cirrhosis status and ANA titers are crucial for outcomes.