Autoimmune Hepatitis and Overlap Syndrome Among Alaska Native People: Prevalence, Clinical Characteristics, and Remission

Background And Aim: High autoimmune hepatitis (AIH) and overlap syndrome (OS) prevalence have been previously documented among Alaska Native people. The purpose of this project is to report changes in AIH/OS prevalence over time, clinical characteristics, and factors associated with biochemical remission.

Methods: We reviewed medical records for Alaska Native/American Indian (AN/AI) patients diagnosed with AIH/OS between 1984 and 2021. Point prevalence was calculated based on AIH/OS patients alive at the end of 2021 and at 5-year intervals from July 1, 2000, to July 1, 2020.

Results: We identified 189 AN/AI persons diagnosed with AIH or OS (157 AIH, 32 OS). Of these 189, 137 were alive at the end of 2021 for a point prevalence of 91.2 per 100 000 (95% confidence interval [CI]: 77.2-107.8)-75.9 (95% CI: 63.2-91.2) for AIH and 15.3 (95% CI: 10.2-23.0) for OS. Prevalence for both AIH and OS has risen steadily since 2000. Eighty-nine consented participants (62.7%) achieved biochemical remission with a median time from diagnosis to start of remission of 1.9 years (IQR 0.5-5.0 years). Consented patients with fatty liver were less likely to achieve remission, but their time to remission was shorter than for patients without fatty liver.

Conclusion: The AN/AI population in Alaska continues to have the highest reported prevalence of AIH/OS in the world, with prevalence rising steadily since 2000. High reported AIH/OS prevalence is likely due in part to strong referral networks for liver disease. Detection and treatment can lead to biochemical remission and improved health outcomes.