The Impact of Race/Ethnicity on the Clinical Epidemiology of Autoimmune Hepatitis

Goals: To evaluate race/ethnicity-specific variations in autoimmune hepatitis (AIH) with a focus on Asians and Hispanics, the fastest growing populations in the United States. Background: AIH is a chronic inflammatory disease in which race/ethnicity-specific variations in clinical epidemiology have been reported. However, earlier studies were small or did not include a comprehensive analysis of Asians and Hispanics, the 2 fastest growing population cohorts in the United States. Study: A retrospective study analyzing patient data from 1999 to 2010 in a large tertiary-care community hospital to assess AIH epidemiology among a racially diverse population. Results: One hundred eighty-three patients with AIH were included in the study with 81 patients having "definite" AIH by International Autoimmune Hepatitis Group criteria and 63 were diagnosed with overlap syndromes. Women and whites were the largest cohorts. The average age of diagnosis was similar among all groups. Biopsy-confirmed cirrhosis was present in 34% of AIH patients with Hispanics demonstrating the highest prevalence of cirrhosis (55%). When compared with whites, Asians had higher international normalized ratio (INR) (1.4U vs. 1.1 U, P < 0.01), and Hispanics had lower serum albumin (3.3 g/dL vs. 3.7 g/dL, P < 0.001) and platelets (123.8 thousand/mcL vs. 187.5 thousand/mcL, P < 0.001) and higher international normalized ratio (1.5U vs. 1.1 U, P = 0.05). Kaplan-Meier survival analysis demonstrated a trend toward worse outcomes among Asians. Conclusions: Among AIH patients, Hispanics had the highest prevalence of cirrhosis, and Asians had poorer survival outcomes. Race/ethnicity-specific disparities in AIH epidemiology may reflect underlying genetic differences, contributing to variations in disease severity, response to therapy, and overall mortality.