Objective Metabolic-associated fatty liver disease (MAFLD) has only recently been proposed; therefore, the characteristics of patients with autoimmune hepatitis (AIH) and MAFLD remain unclear. This study evaluated the effect of MAFLD on AIH patients with AIH. Methods We reevaluated the Japanese Nationwide Survey of AIH in 2018, which involved a survey of patients diagnosed with AIH between 2014 and 2017. We categorized patients with AIH according to the presence or absence of MAFLD and compared the clinical characteristics between the two groups. Results A total of 427 patients (77 men and 350 women) were included in this study. The overall prevalence of MAFLD was 10.5%. Compared to AIH patients without MAFLD, AIH patients with MAFLD had the following characteristics at the time of the AIH diagnosis: (1) a higher body mass index, (2) a higher prevalence of hypertension, (3) mild elevation of hepatobiliary enzymes and total bilirubin, and (4) histologically progressive fibrosis. However, the levels of hepatobiliary enzymes and total bilirubin after treatment were significantly higher in AIH patients with MAFLD than in those without MAFLD. Conclusions AIH patients with MAFLD had characteristics different from those of AIH patients without MAFLD. These findings could help increase our understanding of patients with AIH with MAFLD.
Keywords: AIH; MAFLD; nationwide survey.