Risk factors associated with relapse of type 1 autoimmune hepatitis in Japan.

Aim:   Patients receiving corticosteroid therapy on a tapered schedule occasionally suffer autoimmune hepatitis (AIH) relapses. The aim of this study was to assess the frequency and features of relapses, explore risk factors associated with relapses, and evaluate the effectiveness of azathioprine (AZP) therapy against relapses in Japanese patients with type 1 AIH.

Methods:   We assessed clinical characteristics and therapeutic processes in 67 patients diagnosed with AIH.

Results:   Twenty patients (29.9%) suffered from relapses during tapering of corticosteroid therapy. The remaining 47 patients sustained their remission. At the onset of disease, risk factors associated with relapse were: age of 50 years or older; total bilirubin of 1.5 mg/dL or more; aspartate aminotransferase levels of 250 IU/L or more; alanine aminotransferase levels of 250 IU/L or more; prothrombin activity of 80% or more; γ-globulin levels of 3.4 g/dL or more; and International Autoimmune Hepatitis Group (IAIHG) score of 17 or more in univariate analysis. Grading of histological interface hepatitis is not significantly associated with relapse. Multivariate analysis revealed that IAIHG scores of 17 or more were significantly associated with relapse (odds ratio = 6.57, 95% confidence interval = 1.19-36.33). Seven patients who relapsed were treated with AZP and prednisolone (PSL), and all sustained remission (100%). Of the remaining 13 relapse patients who received only PSL, eight (61.5%) suffered additional relapses.

Conclusion:   Our results demonstrate the risk factors associated with relapse of AIH. We also show that early administration of AZP after the first relapse may help to prevent additional relapses.