Persistent normalization of serum alanine aminotransferase levels improves the prognosis of type 1 autoimmune hepatitis

Background/Aims Autoimmune hepatitis shows a good response to immunosuppressive treatment, and the prognosis may be determined by the clinical course. The present study was conducted in order to analyze the factors contributing to the outcomes of patients with type 1 autoimmune hepatitis. Methods Eighty-four consecutive patients with type 1 autoimmune hepatitis were followed up regularly for a median follow-up period of 70.5 months (16.2–163 months). We analyzed the prognostic factors using time-fixed and time-dependent Cox proportional hazard models. The end point was progression of the disease to decompensated liver cirrhosis. Results Seventy-seven patients (92%) were treated with prednisolone during the follow-up period, and 11 patients (13%) developed decompensated liver cirrhosis. Using a time-dependent multivariate model, the starting dose of corticosteroid (dose of prednisolone <20 mg/day), relapse within 3 months after the normalization of serum alanine aminotransferase levels with initial treatment, and elevated serum alanine aminotransferase levels during the follow-up period (>40 IU/L), all showed a significant association with progression of the disease. Conclusions The prognosis of type 1 autoimmune hepatitis on adequate immunosuppressive treatment improves when the serum alanine aminotransferase level persists at ≤40 IU/L. Factors existing prior to medical treatment may not affect the prognosis.