Long-term Outcomes after Steroid Pulse Therapy in Patients with Type 1 Autoimmune Pancreatitis

Objective Steroid pulse therapy is a regimen involving the intravenous administration of supra-pharmacological doses of corticosteroids in the short term. It is used to treat various inflammatory and autoimmune conditions. However, the strengths and limitations of steroid pulse therapy for induction of remission in type 1 autoimmune pancreatitis (AIP) are unknown. Methods Depending on the steroid therapy regimen administered, the 104 patients with type 1 AIP included in this retrospective study were divided into three groups: conventional oral prednisolone (PSL) regimen (PSL group), intravenous methylprednisolone (IVMP) pulse followed by oral PSL regimen (Pulse+PSL group), and IVMP pulse-alone regimen (Pulse-alone group). We then examined the relapse rate and adverse events among the three groups. Results The Kaplan-Meier estimates of the relapse rate at 36 months after steroid therapy were 13.6% in the PSL group, 13.3% in the Pulse+PSL group, and 46.2% in the Pulse-alone group. The log-rank test revealed that the relapse-free survival in the Pulse-alone group was significantly shorter than that in the PSL (p=0.024) and Pulse+PSL groups (p=0.014). The exacerbation of glucose tolerance after steroid therapy was less frequently observed in the Pulse-alone group (0%) than in the PSL group (17%, p=0.050) and Pulse+PSL groups (26%, p=0.011). Conclusion Although treatment with IVMP pulse alone resulted in unsatisfactory relapse prevention outcomes compared with conventional steroid therapy, the IVMP pulse-alone regimen might be an alternative treatment strategy for type 1 AIP from the perspective of avoiding adverse events from steroids.