Treatment strategies for relapsing IgG4-RD: twelve-year experience from a prospective cohort.

OBJECTIVES: Relapse is common in IgG4-related disease (IgG4-RD). While previous studies focus on treatments for active IgG4-RD, data on the management of relapsing IgG4-RD remains limited. We aimed to investigate the treatment strategies for relapsing IgG4-RD. METHODS: This study analyzed data prospectively collected from an IgG4-RD cohort, including patients who experienced their first relapse and were followed for over 12 months. We compared the outcome among three groups: (1) Intensifying glucocorticoids (GC) only; (2) Intensifying immunosuppressants (IM) only; (3) Intensifying both GC and IM. The primary outcome was recurrent relapses. A decision tree model was developed to predict recurrent relapses. RESULTS: A total of 259 patients with IgG4-RD was included, with a male predominance (61.7%) and a median age of 54.0 years. Patients who intensified both GC and immunosuppressants (IM) (adjusted p 0.0002, HR 0.29, 95% CI: 0.16-0.52) experienced less relapses compared to those who intensified IM alone, while those who only intensified GC had a tendency to experience less relapses (adjusted p 0.0823, HR 0.51, 95% CI: 0.26-1.03). These differences were more pronounced in the subgroup with internal organ involvement. The decision tree indicated that those with an RI decrease to ≤ 2 and an IgG4 decrease ≥25% after treatment were more likely to stay free from recurrent relapses, with an AUC of 0.728 in the testing set. CONCLUSION: When treating relapse in IgG4-RD, GC-based treatment was associated with a lower hazard of recurrent relapse compared with only adjusting IMs, especially for those with internal organ involvement.