1036: Factors Associated With Long-term Remission After Drug Discontinuation In IgG4-related Disease: A 3-Year Rule

Background/Purpose: IgG4-related disease (IgG4-RD) is a chronic fibroinflammatory disorder with multi-organ involvement and elevated serum IgG4 levels. Glucocorticoids (GC) with or without immunosuppressants (IM) are the first-line treatment. GC/IM discontinuation carries a 23-41% relapse risk, but prolonged use increases infection risk, making cessation timing crucial. However, identifying patients who can achieve long-term remission remains challenging. This study aimed to investigate the characteristics of patients with and without relapse, identifying factors associated with long-term remission.

Methods: We conducted a retrospective study in China, screening 808 patients diagnosed with IgG4-RD. Eighty patients who achieved clinical remission before drug discontinuation were included in the study. Based on relapse records from the third year after drug cessation, patients were classified into no-relapse group (n = 37) and relapse group (n = 43). All patients fulfilled the 2019 ACR/EULAR classification criteria for IgG4-RD. We analyzed demographic characteristics, laboratory results, clinical symptoms, and treatment data at baseline and during follow-up.

Results: Univariate analysis indicated that the no-relapse group had a lower number of affected organs (p=0.014), family history of allergy (p=0.017), and family history of malignancy (p=0.042). Laboratory findings revealed lower serum levels of eosinophils (p=0.001) and IgG4 (p=0.006) in the no-relapse group at baseline. Patients from the relapse group exhibited higher rates of submandibular (p = 0.009) and parotid glands involvement (p = 0.001).


Additionally, the relapse group had more patients without IM prescriptions (p = 0.006). Before complete medication withdrawal, the relapse group exhibited higher serum IgG4 levels (2190 g/L) than the no-relapse group (1250 g/L, p = 0.037).

Cox regression analysis identified no salivary gland involvement (HR 3.26, 95% CI: 1.32-8.06, p = 0.012) and initial IM use (HR 0.41, 95% CI: 0.20-0.84, p = 0.017) as significant protective factors (Figure 1). Figure 2 visualized the distribution of relapsed organs. Kaplan-Meier analysis revealed a biphasic relapse pattern following treatment discontinuation, characterized by a plateau after 36 months (Figure 3). These findings suggest that patients remaining relapse-free for 3 years tend to attain durable remission.

Conclusion: IgG4-RD patients without salivary gland involvement and receiving an IM prescription at baseline demonstrated a reduced likelihood of disease relapse following treatment cessation. Furthermore, patients maintaining relapse-free status for 3 years post-treatment exhibited a 94.6% probability of achieving long-term remission, suggesting this timepoint as a meaningful predictor of sustained treatment efficacy.