Outcome and risk factors for progression in IgG4-related disease under watchful waiting

This study aimed to explore the risk factors for progression in immunoglobulin G4-related disease (IgG4-RD) under watchful waiting and the temporal distribution of progression events to inform clinical decision-making.

A total of 40 IgG4-RD patients managed with the watchful waiting strategy were identified and included. Patients were categorised into 'without internal organ involvement' (WOI, n=26) and 'with internal organ involvement' (WI, n=14) groups. Baseline characteristics and progression rates were compared. Risk factors for progression were further identified using logistic and Cox regression analyses in the WOI group. The distribution of time to disease progression was summarised.

Progression occurred in 12/40 patients (5 in WOI vs. 7 in WI). Kaplan-Meier analysis showed a significantly higher stability probability in the WOI group (p=0.048). Paranasal sinus involvement, high response index (RI), elevated eosinophil percentage (Eos%), and high IgE levels were significant risk factors for progression in WOI group. Notably, all progression events occurred within the first year of follow-up, with the estimated hazard function peaking at 6 to 8 months and declining thereafter.

IgG4-RD patients with internal organ involvement exhibit a higher rate of disease progression under watchful waiting. Paranasal sinus involvement, high RI, high Eos%, and high IgE levels were identified as potential risk factors for disease progression. Intensive surveillance is especially warranted during the early phase.