Résumé
Objective: to investigate the risk of diverticulitis and gastrointestinal perforation (GIP) in patients with rheumatoid arthritis (RA) treated with tocilizumab (TCZ) compared to rituximab (RTX) and abatacept (ABA). Methods: we conducted a population-based study using three observational french registries evaluating the effectiveness and the safety of RTX, ABA, and TCZ in RA patients. Using a propensity score approach, we compared the risk of diverticulitis or GIP in these patients.Results: twenty-one vs 20 diverticulitis (corresponding incidence = 5.3 vs 2.3/1000 person-years) and 9 vs 10 GIP (2.3 vs 1.1/1000 person-years) occurred respectively in TCZ treated patients (n=1496) compared to RTX or ABA (n=3005). Based on inverse probability weighting, there were an increased risk of diverticulitis (OR 4.16 [95% CI 2.66-6.50]) and GIP (3.96 [2.18-7.20]) in TCZ treated patients compared to RTX and ABA. In a subgroup analysis, we observed an increased risk of GIP due to diverticulitis but not to any other etiology. Compared to RTX and ABA, diverticulitis and GIP among TCZ patients occurred earlier after the last perfusion (p=0.01), with atypical clinical presentation (slow transit in 30%, p=0.04) and lower acute phase reactants when the event occurred (C-reactive protein: 31.2±58.4 vs 88.2±89.6 mg/L, p=0.005).Conclusion: TCZ was associated with an increased risk of diverticulitis, GIP and GIP due to diverticulitis but not to other etiologies compared to RTX and ABA. Our study confirmed an increased risk of GIP in RA patients treated with TCZ that could be explained by an increased risk of diverticulitis with disconcerting clinical presentation.