Complications after orthopaedic surgeries in patients with rheumatoid arthritis treated with Janus kinase inhibitors: A retrospective observational study.

OBJECTIVES: The current study compared the outcome after orthopaedic surgeries in patients with rheumatoid arthritis receiving Janus kinase inhibitors (JAKis) versus biologic disease-modifying anti-rheumatic drugs (bDMARDs). METHODS: This was a retrospective observational study of Japanese patients with rheumatoid arthritis. Sixty-two patients with rheumatoid arthritis using JAKi preoperatively underwent orthopaedic surgeries. Using propensity score matching, these 62 patients were matched with 62 patients using bDMARDs preoperatively. The number of adverse events was counted. We also examined whether the drug-withholding period in the JAKi-treated group was associated with the occurrence of major postoperative adverse events, namely inflammatory flares and delayed wound healing. RESULTS: JAKi-treated patients had a higher incidence of postoperative flares than bDMARD-treated patients (29% versus 12.1%, P = .01). The incidences of postoperative complications other than flares were not significantly different between the two groups. Among the JAKi-treated group, a longer perioperative drug-withholding period (≥11 days) was associated with a higher incidence of postoperative flares (P = .04). The incidences of delayed wound healing and surgical site infection were not associated with the duration of the JAKi-withholding period. CONCLUSIONS: JAKi-treated patients had a higher incidence of postoperative flares than bDMARD-treated patients. A total of ≥11 days of drug withdrawal was associated with postoperative flares.

Synovial-tissue resident macrophages play proinflammatory functions in the pathogenesis of RA while maintaining the phenotypes in the steady state.

Synovial tissue-resident macrophages (STRMs) maintain normal joint homeostasis in a steady state. However, it is unclear whether STRMs still play homeostatic roles or change the functions in the joint of rheumatoid arthritis (RA), where infiltrating peripheral blood monocyte-derived macrophages (PBMoMs) play proinflammatory roles. In the present study, we examined changes in the phenotypes and functions of STRMs in response to RA-related stimuli in vitro. STRMs were prepared from non-inflammatory osteoarthritis (OA) joint synovium, which is histologically indistinguishable from normal joint synovium. PBMoMs were prepared and used for comparison. After stimulation with plate-bound IgG, which mimics anti-citrullinated protein antibody immunocomplex formed in RA joints, or with combinations of RA-related inflammatory mediators, namely tumor necrosis factor-α (TNF-α) and prostaglandin E2 or interferon-γ, PBMoMs downregulated surface markers and genes associated with anti-inflammatory macrophages, and upregulated cytokine and marker genes of proinflammatory macrophages in RA. On the other hand, STRMs hardly changed the expression of surface molecules and marker genes but altered the pattern of cytokine gene expression after stimulation like PBMoMs. Furthermore, in vitro stimulated STRMs promote proinflammatory functions of cocultured synovial fibroblasts. Thus, STRMs might play proinflammatory roles in RA joints, while maintaining their phenotypes in the steady state.