Risk of Neuroinflammatory Diseases Among New Recipients of Biologic and Targeted Synthetic Disease-Modifying Antirheumatic Drugs.

Objective: Neuroinflammatory adverse events have been observed among new users of tumor necrosis factor (TNF) inhibitors. No studies to date have compared the real-world risk of TNFs with other new users of biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs). The objective of this study is to describe the risk of neuroinflammatory disease after initiation b/tsDMARDs.

Methods: This new user comparative effectiveness cohort study used a large US-based electronic health records database to describe the unadjusted incidence of neuroinflammatory adverse events over a 3-year period. The cohort included patients with rheumatoid arthritis, psoriasis, psoriatic arthritis, ankylosing spondylitis, Crohn's disease, or ulcerative colitis initiating treatment with a TNF inhibitor (n = 93,661) or other b/tsDMARD (n = 38,354).

Results: Among 132,015 patients included in the analysis, the most common first biologic agent was a TNF inhibitor; the unadjusted incidence of neuroinflammatory events was numerically lower among new users of TNF inhibitors (incidence 1.34 per 1,000 patient-years) as compared with the combined non-TNF group (1.69 per 1,000 patient-years). There was no significant association between TNF exposure and neuroinflammatory events as compared with the combined non-TNF b/tsDMARDs overall (hazard ratio 1.01; 95% confidence interval 0.75-1.36) and within each disease group.

Conclusion: The overall risk of neuroinflammatory events among new users of TNF inhibitors did not differ substantially as compared with new users of other b/tsDMARDs. Meta-analyses of randomized trials should be conducted to corroborate these findings, which may be affected by channeling bias.