Paradoxical adverse events of anti-tumour necrosis factor therapy for spondyloarthropathies: a retrospective study

Methods. Since 2000, we have followed 296 patients with SpA [198 AS, 21 SpA associated with IBD (9 ulcerative colitis, 12 Crohns disease) and 77 psoriatic arthritis] treated with at least one anti-TNF drug (infliximab, etanercept or adalimumab), and 112 SpA patients treated only with conventional DMARDs who served as controls. Considering the cumulative time of exposure to each anti-TNF agent, the frequencies of new-onset PAEs in exposed patients were calculated. Results. Respective cumulative exposure times were 287, 290 and 62 patient-years for infliximab, etanercept and adalimumab. We observed the following PAEs: five psoriasis (three under infliximab and one with etanercept or adalimumab), three AAU (1/100 patient-years, all under etanercept) and four IBD (three under etanercept and one under infliximab). There was no significant association among any of these PAEs and a specific anti-TNF agent; nor significant difference in the overall PAEs among patients receiving anti-TNF drugs or controls (P0.303), the latter experiencing two psoriasis and three AAU. Conclusions. Undesirable side effectsIBD, AAU and psoriasismay appear with anti-TNF drugs. Even if they are, a priori, paradoxical, no evidence supports any PAEs to be anti-TNF agent-specific in SpA.