Background Studies have shown that rheumatoid arthritis (RA) patients are at increased risk of prosthetic joint infection (PJI) but with non-uniform results for mortality risk, following total hip and knee arthroplasty (THA and TKA, respectively). The impact of biological DMARD (bDMARD) treatment on the risk of these outcomes is unknown.
Objectives To investigate the risk of revision, PJI and death following THA and TKA in 1) RA compared with osteoarthritis (OA) patients and 2) RA patients treated with bDMARDs compared with those not.
Methods Register-based cohort study linking the National Patient Register, DANBIO, Danish Hip Arthroplasty Register and Danish Knee Arthroplasty Register.
Follow-up: from date of THA/TKA to date of any of the outcomes, to 10 years of follow-up or end of 2014, whichever came first.
Statistics: Fine-Gray competing risks analyses to calculate confounder adjusted sub-Hazard Ratios (aSHR) with 95% confidence intervals (95% CI) for revision and PJI; Cox proportional hazard models to calculate aHR for risk of death.
Results We identified 3913 RA and 120 499 OA patients. In DANBIO, 360 bDMARD and 1586 not-bDMARD treated RA patients were eligible for analysis. See Table for results.
Conclusions We report an increased risk of death and PJI but a lower risk of revision in patients with RA compared with OA following THA and TKA. In RA patients, prednisolone, but not bDMARD treatment within the year prior and/or following THA and TKA was associated with an increased risk of death.
Disclosure of Interest R. Cordtz: None declared, L. E. Kristensen: None declared, S. Overgaard Speakers bureau: Pfizer, AbbVie, Amgen, UCB, Celgene, BMS, MSD, Novartis, Eli Lilly, Janssen Pharmaceuticals, A. Odgaard: None declared, H. Lindegaard: None declared, L. Dreyer Consultant for: LD has received fees for speaking and consultancy by MSD, UCB and Janssen pharmaceuticals.