It has been postulated that people with rheumatoid arthritis (RA) are at increased risk for infection after arthroplasty, but the extent if additional risk associated with treatment with biologic medications or corticosteroids is not well-defined. In a retrospective cohort study, researchers in the USA examined administrative data spanning early 2006 through to September 2015, examining records for adults with RA undergoing elective inpatient total knee or hip replacement (either primary or revision), and who had recently been treated with abatacept, adalimumab, etanercept, infliximab, rituximab, or tocilizumab (the biologics) before surgery. 10 923 surgical procedures were identified for 9911 patients treated with biologics. Outcomes were not radically different for people treated with each of the different biologics. There was an 8.16% risk for infection in hospital amongst those treated with abatacept, 6.87% with adalimumab, 8.90% with rituximab. Compared with a 1-year cumulative incidence of prosthetic joint infection of 2.14% with abatacept, the incidence was 0.35% with rituximab and 3.67% with tocilizumab.

On the other hand, treatment with steroids was associated with a dose-dependent increase in postoperative risk for infections. Propensity-weighted models showed that use of more than 10 mg of glucocorticoids per day (compared to no glucocorticoid use) resulted in a predicted risk for hospitalized infection of 13.25% (CI, 9.72% to 17.81%). The authors conclude that “Risks for hospitalized infection, prosthetic joint infection, and readmission after arthroplasty were similar across biologics. In contrast, glucocorticoid use, especially with dosages above 10 mg/d, was associated with greater risk for adverse outcomes.” See the original research, published in the Annals of Internal Medicine, here