A study, published in The Annals of the Rheumatic Diseases, examined the impact of biological disease-modifying anti-rheumatic drugs and associated rheumatoid arthritis management guidelines on total hip and knee replacement incidence rates in Denmark.
René Lindholm Cordtz, PhD, of Copenhagen, Denmark-based Center for Rheumatology and Spine Diseases, and colleagues reviewed a nationwide cohort of patients and conducted an interrupted time-series analysis.
Researchers identified 30,404 patients with RA and 297,916 controls.
Here's what they found:
1. In 1996, the incidence rate of total hip and total knee replacements among patients with RA was 8.72 and 5.87, respectively. Among controls, it was 2.89 and 0.42, respectively.
2. From 1996 until 2016, the incidence rate of total hip replacements decreased among RA patients, but increased among the control group.
3. Concerning total knees, incidence rate increased in the RA group from 1996 until 2001, and then decreased from 2003 through 2016 because of the introduction of biological disease-modifying anti-rheumatic drugs.
Knee replacement incidence rates among the control group increased from 1996 through 2016.
Researchers concluded, "We report that the incidence rate of THR and TKR was 3-fold and 14-fold higher, respectively among patients with RA compared with [general population comparators] in 1996. In patients with RA, introduction of bDMARDs was associated with a decreasing incidence rate of TKR, whereas the incidence of THR had started to decrease before bDMARD introduction."