Relation of NSAID, DMARD and TNF-inhibitors for Ankylosing Spondylitis and Psoriatic Arthritis to Risk of Total Hip and Knee Arthroplasty

Objective Ankylosing spondylitis and psoriatic arthritis (AS/PsA) often affect the hip and/or knee. If effective, treatments might reduce risk of total hip or total knee arthroplasty (THA/TKA). We evaluated risk of THA/TKA related to use of medical therapies in AS/PsA. Methods We conducted a nested case-control study using 1994-2018 data from the OptumLabs® Data Warehouse, which includes de-identified medical and pharmacy claims, laboratory results, and enrollment records for commercial and Medicare Advantage enrollees. Among those with AS/PsA, THA/TKA cases were matched up to 4 controls by sex, age, AS/PsA diagnosis, diagnosis year, insurance type, obesity and prior THA/TKA. We assessed AS/PsA treatment 6 months prior to THA/TKA, including disease-modifying anti-rheumatic drug (DMARD) and tumor necrosis factor inhibitor (TNFi), alone or in combination, stratified by NSAID use. We evaluated the relation of treatment to risk of THA/TKA using conditional logistical regression with adjustment for confounders. Results Among 16,748 adults with AS, there were 444 THA/TKA cases, and 1,613 matched controls. Among 34,512 adults with PsA, there were 1,003 cases and 3,793 controls. Adjusted odds ratios for treatment category and THA/TKA ranged from 0.60 to 1.92, however none was statistically significant. Results were similarly null in several sensitivity analyses. Conclusion Odds of THA/TKA were not reduced with any combinations of NSAIDs, DMARDs, or TNFi among persons with AS or PsA. Given current utilization patterns in this population of US adults with AS and PSA, these medical therapies did not appear to be associated with less end stage peripheral joint damage.