To determine if NSAID use was different between OA (hip and/or knee) patients treated surgically to those treated medically.
We conducted a case control study, in which cases (n = 433) had had a total joint replacement within a two-year period, while controls (n = 195) had seen a rheumatologist or orthopedic surgeon, and not been recommended for surgery. Current and previous NSAID use was surveyed.
Cases were older than controls (70 vs. 64 years, p < 0.0001), and were more likely to have OA in the hips (45% vs. 21%, p < 0.0001), to have severe OA (p < 0.0001), and to be male (42% vs. 28%, p < 0.0008). Potential confounding variables were statistically adjusted using logistic regression. Although disease duration was similar in cases and controls (9.8 years), cases had tried fewer NSAIDs (1.3 +/- 0.05 vs. 2.3 +/- 0.08 in controls, p < 0.0001). Cases were less likely to have taken any NSAID (86% vs. 94% of controls; OR 0.40, p < 0.007) or to have had intra-articular steroids (OR 0.19, p < 0.0001). Two or more NSAIDs were used (ever) in 38% of cases vs. 70% of controls (p < 0.0001); and 3 or more NSAIDs in 5% vs. 38% (p < 0.0001). Women were less apt to have obtained total joint replacements (OR 0.62, p < 0.0001), including TKRs even when adjusting for severity of OA.
NSAIDs are used less by orthopedic surgeons than rheumatologists in our centre. Some subjects were offered a joint replacement without even a failure of medical management. The reasons for differences in prescribing trends are unknown. Referral biases may exist.