EFFECTS OF ANTIINFLAMMATORY DRUGS ON THE PROGRESSION OF OSTEOARTHRITIS OF THE KNEE

Objective. To compare the rate of radiographic progression in knee ost eoarthritis (OA) comparing indomethacin with placebo and tiaprofenic a cid with placebo. Methods. Rate of radiographic progression of OA of t he knees was studied in 812 patients in a randomized double blind para llel group study at 20 rheumatology clinics in the United Kingdom and analyzed sequentially. Patients received either indomethacin 25 mg thr ee times daily, tiaprofenic acid 300 mg twice daily, or matched placeb o. All had access to paracetamol as a rescue analgesic. Joint space na rrowing was measured by a 6 point grading scale, using radiographs tak en with a standardized technique at recruitment and annually thereafte r. Results. Three hundred and seventy six patients completed at least one year of study medication and therefore contributed evaluable resul ts. More than twice as many patients showed deterioration in the indom ethacin group as in the placebo group; of 170 available patients at th e 3rd interim analysis, 40 of 85 receiving indomethacin had deteriorat ed compared to 19 of 85 receiving placebo, a statistically significant difference (p = 0.009). No statistically significant difference (p = 0.308) was found between tiaprofenic acid and placebo at the 7th inter im analysis, the conclusion of the study. Conclusion. Indomethacin inc reased the rate of radiological deterioration of joint space in patien ts with OA of the knee; tiaprofenic acid did not.