Longterm therapy of psoriatic arthritis: Intramuscular gold or methotrexate?

Objective. To compare the efficacy and toxicity of methotrexate (MTX) and i ntramuscular (im) gold in the treatment of psoriatic arthritis (PsA). Methods. Medical records from all patients with PsA attending the gold and MTX clinics at the Vancouver Mary Pack Arthritis Centre between 1971 and 19 95 were reviewed. The odds of a clinical response (defined as at least a 50 % reduction in active joint count From initial to last visit or for at leas t 6 months) and the relative risk of discontinuing therapy associated with treatment (MTX or im Sold) were calculated after controlling for significan t baseline covariates, using logistic regression and Cox regression analyse s, respectively. The frequency of side effects and the reasons for treatmen t cessation were also compared between treatment groups. Results. Eighty-seven patients received ill treatment courses: 43 of MTX an d 68 of im gold, The likelihood of a clinical response was 8.9 times greate r (95% CI 1.8, 44.0) with MTX than im gold, patients were 5 times more like ly (95% CI 2.4; 10.4) to discontinue therapy with im gold than with MTX;. N o major toxicity occurred and frequency of side effects was similar for bot h treatments. Patients with a longer duration of PsA prior to initiation of study treatment were less likely to achieve a clinical response. Conclusion. MTX and im gold are safe and well tolerated in the treatment of PsA, In our experience, MTX was superior to im gold in the likelihood of a chieving a clinical response and in permitting an individual to continue lo ngterm treatment. Our data suggest that earlier treatment may be associated with a better response.