Objective: To assess the tolerability of sulfasalazine in a clinic setting and determine its longterm effectiveness with respect to articular disease and prevention of radiographic progression in patients with psoriatic arthritis (PsA).
Methods: Patients who were given sulfasalazine during their attendance at the University of Toronto Psoriatic Arthritis Clinic were enrolled in the study. For patients that were able to tolerate sulfasalazine for at least 3 months a matched control was identified who did not receive sulfasalazine. The primary outcome measures were the tolerability of sulfasalazine, clinical response of the actively inflamed joints at 6 and 12 months, and the change in radiographic score at 24 months.
Results: Thirty-six patients received sulfasalazine. Fourteen of 16 patients discontinued sulfasalazine due to one or more side effects occurring within 3 months of treatment initiation. For the remaining 20 patients, a 50% reduction in actively inflamed joint count was noted in 7/20 patients at 6 months and 11/15 patients at 12 months, compared to 7/19 patients in the control group at 6 months and 10/20 patients at 12 months. The mean change in the radiographic score at 24 months between the 2 groups was not statistically significant.
Conclusion: Sulfasalazine was not well tolerated in patients with PsA in our clinic. For those able to tolerate sulfasalazine, there was no evidence of a treatment effect with respect to articular involvement. In addition, sulfasalazine does not appear to halt radiographic progression in PsA.