To evaluate the effect of infliximab on health related quality of life (HRQoL) and physical function in patients with active psoriatic arthritis (PsA) in the IMPACT 2 trial.
200 patients with PsA unresponsive to conventional treatment were randomised to intravenous infusions of infliximab 5 mg/kg or placebo at weeks 0, 2, 6, 14, and 22; patients with inadequate response entered early escape at week 16. HRQoL was assessed using the Short Form-36 (SF-36) at weeks 0, 14, and 24. Functional disability was assessed using the Health Assessment Questionnaire (HAQ) at every visit through week 24. Associations between changes in quality of life (SF-36) and articular (American College of Rheumatology (ACR)) and dermatological (Psoriasis Area and Severity Index (PASI)) responses were examined.
Mean percentage improvement from baseline in HAQ was 48.6% in the infliximab group compared with worsening of 18.4% in the placebo group at week 14 (p < 0.001). Furthermore, 58.6% and 19.4% of infliximab and placebo treated patients, respectively, achieved a clinically meaningful improvement in HAQ (that is, > or = 0.3 unit decrease) at week 14 (p < 0.001). Increases in physical and mental component summary (PCS and MCS) scores and all eight scales of the SF-36 in the infliximab group were greater than those in the placebo group at week 14 (p < or = 0.001). These benefits were sustained through week 24. Patients achieving ACR20 and PASI75 responses had the greatest improvements in PCS and MCS scores.
In patients with PsA, infliximab 5 mg/kg significantly improved HRQoL and physical function compared with placebo through 24 weeks.