Patient-reported outcomes better discriminate active treatment from placebo in randomized controlled trials in rheumatoid arthritis

BACKGROUND: Recent randomized controlled trials (RCTs) in rheumatoid arthritis (RA) have used patient- and physician-reported outcomes, ESR and/or CRP as components of ACR response criteria to assess efficacy. OBJECTIVES: Mean changes from baseline in patient- and physician-reported outcome measures, ESR and CRP were compared in two RCTs in patients with active RA. Comparisons between active and placebo treatment used mean percentage improvements and standard effect sizes (SESs). RESULTS: In both protocols, patient-reported assessments of disease activity, pain and physical function reflected little or no improvement with placebo, best discriminating between active and placebo therapy, as did ESR and CRP. CONCLUSION: Improvements in signs and symptoms of active RA in placebo RCTs appear to be best reflected by patient-reported measures of physical function, as long as reported changes in global assessments of disease activity and/or pain reflect similar benefit. Patient-reported outcome measures should be considered objective; treatment-associated changes are congruent with measures of inflammation, and appear less susceptible to the placebo response.