Patient-perceived flares in rheumatoid arthritis: A sub-analysis of the STRASS treatment tapering strategy trial

International audienceObjectives: Patient's and physician's perspective can differ in rheumatoid arthritis (RA). The aim was to define the concept of patient-reported flares.Methods: Post-hoc analysis of a randomized controlled trial of a step-down strategy in RA patients treated with anti-TNF, in DAS28-remission for >= 6 months, randomized to either "spacing" or "maintaining" anti-TNF. The occurrence of patient-reported flares (PRF) was evaluated every 3 months for 18 months by: "Over the last 3 months, did you experience symptoms suggestive of disease exacerbation?". Visits with and without PRF were compared, using a linear mixed effects model, in terms of symptoms, disability based on the Health Assessment Questionnaire, quality of life based on Short Form 36 Health Survey and DAS28 based relapses (DBR), defined as an increase of DAS28 > 0.6 and an absolute value of DAS28 > 2.6. The agreement between PRF and DBR was measured by the kappa coefficient on repeated data.Results: In all, 137 patients were analyzed: mean age 55 +/- 11 years, females 78%, mean RA duration 9.5 +/- 8.0 years. Over the 18 months, PRF concerned 27.2% of the 940 available visits. DBR and PRF were observed in 24% and 16% of 940 visits for 137 patients respectively. All the items were associated with PRF with standardized effect size between -0.58 (SF36 PCS) and 0.87 (DAS28). The agreement between PRF and DBR was moderate (kappa = 0.44).Conclusion: The concept of flare refers to more than just RA disease activity