During the course of rheumatoid arthritis (RA), patients have profound negative effects on their patient-reported-outcomes (PRO); in addition, the impact of sustained remission (SR) on PROs may differ for each particular outcome. The objectives of this study were to identify SR from an inception cohort of RA patients and to examine the impact of SR in an ample spectrum of PROs.
The study was developed in a well characterized and ongoing cohort of RA patients with recent onset disease recruited from 2004 onwards. In November 2016, the cohort included 187 patients, of whom 145 had at least 30 months of follow-up, with complete rheumatic assessments at regular intervals in addition to a pain visual analogue scale (PVAS), overall disease-VAS (OVAS), health assessment questionnaire (HAQ), Short-Form 36v2 Survey (SF-36) and fatigue assessment. First SR was defined according to the DAS28 cut-offs (DAS28-SR) and ACR/EULAR 2011 Boolean definition (B-SR), if maintained for at least 12 consecutive months. The dependent t test and Mc Nemar's tests were used for comparisons between related groups. Local IRB approval was obtained.
More patients achieved DAS28-SR than B-SR: 78 vs. 63, respectively. Fifty patients met both SR definitions. Follow-up to DAS28-SR was shorter than to B-SR and the duration of DAS28-SR was longer, p ≤ 0.023 for all comparisons. At SR, patients had PRO proxy to normal values; the percentage of patients with normal PRO varied from 97% (95% CI: 91-99) for HAQ to 50% (95% CI: 39-61) for absence of fatigue. In DAS28-SR patients, acute reactant phases within the normal range were detected very early (after 1.5-2.9 months). HAQ, PVAS, OVAS and SF-36 were scored within the normal range after 6-7 months. The absence of fatigue was detected at 8.7 months of follow-up, which was similar to DAS28-SR. In the 63 patients with B-SR, a similar pattern was observed. The follow-up to outcomes of the 50 patients who met both SR definitions was similar, but the absence of fatigue and physical component SF-36 normalization were achieved earlier in B-SR patients (p ≤ 0.02).
The impact of SR on PRO differs accordingly to each particular outcome.