Objective To test the longitudinal association between patient-reported outcome, Routine Assessment of Patient Index Data 3 (RAPID3) and the Disease Activity Score in 28 joints that includes the erythrocyte sedimentation rate (DAS28-ESR) in routine-care patients with rheumatoid arthritis (RA).
Methods Patients with RA treated with disease-modifying antirheumatic drugs were included in this prospective observational cohort. The longitudinal association between RAPID3 (0–10) and DAS28-ESR and its individual components (swollen joint count (SJC), erythrocyte sedimentation rate (ESR) (mm/hour), tender joint count (TJC) and patient global assessment (PGA)) was tested using generalised estimating equations in patients with more than two consecutive visits with data on RAPID3 and DAS28-ESR. Interactions between RAPID3 and gender, pain, PGA and age at baseline were tested, and if significant (p<0.20) and clinically relevant, models were fit in the corresponding strata.
Results In total, 330 patients were included (mean follow-up 10.7 (SD 9.7) months, female gender 67.9%). The longitudinal association between RAPID3 and DAS28-ESR was weak (β=0.29 (95% CI 0.24 to 0.35), n=207), meaning that one unit increase in RAPID3 corresponded to a 0.29 unit increase in Disease Activity Score in 28 joints (DAS28). RAPID3 was most strongly associated with subjective (TJC: β=0.89 (95% CI 0.61 to 1.17); PGA: β=0.94 (95% CI 0.84 to 1.04)) and not with objective components of DAS28 (SJC: β=0.29 (95% CI 0.17 to 0.41), n=172). The association between RAPID3 and ESR was poor but modified by gender, being only significant in men (β=0.37 (95% CI 0.08 to 0.67)).
Conclusions These data suggest that RAPID3 does not sufficiently capture changes in objective inflammatory signs. Monitoring by RAPID3 alone is therefore insufficient to follow disease activity in patients wth RA in clinical practice.
- Rheumatoid arthritis
- disease activity
- patient reported outcome measure (PROM)
This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See: https://creativecommons.org/licenses/by/4.0/.
Statistics from Altmetric.com
Contributors NWB, AS and RL had full access to all of the data and take responsibility for data integrity and accuracy of data analysis. NWB, AS and RL were involved in the data processing and analysis. NWB, AS, RL, P-HvdK RJ and RP were involved in the study design and writing of the manuscript. All authors contributed to the critical revision and the final approval of the manuscript.
Funding There was no funding for this study. AS is supported by a doctoral grant from Fundação para a Ciência e Tecnologia (Foundation for Science and Technology) (SFRH/BD/108246/2015).
Competing interests None.
Patient consent for publication Not required.
Ethics approval The local medical ethics committee reviewed the study and approved the protocol.
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement No additional data are available for sharing.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.