Understanding Heterogeneity in Patients' Conceptualisation of Treatment for Rheumatoid Arthritis: A Cluster Analysis

Uptake of treat-to-target (TTT) strategies for rheumatoid arthritis (RA) management is low. Our objective was to understand the heterogeneity in patients' conceptualisation of RA treatment to inform interventions improving TTT uptake.

Eligible participants recruited from an online research registry rated 56 items (on 5-point scales) reflecting concepts raised from patient interviews. Using items describing adhering to physician recommendations to create a binary criterion variable for medication adherence, we conducted a principal components analysis on the remaining items using Varimax rotation, describing how these factors predict adherence over and above demographic characteristics. We further use optimal sets in regression to identify the individual concepts that are most predictive of medication adherence.

We found significant heterogeneity in patients' conceptualisation of RA treatment among 621 persons with RA. A scree plot revealed a four-factor solution explained 38.4% of the variance. The four factors expected to facilitate TTT uptake were (% variance explained): (1) Access to high quality care and support (11.3%); (2) low decisional conflict related to changing disease-modifying antirheumatic drugs (DMARDs) (10.1%); (3) endorsement of a favourable DMARD risk/benefit ratio (9.9%); and (4) confidence that testing reflects disease activity (7.2%). These factors account for 13.8% of the variance in full medication adherence, fully explaining the only significant demographic predictor, age of the patient. The individual items most predictive of poor adherence centre on the lack of effective patient-physician communication, specifically insufficient access to information from rheumatologists, along with the need to seek information elsewhere.

Patients' conceptualisation of RA treatment varies; however, almost all patients have difficulty escalating DMARDs, even with access to quality information and an understanding of the benefits of TTT. Tailored interventions are needed to address patient hesitancy to escalate DMARDs.