Background/Purpose: Patient assessment of disease activity (PtGA) measured by visual analog scale (VAS) is often a barrier to patients achieving remission in rheumatoid arthritis (RA). The Boolean and Simplified Disease Activity Index (SDAI) criteria for remission mandate a PtGA of ≤10mm and ≤33mm, respectively. For this reason, it is critical to understand the patient perspective on model disease states, including remission. The objective of our study was to determine how a diverse cohort of RA patients interprets case scenarios of disease states, and to identify variables that were associated with rating the remission model disease state at ≤10mm and ≤33mm.

Methods: We enrolled English- and Spanish-speaking patients at our clinic who met American College of Rheumatology 2010 criteria for RA. We asked subjects to rate their health on a VAS if their arthritis were like that described in each of four case scenarios ranging from remission to severe RA disease activity. These scenarios included the domains: engagement in activities of daily living; personal care; anxiety related to the course of disease; leisure activity; pain; and side effects of treatment. Responses were classified according to Figure 1.  We performed multivariate logistic regression to identify predictors of: 1) scorable responses with the remission disease state rated lower than the severe disease state (category 4 [Cat 4]); 2) rating the remission model disease state ≤10mm; or ≤33mm.  

Results: We enrolled 300 subjects.  Only 128 subjects were grouped into Cat 4, indicating understanding of the scenarios.  By multivariate regression, higher health literacy (HL) (OR 1.20) and increasing education (OR 2.02) were associated with being grouped in Cat 4. The mean score for the remission scenario for Cat 4 was 17 mm. Of the Cat 4 subjects, 70% and 79% assigned the remission model scenario a score that would satisfy the Boolean and SDAI remission criteria, respectively. No socio-demographic variable predicted responses ≤10mm. Increasing income (OR 5.37) and decreasing pain scores (OR 0.79) predicted classification of the remission model scenario at a level of ≤33mm (Table 1).

Conclusion: Limited HL and education are associated with responses to the remission scenario that are inconsistent with understanding the VAS line or question content. Approximately 30% of the patients in Cat 4 rated the remission model disease state at a level that would preclude them from being judged in remission by the Boolean criteria. These results expand what is known about patient perspectives of remission and the challenges of meeting remission criteria in clinics caring for diverse and disadvantaged populations.