Patients with rheumatoid arthritis (RA) who are living in areas with disadvantageous socioeconomic status (SES) appear to have higher disease activity, disability, and poorer quality of life (QOL), as shown in a study in Australia.
“Our results suggest an inequity in health outcomes for patients with RA despite treat-to-target management within a universal healthcare system,” the researchers said.
A total of 255 adult patients with RA (mean age 53.9 years, 66.7 percent female) diagnosed after June 2003 were analysed. Of these, 68 percent had seropositive disease. [J Rheumatol 2026;53:501-509]
An ordered trend was observed across SES quintiles, with higher quintiles correlating with lower Disease Activity Score in 28 joints based on C-reactive Protein (DAS28-CRP; p=0.03), lower modified Health Assessment Questionnaire (mHAQ; p=0.001), and higher 36-item Short Form Health Survey physical component summary (SF-36 PCS; p<0.001).
On the other hand, SES quintile showed no significant association with biologic/targeted synthetic disease-modifying antirheumatic drug (b/tsDMARD) initiation or switching.
“Greater comorbidity was independently associated with poorer RA outcomes and greater b/tsDMARD use, and this may be a clue to understanding the unexplained gap in outcomes associated with SES,” the researchers said.
A previous study suggests that greater comorbidity is associated with more complex patient care, especially in those with lower SES, potentially leading to higher burden of treatment (eg, escalation of RA-directed immunosuppression in response to greater perceived disease activity). [J Clin Epidemiol 2012;65:1041-1051]
“This is an emerging area of research in RA and may enable better understanding of currently unexplained gaps in patient outcomes,” the researchers said. “Future qualitative research would likely contribute to better understanding of the interplay of these issues.”
Mechanisms
It remains unclear how SES may contribute to poorer health outcomes in RA patients.
Potential explanations for the relationship between low SES and poorer RA outcomes included the following: obesity, effects of smoking, greater allostatic load, early adverse childhood experiences, and differences in medication use. [Arthritis Care Res 2017;69:157-165; N Engl J Med 1998;338:171-179; Pain 2009;143:76-83; Arthritis Care Res 2022;75:92-100]
“Our results highlight the importance of socioeconomic factors in individuals with early RA,” the researchers said. “As RA-specific medications appear to be appropriately used, nonpharmacological interventions may be considered to begin addressing this gap, such as healthcare navigation and improving access to allied health services.”
Furthermore, the effect of comorbidities must be addressed, taking into consideration the ageing population with an increasing burden of treatment complexity.
“Ultimately, although addressing the upstream structural social determinants of health remains central in aiming to reduce healthcare inequities, healthcare providers’ continued advocacy at both the individual and community levels remains vital in confronting these challenges,” the researchers said.
In the current study, SES was defined as quintiles of Index of Relative Social Advantage and Disadvantage based on residential address at baseline. Covariates assessed were as follows: baseline age, sex, BMI, smoking status, and the Rheumatic Disease Comorbidity Index.
The researchers used longitudinal multivariable random effects regression models with restricted cubic splines examining nonlinear responses in outcome variables. They also assessed the use of b/tsDMARD via time-to-event models for recurrent events.