Background/Purpose: Individuals with SLE can experience significant declines in functional status (FS). The ACR has recently identified physical function as a high-priority domain in SLE care. Socioeconomic status (SES) is a social determinant of health associated with adverse SLE-related health outcomes. Prior studies have shown an association between lower SES and poor FS in SLE, but this has not been studied at a national level. We evaluated the association between area deprivation index (ADI) as a proxy for SES and FS decline in a national SLE sample.

Methods: Data were derived from RISE, a national electronic health record-based registry. Individuals aged >18 with ≥ 2 visits for SLE ≥ 30 days apart and ≥ 2 FS scores documented from the physical functioning domains of the MDHAQ, HAQ, or HAQ II in 2016-2022 were included. Patients with a cancer history were excluded. For a given patient, FS scores used in the study were required to be ≥ 12 but no more than 24 months apart, to calculate the change in FS; FS decline was defined as a decrease in FS greater than the minimum clinically important difference for that functional status assessment measure (FSAM). ADI is a zip code-based measure of neighborhood poverty with the lowest quintile representing the highest area-level SES. We used a multi-level regression model to examine the association between ADI quintile and FS decline. We adjusted for age, sex, race and ethnicity, smoking status, Charlson comorbidity index (CCI), glucocorticoid (GC) use, csDMARD and bDMARD use all measured in the year prior to the first FS score; number of visits between the FS scores; and baseline FS score, accounting for clustering by practice. A secondary analysis included an interaction term for the association of ADI quintile and age. The linear trend of the predicted margins for FS decline across ADI quintiles was tested using a Wald test.

Results: We included 10,604 patients with a mean age of 54.8 ± 15.0 years; 91.3% were female and 60.5% were White (Table 1). The probability of FS decline was highest in the lowest SES group: FS decline occurred in 18.7% of patients in the lowest SES group vs. 12.5% of patients in the highest SES group (Figure 1 & Table 2; p for trend < 0.05). African American patients were slightly more likely to experience FS decline compared to White patients (18.9% vs.16.9%, respectively; p< 0.05). There was no evidence that the association between SES and FS decline was modified by age (P_interaction >0.05 for all FSAM outcomes).

Conclusion: In this large U.S. sample of adults with SLE, greater neighborhood deprivation was associated with higher likelihood of short-term FS decline, independent of individual sociodemographic and care utilization factors. Indeed, nearly 1 in 5 of individuals in the lowest-SES group experienced FS decline over a period of < 2 years. The widespread use of physical function patient-reported outcome quality measures, and interventions such as exercise programs, should be priorities in high-quality SLE care.

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ACR Meeting Abstracts - https://acrabstracts.org/abstract/socioeconomic-disparities-in-functional-status-by-neighborhood-deprivation-in-a-national-sample-of-patients-with-systemic-lupus-erythematosus/