Abstract
Objective Systemic Lupus Erythematosus (SLE) disproportionately affects racial and ethnic minority populations in the US. Though discrimination is linked to worse SLE outcomes, the mechanisms of this association remain underexplored. Among a multiracial, multiethnic cohort with SLE, we explored relationships between discrimination and patient-reported outcomes (PROs) and if mental health affects these relationships.
Methods We analyzed data from the California Lupus Epidemiology Study, comprised of Asian (31%), Black (10%), Hispanic (24%), and White (34%) participants (N=245). Participants completed the Everyday Discrimination Scale and the following PROs: Systemic Lupus Activity Questionnaire (SLAQ), PROMIS Pain Interference and Fatigue, PHQ8 (depression), and GAD7 (anxiety). Multivariable linear regressions modeled associations between discrimination and PROs. Mediation analyses evaluated if depression or anxiety mediated associations between discrimination and SLAQ, pain, or fatigue.
Results Everyday discrimination scores were highest among Black and Asian participants. Among multivariable models, higher discrimination was associated with worse SLAQ (β=0.25, P < 0.001), PHQ8 (β=0.21, P < 0.001), GAD7 (β=0.27, P < 0.001), pain (β=0.24, P=0.01), and fatigue (β=0.3, P=0.007). By racial/ethnic subgroups, discrimination was significantly associated with higher SLAQ among Black and Asian participants. Discrimination was no longer significantly associated with SLAQ, pain, or fatigue after adjusting for PHQ8 or GAD7.
Conclusion In this diverse SLE cohort, discrimination was associated with greater patient-reported disease activity, pain, fatigue, depression, and anxiety. Mediation analyses suggest that mental health mediates the relationship between discrimination and PROs. These results highlight the impact of discrimination as a psychosocial stressor on disease outcome variables.
