Background Patients with SLE experience substantial health disparities. Studying the effect of spatial context on health outcomes has become a focus in health disparities research. The CDC Social Vulnerability Index (SVI) identifies communities where social determinants lead to higher levels of morbidity and mortality. We sought to understand the level of social vulnerability where patients with SLE reside and determine if specific dimensions of social vulnerability were associated with disease activity and prednisone utilization.

Methods 272 consented subjects who met either ACR or SLICC classification criteria for SLE were enrolled and longitudinally assessed from April 2014 to August 2020 (demographics in table 1). The census tract code was determined for the address listed for each patient’s index visit which corresponds to an SVI. Any tract with an SVI greater than the mean of 0.5 is defined as a socially vulnerable area. Prednisone dosing was organized into none, >0–7.5 mg, 8–20 mg, >20 mg. SLEDAI-2000 Responder Index-50 (S2K RI-50) assessed SLE disease activity (>4 indicated active SLE). A multinomial logistic regression model analysis was used to determine association.

Results There was no correlation between cumulative SVI and disease activity (OR 1.15, 95% CI=0.67–1.99). Compared to patients with invulnerable cumulative SVI, vulnerable patients were 2.31 times as likely to have higher dose of prednisone (1.36–3.92). Of the specific SVI dimensions, socioeconomic status (2.47, 1.43–4.27) and household composition (2.21, 1.28–3.83) associated with higher prednisone dose, whereas race/ethnicity/language (1.57, 0.92–2.68) and housing/transportation (1.08, 0.65–1.80) had no statistically significant association.

Conclusions Patients who live in more socially vulnerable areas are more likely to be prescribed higher doses of prednisone, specifically patients vulnerable in terms of socioeconomic status and household composition. This is worrisome as this likely will contribute to a higher burden of damage. These data highlight that access to social determinants is associated with health inequities.