Association of Social Determinants of Health and Penicillin Allergy Labels: A Case-Control Study

Penicillin allergy labels (PALs) are associated with numerous adverse outcomes, including poor infectious outcomes and antimicrobial resistance. Studies assessing the association of social vulnerability (SV) characterized by social determinants of health (SDoH) factors and PAL epidemiology are lacking.

This retrospective case-control study included patients encountering a US academic medical center in 2014-2023. Cases were defined as patients with PALs; controls were defined as patients without PALs and with a penicillin medication order. The primary independent variable was SV defined by the Community Vulnerability Compass, including 20 indicators of SV. The primary outcome was PAL documentation. Bivariate analyses were performed to examine the association among SV, covariates, and PALs.

32 952 PAL cases and 171 189 controls were included (mean [SD] age: 36.3 [21.4] years; 107 498 [52.7%] Hispanic; 4566 [2.2%] non-Hispanic Asian; 55 422 [27.1%] non-Hispanic Black; 31 680 [15.5%] non-Hispanic White). An inverse relationship between SV and PALs was observed. The highest SV quintile was associated with decreased PALs (unadjusted OR: .52; 95% CI: .50-.54). Adjusting for SV, non-Hispanic White identification was significantly associated with PALs, with significantly decreased PALs observed in other groups: Hispanic (adjusted OR [aOR]: .38; 95% CI: .36-.41), non-Hispanic Black (aOR: .45; 95% CI: .42-.48), non-Hispanic Asian (aOR: .40; 95% CI: .34-.45).

A significant inverse relationship between SV and PALs was observed, with lower SV associated with increased PALs. Significant racial disparities in PALs persisted despite adjusting for SDoH, suggesting that racially and ethnically identified groups interact differently within the healthcare system with regard to acquiring PALs.