Racial and sex differences in acute pericarditis among emergency department chest pain patients: a retrospective cohort study

Acute pericarditis is a rare diagnosis among emergency department (ED) patients with chest pain, and how race and sex jointly influence risk remains poorly characterized. We evaluated race–sex heterogeneity in acute pericarditis risk using interaction-based and marginal analytic approaches. This retrospective cohort study utilized patient-level electronic health records from 10 EDs in a large integrated health system (2016–2022). Adult patients (≥ 18 years) self-identifying as non-Hispanic Black or non-Hispanic White and presenting with chest pain were included. Acute pericarditis was identified using International Classification of Diseases, Tenth Revision codes I30.x, supported by clinical documentation. Generalized linear models with log link and robust variance estimated risk ratios (RRs) for race, sex, and their interaction. Because interaction models yield conditional coefficients, inference focused on race–sex contrasts and on marginal predicted probabilities derived from recycled prediction methods. Among 114,517 ED chest pain visits, 346 (0.30%) met criteria for acute pericarditis, including n = 151 non-Hispanic Black patients and n = 195 non-Hispanic White patients. Evidence of race–sex effect modification was observed. Compared with non-Hispanic White women, non-Hispanic Black men had a statistically significantly higher adjusted risk of acute pericarditis (RR = 1.72; 95% CI, 1.10–2.69). Marginal estimates indicated higher adjusted predicted risk among men across both racial groups, with the highest absolute and relative risks among non-Hispanic Black men. Results from sensitivity analyses excluding the COVID-19 period were similar. Despite the rarity of the disease, acute pericarditis has clinically significant heterogeneity among race–sex subgroups. Marginal estimates based on interaction suggest that non-Hispanic Black men have the highest risk, suggesting the utility of intersectional demographic analysis in ED chest pain triage.