Sex-Based Differences in Clinical Presentation, Management, and Outcomes of Acute Coronary Syndrome in Brazilian Emergency Medical Services
TL;DR
Within a private hospital network in Brazil, women with confirmed ACS were more often classified with less definitely ischemic chest pain and less frequently with STEMI or NSTEMI than men, which support sex-sensitive triage and diagnostic protocols to reduce inequities in ACS recognition and treatment.
Abstract
Background: Sex-related disparities in acute coronary syndrome (ACS) recognition and management remain a global health concern. We examined sex-based differences in clinical presentation, management, and outcomes among patients with chest pain attended by emergency medical services (EMS) across Brazil. Methods: We conducted a retrospective study using a registry from 14 Brazilian states between January 2020 and June 2024 within a private hospital network. Patients with chest pain were classified by cardiologists as unstable angina (UA), ST-elevation myocardial infarction (STEMI), or non-ST-elevation myocardial infarction (NSTEMI). Multivariable regression evaluated sex differences in diagnosis, treatment, and outcomes. Sensitivity analyses included state-clustered standard errors and E-values for unmeasured confounding. Results: Among 7,171 patients with confirmed ACS (68.2% male), median age was 63.0 years [IQR 20.0]; women were older than men (67.0 [20.0] vs 61.0 [19.0] years). Diagnoses were UA in 46.7%, STEMI in 18.8%, and NSTEMI in 34.6%. Overall, 91.7% received aspirin and 89.6% at least one additional antiplatelet agent. After adjustment, women had higher odds of chest pain classified as probably or possibly ischemic versus definitely ischemic (adjusted OR 1.51 [95% CI 1.33-1.72] and 1.60 [1.37-1.86], respectively) and lower odds of STEMI and NSTEMI relative to UA (adjusted OR 0.59 [0.51-0.68] and 0.74 [0.66-0.83], respectively). Door-to-ECG time was longer in women unadjusted ({beta}=1.53 minutes [0.24-2.82]) but not after adjustment ({beta}=1.04 [-0.27 to 2.36]). In-hospital mortality did not differ between sexes, with no evidence of excess short-term mortality in women. Conclusions: Within a private hospital network in Brazil, women with confirmed ACS were more often classified with less definitely ischemic chest pain and less frequently with STEMI or NSTEMI than men. Door-to-ECG differences did not persist after adjustment, and mortality did not differ by sex. These findings support sex-sensitive triage and diagnostic protocols to reduce inequities in ACS recognition and treatment.