Acute coronary syndromes presentations and care outcomes in white, South Asian and Chinese patients: a cohort study

OBJECTIVES: Successful treatment of acute coronary syndrome (ACS) relies on its rapid recognition. It is unclear whether the accepted presentation of chest pain applies to different ethnic groups. We thus examined potential ethnic variations in ACS symptoms and clinical care outcomes in white, South Asian and Chinese patients. DESIGN: Cross-sectional survey. SETTING: Participants were hospitalised at 1 of 12 Canadian centres across four provinces. PARTICIPANTS: 1334 patients with ACS (630 white; 488 South Asian; 216 Chinese). MAIN OUTCOME MEASURES: ACS presentation symptoms (classic/typical midsternal pain/discomfort with or without radiation to the left neck, shoulder or arm) were assessed by self-report. Clinical care outcomes (time to emergency room [ER] presentation, cardiac catheterisation; receipt of cardiac catheterisation, percutaneous coronary intervention [PCI] or coronary artery bypass grafting [CABG]) were obtained by health record audit. RESULTS: The mean age of the sample was 62 years and 30% had ST-elevation myocardial infarction (STEMI). The most common presenting symptom was midsternal pain/discomfort of any intensity regardless of ethnic status. Yet, a substantial proportion of patients reported atypical symptoms (33% white, 19% South Asian, 20% Chinese; p<0.006). After adjustment for age, sex, education, current smoking, extent of coronary artery disease, presence of diabetes or chronic kidney disease and STEMI vs non-STEMI/unstable angina, South Asians were more likely to present with at least moderate intensity midsternal pain/discomfort (adjusted OR [AOR] 1.44; 95% CI 1.05 to 1.98), whereas Chinese were less likely to present with radiating symptoms (AOR 0.53; 95% CI 0.38 to 0.74) compared with whites. South Asians with atypical pain (relative to those with midsternal pain/discomfort) took significantly longer to present to the ER (p=0.037), and were less likely to receive PCI (p=0.008) or CABG (p=0.041). CONCLUSIONS: Atypical presentations were associated with greater delays in arrival to the emergency department and reduced invasive cardiovascular care in South Asians.