Relationship between body mass index and prognosis of patients presenting with potential acute coronary syndromes

Objectives Studies examining the relationship between obesity and acute coronary syndrome (ACS) have been limited to patients with confirmed diagnoses. The authors sought to determine the relationship between body mass index (BMI) and 30-day cardiovascular events in emergency department (ED) patients with potential ACS. Methods This was a secondary analysis of a prospective cohort study of patients who presented to the ED with potential ACS. Patients were stratified according to their BMI: underweight (BMI < 18.49 kg/m ²), normal weight (BMI = 18.5 to 24.99 kg/m²), overweight (BMI = 25 to 29.99 kg/m²), obese (BMI = 30 to 34.99 kg/m ²), and very obese (BMI > 35 kg/m²). The primary outcome was acute myocardial infarction (AMI), death, or revascularization within 30 days of presentation. A logistic regression analysis was used to adjust for confounding variables and adjusted odds ratios (aOR) with 95% confidence intervals (CIs) are presented for cardiac events and readmission outcomes. Results Of the 3,946 patients included in this study, 73 (1.9%) were underweight, 911 (23%) were normal weight, 1,199 (30.4%) were overweight, 872 (22.1%) were obese, and 891 (22.6%) were very obese. Although increased levels of obesity were associated with a greater number of cardiac risk factors, there was no difference in 30-day cardiovascular events between those of normal weight and underweight (aOR = 1.1; 95% CI = 0.4 to 2.7), overweight (aOR = 1.0; 95% CI = 0.7 to 1.4), obese (aOR = 1.2; 95% CI = 0.8 to1.7), or very obese (aOR = 0.8; 95% CI = 0.5 to 1.3). Those who were underweight were more likely to be readmitted within 30 days (aOR = 1.9; 95% CI = 1.0 to 3.7), and those who were very obese were less likely to be readmitted within 30 days (aOR = 0.7; 95% CI = 0.5 to 0.9). Conclusions Among patients who present to the ED with potential ACS, BMI is not associated with higher risk of cardiovascular outcomes at 30 days.