Obesity is associated with premature occurrence of acute myocardial infarction

Background: The American Heart Association has classified obesity as a majo r modifiable risk factor for coronary artery disease, but its relationship with age at presentation with acute myocardial infarction (AMI) is poorly d ocumented. Hypothesis. The study was undertaken to evaluate the impact of obesity on a ge at presentation, and on in-hospital morbidity and mortality in patients with AMI. Methods: Our analysis includes a consecutive series of 906 Olmsted County p atients (mean age 67.7 years, 51 % male) admitted with AMI to the Mayo Clin ic Coronary Care Unit (CCU). The patients were entered into the Mayo CCU Da tabase, a prospective registry of data pertaining to patients admitted to t he Mayo Clinic CCU with AMI. Age at AMI occurrence and in-hospital morbidit y and mortality were noted. Results: Obese patients (body mass index [BMI] > 30) with AMI were signific antly younger than patients with AMI, in the overweight (BMI 25-30) and nor mal-weight (BMI < 30) groups (62.3 +/- 13.1 vs. 66.9 +/- 13.2 and 72.9 +/- 13.4, respectively, p < 0.001). Obesity and overweight status were associat ed with male gender, diabetes mellitus. hypercholesterolemia, and smoking h istory; however, after multivariate adjustment for these risk factors, exce ss weight and premature AMI remained significantly associated. Compared wit h normal-weight patients, overweight patients presenting with AMI were 3.6 years younger (P < 0.00 1, confidence interval [CI] 1.9-5.4) and obese pati ents 8.2 years younger (p < 0.001, CI 62-10.1). No significant increase in in-hospital morbidity and mortality was seen. Conclusion: In this population-based study, overweight and obese status are independently associated with the premature occurrence of AMI, but not wit h an increased incidence of inhospital complications.