Obesity, Treatment Times, and Cardiovascular Outcomes After ST-Elevation Myocardial Infarction: Findings From Mission: Lifeline North Texas

BACKGROUND: With increasing rates of obesity and its link with cardiovascular disease, there is a need for better understanding of the obesity-outcome relationship. This study explores the association between categories of obesity with treatment times and mortality for patients experiencing ST-segment elevation myocardial infarction.

METHODS AND RESULTS: We examined 8725 patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention and used regression models to analyze the relationship between 6 categories of body mass index with key door-to-balloon time, total ischemic time, and in-hospital mortality. We relied on data from the Mission: Lifeline North Texas program, consisting of 33 percutaneous coronary intervention-capable hospitals in 6 counties surrounding Dallas, Texas. Data were extracted from the National Cardiovascular Data Registry for each participating hospital. Of the samples, 76% were overweight or obese. Comparing the univariate differences between the normal-weight group and the pooled sample, we observed a U-shaped association between body mass index and both mortality and door-to-balloon times. The most underweight and severely obese had the highest mortality and median door-to-balloon time, respectively. These differences persisted after multivariate adjustments for door-to-balloon time, but not for mortality.

CONCLUSIONS: Extremely obese patients have longer treatment time delays than other body mass index categories. However, this did not extend to significant differences in mortality in the multivariate models. We conclude that clinicians should incorporate body mass assessments into their diagnosis and treatment plans to mitigate observed disparities.