Variations in coronary procedure utilization depending on body mass index.

BACKGROUND: Increased body mass index (BMI) (calculated as weight in kilograms divided by the square of height in meters) is a risk factor for coronary heart disease and is associated with lower preventive services utilization. The relationship between BMI and utilization of diagnostic or therapeutic procedures for coronary heart disease has not been examined.
METHODS: We evaluated 109 664 Medicare patients who were hospitalized for acute myocardial infarction in a nongovernmental acute care hospital between 1994 and 1996, were 65 years or older, and weighed 159 kg or less. We used logistic regression to examine the relationship of BMI with utilization of cardiac catheterization, percutaneous coronary intervention, and coronary artery bypass grafting while adjusting for patient and hospital characteristics.
RESULTS: Participants had a mean age of 75.8 years; 53% were men and 90% were white. Individuals with a BMI of 25.0 to 35.0 had the highest rates of coronary procedure utilization. Compared with patients with a BMI of 25.0 to 29.9, those with a BMI of 35.0 to 39.9 had a reduced adjusted odds ratio (OR) of receiving coronary artery bypass grafting (OR, 0.88; 95% confidence interval [CI], 0.79-0.98), whereas patients with a BMI of 40.0 or greater had the lowest odds of receiving cardiac catheterization (OR, 0.82; 95% CI, 0.73-0.92), percutaneous coronary intervention (OR, 0.89; 95% CI, 0.77-1.03), and coronary artery bypass grafting (OR, 0.68; 95% CI, 0.57-0.82). Patients who did not receive coronary revascularization had higher mortality rates than those who did.
CONCLUSIONS: For patients hospitalized with acute myocardial infarction, those with a very high BMI were less likely to receive invasive coronary procedures. Future research should investigate reasons for these variations in coronary procedure utilization.