Inverted U-shaped relationship between body mass index and multivessel lesions in Chinese patients with myocardial infarction: a cross-sectional study

Objective: To investigate the association of body mass index (BMI) with multivessel coronary artery disease in patients with myocardial infarction.

Methods: This study was performed in 1566 patients with myocardial infarction in the Department of Cardiology, Affiliated Hospital of Jining Medical University, China. Independent and dependent variables were BMI measured at baseline and multivessel coronary artery disease, respectively. The covariates examined in this study were age, systolic blood pressure, diastolic blood pressure, heart rate, creatinine, uric acid, bilirubin, cholesterol, triacylglycerol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, left ventricular ejection fraction, sex, heart failure, atrial fibrillation, chronic obstructive pulmonary disease, stroke, hypertension, diabetes mellitus, and smoking.

Results: A nonlinear relationship was detected between BMI and multivessel coronary artery disease, and this was an inverted U-shaped curve and the cutoff point was 26.3 kg/m². The effect sizes and confidence intervals on the left and right sides of the inflection point were 1.10 (1.01-1.20) and 0.85 (0.74-0.97), respectively.

Conclusions: There is an obesity paradox for BMI > 26.3 kg/m². Future studies should examine the relationship between BMI and prognosis in patients with myocardial infarction, which may be important for improving the prognosis through control of BMI.

Keywords: Body mass index; coronary artery disease; inverted U-shaped curve; multivessel lesion; myocardial infarction; obesity paradox.