A Stratified Analysis of the Risk Associated With Low Body Mass Index for Patients After Percutaneous Coronary Intervention

Aims: The relationship between low body mass index (BMI) and prognostic factors for patients with coronary artery disease, commonly observed in elderly individuals in Japan, is important. Few studies have evaluated the prognosis for patients with low BMI after percutaneous coronary intervention (PCI). Using a multivariable-adjusted model and data from a prospective cohort registry, we analyzed the risk associated with low BMI for patients after PCI. Methods: This prospective, multicenter registry included 5965 consecutive patients with coronary artery disease who underwent successful PCI. The patients were followed-up clinically for up to 3 years or until the occurrence of major adverse cardiac events. The primary endpoint was all-cause death and nonfatal myocardial infarction composite. Results: Primary events occurred in 639 (10.7%) patients during the follow-up period. A risk analysis of the primary endpoint adjusted for the multivariable model showed a significant increase in risk for elderly individuals, underweight individuals [HR 1.43 (95% confidence interval (CI), 1.10–1.85),P＜0.001], those with diabetes mellitus (DM), peripheral artery disease, low left ventricular ejection fraction or acute coronary syndrome (ACS), and smokers. A stratified adjusted risk analysis based on BMI levels showed that the risk associated with underweight status was significantly pronounced for male patients, those aged 60–74 years, and those with DM or ACS. Conclusion: Underweight patients with several risk factors significantly increased risk after PCI. Furthermore, the risk associated with low BMI was significantly more pronounced for men, individuals aged 60–74 years, and patients with DM or ACS.