Little is known about the impact of changes in body mass index (BMI) after the percutaneous coronary intervention (PCI) on long-term outcomes in patients with coronary artery disease (CAD). Therefore, this study aimed to clarify this issue. We investigated data on CAD obtained from the SHINANO Registry, a prospective, observational, multicenter cohort study, from 2012 to 2013 in Nagano, Japan. One year after PCI, the enrolled patients were divided into the following three groups based on changes in BMI by tertiles: reduced, maintained, and elevated BMI. The associations among the groups and the 4-year outcomes [major adverse cardiac events (MACEs), all-cause death, Q-wave myocardial infarction, and stroke] were examined.
Five hundred seventy-two patients were divided into the reduced, maintained, and elevated BMI groups. Over the 4-year follow-up period, the cumulative incidence of MACEs was 10.5% (60 cases). In the Kaplan-Meier analysis, the incidence rates of MACE were significantly higher in the reduced BMI group than in the maintained and elevated BMI groups [17.7% versus (vs.) 7.3% vs. 9.0%, p = 0.004]. Multivariable cox regression analysis showed that the reduced group showed increased risks of MACEs (hazard ratio 2.15; 95% confidence interval 1.29-3.57; p = 0.003). The long-term clinical outcomes of patients with CAD who underwent PCI were affected by the reduction in BMI after PCI. Furthermore, the elevation of BMI after PCI was not a poor prognostic factor.