Association between body mass index and clinical outcomes after new-generation drug-eluting stent implantation: Korean multi-center registry data

Background and aims: It is unclear whether the obesity paradox is still apparent in the new-generation drug-eluting stent (DES) era. Therefore, we assessed the impact of body mass index (BMI) on clinical outcome after percutaneous coronary intervention (PCI) with new-generation DESs. Methods: A total of 5264 consecutive patients from 4 new-generation DES registries were divided into 4 categories according to BMI: 1) underweight (BMI<18.5 kg/m², n = 130), 2) normal weight (18.5 ≤ BMI <25 kg/m², n = 2943), 3) overweight (25 ≤ BMI<30 kg/m², n = 1932), and 4) obese (BMI≥30 kg/m², n = 259). The primary endpoint was the occurrence of major adverse cardiac and cerebrovascular event (MACCE) at 12 months, including all-cause mortality, nonfatal myocardial infarction, stroke, and target-vessel revascularization. Results: The 12-month MACCE rates decreased according to increasing BMI categories. (underweight, 13.1%; normal, 6.0%; overweight, 4.8%; obese, 4.2%; p < 0.001). After adjustment for other confounders, the underweight group had significantly higher MACCE rates than the normal-weight (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.33–0.99; p = 0.049), overweight (HR, 0.49; 95% CI, 0.27–0.88; p = 0.017), and obese (HR, 0.41; 95% CI, 0.18–0.98; p = 0.044) groups. These differences were mainly driven by all-cause mortality and target-vessel revascularization. When BMI was treated as a continuous variable, BMI per 1 kg/m² was also an independent predictor for MACCE (HR, 0.95; 95% CI, 0.91–0.99; p = 0.008) and a MACE increase began below a BMI of 24 kg/m². Conclusions: Lower BMI was significantly associated with higher rates of MACCE and all-cause mortality after PCI. The obesity paradox is manifested in Korean patients in the new-generation DES era.