The impact of obesity on the short-term andlong-term outcomes after percutaneous coronary intervention: the obesity paradox?

Objectives The purpose of this study was to assess the impact of body mass index (BMI) on the short- and long-term outcomes after percutaneous coronary intervention (PCI). Background Obesity is associated with advanced coronary artery disease (CAD). However, the relation between BMI and outcome after PCI remains controversial. Methods We studied 9,633 consecutive patients who underwent PCI between January 1994 and December 1999. Patients were divided into three groups according to BMI: normal, BMI between 18.5 and 24.9 (n = 1,923); overweight, BMI between 25 and 30 (n = 4,813); and obese, BMI >30 (n = 2,897). Results Obese patients were significantly younger and had consistently worse baseline clinical characteristics than normal or overweight patients, with a higher incidence of hypertension, diabetes, hypercholesterolemia and smoking history (p < 0.0001). Despite similar angiographic success rates among the three groups, normal BMI patients had a higher incidence of major in-hospital complications, including cardiac death (p = 0.001). At one-year follow-up, overall mortality rates were significantly higher for normal BMI patients compared with overweight or obese patients (p < 0.0001). Myocardial infarction and revascularization rates did not differ among the three groups. By multivariate Cox regression analysis, diabetes, hypertension, age, BMI and left ventricular function were independent predictors of long-term mortality. Conclusions In patients with known CAD who undergo PCI, very lean patients (BMI <18.5) and those with BMI within the normal range are at the highest risk for in-hospital complications and cardiac death and for increased one-year mortality.