Obesity and clinical restenosis after coronary stent placement

Abstract

Background: Obesity has been associated with improved clinical outcomes after percutaneous coronary intervention--"obesity paradox."

Methods: We studied 6186 patients pooled from 6 major coronary stent clinical trials. Clinical restenosis was defined as target lesion revascularization (TLR) at 1 year. Body mass index was classified according to World Health Organization criteria as underweight (< 18.5 kg/m2), normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), obesity class I (30-34.9 kg/m2), and obesity class II/III (> or = 35 kg/m2). Multivariable logistic regression analysis was used to evaluate the effect of obesity class on TLR.

Results: Compared with normal-weight patients, there was a trend to more frequent TLR in patients of obesity class II/III (13.6% vs 10.9%, P = .08). After adjustment for previously defined predictors of TLR, other than the obesity-related intermediate states of diabetes and hypertension, obesity class II/III was associated with 1.33-fold (95% CI 1.00-1.78) higher odds of TLR. In an analysis restricted to patients without diabetes or hypertension, obesity class II/III was also associated with significantly higher odds of undergoing TLR (odd ratio [OR] 2.14, 95% CI 1.21-3.77).

Conclusion: After coronary stenting, the odds of undergoing TLR were higher in patients with obesity class II/III compared with normal-weight patients. The significant association of severe obesity in nondiabetic and normotensive patients suggests that other obesity-associated mechanisms such as insulin resistance and inflammation should be further explored.