Abstract

Background: Previous studies have reported conflicting findings regarding the relation of body mass index (BMI) to outcomes following percutaneous coronary interventions (PCI). No study to date has directly examined the effect of obesity on cardiovascular thrombotic events after stent implantation.

Objective: To evaluate the effect of obesity on cardiovascular thrombotic events in patients undergoing PCI with drug-eluting stents.

Methods: We studied 4972 patients between January 2004 and December 2006. Patients were divided into three groups according to body mass index: normal (BMI <24.9 kg/m², n = 1284), overweight (BMI 25–29.9 kg/m², n = 2475) and obese (BMI ⩾30 kg/m², n = 1213). Median follow-up was 26 (interquartile range 20–33) months.

Results: Composite cardiovascular thrombotic events, including cardiac death and non-fatal myocardial infarction, were significantly higher in obese patients (5.9%) than in normal (3.2%) and overweight (3.8%) patients (p = 0.001). The incidence of definite or probable stent thrombosis steadily increased with increasing body mass index (0.9% vs 1.0% vs 1.9% in normal, overweight and obese patients, respectively; p = 0.029). Multivariate analyses showed that obesity was an independent predictor of 3-year composite thrombotic events (hazard ratio 1.86; 95% confidence interval 1.25 to 2.75; p = 0.003) and definite or probable stent thrombosis (2.17; 1.04 to 4.55; p = 0.040).

Conclusions: Obese patients have a higher risk for long-term cardiovascular thrombotic events following PCI with drug-eluting stents than patients with normal weight.