Association of body mass index with mortality in Chinese patients after percutaneous coronary intervention: A large single-center data.

BACKGROUND: Although numerous studies, to date, have demonstrated a specific phenomenon called the "obesity paradox" in patients after percutaneous coronary intervention (PCI), studies performed in China thus far have consistently shown an absence of this phenomenon.

HYPOTHESIS: "Obesity paradox" does exist in Chinese PCI patients.

METHODS: 10 724 consecutive Chinese patients who had undergone PCI treatment at a single center from January 2013 to December 2013 were prospectively recruited. Patients were divided into four groups: underweight (body mass index [BMI<18.5 kg/m2 ]), normal weight (18.5 kg/m2 ≤BMI<24.0 kg/m2 ), overweight (24.0 kg/m2 ≤BMI<28.0 kg/m2 ), and obese (BMI≥28.0 kg/m2 ). Two-year clinical outcomes were compared across the groups.

RESULTS: Overall, mean (±SD) BMI of all the patients was 25.9±3.2 kg/m2 . The 2-year mortality across underweight, normal weight, overweight, and obese patients in different BMI groups was 2.2%, 1.7%, 1.1%, and 1.0%, respectively (P=.035). Kaplan-Meier curves revealed that normal weight patients had higher incidence of all-cause mortality than overweight and obese (P=.015 and P=.020, respectively). Multivariable Cox regression analysis indicated that overweight was an independent predictor of all-cause mortality compared with normal weight (HR 0.64, 95% CI 0.41-0.98, P=.042).

CONCLUSIONS: Overweight patients have lower risk of mortality after PCI treatment; therefore, the phenomenon of "obesity paradox" also seems to exist in Chinese PCI patients.