Impact of body mass index on long-term all-cause mortality after percutaneous coronary intervention in African-Americans.

BACKGROUND: Studies on body mass index (BMI) and post-percutaneous coronary intervention (PCI) outcomes have suggested an "obesity paradox" (lower post-PCI mortality rates in obese patients compared to patients of normal weight). Hypothesis. We assessed the hypothesis that BMI is an independent predictor of post-PCI long-term mortality in African-Americans.

METHODS: We evaluated 777 patients (146 with normal BMI [BMI > 18.5 to < 25 kg/m2], 261 overweight patients [BMI > or = 25 to < 30 kg/m2], and 370 obese patients [BMI > or = 30 kg/m2]) who underwent PCI during January 2003 to August 2006.

RESULTS: After a median follow up of 4 +/- 1 years, the overall mortality rate was 10.5% (82 deaths). The survival rate was 84%, 90% and 92% in the normal BMI, overweight and obese groups, respectively (p = 0.014 by log-rank test; hazard ratio relative to the obese group was 2.2 for the normal weight and 1.2 for the overweight groups). After adjustment for baseline clinical and procedural characteristics (age, smoking history, chronic renal insufficiency, end-stage renal disease, left main coronary artery intervention, preprocedure hemoglobin, left ventricular ejection fraction and successful PCI) using a Cox proportional hazards model, there was no significant difference in the long-term all-cause mortality rate among the three groups (p = 0.93).

CONCLUSION: BMI does not appear to be an independent predictor of long-term mortality after PCI in African-Americans.