Clustering of Metabolic Abnormalities Among Obese Patients and Mortality After Percutaneous Coronary Intervention

Although current literature demonstrates metabolic abnormalities are associated with mortality, obese patients who tend to have more metabolic abnormalities paradoxically have lower overall mortality rates compared to their normal-weight counterparts. In this study, we examined the prevalence of metabolic abnormality clustering and its relation to mortality in obese and normal-weight patients after percutaneous coronary intervention (PCI). Patients (n = 9,673) undergoing elective PCI from October 2003 through December 2006 at a single urban hospital were categorized by body mass index (BMI) levels of 18.5 to 24.9, 25.0 to 29.9, 30.0 to 34.9, and ≥35 kg/m2 and by number of metabolic abnormalities possessed (hypertension, impaired fasting glucose/diabetes, triglycerides ≥150 mg/dl, high-density lipoprotein cholesterol < 40 mg/dl, and C-reactive protein ≥2.0 mg/L). All-cause mortality was assessed through June 30, 2007. Mean age of patients was 65.9 years and 66% were men. Prevalences of 4 or 5 metabolic abnormalities were 12%, 18%, 24%, and 31% in patients with BMI levels of 18.5 to 24.9, 25.0 to 29.9, 30 to 34.9, and ≥35 kg/m2, respectively. In patients with BMI of 30.0 to 34.9 kg/m2, hazard ratios (95% confidence intervals) for mortality associated with 2, 3, and 4 to 5 metabolic abnormalities versus 0 to 1 metabolic abnormality were 1.31 (0.79 to 2.17), 1.42 (0.83 to 2.43), and 2.39 (1.24 to 4.59), respectively. Analogous hazard ratios for patients with BMI ≥35 kg/m2 were 1.94 (0.90 to 4.20), 1.44 (0.63 to 3.28), and 2.17 (0.91 to 5.18). All-cause mortality rates per 1,000 person-years were 55.5, 33.7, 28.3, and 33.8 in patients with BMI levels of 18.5 to 24.9, 25 to 29.9, 30 to 34.9, and ≥35 kg/m2, respectively. In conclusion, BMI levels of 25.0 to 29.9 and 30 to 34.9 kg/m2 were associated with lower all-cause mortality after PCI. However, an increased number of metabolic abnormalities translated into increased all-cause mortality.