Abstract 11480: Obesity and Long Term Outcomes After ST-elevation Myocardial Infarction in the Elderly: Does the Paradox Extend to Extreme Obesity? : Results From the National Cardiovascular Data Registry

Abstract

Introduction: An obesity paradox exists in non-STEMI in which patients with mild obesity have lower mortality than normal weight patients. It is not known if this paradox exists among older patients with STEMI and among individuals with extreme obesity over the long term. Methods: Patients ≥65 years of age with STEMI from the NCDR ACTION Registry-GWTG who survived to hospital discharge were linked to Medicare claims data. Patients were stratified by body mass index (BMI, kg/m 2 ) into normal weight (18.5-24.9), overweight (25-29.9), class I obese (30-34.9), class II obese (35-39.9), and class III (extreme) obese categories (≥40). Multivariable Cox proportional hazards models were used to evaluate the association between BMI category and all-cause mortality for 3 years after hospital discharge. Models were adjusted for clinical and socioeconomic (SES) characteristics and in-hospital outcomes. Differences in number of days alive and out of hospital (DAOH) were also assessed. Results: Of 19,499 patients included in the analysis, 70% were overweight or obese. Normal weight patients (30%) were more likely to be older and smoke and extremely obese patients (3%) more likely to be younger, female, and black, with lower SES and more comorbidity (P≤0.001). After multivariable adjustment, a U-shaped association was observed between BMI and long term mortality. Patients with mild (class I) obesity were at lowest risk, while normal weight or extremely obese patients had higher all-cause mortality ( Figure ). Normal weight and extremely obese individuals also had lower DAOH at 3 years compared with mildly obese (median 894 vs. 950 days, respectively, P<0.05). Conclusions: The obesity paradox persists in older STEMI patients over long term with regards to death and readmission but is not seen with extreme obesity. Normal weight and extreme obesity are associated with consistently worse outcomes highlighting a need for aggressive treatment paradigms for these populations after STEMI.