Abstract 13916: The Obesity Paradox in ST-elevation Myocardial Infarction

Abstract

Introduction: In patients with known cardiovascular disease (CVD), body mass index (BMI)-defined obesity has been found to be protective against all-cause mortality and CVD events, commonly known as the “obesity paradox”. However, the role of BMI in STEMI outcomes remains poorly understood. Methods: The Midwest STEMI Consortium database of 15,039 consecutive STEMI activations between January 2010 and December 2020 consists of four regional STEMI centers. Using data from two centers with complete follow-up available, Minneapolis Heart Institute and The Christ Hospital, we examined differences by BMI groups defined as normal (18.5-24.9 kg/m 2 ), overweight (25.0-29.9 kg/m 2 ), and obese (≥30.0 kg/m 2 ) in baseline characteristics, treatment, in-hospital death and 1-year MACE and mortality risk. Results: Among 4,682 patients (22% normal BMI, 36% overweight and 42% obese), obese patients were significantly younger but had higher rates of hypertension, diabetes, dyslipidemia, and were taking more cardiac medications prior to admission. Systolic and diastolic blood pressures, heart rate, and creatinine were highest in the obese subgroup. Obese patients had a higher rate of out of hospital cardiac arrest (9.2% vs. 9.6% vs. 12%, p=0.02) and a trend towards higher in-hospital death (5.7% vs. 4.7% vs. 6.4%, p=0.08). Overweight and obese patients had a lower risk of 1-year mortality (4.6% vs. 2.6% vs. 2.9%) and a trend towards lower 1-year MACE events (7.6% vs. 5.5% vs. 5.9%) compared to normal BMI patients (Figure). Discussion: Among individuals presenting with STEMI, despite more risk factors, higher rates of out of hospital cardiac arrest and a trend towards higher in-hospital death, overweight and obese patients had lower 1-year mortality consistent with the obesity paradox. Further research is needed to understand the obesity paradox in STEMI patients.