Abstract 4604: Prediction of Mortality by Body Mass Index: Evidence that the Obesity Paradox Extends to Patients with Stable Coronary Heart Disease
Observational studies demonstrate an obesity paradox in patients (pts) with heart failure (HF) and severe coronary heart disease (CHD) after bypass surgery, in that overweight and obese pts have better survival than normal weight or underweight pts. Whether this observation extends to pts with stable coronary heart disease (CHD) without HF is unknown. To determine the impact of body mass index (BMI) on CHD pts without HF on all-cause mortality. We enrolled 3345 (32% women, age 67±11 yrs) stable CHD pts and followed them for 2 yrs. The following were assessed at baseline: BMI, sociodemographics (i.e., age, gender, marital status, ethnicity), clinical history (i.e., diabetes, peripheral vascular disease, history of previous cardiac events), and presence of cardiac risk factors (i.e., hypertension, dyslipidemia, smoking, sedentary lifestyle). BMI was categorized for use in a Cox regression into 4 groups (Figure⇓). A total of 44 pts (1.3%) were underweight, 1071 (32%) normal weight, 1376 (41.1%) overweight and 854 (25.5%) obese. There were 105 deaths. Controlling for sociodemographic, clinical and risk factor variables, BMI was an independent predictor of mortality (p = 0.001, Figure⇓, cumulative hazard). Underweight and normal weight pts had 3.6 and 2.1 times higher risk of death than overweight or obese CHD pts. Overweight and obesity predict better survival in pts with stable CHD. Given that the obesity paradox may encompass the full range of CHD, research is needed to understand the physiologic or behavioral correlates of overweight that mitigate the negative consequences of CHD beginning early in its progression.