CHICAGO – The obesity paradox has emerged among coronary artery bypass graft surgery patients in New Jersey. That is, a fat patient undergoing CABG in the state is significantly more likely to be alive several years later than is a normal-weight person.
Analysis of 60,635 patients in the state’s vaunted, ground-breaking Myocardial Infarction Data Acquisition System (MIDAS) database who underwent an isolated CABG procedure during 1998-2007 showed a significantly greater mortality in normal-weight patients as compared with those who were overweight or obese, through 2 years of postsurgical follow-up, according to Dr. Yingzi Deng of Robert Wood Johnson Medical School, New Brunswick, N.J.
For example, from 90 days through 2 years post CABG, all-cause mortality in 13,306 normal-weight patients was 6.3%, compared with 4.1% in 25,648 overweight patients and 3.8% in 21,681 obese patients, she reported at the conference.
This translated to a 29% reduction in the relative risk of death in overweight and a 30% decrease in mortality risk in obese patients in a multivariate analysis adjusted for numerous potential confounders including age, gender, year of surgery, smoking status, diabetes, hypertension, chronic renal or pulmonary disease, left main disease, and ejection fraction.
Earlier studies had shown that better short-term outcomes in CABG patients who were overweight or obese patients (J. Am. Coll. Cardiol. 2003;42:668-76). The MIDAS registry study reflecting the statewide New Jersey experience provided a unique opportunity to see how body mass index affects long-term survival following CABG.
The obesity paradox has also been shown to pertain to patients undergoing percutaneous coronary intervention, as well as to patients hospitalized for acute deterioration of heart failure. The explanation for this intriguingly counterintuitive phenomenon remains unclear.
Dr. Deng reported having no financial conflicts.