OBESITY IS NOT ASSOCIATED WITH A DIFFERENTIAL OUTCOME FOLLOWING CORONARY ARTERY BYPASS SURGERY

Background: Conflicting data exists regarding the impact of obesity on mortality and morbidity following coronary artery bypass graft (CABG) surgery with some suggesting a paradoxical reduction in adverse outcomes. We aimed to compare the in-hospital outcomes of CABG in obese and non-obese subjects. Methods: The Nationwide Inpatient Sample for years 2003- 2014 was used to identify adults (age ≥18 years) who underwent isolated CABG. Results: A total of 2,297,932 patients underwent CABG of which 554,857 (28.2%) surgeries were for acute coronary syndrome (ACS) and 1,743075 (74.2%) were elective. Obese patients in either group were younger, were more likely to be female and had more co-morbidities at baseline (Table 1). There was no difference in adjusted all-cause mortality in obese versus non-obese patients with ACS (2.7%-vs-4.2%, OR=1.03, 95% CI=0.98-1.07, p=0.25) or elective (0.9%-vs-1.5%, OR=0.98, 95% CI=0.94-1.03, p=0.47) CABG. Adjusted rates of acute kidney injury requiring dialysis and of wound infection were higher among obese patients whereas those of acute stroke were lower. Rates of blood transfusion were lower in obese patients undergoing CABG for ACS but not for elective indications. Obese patients with and without ACS more often received internal mammary artery grafts (90.8%-vs-88.5%, P\u3c0.001). Conclusion: Data from this comprehensive national database did not show a significant difference in in-hospital mortality among obese and non-obese patients undergoing CABG surgery