BackgroundObesity is associated with cardiac disease and is known to increase the risk of post surgical complications. Such complications contribute to excess hospital costs due to extended length of stay (LOS). It is not known if there is a difference based on sex for post surgical complications and LOS. The objective of this study was to explore whether obesity is a risk factor associated with complications and extended LOS post coronary artery bypass graft (CABG) surgery.MethodsThis retrospective study used data from 7560 adult patients [1407 (19%) female] who underwent CABG between 2003 and 2014 registered in the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) database. Forty-one percent of females and 39% of males had obesity. Using normal BMI (18.5-24.9 kg/m2) as a reference group, the association of three classes of obesity with rates of operative mortality, overall early complications, subgroups of early complications (i.e., infection, renal and pulmonary complications), intensive care unit length of stay (ICU-LOS), and total LOS were separately assessed for females and males while adjusting for clinical covariates.ResultsIn both females and males, there were no differences in operative mortality, pulmonary, or renal complications between patients with normal BMI and all classes of obesity. The ratio of overall early complications was higher in patients with class III obesity only in males (adjusted odds ratio [aOR]: 1.65; 95% CI 1.24-2.20, p=0.001). All classes of obesity were independent risk factors for infection in both females (Class I: aOR: 2.07; 95% CI 1.25-3.43, p=0.005; Class II: aOR: 2.45;95% CI 1.34-4.48, p=0.004; Class III:aOR: 3.57; 95% CI 1.76-7.22, p<0.001) and males (Class I: aOR 1.49; 95% CI 1.12-2.00 p=0.006; Class II: aOR 2.32; 95% CI 1.63-3.30 p<0.001 Class III: aOR 3.27: 95% CI 2.15-4.98, p<0.001). Compared to patients with normal BMI, only female patients with class III obesity had longer adjusted ICU-LOS (2.4 days, 95% CI 0.3 to 4.5, p=0.028) and total LOS (8.8 days, 95% CI 4.5 to 13.1, p<0.001).ConclusionsBMI ≥40 kg/m2 was an independent risk factor for the increased ICU-LOS and total LOS only in female patients. Greater perioperative attention and intervention may be required for female patients to improve patient outcomes and reduce healthcare cost. BackgroundObesity is associated with cardiac disease and is known to increase the risk of post surgical complications. Such complications contribute to excess hospital costs due to extended length of stay (LOS). It is not known if there is a difference based on sex for post surgical complications and LOS. The objective of this study was to explore whether obesity is a risk factor associated with complications and extended LOS post coronary artery bypass graft (CABG) surgery. Obesity is associated with cardiac disease and is known to increase the risk of post surgical complications. Such complications contribute to excess hospital costs due to extended length of stay (LOS). It is not known if there is a difference based on sex for post surgical complications and LOS. The objective of this study was to explore whether obesity is a risk factor associated with complications and extended LOS post coronary artery bypass graft (CABG) surgery. MethodsThis retrospective study used data from 7560 adult patients [1407 (19%) female] who underwent CABG between 2003 and 2014 registered in the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) database. Forty-one percent of females and 39% of males had obesity. Using normal BMI (18.5-24.9 kg/m2) as a reference group, the association of three classes of obesity with rates of operative mortality, overall early complications, subgroups of early complications (i.e., infection, renal and pulmonary complications), intensive care unit length of stay (ICU-LOS), and total LOS were separately assessed for females and males while adjusting for clinical covariates. This retrospective study used data from 7560 adult patients [1407 (19%) female] who underwent CABG between 2003 and 2014 registered in the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) database. Forty-one percent of females and 39% of males had obesity. Using normal BMI (18.5-24.9 kg/m2) as a reference group, the association of three classes of obesity with rates of operative mortality, overall early complications, subgroups of early complications (i.e., infection, renal and pulmonary complications), intensive care unit length of stay (ICU-LOS), and total LOS were separately assessed for females and males while adjusting for clinical covariates. ResultsIn both females and males, there were no differences in operative mortality, pulmonary, or renal complications between patients with normal BMI and all classes of obesity. The ratio of overall early complications was higher in patients with class III obesity only in males (adjusted odds ratio [aOR]: 1.65; 95% CI 1.24-2.20, p=0.001). All classes of obesity were independent risk factors for infection in both females (Class I: aOR: 2.07; 95% CI 1.25-3.43, p=0.005; Class II: aOR: 2.45;95% CI 1.34-4.48, p=0.004; Class III:aOR: 3.57; 95% CI 1.76-7.22, p<0.001) and males (Class I: aOR 1.49; 95% CI 1.12-2.00 p=0.006; Class II: aOR 2.32; 95% CI 1.63-3.30 p<0.001 Class III: aOR 3.27: 95% CI 2.15-4.98, p<0.001). Compared to patients with normal BMI, only female patients with class III obesity had longer adjusted ICU-LOS (2.4 days, 95% CI 0.3 to 4.5, p=0.028) and total LOS (8.8 days, 95% CI 4.5 to 13.1, p<0.001). In both females and males, there were no differences in operative mortality, pulmonary, or renal complications between patients with normal BMI and all classes of obesity. The ratio of overall early complications was higher in patients with class III obesity only in males (adjusted odds ratio [aOR]: 1.65; 95% CI 1.24-2.20, p=0.001). All classes of obesity were independent risk factors for infection in both females (Class I: aOR: 2.07; 95% CI 1.25-3.43, p=0.005; Class II: aOR: 2.45;95% CI 1.34-4.48, p=0.004; Class III:aOR: 3.57; 95% CI 1.76-7.22, p<0.001) and males (Class I: aOR 1.49; 95% CI 1.12-2.00 p=0.006; Class II: aOR 2.32; 95% CI 1.63-3.30 p<0.001 Class III: aOR 3.27: 95% CI 2.15-4.98, p<0.001). Compared to patients with normal BMI, only female patients with class III obesity had longer adjusted ICU-LOS (2.4 days, 95% CI 0.3 to 4.5, p=0.028) and total LOS (8.8 days, 95% CI 4.5 to 13.1, p<0.001). ConclusionsBMI ≥40 kg/m2 was an independent risk factor for the increased ICU-LOS and total LOS only in female patients. Greater perioperative attention and intervention may be required for female patients to improve patient outcomes and reduce healthcare cost. BMI ≥40 kg/m2 was an independent risk factor for the increased ICU-LOS and total LOS only in female patients. Greater perioperative attention and intervention may be required for female patients to improve patient outcomes and reduce healthcare cost.