Body mass index is an independent predictor for mediastinitis post coronary artery bypass graft surgery in Indonesia

Objective: To determine optimal cut-off of body mass index (BMI) as a predictor for mediastinitis post coronary artery bypass graft (CABG) among Indonesia population. Method: A retrospective cohort study of patients received CABG surgery at Cipto Mangunkusumo Referral Hospital in Jakarta from January 2011 to December 2017. Mediastinitis were defined according to Center for Disease Control (CDC) definition. Result: Among 706 patients, mediastinitis has been found in 35 patient (4.96%). BMI in patient with mediastinitis were significant higher than those without mediastinitis. The receiver operating characteristic (ROC) curve for BMI had an area under the curve of 0.6701 (95% CI 0.6339-0.7046). BMI at a cut-off 26.50 kg/m² with its sensitivity (62.86%) and specificity (66.17%). Multivariate analysis using obesity definition based on ROC has an adjusted OR 3.34 (95% CI 1.61-6.97). While use WHO Obesity classification has incremental adjusted odds ratio of 3.23 for overweight category rose to 4.03 for obese. Conclusion: BMI can be used to predict mediastinitis post CABG in Indonesian population. The optimal cut-off point of BMI as a predictor is 26.5 kg/m². Overweight has three times and obese has four times risk for mediastinitis.