BODY MASS INDEX (BMI) AS A PREDICTOR OF OUTCOME AFTER CORONARY ARTERY BYPASS GRAFTING: AN ASIAN PERSPECTIVE

Furnaz, Shumaila

INTRODUCTION:

There is considerable literature from developed nations on the effect of body mass index (BMI) on outcomes following cardiac surgery. Increased BMI is associated with an increased postoperative morbidity.We have studied the effect of BMI on our population, using modified scale, as predictor of outcome after coronary artery bypass grafting.

METHODS:

From adult cardiac surgery database, Aga Khan University Hospital, Karachi, 1019 charts of first time isolated elective CABG patients was retrospectively reviewed from January 2006 to December 2008. We excluded patients undergoing urgent, emergency and off pump procedures. Data was analyzed on SPSS17. Logistic regression was applied to explore whether increased BMI is a predictor of in- hospital complications after CABG.

RESULTS:

Retrospective analysis of 1019 first time isolated elective CABG patients was performed. Out of them, 163(16.0%) patients had normal BMI (18.5 to 22.9 (kg/m2) while 856(84.0%) had increased BMI (≥ 23.0 (kg/m2). Operative profile shows that (888 (87.%)) patients had three vessels coronary artery disease and (970 (95.2%)) got IMA grafts. Their 30-days mortality was 0.8%. The data showed patients with higher BMI tended to have increased postoperative complications. However multivariate analysis revealed age (adj OR: 1.04; 95%C.I: 1.02, 1.06), hospital stay (adj OR: 1.07; 95% C.I: 1.04, 1.10), perfusion time (adj OR: 1.48; 95%C.I: 1.05, 2.10) and renal failure (adj OR: 1.63; 95% C.I: 1.02, 2.59) as significantly associated with in hospital complications, while increased BMI remained insignificant at P value of ≤0.05. Model was adequately fit at P=0.749 by Hosmer and Lemeshow test.

CONCLUSIONS:

This study concludes that increased BMI in itself is not a predictor of increased mortality and morbidity. Post-operative complications in first time isolated elective CABG patients is, in fact, associated with increasing age, hospital stay, perfusion time and renal failure.