Canadian Journal of Cardiology
Clinical Research| Volume 32, ISSUE 3, P327-335, March 2016

The Underestimated Belly Factor: Waist Circumference Is Linked to Significant Morbidity Following Isolated Coronary Artery Bypass Grafting



      Waist circumference (WC) and body mass index (BMI) are clinically used to assess adiposity. The aim of the present study was to evaluate the association of WC with postoperative morbidity and mortality in patients who underwent isolated coronary artery bypass grafting (CABG) in relation to patients' BMI category.


      We analyzed the associations of WC and BMI with short-term postoperative outcomes in a cohort of 7446 patients who underwent isolated CABG. We performed univariate and adjusted analyses on main postoperative outcomes after CABG for WC and BMI.


      Adverse events researched included postoperative mortality, intensive care unit and hospital length of stay, cardiovascular and cerebrovascular events, respiratory complications, infectious, hemostasis complications, and renal complications. WC was independently associated with all postoperative outcomes except prolonged intubation and mortality. Overall, patients in the upper WC quartile in each BMI category were at increased risk of adverse events compared with patients in the lower 3 WC quartiles, with a maximal incremental risk of 1.91 (95% confidence interval, 1.23-2.95) among patients with a BMI ≥ 35. This association was observed for men and women, across all overweight and obesity categories. Neither WC nor BMI was associated with short-term postoperative mortality.


      In our large cohort of patients who underwent isolated CABG, WC was significantly associated with clinical adverse events, independently of BMI. These findings provide further evidence on the added value of measuring WC as a simple and easy to measure anthropometric marker to refine risk assessment beyond BMI among patients who undergo CABG.



      Dans la pratique clinique, le tour de taille et l’indice de masse corporelle (IMC) sont utilisés pour évaluer l’adiposité. Le but de la présente étude consistait à évaluer le lien entre le tour de taille et la morbidité/mortalité postopératoires chez des patients ayant subi un pontage aorto-coronarien isolé en relation avec leur catégorie d’IMC.


      Nous avons analysé le lien entre le tour de taille, l’IMC et les résultats postopératoires à court terme dans une cohorte de 7 446 patients ayant subi un pontage aorto-coronarien isolé. Nous avons réalisé des analyses univariées multivariées avec ajustement sur les principaux résultats postopératoires après un pontage aorto-coronarien, pour le tour de taille et l’IMC.


      Les événements indésirables analysés comprenaient la mortalité postopératoire, la durée du séjour à l’hôpital et aux soins intensifs, les manifestations cardiovasculaires et vasculaires cérébrales, les complications respiratoires, les infections, l’hémostasie et les complications rénales. Nous avons établi association indépendante entre le tour de taille et tous les résultats postopératoires, à l’exception de l’intubation prolongée et de la mortalité. D’une manière générale, les patients ayant un tour de taille se situant dans le quartile supérieur dans chacune des catégories d’IMC étaient exposés à un risque accru d’événements indésirables, comparativement à ceux dont le tour de taille se situait dans les trois quartiles inférieurs, le rapport de cote maximal étant de 1,91 (intervalle de confiance à 95 % : 1,23 – 2,95) chez les patients dont l’IMC était ≥ 35. Cette association a été observé chez les hommes et chez les femmes, dans toutes les catégories de surpoids et d’obésité. Ni le tour de taille ni l’IMC n’ont été associés à la mortalité postopératoire à court terme.


      Dans notre vaste cohorte de patients ayant subi un pontage aorto-coronarien isolé, une association significative a été étabeli entre le tour de taille et certains événements indésirables cliniques, indépendamment de l’IMC. Ces résultats viennent confirmer l’intérêt du tour de taille en tant que marqueur anthropométrique simple et facile à mesurer pour mieux évaluer le risque, au-delà de l’IMC, chez les patients qui subissent un pontage aorto-coronarien.
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