title: Is body mass index a risk factor for isolated off-pump coronary revascularization?
abstract: OBJECTIVE
  The influence of body mass index (BMI) as a risk factor for isolated off-pump coronary artery bypass (OPCAB) surgery is unknown. We postulated that BMI ≥ 30 kg/m(2) would adversely affect outcomes following OPCAB at our institution.
  
  
  METHODS
  From 2002 to 2009, we selected 742 patients (primary, N = 709 [95.6%], re-operative, N = 33 [4.45%]) who underwent isolated OPCAB for analysis. Patients were stratified into groups by BMI: non-obese (BMI < 30 kg/m(2) ) and obese (BMI ≥ 30 kg/m(2)). Preoperative risk, operative characteristics, and postoperative outcomes were analyzed. Risk-adjusted models evaluated the occurrence of any complication and mortality.
  
  
  RESULTS
  Overall crude mortality was 1.5% (11/742). When compared to non-obese (26.12 ± 2.72 kg/m(2)) recipients, the obese (35.81 ± 5.69 kg/m(2)) comprised younger patients (62.46 ± 9.96 years, p < 0.001). Number of diseased vessels, Left ventricular ejection fraction, and baseline renal function was equivalent across groups. Diabetes (53.24%) and hypertension (90.59%) were more prevalent among obese patients (p < 0.001, respectively). Internal mammary artery utilization (p = 0.47), endoscopic vein harvest (p = 0.74), and intra-aortic balloon pump use (p = 0.58) were similar between groups. Interestingly, postoperative blood product requirement was lower in obese versus non-obese recipients (47.35% vs. 56.72%, p < 0.01). Furthermore, intensive care unit stay (p = 0.93), mortality (p = 0.56), and discharge to home (p = 0.09) remained equivalent between groups. Importantly, multivariable logistic regression did not identify BMI ≥ 30 kg/m(2) as an independent predictor of any complication (p = 0.21) or mortality (p = 0.74).
  
  
  CONCLUSIONS
  Obesity does not influence operative characteristics or effect outcomes after OPCAB. BMI ≥ 30 kg/m(2) should not be considered a prohibitive risk factor in isolated off-pump coronary revascularization.
authors.affiliation: Department of Surgery, Division of Cardiothoracic Surgery, State University of New York Upstate Medical University School of Medicine, Syracuse, New York 13210, USA.
authors.forename: Castigliano M
authors.initials: CM
authors.lastname: Bhamidipati
authors.forename: Keri A
authors.initials: KA
authors.lastname: Seymour
authors.forename: Noah
authors.initials: N
authors.lastname: Cohen
authors.forename: Roberta
authors.initials: R
authors.lastname: Rolland
authors.forename: Karikehalli A
authors.initials: KA
authors.lastname: Dilip
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Lutz
mesh_terms: D000368:Aged; D015992:Body Mass Index; D047549:Coronary Artery Bypass, Off-Pump / Q000379:methods*; D003324:Coronary Artery Disease / Q000150:complications / Q000401:mortality / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009518:New York / Q000453:epidemiology; D009765:Obesity / Q000150:complications* / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends