title: Effect of BMI on outcomes in proctectomy.
abstract: BACKGROUND
  The unique surgical challenges of proctectomy may be amplified in obese patients. We examined surgical outcomes of a large, diverse sample of obese patients undergoing proctectomy.
  
  
  OBJECTIVE
  The purpose of this work was to determine whether increased BMI is associated with increased complications in proctectomy.
  
  
  METHODS
  This was a retrospective review.
  
  
  METHODS
  The study uses the American College of Surgeons National Surgical Quality Improvement Program database (2010 and 2011).
  
  
  METHODS
  Patients included were those undergoing nonemergent proctectomy, excluding rectal prolapse cases. Patients were grouped by BMI using the World Health Organization classifications of underweight (BMI <18.5); normal (18.5-24.9); overweight (25.0-29.9); and class I (30.0-34.9), class II (35.0-39.9), and class III (≥40.0) obesity.
  
  
  METHODS
  We analyzed the effect of preoperative and intraoperative factors on 30-day outcomes. Continuous variables were compared with Wilcoxon rank-sum tests and proportions with the Fisher exact or χ tests. Logistic regression controlled for the effects of multiple risk factors.
  
  
  RESULTS
  Among 5570 patients, class I, II, and III obesity were significantly associated with higher rates of overall complications (44.0%, 50.8%, and 46.6% vs 38.1% for normal-weight patients; p < 0.05). Superficial wound infection was significantly higher in classes I, II, and III (11.6%, 17.8%, and 13.0% vs 8.0% for normal-weight patients; p < 0.05). Operative times for patients in all obesity classes were significantly longer than for normal-weight patients. On multivariate analysis, an obese BMI independently predicted complications; ORs (95% CIs) were 1.36 (1.14-1.62) for class I obesity, 1.99 (1.54-2.54) for class II, and 1.42 (1.02-1.96) for class III.
  
  
  CONCLUSIONS
  This study was a retrospective design with limited follow-up.
  
  
  CONCLUSIONS
  Class I, II, and III obese patients were at significantly increased risk for morbidity compared with normal BMI patients. Class II obese patients had the highest rate of complications, a finding that deserves further investigation.
authors.affiliation: 1Department of Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa 2Department of Epidemiology, University of Iowa College of Public Health, Iowa City, Iowa.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Hrabe
authors.forename: Scott K
authors.initials: SK
authors.lastname: Sherman
authors.forename: Mary E
authors.initials: ME
authors.lastname: Charlton
authors.forename: John W
authors.initials: JW
authors.lastname: Cromwell
authors.forename: John C
authors.initials: JC
authors.lastname: Byrn
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D061646:Operative Time; D011183:Postoperative Complications; D011351:Proctoscopy / Q000379:methods*; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome