Effect of BMI on outcomes in proctectomy

Dis Colon Rectum. 2014 May;57(5):608-15. doi: 10.1097/DCR.0000000000000051.

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.

Design: This was a retrospective review.

Settings: The study uses the American College of Surgeons National Surgical Quality Improvement Program database (2010 and 2011).

Patients: 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.

Main outcome measures: 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.

Limitations: 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.

MeSH terms

  • Adult
  • Aged
  • Body Mass Index*
  • Female
  • Humans
  • Length of Stay / statistics & numerical data
  • Male
  • Middle Aged
  • Obesity / complications*
  • Operative Time
  • Postoperative Complications
  • Proctoscopy / methods*
  • Retrospective Studies
  • Risk Factors
  • Treatment Outcome