title: Volumetric fat ratio and not body mass index is predictive of ileocolectomy outcomes in Crohn's disease patients.
abstract: BACKGROUND
  Crohn's disease (CD) patients are typically underweight; however, a growing cohort of overweight CD patients is emerging. The current study investigates whether body mass index (BMI) or volumetric fat parameters can be used to predict morbidity after ileocolectomy for CD.
  
  
  METHODS
  One hundred and forty-three CD patients who underwent elective ileocolectomy were identified from our Inflammatory Bowel Disease (IBD) Registry. Patient demographics and operative outcomes were recorded. Visceral (VA) and subcutaneous (SA) adiposity and abdominal circumference (AC) were analyzed on preoperative CT scans using Aquarius iNtuition software. A visceral/subcutaneous ratio (VSR) was calculated.
  
  
  RESULTS
  BMI correlated with SA (p = 0.0001), VA (p = 0.0001) and AC (p = 0.0001) but not VSR (p > 0.05). BMI, VA and AC did not predict surgical morbidity (p > 0.05). In multivariate regression analysis, family history of IBD (p = 0.009), high American Society of Anesthesiologists score (p = 0.02) and increased VSR (p = 0.03) were independent predictors of postoperative morbidity.
  
  
  CONCLUSIONS
  The visceral/subcutaneous fat ratio is a more reliable predictor of postoperative outcomes in CD patients undergoing ileocolectomy than conventional adiposity markers such as BMI. Preoperative calculation of the visceral/subcutaneous fat ratio offers the opportunity to optimize high-risk surgical patients, thus improving outcomes.
authors.affiliation: Division of Colon and Rectal Surgery, Department of Surgery, College of Medicine, The Pennsylvania State University, Hershey, Pa., USA.
authors.forename: Tara M
authors.initials: TM
authors.lastname: Connelly
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Juza
authors.forename: William
authors.initials: W
authors.lastname: Sangster
authors.forename: Rishabh
authors.initials: R
authors.lastname: Sehgal
authors.forename: Rafel F
authors.initials: RF
authors.lastname: Tappouni
authors.forename: Evangelos
authors.initials: E
authors.lastname: Messaris
mesh_terms: D000328:Adult; D000714:Anastomosis, Surgical / Q000379:methods; D050218:Body Fat Distribution; D015992:Body Mass Index; D015331:Cohort Studies; D003082:Colectomy / Q000009:adverse effects / Q000379:methods; D003106:Colon / Q000601:surgery; D003424:Crohn Disease / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D017558:Elective Surgical Procedures / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007082:Ileum / Q000601:surgery; D050152:Intra-Abdominal Fat; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology / Q000503:physiopathology; D011237:Predictive Value of Tests; D011300:Preoperative Care / Q000379:methods; D012042:Registries; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D050151:Subcutaneous Fat; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D055815:Young Adult