title: The Effect of Obesity on Perioperative Outcomes for Open and Minimally Invasive Prostatectomy.
abstract: OBJECTIVE
  To compare the impact of obesity on perioperative outcomes between open radical prostatectomy (ORP) and minimally invasive prostatectomy (MIP).
  
  
  METHODS
  Using the National Surgical Quality Improvement Program public use files for 2008-2013, we identified patients undergoing prostatectomy using Current Procedural Terminology codes. Those without body mass index (BMI) or comorbidity information were excluded. BMI was treated as a categorical variable according to the World Health Organization classification. Demographic and comorbid conditions were compared between BMI groups, and multivariable logistical regression was used to identify independent predictors of adverse perioperative events.
  
  
  RESULTS
  We identified 17,693 MIP and 4674 ORP for analysis. Of the entire cohort, only 18.7% had a BMI within the normal range (18.5-24.9), whereas the remaining 81.3% were at least overweight (BMI > 25). Class I, II, and III obesity accounted for 25.0%, 7.0%, and 2.3% of the cohort, respectively. Overall, complications were higher with ORP (19.0%) than with MIP (5.3%), which held true across all BMI categories. The rate of wound, renal, thromboembolic, infectious, neurologic, Clavien grade III-V, and overall complications among MIP were directly related to BMI. Only wound and renal complications were related to BMI in ORP. In multivariable analysis, obesity was found to be an independent predictor of wound, renal, and thromboembolic complications.
  
  
  CONCLUSIONS
  Obesity has a larger impact on morbidity for MIP compared to ORP. Overall morbidity, however, remains lower for MIP across all BMI groups.
authors.affiliation: Department of Surgery, Section of Urology, The University of Chicago, Chicago, IL. Electronic address: scott.johnson@uchospitals.edu.
authors.forename: Scott C
authors.initials: SC
authors.lastname: Johnson
authors.affiliation: Department of Surgery, Section of Urology, The University of Chicago, Chicago, IL.
authors.forename: Vignesh T
authors.initials: VT
authors.lastname: Packiam
authors.affiliation: Department of Surgery, Section of Urology, The University of Chicago, Chicago, IL.
authors.forename: Shay
authors.initials: S
authors.lastname: Golan
authors.affiliation: Department of Surgery, Section of Urology, The University of Chicago, Chicago, IL.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Cohen
authors.affiliation: Department of Surgery, Section of Urology, The University of Chicago, Chicago, IL.
authors.forename: Charles U
authors.initials: CU
authors.lastname: Nottingham
authors.affiliation: Department of Surgery, Section of Urology, The University of Chicago, Chicago, IL.
authors.forename: Norm D
authors.initials: ND
authors.lastname: Smith
mesh_terms: D000368:Aged; D015992:Body Mass Index; D015331:Cohort Studies; D006801:Humans; D010535:Laparoscopy / Q000009:adverse effects*; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000601:surgery; D011183:Postoperative Complications / Q000453:epidemiology*; D011468:Prostatectomy / Q000009:adverse effects*; D011471:Prostatic Neoplasms / Q000150:complications / Q000601:surgery*; D058996:Quality Improvement; D016896:Treatment Outcome