title: Evaluation of the obesity surgery mortality risk score for the prediction of postoperative complications after primary and revisional laparoscopic Roux-en-Y gastric bypass.
abstract: BACKGROUND
  The Obesity Surgery Mortality Risk Score (OS-MRS) is a validated instrument for mortality risk prediction in patients undergoing laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures classifying patients into low risk (class A), intermediate risk (class B), and high risk (class C).
  
  
  OBJECTIVE
  The primary aim of this study was to evaluate the accuracy of the OS-MRS in predicting postoperative complications after LRYGB. Secondarily, the postoperative complication rate between primary and revisional LRYGB was systematically analyzed.
  
  
  METHODS
  The Obesity Center Amsterdam, located in a large teaching hospital, in Amsterdam, The Netherlands.
  
  
  METHODS
  The OS-MRS was applied to a consecutive database of patients who underwent LRYGB from November 2007 onwards. Postoperative complications were scored according to the Clavien-Dindo classification. Revisional LRYGB was separately analyzed.
  
  
  RESULTS
  LRYGB was performed in 1667 patients either as a primary (81.5%) or revisional (18.5%) procedure. The majority (n = 1371, 82.2%) were female, mean age 44.6 (standard deviation 14.4) years and mean body mass index 44.2 (6.5) kg/m2. Nine hundred and four (54.2%) were OS-MRS class A, 642 class B (38.5%), and 121 (7.3%) class C. Complications occurred in 143 (10.5%) and 44 (14.2%) patients after primary and revisional surgery, respectively. In both primary and revisional LRYGB, there was no association between complications and the OS-MRS classification. Subanalysis comparing primary with revisional LRYGB found a significant association between revisional surgery and the development of severe complications (Clavien-Dindo≥3) (P = .003) and mortality (P = .017).
  
  
  CONCLUSIONS
  The OS-MRS was not an accurate predictor for postoperative complications in patients who underwent primary or revisional LRYGB. As in other studies, revisional surgery is an independent risk factor for the development of severe complications.
authors.affiliation: Department of Surgery, Sint Lucas Andreas Ziekenhuis, Amsterdam, The Netherlands. Electronic address: u.coblijn@slaz.nl.
authors.forename: Usha K
authors.initials: UK
authors.lastname: Coblijn
authors.affiliation: Department of Surgery, Academisch Medisch Centrum, Amsterdam, The Netherlands.
authors.forename: Sjoerd M
authors.initials: SM
authors.lastname: Lagarde
authors.affiliation: Department of Surgery, Sint Lucas Andreas Ziekenhuis, Amsterdam, The Netherlands.
authors.forename: Christel A L
authors.initials: CA
authors.lastname: de Raaff
authors.affiliation: Department of Surgery, Onze Lieve Vrouwe Gasthuis, Amsterdam, The Netherlands.
authors.forename: Steve M
authors.initials: SM
authors.lastname: de Castro
authors.affiliation: Department of Surgery, Sint Lucas Andreas Ziekenhuis, Amsterdam, The Netherlands.
authors.forename: Willem F
authors.initials: WF
authors.lastname: van Tets
authors.affiliation: Department of Surgery, Vrije Universiteit Medisch Centrum, Amsterdam, The Netherlands.
authors.forename: H
authors.initials: H
authors.lastname: Jaap Bonjer
authors.affiliation: Department of Surgery, Sint Lucas Andreas Ziekenhuis, Amsterdam, The Netherlands.
authors.forename: Bart A
authors.initials: BA
authors.lastname: van Wagensveld
mesh_terms: D000328:Adult; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000401:mortality; D050171:Dyslipidemias / Q000150:complications / Q000401:mortality; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects* / Q000401:mortality; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000401:mortality; D010535:Laparoscopy / Q000009:adverse effects* / Q000401:mortality; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D009767:Obesity, Morbid / Q000150:complications / Q000401:mortality / Q000601:surgery*; D011182:Postoperative Care; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality; D012086:Reoperation / Q000401:mortality; D012189:Retrospective Studies; D018570:Risk Assessment; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000401:mortality
keywords: Clavien-Dindo; Complication; Laparoscopic Roux-en-Y gastric bypass; Obesity Surgery Mortality Risk Score; Prediction