title: Weight loss prior to bariatric surgery is not a pre-requisite of excess weight loss outcomes in obese patients.
abstract: BACKGROUND
  Although weight loss before bariatric surgery may carry advantages during the surgical procedure (decreased liver volume, operation duration, and blood loss), it is still debated whether it induces a greater long-term weight loss.
  
  
  METHODS
  We conducted a retrospective analysis over 539 patients operated by the same surgeon until September 2008. Five hundred seven primary bariatric surgical procedures were performed: gastric bypass in 381, gastric banding in 97, and sleeve gastrectomy in 29. Preoperative multidisciplinary care was similar for all the patients over a period of 12 months. Relationship between weight changes during this period and the percentage of excess weight loss (%EWL) over the 48 month after surgery was analyzed by logistic regression.
  
  
  RESULTS
  No relationship could be evidenced between pre- and postoperative weight loss, regardless of the surgical technique performed. Whether patients were male or female, and whether they had an initial BMI greater or lower than 50 kg/m(2), did not make a difference in the relationship between EWL at any point and weight loss prior to surgery. Despite a large range of weight changes before surgery, there was no trend for a relationship.
  
  
  CONCLUSIONS
  This study suggests that weight loss before surgery should not be considered a pre-requisite. Although it can reduce the difficulties of the surgical procedure, advantages for long-term weight loss are not validated.
authors.affiliation: Société de Chirurgie, Clinique de l'Anjou, Angers, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Becouarn
authors.forename: Philippe
authors.initials: P
authors.lastname: Topart
authors.forename: Patrick
authors.initials: P
authors.lastname: Ritz
mesh_terms: D000328:Adult; D005260:Female; D005743:Gastrectomy / Q000379:methods*; D015390:Gastric Bypass / Q000379:methods*; D015391:Gastroplasty / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery*; D011184:Postoperative Period; D057234:Preoperative Period; D013997:Time Factors; D016896:Treatment Outcome; D015431:Weight Loss