title: The impact of preoperative weight loss before laparoscopic gastric bypass.
abstract: BACKGROUND
  The impact of preoperative weight loss on outcomes following laparoscopic Roux-en-Y gastric bypass (LRYGB) is a controversial issue. We evaluated our outcomes of LRYGB in patients who lost different amount of weight prior to surgery.
  
  
  METHODS
  Patients who underwent primary LRYGB were divided in three groups on the basis of preoperative weight loss percentage. Group A comprised 166 patients, who lost <5% of their weight preoperatively; group B comprised 239 patients who lost >5 to 10% and group C included 143 patients who lost >10%. Intra- and postoperative complications at 30 days, hospital stay, and outcomes were evaluated.
  
  
  RESULTS
  Significant difference was found in operative (mean ± SD) time [104.43 ± 36.40 min in group A, 80.08 ± 23.07 min in group B, and 76.99 ± 23.23 min in group C; p < 0.001 in group A versus group B or group C; p = 0.210 in group B versus group C]. Difference in hospital stay was significant (3.33 ± 3.22 days in group A, 2.10 ± 2.77 in group B, and 1.87 ± 1.44 in group C; p < 0.001 in group A versus groups B or C). Overall postoperative morbidity rate was 33.13% in group A, 19.25% in group B, and 11.89% in group C, with significant difference in group A versus groups B or C (p = 0.002 and p < 0.001). Mean excess weight loss was significantly higher (72.7%) in group C versus group A (63.1%) (p = 0.015) at 12 months.
  
  
  CONCLUSIONS
  Weight loss >5% prior to LRYGB may reduce morbidity, and preoperative weight loss >10% may improve weight loss outcomes at 1-year follow-up.
authors.affiliation: Department of Plastic and General Surgery, Turku University Hospital, Turku, Finland, salvatore.giordano@gmail.com.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Giordano
authors.forename: Mikael
authors.initials: M
authors.lastname: Victorzon
mesh_terms: D000328:Adult; D019317:Evidence-Based Medicine; D005260:Female; D015390:Gastric Bypass; D006801:Humans; D010535:Laparoscopy; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000453:epidemiology / Q000601:surgery*; D061646:Operative Time; D011183:Postoperative Complications / Q000453:epidemiology*; D011300:Preoperative Care / Q000379:methods; D012189:Retrospective Studies; D040242:Risk Reduction Behavior; D016896:Treatment Outcome; D015431:Weight Loss