title: Treatment Success: Investigating Clinically Significant Change in Quality of Life Following Bariatric Surgery.
abstract: One of the most important outcomes following bariatric surgery is an improvement in health-related quality of life (QOL). This study aimed to explore what degree of weight loss is required after bariatric surgery in order to achieve a clinically significant change in QOL from pre-surgery to 4 to 5 years after surgery.
  
  
  
  Participants were assessed prior to having surgery (N = 280) and were invited to participate in a follow-up study 4 to 5 years after surgery. Sixty-seven of the original participants agreed to take part and completed a Web-based survey, which included the Impact of Weight on Quality of Life-Lite (IWQOL-Lite) questionnaire. Several analyses were conducted to examine the association between weight loss and clinically significant change in QOL.
  
  
  
  Mean age was 48.13 ± 10.37 years, 51 (76%) were female, 62 (92.5%) Caucasian, and mean baseline body mass index (BMI) was 41.11 ± 6.03 kg/m2. The mean percent of excess weight loss (EWL) was 46% (17% total weight loss), and 64% (n = 43) achieved a clinically significant change in QOL. The majority of those who lost ≥40% EWL had a clinically significant change in QOL, and their odds of achieving this change were 2.81 times higher than those that did not.
  
  
  
  Results indicated that an EWL of ≥40% may be sufficient for the majority of patients to achieve clinically significant change, but that ≥50% is a better predictor of clinically significant change.
authors.affiliation: School of Surgery, University of Western Australia (M507), 35 Stirling Highway, Crawley, WA, 6009, Australia. claire.reynolds@research.uwa.edu.au.|School of Psychology, University of Western Australia (M304), 35 Stirling Highway, Crawley, WA, 6009, Australia. claire.reynolds@research.uwa.edu.au.
authors.forename: Claire L
authors.initials: CL
authors.lastname: Reynolds
authors.affiliation: School of Psychology, University of Western Australia (M304), 35 Stirling Highway, Crawley, WA, 6009, Australia.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Byrne
authors.affiliation: School of Surgery, University of Western Australia (M507), 35 Stirling Highway, Crawley, WA, 6009, Australia.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Hamdorf
mesh_terms: D000328:Adult; D050110:Bariatric Surgery / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery*; D011788:Quality of Life; D016896:Treatment Outcome; D015431:Weight Loss
keywords: Bariatric surgery; Clinically significant change; Laparoscopic adjustable gastric banding; Quality of life; Sleeve gastrectomy