title: Patients lacking sustainable long-term weight loss after gastric bypass surgery show signs of decreased inhibitory control of prepotent responses.
abstract: BACKGROUND
  A considerable number of bariatric patients report poor long-term weight loss after Roux-en-Y gastric bypass (RYGB) surgery. One possibility for an underlying cause is an impairment of cognitive control that impedes this patient group's dietary efforts.
  
  
  OBJECTIVE
  To investigate if patients having either poor or good weight loss response, ~12 years after RYGB-surgery, differ in their ability to inhibit prepotent responses when processing food cues during attentional operations-as measure of cognitive control.
  
  
  METHODS
  In terms of weight loss following RYGB-surgery, 15 'poor responders' and 15 'good responders', matched for gender, age, education, preoperative body mass index, and years since surgery, were administered two tasks that measure sustained attention and response control: a go/no-go task and a Stroop interference task; both of which are associated with maladaptive eating behaviours.
  
  
  RESULTS
  The poor responders (vs. good responders) needed significantly more time when conducting a go/no-go task (603±134 vs. 519±44 msec, p = 0.03), but the number of errors did not differ between groups. When conducting a Stroop interference task, poor responders read fewer inks than good responders (68±16 vs. 85±10 words, p = 0.002).
  
  
  CONCLUSIONS
  Patients lacking sustainable weight loss after RYGB-surgery showed poorer inhibitory control than patients that successfully lost weight. In the authors' view, these results suggest that cognitive behavioral therapies post-RYGB-surgery may represent a promising behavioral adjuvant to achieve sustainable weight loss in patients undergoing this procedure. Future studies should examine whether these control deficits in poor responders are food-specific or not.
authors.affiliation: Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Pleunie S
authors.initials: PS
authors.lastname: Hogenkamp
authors.affiliation: Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: Magnus
authors.initials: M
authors.lastname: Sundbom
authors.affiliation: Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Victor C
authors.initials: VC
authors.lastname: Nilsson
authors.affiliation: Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Christian
authors.initials: C
authors.lastname: Benedict
authors.affiliation: Department of Neuroscience, Uppsala University, Uppsala, Sweden.
authors.forename: Helgi B
authors.initials: HB
authors.lastname: Schiöth
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D015390:Gastric Bypass; D006801:Humans; D008875:Middle Aged; D015431:Weight Loss