title: The role of cognitive function in postoperative weight loss outcomes: 36-month follow-up.
abstract: BACKGROUND
  Cognitive dysfunction is associated with reduced postoperative weight loss up to 2 years following surgery, though the role of cognition at more extended follow-up is not yet understood. Thirty-six months following bariatric surgery, we retrospectively compared obese and non-obese patients on 12-week postoperative cognitive performance. We hypothesized that early postoperative cognitive dysfunction would predict higher body mass index (BMI) and lower percent weight loss (%WL) in the total sample at 36 month follow-up.
  
  
  METHODS
  Fifty-five individuals undergoing bariatric surgery completed cognitive testing at preoperative baseline and serial postoperative timepoints, including 12 weeks and 36 months. Cognitive test scores were normed for demographic variables. Percent weight loss (%WL) and body mass index (BMI) were calculated at 36-month follow-up.
  
  
  RESULTS
  Adjusting for gender, baseline cognitive function, and 12-week %WL, 12-week global cognitive test performance predicted 36 month postoperative %WL and BMI. Partial correlations revealed recognition memory, working memory, and generativity were most strongly related to weight loss.
  
  
  CONCLUSIONS
  Cognitive function shortly after bariatric surgery is closely linked to extended postoperative weight loss at 36 months. Further work is necessary to clarify mechanisms underlying the relationship between weight loss, durability, and cognitive function, including contribution of adherence, as this may ultimately help identify individuals in need of tailored interventions to optimize postoperative weight loss.
authors.affiliation: Kent State University, Kent, OH, USA, mspitzna@kent.edu.
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Spitznagel
authors.forename: Michael
authors.initials: M
authors.lastname: Alosco
authors.forename: Rachel
authors.initials: R
authors.lastname: Galioto
authors.forename: Gladys
authors.initials: G
authors.lastname: Strain
authors.forename: Michael
authors.initials: M
authors.lastname: Devlin
authors.forename: Robyn
authors.initials: R
authors.lastname: Sysko
authors.forename: Ross D
authors.initials: RD
authors.lastname: Crosby
authors.forename: James E
authors.initials: JE
authors.lastname: Mitchell
authors.forename: John
authors.initials: J
authors.lastname: Gunstad
mesh_terms: D000328:Adult; D050110:Bariatric Surgery; D015992:Body Mass Index; D003071:Cognition; D004032:Diet / Q000523:psychology; D015444:Exercise / Q000523:psychology; D005247:Feeding Behavior / Q000523:psychology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000523:psychology / Q000601:surgery*; D017063:Outcome Assessment, Health Care; D010349:Patient Compliance / Q000523:psychology / Q000706:statistics & numerical data; D011184:Postoperative Period; D011379:Prognosis; D012189:Retrospective Studies; D015431:Weight Loss