Cognitive function predicts weight loss after bariatric surgery

Abstract

Background Clinically significant cognitive impairment is found in a subset of patients undergoing bariatric surgery. These difficulties could contribute to reduced adherence to postsurgical lifestyle changes and decreased weight loss. Objectives The current study is the first to prospectively examine the independent contribution of cognitive function to weight loss following bariatric surgery. Executive function/attention and verbal memory at baseline were expected to negatively predict percent excess weight loss (%EWL) and body mass index (BMI) at follow-up. Setting Three sites of the Longitudinal Assessment of Bariatric Surgery (LABS) parent project were used: Columbia, Cornell, and Neuropsychiatric Research Institute Methods Eighty-four individuals enrolled in the LABS project undergoing bariatric surgery completed cognitive evaluation at baseline. BMI and %EWL were calculated at 12-week and 12-month post-surgery follow-ups. Results Clinical impairment in task performance was most prominent in tasks associated with verbal recall and recognition (14.3–15.5% of the sample) and perseverative errors (15.5%). After accounting for demographic and medical variables, baseline tests of attention/executive function and memory predicted BMI and %EWL at 12 months, but not at 12 weeks. Conclusions Results demonstrate that baseline cognition predicts greater %EWL and lower BMI 12 months following bariatric surgery. Further work is needed to clarify the degree to which cognition contributes to adherence, and the potential mediation of cognition on the relationship between adherence and weight loss in this group.

Initial Weight Loss after Restrictive Bariatric Procedures May Predict Mid-Term Weight Maintenance: Results From a 12-Month Pilot Trial

“…Important behavioral and prognostic factors include a will to change eating habits and increase physical activity, depression score, and cognitive function. 6,9,13 Age and BMI correlate negatively with WL 6,7 and preoperative WL achieved with other treatment modalities correlates positively. 11,12 The results of this study indicate that WL in the 1st month after BIB placement and LAGB can be used as predictors for mid-term and possibly long-term WL.…”

“…Established predictors of weight loss (WL) after bariatric surgery include age, preoperative WL, initial body mass index (BMI), depression score, eating behavior and level of physical activity after surgery. [6][7][8][9][10][11][12][13][14] Only one study analyzed the influence of initial WL on long-term weight maintenance in patients treated with BIB. The authors concluded that a 5% WL after the first month predicted longterm outcome.…”

The Role of Cognitive Function in Postoperative Weight Loss Outcomes: 36-Month Follow-Up

“…A subset of patients enrolled in the Longitudinal Assessment of Bariatric Surgery (LABS) parent project underwent cognitive testing at preoperative baseline and serial postoperative timepoints; preoperative executive function and memory performance predicted 12-month postoperative BMI, and memory performance predicted 12-month percent excess weight loss. 5 Although this initial work did not elucidate how cognitive performance and weight loss outcomes are linked, it suggests a possible role of cognitive ability in postoperative adherence. Patients receive much of the necessary education regarding postoperative guidelines for lifestyle changes during the preoperative planning stage.…”

Psychosocial Issues After Bariatric Surgery

“…Some research suggests that psychological comorbidities serve as barriers to adherence. For example, within a retrospective study, researchers examined the medical records of 149 RYGB patients during the fi rst 4 years after surgery [ 36 ]. Results indicate that a diagnosis of depression is correlated with insuffi cient weight loss and poor dietary adherence.…”

“…As a result, a body of research has begun to examine the infl uence of cognitive defi cits on adherence. Within a sample of 84 patients, Spitznagel and colleagues [ 36 ] found that 16 % of preoperative patients evidenced clinically impaired performance on components of attention/ executive and verbal memory functioning. Such defi cits could lead to reduced adherence to postoperative lifestyle changes, including poor meal planning, diffi culties resisting foods, and trouble accurately recalling dietary and exercise guidelines.…”