Abstract / Summary
Recurrent weight gain after metabolic and bariatric surgery (MBS) can erode long-term benefit, and many proposed correlates are modifiable.We conducted a systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement.PubMed/Medical Literature Analysis and Retrieval System Online (MEDLINE), Embase, Web of Science, Scopus, and Google Scholar were searched, with citation searching, for studies of adults relating postoperative behavioral or psychological exposures to weight regain after a postoperative reference point.The databases yielded 1212 records and other sources yielded 12 (108 full texts assessed; 12 studies included); citation searching identified seven further studies, giving 19 studies (18 independent cohorts; 36 to 1278 participants).Risk of bias was appraised with Newcastle-Ottawa and Joanna Briggs Institute tools, and confidence in the evidence was rated with a structured approach informed by Grading of Recommendations Assessment, Development and Evaluation (GRADE) domains.Random-effects metaanalysis (restricted maximum likelihood, with Hartung-Knapp confidence intervals as the principal inference) was performed when at least two independent studies reported the same construct, instrument family, and metric for comparable outcomes; other evidence was synthesized narratively.Two exposures met these criteria, each pooled from the same two studies (139 participants).For eating disinhibition, the pooled standardized mean difference was 0.81, but the Hartung-Knapp 95% confidence interval (CI) included no difference (-0.40 to 2.02; I² = 0%); for depressive symptoms, it was 0.11 (Hartung-Knapp 95% CI -0.93 to 1.14; I² = 0%).In the narrative synthesis, binge eating was associated with more regain in the largest prospective cohort, and four smaller studies agreed in direction.Lower activity levels or greater sedentary behavior were associated with greater regain in most reports, although one prospective accelerometry study found no association.Confidence was low or very low, and reverse causation could not be excluded.The review was not registered.These findings identify domains that may warrant consideration in postoperative assessment, but whether screening or modification reduces recurrent weight gain remains uncertain.