Single-centre, non-randomised clinical trial at a tertiary care centre to investigate 1-year changes in social experiences and biomarkers of well-being after bariatric surgery in individuals with severe obesity: protocol for the Bariatric Surgery and Social Experiences (BaSES) study.

introductionObesity is linked to increased loneliness and less enjoyment of social interactions. While bariatric surgery is the most effective treatment targeting severe obesity, there is limited understanding as to whether patients experience social interactions differently after surgery. The Bariatric Surgery and Social Experiences study is designed to assess potential changes in how much patients enjoy and engage in daily social interactions 1 year after Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). METHODS AND ANALYSIS: Single-centre, non-randomised clinical trial carried out at the Department of Endocrinology, Obesity and Nutrition at Vestfold Hospital Trust, Norway. Eligible patients (N=113) will undergo either RYGB, SG or single anastomosis sleeve ileal (SASI) bypass. The primary outcome measure is change in the social experience score (assessed with a questionnaire) from a presurgery to a follow-up assessment 1 year after RYGB and SG. The respective changes after SASI bypass will be assessed and considered exploratory. ETHICS AND DISSEMINATION: The most recent protocol version of this study was reviewed and approved by the Regional Committee for Medical Research Ethics South East Norway (REK sør-øst A) on 29 August 2022 (ref: 238406). The results will be disseminated to academic and health professional audiences and the public via publications in international peer-reviewed journals and conferences. TRIAL REGISTRATION NUMBER: NCT05207917.