Psychosocial Predictors of Work Ability in Morbidly Obese Patients: Results of a Cross-Sectional Study in the Context of Bariatric Surgery

Introduction: The long-term impact and cost-effectiveness of weight management interventions depends on post-treatment weight maintenance. There is growing evidence that interventions based on third-wave cognitive behavioural therapy (3wCBT), specifically Acceptance and Commitment Therapy (ACT), could improve long-term weight management. However these interventions are typically delivered face-to-face by clinical psychologists, which limits their scalability. We used an evidence-, theory-and person-based approach to develop an ACT-based intervention for weight-loss maintenance that uses digital technology and non-specialists to minimise resources needed for delivery at scale. Methods: Intervention development was guided by the Medical Research Council framework for the development of complex interventions in healthcare, Intervention Mapping Protocol, and the person-based approach for enhancing the acceptability and feasibility of interventions. Two phases of work were conducted: phase one consisted of collating and analysing existing and new primary evidence, and phase two consisted of theoretical modelling and intervention development, including development of guiding principles, a logic model and the intervention design and content. Target user and stakeholder panels were established to inform each phase of development. Results: This process resulted in a guided self-help intervention called SWiM (Supporting Weight Management). SWiM is a 4-month programme, consisting of weekly web-based sessions for 13 consecutive weeks, followed by a 4-week break for participants to reflect and practice their new skills, and a final session at week 17. Each session consists of psycho-educational content, reflective exercises, and behavioural experiments. SWiM includes specific sessions on key determinants of weightloss maintenance, including developing skills to identify and manage high-risk situations for lapses, creating new helpful habits, breaking old unhelpful habits, and learning to manage interpersonal relationships and their impact on weight-management. A trained, non-specialist coach supports participants through the programme with four scheduled 30-minute telephone calls and three further optional calls, which are guided by scripts. Conclusions: This comprehensive and iterative approach facilitated the development of an intervention that is based on scientific theory and evidence to support people with weight loss maintenance, and is grounded in the experiences of the target users and the context in which the intervention is intended to be delivered. The development of SWiM is prudent given the novel coronavirus pandemic, and the increased need for remote delivery of weight management interventions. The intervention will be refined based on findings of a planned pilot randomised controlled trial.