Title: Development and feasibility of a behavioural intervention to increase physical activity in people who have undergone bariatric surgery.
Funder: Health Education England

Abstract: Overweight and obesity can have a negative impact on a person's mental and physical health; it can reduce life expectancy and effect employability and career progression. In the case of severe obesity, bariatric surgery successfully induces significant weight loss in a relatively short period of time. Often, patient motivations for surgery are to feel healthier, be slimmer, feel better and be more physically active. Research and audit data suggests that although increased levels of physical activity [PA] are an important part of the decision making process when deciding to have surgery, this does not always happen. Following surgery some patients do become more physically active but a significant proportion do not, and they may even reduce their activity levels further. Most patients do not achieve the recommended 150 minutes/week of moderate intensity PA. After having surgery patients find it easier to move, and may perceive that they are fitter but the evidence suggests that this is likely due to a significant reduction in body weight, which makes it easier to move, rather than an actual increase in cardiovascular fitness. There is evidence to suggest that the lack of increase in PA is a missed opportunity to capitalise on the benefits of bariatric surgery. An emerging body of research has identified that increased levels of PA can encourage the preservation of more metabolically active tissue with a preferential loss of fat mass. Other metabolic effects, such as improved insulin sensitivity has also been observed.Research suggests that interventions that are underpinned by a behaviour change theory are better able to facilitate the desired change such as improved levels of PA. The Behaviour Change Wheel [BCW] has been developed in response to the requirement for a robust theory that can be used to underpin interventions. While there is currently no published evidence for the use of the BCW to facilitate increase levels of PA in this patient population. When the BCW was reviewed against NICE obesity guidance there was an inter-rater agreement of 79%. There is a necessity to develop an intervention for this patient group that is acceptable and can be maintained over a prolonged period of time, which will fully optimise the outcome from bariatric surgery, and is underpinned by a solid theoretical base. Both the NIHR and NICE guidance have identified PA interventions for this patient group as a research priority, specifically in patients who have had bariatric surgery. The aims of this fellowship are to update the evidence base regarding PA interventions in this patient population and to fully comprehend the barriers and facilitators to PA in patients who have had surgery. The wider context from the perspective of service leads, commissioners and practitioners will also be explored. This information will be consolidated to model and develop an intervention with a PPI group that will be based on a sound behaviour change theory and will be tested in a feasibility study. The proposed research will benefit patients and the NHS as it has identified a gap in the current literature and a need for the development of a scientifically sound behaviour change intervention. If the intervention is successfully tested in a feasibility study, it can be assessed for effectiveness in a larger randomised controlled trial. This would be the first effective, behaviourally based intervention to facilitate increased levels of PA which is able to optimise the outcomes from bariatric surgery. This will result in significant improvements for patients in terms of quality of life, health and wellbeing with a reduction in utilisation of NHS services due to these improvements.

Lay abstract: Higher levels of physical activity [PA] reduce the risk of chronic illness and premature death- independent of weight. Unfortunately, some people struggle to be physically active; this may be due to their weight, size or weight related conditions. Sometimes, people who are very overweight choose to have surgery- such as a gastric bypass or sleeve gastrectomy- to help them lose weight. These operations are referred to as bariatric', weight loss' or metabolic' surgery (due to improvements that are seen, such as better blood sugar control). Often, the motivating factors for having surgery are to lose weight, feel healthier and be more physically active. Following surgery, clinical guidelines recommend that patients should be followed for up-to two years in a service with specialist doctors, dietitians and psychologists. During this time, patients should receive exercise counselling'. In practice this is done by the clinicians in the follow up service, and not by exercise specialists such as physiotherapists. Audit and research data shows that levels of PA remains low after surgery, suggesting that current practice may not be that effective. This was discussed with the patient and public involvement [PPI] groups who identified a number of different concerns; patients are unsure as to what they can do safely, how to progress their exercise or activity, they are not confident exercising in mainstream' environments and they feel they need personable expert input over and above the normal post-operative support. There is evidence that patients who are more active after surgery might have better long term outcomes; they might achieve a greater initial weight loss and reduce the risk of regain. It also improves other health markers, such as how well the body is able to use insulin- which is important for blood sugar control in diabetes. This fellowship will be used to develop an intervention that is acceptable to patients in helping them to increase their levels of PA after surgery and will have a lot of PPI to ensure it is realistic for this patient group. There will be two stages to this; firstly, development work will be done; the published research will be consulted to identify if there is any new evidence or programmes that are being used in practice. Patients who are currently under the specialist weight management service will be recruited to participate in focus groups where the barriers to PA will be discussed. Commissioners people who commission these types of services, service leads and clinicians will be interviewed to find out what it is important to them, from their perspective. I will then meet with the PPI group to see how all of this information might be used to develop an intervention which helps patients to change their behaviour and increase their levels of PA. The intervention will be developed using a behaviour change framework' it will be based on a theory of how people change their behaviour. The second phase will be to test the intervention in a feasibility study. This will identify if the intervention can be tested in a real patient population - the aims are to see if the required number of participants can be recruited, if they are happy to undertake the intervention as suggested by the development work and if they are happy to be randomised this means some patients will receive standard care as expected, whilst others will receive standard care plus the intervention. This does not always happen in feasibility studies such as this but it will be useful as it could identify if this will be acceptable to patients in a bigger, more expensive trial. The feasibility study will be evaluated to see if the intervention was delivered as designed-for example if it required participants to do something three times per week, were they able to do this, or was it unrealistic. The PPI group will be really important at this stage as they will have insight into why participants might have struggled with what was asked and how it might be managed in a future trial. ICA C-DRF 2017 Reference: ICA-CDRF-2017-03-008 Date submitted: 11/05/2017 Page 2 of 64 The PPI group will be asked to help disseminate the findings from this research via WLSInfo (a support group for people who have had or are considering surgery) and obesity specific conferences such as the Association for the Study of Obesity [ASO]. Local services, which provide post-operative follow-up care and clinical commissioning groups those who commission follow up services, will also be advised of the results of the study.

Research activity codes: 6.6 PSYCHOLOGICAL AND BEHAVIOURAL
Health categories: CANCER AND NEOPLASMS;CARDIOVASCULAR;METABOLIC AND ENDOCRINE;ORAL AND GASTROINTESTINAL;STROKE