From evidence and guidelines to implementation: development and feasibility testing the implementation of a brief behavioural intervention for weight loss

In the UK 27% of adults are living with obesity, causing an estimated 55,000 premature deaths and £6.2bn in healthcare costs. The Covid-19 pandemic brought additional risks of severe disease and death for people living with obesity. Within the NHS there are clinically proven effective and low-cost treatments for obesity that can be delivered through primary care. There is limited uptake of treatments, despite guidelines urging GPs to deliver these interventions and evidence showing their potential impact. National policy documents until 2020, had mentioned a potential role for GPs and treatment services for adults but fell short of outlining a coherent policy for them to intervene, and there wasn’t funding provision for services to refer into. There was therefore a gap between guidelines and policy.
This work described in this thesis aimed to close this gap and understand why primary care clinicians are not following guidelines; what is the prevalence of these weight management/loss interventions; is removing the barrier of routine weighing feasible; based on theory and real-world experience, how does policy change occur at the national level to influence frontline primary care obesity delivery. I used a mixed methods approach including: a cross-sectional analysis of survey data of patients’ reported experiences, a systematic review of qualitative studies, an ethnography and interview intervention development study of routine self-weighing, and a descriptive policy analysis.
To determine the prevalence, acceptability and impact of conversations about weight on patients’ weight loss intentions and actions, I did a cross-sectional analysis (Chapter 2). I found that most people with obesity reported trying to lose weight, and nearly half of people with obesity reported having received advice from their GP. Only 20% thought such advice was inappropriate. When people were given advice, only 1 in 20 were given specific advice or offered referral to a community weight loss service, which lead, on average, to a greater weight loss than self-directed efforts. This study suggests there is a lack of implementation of this evidence in practice, with many people with obesity who attend primary care reporting receiving general advice rather than specific referrals to services.
In the systematic review (Chapter 3) on primary care clinicians’ perspectives on discussing weight with patients with overweight and obesity, I found clinicians offer a variety of explanations as to why they do not offer support to their patients to lose weight, despite national guidelines urging them to do so. These related to the awkward and potentially stigmatising nature of the conversation, the lack of faith that patients will change, and the clinicians’ perceived lack of a clear intervention to offer. However, underlying all this is a sense that such conversations are not valued, especially by doctors, and that this relates to unspoken value systems in medicine that prize technological fixes over behavioural interventions. Financial incentives, training, and regular weighing were all reported as things that could potentially facilitate more frequent interventions.
In the following chapter (Chapter 4) I aimed to understand the feasibility of implementing routine self-weighing in clinical practice, using ethnographic methods, interviews and focus groups. I observed the effect routine weighing has on patient flow and the overall acceptability of the intervention to patients and staff. Routine self-weighing had never been studied, to my knowledge, in the UK before. This study showed that whilst implementing routine self-weighing was technically feasible and acceptable to patients, the new practice struggled to get wide buy-in from all patients and staff. Cited barriers for this activity included lack of responsibility to deal with obesity and lack of connected services. Wider analytical themes were that patients or staff didn’t see value in the new practice so did not prioritise doing it.
In the following chapter (Chapter 5) I aimed to contextualise the subsequent national policy developments in the 2020 obesity strategy and to understand how the policy theory relates to these developments. This strategy included a significant change in direction in primary care treatment policies, which pre-2020 had only urged clinicians to intervene without outlining a coherent policy for them to do so (i.e. without training, incentives, or funding for services to refer into). In the year after this was implemented, over 350,000 referrals to weight management services were recorded. This chapter looks to understand why this change happened by applying policy theory to practice. Broadly, I found theories could be split into ‘stage’ theories which outline policy as a carefully planned sequential and rational process; and ‘power’ theories, which say that policy-making is far more about power dynamics of different actors and not a sequential or rational process. I found that the case study had some similarities with the stage theories: there were necessary preconditions, such as measurement and recognition, which gave the item the salience and support to be a legitimate issue for the Government to be able to talk about and act upon. However, these ‘stages’ and rational theories only explain so much. The powers of the then Prime Minister in terms of appointments, patronage, and influence, were crucial factors in making this policy a reality. Kingdon’s ‘window of opportunity’ theory, helped explain why obesity entered the national debate in mid-2020 due to the Covid-19 pandemic, and the then Prime Minister’s own personal experience with Covid-19 and his weight. The longevity and impact of the policy was however limited, when all the funding was cut in the spring of 2022. This emphasises the unstable nature of power and resulting policy from this power, which is vulnerable to changes in the level of political support for the individual driving through the change.
The combination of my studies has helped to further the understanding of GP interventions in primary care, namely that patients with obesity who are trying to lose weight report rarely receiving specific referrals to effective treatment services. Meanwhile, many GPs seemed not to prioritise delivering such interventions, citing reasons such as it not being their job, or lack of time. They also helped contextualise the policy developments from within government and showed the difficulty in getting sustained action on prevention policies, due to short-term funding pressures for more acute health services. Lack of weight data was cited as a potential facilitator and could be added to routine clinical practice, but would need to be part of a broader system change of interventions and would require further testing, to find the most efficient and scalable method to make it part of clinical workflows. My findings have implications for weight management guidelines, namely that on their own in their current form, the guidelines are not sufficient to drive necessary change in GP behaviour. In the conclusion I suggest a ‘way forward’ to help obesity policies become prioritised and more long-term. This would be achieved by cross-party commitments linked to significant long- term investments (mapped to long-term reductions in the costs of obesity related diseases).

Advisor: Aveyard, P
Bell, J
Hobbs, R
Ziebland, S
Tudor, K