A randomised controlled trial to test the clinical and cost-effectiveness of primary care referral to a commercial weight loss provider.

Overweight and obesity is a serious public health issue due to its high prevalence and association with illnesses, such as Type II diabetes, heart disease and cancer. Early treatment and prevention are important if we are to reduce the health problems associated with excess weight, but there are few treatments available through the National Health Service (NHS) and those that are available can be very costly when we consider the number of people requiring treatment. It is in the interests of the NHS to offer (cost-effective) weight loss treatment options, as they spend £4.2 billion each year on treating illness related to overweight and obesity. The cost to the wider community is estimated at £16 billion. This study seeks to examine one of the treatment options currently available on the NHS - referral to a commercial weight loss treatment provider - and to establish whether this treatment option is cost-effective in helping people to lose weight and keep it off. Previous research has shown that referring a patient for 12 sessions with a commercial weight loss provider can produce an amount of weight loss which has significant health benefits. These referral packages are offered to the NHS at a discounted price, however no studies have formally evaluated the cost-effectiveness of this approach. This study will examine whether the money spent on treatment is worthwhile when we consider the effect of improved health for patients and also potential cost savings on treatments for weight-related illness. But weight regain is common after weight loss treatment stops and it may be that 12 weeks is not long enough to develop long term changes in behaviour. It is not hard to imagine that a 12 month referral could lead to greater weight loss and more long term changes than a 12 week programme, and that this could mean less weight regain. However, the likely increased effect will come at a higher cost, leaving the question 'What is the more cost-effective option?'. This is precisely what this study seeks to examine. We also want to uderstand more about the patient experience of weight loss treatment. Previous research has shown that many adults with overweight and obesity do not consider this to be a medical problem and this may influence their attitudes to receiving treatment through the NHS. By improving our understanding of attitudes and experience of treatment, we can improve the way weight management is provided by the NHS. In our trial, 1200 adults with overweight and obesity will be identified by their GP and recruited by the research team. The research team will randomly assign participants to one of three treatment groups - a 12 session referral to a commercial provider, a 12 month referral to a commercial provider, or a 'brief intervention' (standard information about how to lose weight and weighing at follow up). We will follow participants up at 3 months, 12 months and 24 months (1 year after treatment has finished) to compare the amount of weight lost by participants in each group. We will also look at how many participants in each group lose an amount of weight that is associated with significant health improvements. We will use this and other data collected during the trial to examine which treatment option offers the best value for money. This will be examined over the short term (the duration of the trial) and the longer term, using long term modelling of anticipated health changes and associated costs. We will also interview a subset of participants to gain a more holistic view of the patient experience and to explore their attitudes to weight loss treatment and NHS-commercial partnerships. This research will provide important information to GPs and NHS treatment commissioners about which treatment option is most effective and which offers best value for money. Trial results and findings from interviews will help inform future decisions about NHS-commercial partnership