This study explores the cost effectiveness of two weight loss programmes evaluated as part of a randomised controlled trial: (1) referral to a commercial provider (2) weight loss advice delivered through primary care channels, via GP or nurse. Participants (who were over 18 years old and had a BMI of 27-35 with at least one risk factor for an obesity-related condition) were recruited by their GP and randomised to either the intervention or comparison; the study was international, including participants from Australia, the UK and Germany. 772 patients were included; 440 completed the 12 month trial.
Participants’ weight was measured at the start of the trial and then at the following intervals: Months 2, 4, 6, 9 and 12. The researchers looked at the cost of treatment as well as associated costs such as travel to calculate the cost per kilogram lost for each intervention. Due to differences in costing, these values were calculated separately for each country. For the UK, the cost per kilogram lost was $90 for the commercially provided intervention and $151 for the primary care provided weight loss advice (delivered by a nurse in the UK intervention). Both interventions demonstrated weight loss but the loss was significantly greater in the group randomised to a commercial provider, across all 3 countries. The authors conclude that weight loss is more cost effective delivered via a commercial provider than through standard primary care.
There were some differences in relation to the frequency of visits – an average of 36 visits in 12 months for the commercial provider and 13.3 for primary care consultation. The authors acknowledge that it is unclear if the comparison (primary care led advice/consultations) is typical of routine care. The authors also recognise that the analysis would be more complete if data on utilisation of health services (e.g. unplanned admissions) or incidence of obesity-related conditions had been included. The trial did include measures of cholesterol and blood pressure, which are both important risk factors.
Given the high prevalence of obesity and the increasing cost pressures, commissioners will be interested in understanding which interventions offer cost effectiveness. The findings in this analysis seem consistent with another recent trial (Lighten Up), funded by NHS South Birmingham, which reported in the BMJ in 2011 (http://www.bmj.com/content/343/bmj.d6500).
It would be useful, however, to follow up patients at a later stage to understand if weight loss is sustained following completion of the programme. The authors make the valid point that some overweight and obese patients may not be able to afford the cost of enrolling in such a programme themselves and it would be interesting how many of the patients are able to either fund continued attendance themselves or if they can continue to sustain weight loss using what they have learned on the programme. It would also be useful to assess the optimal duration of weight loss programmes.
Fuller N R et al, A within-trial cost-effectiveness analysis of primary care referral to a commercial provider for weight loss treatment, relative to standard care—an international randomised controlled trial. International Journal of Obesity, 2013, 37(6): 828–834. Full text available at http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3679478/.
The abstract of the trial is available at http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(11)61344-5/abstract.
A further trial (WRAP – Weight Loss Referral for Adults in Primary Care) is underway, funded by the Medical Research Council; the trial is aiming to recruit 1200 participants and is expected to complete in 2016. This will randomise patients to either: (1) a 12 week programme via a commercial provider; (2) a 52 week programme via a commercial provider; or (3) a brief intervention. Outcome measures include: weight, waist circumference, body composition, and blood pressure at 3, 12 and 24 months; differences in biochemical measures (blood glucose, total cholesterol, HDL cholesterol, LDL cholesterol, and HbA1c) at 12 months; self-reported psychological factors, quality of life, and health care usage; and risk factors for diabetes and cardiovascular disease after 12 months. More information at http://www.controlled-trials.com/ISRCTN82857232.