Obesity Treatments for Adults Evaluated
A major evaluation of the various treatments which could be offered by the NHS for obesity has been conducted by a team of researchers led by the University of Aberdeen.
The £143,000 project, which was funded by the NHS Research and Development Health Technology Assessment Programme, has a wide range of findings, one of which is that exercise programmes and behaviour therapy contribute to improved long-term weight loss. However, these are not well established for the management of obesity in the NHS at all levels of care.
Dr Alison Avenell, Clinical Research Fellow with the Health Services Research Unit, at the University of Aberdeen, and first author of the study, Systematic Review of the Long-Term Effects and Economic Consequences of Treatments for Obesity and Implications for Health Improvement, said: "Consideration needs to be given to how exercise programmes and behaviour therapy of the type that we found used in trials to treat obesity in the USA could be implemented in the UK."
Professor Iain Broom, Consultant in Clinical Biochemistry Metabolic Medicine NHS Grampian and Research Professor at The Robert Gordon University, Aberdeen added: "It is clear that if the current rate of weight increase in the population continues then the NHS will, in the long-term, be dealing with a major epidemic of diabetes and the associated increase in cardiovascular disease."
The project set out to review the long-term effects of obesity treatments on body weight, risk factors for disease, and disease itself. The research encompassed three reviews that examined different aspects of obesity. The first reviewed obesity treatments in adults; the second examined long term effects of weight loss on morbidity and/or mortality; and the third looked at costs and outcomes of treatments. The review of obesity treatments incorporated data gathered from 84 trials into the treatment of obesity which took place mainly in Europe and America.
The review made a number of findings which included:
· Surgery was found to be the most effective treatment for extremely obese people (BMI>40kg/ m2) who are at risk of developing diabetes
· Adding certain weight reducing drugs available on the NHS to moderately obese people (BMI>28kg/m2) already dieting was beneficial
· Low fat diets were associated with the prevention of type 2 diabetes and improved control of hypertension
· Studies combining low-fat diets and exercise, with or without behaviour therapy, also improved control of hypertension and type 2 diabetes
· The addition of an exercise programme to diet was associated with improved weight loss and risk factors for at least one year. The addition of a behaviour therapy programme to diet was also associated with improved weight loss for at least one year.
· Women with obesity-related illnesses who had intentional weight loss, irrespective of the amount of weight lost, had a reduced risk of death, cardiovascular disease death (CVD), cancer and diabetes-related death. Weight loss appeared more beneficial if achieved within one year.
· Men with general illness who lost weight intentionally appeared to have a reduced risk of diabetes-related death, but there was no demonstrable effect on CVD mortality and cancer mortality
· Long-term weight loss has definite benefits in preventing the development of diabetes as well as improving the health status and risk of death for those already with diabetes
· Improvements in blood cholesterol levels are linearly associated with weight loss in the long-term
· While blood pressure is often improved with weight loss the relationship in the long-term is not as clear and requires further high quality research to investigate
· Targeting high-risk individuals with drug treatment, diet and exercise treatment, or surgery was likely to cost the NHS no more than many other NHS treatments
Dr Alison Avenell said: "Another interesting aspect we discovered centred on a review of trials which looked at low fat diets and weight reducing drugs.
"One group of people who were on a low fat diet were also given a dummy drug which they believed may have been a weight reducing drug. We compared them with a group who were also on a low fat diet but who weren't given any tablets. The group taking the dummy tablets lost less weight than those without tablets which gives the impression that people may not try so hard to lose weight with diet because they thought they were also taking weight reducing drugs."
Dr Avenell added: "More funding is needed to enable us to continue our research on the best way to manage obesity and the long-term benefits of such treatments."
* The study team comprised researchers from the University of Aberdeen (Health Services Research Unit, Department of Public Health and Health Economics Research Unit); NHS Grampian; The Robert Gordon University and Tayside University Hospitals NHS Trust. The University of St Andrews were also involved in the initial design of the study.
** This project was funded by the Health Technology Assessment Programme
(project number 99/02/02). The views and opinions expressed therein are those of the authors and do not
necessarily reflect those of the Department of Health.