Obesity is undoubtedly an important and increasing problem in developed countries. The problem is clearly set out in the National Audit Office (NAO) report1 and elegantly summarised by Dr Ian Campbell in the March issue of Guidelines in Practice (Vol. 4(3): 69). A recent BMJ editorial addresses the increasing prevalence of type 2 diabetes in children associated with increased obesity.2
I readily acknowledge the problem but am worried by the proposed medical management in the NAO report and the National Obesity Forum (NOF) guidelines.
For guidelines to be a success they must have a sound evidence base, and must not advise referral for investigations or treatments that are unobtainable. The NOF guidelines fail both these tests. They give no evidence to support the view that intensive support from the primary healthcare team improves outcomes for obese patients.
Many older studies show a failure of diet to help obesity.3 The closest approximations to recent evidence that I know would be the Oxcheck study and British Family Heart Study.4,5 In these studies, obesity was not the prime concern, but intensive advice on diet and exercise was given and BMI was monitored as part of the attempt to reduce overall cardiovascular risk. Over an extended interval, the changes were modest and achieved at great cost.
One of our practice nurses ran a healthy eating group for some years which she diligently audited for long-term outcome. Her results confirmed modest benefits in sustained weight loss for high levels of support.
The guidelines' second-line advice includes: orlistat; sibutramine, which is currently not available in the UK; unspecified 'alternative treatments'; and referral to secondary care for surgery that is not readily available outside major centres.
Dr Campbell states that 'obesity is predominantly a primary care problem' and implies that prevalence of obesity continues to rise because of lack of guidelines to care for it. The NAO report supports this approach with particular reference to the practice nurse who ' has more time to do follow-up'. Our nurses now run baby clinics, teenage clinics, diabetes clinics, asthma clinics, IHD clinics and perform nursing duties.
We are in danger of medicalising a multifactorial problem without evidence that we can help improve the outcome.4 The list of causes of obesity in the guidelines, with its rare and largely untreatable categories, does not include the most common causes of iatrogenic weight gain that I deal with, namely sulphonylurea, insulin and lithium therapy.
All GPs are familiar with the disappointment in the eyes of an overweight patient whose thyroid tests are normal, and the extended consultations where suggestions for lifestyle changes are blocked. Equally, we are aware of the massive changes brought about by a motivating event, such as a heart attack, often with no medical input.
I want to feel that the strategies I offer will have a good chance of helping. Both the NAO report and the NOF imply that if we work harder at improving existing interventions and support we will improve outcomes, yet there is no evidence to support this contention. Perhaps we should be looking for new ways to tackle obesity.
Dr Matthew Lockyer, GP, Suffolk
- National Audit Office. Tackling Obesity in England. London: The Stationery Office, 2001.
- Fagot-Campagna A, Venkat Narayan KM, Imperatore G. Type 2 diabetes in children. Br Med J 2001; 322: 377-8.
- Wooley CS, Garner DM. Controversies in management. Dietary treatments for obesity are ineffective. Br Med J 1994; 309: 655-6.
- Imperial Cancer Research Fund Oxcheck Study Group. Br Med J 1995; 310: 1099-104.
- Wood DA, Kinmonth AL, Davies GA et al Randomised controlled trial evaluating cardiovascular screening and intervention in general practice: principal results of the British Family Heart Study. Br Med J 1994; 308: 313-20.