Obesity has been described by the World Health Organization as a global epidemic. Obesity is defined as a body mass index (BMI) ≥30 kg/m² and it is estimated that almost a quarter of the population of England are obese.

Primary care physicians are familiar with the subsequent problems that can arise such as diabetes, cardiovascular disease and osteoarthritis to list but a few. At present the Quality and Outcomes Framework places little emphasis on obesity management and there are few options available in traditional models of primary care.

Patients will often self select for various commercial weight management programmes and in some areas these are available on the NHS. There is certainly evidence to support the notion of centrally funded commercial weight loss programmes, as a study in the Lancet ,1 reported in a clinical review in the November issue, has shown (Savill P. Are commercial weight loss programmes more effective than standard GP care? Practitioner 2011;255 (1745): 8-9).

Another option is for primary care teams to develop in-house obesity management programmes.

A study in the BMJ has investigated the effectiveness of several such interventions.² Lighten Up was a randomised controlled trial that studied 740 obese or overweight men and women identified from GP records in a primary care trust in Birmingham. Patients were aged ≥ 18 with a raised BMI recorded in their notes within the previous 15 months. The BMI threshold for inclusion differed according to ethnic group and comorbidities. It varied from ≥ 23 kg/m² for South Asians with comorbidities to ≥30 kg/m2 for Caucasian patients with no obesity-related comorbidity.

Patients were allocated to one of eight groups. Six weight loss programme groups of 12 weeks’ duration were compared with a minimal intervention group provided with 12 vouchers entitling them to free entrance to a local fitness centre. Three of the weight loss programmes were provided by commercial operators: Weight Watchers, Slimming World, and Rosemary Conley and three by the NHS: a dietetic-led group weight loss programme (Size Down) and two primary care programmes; either nurse or pharmacist led. The primary care programmes provided one to one support, with practitioners having attended a three-day training course on weight management led by experienced dieticians. The final study arm allowed patients to choose one of the six interventions. Patients in the comparator leisure centre group were given no individual advice or support on diet or physical activity.

The primary outcome was weight loss at 12 weeks. Secondary outcomes were weight loss at one year, self-reported physical activity, and percentage weight loss at 12 weeks and one year. Follow-up data were available for 658 (88.9%) participants at programme end and 522 (70.5%) at one year.

All programmes achieved significant weight loss from baseline with a range of 1.37 kg (general practice) to 4.43 kg (Weight Watchers). However, the commercial programmes achieved significantly greater weight loss than did the primary care programmes, mean difference 2.3 kg (1.3-3.4). At one year follow-up, all programmes except general practice and pharmacy provision resulted in significant weight loss. However, only the Weight Watchers group had significantly greater loss than the comparator group 2.5 kg (95% CI: 0.8-4.2).

The primary care programmes were the most expensive to provide and patients allocated to the choice arm had no better outcomes than those randomly allocated.

The authors suggest that the primary care programmes were not as successful because practitioners were less experienced and confident in weight management, the sessions were one to one rather than group and were more difficult to arrange compared with the permanently on-going weekly commercial sessions, and were therefore less well attended.

This study has shown that commercial weight management programmes are more effective and cheaper than one model of primary care based services. The authors went on to calculate that patients lost an average of 1.3 kg/m² with the most effective intervention which if maintained gives a crude cost per life year saved of £77. This would indicate that providing commercial weight loss programmes as an NHS funded service is a potentially cost-effective intervention. It is time for a more aggressive stance on obesity and this will require collaboration between public and private sectors to initiate and maintain the necessary behaviour change required to tackle this escalating problem.