Comparison of range of commercial or primary care led weight reduction programmes with minimal intervention control for weight loss in obesity


Interventions Weight loss programmes of 12 weeks' duration: Weight Watchers; Slimming World; Rosemary Conley; group based, dietetics led programme; general practice one to one counselling; pharmacy led one to one counselling; choice of any of the six programmes. The comparator group was provided with 12 vouchers enabling free entrance to a local leisure (fitness) centre.Main outcome measures The primary outcome was weight loss at programme end (12 weeks). Secondary outcomes were weight loss at one year, self reported physical activity, and percentage weight loss at programme end and one year.Results 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 to programme end (range 1.37 kg (general practice) to 4.43 kg (Weight Watchers)), and all except general practice and pharmacy provision resulted in significant weight loss at one year. At one year, only the Weight Watchers group had significantly greater weight loss than did the comparator group (2.5 (95% confidence interval 0.8 to 4.2) kg greater loss,). The commercial programmes achieved significantly greater weight loss than did the primary care programmes at programme end (mean difference 2.3 (1.3 to 3.4) kg). The primary care programmes were the most costly to provide. Participants allocated to the choice arm did not have better outcomes than those randomly allocated to a programme. One widely available option is a commercial weight management programme. In some areas, the English National Health Service offers these services free to patients, and some evidence supports the effectiveness of such provision. A randomised trial of 400 overweight and obese adults in the United States showed that people offered two years' free use of a commercial weight management service lost 2.0 kg, whereas those offered two consultations with a dietitian and self help resources lost 0.2 kg at the end of two years.5 (These figures were calculated according to intention to treat, using baseline observation carried forward for missing data. Unless otherwise indicated, all figures quoted in this paper use this convention.) Another trial comparing a very similar control group with a different commercially available intervention, which supplied pre packaged "diet" foods,6 had similar conclusions, with weight loss at one year of 6.6 kg versus 0.7 kg. More recently, a trial offering six months' free use of commercial weight loss programmes led to weight loss of 5 6 kg compared with 0.6 kg in the control group, who were asked not to try to control their weight.7 Thus good evidence shows that commercial weight management services can be effective, but all existing trials investigated the effectiveness of prolonged treatment programmes that are not available in the English NHS nor in many other health systems.An alternative, potentially widely available, management option for obesity is for primary care teams to treat their obese patients themselves. A well known primary care programme, the Counterweight programme, has shown promising results in an uncontrolled trial.8 9 10 However, a cluster randomised trial showed that weight loss among obese patients offered treatment by primary care teams who had received well planned training in obesity management (4.5 hours' total training) was less than 1 kg and was similar to the weight loss seen in control practices.11 Therefore, insufficient evidence exists for the effectiveness of obesity management in primary care.We therefore investigated the effectiveness of several pragmatic interventions in primary care patients recruited in the English NHS. These included more modest entitlement to free commercial weight loss management programmes, primary care management, and a minimal intervention control.MethodsThe protocol for the study, describing the study design, is available online.12 Lighten Up was a randomised controlled trial with patients individually allocated to one of eight study groups. We compared six weight loss programmes with a minimal intervention comparator group provided with 12 vouchers enabling free entrance to a local leisure (fitness) centre. Three weight loss programmes were provided by commercial operators: Weight Watchers, Slimming World, and Rosemary Conley. Three were provided by the NHS: a group weight loss programme (Size Down) and two primary care programmes nurse led one to one support in general practice and one to one support by a pharmacist. The final study arm allowed for participants to choose one of the six interventions.PopulationEligible participants were registered with general practices in South Birmingham Primary Care Trust, were aged at least 18 years, and had a raised body mass index recorded in their primary care notes within the previous 15 months. The body mass index threshold for invitation was that which makes them eligible for primary care obesity management services in the NHS and varied according to ethnic group and the presence or absence of comorbidities (box 1). The threshold for invitation for people with no obesity related comorbidity was a body mass index of 30 or above. For people of South Asian ethnicity, this threshold was lower. The general practitioner had to confirm that the patient had no medical contraindications for any of the intervention programmes before a letter of invitation was sent. We excluded patients if they were unable to understand English or were pregnant. Seventeen practices took part.Box 1: Criteria for invitation to weight loss programmesWhite Europeans and all ethnic groups apart from South Asians with no comorbidities: BMI 30White Europeans and all ethnic groups apart from South Asians with comorbidities: BMI 28South Asians with no comorbidities: BMI 25South Asians with comorbidities: BMI 23Recruitment took place from January to May 2009. Eligible patients were invited to participate in the trial by a standard letter from their general practitioner, which included the patients' information leaflet and a free telephone number for a call centre managing the recruitment and randomisation. The nurses at the call centre provided more information to patients about the trial, collected baseline information, took verbal consent, and randomised patients to the trial arms. The nurses then booked participants into their first treatment session and sent confirmation, along with verification of consent and information on how to withdraw from the trial if they changed their minds. Participants allocated to the general practice, pharmacy, or minimal intervention (comparator) groups were sent details about how to arrange their first session.We randomised participants from practices with personnel trained to provide the practice based weight management programme (n=7) to all eight arms with a block size of 35, whereas we randomised people from other practices (n=10) to one of seven groups (excluding general practice) in a block [url=http://www.dolphinsmalls.com/authentic_ndamukong_suh_miami_dolphins_jersey.... Suh Jersey size of 13. An independent statistician prepared two separate randomisation sequences, and, to ensure blinding, the allocations were placed in opaque, consecutively numbered envelopes, which the call centre staff used in order. The block sizes were determined to achieve one to one randomisation across groups, except for the two primary care arms, for which spaces were limited and allocation was in a ratio of 1 to 0.7 compared with the other groups.InterventionsThe participants allocated to the commercial operators Weight Watchers, Slimming World, and Rosemary Conley had a choice of locations and times for the programme.13 14 15 Participants were provided with vouchers that exempted them from paying for 12 consecutive weeks of the programmes. Each programme was provided in accordance with the respective organisation's guidance and ran continuously, with no set start date; the group leaders were trained by the respective organisations. The trial participants attended alongside people who paid to attend the programmes.The Size Down Programme is an NHS group based programme led by food advisers recruited from the local community and trained by the dietetics department; sessions took place in various community venues. All members of the group started together and followed a prescribed course of six sessions, with follow up weighing sessions at nine and 12 weeks. Participants randomised to the general practice or pharmacy arms attended 12 one to one sessions in the general practice or pharmacy. Appointments were made at a time mutually convenient to the participant and the nurse/pharmacist. Staff delivering these programmes had attended a three day training course on weight management in adults delivered by dietitians experienced in the management of obesity. This included key messages on diet and physical activity, doing a behavioural assessment, goal setting, plans for change, dealing with resistance, enhancing motivation, and weight maintenance. It included both practical tasks and informational components. Participants were not given an appointment to attend and were given no individual advice or support on diet or physical activity. Box 2 gives further details of the interventions, and fuller details are online.12Box 2: Brief description of interventionsWeight Watchers is group based, and the participant was able to join at any time. One to one support is available for new members and during weighing. This is followed by [url=http://www.dolphinsmalls.com/authentic_kenny_stills_miami_dolphins_jersey.h... Kenny Stills Jersey a group talk from the leader, with discussion. Meetings took place in community venues and lasted one hour. Core programme material delivered over five weeks included a food points system (based on age, sex, height, weight, and activity), beating hunger, taking more physical activity, eating out, and keeping motivated. Other sessions delivered to the whole group covered recipes, health and nutrition, and keeping active. The plan aims for 500 kcal (2.09 MJ) deficit/day, leading to 0.5 1.0 kg weight loss a week. Physical activity is encouraged; the objective is to gradually build up to 10000 steps daily. Predominant strategies used to change behaviour included stages of change, food and activity diaries, goal setting, and evaluation of progress. Rewards are given for every 3.2 kg (7 lb) lost and for loss of 5% and 10% of body weight.Slimming World is group based, and the participant was able to join at any time. Meetings took place in community venues and lasted 90 minutes. Also included is access to [url=http://www.dolphinsmalls.com/authentic_kenny_stills_miami_dolphins_jersey.h... Stills Dolphins Jersey a website, magazines, and one to one telephone support from a consultant or other members. Members are encouraged to eat mainly foods with low energy density to achieve satiety, plus some extras rich in calcium and fibre, with controlled amounts of high energy dense foods. Weight loss goals are set by the individual. Physical activity is encouraged, with gradual build up to 30 minutes of moderately intense activity five days a week. The theoretical background is based on transactional analysis and motivational interviewing. Predominant behaviour change strategies used included weekly weighing; group support; and group praise for weight loss, new decisions, and continued commitment even in the absence of weight loss. Awards are given for 3.2 kg (7 lbs) lost and loss of 10% of body weight. Individual support, if needed, uses self monitoring of food and emotions, for and against evaluations, visualisation techniques, and personal eating plans.Rosemary Conley is group based, and the participant was able to join at any time. Meetings took place in community venues and lasted 90 minutes. One to one support is offered during weighing and to establish a calorie allowance. Additional support is available by email and telephone. Goals are staged: either 1 1.5 kg/week with a goal of 6.35 kg (1 stone) loss or 0.5 1 kg/week with an initial goal of 3.2 kg (7 lb). Sessions include a 45 minute optional exercise class. Extra exercise sessions may be offered for an additional fee. The theoretical background is based on role modelling and group support and uses visualisation and reframing to support behavioural change. Predominant behaviour change strategies used include rewards for slimmers who maintain or lose weight, slimmer of the week, and certificates for 3.2 kg and 6.35 kg milestones.The Size Down Programme was an NHS group based programme run in community venues by support workers trained by the dietetics service. This provided six weekly two hour sessions, with follow up sessions at nine and 12 weeks. All participants joined together in week one of the programme. Its particular focus was on long term changes in patterns of eating behaviour, achieving a balanced diet, and increasing physical activity in daily life, and it used an interactive style. Topics covered included managing behaviour around food and prevention of relapse, the eatwell plate, nutritional information, planning strategies to deal with lapses into previous dietary behaviours, interactive visual aids to show the fat and sugar content of foods, and adaptation of recipes. The theoretical background was based on the cycle of change (Prochaska and Di Clemente). The benefits of physical activity, setting goals, and finding activities to fit into life were discussed. Predominant behaviour change strategies used included goal setting, stages of change, and self monitoring with a food diary.