Weight management

If being overweight increases the risk of mortality, intentional weight loss ought to reduce mortality and morbidity. There is no definitive study of this effect, but several studies suggest that intentional weight loss reduces risk factors other than obesity.(1,2)

One major difference between obesity and hypertension is that individuals can tell from their appearance whether they are obese. The stigma of obesity is also evident in the attitudes of the general public and healthcare professionals. (1)

The negative psychological consequences of obesity are revealed by educational status, marital status, and income levels of adolescents who remain overweight to adult life. These effects are more evident in females than males. The stigma of obesity means that any effective treatment will be used for cosmetic as well as medical reasons(1).

Non-drug interventions

Dietary interventions

An appropriate diet allied with physical activity and non-smoking is to be encouraged to improve general health as well as weight control. A diet high in vegetables, fruit and fish with modest amounts of fats, together with limited intakes of food and drinks rich in fats, salts and sugars is optimal.(2)
A weight reducing dietary regime should initially provide a 500-600kcal per day energy deficit, based on an estimated initial maintenance energy, and contain approximately 30% calories as fat. It should be coupled with a modest increase in physical activity(2,3)
Fibre supplements have been found to be more effective than placebo at in-creasing weight loss when given in conjunction with a 1200-1600 keal/day diet. However this does not appear to lead to a greater mean weight loss than a low fibre/low calorie diet.(4)
Eating and drinking are essential for good health and play an important part in everyday life. Eating should be enjoyable. Losing weight should make no difference to this.
Being overweight is the result of eating more energy (calories) that a body needs so to lose weight you need to take in less energy.
Energy (calories) comes from fats/oils, sugar and starches and protein. Virtually all foods contain energy. Some have very little such as vegetables, salads and fruit - others have a lot e.g. fatty/fried foods and sugary foods.
Try not to think of your patients "going on a diet" - the changes needed to lose weight are likely to be long term. They need to try to accept that they need to eat a different balance/choice of foods if you are going to lose weight. You do not have to cut out your favourite foods.
If they regularly eat fatty and sugary foods e.g. crisps, chips, biscuits, pastry, chocolate, sweets, cakes, etc. then advise them to keep them as occasional rather than every day foods.

Suggested Advice:

It is important that they eat regular meals/snacks at least 3 ~a day.
Keep clear in their mind the benefits to their body of losing weight.
Try planning meals ahead so that they are interesting, varied and satisfying.
Learn to eat slowly - you can feel 'hall up' more quickly.
Try a smaller plate - makes portions look larger!
If they feel hungry - suggest a sugar-free drink or nibble raw vegetables/fruit.
Advise them not to give up if they feel they have overindulged or had a bad day. The extra energy (calories) from this will not make you put all the weight back on - it is what you do every day which matters.
Regular exercise is important, if they can manage it - taken in an addition to usual daily activity.
Gradual weight loss is advised - it is better in the long run, to lose weight slowly and steadily.
DO NOT weigh themselves more than once a week.
Set a realistic target for weight loss - remember any weight lost will be a health benefit.

Very low calorie diets (VLCD), arc liquid meals providing about 800kcals per day. They should only be used after attempts at conventional restriction of normal diets have failed. (2, 3). This approach to weight reduction should not be used in primary care without appropriate dietician advice.

Community referral to dietitian

It should be considered appropriate to make a referral to a dietician for the following patients:

Anyone with BMI greater than 30
BMI less than 30 but with any of the additional risk factors present:
1. Hypertension
2. Hyperlipidaemia
3. Diabetes
4. Distribution of fat is central
5. Awaiting orthopaedic intervention
6. Rheumatology/arthritis sufferers
7. Gynaecological referrals

Exercise Interventions

Physical activity is a useful adjunct to dietary restriction for weight loss and seems to be very important for successful long-term maintenance of a healthy weight. Furthermore inactivity is a primary risk factor for mortality and morbidity and should be targeted in its own right, but the benefits are potentially greater for obese people. Activity also carries many additional benefits including improved functioning capacity and psychological well being.

Physical activity should be included as an essential part of obesity treatment with patients supported in their eftbrts to steadily build up a daily routine including moderately intense exercise such as brisk walking and reduce time spent in sedentary pursuits.
For some obese individuals substantial programme support will be required, particularly in the early stages. Such programmes could be designed and offered in primary or secondary care settings leisure and community centres or commercial and corporate settings.

Physical activity recommendations for obese patients are as follows:

Build up slowly to walking for 30 minutes per day on at least 5 days per week.
Walk at a pace that achieves mild breathlessness. Two 15-minute sessions are almost as good.
Eventually consider extending some sessions to 40 minutes or more to encourage fat burning.
Increase the amount of activity in the daily routine such as housework or shopping.
Reduce the amount of time spent on activities that involve sitting down such as watching television.
Consider resistance training to conserve muscle mass and maintain resting metabolic rate.
Try to find ways to make exercise enjoyable.

Behavioural programmes

Behaviour modification is widely used and incorporated in to many self help groups. It encourages individuals to take responsibility for their lifestyle by the development of programmes, which make the individual aware of their lifestyle behaviour, unlearning this pattern and replacing it with a healthier version (2,4) Overall there is little evidence their behavioural treatments by themselves are effective(5)

Cue avoidance (situations that provide the temptation to over-eat) may be more effective than cognitive approaches in role-play to rehearse resisting overeating or social pressure. Cognitive therapy may have more impact when of longer duration.t51

Standard behavioural therapy combined with the provision of meal plans and grocery lists to obese women produced significantly greater weight loss than a standard behavioural therapy alone.(5)

Effects of behaviour modification

The aim of behaviour modification is to produce a lifelong habit change. The interventions focus on managing environmental factors that control behaviour, and may include guidance on meal frequency, pace of eating, avoiding situations that provide the temptation to overeat, and separation of eating from other activities. Most studies report that patients tend to achieve weight loss within 3-6 months, but commonly regain in the long term.(4)

Many people attend slimming clubs. These provide valuable support through the presence of a group, and often result in large amounts of weight being lost initially, but there are no published data on their long-term efficacy.(4)

Patients should be encouraged to weigh themselves once a week. Eating and activity patterns should be reviewed and ideally advice given for the whole family, not just the person who is overweight (4).

People who maintain weight loss are characterised by eating a low fat/low calorie diet, weighing themselves at least once a week and monitoring their food intake.(4)

Criteria for referral to mental health services

The tiered approach to mental health problems may be used to match patients to the appropriate source of help. At tier I the person's problems are seen as simple rather than complex, symptoms are mild to moderate, and there is minimal impact on other important areas of life (e.g. work, relationship, family). An example might be a person who over-eats in response to stress, but is otherwise functioning well.

Tier 1 clients can be helped by members of the primary health care team, perhaps using self-help materials. Referral to a dietitian may be appropriate.

Tier 2 problems are moderate mental health problems which are not likely to improve without specialist therapy, but which do not prevent day to day coping. An example might be a person with bulimia nervosa, who does not have any other mental health problems, and is still able to work and maintain relationships. A client like this may be referred to a primary care CPN, acute CPN, or psychologist for a short-term focused psychological treatment, most likely to be cognitive-behavioural therapy.

Tier 3 problems are complex, most likely long-standing and recurrent, with significant impairment of quality of life. An example might be a person who has suffered from episodes of bulimia nervosa, anorexia nervosa and depression over many years, and is unable to work or to sustain relationships. In this ease, a specialist assessment from a clinical psychologist or clinical nurse specialist is required. If psychological treatment is appropriate, medium to long term therapy will be offered (usually lasting between 6 and 1 8 months).

Tier 4 refers to people with severe mental health problems with significant impairment of functioning. An example might be a person who has longstanding severe personality difficulties, binge-eats and self-harms in response to negative emotional states, and may require admission to hospital. In this case assessment may be by the in-patient multi-disciplinary team, who may refer on for psychological therapy.

Thus direct referrals for psychological therapy are most often appropriate for tier 3 and tier 2 patients. GPs in the Urban Sector (Wansbeck, Castle Morpeth and Blyth Valley) should refer to the Department of Psychological Therapies and Research, West Farm House, 1-2 West Farm Court, Cramlington, NE23 lAX; GPs in the Rural Sector (Tynedale, Alnwick and Berwiek) may address referrals to the Psychology Service at the Fairnington Centre, Hexham. Psychological therapy services are provided locally in Cramlington, Ashington, Bedlington, Morpeth, Alnwick, Berwick and Hexham.

Cognitive behavioural therapy for clients with eating and weight problems

Most clients referred to secondary mental health services for psychological therapy for eating and weight problems are likely to receive cognitive behavioural therapy, although a small number may be offered an alternative intervention such as psychodynamic psychotherapy.

Following a thorough psychological assessment, a formulation of how the person came to develop eating and weight problems and how the problems are maintained will be derived, and a treatment plan will be agreed with the client. Weight loss goals would not be agreed unless there were medical indications for this. However, the goals of achieving regular healthy eating if achieved would generally lead to weight loss. Strategies would be developed to assist the person in maintaining changes in dietary intake and lifestyle. The most important part of treatment, however is to address the underlying difficulties from which the eating problems arose such as tow self esteem and negative beliefs about oneself and one's value to others. Cognitive behavioural treatment is likely to consist of weekly sessions over a period of four to six months, after which the frequency of sessions may be decreased. A total of between ten and twenty to thirty appointments are likely to be offered.

Surgical Interventions

Weight loss associated with surgical interventions is greater and more sustained than that achieved by non-surgical methods.(2)

The RVI metabolic clinic (appendix A) currently provides surgical intervention assessments.

The local service provided by the RVI is currently under review.

Surgical intervention is normally considered only in people with morbid obesity (>40kg/in2, because it is associated with a higher risk of premature death) and when less invasive methods of weight loss have failed.(5)

In general the weight loss associated with surgical interventions is greater and more sustained than that achieved by non-surgical methods. Surgery however, is associated with complications such as revision of the initial surgery, vitamin and mineral deficiencies, associated mortality, feeling of fullness, dizziness and nausea and a desire to lie down after eating (dumping syndrome).(4'5)

Surgery is the only intervention that really guarantees long-term weight loss but unfortunately such a procedure in very obese patients is not without risk. The following therefore are the criteria, currently considered for surgical intervention:

BMI greater than 40kg/mt
No significant psychiatric illness and/or history of current binge eating.
The presence of one or more medical complications that are likely to improve with significant weight loss.

If a patient fits these criteria and is keen to pursue surgical intervention then the following steps should be taken:

Medical assessment to determine whether there is any pre-existing contraindications for general anaesthetic and/or surgery.
Clinical Psychology assessment (RVI) to ensure that the patient is psychologically suited to the procedure (a psychiatrist may be involved at this point).

If at this stage the patient is suitable for surgery and satisfies the above requirements then the patient may be referred to the Freeman Hospital. The options available include:

Gastric binding

This involves the introduction of a silastic band around the stomach with a link to a subcutaneous depot. The band effectively divides the stomach into 2 smaller chambers and the aperture from the upper chamber can be altered by either introducing or removing water from the subcutaneous depot. In this way the amount of weight can be titrated with time. With this procedure the patient has to eat small amounts of food and in the first instance the food has to be liquified to avoid vomiting. This procedure has effectively replaced vertical gastroplasty but both work in the same way.

Bilio-pancreatic Diversion

This procedure involves reducing the length of absorptive small bowel by dividing the bowel and anastomosising the duodenum to the jejunum. The procedure effectively works by producing controlled malabsorption and the patients learn to eat a low fat diet. As there is no blind loop bacterial over growth is not a problem and the side effects that were seen with earlier small bowel procedures have not been reported with this new approach.

Which ever procedure that is adopted the patients require long-term follow up to avoid long-term malnutrition.

Gastric balloon insertion is very occasionally used in massively obese patients to induce weight loss prior to a definitive surgical procedure. Because of the high risk of complications most patients have to be hospitalised for monitoring.

Pharmacological Interventions. Who should be treated?

Drug treatment may be considered for those patients with a BMI >3Okg/M (or a BMI >25 with additional risk factors(2'7)) who have failed to lose weight, or whose weight is no longer decreasing, after at least 3 months of structured dietary management.

Weight loss should be gradual to ensure maximum benefit. The risk of crash diets to get drug treatment should not be underestimated. The patients should be informed that rebound weight gain may occur when therapy is stopped. This cyclical picture can lead to long-term problems with weight management.

Patients should be encouraged to set reasonable short-term goals for weight loss (e.g. loss of 0.5 to 1 kg per week).(4) The main goal for treatment is a 10% weight loss.

It is important that anti-obesity medication is used cautiously and only as an adjunct to diet and lifestyle management.t2~ The appropriate role of medication in the management of obesity has yet to be clarified.

Not all patients respond to drug therapy, therefore treatment should be prescribed for no longer than 12 weeks initially. It should be stopped in those who have not achieved a S?/c weight reduction. If weight loss is achieved continued prescribing must be in conjunction with weight monitoring. The duration of treatment must never exceed the time period recommended in the product license (4)

Drug therapy in the UK is not recommended as part of routine maintenance beyond 12 months. Benefits have been demonstrated in trials of up to 6 months of treatment. However weight loss tends to plateau by about 6 months and there is a tendency to partial weight regain despite continued drug therapy. (4)

Before commencing drug treatment for obesity the following needs to be assessed:

Initiation of drug treatment will depend on the clinicians judgement weighing the risks of treatment against the risks to individual from continuing obesity
Drug treatment may be particularly appropriate for patients with co-morbid risk factors or complications from their obesity
A drug should not be considered ineffective because weight loss has stopped, provided the lowered weight is maintained.

The choice of agent will largely depend on the experience of the prescriber. Failure to achieve satisfactory weight loss with one agent may indicate a trial of an alternative compound at a later stage. There is no evidence at present as to whether patients who are non-responders to one drug will also be non-responders to another. Combination therapy of two compounds cannot be recommended until efficacy and safety trial data have been published.(3)

Bulk forming agents

Types of drug treatment for obesity(3) Bulk forming agents

There is no published evidence to suggest that bulk forming agents (e.g. methylcellulose) have any beneficial long-term effect for weight reduction(3).

Methylcellulose

A bulk forming drug is claimed by the manufacture to reduce food intake by producing feelings of satiety, but there is no evidence from RCTs that it is effective in producing weight loss(4) or has long term beneficial effects on weight reduction(s).

Pancreatic lipase inhibitors

Orlistat

Orlistat does not possess central activity. It acts by blocking the absorption of fat by inhibiting gastric and pancreatic lipase enzymes.(2)

Orlistat taken with an appropriate diet promotes modest weight loss and reduces weight regain in obese patients over a 2 year period. Positive changes of a similar magnitude are seen in lipids, fasting glucose levels and blood pressure.(2)

Less than 5% of an oral dose of orlistat reaches the systemic circulation and the main adverse effects are gastrointestinal (abdominal pain, oily or liquid stools, faecal incontinence). These effects become attenuated with time, which may be due to patients avoiding high fat meals which exacerbate them. There is evidence of reduced absorption of fat soluble vitamins.(2)

In order to select those patients likely to respond as well as not to unduly expose patients to orlistat, patients who are unable to lose more than 2.5kg over a period of 4 consecutive weeks despite an appropriate hypocaloric diet, should not be treated. After 12 weeks of treatment, if the patient has not lost at least 5% of body weight at the start of therapy, then orlistat should be discontinued. Maximum duration of treatment should be no longer than 12 months.(2)

It is of great importance that follow-up treatment is of sufficient length to establish long-term patterns of weight loss. The pattern of long term weight loss and long term weight regain justifies the use of a minimum 12 month observation period. Guidance produced by the Royal College of Physicians states that drug use should be limited to one year and anyone failing to lose 10% of their weight by 3 months should discontinue their prescription.(7)

Centrally acting anti-obesity drugs

Drugs acting on serotonergic pathways

The two drugs from this category fenfluramine and dexfcnfluramine, have recently been withdrawn because of concerns of their safety. As a result, they will not be considered further.(2'3'8)

Drugs acting on catecholamine pathways (3)

Phentermine is a drug with minor sympathomimetic and stimulant properties. Given as an oral sustained release resin complex, it is well absorbed from a small intestine producing peak plasma concentrations within 8 hours of administration and therapeutic concentrations persisting for at least 20 hours. Although phentermine has mild stimulant properties, its abuse potential appears to be low. The dose is 15-30mg before breakfast. The use of phentermine is not currently recommended beyond 12 weeks. The use of phentermine is limited by the intolerance of its stimulatory activity (insomnia, headache, and irritability) and other adverse effects including hypertension, tachycardia and the risk of dependence.(2)

Drugs acting on noradrenergic and serotonergie pathways

Sibutramine is a centrally acting noradrenergie and serotonin re-uptake inhibitor.

Sibutramine is thought to act principally by enhancing satiety. It may in addition have a small effect in prevention of decline of resting energy expenditure which is associated with weight loss.

Dose related weight loss has been observed in clinical studies. Most loss occurs in the first 6 months and one study has shown that this is maintained during 1 years treatment. Preliminary data suggests that weight loss is associated with decreases in fasting blood glucose, insulin and triglycerides. Approximately 10% of patients fail to respond to sibutramine.(9)

It is of great importance that follow-up treatment is of sufficient length to establish long-term patterns of weight loss. The pattern of short term weight loss and long term weight regain justifies the use of a minimum 12 month observation period. Guidance produced by the Royal College of Physicians states that drug use should be limited to one year and anyone failing to lose 10% of their weight by 3 months should discontinue their prescription. (7)

Sibutramine may offer an increase of therapeutic options in a weight management programme particularly for those with co-morbidity risk factors or complications of obesity where dietary methods have been unsuccessful.

Adverse effects include dry mouth, constipation, insomnia and dizziness. Increases in heart rate have been noted, as have increases in blood pressure in normotensive patients (2)

Assuming sibutramine costs between £l00-£200 for a 3 months course and, after several years is used by 1% of the population then the annual cost would be £300,000 to £600,000 for Northumberland. Whether this cost is off-set by a reduction in direct costs of other health interventions remains to be seen. Results of 24 month efficacy studies are awaited. The risks and benefits remain to be established. (9)

Other Agents

Fluoxetine may also inhibit appetite and was associated with a greater initial weight loss compared to placebo. Diethyipropion and mazindol are other drugs that suppress appetite and have been used in the treatment of obesity.(2)

Over the counter therapies for obesity (3)

Numerous compounds available over the counter or through mail order are prbmoted as weight loss remedies. Samples of these include herbal remedies, fat magnets and slimming patches. Many claim rapid and substantial loss of fat tissue but such claims are not supported by published scientific evidence nor the results from randomised controlled trials. Furthermore the rate of weight loss promoted as a possible consequence of the use of certain compounds is medically undesirable. Many healthcare professionals consider that medicinal claims for these compounds should require them to be evaluated and licensed as a medicine prior to them being made available to the public. (3)

Drugs not appropriate for the treatment of obesity (2,3,11)

Diuretics, human chorionic gonadotrophin (HCG), amphetamine, dexamphentamine and thyroxine are not treatments for obesity and should not be used to achieve weight loss. Under no circumstances should thyroxine be prescribed for obesity in the absence of bio-chemically proven hypothyroidism. Metformin and acarbose may be useful in the management of the obese non-insulin diabetic patient; they have no proven efficacy for obesity alone and are not licensed for such use.

Appropriate prescribing on the basis of available evidence is to prescribe a compound for no longer than 12 weeks in the first instance, and then to assess weight loss. It will be advisable to stop the drug in those patients who have not achieved a 10% weight loss from the start of the episode of care. This is because the published evidence suggests that they will not respond to the drug in the longer term. In contrast if a 10% weight loss is achieved the drug may be continued beyond this initial period as long as weight is constantly monitored. The drug should not be continued if there is a subsequent weight regain.

Drugs which may cause weight gain