Obesity Management in Adults

See related articles: Obesity - the scale of the problem (diagnosis, epidemiological data, risk factors, risks of being obese) and management of obesity in children.

The management of obesity has several facets:

• The prevention of obesity
• The correction of obesity
• The population based approach
• The individual approach.

Prevention is better than cure and rather easier. The population based approach is very important but the doctor in his surgery will have to cope with the individual, and so this will be the thrust of this article.

• It is an irrefutable fact that if energy intake exceeds energy expenditure then weight will be gained. If the two are in equilibrium weight will be static and the only way to loose weight is for energy intake to be less than energy expenditure. A small but consistent excess of intake over expenditure will summate to a large gain in weight over the years.
• Intake is not the only variable and it is possible to vary expenditure too.
• There is no quick fix. Loosing weight is a long and arduous task. The World Health Organisation sees obesity as a chronic disease. Management is not simply helping to shed some unwanted weight but a long-term approach to change attitude, habits and values for the rest of that person's life.

• A patient may present directly asking for help.
• Confrontation of the problem may arise opportunistically when the patient presents for something else.
• It may be a related problem for the patient with diabetes, coronary heart disease, osteoarthritis or snoring.

Urine should be tested for glucose unless the patient is already known to be diabetic or there has been a recent negative test. Fasting blood lipids and glucose may also be required. Otherwise, there is little indication for investigation unless directed by history or examination and routine assessment of thyroid function is unlikely to be rewarding.

The majority of obese patients can be managed successfully by the Primary Health Care team with only a very few requiring referral for specialist help.

The following groups are particularly in need of help and advice:

The following should be included in a plan of action:

• Identify the causes that have made the person obese. There are probably several contributory factors.
• Reiterate why the patient wants to lose weight to emphasise potential benefits and incentives and perhaps to ascertain the degree of motivation.
• Examine what can be done to facilitate weight loss (e.g exercise programme).
• Set realistic targets for rate of loss of weight and desired end point. For a person who has a BMI above 35, the aim of a BMI of less than 25 is probably unrealistic.

Consider cognitive and behavioural therapy to assist in behaviour modification - i.e. help the patient to identify the wrong attitudes and actions in their lives, understand why they are wrong and need to be rectified, identify correct responses and to implement them. There may be "comfort eating" or even clinical depression that needs treatment.

Many practices offer weight management clinics but this is not the only source of help. Some people may prefer to attend Weight Watchers or similar groups.

Aim for both dietary modification and the initiation of exercise. Losing weight without exercise is very difficult. This is one reason for early intervention, before exercise is severely limited by morbid obesity, coronary heart disease, severe COPD, severe osteoarthritis or other such diseases that prevent physical exertion.

Cognition

The first problem may be to convince the patient that he is eating too much. Patients may be adamant they "don't eat enough to keep a sparrow alive". Whilst this may conjure up an amusing picture of an extremely wide sparrow with bowed legs trying to get airborne, it is important to explain to the patient that the equation about calories in and calories out has no exception and the presence of so much surplus fat is testament to a substantial excess of calories over the years. It may be helpful to ask the patient to keep a food diary, including all snacks taken during the day.

Dietary History

The food diary will be over perhaps a week and will reflect a typical day's intake. Do not forget snacks, sweets and treats. Do not forget drinks, whether tea or coffee that may contain sugar or alcoholic drinks. There may be obvious targets for modification. Replace sugar by sweeteners or try to do without them. Use skimmed rather than full fat milk. Perhaps alcohol should be reduced rather than banned as it may represent an important quality of life issue. Alcohol is very high in calories and suppresses blood glucose levels and so can enhance appetite.

Diets

There are many different approaches to dieting and it is important to be flexible to find the one that suits the individual. It is very unpleasant being hungry and rather than just cutting back on all food, it may be easier to move to a diet with less fat and more fibre in it. Counting calories requires obsession and may be counterproductive by making the person more fixated on food than ever. Magazines and the Internet advertise easy ways to lose weight but if there were an easy way, we would all use it. Losing weight is hard and takes tenacity. Herbal and "natural" wonders are also to be avoided as are diets promoted by "celebrities".

Beware of the heartsink patient who wants to tell you how "utterly useless" are all the diets he or she has tried. He is trying to deflect responsibility for his failure away from himself, on to the "failed" diet.

There may be occasions where there is benefit in referral to a dietician. However, if more than a tiny fraction of obese people within the catchment area are referred, it would swamp the service. The practice may have diet sheets to hand out. A simple couple of pages of advice is available online from the Norfolk and Norwich University Hospital.²

Times of Meals

Those who advise about diet almost invariably counsel that breakfast is the most important meal of the day and those who do not have breakfast should introduce it. Eating late at night is bad as the food rapidly turns to fat. This may be true but the evidence for these assertions is limited at best.

People who are obese may have done no exercise for many years. It is important to discuss the options to find something appropriate and sustainable. The age and current level of fitness of the individual must be taken into account. It must also be something that the individual will enjoy or he will not persevere. This is very important as the ethos of exercise is not just for the duration of weight loss, that is a very long process, but for life.

Realistic Expectation

Discuss options and expectations. An overambitious programme is doomed to failure. A programme that is so unambitious that it is pathetically inadequate will confer no benefit. The article on physical training discusses a number of issues related to weight loss, including the concept of the "fat burning zone".

Insulin Suppression

Insulin is highly "anti-lipolytic". This means that it strongly opposes the breakdown of fat. Exercise must be of such duration and intensity to facilitate suppression of insulin levels. People with type 2 diabetes or impaired glucose tolerance, have insensitivity to insulin and basal levels are high. However, this insensitivity includes being less sensitive to its anti-lipolytic actions, so that diabetics are still able to exercise, suppress insulin levels and burn fat.

Expert Advice

Expert advice is that patients should be encouraged to take 30 to 40 minutes of sustained exercise at least 5 times per week³ and introduce more exercise into their daily routine. The initial aim should be towards a daily 500 Kcal deficit of energy requirements through change in dietary habits and exercise. ⁴ Encouragement and support should be given to the patient from the Primary Care Team and regular follow up offered. Ideally a 10% weight loss should be achieved to gain significant health benefits,¹ but realistic targets should be tailored to each individual.

The value of exercise is more than just the calories expended in the session. It tends to increase basal metabolic rate and after vigorous exercise, metabolism is stimulated for the next 36 hours. It also helps people to feel good about themselves. When people start to diet, weight often falls away quite fast at first but the rate of loss then tails away, causing dismay. When people start exercise, weight loss may be slow and disheartening at first as muscle is built, and with it bone for a stronger skeleton. Hence, weight being static may represent fat being replaced by muscle. Not only is muscle more aesthetically satisfying than surplus fat, it is much healthier in terms of improving mobility and preventing falls and it has a much higher basal metabolic rate. Reducing body fat content may improve such parameters as lipid profiles. Exercise will also help and a better diet.

See drug management of obesity.
Drug therapy should not be used from the outset. It is an adjunct and not a substitute for either diet or exercise. Sibutramine⁵ and orlistat.⁶ have been reviewed by NICE, who also outline the limited indications for prescription.⁷

There are a number of drugs that aggravate weight gain⁸ and if the patient takes them, it may be advisable to consider an alternative where possible.

• Oral hypoglycaemic agents, especially sulphonylureas and thiazolidinediones ('glitazones') - so use metformin first-line.
• Antidepressants including tricyclics, mirtazapine, monoamine oxidase inhibitors.
• Anticonvulsants, particualrly sodium valproate, gabapentin, vigabatrin.
• Antipsychotics, especially the atypical antipsychotics amisulpride, aripiprazole, clozapine, olanzapine, quetiapine, risperidone, and zotepine.
• Corticosteroids
• Oral contraceptives, hormone replacement therapy
• Beta-blockers
• Pizotifen

Bariatric surgery is considered elsewhere and has also been reviewed by NICE.⁹ It is limited to the severely obese who are refractory to other management.

As with any chronic disease, follow up must be arranged. This implies interest in the patient's progress. A fortnight to a month would be appropriate at first, with intervals getting longer with time but treat it as a chronic disease. The practice may have a nurse run weight control clinic.

The achievement of a target weight is not the end of the process. Obesity is a chronic disease and needs to be managed througout the person's life as relapse is common. "Yo-yo dieting" with weight going up and down is undesirable and unhealthy.

For those who are obese, any loss of weight is beneficial and, within reason, the more the better. However, the outlook is generally poor. Many people who have consulted a doctor about weight achieve little in terms of weight loss or the loss is only temporary. Nevertheless, the stakes are such that every encouragement should be given to those who wish to try.