OBESITY – TREATMENT (Dietary Regulation and Drugs)
TREATMENT OF OBESITY
Strong motivation of the patient is absolutely essential for successful management. Dietary regulation is the basis of modern therapy. Calorie intake should be reduced below the basal requirements and the patient has to be kept on negative energy balance over prolonged periods of time. The excess fat is catabolized and weight is lost.
The therapeutic diet should contain 500-1000 Cals less than the energy expenditure of the individual. An ideal weight reducing diet should be:
1. Deficient in calories
2. Otherwise nutritionally adequate, and
3. Acceptable socio-culturally.
4. The diet should be suitably timed to avoid long intervals between eating.
Since dietary fats account for the palatability of food and they provide the maximum amount of calories the first step should be to cut fat intake to the maximum. This is the most effective single step to bring down weight rapidly in the initial stages. Young and tall subjects lose weight more efficiently than older and shorter people. On an average, daily intake has to be limited to 800-1000 calories. More drastic cuts on foods are frequently resented and result in non-compliance. For optimal results the diet should be acceptable, sufficient in volume and conforming to the general eating habits of the individual.
Bulk is provided by adding moderate amounts of fresh vegetables (not curried) and low-calorie fruits. Vegetables when made into curries with coconut, oil, dhal and condiments become very rich in calories. Clear instructions on the exact quantity of food and its timing are very essential. Regular follow-up is necessary for proper motivation and assessment. Patients put on the subcalorie diets lose weight steadily after an initial latent period ranging from days to weeks. It is ideal to reduce the weight by 1 kg a week. Vitamin and mineral supplementation is advisable, since the restricted diet may fail to meet these requirements.
Obese persons do not generally comply with diets. The low caloric diet should be maintained indefinitely since the tendency to regain weight persists. Strong motivation of the patient is needed to achieve good results. Initial motivation to reduce weight may be easy, but persistent efforts to maintain the ideal weight are generally slackened and so a major proportion of patients regain their weight and may even overshoot the original levels. Even moderate reduction in weight such as 6-10% of the body weight is accompanied by reduction in metabolic risks and blood pressure.
Exercise Moderate exercise augments the beneficial effect of dieting. Walking slowly up to 4-5 km, day, swimming, or games are ideal, depending upon individual preferences. Prescription of the exercise regime should take into account the cardiovascular status and exercise tolerance of the patient. Preferably it should be supervised by trained staff.
Several drugs are available which reduce appetite. These anorectic drugs have been employed on short-term basis when the patient is not able to resist the desire to eat. Drugs may be needed when the BMI exceeds 30. Sympathomimetic drugs with amphetamine-like action reduce appetite and increase energy expenditure. These are contraindicated in persons with cardiovascular disease. Serotonin reuptake inhibitors are good appetite suppressants. Fenfluramine and fenoxetine can be given on a shortterm basis over weeks to a few months. When given over prolonged periods they may lead to the development of primary pulmonary hypertension. Acquired defects of the mitral and aortic valves may also develop. Dose Fenfluramine 20-120 mg twice a day given orally one hour before meals. Since these drugs cause dependence, they should preferably be withdrawn after 3 months of administration. Side effects include dryness of the mouth, abdominal pain, drowsiness, alopecia, mental depression, confusion and impotence. These drugs are contraindicated in patients with psychiatric illness.
Sibutramine is an appetite suppressant which can be given in doses of 5-15 mg once a day. It produces loss of weight by reducing appetite and increasing energy expenditure. Side effects include dryness of mouth insomnia and constipation. Sibutramine should not be given to patients with ischemic heart disease heart failure, arrhythmia and stroke. Sibutramine leads to a mean weight loss of 4-5 kg.
Orlistat: It is a lipase inhibitor which prevents absorption of dietary fat. The dose is 120 mg t.i.d. Side effects include flatulence, fecal urgency, and malabsorption of fat soluble vitamins. Orlistat leads to a mean weight loss of 3 kg.
Rimonabant is an endocannabinoid receptor antagonist. The dose is 20 mg given orally daily. It reduces body weight on an average of 4-5 kg. It improves the metabolic syndrome as well. Adverse effects include nausea dizziness, diarrhea and depression. When obesity is extreme and rapid weight reduction is desired, more drastic measures are employed. These include total starvation programmes and surgical procedures.
This can be undertaken under strict medical supervision for 2-3 weeks. Only water, salts and vitamins are allowed during this period. Complications include starvation ketosis, ventricular arrhythmias and sudden death. Due to these risks, total starvation should be undertaken only under exceptional circumstances. Wiring of the jaw to prevent ingestion of solid foods has been practised on persons unable to undertake starvation. Rapid weight loss is achieved by total starvation. Follow-up treatment consists of sub-caloric feeding.
Surgical measures done to produce short-circuiting of digestive and absorptive portions of the intestines may be required for severe cases. The procedures include jejuno-ileal bypass and gastric bypass. Gastric plication may be done with a view to reduce the capacity of the stomach. Extirpation of excessive fat and plastic surgical procedures to remove redundant skin folds remaining after achieving weight loss help to correct cosmetic disability and also to augment the effects of dietary treatment. Liposuction is a surgical technique which removes large amounts of fat from localized areas such as the abdomen, gluteal regions, breasts, arms and face. This procedure is gaining popularity, being safe and cosmetically rewarding. The surgical management of obesity, as a part of cosmetic surgery is known as bariatric surgery.
In general, loss of weight up to 5-10 kg is easy but further reduction and maintenance of the optimal weight demand great motivation on the part of the patient and skill on the part of the physician. Once the optimum weight is reached, the patient should slowly increase the diet to prevent further weight loss, and try to adhere to the optimum weight. Even an occasional dietary excess results in rapid weight gain. All the complications of obesity can be arrested and may even regress if normal weight is maintained for long periods. Secondary obesity should be treated by adopting dietary measures and giving due attention to the primary cause.