What are the key symptoms of bulimia?

Transcription

1 What are the key symptoms of bulimia? Bulimia has a number of key symptoms. These are: A. Episodes of binge-eating: This means that the person has eating episodes where in one go they eat an amount of food that is larger than what most people would eat in a similar period of time and under similar circumstances. In addition the person has a sense of lack of control over eating during the episodes (e.g. a feeling that they cannot stop eating or control what or how much they are eating). B. Unhelpful reversing behaviours in order to prevent weight gain, such as making oneself vomit, using laxatives, diuretics, enemas, or other medicines in larger than the prescribed dose; fasting; or exercising excessively. C. The person s view of themselves and self-esteem is unduly influenced by their body weight, shape and appearance. E. The person is within the normal weight range. Please note: To be eligible for the BYTE project participants do not have to have all these symptoms. For example, some people may not have big binges, but may have a sense of loosing control when eating small amounts of food that they consider as forbidden or harmful. Who gets bulimia? 90% of people with bulimia nervosa are female. About 1-3% of young women in the community suffer from bulimia. The typical age of onset is round age 15 to 16. All social classes are affected. What causes bulimia? There is not one single cause of bulimia. Our contemporary Western obsession with slimness certainly plays an important role in the recent increase of the problem. A long list of risk factors are thought to play a role in the development of bulimia. Many of these are not specific to bulimia, but are shared with other psychological disorders such as depression or anxiety disorders. These include genetic factors (such as genetic tendency to plumpness or having a strong appetite), a family history of psychiatric disorders (such as an eating disorder, depression or alcohol problems) or obesity, pregnancy complications, childhood temperament/personality factors (e.g. such as being very anxious or very perfectionist, having a negative view of one-self), other childhood factors (e.g. being bullied), family factors (e.g. high parental expectations, adverse family circumstances, having family members who are critical of the person s weight and shape) and peer-influences (e.g. having a peer group that is very in to appearance and weight). The two most potent risk factors for bulimia are having a negative view of one-self and strict dieting. Often an upsetting or stressful life event or major difficulty precipitates the onset of dieting. Thus dieting becomes a way of giving oneself a psychological makeover that then backfires and leads to the development of bulimia.

2 What keeps bulimia going? The diagram below can help you understand the kind of vicious circle that people with bulimia often get into and which makes it hard for people to stop their behaviours. A: Biological factors (food restriction/dieting, disruption of satiety mechanisms) Events leading up to the binge Thoughts leading up to the binge Feelings leading up to the binge B: Craving E: Reversing behaviours such as vomiting, laxatives, diuretics or starving C: Food eaten during the binge D: Thoughts and emotions after the binge

3 Binge eating is the body s physiological response to being undernourished. Over the history of humankind there have been many periods where food was scarce and many outbreaks of famine. Thus as a species we are programmed to cope with periods of famine. Most of us have a very strong drive to eat when our weight is falling, such as happens during dieting (see box A). Our body s way of telling us this is through cravings for food (see box B). In bulimia, bingeing often starts when a person has dieted for a while and may be tremendously pleased with her weight loss. Others may be complimentary about her having achieved this. Thus to start bingeing is like her worst nightmare coming true, feeling that she is loosing control over her food intake. Often satiety mechanisms in the brain become disrupted, so the person literally doesn t know when she is full (see box A). In addition to these biological factors binges are often triggered by difficult events, thoughts and feelings. For example, binges often occur when the person is feeling upset or low, anxious, lonely or bored and bingeing may temporarily reduce these difficult feelings (Box B) During a binge people often eat foods that they would not allow themselves at other times, such as high calorie, fatty or sugary foods. People often have difficult thoughts and feelings after a binge. Many feel very ashamed and disgusted with themselves, depressed or even suicidal. Difficult thoughts include: I am useless, hopeless, a total failure. I will be big as a house, I will balloon up. (box C) Because people typically feel so very bad about bingeing, they may start using unhelpful or dangerous reversing behaviours. The most common of these is being sick. This may initially happen because the person has eaten to bursting point and the food just comes up. Or the person may get introduced to it via friends or the media. It may seem to them like a way to Have your cake and eat it. However, soon a vicious circle is set up where the person binges because they know they can be sick after, and having been sick they usually crave for more food. It also trains people to either have a stomach that is overfull or totally empty and has a number of medical complications too (box E). Other people use laxatives, diuretics or herbal preparations (e.g. stimulants) as reversing behaviours. None of these have any effect on reducing weight. However, they do make the person loose water and bloods salts and especially in people who are underweight this can be very dangerous. The body fights against the loss of water and retains excess water with the result that the person feels puffy and bloated, weighs more and may develop oedema, i.e. visible water retention in their legs. This often leads to people redoubling their efforts to take more of these substances another vicious circle.

4 What other problems occur in bulimia? People with bulimia often also have depression or anxiety disorders at some stage in their life. A proportion of people with bulimia have a number of risky and impulsive behaviours, such as drinking too much, taking drugs, shop-lifting, self-harming or suicidal behaviour, or having unprotected sex. In these cases bulimia may be just one of a number of difficult behaviours for the person. What are the medical risks of bulimia? The physical complications of bulimia nervosa mainly result from vomiting, laxative and diuretic misuse, and to a lesser extent they may also be linked to dietary abnormalities. They include: Dental problems: Tooth surface loss results from regular vomiting, but also from taking plenty of acidic foods such as fizzy drinks and from brushing of teeth following vomiting (this rubs the stomach acid into the teeth). Caries may develop as a result of eating large amounts of sugary foods. A dry mouth, due to anxiety, depression, antidepressant treatment or diuretics may increase the rate at which dental decay occurs. Skin problems: Dry skin is often the result of dehydration in bulimia. People can develop calluses on the knuckles of the hand, which are the result of using the hand to make oneself sick. Bones: Bone mineral density is lowered in individuals with bulimia nervosa who have a history of anorexia nervosa. Fluid imbalance and imbalance of blood salts: Dehydration occurs as the result of fluid loss following vomiting, laxative or diuretic abuse. This can lead to low blood pressure and fainting. About 50% of people with bulimia have electrolyte (blood salts) abnormalities on routine screening. Doctors are particularly worried about low potassium levels. When potassium is only slightly low this can make the person feel tired and exhausted. Very low potassium levels are dangerous as they can lead to seriously irregular heartbeat or epileptic fits. Other electrolyte abnormalities also occur. Blood cells: Anaemia (i.e. not having enough or poorly functioning red blood cells) is common, resulting from deficiencies in micro-nutrients such as iron, trace elements and vitamins. Problems of the digestive tract: These are common and include enlarged salivary glands in people who vomit regularly; inflammation of the gullet (oesophagitis) and oesophageal perforation (rare), changes in stomach emptying (so that food sits in the stomach like a lump of concrete), fatty stools and protein-loss from the bowels, constipation, ileus, and rectal prolapse. Kidney problems A number of renal problems can also occur as a result of bulimia, which include kidney failure due to dehydration and low potassium and kidney stones, again due to dehydration. Reproductive function Approximately 60% of people with bulimia have problems with their periods being irregular or absent. Difficulties with conception are common, when the disorder is active. In those who do manage to conceive despite active bulimia, there is a greater risk of miscarriage, severe morning sickness and low birth-weight of the baby. What medical assessment should someone with bulimia have? At assessment a careful history should be taken to reveal the presence and frequency of bulimic behaviours and any additional problems. A physical examination should be conducted. Laboratory investigations at a minimum should include a full blood count and urea and electrolytes. An ECG is recommended in those who vomit or purge very frequently (e.g. several times daily). What are the best available treatments? Cognitive behaviour therapy (CBT) is the best evaluated and most widely used treatment for bulimia nervosa and should be considered as the first line treatment (see also NICE guideline on eating disorders, 2004). The web-based multi-media package used here Overcoming bulimia is

5 based on this approach. What exactly is CBT? CBT for bulimia is designed to help people establish links between their thoughts, feelings or actions and their current eating disorder symptoms and to re-evaluate their perceptions, beliefs or reasoning about the symptoms. CBT involves: (1) monitoring thoughts, feelings or behaviour about the symptom; (2) being helped to use different ways of coping with the symptoms; (3) reducing stress. In this treatment people are actively involved in their own recovery and are expected to do self-help assignments between sessions. Medication: Different antidepressants have been tested in the treatment of bulimia. Virtually all classes of antidepressants have been found to reduce bingeing and /or purging in the short term. However, very little is known about the longer-term effectiveness of antidepressants. The antidepressant fluoxetine (prozac) is widely used as an antibulimic drug. It is most effective if used at a dose of 60 mg/day rather than at the usual antidepressant dose of 20 mg/day. However, even at a dose of 60 mg/day only 20% of patients become symptom-free. Course and Outcome The typical duration of bulimia nervosa is between 3 to 6 years. Without treatment bulimia runs a fluctuating, chronic course. Of those receiving treatment 50% to 70% are symptom-free 5-10 years after presentation. 9-20% continue to meet full criteria of the disorder and 3-4 % develop anorexia nervosa. The remainder develop a range of milder eating disorders including non-purging bulimia nervosa, binge eating disorder, eating disorder not otherwise specified or obesity. The risk of relapse, i.e. symptoms restarting after successful treatment, is substantial. Depending on precisely how this is defined, relapse rates range from 21% to 55% within the first 1 to 2.5 years following treatment. Thereafter, risk of relapse lessens.