Eating disorder

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Editor(s)-in-Chief: C. Michael Gibson, M.S.,M.D. [1] Phone:617-632-7753; Mark J. Warren, M.D., M.P.H.,Founder and Medical Director, Cleveland Center for Eating Disorder, Assistant Clinical Professor of Psychiatry, Case Western Reserve University School of Medicine, Cleveland, OH

Overview

An eating disorder is a compulsion to eat, or avoid eating, that negatively affects both one's physical and mental health. Eating disorders are all encompassing. They affect every part of the person's life. According to the authors of Surviving an Eating Disorder, "feelings about work, school, relationships, day-to-day activities and one's experience of emotional well being are determined by what has or has not been eaten or by a number on a scale." Anorexia nervosa and bulimia nervosa are the most common eating disorders generally recognized by medical classification schemes, with a significant diagnostic overlap between the two. Together, they affect an estimated 5-7% of females in the United States during their lifetimes. There is a third type of eating disorder currently being investigated and defined - Binge Eating Disorder. This is a chronic condition that occurs when an individual consumes huge amounts of food during a brief period of time and feels totally out of control and unable to stop their eating. It can lead to serious health conditions such as morbid obesity, diabetes, hypertension, and cardiovascular disease.

Types

• Anorexia nervosa
• Starvation diet
• Binge eating disorder
• Bulimia nervosa
• Diabulimia
• Eating disorder not otherwise specified
• Orthorexia
• Hyperphagia
• Rumination
• Pica
• Night eating syndrome

Risk Factors

Many people believe that eating disorders occur only among young white females, but this is not the case. While eating disorders do mainly affect women between the ages of 12 and 35, other groups are also at risk of developing eating disorders. Eating disorders affect all ethnic and racial groups and while the specific nature of the problem and the risk factors may vary, no population is exempt. Younger and younger children seem to be at risk of developing eating disorders. While most children who develop eating disorders are between 11 and 13, studies have shown that 80% of 3rd through 6th graders are dissatisfied with their bodies or their weight and by age 9 somewhere between 30 and 40% of girls have already been on a diet. Between ages 10 and 16, the statistic jumps to 80%. Many eating disorder experts attribute this behavior to the effects of cultural expectations. Stress is also considered to be a factor in the development of eating disorders. According to Abigail Natenshon, a psychotherapist specializing in eating disorders, children as young as 5 show signs of stress related eating disorders. This includes compulsively exercising and running to burn off calories. Natanshon notes that as children reach puberty younger and younger, they are less equipped to understand the changes in their bodies. They understand the message of the media to be "thin" and try to fit in without comprehending the effects on their bodies. While eating disorders affect younger and younger children, not only girls but also boys suffer from eating disorders. Boys who participate in sports where weight is an issue and often boys who experience issues regarding sexual identity are at risk of developing eating disorders.

Anorexia Nervosa

Template:Seemain Anorexia nervosa is deliberate and sustained weight loss driven by a fear of becoming overweight and a distorted body image. It is not to be confused with anorexia, which is its symptomatic general loss of appetite or disinterest in food. DSM-IV characterizes anorexia nervosa as:

• An abnormally low body weight (the suggested guideline ≤ 85% of normal for age and height, or BMI ≤ 17.5).
• For postmenarcheal females, amenorrhea (the absence of three consecutive menstrual cycles).
• An intense fear gaining weight or becoming fat and a preoccupation with body weight and shape.

Most anorexics become so as adolescents, with 76% reporting onset of the disorder between the ages of 11 and 20. The mortality rate for those diagnosed with anorexia nervosa is approximately 6%—the highest of any mental illness—with roughly half of those due to suicide.

Anorexics are commonly perfectionists, driven to succeed; yet they set unattainable standards of performance for themselves. When they fail to meet these standards, they look for a part of their lives they can control; food and weight become that “control” for them. Low self-esteem and constant self-criticism cause anorexics to constantly fear losing control, and even consuming a small amount of food could be considered a loss of control.

Bulimia Nervosa

Template:Seemain Bulimia nervosa is a cyclical and recurring pattern of binge eating (uncontrolled bursts of overeating) followed by guilt, self-recrimination and overcompensatory behaviour such as crash dieting, overexercising and purging to compensate for the excessive caloric intake.

Bulimics often have "binge food," which is the food they typically consume during binges. Some describe their binge episodes as a physical high they feel, numbing out, going into auto-pilot, losing all control, immediate comfort, etc. The reasoning or triggers behind a binge may serve different purposes for different people. This binge episode leads the individual to feel guilt, shame, embarrassment, and complete failure. Bulimics try to regain control of themselves and the situation by purging the food–making up for their mistake. This leads to feeling famished and empty again, and therefore, another uncontrollable binge, followed by feeling powerless, and the vicious binge/purge cycle continues. Bulimics have extreme eating and exercising habits, instead of demonstrating moderation. This compulsive behavior is often echoed in similar destructive behavior such as sexual promiscuity, pathological lying, and shoplifting. Some bulimics not only struggle with the eating disorder, but these other harmful behaviors as well.

Binge Eating

Binge eating is one of the most common eating disorders. It involves the consumption of very large amounts of food in a short period of time. About 3% of all adults in the United States struggle with Binge eating. People at any age can develop this particular order, but it is seen in most adults ranging from age 46 to around age 55. Clinical studies have continued to find that obese binge eaters have much higher levels of depression than other obese individuals that do not have a binge eating disorder (Susan Himes, 2005). The individual has feeling of disgust and guilt which in turn leads to depression. People that struggle with Binge eating are likely to have alcohol problems, and impulsive behavior, such as not thinking before acting out. They do not feel like they can control themselves, are typically not close with their community, and have difficulty discussing their problems and feelings. They also report to have more health problem, a hard time sleeping at night, joint pain, muscle pains, menstrual problems and headaches. These people often think suicidal thoughts, struggle digesting their food, and are stressed. People that have a Binge eating disorder are usually very ashamed and become very good at hiding the fact that they have it. They become so good at hiding their disorder that most people around them, including close friends and family members, do not even know about their struggle ("Binge Eating Disorder", 2008)

Orthorexia Nervosa

Orthorexia Nervosa is a recently discovered disease because it was thought to be Anorexia earlier on. This type of disorder is an obsession with eating only healthy types of foods. This disease usually occurs when people are so driven to become thin that they start to become obsessed with everything that they are consuming. Someone who struggles with Orthorexia Nervosa will do things like planning out their meals for the next day. This means that they will have a strict planned schedule of breakfast, lunch and dinner. This person will try to be constantly limiting the amount of food that he/she is eating in order to maintain a certain weight. People who have Othorexia Nervosa are often critical of what others eat, and usually isolate themselves from social surroundings ("Eating Disorders", 2001).

Compulsive Exercising

Compulsive excercising is another type of eating disorder. One that struggles with this disorder takes part of vigorous physical activity to the point that it is not healthy and unsafe. It is often referred to as obligatory exercise or anorexia athletic. The individual usually starts to feel compelled to exercise and has problems with anxiety and guilt if he/she does not get their exercises in. Someone that has compulsive exercising disorder will still force themselves to work out even if he/she is sick or injured. They often calculate how much they have eaten and exercise on the amount of calories they have eaten and usually have low energy because of all the calories they have burned (Tiemeyer, 2008). People who struggle with this disorder usually do it to have more control in their life. Praise is often given to the individual about how in shape he/she may look which gives that person more of a drive to continue to work out. Females most commonly have compulsive exercising disorder and measure their self worth through their performance. They often take out their emotions like anger, depression, or frustration when exercising by pushing their bodies to the limit (Mary L. Gavin, 2007).

Causes

Environmental

The media may be a significant influence on eating disorders through its impact on values, norms, and image standards accepted by modern society. Both society’s exposure to media and eating disorders have grown immensely over the past decade. Researchers and clinicians are concerned about the relationship between these two phenomena and finding ways to reduce the negative influence thin-ideal media has on women’s body perception and susceptibility to eating disorders. The dieting industry makes billions of dollars each year by consumers continually buying products in an effort to be the ideal weight. Hollywood displays an unrealistic standard of beauty that makes the public feel incredibly inadequate and dissatisfied and forces people to strive for an unattainable appearance. This takes an enormous toll on one's self-esteem and can easily lead to dieting behaviors, disordered eating, body shame, and ultimately an eating disorder. In addition, bullying is also a major risk factor for the development of AN in girls. Environmental factors influence the biology of the body indirectly causing eating disorders.

Biological Factors from genetic perspective

Recent hypothesis illustrate the influence of GI microbiota in eating disorders. Certain array of products such as short chain fatty acids modulate the metabolic, immune and central nervous system, thereby altering the hunger and satiety. These products stimulate enteroendocrine cells and modify the secretion of hormones. In addition, Lipopolysacchride produced by the bacteria increase the permeability of blood brain barrier to cytokines which modulate appetite regulation.. Moreover, the antibodies produced against the microbial peptides act against regulating hormones including α-MSH. Furthermore, caseinolytic protease B produced by the enterobacteria mimic α-MSH.

Biological

Patients with severe obsessive compulsive disorder, depression or bulimia patients were all found to have abnormally low serotonin levels. Neurotransmitters such as serotonin, dopamine and norepinephrine are secreted by the intestines and central nervous system during digestion.

Researchers have also found low cholecystokinin levels in bulimics. Cholecystokinin is a hormone that causes one to feel full and decreases eating. Low levels of this hormone are likely to cause a lack of satiative feedback when eating, which can lead to overeating. Another explanation researchers found for overeating is abnormalities in the neuromodulator peptides, neuropeptide Y and peptide YY. Both of these peptides increase eating and work with another peptide called leptin. Leptin is released by fat cells and is known to decrease eating. Research found the majority of people who overate produced normal amounts of leptin but they might have complications with the blood-brain barrier preventing an optimal amount to reach the brain.

Cortisol is a hormone released by the adrenal cortex which promotes blood sugar and increases metabolism. High levels of cortisol were found in people with eating disorders. This imbalance may be caused by a problem in or around the hypothalamus. A study in London at Maudsley Hospital found that anorexics were found to have a large variation of serotonin receptors and a high level of serotonin.

Many of these chemicals and hormones are associated with the hypothalamus in the brain. Damage to the hypothalamus can result in abnormalities in temperature regulation, eating, drinking, sexual behavior, fighting, and activity level. Uher & Treasure (2005) performed a study researching brain lesions effects on eating disorders. They evaluated 54 formally published cases of eating disorders and brain damage. They found many correlations between eating disorders and damage to the hypothalamus. People with brain lesions in the hypothalamus had abnormal eating behaviors; unprovoked and self induced vomiting, over concern with becoming fat, cheating with eating, frequent sleepiness, depression, obsessive compulsive behavior and diabetes insipidus.

While scientists have determined that there are possible biochemical or biological causes leading to eating disorders because certain chemicals which control hunger, appetite or digestions are out of balance, experts such as Dr. Edward J. Cumella, executive director of the Remuda Treatment Programs, states that there are three components to eating disorders: 1. The genetic component; 2. The unique environmental factors, such as personal experiences; and 3) The shared environmental factors, such as culture. According to Dr. Cumella, "Some people are born with a predisposition to having an eating disorder and there are genetic markers that can push a person in the direction of anorexia or bulimia...but it does not guarantee that a person will automatically suffer from an eating disorder. The environment - a person's life experience - still has to pull the trigger."

Developmental Etiology

Research from a family systems perspective indicates that eating disorders stem from both the adolescent's difficulty in separating from over-controlling parents, and disturbed patterns of communication. When parents are critical and unaffectionate, their children are more prone to becoming self-destructive and self-critical, and have difficulty developing the skills to engage in self-care giving behaviors. Such developmental failures in early relationships with others, particularly maternal empathy, impairs the development of an internal sense of self and leads to an over-dependence on the environment. When coping strategies have not been developed in the family system, food and drugs serve as a substitute.

Trauma

Eating disorders should also be understood in the context of experienced trauma, with many eating problems beginning as survival strategies rather than vanity or obsession with appearance. According to sociologist Becky Thompson, eating disorders stemming from women of varying socio-economic status, sexual orientation and race, and finds that eating disorders and a disconnected relationship with one's body is commonly a response to environmental stresses, including sexual, physical, and emotional abuse, racism, and poverty. This reality is further detrimental for women of color and other minority women, since they are forced to live in a culture that embraces a narrowly defined conception of beauty: "people furthest from the dominant ideal of beauty, specifically women of color, may suffer the psychological effects of low self-esteem, poor body image, and eating disorders."

Gender Differences

"Frequent dieting and trying to look like persons in the media were independent predictors of binge eating in females of all ages. In males, negative comments about weight by fathers was predictive of starting to binge at least weekly."

Exercise addiction is common in men and women, especially in those who suffer from eating disorders and obsessive-compulsive disorder. It is the result of a fear of becoming fat, a rude dislike of the piknoid body type and allowing their need to stay fit to overtake their lives. Exercise addicts are risking their health in order to get a "runner's high." They are in search of the ideal body type and place the importance of exercise above the needs of their children, parents, friends and health.

Diagnosis

Clinically, eating disorders are evaluated using instruments such as the Questionnaire of Eating and Weight Patterns (QEWP), which has specialized versions for adolescents and parents (QEWP-A, and QEWP-P). In addition to evaluating eating patterns, these tests also measure depression.

ANOREXIA NERVOSA

Ask: 1.Do you think you are thin or too thin? 2.What did you eat yesterday? 3.Do you ever binge eat? 4. Do you use any medications such as laxatives or diuretics or diet pills?

Evaluate common symptoms 1.abdominal discomfort 2.bloating or constipation 3.cold intolerance 4.menstrual history 5.exercise habits 6.daytime hyperactivity and insomnia

Physical examination 1.look for orthostatic signs i-e bradycardia and hypotension 2.yellowskin and lanugo hair 3.irregular rhythm 4.peripheral edema 5.mitral valve prolapse it occurs due to size disporption between left ventricle and mitral valve but its reversible with weight gain

Laboratory investigations 1.complete blood count 2.Urea, creatinine and electrolytes 3.blood glucose 4.serum albumin 5.TSH,FSH,LH and prolactin 6.Bone Densitometry 7.Electrocardiogram

References

• Natenshon, Abigail, ed. (1999), When Your Child Has an Eating Disorder: A Step-By-Step Workbook for Parents and Other Caregivers, Jossey Bass, ISBN 0-7879-4578-1
• Thompson, K. J., ed. (2003), Body Image, Eating Disorders, and Obesity: An Integrative Guide for Assessment and Treatment, APA Books, ISBN 1-55798-726-2
• Agras, W. Steward (2004), "The consequences and costs of the eating disorders", The psychiatric clinics of North America, 24 (2): 371, doi:10.1016/S0193-953X(05)70232-X
• Crow, S.; Praus, B; Thuras, P (1999), "Mortality from Eating Disorders—A 5- to 10-Year Record Linkage Study", International journal of eating disorders, 26: 97, doi:10.1002/(SICI)1098-108X(199907)26:1<97::AID-EAT13>3.0.CO;2-D
• Crow, S; Nyman, J. (2004), "The Cost-Effectiveness of Anorexia Nervosa Treatment", International journal of eating disorders, 35 (2): 155, doi:10.1002/eat.10258
• Lauer, C. J.; Krieg, J. C. (2004), "Sleep in eating disorders", Sleep Medicine Review, 8 (2): 109, doi:10.1016/S1087-0792(02)00122-3
• Meads, C.; Gold, L.; Burls, A. (2001), "How effective is outpatient care compared to inpatient care for the treatment of Anorexia Nervosa? A systemic review", European eating disorders review, 9 (4): 229, doi:10.1002/erv.406
• = Zeeck, A.; Herzog, T.; Hartman, A. (2004), "Day clinic or inpatient care for severe Bulimia Nervosa", European eating disorders review, 12 (2): 79, doi:10.1002/erv.535
• Zipfel, S (2000), "Long-term prognosis in anorexia nervosa: Lessons from a 21-year follow-up study", Lancet (North American Edition), 355 (9205): 721