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 disruption in the eating behavior along with an excessive concern about body weight that put a negative impact on a person's physical and mental health. The etiology is diverse that include biological, developmental, psychological and cultural factors.Most commonly affected people are adolescents and young females. Eating disorders are categorized as anorexia nervosa, bulimia nervosa and atypical disorders that include binge eating disorder, rumination disorder, pica and night eating syndrome.

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

There are multiple biological and psychological risk factors that play a vital role in the onset of eating disorders as well as other psychological disorders. The risk factors common to both include physical and sexual abuse, problematic parenting and negative affectivity. Certain risk factors are specific to eating disorders such as shape and weight related concerns, dietary restraints and family history of eating disturbance. Genes and environment together put a heavy impact in development of eating disorders; for instance, a highly concerned mother about her weight would be surely concerned of her children's weight. In addition, media and peer group selection also display some association with the development of eating disorder.

Anorexia Nervosa

Template:Seemain Anorexia nervosa is an eating disorder in which patients exhibit immense fear of gaining weight and distorted body image, thereby restrict the required energy intake and display purging practices such as self induced vomiting and use of slimming medicines. This results in a significantly lower body weight(BMI ≤ 17.5) with an unrecognizable seriousness of the condition. In addition, they show an overwhelming behavior of rechecking their weight and body multiple times throughout the day and avail the opportunities to remain physically active. Although the etiology remains unclear; however, certain neurobiological, psychological and environmental factors may play the role. 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 disorder can be defined as consumption of large amount of food over a period of two hours associated with lack of control and feelings of guilt. The episodes occur once weekly over a period of 3 months and the individual does not display any compensatory behavior. There are numerous risk factors that may lead to the disorder such as childhood obesity, substance abuse, conduct disorder, family issues, sexual abuse, physical abuse, and familial eating problems. It is more common in females and the mean age is 23 years. Binge eating disorder is associated with certain comorbid psychiatric conditions that include specific phobia, social phobia, post traumatic stress disorder and alcohol dependence.

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.

Diagnostic Criteria

Anorexia nervosa and Bulimia nervosa are diagnosed on the basis of International Classification of diseases(ICD-10 Criteria) and Binge eating disorder is diagnosed on the basis of DSM-IV and DSM-V.

ANOREXIA NERVOSA

• Actual body weight less than 15% expected or BMI less than 17.5
• Intentional weight loss caused by decreased intake of high calorie food and with either one of the following:

 *self induced vomiting
 *self induced purging
 *excessive exercise
 *use of drugs such as diuretics or appetite suppressants

• Distorted body image as a specific psychological disorder
• Amenorrhea in females and loss of libido in males
• puberty is affected if disorder occurs at a very young age. There is cessation of growth and girls do not develop breast.

BULIMIA NERVOSA

• The patient eats large quantity out of control in a short time because of irrevocable obsession and enormous desire for food.
• Regarding the thoughts of fattening, the patient then make efforts to reduce weight by self induced vomiting or using drugs such as laxatives, thyroid medications, appetite suppressants. Diabetics may restrict their insulin doses.
• Strong desire to obtain a much lower body weight because of intense fear of becoming fat.
• There are times when Bulimia follows an episode of anorexia nervosa.

BINGE EATING DISORDER

• Criteria 1: Recurrent episodes of eating large quantity of food in a particular time period without any control over the amount or type of food being consumed.
• Criteria 2: Binge eating episodes are associated with three of the following

*eating rapidly
*eating until uncomfortably full
*eating greater quantity even not hungry
*eating alone due to embarrassment of over eating
*after binge eating, patient feels depressed or guilty

• Criteria 3: marked distress is evident after binge eating.
• Criteria 4: Binge eating occurs at least 1 day a week for 3 months or 2 days a week for 6 months
• Criteria 5: There is no associated compensatory behavior during the episode of binge eating.

*SEVERITY GRADING IN DSM-V:
*Mild is 1 to 3 episodes per week
*Moderate is 4 to 7 episodes per week
*Severe is 8 to 13 episodes per week
*Extreme is 14 or more episodes per week

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

BULIMIA NERVOSA

Ask: 1.Do you ever eat in secret? 2.How satisfied are you with your eating habits?

Ask 1.previous maximum and minimum weight 2.exercise habits 3.use of alcohol and other drugs 4.binging episodes 5.personal history of rape, depression, childhood abuse or sexual assualt 6.family history of depression or alcohol abuse

Physical examination 1.Bulimics generally look healthy 2.erosion of teeth enamel due to vomiting 3.parotid gland hypertrophy 4.hoarse voice due to GERD 5.Russell's sign-hypertrophy of knuckles due to induced vomiting 6.rectal prolapse or bleeding due to chronic constipation

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