Anorexia nervosa

Author : Dr Sara M. Buckelew, Assistant Clinical Professor and Director, Eating Disorder Program University of California, San Francisco . 2008-06-10

Anorexia Nervosa (AN) is an eating disorder that typically affects adolescent girls, with an average prevalence of 0.3% in young women. [1] The word “anorexia” means loss of appetite, a symptom in other diseases.  Most people with the diagnosis of Anorexia Nervosa are referred to as having “anorexia,” which is technically not correct. In many ways, people with AN do not lose their appetite, but rather are preoccupied with food. 
 Anorexia Nervosa is characterized by weight loss, a distorted perception of body shape and size, and an intense fear of weight gain.  Frequently, there is also a level of denial about the seriousness of the degree of weight loss.  In this knol, when we refer to “Anorexia” we are referring to Anorexia Nervosa (AN).

William Gull first established the name anorexia nervosa

While anorexia typically affects females, increasing numbers of males are being diagnosed.  Additionally, while patients tend to be adolescents and young adults, increasingly patients of all ages, including children and middle-aged adults are being seen as well.  In the United States, persons suffering from anorexia are from all different races and ethnicities. 

What Causes Anorexia NervosA

The exact cause of Anorexia Nervosa is unknown, but there are believed to be several different factors that may lead to its development.  These include biological and genetic factors, psychological factors, and socio-cultural influences. Eating disorders, including anorexia, run in families, with higher rates among females with identical twins and/or first degree relatives with eating disorders.  Psychological factors that have been shown to be associated with anorexia include perfectionism, anxiety, obsessive, low self-esteem, and low self-confidence.   Society’s increasing emphasis on a thin body ideal may also be a factor, and may further increase low self-esteem and low confidence, resulting in dieting and further preoccupation with thinness.

Over the last few years, the modeling world has responded to this, with at least two countries instituting body mass index (BMI) cut offs for models to be allowed to participate as runway models in corresponding fashion weeks.  The BMI that they established as a cutoff was 18.0 which still constitutes extreme thinness for a young woman, and according to the World Health Organization still would be defined as “underweight.”[2]  The Council for Fashion Designers in America opted not to create BMI cut offs for models in the US. 

Physical effects

Anorexia Nervosa is a complex mental health disorder with significant physiological effects and an associated environmental overlay.  Most of the physical effects and many of the initial alterations in cognitive functioning are due to the degree of malnutrition. 

Patients suffering from anorexia may complain of:

• feeling cold
• fatigue
• dizziness (particularly when standing up)
• constipation
• abdominal bloating
• muscle cramps
• poor concentration 

Serious physical effects of malnutrition may include:

• poor growth, or stunted growth if anorexia develops prior to the completion of the growth (may be more common in males with anorexia as their growth period is longer)
• delayed puberty (can delay the start of puberty or the progression of puberty)
• development of lanugo (fine downy hair over the body particularly the back, stomach, and face)
• hair loss
• brittle hair and nails
• poor blood flow to the hands and feet (acrocyanosis)
• tooth decay
• gingivitis

Complications that may ensue include complications of:

• fluids and electrolytes:
  • dehydration
  • low potassium levels
  • low sodium levels, low glucose
  • low phosphorous
  • low magnesium
  • swelling of the hands and feet
• the heart:
  • low blood pressure
  • arrhythmias particularly a low heart rate (bradycardia)
  • a heart murmur (typically due to  mitral valve prolapse)
  • pericardial effusions
• the bones:
  • osteopenia
  • increased risk of fracture
• the blood system:
  • anemia
  • low white blood cell count 
• the gastrointestinal system:
  • constipation
  • acid reflux
  • tears in the esophagous from  persistent vomiting
  • slowing in the time it takes for the stomach to empty
  • damage to the liver
  • pancreatitis
• the endocrine system:
  • amenorrhea (periods stopping in females)
  • low thyroid hormone levels (due to malnutrition, which corrects with better nutrition;  typically does not require thyroid hormone replacement)
  • high cortisol levels
  • high cholesterol levels
  • low testosterone levels (in males) leading to decreased libido
• the brain
  • effects on cognition
  • changes on radiographic studies
• decreased body temperature

Psychological effects

Some behavioral symptoms may include:

• distortion in body shape and size
• anxiety including obsessive behavior particularly around food
• depressive symptoms
• strict rituals around meal times and involving food
• social isolation particularly around meals, including avoiding meals with family and friends

Anorexia Nervosa Criteria for Diagnosis

There is no single blood test or study that a clinician can use to diagnose Anorexia Nervosa, rather AN should be suspected any time an adolescent develops significant weight loss and food avoidance. Other medical diseases should be ruled out prior to making a diagnosis of AN, such as gastrointestinal illnesses, endocrine problems, and certain types of cancer (see Table 1). 

Table I: Differential Diagnosis for Anorexia Nervosa

Pregnancy

Inflammatory bowel disease including Ulcerative Colitis and Crohn’s Disease

Malabsorptive conditions including Celiac Disease

Diabetes Mellitus

Hyperthyroidism

Collagen vascular disease including systemic lupus erythematous

Central nervous system tumors

Cancer

Chronic infections such as tuberculosis and human immunodeficiency virus (HIV)

Obsessive Compulsive Disorder

Anxiety disorders

Mood disorders such as depression

Psychosis

Substance abuse

AN is diagnosed using a number of clinical criteria. The criteria for AN are listed in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV):[4]

1. Refusal to maintain a minimally normal body weight for age and height
2. Intense fear of weight gain or becoming fat, although underweight
3. Disturbance in the way in which one’s body weight or shape is experienced, undue influence of body weight or shape on self evaluation, or denial of the seriousness of the current low body weight.
4. In post menarcheal females, amenorrhea, that is the absence of at least three consecutive menstrual cycles

There are two subtypes of AN that are described

1. Restricting type: During the current episode of anorexia nervosa, the person has not regularly engaged in binge-eating or purging behavior (i.e., self-induced vomiting or the misuse of laxatives, diuretics, or enemas)

2. Binge eating/Purging subtype: During the current episode of anorexia nervosa, the person has regularly engaged in binge-eating or purging behavior (i.e., self-induced vomiting or the misuse of laxatives, diuretics, or enemas).

Many patients may fulfill some of the criteria for anorexia nervosa, but not all of them.  They still may struggle with problems with eating and/or problems with body image.  They may receive a diagnosis of a “partial eating disorder” or eating disorder not otherwise specified (ed-nos).

The criteria for Eating Disorder NOS according to the DSM IV include:

1. Meet all the criteria for anorexia nervosa, except still have normal periods
2. Meet all the criteria for anorexia nervosa, however their weight is still within a normal range.
3. Meet all the criteria for anorexia nervosa; however maintain a normal body image.
4. Meet all the criteria for bulimia nervosa, except the frequency of binging and purging is less than that specified by the DSM IV necessary to make a diagnosis of bulimia nervosa.
5. Repeatedly chew and spit out but do not swallow their food
6. Binge-eat but do not purge (also known as Binge Eating Disorder)

Despite a difference in the diagnosis, the treatment will be similar, as those who suffer from Anorexia Nervosa, Bulimia Nervosa, and Eating Disorder-NOS all share a pre-occupation with food, as well as with body weight and shape. 

TREATING ANOREXIA NERVOSA

One of the keys to successful treatment of anorexia is early recognition of the problem and early intervention.  Children and adolescents must be weighed and measured at every medical appointment or at a minimum once a year.  A Body Mass Index (BMI) should be calculated and plotted on a growth curve appropriate for the adolescent’s age and gender.  BMI is a tool to screen a person’s nutritional status and is calculated by taking the weight in kilograms and dividing by the height (in meters) squared (BMI = kg/m2). [5],[6] 

 

MultiDisciplinary Treatment team

Successful treatment typically requires a multidisciplinary team knowledgeable in the care of patients with eating disorders.  The team should include:

• A physician who can monitor weight, vital signs and other consequences due to malnutrition;
• A dietician or nutritionist who can assist with meal planning, and weight restoration; and
• A therapist who is knowledgeable about treating eating disorders. 

Goals of treatment

The goals of treatment include immediate weight restoration (returning the patient to a healthy, stable weight). Weight restoration is the critical first step to enable the patient to be capable of benefiting from psychological treatment. Psychological treatment aims to improve the patient’s body distortion and intense fear of becoming fat in addition to symptoms of anxiety and or depression that may also exist.  In the long term, additional goals include resumption of normal menstrual periods, and improved psychological functioning. 

Nutritional treatment typically occurs with the guidance of a dietician  The goal is to resume healthy eating habits and patterns. A dietician may develop a meal plan for a patient to ensure they are obtaining optimal calories in addition to resuming well balanced eating habits.  Patients will typically need to increase the variation in the types of food they are eating.  As patients are improving their nutrition and restoring their weight, they often require zinc supplementation and typically benefit from a multivitamin and calcium and vitamin D supplementation.

For adolescents with AN, family therapy is an effective psychotherapeutic treatment.[7] Typically treatment occurs as an outpatient. Treatment may require inpatient hospitalization for medical stabilization. At times, an intensive outpatient or partial hospitalization may be more beneficial.  For patients who are not responding to outpatient treatment but who are medically stable, residential treatment programs may be necessary. 

The benefits of psychotropic medication, including antidepressants and atypical neuroleptic medications, is unclear, and further research is necessary.^.[8]^{, [9]} Antidepressant medications, particularly selective serotonin reuptake inhibitors (SSRIs)may be beneficial in treating co-existing symptoms of depression or obsessive-compulsive disorder.   Malnutrition itself may worsen symptoms of anxiety, depression, and obsessive behavior.  It is important to reevaluate symptoms throughout the treatment and recovery process. If symptoms persist following weight restoration, medications may be more effective in treating those symptoms.  Depression, anxiety, and substance abuse are the most common other mental health disorders that occur among people with anorexia.

REFEEDING SYNDROME

At times patients may be severely malnourished, requiring acute medical hospitalization. These patients will require being refed in hospital under close surveillance to monitor for “refeeding syndrome.” When the body is severely malnourished, it is in a catabolic state, when the tissues are breaking down into simpler metabolic constituents.  When a patient begins to eat again, there is a surge of insulin as the body switches to an anabolic state, when the body’s chemical processes are constructive, or synthesizing tissues, enzymes and other components.  This surge of insulin can cause shifts in electrolytes, in particular phosphorous, potassium, and magnesium as well as shifts of sodium and water.  The results can lead to cardiac arrhythmias, breakdown of muscle, edema (swelling in the hands and feet), delirium, and even death.

Long Term Outcomes

Generally, adolescents have better outcomes than adults, which may be due to a shorter length of symptoms among adolescents.  Other good prognostic factors include: early identification and entry into treatment, short duration of symptoms, age less than 14 years, no binging and purging (the restricting subtype of anorexia rather than the binge/purge subtype), and no other mental health disorder (such as depression, anxiety, or substance abuse).[10]  Fifty percent of adolescents are thought to have a good outcome; however, recovery can take many years.[11] 

The leading causes of death due to anorexia are by suicide, or secondary to medical complications of malnutrition/starvation.  Mortality rates range from 2% to 8%.

Warning signs of Anorexia

• Someone who appears to becoming thinner and thinner
• Someone who is not gaining weight in a reasonable and expected manner as they are going through puberty
• Complains about being fat when obviously is not
• Skipping meals
• Making frequent excuses for not eating-“I’m not hungry, I’m too busy, I don’t eat that…”
• Someone who continues to diet or lose weight even though he/or she is not overweight
• May complain frequently of feeling cold, when others do not
• Complains about feeling full even after only eating a small amount of food
• Socially withdraws from activities, particularly activities around food (like going out for dinner or eating with their family)
• Repeatedly weighs themselves
• Engages in prolonged periods of exercise even when feeling tired or weak
• Obsessive calorie counting
• Eating rituals such as eating the same food for lunch every day, or needing to cut food into tiny pieces and pushing it around the plate rather than eating it
• Collecting recipes and cooking for others while finding excuses to avoid eating
• Becomes disgusted with foods that were previously favorites

Promoting good eating habits and a positive body image

1. Parents should be good role models for their children, with healthy eating and exercise habits
2. Don’t make negative comments about your own body or anyone else’s
3. Recognize that there are a range of body shapes and sizes
4. Don’t judge a person based on their weight or size, it does not reflect the type of person they are
5. Encourage family meals
6. Encourage regular healthy exercise

Anorexia and the Internet

The majority of Web sites provide a medical view of anorexia, which defines anorexia as a mental health disorder that can be cured.  These Web sites and online communities are run by professionals in addition to those suffering with an eating disorder or a history of an eating disorder.  These resources may provide information and support to current sufferers and their friends and family.

Additionally, there is another group of Web sites, which argue that anorexia is not an illness but rather a “lifestyle choice.”  These pro-anorexia or pro-ana Web sites may contain dangerous and unhealthy information including weight loss-tips and support of the perpetuation of eating disorders.  These Web sites have an unclear impact, however they may foster the development of an eating disorder in a vulnerable adolescent or young adult. [12]

When to seek medical advice

If you are concerned that you may have an eating disorder, see your doctor and express your concerns. Often the grip of anorexia can be so strong, you may resist getting help.  Try to find support from a friend or family member to assist you in finding treatment options. 

 A major challenge in the treatment of anorexia, which makes it different from other disorders, is that frequently those who suffer may not want help or may think it is not necessary.   If you believe someone you know may have an eating disorder, listen to them and be supportive and encourage them to seek medical treatment. 

Web sites

www.somethingfishy.org

www.anad.org

www.edreferral.com

Additional resources

Collins, Laura. Eating with your Anorexic.   McGraw Hill, 2005.

Hornbacher M. Wasted: A memoir of anorexia and bulimia. New York; Harper Collins, 1998.

Katzman DK, Pinhas L., Help for eating disorders; A parent’s guide to symptoms, causes and treatments, Toronto, Canada: Robert Rose Inc, 2005

Lock J, LeGrange D. Help your Teenager Beat an Eating Disorder.  Guilford Press, 2005.

Schaefer, J Life Without Ed: How One Woman Declared Independence from Her Eating Disorder and How You Can Too McGraw Hill, 2003.

 

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[1] Hoek HW, van Hoeken, Review of the prevalence and incidence of eating disorders. International Journal of Eating Disorders 2003; 34:383-396.

[2] World Health Organization Nutrition and food security. Available online at http://www.euro.who.int/nutrition/20030507_1 accessed 1/17/08

[3] Katzman DK Medical complications in adolescents with anorexia nervosa: a review of the literature. International Journal of Eating Disorders 2005; 37 (Suppl) : S52-59

[4] American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 4^th edition. Washington, DC; American Psychiatric Association, 2004.

[5] Center for Disease Control and Prevention  About BMI for Children and Teens available online at http://www.cdc.gov/nccdphp/dnpa/bmi/childrens_BMI/about_childrens_BMI.htm 

[6] BMI growth curves available at http://www.cdc.gov/nchs/about/major/nhanes/growthcharts/clinical_charts.htm

[7] Lock J, Agras WS, Bryson S, et al. A comparison of short and long term family therapy for adolescent anorexia nervosa. Journal of the American Academy of Child and Adolescent Psychiatry 2005; 44(7) 632-

[8] Claudino AM, Hay P, Lima MS, Bacaltchuk J, Schmidt U, Treasure J. Antidepressants for anorexia nervosa. Cochrane Database of Systematic Reviews 2006, Issue 1. Art. No.: CD004365. DOI: 10.1002/14651858.CD004365.pub2

[9] Claudino AM, Hay PJ, Lima MS, Schmidt U, Bacaltchuk J, Treasure JL. Antipsychotic drugs for anorexia nervosa. (Protocol) Cochrane Database of Systematic Reviews 2007, Issue 4. Art. No.: CD006816. DOI: 10.1002/14651858.CD006816.  Available online-for web link http://mrw.interscience.wiley.com/cochrane/clsysrev/articles/CD006816/frame.html

[10] Strober M, Freeman R, Morrell W, et al. The long-term course of severe anorexia nervosa in adolescents: survival analysis of recovery, relapse, and outcome predictors over 10-15 years in a prospective study. International Journal of Eating Disorders 1997; 22: 339-360.

[11] Fisher, M The course and outcome of eating disorders in adults and in adolescents: a review. Adolesc Med 2003; 14: 149-158.

[12] Norris ML, Boydell KM, Pinhas L, Katzman DK, Ana and the Internet: A Review of Pro-Anorexia Websites. International Journal of Eating Disorders. 2006; 39:443-447.