Anorexia nervosa is an eating disorder that involves an inability to stay at the minimum body weight considered healthy for the person's age and height.
Persons with this disorder may have an intense fear of weight gain, even when they are underweight. They may use extreme dieting, excessive exercise, or other methods to lose weight.
Eating disorder - anorexia
Causes, incidence, and risk factors
The exact causes of anorexia nervosa are unknown. Many factors probably are involved. Genetics and hormones may play a role. Social attitudes that promote unrealistically thin body types may also contribute.
More and more evidence points away from the idea that conflicts within a family may contribute to this or other eating disorders. Most mental health organizations no longer support this theory.
Risk factors include:
- Being a perfectionist
- Feeling increasing concern about, or attention to, weight and shape
- Having eating and digestive problems during early childhood
- Having a mother or father with anorexia or addictions
- Having parents who are concerned about weight and weight loss
- Having a negative self-image and a high level of negative feelings in general
- Undergoing a stressful life change, such as a new job or move, or events such as rape or abuse
Anorexia usually begins in adolescence or young adulthood. It is more common in females, but may also be seen in males. The disorder is seen mainly in Caucasian women who are high academic achievers and who have a goal-oriented family or personality.
To be diagnosed with anorexia, a person must:
- Have an intense fear of gaining weight or becoming fat, even when they are underweight
- Refuse to keep weight at what is considered normal or acceptable for her age and height (15% or more below the expected weight)
- Have a body image that is very distorted, be very focused on body weight or shape, and refuse to admit or acknowledge the seriousness of weight loss
- Have not had their period for three or more cycles (in women)
People with anorexia may severely limit the amount of food they eat, or eat and then make themselves throw up. Other behaviors include:
- Cutting food into small pieces or moving them around the plate rather than eating
- Exercising all the time, even when the weather is bad, they are hurt, or their schedule is busy
- Going to the bathroom right after meals
- Refusing to eat around others
- Using pills to make themselves urinate (water pills or diuretics), have a bowel movement (enemas and laxatives) or to decrease their appetite (diet pills)
Other symptoms of anorexia may include:
Signs and tests
Other causes of weight loss or muscle wasting must be ruled out with medical testing. Examples of other conditions that can cause these symptoms include:
Tests should be done to help determine the cause of weight loss, or what damage the weight loss has caused. Many of these tests will be repeated over time to monitor the patient. These tests may include:
The biggest challenge in treating anorexia nervosa is having the person recognize that they have an illness. Most persons with anorexia nervosa deny that they have an eating disorder. Individuals often enter treatment only once their condition is fairly advanced.
The goals of treatment are to first restore normal body weight and eating habits. A weight gain of 1 - 3 pounds per week is considered a safe goal.
A number of different programs have been designed to treat anorexia. Sometimes weight gain is achieved using schedules for eating, decreased physical activity, and increased social activity, either on an inpatient or outpatient basis. Many patients start with a short hospital stay and continue to follow-up with a day treatment program.
Care providers who are usually involved in these programs include nurse practitioners, physicians, a nutritionist or dietitian, and mental health care providers.
Treatment is often very challenging, and it requires hard work by patients and their families. Many therapies are likely to be tried until the patient succeeds in overcoming this disorder.
Patients may drop out of programs if they have unrealistic expectations of being "cured" with therapy alone.
Although a short hospital stay is a common way to start treatment, a longer hospital stay may be needed if:
- The person has lost a lot of weight, such as being below 70% of their ideal body weight for their age and height. Severe and life-threatening malnutrition may require feedings through a vein or stomach tube.
- Weight loss continues despite treatment
- Medical complications, such as heart problems, confusion, or low potassium levels develop
- The person has severe depression or thinks about committing suicide
Different kinds of talk therapy are used to treat people with anorexia:
- Individual cognitive behavioral therapy, group therapy, and family therapy have all been successful.
- The goal of therapy is to change a patient's thoughts or behavior to encourage them to eat in a more healthy way. This kind of therapy is more useful for treating yougner patients who have not had anorexia for a long time.
- If the patient is young, therapy may involve the whole family. Newer approaches look at the family as a part of the solution, rather than as the cause of the eating disorder.
- Support groups may also be a part of treatment. In support groups, patients and families meet and share what they've been through.
Medications such as antidepressants, antipsychotics, and mood stabilizers may help some anorexic patients when given as part of a complete treatment program. Examples include: olanzapine (Zyprexa, Zydis), selective serotonin reuptake inhibitors (SSRIs), and antidepressants. These medicines can help treat depression or anxiety.
Although these drugs may help, no medication has been proven to decrease the desire to lose weight.
Anorexia nervosa is a serious and potentially deadly medical condition. By some estimates, it leads to death in 10% of cases. Experienced treatment programs have a good success rate in restoring normal weight, but it is common for the disease to return.
Women who develop this eating disorder at an early age have a better chance of complete recovery. However, most people with anorexia will continue to prefer a lower body weight and be preoccupied with food and calories to some extent. Weight management may be difficult, and long-term treatment may be necessary to help maintain a healthy weight.
Complications can be severe. A hospital stay may be needed.
Complications may include:
- Bloating or swelling
- Bone weakening
- Electrolyte imbalance (such as low potassium)
- Dangerous heart rhythms
- Decrease in white blood cells which leads to increased risk of infection
- Severe dehydration
- Severe malnutrition
- Seizures due to fluid loss from excessive diarrhea or vomiting
- Thyroid gland problems, which can lead to cold intolerance and constipation
- Tooth erosion and decay
Calling your health care provider
Talk to your doctor if a loved one is:
- Excessively preoccupied with weight
- Restricting his or her food intake
- Severely underweight
Getting early medical help can reduce the severity of an eating disorder.
In some cases, prevention may not be possible. Encouraging healthy, realistic attitudes toward weight and diet may be helpful. Sometimes, talk therapy can help.
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Reviewed By: David B. Merrill, MD, Assistant Clinical Professor of Psychiatry, Department of Psychiatry, Columbia University Medical Center, New York, NY. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.