Thursday, January 12, 2012

Bulimia nervosa

Author : Dr Sara M. Buckelew, Assistant Clinical Professor and Director, Eating Disorder Program University of California, San Francisco 2008-07-19

Introduction

Bulimia Nervosa (BN) is an eating disorder, which typically affects 2% of adolescent/young adult women in the United States and other western industrialized nations .[1] The word “bulimia” means a condition characterized by perpetual insatiable hunger with bouts of overeating. BN is a mental health disorder characterized by episodes of overeating followed by some compensatory mechanism aimed at weight loss such as underreating, use of laxatives, self-induced vomiting, or compulsive over-exercise. Most people who have this disorder are characterized as bulimics. The disorder is often associated with depression and anxiety about gaining weight. Individuals with BN have an intense preoccupation with food and their weight. They differ from people who suffer from Anorexia Nervosa (AN) as they are not striving to be thin, the driving force in AN. Most individuals with BN have normal weight. In this knol, when we refer to “Bulimia” we are referring to Bulimia Nervosa (BN).

While bulimia typically affects females, increasing numbers of males are being diagnosed. Additionally, while patients tend to be adolescents and young adults, increasingly there are adults presenting with this disorder. The mean age of onset of the disorder is 18 years of age. In the United States, persons suffering from bulimia are from all different races and ethnicities.

Several studies have documented large numbers of late adolescents and young adults with binge eating or purging behaviors – up to 15% of adolescents and 23% of young adults females, and 14% of young adult males. Most of these individuals while engaging in unhealthy behaviors do not meet the diagnosis of BN. This diagnosis is made based on the criteria of the Diagnostic and Statistical Manual (DSM-IV) (see below).



Physical effects

Bulimia Nervosa is a complex mental health disorder with significant physiological effects. Most of the physical effects are due to either binging, with the excessive intake of calories and fluids, excessive exercise, and/or fasting as a mechanism to deal with the intake of large amounts of calories, or purging through self–induced vomiting, or use of diuretics, ipecac, laxatives, or enemas. Often patients may engage in a number of these activities either simultaneously or consecutively.

Patients suffering from bulimia may complain of:
  • Weight fluctuations

  • Fluid retention and swelling of extremities

  • Weakness and fatigue

  • Chest pain and heartburn

  • Headaches

  • Nausea

  • Abdominal bloating

  • Muscle cramps

  • Irregular menses

  • Diarrhea, sometimes bloody from laxative abuse

  • Bruising

Serious physical effects result from cycles of over-eating and purging, which may occur several times a week or may occur more frequently if the individual is seriously impaired.


The effects may include:
  • Skin changes, including calluses on the back of the hand secondary to abrasions from the teeth when the fingers are used to induce vomiting. Clinicians will call this physical sign the Russell’s sign.

  • Swelling of the face and cheeks, including the lower eyelids, due to increased pressure of blood in the face during vomiting.

  • Enlargement of the salivary glands

  • Dental erosions, tooth decay, and gingivitis

  • Major weight fluctuations

Possible complications the noted systems are :
  • Fluids and electrolytes, including:

    • dehydration
    • low potassium levels
    • low sodium levels
    • low phosphorous
    • swelling of the hands and feet


  • The heart, including:

    • arrhythmias
    • enlargement and damage to the muscles of the heart, secondary to the use of ipecac
    • Changes in blood pressure – low blood pressure
    • The lungs/respiratory system, including: 
      • aspiration pneumonia secondary to vomiting 
      • air in the mediastinum secondary to vomiting

  • The gastrointestinal system, including:

    • swelling of the salivary glands
    • acid reflux 
    • swelling of the stomach, due to large amount of food intake, which may lead to perforation 
    • tears in the esophagus from persistent vomiting 
    • slowing in the time it takes for the stomach to empty 
    • damage to the liver 
    • pancreatitis  
    • bloody diarrhea

  • the endocrine system, including:
    • amenorrhea (periods stopping in females)


Psychological effects


Some behavioral symptoms may include:

  •  depressive symptoms

  • substance abuse

  •  lack of impulse control, including cutting, shoplifting, stealing, and other risky behaviors.

  • being overly concerned with food, weight, and body shape

  • eating in secret, hoarding and hiding of food

  • social isolation, particularly around meals, including avoiding meals with family and friends


Bulimia Nervosa: Criteria For Diagnosis

There is no single blood test or study that a clinician can use to diagnose Bulimia Nervosa; rather BN should be suspected any time an older adolescent/young adult has significant fluctuations in their weight. Other medical conditions that need to be ruled out include a range of gastrointestinal illnesses (e.g., gastroesophageal reflux disease, gall bladder disease, ulcers), malignancies including those of the central nervous system, and pregnancy. See Table 1 for differential diagnosis for BN.
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
BN is diagnosed using a number of clinical criteria. The criteria for BN are listed in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV):[2]

1. Recurrent episodes of binge eating. An episode of binge eating is characterized by both of the following:

a. Eating, in a discrete period of time (e.g., within any 2-hour period), an amount of food that is definitely larger than most people would eat during a similar period of time and under similar circumstances.

b. A sense of lack of control over eating during the episode (e.g., a feeling that one cannot stop eating or control what or how much one is eating).

2. Recurrent inappropriate compensatory behavior to prevent weight gain, such as self-induced vomiting; misuse of laxatives, diuretics, enemas, or other medications; fasting; or excessive exercise.

3. The binge eating and inappropriate compensatory behaviors both occur, on average, at least twice a week for 3 months

4. Self-evaluation is unduly influenced by body shape and weight.

5. The disturbance does not occur exclusively during episodes of Anorexia Nervosa.

There are two subtypes of BN that have been identified:

1. Purging type: During the current episode of Bulimia Nervosa, the person has regularly engaged in self-induced vomiting or the misuse of laxatives, diuretics, or enemas.

2. Nonpurging type: During the current episode of Bulimia Nervosa, the person has used other inappropriate compensatory behaviors, such as fasting or excessive exercise, but has not regularly engaged in self-induced vomiting or the misuse of laxatives, diuretics, or enemas.

Patients who meet the criteria for Anorexia Nervosa, but who also binge and purge, will be diagnosed with Anorexia Nervosa, binge/eating purge subtype not Bulimia Nervosa. (See Anorexia Nervosa knol)

Many patients may fulfill some of the criteria for Bulimia Nervosa but not all of them. They still may struggle with problems with eating and/or problems with body image and weight maintenance. 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. meeting all the criteria for Anorexia Nervosa; however still have normal periods

2. meeting all the criteria for Anorexia Nervosa, however their weight is still within a normal range.

3. meeting all the criteria for Anorexia Nervosa; however maintain a normal body image.

4. meeting all the criteria for Bulimia Nervosa; however 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 chewing and spitting out food, but not swallowing

6. binge-eat cycle but without purging (also known as Binge Eating Disorder)

Despite a difference in the diagnosis, the treatments are 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.



What Causes Bulimia Nervosa

The exact cause of Bulimia Nervosa is unknown, but there are believed to be several factors that may lead to its development. These include biological and genetic factors, psychological factors, and socio-cultural influences.[1] Eating disorders, including Bulimia Nervosa 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 bulimia include depression, anxiety, low self-esteem, personality disorders, disturbances in social functioning (e.g., the lack of ability to have meaningful interpersonal relationships resulting in isolation from normal daily events), substance abuse, and suicidal behavior. There appears to be an association between sexual/physical abuse and BN. Those adolescents presenting with BN may often report that they were overweight at the time they started binging and purging. Individuals with BN tend to come from more disorganized and conflictive families.

 


How Do You Treat Bulimia Nervosa

One of the keys to successful treatment of bulimia is early recognition of the problem and early intervention. Adolescents and young adults 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) or using a BMI calculator. [3],[4] Given that most individuals with BN will be of normal weight, history of binging and purging episodes is critical for establishing the diagnosis. Many adolescents and young adults with BN often have had the disorder for a long period of time before it is discovered, because it is relatively easy to hide. BN rarely presents prior to the age of 14 years. The warning signs (listed below) maybe what a parent notices, such as the patient consuming a notably larger amount of food in a short period of time, or quickly making a trip to the bathroom or shower following eating.


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 is skilled and comfortable in handling eating disorders can monitor weight, vital signs, and other health consequences due to binging and purging. This may be a pediatrician or internist, or may require referral to an adolescent medicine specialist;

  • A dietician or nutritionist who has experience in managing patients with eating disorders can assist with meal planning, and weight stabilization; and

  • A therapist who is knowledgeable about treating eating disorders – specifically BN


Goals of treatment

The goals of treatment include medical, nutritional, and psychological interventions. In treatment of BN, the critical first step is decreasing the frequency of the binging and purging episodes.

Medical monitoring is important initially to make certain the patient’s electrolytes are normalized. Low potassium levels, due to purging, can lead to cardiac arrhythmias and sudden death, therefore it is important to monitor these closely.

Nutritional treatment typically occurs with the guidance of a nutritionist. The goal is to resume healthy eating habits and patterns. Patients should be encouraged not to skip meals, as this may frequently trigger binging later in the day. A nutritionist may develop a meal plan for a patient to ensure they are obtaining optimal calories in addition to resuming well-balanced eating habits. Patients frequently will need to be encouraged to avoid foods that “trigger” binging behaviors. “Trigger” foods vary by individual patients, however may include sugary, carbohydrates, high fat foods or other foods that the patient may consider “unhealthy”. Patients will typically need to increase the variation in the types of food they are eating. Setting realistic weight goals may also be important.

Other important aspects of treatment for bulimia include encouraging regular and moderate physical activity. Regular dental care is important as recurrent self-induced vomiting may cause dental erosions and caries.

Psychological treatment first involves establishing the appropriate aims to improve the patient’s body distortion from over-evaluation of her shape and intense fear of becoming fat, in addition to symptoms of anxiety and or depression that may also exist. Beyond anxiety and depressive symptoms, patients struggling with BN frequently have tremendous shame about their secretive behavior. Other mental health disorders must be considered, including substance abuse, which needs to be treated concurrently with BN.

For adolescents and adults with BN, cognitive-behavioral therapy (CBT) and /or treatment with selective serotonin reuptake inhibitors (SSRIs) have been demonstrated to be effective. CBT targets thoughts, feelings, and behaviors in order to break the binge/purge cycle. In addition, CBT typically includes teaching patients alternate coping skills for anxiety and depressive symptoms. Increasingly, there is a trend to encouraging family therapy in addition to CBT and SSRIs.

Antidepressant medications, particularly selective serotonin reuptake inhibitors have been demonstrated to be effective either alone or in combination with CBT. Individuals who have other mental health disorders may need other psychotropic medications or psychotherapy. Chronic binging and purging may worsen symptoms of anxiety, depression, and obsessive behavior. It is important to reevaluate symptoms throughout the treatment and recovery process.

Treatment may require inpatient hospitalization for medical stabilization. Typically, treatment occurs as an outpatient. 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. Multiple residential programs exist across the United States and typically may benefit those with severe disease who have required previous medical and/or psychological hospitalization and are continuing to struggle.



Long Term Outcomes

Generally, adolescents have better outcomes than adults, which may be due to a shorter length of symptoms among adolescents. Fifty percent of adolescents are thought to fully recover from BN; however, recovery can take many years with a fluctuating course.[5] Studies have shown that the full recovery rate for bulimia is significantly higher than that for Anorexia Nervosa.[6] Given that BN is often associated with other mental health disorders, it is critical for individuals suffering from this disorder to get treatment from a mental health professional.

Mortality associated with Bulimia Nervosa is significantly less than that due to Anorexia Nervosa, but further research and data are necessary.



Warning Signs of Bulimia Nervosa


  • someone who has a history of anorexia
  • someone who is consistently losing or gaining weight in a relatively short period of time.
  • someone who is not gaining weight in a reasonable and expected manner as they go through puberty
  • someone who is using laxatives and other colonic cleansers
  • someone who is making frequent trips to the bathroom, particularly immediately following eating
  • disappearance of food, or indications that a large amount of food was consumed, including empty food wrappers or containers
  • someone who has dental caries and erosion
  • someone who has made previous suicide attempts
  • someone who is skipping meals
  • someone who is making frequent excuses for not eating-“I’m not hungry, I’m too busy, I don’t eat that…” and then eating alone or in secret
  • someone who is complaining frequently of feeling cold, when others do not
  • someone who socially withdraws from activities, particularly activities around food (like going out for dinner or eating with their family)
  • someone who repeatedly weighs themselves
  • someone who is engaging in prolonged periods of exercise, even when feel tired or weak

Promoting good eating habits and a positive body image

1. Parents should be good role models for their children, with health, eating, and exercise habits

2. Don’t diet-have healthy and nutritious eating habits

3. Don’t make negative comments about your own body or anyone else’s

4. Recognize that there are a range of body shapes and sizes

5. Don’t judge a person based on their weight or size, it does not reflect the type of person they are

6. Encourage family meals

7. Encourage regular healthy exercise



Bulimia and the Internet

The majority of Web sites provide a medical view of bulimia, which defines bulimia 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 sites may provide information and support to current sufferers and their friends and family.

Additionally, there is another group of Web sites that argue that eating disorders, including both Anorexia Nervosa and Bulimia Nervosa, are not illnesses but rather a “lifestyle choice.” These pro-anorexia or pro-ana or pro-mia Web sites may contain dangerous and unhealthy information including weight-loss tips and support of the perpetuation of eating disorders. The impact of these sites is unclear, however they may foster the development of an eating disorder in a vulnerable adolescent or young adult.



Similarities and Differences: AN vs BN


AN and BN are both classified as eating disorders, however there are both similarities and differences between the two. Table 2 compares the disorders and how they differ.

 
Table 2: Anorexia Nervosa vs. Bulimia Nervosa
Categories
Anorexia Nervosa
Bulimia Nervosa
Age of Onset
Early/Middle Adolescence
Peak ~ 16 years old
Late Adolescence/Young Adult
Peak ~18 years old
Gender
Predominately female 90%
Same
Prevalence
< 1%
2-4%
Family History
Often positive for history of ED
Same
Physical Health
Underweight, <85 % expected weight

Generally normal weight, may be high or low
Abnormal signs are generally secondary to starvation
Abnormal signs are generally due to purging/binging behaviors
Psychological Symptoms
Preoccupation with weight perfectionist, obsessive
Concern about general size/shape impulsive, self destructive behaviors
May have an associated depression
Often depressed
Low self esteem
Same
Active denial
Usually aware of problem
Families avoid conflict
Families often have active conflict
Pride associated with thinness
Feel shame about their illness
Binge eating may be present
Binge eating must be present
Purging may be present
Same
Treatment
Increase caloric intake to restore normal BMI
Stabilization of weight with emphasis on decreasing purging/binging
Family therapy
Cognitive Behavioral Therapy and/or SSRI’s


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 bulimia 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 bulimia, which makes it different from other disorders, is that it often goes unrecognized because individuals generally are of normal weight and they feel tremendous shame about acknowledging their health problem. If you believe someone you know may have an eating disorder, listen to them and be supportive and encourage them to seek medical treatment.




Websites








Additional resources




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



Le Grange D, Lock J., Treating Bulimia in Adolescents. Guilford Press, 2007.



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.





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

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

[3] Center for Disease Control and Prevention  About BMI for Children and Teens available online.

[4] Center for Disease Control and Prevention.  BMI growth curves available online.

[5]Keel PK, Mitchell JE. Outcome in Bulimia Nervosa American  Journal of  Psychiatry. 1997; 154:313-321. (Pub Med)
[6] Herzog DB, Dorer DJ, Keel PK et al, Recovery and relapse in anorexia and bulimia nervosa: a 7.5 year follow-up study. Journal of American Academy of Child and Adolescent Psychiatry 1999;38: 829-837 (Pub Med)