Basics
Description
Anorexia Nervosa (AN)
- Restriction of intake, leading to markedly low body weight for age, height, and/or developmental trajectory
- Intense fear of gaining weight or becoming fat, or behavior that prevents weight gain
- Severe body image disturbance, undue influence of body weight and shape on self-evaluation, or denial of seriousness of low body weight
- Lifetime prevalence: 0.5% of females in US
- Typical age of onset for AN is bimodal at 13-14 yr and 17-18 yr
Bulimia Nervosa (BN)
- Recurrent episodes of binge eating characterized by:
- Eating an unusually large amount of food in a discrete period of time
- A sense of loss of control over eating during the episode
- Recurrent inappropriate compensatory behaviors used to prevent weight gain:
- Self-induced vomiting
- Misuse of laxatives or enemas
- Diuretics
- Diet pills
- Fasting
- Excessive exercise
- Bingeing and compensation occur on average at least once a week for 3 mo
- Self-evaluation that is excessively influenced by weight or body shape
- Lifetime prevalence: 2% of females in US
- Commonly onset in late adolescence or early adulthood.
Binge Eating Disorder (BED)
- Recurrent episodes of binge eating characterized by:
- Eating a larger than usual amount of food in a discrete period of time
- A sense of loss of control over eating during the episode
- Binge eating episodes associated with 3 or more of the following:
- Eating much more rapidly than normal
- Eating until feeling uncomfortably full
- Eating large amounts of food when not feeling physically hungry
- Eating alone because of embarrassment about how much one is eating
- Feeling disgusted with oneself, depressed, or very guilty after overeating
- Marked distress over binge eating
- Occurs on average at least once a week for 3 mo
- No compensatory behavior
- Lifetime prevalence: 3.5% of females and 2% males in US
- Onset in late adolescence or early adulthood.
Etiology
- Twin studies have supported a strong genetic component.
- Cultural emphasis on thinness as a valued attribute has been implicated
- Temperament or personality attributes of perfectionism, anxiety, and behavioral rigidity have been described
- Family conflict or stress is a frequent element
- Neurochemical (serotonin) and neuroendocrinologic (leptin, HPA axis) abnormalities have been reported
- Dieting is a frequent immediate precipitant
Diagnosis
Signs and Symptoms
History
- Rapid or sustained weight loss
- Typical detailed days eating pattern shows restricting and/or bingeing behavior
- Purging (vomiting, laxatives, diuretics, enemas)
- Excessive exercise
- Dizziness, syncope
- Bloating (gastroparesis), constipation, abdominal pain
- Fatigue, lethargy
- Palpitations
- Cold intolerance
- Amenorrhea, loss of libido
- Family history of eating disorders and obesity
- Comorbid psychiatric disorder (e.g., mood disorder, substance abuse, personality disorder)
Physical Exam
- Weight <85% IBW or BMI <17.5 for AN
- Hypothermia
- Hypotension, orthostasis
- Bradycardia, arrhythmia
- Skin: Dry skin, lanugo (soft downy body hair on chest and arms), carotenoderma
- Breast atrophy
- Parotid swelling, submandibular swelling
- Abnormal dentition
- Abrasions of dorsum of hand
- Skin breakdown, poor wound healing
- Peripheral edema
- Muscle weakness
Essential Workup
- History
- Physical exam
- Lab testing
- Nutritional assessment
- Psychiatric interview:
- Concurrent psychiatric illness
- Suicide risk assessment
- Explore psychosocial context
- Family evaluation when patient lives with his or her family
Diagnosis Tests & Interpretation
Lab
- CBC (anemia, leukopenia, thrombocytopenia)
- Electrolytes, BUN, creatinine, glucose (hyponatremia, hypokalemia, hypoglycemia, dehydration, metabolic alkalosis)
- Calcium, magnesium, phosphorus, albumin (hypocalcemia, hypomagnesemia, hypophosphatemia, hypoalbuminemia)
- LFTs (hepatic dysfunction)
- UA including specific gravity
- Toxic screen
- β-hCG
- Amylase (salivary hyperamylasemia if vomiting, pancreatitis)
- Lipase (more accurate than amylase in predicting pancreatitis)
- Consider checking thyroid-stimulating hormone.
Imaging
Specific tests may be useful in making differential diagnoses, e.g., MRI (rule out brain tumor), abdominal CT (rule out obstruction) á
Diagnostic Procedures/Surgery
- ECG (QTc prolongation, arrhythmia)
- Consider cardiac echo if substantial weight loss (cardiomyopathy from AN or ipecac)
- Bone mineral density (osteoporosis)
Differential Diagnosis
- Medical conditions:
- GI disease (e.g., Crohns Disease, IBD, celiac disease)
- Endocrine disorder (e.g., DM, thyroid disorder, adrenal insufficiency)
- Cancer
- Psychiatric conditions
- Borderline personality disorder
- Mood disorders
- Obsessive-compulsive disorder
- Substance abuse
Treatment
Initial Stabilization/Therapy
- ABCs
- Careful fluid resuscitation for dehydration to avoid precipitating peripheral or pulmonary edema
- Replete phosphate and thiamine since both may drop with refeeding
- Correct hypokalemia, hypomagnesemia, hypocalcemia
- Correct hypoglycemia
- Warming blankets for severe hypothermia
Ed Treatment/Procedures
- Initial workup
- Medical stabilization
- Psychiatric consultation (including assessment of suicide risk and psychiatric comorbidities)
Medication
First Line
- No medication has been demonstrated to be of benefit for AN per se
- Small trials have suggested possible benefit from atypical antipsychotics, particularly olanzapine 2.5-10 mg PO QD
- It may be helpful to treat psychiatric comorbidities
- Only fluoxetine 20-60 mg PO QD has FDA indication for the treatment of BN, though other SSRIs are frequently used. There is also evidence for tricyclic antidepressants as well as topiramate
- There is evidence for imipramine, sertaline, citalopram/escitalopram, and topiramate for BED
Follow-Up
Disposition
Admission Criteria
- Medical risk:
- Extremely low weight (<75% IBW)
- Rapid weight loss
- Serum electrolyte imbalance (K <3, glucose <60)
- Bradycardia <40
- BP <90/60
- Orthostasis (>20 bpm or >20 mm Hg/10 mm Hg)
- Hypothermia <97 ░F
- Arrhythmia or heart failure
- Hepatic or renal dysfunction
- Psychiatric risk:
- Severe depression, psychosis, or other comorbid psychiatric diagnosis
- Suicidality
- Lack of motivation or cooperation with treatment
- Failure of outpatient treatment
- Severe impairment in functioning
- Toxic family environment
Discharge Criteria
- Medically and psychologically safe enough to be managed on an outpatient basis
- Multimodal, multidisciplinary team in place to manage medical, nutritional, and psychological issues
Issues for Referral
- Outpatient treatment requires a team approach composed of a:
- Psychiatrist and/or psychologist
- Nutritionist, preferably one who specializes in eating disorders
- Pediatrician or internist
- Family therapist
- Group therapist
- Dentist
- Prognosis:
- AN and BN:
- 20% chronic course
- 30% improve
- 50% recover
- Mortality rate 5.6% per decade for AN
- Outcomes improved with early diagnosis and treatment
Follow-Up Recommendations
- For outpatient treatment the team must establish modest goals and clear parameters, including expected weight gain for anorexic patients and compliance with follow-up appointments.
- Internist/pediatrician: Monitor vital signs, weight, BMI, electrolytes, and ECG.
- Nutritionist: Monitor diet, calorie intake, and exercise.
- Psychotherapy:
- Cognitive behavioral therapy and interpersonal psychotherapy are the most effective forms of psychotherapy for BN.
- Cognitive behavioral therapy, family therapy, and psychodynamic therapies are all useful for AN.
- Family-based treatment is the preferred therapy for teenagers with AN, and it is promising for teenagers with BN as well.
- Pharmacotherapy:
- Only indicated within the context of psychotherapy, especially with comorbid psychopathology.
- No accepted pharmacologic treatment of AN.
- Case studies suggest that 2nd-generation antipsychotics may be helpful in AN.
- There is no clear evidence for specific treatment of osteoporosis in AN apart from weight restoration and nutritional calcium supplementation.
- Antidepressant medications are shown to significantly reduce bingeing and purging behaviors:
- Fluoxetine is the best studied
Pearls and Pitfalls
- Eating disorders are associated with high medical risk and risk of suicide; prioritize safety assessment
- Rapid restoration of nutrition, volume resuscitation, and/or failure to replete vitamins and electrolytes can result in potentially fatal refeeding syndrome
- Avoid trying to "out-obsess"Ł the obsessional patient
- Coordinate care with PCP and other members of a multidisciplinary team
Additional Reading
- Aigner áM, Treasure áJ, Kaye áW, et al. World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the pharmacological treatment of eating disorders. World J Biol Psychiatry. 2011;12:400-443.
- American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Arlington, VA: American Psychiatric Publishing; 2013.
- American Psychiatric Association (APA). Practice Guidelines for the Treatment of Patients with Eating Disorders. 3rd ed. Washington, DC: 2006, and Guideline Watch (update) August 2012.
- Mascolo áM, Trent áS, Colwell áC, et al. What the emergency department needs to know when caring for your patients with eating disorders. Int J Eat Disord. 2012;45:977-981.
- Mitchell áJE, Crow áS. Medical complications of anorexia nervosa and bulimia nervosa. Curr Opin Psychiatry. 2006;19(4):438-443.
- Rosen áDS, American Academy of Pediatrics Committee on Adolescence. Identification and management of eating disorders in children and adolescents. Pediatrics. 2010;126:1240-1253.
Codes
ICD9
- 307.1 Anorexia nervosa
- 307.50 Eating disorder, unspecified
- 307.51 Bulimia nervosa
- 307.59 Other disorders of eating
ICD10
- F50.00 Anorexia nervosa, unspecified
- F50.2 Bulimia nervosa
- F50.9 Eating disorder, unspecified
- F50.02 Anorexia nervosa, binge eating/purging type
- F50.01 Anorexia nervosa, restricting type
- F50.0 Anorexia nervosa
- F50.8 Other eating disorders
- F50 Eating disorders
SNOMED
- 72366004 Eating disorder (disorder)
- 56882008 Anorexia nervosa (disorder)
- 78004001 Bulimia nervosa (disorder)
- 439960005 binge eating disorder (disorder)
- 16985007 fasting (finding)
- 34923007 self-induced vomiting (disorder)