Eating Disorders 

• eating disorders are characterized by a persistent disturbance of eating that impairs psychosocial functioning or health

DSM-5 Classification:

• Changed from “Eating disorders” to “Feeding and Eating Disorders,” including eight categories:
  • Anorexia Nervosa
  • Bulimia Nervosa
  • Binge Eating Disorder
  • Avoidant/Restrictive Food Intake Disorder
  • Pica
  • Rumination Disorder
  • Other Specified Feeding and Eating Disorders
    • Purging Disorder
    • Night Eating Syndrome
    • Atypical Anorexia Nervosa
    • Subthreshold Bulimia Nervosa and Binge Eating Disorder
    • Orthorexia
  • Unspecified Feeding and Eating Disorders

Epidemiology

• anorexia nervosa (AN):
  • 1% of adolescent and young adult females
  • 0.3% males
  • onset in mid-teens (14-18yr)
• bulimia nervosa (BN):
  • 2-4% of adolescent and young adult females
  • 0.5% males
  • onset in late teens or early adulthood
• F:M=10:1
• mortality of AN 5-10%

common comorbidities:

• depression (50-75%)
• substance misuse (35% in BN, 15% in AN)
• OCD (25% in AN)

Aetiology

• multifactorial: psychological, sociological, and biological associations
• individual: perfectionism, lack of control in other life areas, history of sexual abuse
• personality: anxiety, perfectionism, obsessionality, negative emotionality, cognitive inflexibility
• family & sociocultural: invalidating family structure, prevalent in industrialized societies, idealization of thinness in the media, athletic demands
• puberty
• genetic factors

Risk Factors

• physical factors: obesity, chronic medical illness (e.g. DM)
• psychological factors: individuals who by career choice are expected to be thin, family history (mood disorders, eating disorders, substance use disorder), history of sexual abuse (especially for BN),
• competitive athletes, concurrent associated mental illness (depression, OCD, anxiety disorder (especially panic and agoraphobia), substance use disorder (specifically for BN))

History and Physical

• General History: Eating habits, perception of body image, actual/desired weight, use of laxatives/diet pills, menstrual history, psychiatric history, substance abuse.
• Examination: Complete medical and psychiatric examination, mental status, assessment for suicidality, cognitive status.
• Laboratory Investigations: CBC, electrolytes, renal and liver function tests, calcium, magnesium, phosphate, cholesterol, lipids, amylase, thyroid function tests, urine analysis.
• Other Investigations: Electrocardiogram, chest radiograph.

Specific Disorders

• Anorexia Nervosa: Underweight, fear of weight gain, body image distortion, amenorrhea. Types: Restricting type, Binge-eating/purging type. High mortality rate.
• Bulimia Nervosa: Binge eating followed by compensatory behaviors, normal weight range.
• Binge Eating Disorder: Recurrent binge eating, no compensatory behaviors, associated with obesity risk.
• Avoidant/Restrictive Food Intake Disorder: Lack of interest in food or aversion to certain foods, social function impairment.
• Pica: Craving for non-food items.
• Rumination Disorder: Regurgitation of food after eating.

History

Identifying Abnormal Thinking about Weight, Body Image, Diet, and Exercise:

• Perceptions of healthy weight and desired weight.
• Beliefs about the need to lose more weight.
• Fear of gaining weight.
• Body dissatisfaction and specific areas of concern.
• Eating in front of others and reasons for avoiding it.
• Frequency of weighing oneself.
• Methods used to control weight.
• Types and frequency of exercise, including level of intensity.
• Foods and drinks avoided, and when avoidance began.
• Ritualized eating habits.
• Preference for eating alone.
• Counting calories, fat, and carbohydrates.
• Instances of binge eating, frequency, and types/amounts of food consumed.
• Use of medications or methods to induce vomiting or frequent toileting to control weight.

Family and Social History:

• Family history of obesity, eating disorders, depression, other mental illnesses (especially anxiety disorders and OCD), and substance abuse.
• Social history covering home life, school life, friends, activities, and sexual history.

Menstrual History:

• Age at menarche.
• Regularity of menstrual cycles.
• Last menstrual period.

Additional History:

• Use of cigarettes, drugs, and alcohol (noting that heavy alcohol use increases B vitamin requirements).
• Use of anabolic steroids (particularly in boys).
• Use of stimulants.
• Involvement with pro-anorexia (‘pro-ana’) or pro-bulimia (‘pro-mia’) websites or social media.
• History of trauma.
• Previous therapies (type, duration, and outcomes).

Examination

Pubertal Development:

• Assessment and documentation of pubertal stage.
• Signs of delayed or interrupted pubertal development.

Signs of Recurrent Vomiting/Purging:

• Gingivitis and dental caries (erosion of enamel, gum recession, and friable gums).
• Hypokalaemia and/or elevated bicarb.
• Loss of enamel on surfaces of teeth.
• Callouses on dorsum of the hand (Russell’s sign).
• Subconjunctival haemorrhage.

Mental Health:

• Flat or anxious affect.
• Functional decline.
• Comprehensive risk assessment including suicidality and self-harm.
• Severe family stress or strain.
• Symptoms of depression, anxiety, obsessive-compulsive disorder, or other co-morbid conditions.

Other Features of Severe Malnutrition:

• Lanugo hair.
• Dull, thinning scalp hair.
• Dry skin.
• Skin breakdown and/or pressure sores.
• Bruising/abrasions over the spine related to excessive exercise.
• Muscle wasting (can be proximal and distal).
• Muscle weakness on testing.
• Assess bones carefully, including for lumbar crush fractures.
• Arrhythmias on Electrocardiogram.
• Cardiomyopathy, cardiac failure.
• Postural hypotension.
• Postural tachycardia.
• Bradycardia.
• Peripheral oedema.
• Hypothermia.
• Constipation.
• Amenorrhoea.

Treatment / Management

• Psychotherapy: Enhanced CBT, Family-Based Treatment, Interpersonal Psychotherapy.
• Pharmacotherapy: Fluoxetine for Bulimia Nervosa and Binge Eating Disorder.
• Nutritional Therapy: Caloric intake management, vitamin/mineral supplementation.
• Specific Management Strategies:
  • Anorexia Nervosa: Outpatient/inpatient care based on severity, psychotherapy, antidepressants.
  • Bulimia Nervosa: Inpatient care for severe cases, CBT, antidepressants.
  • Binge Eating Disorder: CBT, antidepressants, anticonvulsants, lisdexamfetamine.
  • Avoidant/Restrictive Food Intake Disorder: CBT for ages >10 years.
  • Pica: Decreasing exposure to craved items, micronutrient supplementation.
  • Rumination Disorder: Biofeedback-guided diaphragmatic breathing, relaxation techniques.

Prognosis

• Variable, better for Bulimia Nervosa than Anorexia Nervosa.
• Influenced by duration, BMI, personality traits, concurrent conditions.

Differential Diagnosis

• Rule out chronic infectious diseases, malabsorptive disorders, malignancies, endocrine disorders.
• Assess for comorbid psychiatric conditions: OCD, depression, anxiety disorders, personality disorders.

• Complications
  • The complications of eating disorders can be classified as acute or chronic physical complications and psychological comorbidities. 
  • Acute Complications
    • Usually correlate with the rate of weight loss. 
    • Cardiovascular
      • bradycardia
      • hypotension
      • arrhythmias
      • pericardial effusion
      • heart failure
      • myocardial fibrosis
      • pulmonary edema
    • Haematological
      • anemia
      • impaired immunity 
    • Cognitive deficits with memory and concentration impairment
    • Peripheral neuropathy
    • proximal myopathy,
    • hepatitis, pancreatitis
    • constipation
    • dental health issues/enlargement of the parotid gland
      • Frequent vomiting associated with eating disorders can cause poor dental health. One-third of bulimia nervosa patients have enlargement of the parotid gland.
    • Hyponatremia
      • can be caused by the use of diuretics, vomiting, and excessive water intake. During the phase of refeeding, hypokalemia is common.
    • Hypophosphatemia
      • Aggressive nutrition therapy could cause a hypophosphatemia-induced refeeding syndrome characterized by rhabdomyolysis, hemolysis, ileus, metabolic acidosis, hypotension, arrhythmias, cardiac failure, seizures, coma, and sudden death.
    • multivitamin deficiency
      • Patients with eating disorders can have a multivitamin deficiency, including thiamine, niacin, vitamin B6, B12, vitamin C, D, E, K, and folate. They can also have iron, zinc, magnesium, and copper deficiency.
    • Anorexia nervosa is complicated by dysregulation of the hypothalamic-pituitary axis causing hypothalamic amenorrhea and dysregulation of hypothalamic-pituitary-adrenal axis causing hypercortisolemia and growth hormone resistance. 
  • Chronic Complications
    • Growth and development may be slowed.
    • Puberty can also be delayed.
    • Eating disorders could cause amenorrhoea in females and impotence in males.
      • If the women with eating disorders become pregnant, she faces a higher rate of obstetric complications.
    • Bone mineral density is decreased, and greater risk for fractures.
    • Binge eating could pose a risk of obesity and type 2 diabetes.
  • Psychiatric Comorbidity
    • Common in eating disorders
      • Anxiety disorders 
      • Depression with suicidal thoughts 
      • Compulsive behaviors, such as
        • skin-picking
        • hair-pulling
        • compulsive exercise 
      • Impulsive behaviors, such as
        • self-harm
        • aggression
        • alcohol use
        • drug use
      • Obsessive-compulsive personality disorder
      • borderline personality disorder
      • avoidant personality disorder
  • Refeeding Syndrome
    • Refeeding syndrome is clinical and metabolic changes arising from aggressive nutritional rehabilitation of a malnourished patient. The most common complication is hypophosphatemia. Fluid overload common in refeeding syndrome. 
    • The following factors help in preventing refeeding syndrome,
      • The initial protein intake should be 1.2 grams per kilogram of ideal body weight per day. 
      • A low-calorie intake of 30 kcal/kilogram/day during the first week
      • Phosphorus should be supplemented to maintain serum levels above 3.0 mg/dL.
    • Monitoring for Refeeding
      • Clinical Monitoring –
        • Continuous cardiorespiratory monitor
        • Focus on cardiac and neurologic
        • Strict intake and output
        • Calorie count
        • Daily weights
      • Biochemical Monitoring (At baseline and at least daily)
        • Measure phosphorus, magnesium, potassium, glucose, sodium, and renal function
        • Zinc and pre-albumin levels are also measured. 
    • Treatment of refeeding syndrome
      • Rehydrate carefully and correct the electrolyte imbalance. 
      • Administer thiamine before feeding at the dose of 100 to 300 mg per day oral or 50 to 100 mg/day intravenous.
      • Start feeding at lower calories of 10 kcal per kg/day and gradually increase over seven day

Criteria for Admission and Readmission

Indicators for Urgent Inpatient Admission for Anorexia Nervosa

• Rapid Weight Loss:
  • 1 kg/week average over 6 weeks.
• Significant Weight Loss:
  • 15% of pre-morbid weight in the last 3-6 months.
• Refusal of Oral Intake.
• Vital Signs:
  • Resting Pulse <50 bpm.
  • Systolic Pressure <80 mmHg.
  • Orthostatic changes in pulse (>20 bpm rise) or BP (>20 mmHg drop).
• Hydration Status:
  • Dehydration or refusal of fluid intake.
  • Ketosis.
• Temperature:
  • Hypothermia (Temp <35.5°C).
  • Cold or blue extremities.
• Cardiovascular:
  • Presence of any arrhythmia on ECG.
  • Prolonged QTc interval >450 msec.
• Electrolyte Abnormalities:
  • Especially Magnesium (Mg²⁺), Phosphate (PO₄³⁻), and Potassium (K⁺).
• Metabolic:
  • Hypoglycemia.
• Psychosocial:
  • Severe family stress and strain.
  • Behaviors related to the eating disorder impacting family functioning.
  • Suicidality or self-harm that cannot be managed in an outpatient setting.

Indicators for Urgent Inpatient Admission for Bulimia Nervosa

• Cardiovascular:
  • Syncope.
  • Cardiac arrhythmias, including prolonged QTc interval >450 msec.
• Serum Electrolytes:
  • Serum potassium <3.2 mmol/L.
  • Serum chloride <88 mmol/L.
• Gastrointestinal:
  • Oesophageal tears.
  • Hematemesis (blood in vomit).
• Temperature:
  • Hypothermia (Temp <35.5°C).
• Vomiting:
  • Intractable vomiting.
• Psychosocial:
  • Severe family stress and strain.
  • Behaviors related to the eating disorder impacting family functioning.
  • Suicidality or self-harm that cannot be managed in an outpatient setting.

Shared Care

Benefits:

• Multidisciplinary approach recommended for effective treatment.
• Improves collaboration, communication, risk management, and recovery outcomes.
• Prevents medical deterioration and excessive admissions.

Roles and Responsibilities:

Community Mental Health Clinician (QH):

• Coordinate the treatment plan and establish shared care with the GP.
• Communicate changes in treatment, forward care reviews, and maintain accurate records.
• Facilitate medical monitoring and upload information to CIMHA.
• Ensure attendance at appointments and facilitate team communication.
• Collaborate with Child Youth Mental Health Services for transitions.

General Practitioner (GP):

• Provide weekly or clinically indicated monitoring, including vital signs and lab tests.
• Review monitoring parameters against QuEDS Indicators.
• Liaise with the treating team if parameters indicate medical admission.
• Essential Monitoring Components:
  • Inquire about fainting, dizziness, chest pain, palpitations, and other symptoms.
  • Ask about food intake, vomiting, exercise, and laxatives.
  • Measure postural heart rate and blood pressure, temperature, weight, and ECG as needed.
  • Regular blood tests: electrolytes, kidney/liver function, serum glucose, and full blood count.
  • Annual bone mineral density scan if indicated.

Patient:

• Schedule and attend appointments with the GP and other specialists.
• Utilize meal plans and supports provided.

Family, Carers, and Supports:

• Recognized as integral members of the treatment team.
• Encourage engagement with non-government support services.

Private Mental Health Practitioner:

• Provide evidence-based psychological therapy and supportive therapy.
• Communicate with the community team regarding the management plan.