Eating Disorders
Related Subjects:
|Psychiatric Emergencies
|Personality Disorders
|Eating Disorders
|SCOFF questionnaire screening tool
|SUSS test for eating disorder examinations
🍽️ About Eating Disorders
- Eating disorders are serious psychiatric conditions involving abnormal eating behaviours, weight preoccupation, and body image disturbance.
- They can cause life-threatening complications and require early recognition and multidisciplinary care.
- Most common in adolescents and young adults, but can affect all ages and genders.
🔎 Types of Eating Disorders
🥗 Anorexia Nervosa
- Definition: Restricted energy intake, intense fear of weight gain, distorted body image.
- Subtypes:
- Restricting type – dieting, fasting, excessive exercise.
- Binge/purge type – binge eating + vomiting/laxatives/diuretics.
- Risks: ⚡ Electrolyte imbalance, amenorrhoea, osteoporosis, arrhythmias, sudden cardiac death.
🍩 Bulimia Nervosa
- Definition: Binge eating with compensatory behaviours (vomiting, laxatives, fasting, over-exercise).
- Diagnosis: ≥1 binge/purge episode per week for ≥3 months.
- Risks: ⚡ Hypokalaemia, dental erosion, oesophageal tears, cardiac arrhythmias.
🍔 Binge Eating Disorder
- Definition: Recurrent binge eating without compensatory behaviours.
- Diagnosis: ≥1 episode per week for ≥3 months, associated with rapid eating, discomfort, guilt.
- Risks: Obesity, type 2 diabetes, hypertension, metabolic syndrome.
⚠️ Risk Factors
- 🧬 Genetic predisposition / family history.
- 🧠 Psychological traits – low self-esteem, perfectionism, OCD traits, anxiety/depression.
- 🌍 Social pressures – thin-ideal culture, social media, weight stigma.
- 📉 Dieting and body dissatisfaction.
- 🚨 Childhood trauma or abuse.
🧑⚕️ Clinical Presentation
- Weight loss (anorexia) or fluctuation (bulimia/binge ED).
- Preoccupation with food, calories, body shape.
- Secretive eating, avoidance of social meals.
- Physical: bradycardia, hypotension, lanugo, hair loss, amenorrhoea.
- Bulimia clues: 🖐️ Russell’s sign (knuckle calluses), 🦷 dental enamel erosion.
🧪 Investigations
- 💉 Bloods: FBC, U&E, LFT, TFT, glucose – monitor nutritional/electrolyte status.
- 📈 BMI & growth charts (esp. in adolescents).
- 🩺 ECG: Check for QT prolongation/arrhythmias.
- 🦴 DEXA scan: In long-standing anorexia → osteoporosis risk.
🛠️ Management (Multidisciplinary)
- Psychological therapy:
- 🧠 CBT-E (enhanced CBT): First-line for bulimia, binge ED; effective for anorexia.
- 👨👩👧 Family-Based Therapy (FBT): Recommended in adolescents with anorexia.
- DBT or psychodynamic therapy may be helpful in selected cases.
- Medical monitoring: Regular review of weight, vitals, labs; admit if unstable (per MARSIPAN/NICE red-flag criteria).
- Pharmacotherapy:
- 💊 SSRIs (e.g. fluoxetine) – reduce binge/purge in bulimia; also for comorbid depression.
- ❌ Avoid antidepressants in underweight anorexia (arrhythmia risk, poor efficacy).
- Nutritional rehabilitation: Gradual refeeding, dietitian input, monitor for refeeding syndrome (check phosphate, magnesium, potassium).
- Support systems: Family, peer groups, education about relapse prevention.
📈 Prognosis
- Early intervention improves outcomes and reduces relapse risk.
- ⚠️ Anorexia nervosa has the highest mortality of any psychiatric disorder (malnutrition, cardiac arrest, suicide).
- Bulimia → chronic relapsing course, but treatment responsive.
- Binge eating disorder → better response to therapy but relapse possible.
🔗 References
🍽️ Eating Disorders – Clinical Cases
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Case 1 – Anorexia Nervosa (Restricting Type)
A 19-year-old university student is referred by her GP for significant weight loss.
She exercises excessively and eats only fruit and black coffee, insisting she feels “fat.”
BMI is 15.8 kg/m², pulse 48 bpm, BP 90/60 mmHg.
Bloods show low potassium and amenorrhoea for 8 months.
She denies bingeing or purging.
Teaching point: Anorexia nervosa features restriction of intake, intense fear of weight gain, and body image distortion.
Management: multidisciplinary approach - medical monitoring, psychological therapy (CBT-E, family therapy), and nutritional rehabilitation.
Hospitalisation if BMI < 15, bradycardia, or electrolyte imbalance.
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Case 2 – Bulimia Nervosa
A 24-year-old woman presents with dental enamel erosion and swollen parotid glands.
She reports episodes of binge eating followed by self-induced vomiting “to stay in control.”
BMI is normal (22 kg/m²).
She admits to using laxatives and over-exercising after binges.
Teaching point: Bulimia nervosa involves recurrent binge–purge cycles with preoccupation about weight.
Physical signs include calloused knuckles (Russell’s sign), electrolyte imbalance, and metabolic alkalosis.
Treatment: CBT-E (enhanced cognitive behavioural therapy) and fluoxetine (60 mg/day) if moderate to severe.
-
Case 3 – Binge-Eating Disorder (BED)
A 42-year-old man with obesity (BMI 36 kg/m²) describes recurrent episodes of eating large quantities of food “until uncomfortably full,” without purging.
He feels shame and loss of control afterwards.
Past history of low mood and childhood emotional abuse.
Teaching point: BED is characterised by recurrent binges without compensatory behaviour.
It is the most common eating disorder and strongly associated with obesity, depression, and metabolic syndrome.
Treatment: CBT-E, structured eating plans, and weight management; SSRIs may reduce binge frequency.
💡 Clinical pearl: Always assess physical risk - bradycardia, hypotension, electrolyte disturbance, or prolonged QT.
Eating disorders are psychiatric but can be life-threatening medical illnesses.
Early, compassionate, multidisciplinary care dramatically improves outcomes. 🌿
