What is the best course of treatment for a patient with disordered eating, including underlying psychological issues such as depression or anxiety, and impaired physical health status?

Treatment of Disordered Eating

All patients with disordered eating require a coordinated multidisciplinary treatment plan incorporating medical, psychiatric, psychological, and nutritional expertise, with disorder-specific psychotherapy as the cornerstone of treatment. 1, 2

Initial Assessment and Medical Stabilization

Vital Signs and Physical Examination

• Measure temperature, resting heart rate, blood pressure, orthostatic pulse, and orthostatic blood pressure at every evaluation to detect cardiovascular instability from malnutrition 1, 3
• Document height, weight, and BMI (or percent median BMI for children/adolescents) to quantify nutritional status 1, 3
• Examine for Russell's sign (calluses on knuckles), parotid gland enlargement (swollen cheeks/jawline), dental erosion, and lanugo hair as physical markers of purging or starvation 1, 3

Essential Laboratory Testing

• Obtain complete blood count to detect anemia, leukopenia, and thrombocytopenia from malnutrition 1, 2
• Order comprehensive metabolic panel including sodium, potassium, chloride, bicarbonate, magnesium, phosphate, BUN, creatinine, and liver enzymes to identify electrolyte abnormalities (hypokalemia, hypochloremic alkalosis from purging; hyponatremia from water loading) 1, 2
• Perform electrocardiogram in all patients with restrictive eating or severe purging to assess QTc prolongation, which predicts sudden cardiac death risk 1, 2

Critical caveat: Normal laboratory values do not exclude serious illness—approximately 60% of anorexia nervosa patients show normal routine testing despite severe malnutrition. 1

Psychiatric and Behavioral Assessment

• Screen for suicidality at every visit, as 25% of anorexia nervosa deaths result from suicide 1, 3
• Assess for comorbid depression and anxiety using validated screening measures, as these affect approximately one in four patients with eating disorders 4
• Evaluate the frequency and types of disordered behaviors: restrictive eating, binge episodes, self-induced vomiting, laxative abuse, excessive exercise 3
• Determine whether eating patterns are volitional (true eating disorder) versus driven by physiologic disruption in hunger/satiety cues from metabolic perturbations (disrupted eating) 4

Disorder-Specific Treatment Approaches

Anorexia Nervosa

For adolescents and emerging adults with an involved caregiver, family-based treatment (FBT) is the first-line psychotherapy. 1, 2

For adults, provide eating disorder-focused psychotherapy that normalizes eating behaviors, restores weight, and addresses fear of weight gain and body image disturbance. 1, 2

Nutritional Rehabilitation

• Set individualized weekly weight gain goals of 2.2 to 4.4 lb per week to stabilize cardiovascular health 1, 5
• Establish target weight based on pre-illness growth trajectories and degree of malnutrition 1, 5
• Initiate slow, cautious refeeding with phosphorus supplementation to prevent fatal refeeding syndrome in severely malnourished patients 1
• Consider nasogastric tube or intravenous nutrition if oral intake is insufficient 1

Common pitfall: Do not attempt rapid nutritional rehabilitation, as this increases the risk of fatal refeeding syndrome characterized by ventricular arrhythmias. 1

Cardiac Monitoring

• Monitor QTc intervals serially in patients with ongoing restrictive eating, as prolonged QTc predicts sudden cardiac death 1, 2
• Most cardiac manifestations (bradycardia, QTc prolongation, cardiac muscle atrophy) are completely reversible with appropriate nutritional rehabilitation 1

Endocrine and Bone Health

• Obtain thyroid function tests (TSH, free T4) in patients with oligomenorrhea or amenorrhea 1, 3
• Consider DXA scan for patients with prolonged amenorrhea (>6 months) to assess for osteopenia and osteoporosis 1, 3
• Measure 25-hydroxyvitamin D levels if low bone mineral density or bone stress injury is suspected 1, 3
• Note that hypothyroidism, hypercortisolism, and hypogonadotropic hypogonadism typically resolve with nutritional rehabilitation and do not require specific hormonal treatment 1, 3

Bulimia Nervosa

Adults with bulimia nervosa should receive eating disorder-focused cognitive-behavioral therapy (CBT) combined with fluoxetine 60 mg daily, prescribed either initially or if minimal response to psychotherapy alone occurs by 6 weeks. 1, 2, 6

For adolescents and emerging adults with an involved caregiver, offer family-based treatment. 1, 2

• Fluoxetine 60 mg daily is FDA-approved for bulimia nervosa and specifically targets binge-eating and vomiting behaviors in patients with moderate to severe bulimia (≥3 bulimic episodes per week for 6 months) 6
• The efficacy of fluoxetine 60 mg/day in maintaining response for up to 52 weeks has been demonstrated in placebo-controlled trials 6

Binge-Eating Disorder

Patients with binge-eating disorder should receive eating disorder-focused cognitive-behavioral therapy or interpersonal therapy, delivered in either individual or group formats. 1, 2

For adults who prefer medication or have not responded to psychotherapy alone, prescribe either an antidepressant or lisdexamfetamine. 1, 2, 5

• Lisdexamfetamine is specifically supported by evidence for binge-eating disorder 5
• Topiramate also shows evidence for bulimia nervosa 5

Integration with Comorbid Conditions

Depression and Anxiety

• When a patient with disordered eating is receiving psychological therapy, the behavioral health professional should monitor for disordered eating behaviors using validated measures 4
• Physical activity interventions demonstrate benefits for both depressive symptoms and metabolic control 4
• Internet-delivered CBT shows moderate to large improvements in depressive symptoms at 12 months 4
• Antidepressant medications may treat co-occurring depression but should not be pursued alone without psychotherapy 5

Diabetes and Disordered Eating

• Screen for disordered or disrupted eating using validated measures when hyperglycemia and weight loss are unexplained based on self-reported medication dosing, meal plan, and physical activity behaviors 4
• Review the medical treatment plan to identify potential treatment-related effects on hunger and caloric intake 4
• Reevaluate the treatment plan in consultation with a qualified health professional with expertise in both diabetes disease physiology and disordered eating behaviors 4
• Consider the appropriateness of incretin therapies, which may have potential relevance to treating disrupted or disordered eating 4

Important distinction: Do not label patients as having a diagnosable eating disorder when disordered eating patterns are driven by physiologic disruption in hunger/satiety cues, metabolic perturbations, or secondary distress from inability to control hunger rather than psychological factors. 4

Criteria for Hospitalization

Patients must be medically stabilized in an acute care hospital before transfer to a specialized eating disorder program if they meet criteria for life-threatening medical instability. 1

Indications for Immediate Hospitalization

• Acute food refusal 5
• Uncontrollable binge eating or purging 5
• Severe electrolyte abnormalities (hypokalemia carries risk of fatal arrhythmia) 1
• Significant QTc prolongation 1, 2
• Severe bradycardia or orthostatic instability 1
• Acute suicidality 1, 3
• Acute gastric dilatation or perforation from binge eating 7

Common pitfall: Do not delay hospitalization based on patient or family denial of illness severity, as eating disorders are life-threatening conditions requiring aggressive early intervention. 1

Monitoring Treatment Response

• Reevaluate patients periodically during extended treatment to assess ongoing need for therapy 6
• Remission is indicated by healthy biopsychosocial functioning, cognitive flexibility with eating, resolution of disordered behaviors, and restoration of weight and menses if applicable 5
• Monitor the medical treatment plan in response to reduction in depressive symptoms, as this may affect eating behaviors 4