Eating Disorders

Lecture Objectives

  • Compare the prevalence, goals of therapy, and clinical characteristics of anorexia nervosa, bulimia nervosa, and binge eating disorder.

  • Describe the diagnostic criteria and clinical findings associated with anorexia nervosa, bulimia nervosa, and binge eating disorder.

  • Discuss treatment approaches for the management of anorexia nervosa, bulimia nervosa, and binge eating disorder.

Overview

  • Disturbance in eating or eating-related behaviors

  • Results in altered consumption or absorption

  • Impair health + psychosocial function

  • Third most common chronic illness in adolescents

  • 5-10 million women, 1 million men

    • Men → 10% anorexia/bulimia, 30% binge eating

  • Rating scales:

    • EAT-26

      • Patient-rated scale

      • Assess symptoms + attitudes characteristics of eating disorders

      • Score > 20 refer for diagnostic interview

    • SCOFF

      • 5-item questionnaire

      • Screens for presence of eating disorders

      • Score > 2 positive responses requires further questioning

Anorexia Nervosa

  • Defined as caloric restriction and low body weight, intense fear of gaining weight, distorted perception of body image

  • Background:

    • Lifetime prevalence - 0.5-2%

    • 1 out of every 200 females

    • Typically adolescence or young adulthood

  • Characteristics:

    • Lack insight into degree of weight loss

    • Social withdrawal, irritability, perfectionims

    • Ritualistic, obsessive, restrictive behaviors

  • Comorbidities:

    • Depression, anxiety, OCD

  • Diagnostic Criteria:

    • Restricting energy intake → Low body weight

    • Fear of gaining weight

    • Disturbance in body weight perception → Influence on self worth or denial of seriousness of low body weight

    • Severity of low body weight

      • Mildly severe: > 17 kg/m²

      • Moderately severe: 16-16.99 kg/m²

      • Severe: 15-15.99 kg/m²

      • Extremely severe: < 15 kg/m²

  • Affect on Body:

    • Brain/Nerves → Impaired cognition, fear of gaining weight, sad, moody, irritable, fainting, changes in brain chemistry

    • Hair → Thinning and brittle

    • Heart → Low blood pressure, slow heart rate, palpitations, heart failure

    • Blood → Anemia

    • Muscles, Joints, Bones → Weak muscles, swollen joins, bone loss, fractures, osteoporosis

    • Kidneys → Kidney stones/failure

    • Body Fluids → Low potassium, magnesium, sodium

    • Intestines → Constipation, bloating

    • Hormones → Periods stop, trouble getting pregnant, higher risk for miscarriage, c-section, baby with low birthweight, postpartum depression

    • Skin → Bruises, dry skin, fine hair all over body, get cold easily, yellow skin, brittle nails

  • Clinical Course:

    • Remission rates near 80%; 20% remain chronically ill

  • Mortality:

    • Highest mortality rate among psychiatric disorders

    • Starvation-related effects, purging-related arrhythmias, suicide

  • Treatment Goals:

    • Weight restoration

    • Nutritional rehab

    • Manage physical complications

    • Reduce distorted body image

    • Manage psychiatric comorbidities

    • Prevent relapse

  • Nutritional Rehabilitation:

    • First-line along with psychotherapy

    • Normalize eating patterns + perceptions of hunger + satiety

    • Restores weight gradually to avoid refeeding syndrome

    • Weight gain:

      • Inpatient → 2-3 lbs/week

      • Outpatient → 0.5-1 lbs/week

    • Improves mood/anxiety, restores gonadal function, restores menses

  • Refeeding Syndrome:

    • Complication of aggressive re-feeding the severely malnourished

    • Shifting from catabolic to anabolic → Triggers insulin secretion

    • Results in dramatic electrolyte shifts (i.e. hypophosphatemia)

    • Complications: arrhythmias, heart failure, seizures

  • Psychotherapy:

    • First-line along with nutrition

    • Addresses distorted body image and dysfunctional eating

    • I.e. Family/group based, cognitive behavioral

  • Pharmacotherapy:

    • NOT initial or primary treatment

    • Reserved until weight restored

    • No FDA approved medications

    • No medications target food-restricting behaviors

  • Select Pharmacologic Considerations:

    • Avoid caffeine to prevent arrhythmias

    • Greater sensitivity to anticholinergic + cardiovascular effects

    • Hypoalbuminemia leads to more unbound medication → More active drug

  • Selective Serotonin Reuptake Inhibitors (SSRIs):

    • SSRIs preferred due to tolerability and safety profile → Start after weight has been established

    • Not for weight gain, ineffective with severe malnourishment

    • Used for depression/anxiety that persists despite weight restoration

    • Med trial of 6-12 months, re-evaluate

  • Bupropion:

    • Contraindicated in eating disorders and seizures

    • Electrolyte abnormalities increase seizure risk

  • Tricyclic Antidepressants (TCAs):

    • I.e. Amitriptyline, imipramine, fluoxetine

    • Generally avoided, anticholinergic activity, arrhythmia risk

  • Second Generation Antipsychotics (i.e. Olanzapine):

    • Severe symptoms interfering with treatment engagement

    • Benefits in body weight + cognitive symptoms are mixed

    • Low doses

    • Monitor QT interval and electrolytes to lessen arrhythmia risk

  • Other Pharmacologic Agents:

    • Bloating, gas → Simethicone; AVOID metoclopramide

    • Constipation → Osmotic laxatives, stool softeners; AVOID stimulant laxatives (i.e. Senna)

    • Anxiety → Hydroxyzine, benzodiazepines prior to meals

    • Multiple medications investigated to improve bone health

Bulimia Nervosa

  • Defined as recurrent episodes of binge eating, compensatory behaviors, distorted body image, normal/weight body habits

  • Background:

    • Lifetime prevalence 0.9-3%

    • Affects. 4-6 out of every 200 females

    • Onset typically adolescence or young adulthood

  • Characteristics:

    • Loss of control over food restriction

    • Triggered by dysphoric mood states

    • 1-20 episodes per day

  • Comorbidities:

    • Depression + anxiety

    • Substance use + impulse-control disorders

    • Borderline personality disorders

  • Diagnostic Criteria:

    • Recurrent episodes

    • Inappropriate compensatory behaviors to prevent weight gain

    • Binging + compensatory behaviors at least weekly for 3 months

    • Self-worth influenced by body weight + shape

  • Compensatory Behaviors:

    • Purging: vomiting, misuse of diuretics, laxatives, enemas

    • Non-purging: fasting/strict dieting, excessive exercise

    • Other: thyroid medication, omitting insulin doses

  • Affects on Body:

    • Brain → Depression, fear of gaining weight, anxiety, dizziness, shame, low self-esteem

    • Cheeks → Swelling, soreness

    • Mouth → Cavities, enamel erosion, gum disease, sensitivity to hot/cold foods

    • Throat/Esophagus → Sore, irritated, tear + rupture, blood in vomit

    • Heart → Irregular heart beat, weakened muscles, heart failure, low pulse/blood pressure

    • Blood → Anemia

    • Muscles → Fatigue

    • Kidneys → Problems from diuretic abuse

    • Body Fluids → Dehydration, low potassium, magnesium, and sodium

    • Intestines → Constipation, irregular bowel movements, bloating, diarrhea, cramping

    • Hormones → Irregular or absent period

    • Stomach → Ulcers, pain, rupture, delayed emptying

    • Skin → Abrasion of knuckles, dry skin

  • Clinical Course:

    • Symptoms wax + wane

    • 50% recover with treatment

    • Mortality rate ~ 1%

  • Treatment Goals:

    • Decrease binge eating + purging

    • Nutritional rehabilitation

    • Manage psychiatric comorbidities + physical complications

    • Prevent relapse

  • Nutritional Rehabilitation:

    • First line

    • Restore structured + consistent meal pattern

    • Adequate nutrition prevents cravings + promotes satiety

  • Psychotherapy:

    • First line

    • Decreased binge/purge frequency

  • Pharmacotherapy:

    • Can be used as an adjunct

    • Fluoxetine = 60 mg/day

    • Antidepressants are first-line → Used if no response to psychotherapy

    • Assess when medication administration occurs with regard to vomiting

  • Antidepressants:

    • SSRIs preferred, high doses, 6-12 months

    • Decrease binging + purging, treat psychiatric comorbidities

    • Bupropion contraindicated

  • Topiramate:

    • Alternative treatment, not first-line option

    • Decreases binge/purging frequency; possible weight loss

    • ADR: cognitive symptoms, paresthesias, kidney stones

Binge Eating Disorder

  • Defined as frequent episodes of binge eating accompanied by sense of loss of control

  • Background:

    • Lifetime prevalence 2-3.5%

    • More common than anorexia or bulimia nervosa

    • Young adulthood

  • Characteristics:

    • Binging without compensatory behaviors

    • Eat quickly until uncomfortably full or when not hungry

    • Repeated history of weight gain and loss

  • Comorbidities:

    • Psychiatric comorbidities

    • 50% have > 3 psychiatric comorbidities

    • Anxiety, mood, substance use disorder

  • Diagnostic Criteria:

    • Recurrent episodes with no compensatory behaviors

    • > 3 of the following:

      • Eating more rapidly than normal

      • Eating large amounts when not hungry

      • Eating until uncomfortably full

      • Feelings of disgust, guilt, depression

      • Eating alone due to embarassment

    • Marked distress

    • Occurs at least weekly for 3 months

  • Obesity:

    • NOT the same conditions

    • Most patients with obesity do not engage in recurrent binge eating

    • Most patients with binge eating disorder have BMI less than 30 kg/m²

  • Treatment Goals:

    • Reduce binge eating

    • Nutritional rehabilitation

    • Treat comorbidities

    • Weight loss

  • Nutritional Rehabilitation:

    • Weight control programs incorporating low-calorie diets

    • Supports weight loss and promotes reduction in binge-eating

  • Psychotherapy:

    • Cognitive behavioral therapy is most effective

  • Pharmacotherapy:

    • Used as an adjunct to psychotherapy

    • Lisdexamfetamine

      • Psychostimulant

      • 50-60 mg/day

      • Adverse effects, misuse potential

    • Other treatment options similar to bulimia nervosa

  • Antidepressants:

    • SSRIs preferred, used at higher dosage range

    • Decreases binge frequency, treat psychiatric comorbidities

  • Topiramate:

    • Decreases binge frequency, possible weight loss

    • ADR: cognitive impairment, paresthesias, kidney stones