What psychiatric diagnoses are commonly co-morbid with eating disorders?

Common Psychiatric Comorbidities with Eating Disorders

Eating disorders are most commonly comorbid with depression, anxiety disorders (particularly obsessive-compulsive disorder), and substance use disorders, with more than 70% of people with eating disorders experiencing at least one psychiatric comorbidity. 1

Primary Psychiatric Comorbidities

Mood Disorders

• Depression: Present in approximately 49.5% of patients with anorexia nervosa, 76.3% with bulimia nervosa, and 65.5% with binge-eating disorder 2
• Increased suicide risk (particularly in anorexia nervosa, where 25% of deaths are from suicide) 2

Anxiety Disorders

• Present in >50% of eating disorder patients 1
• Most common anxiety comorbidities include:
  • Obsessive-compulsive disorder (28.8% in children with eating disorders) 3
  • Generalized anxiety disorder (lifetime prevalence estimated at 19.5%) 4
  • Social anxiety disorder 5
  • Panic disorder 5
  • Post-traumatic stress disorder 5
  • Specific phobias 4

Other Common Comorbidities

• Personality disorders: Present in >53% of eating disorder patients 1
• Substance use disorders: Present in >10% of eating disorder patients 1
• Attention deficit/hyperactivity disorder: Present in 47.9% of children with eating disorders 3
• Disruptive/impulse control disorders: Present in 45% of children with eating disorders 3

Assessment Considerations

When evaluating patients with eating disorders, the American Psychiatric Association recommends:

1. Comprehensive psychiatric evaluation to identify co-occurring psychiatric disorders 4
2. Screening for anxiety in people exhibiting anxiety or worries regarding eating behaviors that interfere with self-management 4
3. Annual screening for depressive symptoms in all patients with eating disorders, especially those with a self-reported history of depression 4
4. Assessment for trauma history, as adverse experiences can affect symptom perception and treatment response 4

Clinical Implications

Bidirectional Relationship

• Having an eating disorder increases the risk of developing other psychiatric disorders:
  • After anorexia nervosa diagnosis, median hazard ratio for subsequent psychiatric disorders is 3.80 6
  • After other eating disorder diagnoses, median hazard ratio is 3.16 6
• Having a psychiatric disorder increases the risk of developing an eating disorder:
  • Median hazard ratio of 2.66 for developing anorexia nervosa after a psychiatric disorder 6
  • Median hazard ratio of 2.51 for developing other eating disorders after a psychiatric disorder 6

Treatment Considerations

• Important principle: Recognize the effect of starvation and unstable eating on both the diagnosis and response to treatment of comorbidities 5
• Psychiatric comorbidities may be present before, during, or develop in the long-term course of eating disorders 1
• Avoidant-restrictive food intake disorder is a contraindication for restrictive dietary therapy in patients with irritable bowel syndrome 4

Age-Specific Considerations

• In children aged 9-10 years with eating disorders, the most common comorbidities are:
  • Anxiety disorders (71.4%)
  • ADHD (47.9%)
  • Disruptive/impulse control disorders (45.0%)
  • Mood disorders (29.6%)
  • OCD (28.8%) 3

Clinical Pitfalls to Avoid

• Overlooking comorbidities: Comprehensive assessment is essential as comorbidities are present in >70% of cases 1
• Misattribution of symptoms: Some symptoms may overlap between eating disorders and other psychiatric conditions (e.g., changes in appetite, sleep, and motivation in depression) 4
• Underestimating suicide risk: Particularly in anorexia nervosa, where mortality rate is nearly 6 times higher than age-matched controls 2
• Focusing only on eating behavior: Psychosocial assessment should include evaluation of functioning at home, school, and with friends 4

Understanding and addressing these comorbidities is essential for comprehensive treatment planning and improving outcomes in patients with eating disorders.