Eating Disorders & Co-Occurring Psychiatric Disorders (Dual Diagnosis)

Eating disorders frequently co-occur with psychiatric conditions such as anxiety, depression, OCD, PTSD, and personality disorders, which can exacerbate symptoms. Understanding dual diagnosis is essential for those seeking treatment, as co-occurring conditions often share underlying traits like impulsivity and obsessive behaviors. Comprehensive treatment approaches, including psychoeducation and psychotherapy, can help individuals manage both their eating disorder and coexisting mental health conditions for improved outcomes.

Eating Disorders & Co-occurring Mental Health Conditions

Research shows that up to 95% of people diagnosed with an eating disorder also receive a diagnosis for at least one other psychiatric disorder, known as dual diagnosis. The most common co-occurring psychiatric disorders with eating disorders include:¹

• Anxiety disorders, affecting up to 62% of those with eating disorders¹
• Mood disorders, affecting up to 54% of those with eating disorders¹
• Trauma- and stress-related disorders, affecting up to 27% of those with eating disorders¹
• Substance use disorders, affecting up to 27% of those with eating disorders¹
• Obsessive-compulsive and related disorders
• Personality disorders
• Neurodevelopmental disorders

Non-suicidal self-injury and suicidality are also common in patients with eating disorders and can be compounded by multiple psychiatric diagnoses.¹

Anxiety Disorders

Social anxiety disorder

Social anxiety disorder (SAD) is a disproportionate fear or anxiety regarding social situations, with common situations including social interactions, being observed or performing.²

Up to 42% of individuals with anorexia nervosa will experience symptoms that meet clinical criteria for social anxiety disorder (SAD).³ Appearance anxiety in particular may contribute to disordered eating.

Generalized anxiety disorder

Generalized anxiety disorder (GAD) is excessive anxiety and worry about a number of events or activities with difficulty controlling the worry.²

Up to 30% of those with anorexia nervosa and bulimia nervosa have co-occurring generalized anxiety disorder (GAD).⁴ Eating disorders and GAD share similar clinical features, like overwhelming anxiety which may present in eating disorders around weight gain and body shape.

Mood Disorders

Major depressive disorder

Major depressive disorder (clinical depression) consists of a depressed mood and/or loss of interest alongside other symptoms.²

Clinical depression is one of the most common co-occurring diagnoses with eating disorders, with up to 75% of individuals with an eating disorder also experiencing symptoms of depression.^1,5 

Eating disorders and clinical depression have significant overlap in emotional presentation, including:

• Low self-esteem
• Body dissatisfaction
• Low self-worth or inadequacy
• Loneliness and isolation
• Feeling out of control, angry or irritable

Bipolar disorder

Two common bipolar disorders associated with eating disorders are:²

• Bipolar I Disorder, when a patient experiences at least one manic episode that requires hospitalization or marked impairment in social or occupational function, with or without being preceded or followed up by hypomanic or depressive episodes
• Bipolar II Disorder, when a patient experiences one hypomanic episode and at least one major depressive episode and no manic episodes

During manic or hypomanic episodes, individuals can go into an impulsive state and struggle with self-control and have difficulty listening to their body, either by ignoring hunger cues or exercising to the point of exhaustion.

In a depressive episode, food might be used as a coping mechanism, bingeing to stimulate dopamine release in the brain and eating past the point of fullness to prolong this feeling.

Trauma and Stress-related Disorders (Post-traumatic Stress Disorder)

Post-traumatic stress disorder (PTSD) can develop after experiencing or witnessing a traumatic event, such as:²

• Combat
• Natural disasters
• Serious or life-threatening accidents
• Assault or abuse

Around 24% of those with bulimia nervosa and anorexia nervosa have PTSD and least 52% of those with an eating disorder diagnosis have a history of trauma, with traumatic events often taking place before the onset of an eating disorder.⁶ Those with eating disorders may use disordered eating behaviors as a way to cope with their trauma.

Substance Use Disorders

Both disordered eating and substance use can be utilized to cope with negative emotion states. Substance use disorders (SUDs) – a problematic pattern of substance use that affects a patient’s health and wellbeing – are significantly more common in individuals who participate in purging behaviors, affecting up to 27% of those with eating disorders.^1,2,10 Patients may also turn to substance use, particularly methamphetamines or cocaine, to lose weight because some drugs can suppress appetite and make restriction easier.

Obsessive-compulsive & Related Disorders (Obsessive-compulsive Disorder)

Obsessive-compulsive disorder (OCD) is characterized by persistent, unwanted thoughts (obsessions) and repetitive behaviors or mental acts (compulsions) that patients feel compelled to perform.²

Obsessions or compulsions are time consuming and often cause distress, significantly impacting quality of life. The symptomology of OCD can be frequently seen in eating disorders, like:

• Obsession around weight loss
• Repeated measuring, weighing or body checking
• Food-related rituals

Up to 44% of those with anorexia nervosa and atypical anorexia nervosa and up to 33% of those with bulimia nervosa also have OCD.^7,8

Personality Disorders

Obsessive compulsive personality disorder

Obsessive compulsive personality disorder (OCPD) is a pervasive pattern of preoccupation with orderliness, perfectionism and mental and interpersonal control at the expense of flexibility, openness and efficiency.²

Many of the characteristics of OCPD are mirrored in eating disorder pathology. A preoccupation with details, rules, order and schedules reinforces disordered eating behaviors like:

• Strict calorie and micronutrient counting
• Rigid exercise schedules
• Precision dieting
• Extreme dedication to achieving lower weights or specific measurements.

Borderline personality disorder

Borderline personality disorder (BPD) is a pervasive pattern of instability of interpersonal relationships, self-image and affects with marked impulsivity.² The prevalence of BPD is more common in patients with anorexia nervosa binge purge subtype (AN-BP) and bulimia nervosa, at 25% and 28% respectively.⁹

The impulsivity categorized by BPD is easily mirrored in impulsive eating pathology, including purging methods like self-induced vomiting and misuse of diuretics and laxatives.

Neurodevelopment Disorders

Attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is a persistent pattern of inattention and/or hyperactivity and impulsivity that interferes with functioning and development.² It is characterized by symptoms of inattention and/or hyperactivity that are inappropriate for developmental level.

Impulsivity and inattention are shared features of both bulimia nervosa and ADHD, with research suggesting that the occurrence of ADHD is higher in patients with bulimia nervosa.¹¹

Autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by persistent deficits in social communication and interactions, restricted interests and repetitive behavior.² Nearly 23% of individuals with ASD have an eating disorder.¹²

ASD shares some symptomology with both anorexia nervosa¹² and avoidant restrictive food intake disorder (ARFID).

Restricted and intense focus on specific interests can be limited to or directed toward food and diet, and rigid attitudes can manifest through weight-focused repetitive behaviors, like body checking or weighing oneself.

Food selectivity is the most frequent eating problem in children with ASD and being a picky eater, aversions to specific characteristics of foods and rigid brand preference can cause those with ASD to become underweight. 

Effective Treatment for Eating Disorders & Co-occurring Conditions

Dual diagnosis treatment is crucial because it can help treat conditions that may be contributing to an eating disorder. Eating disorders and co-occurring diagnoses can compound each other, making it equally important to treat all diagnoses. By treating both conditions simultaneously, individuals can learn healthier ways to manage their symptoms and improve their outcomes.

Psychoeducation

Psychoeducation can help those with dual diagnoses understand the connection between their multiple diagnoses. Psychoeducation is a therapeutic intervention that teaches patients about their mental health conditions and treatment. Being able to understand one’s diagnoses and learning how conditions can be managed empowers patients to be an active and informed participant in their care.

Psychotherapy

Psychotherapy is a critical intervention for those with dual diagnoses. Research continually shows around 75% of those who receive psychotherapy experience some symptom relief.¹³ Psychotherapy has been shown to improve emotional and psychological wellbeing and is linked with positive changes in the brain and body.

Learn more about psychotherapy options for eating disorders.

Find Help for Dual Diagnosis

Living with both an eating disorder and another mental health condition can feel especially overwhelming, but you don’t have to navigate it alone. Integrated care that addresses both conditions at the same time is essential for lasting recovery. With the right support team and evidence-based treatment, recovery is possible.

References

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2. American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Arlington, VA.
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4. Halmi, K. A. (1991). Comorbidity of psychiatric diagnoses in anorexia nervosa. Archives of General Psychiatry, 48(8), 712. https://doi.org/10.1001/archpsyc.1991.01810320036006
5. Harney, M. B., Fitzsimmons-Craft, E. E., Maldonado, C. R., & Bardone-Cone, A. M. (2013). Negative affective experiences in relation to stages of eating disorder recovery. Eating Behaviors, 15(1), 24–30. https://doi.org/10.1016/j.eatbeh.2013.10.01
6. Blais, R. K., Brignone, E., Maguen, S., Carter, M. E., Fargo, J. D., & Gundlapalli, A. V. (2017b). Military sexual trauma is associated with post‐deployment eating disorders among Afghanistan and Iraq veterans. International Journal of Eating Disorders, 50(7), 808–816. https://doi.org/10.1002/eat.22705
7. Levinson, C. A., Brosof, L. C., Ram, S. S., Pruitt, A., Russell, S., & Lenze, E. J. (2019). Obsessions are strongly related to eating disorder symptoms in anorexia nervosa and atypical anorexia nervosa. Eating Behaviors, 34, 101298. https://doi.org/10.1016/j.eatbeh.2019.05.001
8. Matsunaga, H., Kiriike, N., Miyata, A., Iwasaki, Y., Matsui, T., Fujimoto, K., Kasai, S., Kaye, W. H., & Kaye, W. H. (1999). Prevalence and symptomatology of comorbid obsessive–compulsive disorder among bulimic patients. Psychiatry and Clinical Neurosciences, 53(6), 661–666. https://doi.org/10.1046/j.1440-1819.1999.00622.x
9. Sansone, R. A., Levitt, J. L., & Sansone, L. A. (2004). The Prevalence of Personality Disorders Among Those with Eating Disorders. Eating Disorders, 13(1), 7–21. https://doi.org/10.1080/10640260590893593
10. Devoe, D. J., Dimitropoulos, G., Anderson, A., Bahji, A., Flanagan, J., Soumbasis, A., Patten, S. B., Lange, T., & Paslakis, G. (2021). The prevalence of substance use disorders and substance use in anorexia nervosa: a systematic review and meta-analysis. Journal of Eating Disorders, 9(1). https://doi.org/10.1186/s40337-021-00516-3
11. Reinblatt, S. P. (2015). Are Eating Disorders Related to Attention Deficit/Hyperactivity Disorder? Current Treatment Options in Psychiatry, 2(4), 402–412. https://doi.org/10.1007/s40501-015-0060-7
12. Huke, V., Turk, J., Saeidi, S., Kent, A., & Morgan, J. (2013). Autism Spectrum Disorders in Eating Disorder Populations: A Systematic Review. European Eating Disorders Review, 21(5), 345–351. https://doi.org/10.1002/erv.2244
13. What is Psychotherapy? (n.d.). https://www.psychiatry.org/patients-families/psychotherapy