People with eating disorders commonly experience other mental health disorders prior to, during, or following the development of an eating disorder. When another disorder is present at the same time, the problems are referred to as a “co-occurring” disorder or a “dual diagnosis.” Depression, anxiety, alcohol use disorders (AUDs) and substance use disorders (SUDs) commonly occur alongside eating disorders, with estimates ranging from 17 to 46%. Among those with eating disorders, alcohol is the most common substance use problem, followed by cannabis and cocaine. Having a dual diagnosis is associated with worse eating disorder symptoms, a more difficult, longer recovery process; serious medical consequences; and higher rates of suicide and mortality. This makes early and effective identification and treatment of both disorders crucial.
Why Do These Disorders Commonly Overlap?
It is likely that some of the same biological, psychological, and social factors that make a person susceptible to developing an eating disorder may increase the risk for developing substance use disorders. However, some research suggests different genetic pathways for the development of eating disorders and SUDs. Some theories of eating disorders suggest that people engage in disordered eating as a method of mood regulation or coping with negative emotion. Alcohol and/or substances may serve a similar purpose for those with both problems. People may also use substances like caffeine, nicotine, and stimulants to control weight and provide energy in the context of an eating disorder. Impulsivity may also make someone more likely to develop an eating disorder such as bulimia or a SUD. Other risk factors include childhood physical or sexual abuse and a lifetime history of depression.
The hallmark characteristic of anorexia nervosa is body weight and shape control, typically through restricting energy intake and also through compensatory behaviors such as excessive exercise or purging (vomiting, laxative misuse). There is an approximately 13% chance that someone with anorexia will develop a SUD. Those patients with anorexia who also binge and purge are more likely to develop an AUD or SUD than those with the purely restricting type. However, people with anorexia may take stimulants such as caffeine, nicotine, insulin, or thyroid medications to suppress appetite in order to facilitate weight loss.
Bulimia Nervosa and Binge Eating Disorder (BED)
Across the board, higher frequency of binge eating and purging is associated with more frequent substance use. Someone with bulimia has an approximate 34% chance of developing a substance use disorder and those with binge eating disorder have an estimated 20% chance. As previously mentioned, people with a binging or purging disorder often do so in order to cope with, lessen, or escape negative emotions. Abusing alcohol and substances can serve the same purpose and may serve as a maladaptive way of coping with the guilt and shame that follows binging and/or purging.
Assessment and Treatment of Addictions and Eating Disorders
People with alcohol and SUDs and eating disorders usually need professional treatment to recover. Individuals with eating disorders who also present with a SUD typically have worse symptoms, serious medical complications, longer recovery times, higher rates of suicide/suicide attempts, and higher mortality rates. Some patients with co-occurring disorders may be able to recover with outpatient treatment, but hospitalization, partial hospitalization, residential treatment or intensive outpatient treatment may be necessary depending on medical complications and severity.
With up to half of individuals with an eating disorder reporting SUDs, clinicians treating patients with either eating disorders or SUDs should always screen and assess for both SUDs and eating disorders. A full medical and psychological evaluation should be completed to determine the nature and severity of any given presenting problem, and to determine whether medical stabilization is necessary. Patients may be reluctant to report symptoms of eating disorders and/or SUDs, and they may be resistant to beginning treatment. As such, it is important for clinicians to obtain collateral information from family members and/or friends familiar with the patient.
For patients with anorexia who have critically low weight, heart irregularities, or electrolyte imbalances, hospitalization or nutritional rehabilitation may be necessary. Patients who are engaging in laxative abuse require the immediate cessation of this behavior and the associated withdrawal may require medical management. It may also be necessary to detox a patient from alcohol or a substance before the therapeutic process can begin.
Treating one disorder without addressing the other can be problematic. It is impossible to engage fully in eating disorder treatment if a person is intoxicated during treatment sessions, and regular substance abuse outside of sessions can undermine the treatment process. Treatment directly addressing both issues is important because the development of an eating disorder may facilitate or maintain the symptoms of a substance use disorder and vice/versa.
Symptom substitution can occur when an individual, through treatment, begins to rely less on eating disorder symptoms such as binging and purging as coping mechanisms and instead relies more on alcohol or drug use to cope with situations that would typically trigger eating disorder symptoms. Alternatively, someone in recovery from alcohol or drug addiction may turn to disordered eating as a method of mood regulation or stress management if adaptive coping strategies are not implemented. For this reason, clinicians should continue to assess symptoms of both disorders over the course of the treatment process.
There is not a lot of research on the treatment of co-occurring alcohol/SUDs specifically. Overall, treatment programs that address both problems simultaneously are ideal, with individual, group, and family therapy provided by an interdisciplinary team. A cognitive behavioral therapy (CBT) approach is the most well-researched treatment for eating disorders, and motivational interviewing (MI) is an effective intervention for alcohol and substance use disorders. Dialectical behavior therapy (DBT) has shown to be effective at targeting both problems as it addresses the emotional and behavioral difficulties that are observed in both eating disorders and substance use disorders. Engagement in a 12-step program (e.g., AA, NA) concurrently with eating disorder treatment may also be effective. When patients complete an inpatient or residential treatment stay, ongoing individual or group therapy, support groups, or ongoing participation in a 12-step program can aid in relapse prevention.
It is imperative that professionals who treat eating disorders and AUDs/SUDs be aware of how common and dangerous these problems are alone, and especially when they are co-occurring. Risk factors include childhood trauma, a history of depression and/or ADHD, family and personal history of substance use/misuse, impulsivity, and purging behaviors. Any patient presenting for treatment for either a SUD or eating disorder should be thoroughly screened for the presence of a co-occurring disorder. Individuals with addictions and eating disorders have the greatest chance of recovery with simultaneous treatment from a multidisciplinary treatment and support team.
This is a great source of information on co-occurring disorders and dual diagnosis.
Bahji, A., Mazhar, M. N., Hawken, E., Hudson, C. C., Nadkarni, P., & MacNeil, B. A. (2019). Prevalence of Substance Use Disorder Comorbidity among Individuals with Eating Disorders: A Systematic Review and Meta-Analysis. Psychiatry Research.
Gregorowski, C., Seedat, S., & Jordaan, G. P. (2013). A clinical approach to the assessment and management of co-morbid eating disorders and substance use disorders. BMC Psychiatry, 13(1), 289.
Harrop, E. N., & Marlatt, G. A. (2010). The comorbidity of substance use disorders and eating disorders in women: Prevalence, etiology, and treatment. Addictive Behaviors, 35(5), 392-398.
Woodside, B. D., & Staab, R. (2006). Management of psychiatric comorbidity in anorexia nervosa and bulimia nervosa. CNS Drugs, 20(8), 655-663.
Written by Dr. Elisha Carcieri, 2019