The Links Between PTSD and Eating Disorders

May 2, 2008
Timothy D. Brewerton, MD
Volume 25, Issue 6

Despite an abundance of studies linking both traumatic experiences and anxiety disorders with eating disorders, relatively little has been reported on the prevalence of associated posttraumatic stress disorder (PTSD) or partial PTSD in patients with eating disorders.

Despite an abundance of studies linking both traumatic experiences and anxiety disorders with eating disorders, relatively little has been reported on the prevalence of associated posttraumatic stress disorder (PTSD) or partial PTSD in patients with eating disorders. The National Women's Study, dating back more than 10 years, remains the only detailed study of crime victimization histories, resultant PTSD, and associated psychiatric comorbidity, including eating disorders, in a representative sample of women in the United States.1 This article presents the case for a link between PTSD and eating disorders. The prevalence of comorbid PTSD and eating disorders is discussed with an explanation of a mechanism that may explain the connection, followed by treatment options and reasons for caution.

Prevalence
In the National Women's Study, both current and lifetime PTSD prevalence were found to be significantly higher in persons with bulimia nervosa than in those without bulimia nervosa (current: 21% vs 4%, P < .001; lifetime: 37% vs 12%, P < .001). Those who met DSM-IV criteria for binge eating disorder also had a significantly higher lifetime prevalence of PTSD (22%) compared with control participants (P < .01), although there was no significant difference in current PTSD prevalence. One of the critical findings from this study was that prevalence of bulimia nervosa was significantly greater in individuals with histories of rape with PTSD (10.4%) than in those with histories of rape without PTSD (2.0%) and in those with no history of rape (2.0%). These findings strongly imply that it is abuse resulting in PTSD (rather than abuse per se) that significantly increases the chances of later developing bulimia nervosa.2 Lifetime PTSD also predicted the associated comorbidities of major depression and alcohol abuse/dependence with bulimia nervosa.3 None of the study participants with anorexia nervosa had a history of PTSD.

Studies of clinical samples also indicate higher than expected rates of PTSD in patients with eating disorders. In one report, 74% of 293 women attending residential treatment indicated that they had experienced a significant trauma, and 52% reported symptoms consistent with a diagnosis of current PTSD based on their responses on a PTSD symptom scale.4 Forty-seven percent of 112 patients with anorexia nervosa and 62% of patients with bulimia nervosa met PTSD criteria. It was not clear from this study what percentage of the anorexia nervosa patients also binged and/or purged. However, taken together, the overall research literature has linked histories of trauma and PTSD with bulimic disorders, including bulimia nervosa, binge eating disorder, and anorexia nervosa of the binge-eating/purging type, as opposed to anorexia nervosa of the restricting type.2,5-9

In a clinical sample of 44 patients who recovered from bulima nervosa, 20 abused patients showed a trend toward more frequent diagnoses of PTSD over their life span and more frequent substance dependence than did the 24 nonabused patients.10 Lipschitz and colleagues11 reported on the associated comorbidity among 74 adolescent inpatients. PTSD was the most common diagnosis (36%), and eating disorders were significantly more frequent in the PTSD group (25%) than in the non-PTSD group (6%, P < .03). In addition, hospitalized adolescent males with PTSD were more likely to have comorbid eating disorders, other anxiety disorders, and somatization. Unfortunately, the types of eating disorders in these patients were not described.

In a large national sample of 24,041 hospitalized female veterans, those inpatients with an eating disorder diagnosis had higher rates of anxiety disorders, especially PTSD, as well as borderline personality disorder (BPD).12 The point prevalence of PTSD in women inpatients with an eating disorder was 25% compared with 8% in inpatients who did not have an eating disorder. The authors noted that there was very little overlap between those with PTSD and BPD in that only 12.5% of the inpatients with BPD also had a diagnosis of PTSD.

In a study of 2436 women at a long-term residential treatment center, the rates of PTSD significantly differed across eating disorder diagnoses (P < .05), with the highest rates occurring in patients with anorexia nervosa binge-eating/purging type (25%) and the lowest rates occurring in patients with anorexia nervosa restricting type (10%). Intermediate PTSD rates were found in those with bulimia nervosa (23%) and in those with eating disorder not otherwise specified (23%).13

Thompson and associates14 investigated rates of PTSD symptoms and other psychopathology in 97 women who: (1) had been sexually abused in childhood only; (2) had been raped in adulthood only; (3) had been both sexually abused during childhood and raped during adulthood; or (4) had never been sexually abused. All participants were assessed using the Structured Clinical Interview for DSM-IV and the Modified PTSD Symptom Scale Self-Report. Women who reported sexual trauma, regardless of age, were significantly more likely to exhibit psychopathology than controls, including higher rates of both PTSD and eating disorders. Rates of PTSD diagnosis were 6 to 7 times higher in the 3 trauma groups than in the control group, and rates of an eating disorder diagnosis were 5 times higher.

In a study of 257 female patients evaluated at an anxiety disorders clinic who had principal diagnoses of an anxiety disorder (PTSD, generalized anxiety disorder, panic disorder, obsessive-compulsive disorder, or so-cial phobia), only PTSD and social phobia were significantly related to eating disorder symptoms. These 2 anxiety disorders accounted for significant, unique variance in eating disorder pathology.15

All of the above studies took place in the United States, where PTSD rates are high; however, 2 studies completed in Europe provided a very different perspective. In Switzerland, Hepp and colleagues16 assessed the frequency of comorbid PTSD in 277 women with DSM-IV-defined eating disorders, including 84 with anorexia nervosa, 152 with bulimia nervosa, and 41 with eating disorder not otherwise specified using the Structured Clinical Interview for DSM-IV.16 None of the participants had current PTSD, and only 4 participants (1.4%) met lifetime criteria for PTSD. However, the authors noted that Switzerland has an extremely low base rate of PTSD in the general population. In a Zurich cohort of over 4500 adults, the 12-month prevalence using DSM-IV criteria was found to be 0% for PTSD, 2.2% for subthreshold PTSD in females, and 0.26% for subthreshold PTSD in males.17

In a study undertaken in Great Britain, 164 consecutive referrals to the Eating Disorders Unit at the Maudsley Trust Hospitals who met criteria for anorexia nervosa (n = 90), bulimia nervosa (n = 54), or eating disorder not otherwise specified (n = 20) were assessed for PTSD using the Structured Clinical Interview for DSM-III-R.18 In the overall sample only 4% met criteria for current PTSD and 11% met criteria for lifetime PTSD. Patients with anorexia nervosa had PTSD rates (10%) similar to those of patients with bulimia nervosa (13%) and those who had eating disorder not otherwise specified (10%).

Reasons for a link
The potential reasons for an association between severe trauma, PTSD, and bulimic disorders, especially bulimia nervosa, have been discussed in detail elsewhere.2,5,8,9 It has been hypothesized that eating disordered behaviors, particularly purging behaviors, serve to facilitate avoidance of traumatic material and to numb the hyperarousal and emotional pain associated with traumatic memories and thoughts. Purging may also promote forgetting parts or all of a traumatic event (ie, dissociative amnesia). Several studies have reported higher rates of dissociative symptoms in bulimic patients than in controls, and in the National Women's Study, 27% of patients with bulimia nervosa endorsed forgetting all or part of traumatic memories compared with 11% of participants who did not have an eating disorder.8 Thus, bulimia often serves as a maladaptive coping strategy in the same way substance abuse does in relationship to trauma and PTSD.2,3,19Treatment
Treatment approaches for PTSD and trauma-related disorders have advanced considerably over the past several years. The most empirically validated treatments for PTSD include cognitive-behavioral therapy (CBT) with prolonged exposure (PE), eye movement desensitization reprocessing (EMDR), and pharmacotherapy,20-25 although CBT with PE appears to be the most effective and long-lasting modality. Psychodynamic psychotherapy that involves the processing of traumatic material may also be useful.24,26 Dialectical behavior therapy can be effective in BPD and other trauma-related diagnoses characterized by affective dysregulation, including PTSD, bulimia nervosa, impulse control disorders, and dissociative disorders.23,25,27-31

There are no published treatment studies or guidelines specifically involving patients with eating disorders and PTSD. The principles of treatment for such patients are based on practice guidelines for the individual conditions. The American Psychiatric Association has published guidelines for both eating disorders and PTSD. An attempt to combine these principles into an integrated approach for the traumatized patient with a comorbid eating disorder has been detailed elsewhere.2,5 In addition, a case formulation approach has been described that can be used to integrate empirically supported treatments for various comorbid conditions, including PTSD and eating disorders.32,33

In the case formulation approach, the clinician applies hypotheses about potential mechanisms that cause and perpetuate dysfunctional behaviors. This is combined with the adoption of empirically validated treatments for each case that includes hypothesis testing and continuous collection of data to assess progress and process. A critical component of this approach is to determine the functional mechanisms that link problem behaviors or disorders.2 In other words, what is the function of the symptom? For example, a common hypothesis is that bulimic behaviors, such as self-induced vomiting and laxative abuse, act to facilitate or promote numbing and avoidance of trauma-related memories, dreams, feelings, thoughts, and behaviors, and decrease or blunt associated hyperarousal.

To the degree that this theory is verified by the patient, this makes way for learning healthier coping strategies to effectively deal with the underlying issues without the adverse consequences. In this integrated line of attack, evidence-based treatments for eating disorders, such as CBT for PTSD, can be woven into a phasic deployment of interventions that are modified to the needs of the individual.

CBT is clearly the most empirically supported form of psychotherapy for eating disorders and for most forms of trauma-related comorbidity, including PTSD, major depression, other anxiety disorders, and substance use disorders. Consequently, CBT has nearly universal application in this highly comorbid group and can serve as the foundation on which other therapeutic interventions may be supplemented, such as interpersonal psychotherapy, pharmacotherapy, family therapy, or psychodynamic psychotherapy.

Although CBT for PTSD has a number of key ingredients, such as anxiety reduction skills training, rec-ord keeping, cognitive therapy, and relapse prevention, the inclusion of prolonged exposure with cognitive reprocessing appears to be critical to the successful resolution of PTSD.21,22,34-36 EMDR seems to include most of these components and can be an acceptable treatment alternative for PTSD.37 Studies indicate that EMDR is as efficacious as CBT with PE as well as fluoxetine, at least in the short term.38,39 More recent comparison studies indicate that CBT with PE may have more lasting benefit than EMDR (B. Rothbaum, unpublished data, January 2008).

Diagnostic issues and complications
There are several issues that may arise in the course of evaluating and treating the traumatized patient with an eating disorder. To some extent, this depends on the level of skill, training, and experience of the clinician, but these patients are challenging to even the most seasoned clinicians. A common mistake made by therapists inexperienced in the treatment of eating disorders is to not fully appreciate the need for nutritional rehabilitation (relative normalization of weight and eating) before beginning actual exposure work. Another error is to fail to properly teach and demonstrate anxiety reduction skills or stress inoculation training before tackling traumas directly. In either case, it is easy for patients to become so overwhelmed with emotionally laden material that they are unable to process physiologically, psychologically, or both, and they, in turn, revert back to their familiar coping methods involving self-destructive but nevertheless numbing and avoidant disordered eating behaviors.

Some clinicians may not be familiar with the empirically based treatments for PTSD and/or bulimia nervosa, particularly CBT, and require specialized supervision and/or training before real progress can be made. In these situations, the clinician would do well to consider making a referral to someone who specializes in this area in order to better serve the patient's needs. Another common mistake is to not continue the "prolonged" exposure long enough until there is true extinction of hyperarousal and avoidance responses. Clinicians who are not versed in behavior therapy may unintentionally and unconsciously collude with the avoidance of the patient.

Vicarious traumatization can be a valid concern for therapists who are doing trauma work, and it is important to acknowledge that patients' recounting of their traumatic experiences may trigger therapists' own issues. The control and processing of both negative and positive countertransference is especially critical in this work given the dangers of retraumatization.

In general, patients will show a relative readiness (or decreased resistance) to commence more intensive trauma work when their eating disorder symptoms are under sufficient control, their brains are being well-nourished (thereby normalizing neurotransmitter function),40 and they have mastered some anxiety reduction skills. Patients are consequently much better able to adequately process painful experiences and integrate them emotionally and cognitively.

Given the significant trust issues that these patients often have, it is common for them to not feel safe enough to disclose abuse or important details about their abuse until they have progressed well into their course of therapy. Previous threats to patients made by perpetrators not to disclose abuse may remain operative in the form of maladaptive beliefs. As a result, an occasional re-assessment of any relevant trauma history can be productive.

It is important to note that once nutritional and weight stabilization occurs, delayed PTSD may emerge de novo or previously diagnosed PTSD may get worse in the absence of the patient's usual avoidance and numbing strategies. Sometimes patients do not begin to even recognize that they have been abused until the precise definitions of abuse and neglect have been explained to them. Once their cognitive set changes in such a way that they can perceive past traumatic experiences as abusive, delayed PTSD symptoms may appear. Recovering patients may even remember earlier traumatic events or significant details of events that they had previously forgotten once full nutritional stabilization has taken place and they feel safer, stronger, and more supported.

It is important for therapists to contain any "rescue" fantasies that they may harbor and refrain from using techniques designed to recover memories, such as hypnosis or amobarbital interviews, because these are fraught with dangers such as the induction of false memories. Traumatized eating disorder patients may be particularly vulnerable to this given their high degree of hypnotizability.41 In addition, if any previous traumatic events are reported by patients, it is imperative that clinicians recognize and observe all reporting laws mandated by their discipline and national, state, and local governments.
 

References:

References


1. Dansky BS, Brewerton TD, Kilpatrick DG, O'Neil PM. The National Women's Study: relationship of crime victimization and posttraumatic stress disorder to bulimia nervosa. Int J Eat Disord. 1997;21:213-228.
2. Brewerton TD. Eating disorders, victimization and comorbidity: principles of treatment. In: Brewerton TD, ed. Clinical Handbook of Eating Disorders: An Integrated Approach. New York: Marcel Dekker, Inc; 2004:509-545.
3. Dansky BS, Brewerton TD, Kilpatrick DG. Comorbidity of bulimia nervosa and alcohol use disorders: results from the National Women's Study. Int J Eat Disord. 2000;27:180-190.
4. Gleaves DH, Eberenz KP, May MC. Scope and significance of posttraumatic symptomatology among women hospitalized for an eating disorder. Int J Eat Disord. 1998;24:147-156.
5. Brewerton TD. Eating disorders, trauma, and comorbidity: focus on PTSD. Eat Disord. 2007;15:285-304.
7. Brewerton TD. Bulimia in children and adolescents. Child Adolesc Psychiatr Clin N Am. 2002;11:237-256.
8. Brewerton TD, Dansky BS, Kilpatrick DG, O'Neil PM. Bulimia nervosa, PTSD and "forgetting": results from the National Women's Study. In: Trauma and Memory. Williams LM, Banyard VL, eds. Thousand Oaks, CA: Sage Publications; 1999:127-138.
9. Brewerton TD, Dansky BS, O'Neil PM, Kilpatrick DG. Relationship between "purging disorder" and crime victimization in the National Women's Study. Poster presented at: 9th Annual Meeting of the Eating Disorders Research Society; October 1-4, 2003; Ravello, Italy.
10. Matsunaga H, Kaye WH, McConaha C, et al. Psychopathological characteristics of recovered bulimics who have a history of physical or sexual abuse. J Nerv Ment Dis. 1999;187:472-477.
11. Lipschitz DS, Winegar RK, Hartnick E, Foote B, et al. Posttraumatic stress disorder in hospitalized adolescents: psychiatric comorbidity and clinical correlates. J Am Acad Child Adolesc Psychiatry. 1999;38:385-392.
12. Striegel-Moore RH, Garvin V, Dohm FA, Rosenheck RA. Eating disorders in a national sample of hospitalized female and male veterans: detection rates and psychiatric comorbidity. Int J Eat Disord. 1999;25:405-414.
13. Blinder BJ, Cumella EJ, Sanathara VA. Psychiatric comorbidities of female inpatients with eating disorders. Psychosom Med. 2006;68:454-462.
14. Thompson KM, Wonderlich SA,Crosby RD, Mitchell JE. Sexual victimization and adolescent weight regulation practices: a test across three community based samples. Child Abuse Negl. 2001;25:291-305.
15. Becker CB, DeViva JC, Zayfert C. Eating disorder symptoms among female anxiety disorder patients in clinical practice: the importance of anxiety comorbidity assessment. J Anxiety Disord. 2004;18:255-274.
16. Hepp U, Spindler A, Schnyder U, et al. Post-traumatic stress disorder in women with eating disorders. Eat Weight Disord. 2007;12:24-27.
17. Hepp U, Gamma A, Milos G, et al. Prevalence of exposure to potentially traumatic events and PTSD. The Zurich Cohort Study. Eur Arch Psychiatry Clin Neurosci. 2006;256,151-158.
18. Turnbull SJ, Troop NA, Treasure JL. The prevalence of post-traumatic stress disorder and its relation to childhood adversity in subjects with eating disorders. Eur Eat Disord Rev. 1997;5:270-277.
19. Brady KT, Killeen TK, Brewerton T, Lucerini S. Comorbidity of psychiatric disorders and posttraumatic stress disorder. J Clin Psychiatry. 2000;61(suppl 7):22-32.
20. The Expert Consensus Panels for PTSD. The expert consensus guidelines series. Treatment of posttraumatic stress disorder. J Clin Psychiatry. 1999;60(suppl 16)3-76.
21. Foa EB, Rothbaum BO. Treating the Trauma of Rape: Cognitive-Behavioral Therapy for PTSD. New York: Guilford Press; 1998.22. Ballenger JC, Davidson JR, Lecrubier Y, et al. Consensus statement on posttraumatic stress disorder from the International Consensus Group on Depression and Anxiety. J Clin Psychiatry. 2000;61(suppl 5):60-66.
23. Robertson M, Humphreys L, Ray R. Psychological treatments for posttraumatic stress disorder: recommendations for the clinician based on a review of the literature. J Psychiatr Pract. 2004;10:106-118.
24. Ursano RJ, Bell C, Eth S, et al. Practice guideline for the treatment of patients with acute stress disorder and posttraumatic stress disorder. Am J Psychiatry. 2004;161(suppl 11):3-31.
25. Ross CA. A proposed trial of dialectical behavior therapy and trauma model therapy. Psychol Rep. 2005;96:901-911.
26. Sherman JJ. Effects of psychotherapeutic treatments for PTSD: a meta-analysis of controlled clinical trials. J Traum Stress. 2003;11:413-435.
27. Becker CB, Zayfert C. Integrating DBT-based techniques and concepts to facilitate exposure treatment for PTSD. Cogn Behav Pract. 2001;8:107-122.
28. Bradley RG, Follingstad DR. Group therapy for incarcerated women who experienced interpersonal violence: a pilot study. J Traum Stress. 2003;16:337-340.
29. House AS. Increasing the usability of cognitive processing therapy for survivors of child sexual abuse. J Child Sex Abus. 2006;15:87-103.
30. Spoont MR, Sayer NA, Thuras P, et al. Practical psychotherapy: adaptation of dialectical behavior therapy by a VA Medical Center. Psychiatr Serv. 2003;54:627-629.
31. Marcus MD, Levine MD. Use of dialectical behavior therapy in the eating disorders. In: Brewerton TD, ed. Clinical Handbook of Eating Disorders: An Integrated Approach. New York: Marcel Dekker; 2004:473-488.
32. Zayfert C, Becker CB. Cognitive-Behavioral Therapy for PTSD: A Case Formulation Approach. New York: Guilford Press; 2007.
33. Persons JB. Empiricism, mechanism, and the practice of cognitive-behavior therapy. Behav Ther. 2005;36:107-118.
34. Foa EB, Keane TM, Friedman MJ; International Society for Traumatic Stress Studies, eds. Effective Treatments for PTSD: Practice Guidelines from the International Society for Traumatic Stress Studies. New York: Guilford Press; 2000.
35. Deblinger E, Heflin AH. Treating Sexually Abused Children and Their Nonoffending Parents: A Cognitive Behavioral Approach. Thousand Oaks, CA: Sage Publications; 1996.
36. Resick PA, Schnicke M. Cognitive Processing Therapy for Rape Victims: A Treatment Manual. Newbury Park, CA: Sage Publications; 1993.
37. Shapiro F. Eye Movement Desensitization and Reprocessing: Basic Principles, Protocols, and Procedures). 2nd ed. New York: Guilford Press; 2001.
38. Rothbaum BO, Astin MC, Marsteller F. Prolonged exposure versus eye movement desensitization and reprocessing (EMDR) for PTSD rape victims. J Traum Stress. 2005;18:607-616.
39. van der Kolk BA, Spinazzola J, Blaustein ME, et al. A randomized clinical trial of eye movement desensitization and reprocessing (EMDR), fluoxetine, and pill placebo in the treatment of posttraumatic stress disorder: treatment effects and long-term maintenance. J Clin Psychiatry. 2007;68:37-46.
40. Brewerton TD, Steiger H. Neurotransmitter dysregulation in anorexia nervosa, bulimia nervosa and binge eating disorder. In: Brewerton TD, ed. Clinical Handbook of Eating Disorders: An Integrated Approach. New York: Marcel Decker Inc; 2004:257-281.
41. Pettinati HM, Horne RL, Staats JM. Hypnotizability in patients with anorexia nervosa and bulimia. Arch Gen Psychiatry. 1985;42:1014-1016.