Posttraumatic Stress Disorder and Eating Disorders

Although posttraumatic stress disorder (PTSD) often brings to mind combat-related injury, PTSD can affect anyone with a history of physical, emotional, or sexual abuse, or being exposed to a variety of traumatic experiences. PTSD may also lead to eating disorders.

Disordered eating behaviors may represent an individual’s methods for coping with the uncomfortable emotions and experiences correlated with all types of trauma. After trauma, she may begin restricting food intake as a way of feeling in control and by doing so may gain a false sense of security. Or, she may binge-eat as a way to seek comfort through food and to “stuff down” negative feelings. 

Dr. Tim Brewerton, Clinical Professor of Psychiatry and Behavioral Sciences at the Medical University of South Carolina, Charleston, an expert in PTSD and eating disorders, has noted that disordered eating behaviors, especially purging, may be used as an avoidance mechanism by individual to numb painful feelings and to block or forget painful memories. About 10% of women will develop PTSD at some time in their lifetime (Arch Gen Psychiatry 1995; 52:1048).  

In related findings, recent research at the San Francisco VA Medical Center has shown that rates of eating disorders are significantly higher among returning female veterans with comorbid mental health problems compared with those without mental health diagnoses (Women’s Health Issues 2012; 22:e403).

A Major Study Lays Important Groundwork

Fifteen years ago, researchers in the National Women’s Study evaluated a representative sample of more than 3000 women who were interviewed at length about their traumatic experiences. More than half of those meeting diagnostic criteria for bulimia nervosa (BN) reported having been raped, molested, or physically assaulted; fewer than a third of those without eating disorders had experienced such traumas (Int J Eat Disord 1997; 21:2130218).  Dr. Brewerton, one of the authors of that study, pointed out that in 84% of cases the first rape preceded the first binge-eating episode, establishing assault as a potentially contributing if not causative factor for the development of BN. Similar results were found for molestation and physical assault. He reported that 37% of women with BN also had full-blown histories of PTSD, and many more had partial PTSD syndromes.

Psychologist Matthew T. Tull, PhD, associate professor and director of anxiety disorders research at the University of Mississippi Medical Center, Jackson, conducts research on anxiety disorders centering around PTSD and substance abuse. He and his colleagues have reported that those with PTSD are three times more likely to develop bulimic behavior than those who do not have PTSD. And, according to Dr. Jacqueline M. Hirth and her colleagues at the University of Texas Medical Branch, Galveston, nearly a third of U.S. women have experienced traumatic experiences related to intimate partner violence during their lifetimes and two-thirds of these women will develop at least some symptoms of PTSD. Others have shown that patients with PTSD after childhood sexual abuse and a co-occurring eating disorder can develop body image disorders. The results of one study show for the first time that the behavioral component of body image is impaired in female patients with PTSD in addition to the cognitive-affective component. This is not solely due to a comorbid eating disorder (Psychopathology 2012; Sept. 7 [Epub ahead of print]. Few studies have examined the mediating effect of depressive symptoms and PTSD; in a recent study researchers in France found that PTSD symptoms fully mediated the effects of early adult sexual assault on disordered eating, and depressive symptoms were a partial mediator of this relationship (J Trauma Stress 2012; 25:50; doi 10.1002/1002/jts.21664.)

Shame is another component. As Dr. Brewerton has pointed out, trauma-related shame is a major feature of trauma-related conditions, and the reaction of mothers to their daughters’ disclosure of abuse is a powerful predictor of subsequent PTSD and other post-traumatic problems. When the abused person’s story is believed and he or she receives an empathetic, supportive, accepting and nonjudgmental response, the patient can better deal with the traumatic events,  and a more favorable outcome results. In contrast, when the victim is challenged about the trauma, and not believed or doubted, this can aggravate shame, self-loathing (including loathing directed at the body), and can lead to a much poorer outcome.

PTSD among AN patients

When a large study, the NIH-sponsored Genetics of Anorexia Nervosa Collaborative Study, evaluated 753 women with AN, 13.7% (103) met DSM-IV criteria for PTSD (Psychosom Med 2011; 73: 291).  In pairwise comparisons across AN subtypes, the odds of having a PTSD diagnosis were significantly lower in individuals with restricting AN (RAN) than individuals with purging AN without binge eating (PAN) (OR=0.49, 95% CI=0.30, 0.80). The majority of participants with PTSD reported that the first traumatic event occurred before the onset of AN (64.1%, n=66). The most common traumatic events reported by those with a PTSD diagnosis were sexually related traumas during childhood (40.8%) and during adulthood (35.0%).

 Most participants with PTSD reported the first traumatic event before the onset of AN, and the most common traumatic events reported were sexual-related trauma during childhood (40.8%) and during adulthood (35.0%). However, the participants had experienced a wide range of traumatic events. The authors made an important point, the importance of assessing a history of trauma and possible PTSD among patients with AN.

Dr. Brewerton and others have also noted that certain elements have an impact on the success of treatment, including adequate nutritional rehabilitation, with normalization of weight and eating before any exposure work begins.

– MKS