Women with bulimia nervosa are three times more likely to struggle with PTSD than women without eating disorders, according to a study by Dansky and colleagues (1997). In that study, 37% of individuals with bulimia nervosa had lifetime PTSD, compared to 12% of women without eating disorders. That’s almost two in five.
Treating eating disorders is hard, but treating eating disorders with comorbid conditions is way harder. There is no consensus, it seems, as to what disorder(s) to treat first, or whether they should be treated simultaneously:
Brewerton (2004) suggests that eating problems should be addressed prior to treating PTSD because bingeing and purging contribute to a state of physical and emotional dysregulation. Fairburn (2008), however, suggests that significant comorbid disorders be treated prior to beginning CBT for eating disorders.
The issue is quite complex,
For example, the presence of severe depression, of which hopelessness and difficulty concentrating are core criteria, may present a barrier to treatment of the eating disorder. Furthermore, if eating is used to escape from or avoid intrusive memories or strong emotions, it may be more difficult to treat the disordered eating symptoms without addressing the PTSD first. The treatment approach may then depend upon the conceptualization of the comorbid relationship between PTSD and the eating disorder and their overlapping symptoms.
Personally, I don’t think there needs to be a consensus. The answer will vary for every person. (The gut reaction that EDs must be treated first because of their physical consequences doesn’t apply to everyone. Certainly, substance dependence can be more dangerous.) But there’s no doubt that in most cases, even if the treatment of one disorder is prioritized initially, in the end, treatment needs to be comprehensive and deal with everything.
Wouldn’t it be great, though, if one treatment or therapy could help both disorders simultaneously?
With disorders that have a lot of overlap in associated features and symptoms, such as PTSD and bulimia nervosa, there is reason to believe that treatments that lead to improvements in one disorder would improve the other as well.
WHAT ARE THESE COMMON FEATURES?
Emotion dysregulation, impulsivity, and alexithymia (difficulty in identifying and describing one’s emotions) are common among PTSD and bulimia nervosa sufferers.
In PTSD, emotional dysregulation may be related to “hyperarousal, anger, avoidance, and emotional numbing” (Litz & Gray, 2002). Similarly, in bulimia nervosa, bingeing and purging may be a mechanism by which individuals attempt to regulate negative affect and anxiety. The attempt to over-regulate one’s emotional state through avoidance seems to be present in both disorders.
Impulsivity in particular is associated with both bingeing and purging (I’ve written about that here) and PTSD (Miller & Resick, 2007).
Deficits in interoceptive awareness (the ability to distinguish between feelings and sensations) and alexithymia are also associated with PTSD and eating disorders. (To be more precise, IA has been studied in trauma, not PTSD.) This suggests that perhaps the same vulnerabilities that predispose an individual to develop an eating disorder (or bingeing and purging in AN or BN) also predispose them to PTSD.
COGNITIVE BEHAVIOURAL THERAPY & COGNITIVE PROCESSING THERAPY
Cognitive behavioural therapy (CBT) is considered an evidence-based treatment for bulimia nervosa. Similarly, an adaptation of CBT, called cognitive processing therapy (CPT, more on it here), is commonly used to treat PTSD. Briefly, the focus of these therapies is on learning to recognize and identify maladaptive thoughts and beliefs, and then gaining the skills necessary to challenge them and ultimately alter behaviour.
So…. could treating one disorder help with symptoms of the other, too?
In this study, the authors hypothesized that a decrease in PTSD symptoms following CPT treatment would be associated with “improvements in interoceptive awareness, impulse regulation, and disordered eating attitudes/behaviors.” In other words, treating PTSD will improve features commonly associated with bulimia nervosa.
Looking at the raw data for the psychometric tests assessing PTSD and eating disorders, though the numbers decreased from pretreatment to posttreatment for things like interoceptive awareness, ineffectiveness, and impulse regulation, the decreases were not dramatic. (The posttreatment values still fell within the standard deviation of the pretreatment scores.)
Nonetheless, improvements on the Posttraumatic Stress Diagnostic Scale were significantly associated with decreases in both PTSD and eating disorders (as assessed by the Eating Disorder Inventory-2).
The current report found that mean scores on most [Eating Disorder Inventory 2] subscales were significantly lower at posttreatment relative to baseline, although some of these changes were relatively small. Further, reductions in Interoceptive Awareness, Interpersonal Distrust, Impulse Regulation, Ineffectiveness, and Maturity Fears scores were associated with change in PTSD symptom scores over the course of treatment. Thus, CPT contributes to decreases in symptoms common to both PTSD and eating disorders, although specific eating behaviors were not impacted.
The authors hypothesized that a component of CPT, such as the focus on identifying thoughts/feelings and how those thoughts lead to negative emotions and behaviours, would be helpful in treating those components of bulimia nervosa, all of which makes sense to me.
Taken together, results support the hypothesis that PTSD/eating disorder comorbidity is due, at least in part, to their common symptoms, e.g., emotion dysregulation, impulsivity, and deficits in interoceptive awareness/alexithymia.
It is possible that some women in this study used bingeing and purging to cope with their PTSD symptoms; however, bulimia scores did not significantly decrease following treatment. Because standard CPT does not specifically address disordered eating behaviors, more therapy may be needed to achieve statistically and clinically significant change for specific attitudes and behaviors.
All of which means that in a clinical setting, deciding which disorder to treat first may become less and less of an issue. To me, this makes intuitive sense, particularly for disorders that are characterized by similar symptoms/underlying cognitive processes. Of course, treating patients with comorbid PTSD and BN, will require PTSD-specific and BN-specific treatments, but at least in the beginning, both can be tackled (not necessarily in equal degrees) at once. After all, mental health disorders don’t occur in a vacuum, they are intertwined.
Because this research was a secondary analysis from a previous study and because the researchers only began administering the EDI-2 after the study began, the sample size is quite small (65 individuals). Another big issue is that there is no control group: no group with comorbid PTSD and BN that did not receive the CPT treatment (again, this is because it is a re-analysis of a study that asked a different question). Moreover, the study only focused on interpersonal trauma (such as abuse, rape, torture) and not other types of trauma (for example, vehicle accident), which may limit the generalizability of the findings.
Finally, the sample was limited to women, and the average age was 35 (range between 18 – 74). In terms of ethnicity, 62% were Caucasian, 34% African American, 1.3% were American Indian/Alaskan Native, 0.7% were Asian, and 2% identified as other.
The authors acknowledge these limitations and conclude with acknowledging that this is only the beginning,
Finally, this study was the first to examine the impact of PTSD treatment on symptoms common to both PTSD and eating disorders. However, this is only a small step toward investigation of treatment approaches for these comorbid disorders. Future research should continue to explore the comorbidity of PTSD and eating disorders among diverse groups.
I must admit, it is unsettling that there’s so little research (it seems) on treating comorbid conditions in eating disorder patients. How generalizable are the findings from a sample with no/limited comorbidities when that’s not the reality in a clinical setting?
Thoughts? What do you think about treating EDs with comorbid disorders like PTSD? If you have comorbid disorders, what has helped or hindered your recovery process from both/either?
Mitchell, K.S., Wells, S.Y., Mendes, A., & Resick, P.A. (2012). Treatment improves symptoms shared by PTSD and disordered eating. Journal of Traumatic Stress, 25 (5), 535-42 PMID: 23073973