Research indicates that a diagnosis of borderline personality disorder (BPD) is associated with poorer outcomes in the treatment of many Axis I disorders, including major depression (e.g., Ilardi, Craighead, & Evans, 1997
), obsessive-compulsive disorder ( Baer et al., 1992
), bulimia nervosa (e.g., Ames-Frankel et al., 1992
), and substance abuse (e.g., Verhuel, van den Brink, & Hartgers, 1998
). In addition, BPD is often an exclusion criterion in studies examining treatments for Axis I disorders. This contributes to the widespread notion that individuals with BPD will not benefit from treatments for Axis I conditions.
This is particularly problematic in the field of posttraumatic stress disorder (PTSD) because of the high rates of comorbidity between BPD and PTSD. In one study of 379 participants presenting with BPD, 61% of females and 35% of males also met diagnostic criteria for PTSD ( Zanarini et al., 1998
). Examined from the other direction, 76% of a small sample of male Vietnam combat veterans with PTSD had a comorbid diagnosis of BPD ( Southwick, Yehuda, & Giller, 1993
). Many studies demonstrate similarly high rates of comorbidity between PTSD and BPD (e.g., Allen, Huntoon, & Evans, 1999
; Golier et al., 2003
; Hyer, Woods, & Boudewyns, 1991
; Shea, Zlotnick, & Weisberg, 1999
; Sherwood, Funari, & Piekarski, 1990
). In spite of the significant overlap between PTSD and BPD, research has shown that the addition of BPD does not significantly alter the symptom presentation of PTSD and vice versa ( Zlotnick, Franklin, & Zimmerman, 2002
; Zlotnick et al., 2003
), suggesting that patients with both disorders do not appear to have a more severe clinical presentation than individuals with only one of these disorders.
There is, however, lingering concern that borderline symptomatology may impede progress in cognitive-behavioral treatment (CBT) for PTSD. Clinical lore suggests that the potentially high rates of anger, aggression, and self-harm typically present in those with more severe borderline personality pathology may interfere with intensive CBT methods such as exposure and cognitive restructuring of core schemas. In fact, two studies document deleterious effects of comorbid BPD on treatment retention and outcome. In a study of group CBT outcome, Cloitre and Koenen (2001)
found that groups with at least one member with comorbid BPD showed (a) no change in PTSD and depression and (b) higher rates of anger and anger problems than groups without members with BPD. These results suggest that a diagnosis of BPD mitigates the effects of CBT for PTSD for both participants with BPD and without BPD when administered in a group setting. Another study compared individual CBT to individual present-centered therapy for female survivors of childhood sexual abuse and found that all women with a comorbid BPD diagnosis ( n
=4) dropped out of CBT, whereas no one with BPD dropped out of the present-centered treatment ( McDonagh et al., 2005
). McDonagh and colleagues conclude that CBT may not be well tolerated among individuals with “more complex clinical presentations” such as BPD.
A study examining the impact of borderline personality characteristics
(BPC) on treatment outcome for chronic PTSD, however, found that women with BPC were able to benefit significantly from CBT ( Feeny, Zoellner, & Foa, 2002
). The study examined the effects of BPC on outcome in 72 female victims of sexual and physical assault participating in one of three treatment conditions (prolonged exposure, stress inoculation training, and a combination treatment condition). There were no significant differences in the dropout rate between BPC and non-BPC groups. Additionally, no significant posttreatment differences were found for PTSD diagnosis and severity, depression, state anxiety, trait anxiety, or social functioning. There was, however, a significant difference on end-state functioning scores, with only 11% of participants with BPC meeting criteria for good end-state functioning compared to 51% of participants without BPC. Thus, women with BPC demonstrated significant gains from CBT for PTSD despite greater overall impairment at the end of treatment than their non-BPC counterparts.
The aims of the current investigation were to further examine and clarify the effect of borderline personality characteristics on treatment outcome for PTSD. To do this, we sought to replicate and expand upon the findings of Feeny and colleagues (2002)
by widening the scope of relevant outcome variables to include trauma-related symptoms and by using a larger sample of women in two different CBT treatments. The sample in the present study included 131 treatment-seeking female rape victims with PTSD drawn from a larger treatment outcome study ( Resick, Nishith, Weaver, Astin, & Feuer, 2002
). In addition to PTSD symptomatology, we examined changes in depression and trauma-related sequelae often associated with borderline features (e.g., dissociation, anger). Finally, we used hierarchical linear modeling as a means of determining whether severity of BPC was related to pretreatment scores on various measures as well as whether severity of BPC affected rates of change as a result of treatment and through follow-up.
We hypothesized that participants with higher BPC scores would report higher levels of PTSD symptomatology, consistent with the extant literature. Second, in accordance with the findings of Feeney et al. (2002)
, we hypothesized that participants with higher BPC scores would demonstrate improvement in therapy but that they would not fare as well in terms of overall outcome as individuals with lower BPC scores. Because little is known about whether one type of PTSD treatment is more effective for individuals with a high degree of borderline symptomatology, exploratory analyses were conducted to determine if type of treatment influenced the relationship between BPC and outcome. Findings from this study have several implications for the inclusion of women with BPC in PTSD treatment outcome studies and will help refine our understanding of the specific effects of BPC on response to CBT for PTSD. With such high rates of comorbidity between PTSD and borderline personality features, it is essential to empirically explore the widespread, albeit largely unsupported, belief that those with a high degree of BPC cannot benefit from treatments for PTSD.