The impact of borderline personality disorder on process group outcome among women with posttraumatic stress disorder related to childhood abuse

The outcome of a 12-week interpersonal process group therapy for women with postraumatic Stress Disorder (PTSD) related to childhood sexual abuse with and without borderline personality disorder (BPD) was assessed by comparing three naturally occurring treatment conditions: Groups that did not have any members with borderline personality disorder (BPD-) (n = 18), groups in which at least one member carried the diagnosis (BPD+)(n = 16), and a 12-week waitlist (WL) (n = 15). PTSD, anger, depression, and other symptoms were significantly reduced in the BPD- groups. However, the BPD+ and WL conditions did not show any pre- to posttreatment improvements. Furthermore, the BPD+ condition showed a significant worsening on measures of anger. Analyses within the BPD+ condition indicated that women with and without the diagnosis experienced equal posttreatment increases in anger problems. These latter results suggest the presence of an anger "contagion" effect. That is, women without BPD did well in the BPD- groups but showed increased anger similar to the BPD+ women when treated in groups with them. Implications for client-treatment matching considerations in PTSD group therapy are discussed.