Objective: The primary aim of the present study was to examine whether the presence of borderline personality disorder (BPD) adversely impacted on outcome 3 years after treatment among women with bulimia nervosa (BN), in comparison to those women with either other personality disorders (other PD) or no personality disorder (no PD).
Method: Participants were 134 women who received cognitive behaviour therapy for BN. The sample was divided into three groups: BPD (n=38), other PD (n=37), and no PD (n=59). Eating disorder (ED) symptoms and attitudes, and personality traits were examined at pretreatment assessment, 1 year and 3 year follow up.
Results: At pretreatment assessment the BPD group had higher purging frequency, more comorbidity and poorer general functioning than the other PD and no PD groups. By 3 year follow up, however, no significant differences were found in ED symptomatology and general functioning among the groups. Pretreatment differences between the BPD and no PD groups on the personality measures of harm avoidance, self-directedness and cooperativeness disappeared over the course of 3 years.
Conclusion: Although women with BN and comorbid BPD appear more impaired at pretreatment assessment, they do not have poorer outcome than the other PD and no PD groups. The rate and level of improvement across the groups is not affected by the presence of BPD.