Q & A: Borderline Personality Disorder

Q: I’m treating a patient with bulimia nervosa who also appears to have borderline personality disorder. I’m having a great deal of difficulty treating this patient, and I’m trying to use elements of dialectical behavior therapy (DBT) in addition to usual cognitive behavioral therapy (CBT). I’m also having the patient see a psychiatrist for medications. Is there any information on how well or how poorly this patient is likely to do in treatment? (LW, Chicago)

A: Many experts have noted that the treatment of patients with bulimia nervosa who have comorbid borderline personality disorder (BDP) is complicated, and prognosis has been reported as less favorable than for bulimic patients without BPD. For many of these patients, programs combining eating disorders focused treatment including DBT and medication management along the lines that you’ve described are being employed and clinically tested.

One recent longitudinal study compared the course and outcome of 290 inpatients with eating disorders and BPD with 72 eating disorder patients with other axis II diagnoses; both groups were followed every two years for a 10-year period. Although the prevalence of anorexia nervosa (AN), bulimia nervosa (BN), and eating disorder not otherwise specified (EDNOS) declined significantly over time for those in both study groups, the prevalence of EDNOS remained significantly higher among those with BPD. Notably in this study, over 90% of BPD patients who met criteria for AN, BN, or EDNOS at baseline experienced a stable remission by the time of the 10-year follow-up, a source of some comfort to patients and clinicians. However, diagnostic migration was common, particularly for those with AN or BN (IJED 2010; 43:226).

— JY