Differences between patients with borderline personality disorder who do and do not have a family history of bipolar disorder.

Diagnostic confusion sometimes exists between bipolar disorder and borderline personality disorder (BPD). To improve the recognition of bipolar disorder researchers have identified nondiagnostic factors that point toward bipolar disorder. One such factor is the presence of a family history of bipolar disorder. In the current report from the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project, we compared the demographic, clinical, and psychosocial characteristics of patients with BPD who did and did not have a family history of bipolar disorder. A large sample of psychiatric outpatients were interviewed with semi-structured interviews. Three hundred seventeen patients without bipolar disorder were diagnosed with DSM-IV borderline personality disorder. Slightly less than 10% of the 317 patients with BPD (9.5%, n=30) reported a family history of bipolar disorder in their first-degree relatives. There were no differences between groups in any specific Axis I or Axis II disorder. The patients with a positive family history were significantly less likely to report excessive or inappropriate anger, but there was no difference in the frequency of other criteria for BPD such as affective instability, impulsivity, or suicidal behavior. The patients with a positive family history reported a significantly higher rate of increased appetite and fatigue. There was no difference in overall severity of depression, scores on the Global Assessment of Functioning, history of psychiatric hospitalizations, suicide attempts, time unemployed due to psychiatric reasons during the 5 years before the evaluation, and ratings of current and adolescent social functioning. There was no difference on any of the 5 subscales of the childhood trauma questionnaire. Overall, we found few differences between BPD patients with and without a family history of bipolar disorder thereby suggesting that a positive family history of bipolar disorder was not a useful marker for occult bipolar disorder in these patients.