Screening for bipolar disorder and finding borderline personality disorder

Area of Science:

• Psychiatry
• Clinical Psychology

Background:

• Bipolar disorder and borderline personality disorder share overlapping symptoms, complicating differential diagnosis.
• The Mood Disorder Questionnaire (MDQ) is a common screening tool for bipolar disorder.
• Previous research indicates a high false-positive rate for the MDQ in certain patient populations.

Purpose of the Study:

• To investigate if psychiatric outpatients screening positive on the MDQ are more likely to be diagnosed with borderline personality disorder than those who do not screen positive.

Main Methods:

• The study involved 534 psychiatric outpatients interviewed using the Structured Clinical Interview for DSM-IV and Structured Interview for DSM-IV Personality Disorders.
• Participants completed the MDQ; 480 patients with complete data were analyzed.
• Patients with a bipolar disorder diagnosis were excluded from initial analyses.

Main Results:

• Borderline personality disorder was diagnosed in 21.5% of MDQ-positive patients versus 4.1% of MDQ-negative patients (P < .001).
• This association remained significant when restricted to patients with major depressive disorder (27.6% vs 6.9%, P = .001).
• Among all patients who screened positive on the MDQ, borderline personality disorder was diagnosed in 27.6% and bipolar disorder in 23.5%.

Conclusions:

• A positive MDQ result is equally likely to indicate borderline personality disorder as bipolar disorder.
• The clinical utility of the MDQ for bipolar disorder screening in routine practice is questionable.