Borderline Personality Disorder Is Not a Subtype of Bipolar Disorder

Broadening the concept of bipolar spectrum, selective attention to similarities between the spectrum and other disorders and ignoring the differences, abandonment of skillful clinical judgment and permissiveness in diagnosing this spectrum have led to the inclusion of several disorders such as borderline personality disorder in this spectrum. Grouping together borderline personality disorder and bipolar disorder might have therapeutic consequences for patients and, may even deprive them from appropriate treatment therefore, clarifying the differences between the two is of significant importance. Biological aspects such as neuro-transmitter abnormalities, serum cortisole level, dexa-methasone suppression test and sleep abnormalities of borderline patients resemble MDD more than they resemble bipolar disorders. From a phenomenological perspective, mood abnormalities of borderline patients are different from that of mood disorders in essence. Also, there are significant differences between the two disorders in terms of course and treatment. Therefore, if we pay attention to these disorders from different perspectives, we will find significant differences, which preclude the simple inclusion of borderline personality disorder within the bipolar spectrum.