If Bipolar Disorder Is Over-diagnosed, What Are The Actual Diagnoses?

http://www.sciencedaily.com/releases/2009/07/090729100936.htm

ScienceDaily (July 29, 2009) — A year ago, a study by Rhode Island Hospital and Brown University researchers reported that fewer than half the patients previously diagnosed with bipolar disorder received an actual diagnosis of bipolar disorder after using a comprehensive, psychiatric diagnostic interview tool --the Structured Clinical Interview for DSM-IV (SCID). In this follow-up study, the researchers have determined the actual diagnoses of those patients.
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Under the direction of lead author Mark Zimmerman, MD, director of outpatient psychiatry at Rhode Island Hospital, the researchers' findings indicate that patients who received a previous diagnosis of bipolar disorder that was not confirmed by a SCID, they were significantly more likely to be diagnosed with borderline personality disorder as well as impulse control disorders.
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The results of the study also indicate that patients who had been over-diagnosed with bipolar disorder were more frequently diagnosed with major depressive disorder, antisocial personality disorder, posttraumatic stress disorder and eating and impulse disorders.

Zimmerman and colleagues note that "we hypothesize that in patients with mood instability, physicians are inclined to diagnose a potentially medication-responsive disorder such as bipolar disorder rather than a disorder such as borderline personality disorder that is less medication-responsive."

I expect that doctors feel better when they diagnose something they can help more easily and quickly. Also, health insurance is more likely to pay for medication than for psychotherapy.

In their previously published study that concluded bipolar disorder was over-diagnosed, they studied 700 patients. Of the 700 patients, 145 reported they had been previously diagnosed as having bipolar disorder; however, fewer than half of the 145 patients (43.4 percent) were diagnosed with bipolar disorder based on the SCID. The authors state that the over-diagnosis of bipolar disorder can have serious consequences, because while bipolar disorder is treated with mood stabilizers, no medications have been approved for the treatment of borderline personality disorder. As a result, over-diagnosing bipolar disorder can unnecessarily expose patients to serious medication side effects, including possible impact to renal, endocrine, hepatic, immunologic and metabolic functions.

Zimmerman concludes, "Because evidence continues to emerge establishing the efficacy of certain forms of psychotherapy for borderline personality disorder, over-diagnosing bipolar disorder in patients with borderline personality disorder can result in the failure to recommend the most appropriate forms of treatment."