Bipolar Disorder Overdiagnosed?

Many people who have been told by their doctors
that they have bipolar disorder don't really have it.

So say researchers who used a standardized, comprehensive, psychiatric
diagnostic interview to evaluate 700 adult psychiatric outpatients.

About 20% had previously been diagnosed with bipolar disorder. But only 13%
met the criteria, says Mark Zimmerman, MD, associate professor of psychiatry
and human behavior at the Warren Alpert Medical School of Brown University in
Providence.

"In about half of patients previously diagnosed with bipolar disorder,
we couldn't confirm the diagnosis," he tells WebMD.

There are real dangers to overdiagnosis, chief among them unnecessary
exposure to mood stabilizers and all their powerful side effects, Zimmerman
says. There's also the stigmatization of having a serious, possibly lifelong
mental illness .

The study is being published online by the Journal of Clinical
Psychiatry and presented at the annual meeting of the American Psychiatric
Association.

Why Is Bipolar Disorder Overdiagnosed?

Bipolar disorder used to be called manic depression because it is characterized by bouts of
depression and bouts of mania. Patients experience dramatic mood swings between
euphoria and severe depression; they may have hallucinations or delusions.

Patients with
anxiety , agitation, irritability, and restlessness that does not persist
are sometimes misdiagnosed with bipolar disorder, Zimmerman says.

"These could be symptoms of bipolar disorder. But they really have to be
accompanied by other criteria, such as hyperactivity, feeling energetic despite
just a few hours of
sleep , or inflated self-esteem," he says.

Ironically, one reason the disorder is being overdiagnosed is "because
so much has been written about it being under-recognized," Zimmerman
says.

"It's difficult to go to a lecture on bipolar disorder that doesn't
begin with, 'Make sure you don't miss...,'" he says. "So clinicians are
loathe to miss it."

The increased availability of medications for the
treatment of bipolar disorder may also play a role in overdiagnosis, Zimmerman
says. "Physicians have a tendency to diagnose something that they feel they
comfortable treating," he says.

So what should you do if you think you've been misdiagnosed with bipolar
disorder?

"If you're at all uncertain about the diagnosis, speak to your doctor
and make sure you understand why you've been given that diagnosis. If you
remain unconvinced, get a second opinion," Zimmerman says.

What you shouldn't do, he stresses, is just stop taking your medication.

Children Misdiagnosed, Too

For the study, psychiatric outpatients completed a questionnaire that asked
whether they had ever been diagnosed with bipolar or manic-depressive disorder
by a health care professional.

Then, without knowing the responses, the researchers used a tool called the
Structured Clinical Interview for DSM-IV (SCID) to determine if the patients
met the criteria for bipolar disorder.

"The standardized nature of the SCID interview forces the clinician not
to miss things that could be missed in an unstructured interview,"
Zimmerman says.

National Institute of Mental Health Director Thomas Insel, MD, says
misdiagnosis of bipolar disorder is a problem in children as well as
adults.

"In children, it can be even more difficult to recognize and diagnose
because it does not fit precisely the symptom criteria established for
adults," he tells WebMD.

By Charlene Laino
Reviewed by Louise Chang
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