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Is bipolar disorder
among children on the rise?
(November
2007 Issue)
By Ami Albernaz
Recent years have seen a striking rise in the number of bipolar
disorder diagnoses among children and adolescents, leading psychologists
and psychiatrists to wonder if bipolar disorder is truly on the
rise within these age groups, if the disorder was underdiagnosed
in the past and what other factors may be at play.
In the September issue of The Archives of General Psychiatry, a
team of researchers led by Mark Olfson, M.D., MPH, professor of
clinical psychiatry in the Center for Community Health Partnerships
at Columbia University Medical Center, reported a 40-fold increase
in bipolar diagnoses among young people between 1994 and 2003. The
study, one of several recently published on the topic, found that
the rate of bipolar diagnoses among adults doubled over the period.
Beginning in the 1990s, psychiatrists began looking more carefully
for signs of bipolar disorder in childhood. Though the condition
was diagnosed almost exclusively in adults until then, some believed
that early detection would lessen the debilitating effects of the
illness later on. Meanwhile, the DSM-IV, published in 1994, broadened
the diagnostic criteria to include the less severe bipolar II disorder,
likely contributing to the increase in the number of diagnoses,
Olfson acknowledges. Still, he says overdiagnosis also likely plays
a role.
"The magnitude and rapidity of the increase in treatment of youth
bipolar disorder, the predominance of boys in this study treated
for bipolar disorder, their young age and the substantial co-treatment
for ADHD all suggest overdiagnosis," Olfson wrote in an e-mail.
"At the same time, a substantial increase in academic attention
to bipolar disorder in young people may have also helped psychiatrists
and other mental health professionals to correct historical under-recognition."
David Fassler, M.D., a clinical professor of psychiatry at the
University of Vermont who has studied and written about bipolar
disorder among children and teenagers, says that up to half of young
people currently being treated for the disorder may be misdiagnosed.
"There's considerable overlap with other conditions, including
ADHD, conduct disorder, anxiety disorders and depression," Fassler
says. "Accurate diagnosis and effective treatment requires a careful
and detailed assessment, which can't realistically occur in a brief
office visit."
One possible contributor to the spike in diagnoses, Olfson says,
is that the DSM gives equal weight to elevated mood or euphoria
and irritability in identifying mania. Yet, as he points out, "these
are fundamentally different states. Whereas euphoria is highly specific
to bipolar, irritability may occur across a broad range of disorders
in children such as ADHD and oppositional defiant disorder and in
adults with generalized anxiety disorder, major depressive disorder
and other disorders."
For these reasons - and since irritability can, of course, strike
children and teenagers without disorders - Olfson believes "euphoria
should carry greater diagnostic specificity or weight for mania
than irritability."
The blurriness of the lines separating psychiatric disorders, particularly
among children, has led some to question whether a new framework
for understanding mental disorders is needed. "Our knowledge is
increasing, so perhaps there are many cases [of bipolar disorder]
we missed in the past," says Susy Sanders, Ph.D., a psychologist
in private practice in Phillips, Maine. "But we're just in the beginnings
of understanding the brain. Brain chemistry disorders don't fall
neatly into categories."
The fact that many disorders are comorbid and that two people with
the same diagnosis might respond in entirely different ways to the
same drug hints at the uniqueness of brain chemistry, Sanders suggests.
For instance, one child with classic attention deficit symptoms
combined with mania might respond to a psycho stimulant, while another
might respond to a mood stabilizer. "You may have very different
pictures of the same disorder," she says.
Most of the youth diagnosed with bipolar disorder in Olfson and
his colleagues' study were treated with psychotropic medications.
These include mood stabilizers, antidepressants and anti-psychotic
drugs, some of which have been shown to result in rapid weight gain
and sluggishness.
Fassler says that although drugs for bipolar disorder are more
readily available than they were in the past, they have been more
thoroughly tested in adults. "When it comes to kids, most of the
data on safety and efficacy is based on relatively short-term clinical
trials," he says. "We clearly need more large-scale, long-term studies
on the evaluation and treatment of bipolar disorder in children
and adolescents. Hopefully, the current findings will serve as an
added stimulus for such research."
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