This is the second of a
three-part series to inform you about research on juvenile bipolar disorder
sponsored by the Juvenile Bipolar Research Foundation. If you missed either of the first two
Newsletters, you can click here to refer to
them http://www.bipolarchild.com/Newsletters/ We hope you will be encouraged by the progress and
inspired to believe that the end of this journey is attainable.
What do the following have
in common?
- deflects blame
- suffers horrendous nightmares
- antagonizes siblings
- excessively craves sweets and carbohydrates
- functions in mission mode
- wets the bed
- sleeps hot
- takes excessive risks
- hoards food
- has many ideas at once
- interrupts or intrudes on others
- experiences periods of self-doubt and poor
self-esteem
Independently, each of
these traits is a symptom of a myriad of different psychiatric disorders. Considered together, they are all
symptoms of Pediatric Bipolar Disorder (PBD).
But wait a minute! Isn't
bipolar disorder all about mania and depression? How can these unrelated symptoms be part of that same
profile?
This more complete list of
symptoms is reflective of the research progress JBRF has made by adopting the dimensional
approach of defining psychiatric disorders: symptoms overlap between
psychiatric conditions and one condition is differentiated from the other by
how those clusters of overlapping symptoms come together.
Proceeding down this path,
researchers have arrived at a novel perspective of the illness. While traits like mania and depression
remain important, this analysis finds that they are not the central behavioral
dimensions of PBD. Other
dimensions such as aggression, anxiety, sensory sensitivity, sleep/wake
disturbance, attention/executive function deficit, and oppositional behavior
also figure prominently. Of
paramount interest is a dimension that establishes a link between obsessive
fears and aggressive behavior. JBRF investigators have termed this correlation "Fear-of-Harm"
(FOH). This new characterization
of PBD has been labeled the "Core phenotype".
The Core phenotype
is a more complete and accurate description of what these children experience
than what is offered by the Diagnostic and Statistical Manual for Mental
Disorders (DSM). Investigators
suggest that in the DSM, bits and pieces of this single disorder have been
parceled out into numerous other diagnoses. It is likely that this fragmented perspective of the
disorder has obscured a clear view of its actual presentation in children and stalled
efforts to get at the underlying biology.
Concentrated exploration
of the FOH trait has lead investigators to define a clinically
homogeneous subgroup of children who are the most severely impacted by this
disorder. This subgroup is called
the FOH phenotype. These
children are characterized by extreme anxiety and the hyper-perception of
threat which causes them to respond in a defensively retaliatory manner. They are often hospitalized and face
great challenges socially and academically.
Not only have research investigators been
able to describe the symptom profile of this FOHphenotype, but under this new paradigm, they have also pieced
together the likely underlying biology involved in the disorder. Certain brain areas, activities and
development that had not previously been considered became obvious foci for
their attention. The specific
neural pathway that ties these activities together in a manner consistent with
the profile has been identified.
Investigation of this complex system is ongoing. The more the details fall into place,
the greater its explanatory value grows.
The FOH phenotype moves us
further in our quest to uncover the genetic variations associated with
PBD. The high heritability of the
FOH trait, refinement of the dimensionally derived symptoms that associate with
it, and the fact that the CBQ can identify with 96% accuracy
children whose profiles fit the phenotype make us optimistic that we are on the
right path for a meaningful genetic analysis.
JBRF actively supports the
collection DNA from children whose CBQ scores indicate that they fit the FOH
Phenotype.
This novel understanding
of the dimensions of bipolar disorder in childhood puts us on much firmer
footing as we move towards the identification of biological markers. The identification of new biological
markers opens the door for new treatments.
We are hopeful that this
compelling work will facilitate the much needed consensus amongst researchers
that will unite their creative minds into a common direction and thus enable us
to move ahead more quickly on this journey towards relief.
Alissa Bronsteen and Demitri Papolos, M.D.
