Reimagining Mental Health Diagnosis
let me start with a statistic
if you think about all the people that
you know one out of every four has
serious mental illness and among those
that do
given that many of you are young people
it’s important to know
that three out of every four
that develop mental illnesses have their
onset before age 25.
so given that these illnesses begin
early and often last
many years it’s important to get the
diagnosis right
so the main point i am going to make
here is that the way
mental health diagnoses are made has a
problem
and this problem can be addressed by
rethinking or
reimagining our approach to mental
health diagnosis
and making a diagnosis that is valid
actually improves lives maybe even saves
lives
let me illustrate this point by first
thinking about how
doctors generally think in medicine
many years ago i had just come back from
abroad
and i had been experiencing some
symptoms of
chest discomfort and stomach discomfort
nausea no appetite
being a doctor myself i kind of thought
it is just an
indigestion it will go away and they
didn’t do anything for a couple of days
the symptoms got
really worse i ended up in the emergency
room and the doctors when they
see a middle aged man walking in with a
chest discomfort the first thing to
think about is whether i was having a
heart attack
and they took me to the cath lab and did
an ecg an electrocardiogram of the heart
electrical wave recording which turned
out to be
normal so then they put that spotlight
on
my the rest of my body and found that i
was actually growing
bacteria in my blood and my liver
enzymes were up
so i might have some kind of a
gastrointestinal problem they
started me on antibiotics and i got
better and i’m here to
talk to you about this today
now in psychiatry doctors do it a bit
differently
so i’ll illustrate that point by a young
woman that i took care of many years ago
sort of early in my career
let’s call her mary i asked mary
she had come to me after being seen by
many other psychiatrists
she had not accepted treatment and asked
her
why are you here mary what brings you to
my clinic
she said i have been having some
attention problems can’t concentrate in
my school
all through my childhood and in middle
school i began having anxiety and panic
attacks
in high school i started having some
depression in college i began having
some mood swings and over the last
couple of years
i have been having some thinking
difficulties some paranoia confusion
some memory problems so i asked her mary
what did the doctors tell you your
diagnosis says
she said initially they called i have
adhd and then they said i have an
anxiety disorder then they said i have a
major depressive disorder
and more recently that they said i have
a bipolar disorder and
last year they said i might have
schizophrenia
so she then asked the question what do
you think
can you come up with a diagnosis that i
don’t already know
all doctors have basically been
restating my symptoms
in technical terms and calling it a
diagnosis
so can you prove that i have
schizophrenia by a
brain scan or a blood test can you give
me a diagnosis that helps me
understand the nature of my brain
problem
can you tell me give me a diagnosis that
tells me
that i am on the right treatment these
are
sobering questions that many other
patients have asked me throughout
my career mary is not the only one in
fact the whole field of psychiatry is
under criticism because we don’t have a
very good answer for these kind of
questions
why do we make a diagnosis in the first
place what you see here
is the bible of psychiatry which we call
the dsm
or diagnostic statistical manual of
mental disorders
this is a good document everybody uses
it around the world
because the dsm gives us criteria
to make diagnosis of almost every mental
disorder
these criteria give us a kind of a
useful shorthand
so that we can communicate accurately
between doctors about
describing the same individual with
symptoms of the same kind
in the same diagnostic terms which is
important
both for communication between doctors
as well as for communication with
insurance companies and legal people and
so forth
but what the diagnostic terms in dsm
does not tell us is what the underlying
illness is
so while it has it is reliable and
consistent
these categories may not be valid they
may not be telling as much about the
underneath underlying disease
so let me explain to you the two
two terms reliability and validity in
this cartoon
on the left what you see is this man
shooting an arrow consistently to the
same point on the target board
but missing the bull’s eye so it’s
highly reliable
but not valid but on the other hand on
the right side what you see
are all the arrows are hitting the same
spot
reliable and also they are hitting the
bulls high so they’re valid
so the important point is that in
psychiatry we need diagnoses that are
both reliable
and valid
how do we move towards more
validity in psychiatric diagnosis
after all all mental disorders one way
or the other
have a relationship to something or the
other in
going wrong in the brain all major
mental disorders
the organ of the speciality of
psychiatry is the brain
just like it is the heart for the
ecology cardiologists
and the kidney for the nephrologists but
psychiatrists are somehow
shy to look at the organ of their system
namely the brain when they make their
diagnosis
when you have a trouble with your car
and you take it to a mechanic the
mechanic looks under the hood
and looks at whether the engine is the
problem or it is the cooling system and
so on this
psychiatrist could do the same thing in
the last several years
there have been exciting new discoveries
of different kinds of brain scans
which i have shown here in this slide
the cartoon that
i drew myself and the bottom right is
the
mri scan which gives you exquisite
pictures of the structure
function and maybe chemistry of the
brain
and in the middle what you see is the
electroencephalogram
which is the way just like the ecg of
the head
using electrodes in a completely safe
manner
you can get electrical recordings of the
brain’s activity
and thereby look at the functioning of
the brain
now how can we apply these kind of tests
or
biomarkers as we call them in
psychiatric disorders let’s go back to
the same kind of symptoms that i
presented with
if someone like me walked into the
emergency room
with a stomach upset and nausea and
appetite
and they simply said you have an
indigestion take these pills and go home
i would probably be dead by now but
rather than that
the doctors did an ecg ruled out heart
disease
and then looked elsewhere in my body
and examined my blood and the
gastrointestinal system and came up with
a diagnosis of a
gastrointestinal infection that was
causing
a bacteremia an increase in bacteria in
the blood
that’s the way medicine should proceed
but
let’s see how we might apply this to
psychiatry
so beginning many years ago a number of
researchers including our own group in
boston have been looking at
a large number of people with severe
mental illness psychotic disorders
and asking the question whether the
different dsm categories like
schizophrenia and schizoaffective
disorders
might differ in their biomarkers so we
examined this population on whom we had
electrophysiological data like eeg
and cognitive test data and we first
asked the question
whether the three diagnostic groupings
namely schizophrenia schizophrenia
and bipolar disorders showed any
differences in terms of their biology
but the answer was a resounding no
all of these disorders looked pretty
much similar in terms of their brain
abnormalities so we scratched our heads
and took a different approach
why not just ignore the symptoms and
apply machine learning
to these biomarker data across
nearly 2 000 people and whether we can
come up with
different kinds of categories that may
make more sense
and indeed we came up with three
biological categories based on sets of
biomarkers which we call them biotypes
which had no resemblance to the dsm
categories that we
had been all along using
why is that important you might remember
i said
our patient mary had asked the question
can you
take a brain picture and tell me that i
have
a particular disease with a particular
brain abnormality
and you can you prove that i have
schizophrenia using
brain scans and when you look at
our own scans in these data sets whether
it is schizophrenia or bipolar disorder
or schizoaffective disorder they don’t
seem to look different
and a particular brain structure called
the hippocampus
a tiny structure which we can now
examine in exquisite detail by modern
neuroimaging techniques
the hippocampus which is important for
memory thinking and belief formation
did not differ between the symptom
categories of schizophrenia
schizophrenia or bipolar disorders
but if you look at them the same
structure
across the three biotypes the
differences were like day and night
biotype 1 is characterized by a
prominent hippocampal abnormality which
might explain
her illness better than anybody else’s
illness so there might be different
subtypes which are different
biologically now our patient might ask
the question how does it make a
difference
for my treatment now when we do
categorize
illnesses based on their biology
we also understand what the
physiological
signatures or fiddle the physiological
alterations that lie underneath these
we have discovered that biotype 1 is
characterized
by a diminished response of
nerve cells or neurons to sensory
stimulation
you can call it an underactive brain
by contrast biotype 2
is characterized by an inefficient
overactivity of
these neurons in response to sensory
stimuli
biotype 3 we did not find much
differences from healthy people
so it’s quite possible that the biotype
1 patients
might respond to treatments that enhance
brain activity like brain exercises
cognitive training
also some medicines like clozapine which
may increase increased brain
electrophysiological activity
in contrast biotype 2 which is
characterized by
over reactive inefficient brain
what you need are treatments that calm
these nerves
it may be certain medicines like
welprovate
or it may be certain newer treatments
what we call
neuromodulation an example of that is
transcranial magnetic stimulation which
can suppress
inefficient overactivity biotype 3
which does not seem to show much brain
changes
but still they have symptoms it’s quite
possible
that they may respond to smaller doses
of medications
maybe they need psychotherapy much more
and a good follow-up
i’m going to end with this point that
making a valid
diagnosis has value a valid diagnosis
has value first of all it will tell you
more about the underlying illness
and second of all knowing what the
underlying illness
is would help the doctors to discover
better treatments
and also to match the existing
treatments
in the correct way to the correct
patient in other words
personalize the treatments to the
individual patients
situation and finally
mental health disorders are highly
stigmatized it’s a major barrier in
their recovery stigma is because
quite often they either blame themselves
or the society
for these illnesses but if only we knew
and if our patients
know that there are certain brain
circuitry alterations
that can explain their illness it is
likely
very likely to reduce stigma and improve
their
engagement in treatment thank you