What your breath could reveal about your health Julian Burschka
Translator: Joseph Geni
Reviewer: Camille Martínez
I have a tendency to assume the worst,
and once in a while,
this habit plays tricks on me.
For example, if I feel
unexpected pain in my body
that I have not experienced before
and that I cannot attribute,
then all of a sudden, my mind
might turn a tense back into heart disease
or calf muscle pain
into deep vein thrombosis.
But so far, I haven’t been diagnosed
with any deadly or incurable disease.
Sometimes things just hurt
for no clear reason.
But not everyone is as lucky as me.
Every year, more than
50 million people die worldwide.
Especially in high-income
economies like ours,
a large fraction of deaths is caused
by slowly progressing diseases:
heart disease, chronic lung disease,
cancer, Alzheimer’s, diabetes,
just to name a few.
Now, humanity has made tremendous progress
in diagnosing and treating many of these.
But we are at a stage
where further advancement in health
cannot be achieved only
by developing new treatments.
And this becomes evident
when we look at one aspect
that many of these
diseases have in common:
the probability for successful treatment
strongly depends on
when treatment is started.
But a disease is typically only detected
once symptoms occur.
The problem here is that, in fact,
many diseases can remain asymptomatic,
hence undetected,
for a long period of time.
Because of this, there is
a persisting need for new ways
of detecting disease at early stage,
way before any symptoms occur.
In health care, this is called screening.
And as defined by
the World Health Organization,
screening is “the presumptive
identification of unrecognized disease
in an apparently healthy person,
by means of tests … that can be applied
rapidly and easily …”
That’s a long definition,
so let me repeat it:
identification of unrecognized disease
in an apparently healthy person
by means of tests that can be applied
both rapidly and easily.
And I want to put special emphasis
on the words “rapidly” and “easily”
because many of the existing
screening methods
are exactly the opposite.
And those of you
who have undergone colonoscopy
as part of a screening program
for colorectal cancer
will know what I mean.
Obviously, there’s a variety
of medical tools available
to perform screening tests.
This ranges from imaging techniques
such as radiography
or magnetic resonance imaging
to the analysis of blood or tissue.
We have all had such tests.
But there’s one medium
that for long has been overlooked:
a medium that is easily accessible,
basically nondepletable,
and it holds tremendous promise
for medical analysis.
And that is our breath.
Human breath is essentially
composed of five components:
nitrogen, oxygen, carbon dioxide,
water and argon.
But besides these five, there are
hundreds of other components
that are present in very low quantity.
These are called volatile
organic compounds,
and we release hundreds,
even thousands of them
every time we exhale.
The analysis of these volatile
organic compounds in our breath
is called breath analysis.
In fact, I believe that many of you
have already experienced breath analysis.
Imagine: you’re driving home
late at night,
when suddenly, there’s
a friendly police officer
who asks you kindly but firmly
to pull over and blow
into a device like this one.
This is an alcohol breath tester
that is used to measure
the ethanol concentration in your breath
and determine whether driving
in your condition is a clever idea.
Now, I’d say my driving was pretty good,
but let me check.
(Beep)
0.0, so nothing
to worry about, all fine.
(Laughter)
Now imagine a device like this one,
that does not only measure
alcohol levels in your breath,
but that detects diseases
like the ones I’ve shown you
and potentially many more.
The concept of correlating
the smell of a person’s breath
with certain medical conditions,
in fact, dates back to Ancient Greece.
But only recently, research efforts
on breath analysis have skyrocketed,
and what once was a dream
is now becoming reality.
And let me pull up this list again
that I showed you earlier.
For the majority of diseases listed here,
there’s substantial scientific evidence
suggesting that the disease
could be detected by breath analysis.
But how does it work, exactly?
The essential part is a sensor device
that detects the volatile
organic compounds in our breath.
Simply put: when exposed
to a breath sample,
the sensor outputs a complex signature
that results from the mixture of volatile
organic compounds that we exhale.
Now, this signature represents
a fingerprint of your metabolism,
your microbiome
and the biochemical processes
that occur in your body.
If you have a disease,
your organism will change,
and so will the composition
of your exhaled breath.
And then the only thing that is left to do
is to correlate a certain signature
with the presence or absence
of certain medical conditions.
The technology promises
several undeniable benefits.
Firstly, the sensor can be miniaturized
and integrated into small,
handheld devices
like this alcohol breath tester.
This would allow the test to be used
in many different settings
and even at home,
so that a visit at the doctor’s office
is not needed each time
a test shall be performed.
Secondly, breath analysis is noninvasive
and can be as simple as blowing
into an alcohol breath tester.
Such simplicity and ease of use
would reduce patient burden
and provide an incentive
for broad adoption of the technology.
And thirdly, the technology is so flexible
that the same device could be used
to detect a broad range
of medical conditions.
Breath analysis could be used to screen
for multiple diseases at the same time.
Nowadays, each disease typically requires
a different medical tool
to perform a screening test.
But this means you can only find
what you’re looking for.
With all of these features,
breath analysis is predestined
to deliver what many traditional
screening tests are lacking.
And most importantly,
all of these features should
eventually provide us
with a platform for medical analysis
that can operate at attractively
low cost per test.
On the contrary, existing medical tools
often lead to rather high cost per test.
Then, in order to keep costs down,
the number of tests
needs to be restricted,
and this means (a) that the tests
can only be performed
on a narrow part of the population,
for example, the high-risk population;
and (b) that the number of tests
per person needs to be kept at a minimum.
But wouldn’t it actually be beneficial
if the test was performed
on a larger group of people,
and more often and over a longer period
of time for each individual?
Especially the latter would give access
to something very valuable
that is called longitudinal data.
Longitudinal data is a data set
that tracks the same patient
over the course of many months or years.
Nowadays, medical decisions
are often based on a limited data set,
where only a glimpse
of a patient’s medical history
is available for decision-making.
In such a case,
abnormalities are typically detected
by comparing a patient’s health profile
to the average health profile
of a reference population.
Longitudinal data would
open up a new dimension
and allow abnormalities to be detected
based on a patient’s own medical history.
This will pave the way
for personalized treatment.
Sounds pretty great, right?
Now you will certainly have a question
that is something like,
“If the technology is as great as he says,
then why aren’t we using it today?”
And the only answer I can give you is:
not everything is as easy as it sounds.
There are technical
challenges, for example.
There’s the need for
extremely reliable sensors
that can detect mixtures
of volatile organic compounds
with sufficient reproducibility.
And another technical challenge is this:
How do you sample a person’s breath
in a very defined manner
so that the sampling process itself
does not alter the result of the analysis?
And there’s the need for data.
Breath analysis needs
to be validated in clinical trials,
and enough data needs to be collected
so that individual conditions
can be measured against baselines.
Breath analysis can only succeed
if a large enough data set
can be generated
and made available for broad use.
If breath analysis
holds up to its promises,
this is a technology
that could truly aid us
to transform our health care system –
transform it from a reactive system
where treatment is triggered
by symptoms of disease
to a proactive system,
where disease detection,
diagnosis and treatment
can happen at early stage,
way before any symptoms occur.
Now this brings me to my last point,
and it’s a fundamental one.
What exactly is a disease?
Imagine that breath analysis
can be commercialized as I describe it,
and early detection becomes routine.
A problem that remains
is, in fact, a problem
that any screening activity has to face
because, for many diseases,
it is often impossible to predict
with sufficient certainty
whether the disease
would ever cause any symptoms
or put a person’s life at risk.
This is called overdiagnosis,
and it leads to a dilemma.
If a disease is identified,
you could decide not to treat it
because there’s a certain probability
that you would never suffer from it.
But how much would you suffer
just from knowing that you have
a potentially deadly disease?
And wouldn’t you actually regret
that the disease was detected
in the first place?
Your second option
is to undergo early treatment
with the hope for curing it.
But often, this would not come
without side effects.
To be precise:
the bigger problem is not overdiagnosis,
it’s overtreatment,
because not every disease
has to be treated immediately
just because a treatment is available.
The increasing adoption
of routine screening
will raise the question:
What do we call a disease
that can rationalize treatment,
and what is just an abnormality
that should not be a source of concern?
My hopes are that routine screening
using breath analysis
can provide enough data and insight
so that at some point,
we’ll be able to break this dilemma
and predict with sufficient certainty
whether and when to treat at early stage.
Our breath and the mixture of volatile
organic compounds that we exhale
hold tremendous amounts of information
on our physiological condition.
With what we know today,
we have only scratched the surface.
As we collect more and more data
and breath profiles across the population,
including all varieties of gender,
age, origin and lifestyle,
the power of breath analysis
should increase.
And eventually, breath analysis
should provide us with a powerful tool
not only to proactively detect
specific diseases
but to predict
and ultimately prevent them.
And this should be enough motivation
to embrace the opportunities
and challenges
that breath analysis can provide,
even for people that are not
part-time hypochondriacs like me.
Thank you.
(Applause)