Name: 5 Weird Things Your Blood Can Tell You
Uploaded: 2020-03-30T03:32:32.000Z
Duration: 11 min 2 s
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It usually isn't possible to simply glance at a sick person

and instantly know exactly what disease they have.

In order to diagnose diseases and assess risks, doctors often rely on biomarkers,

a broad category that basically represents anything they can measure

And one of the easiest things to collect and measure is blood.

But blood is fairly exceptional, in that it doesn't only tell you about blood-related diseases.

It can reveal information about everything from your brain to your unborn fetus.

Here are five things your blood can tell you about your health that you might not expect.

Doctors are working on ways to predict if your baby will be born

up to two months prematurely based on patterns in your blood.

Premature birth is one of the leading causes of infant death worldwide.

Around 15 million babies are born before 37 weeks every year.

But one way to help this at-risk population is by knowing their gestational age:

exactly how long they've been developing in the womb.

While being born prematurely carries risks no matter what,

the chance of medical complications increases as gestational age decreases.

So if a baby is born prematurely, a solid idea of how developed it is

will help doctors prepare for those complications.

Technologies like ultrasound can help us find gestational age,

but they don't give us as much information as we'd like on how likely a baby is to be born early.

Recently, scientists have turned to things called cell-free RNA transcripts, or cfRNA for short.

These are bits of the fetus's genetic information that make their way into the parent's blood.

Different genes are expressed at different times during pregnancy,

so depending on the amount of cfRNA we find from different types of tissue,

we can get an idea of the fetus's gestational age and risk for premature birth.

One 2018 study attempted to determine the genetic patterns in more detail,

in order to develop a cfRNA-based blood test to estimate the risk of preterm birth.

like increased cfRNA from the placenta and liver as the fetus developed.

Then they used those patterns to make a model and estimate when the baby would be born.

While the resulting model was fairly accurate at measuring gestational age,

And it could only accurately predict the delivery date for full term births, not preemies.

A few different things can trigger a preterm birth,

and since we don't totally understand how they work yet,

the research group thinks those unknown factors might be why their estimate isn't super accurate.

This new blood test isn't quite ready for the clinic yet.

The first experiment only tested a small number

of white and African American people at risk of preterm birth.

In the future, larger and more diverse samples

may be able to help develop a truly usable blood test.

And if you hit your noggin just right, you might experience

memory loss, dizziness, or other mental alterations,

all of which are signs of a traumatic brain injury called a concussion.

But no two concussions are diagnosed the same, so doctors need some objective markers.

Recently, they've used a blood test in combination with imaging like CT scans

When someone presents with signs of a concussion, doctors first give them a blood test,

and they're looking for two biomarkers in particular, GFAP and UCH-L1.

They're great biomarkers for head injuries because the amount we can detect

increases with the severity of the injury, so how much there is tells us how bad it is.

Plus, GFAP is only expressed in the brain,

which makes it a very specific marker for head trauma.

But if someone hits their head and doesn't show concussion symptoms,

we'd still like to know how bad their injury is.

Repeated smaller head injuries can still carry long term health risks,

like for athletes who experience repeated minor head trauma.

So doctors need a way to track these milder injuries.

A study published in 2019 looked at GFAP and UCH-L1 in people with head injuries.

Participants were categorized as either having concussion symptoms,

head injury without symptoms, or body trauma only.

The researchers tracked these biomarkers at different times after the injuries

They found that both biomarkers were elevated after head trauma,

although the level of UCH-L1 in someone's blood was higher after even minor head injuries,

meaning it wasn't useful for showing how bad the injury was.

GFAP, on the other hand, scaled up more consistently with the severity of head trauma,

even when the person didn't show symptoms.

This means that while both are still good markers for diagnosing concussion,

GFAP was more informative when it came to showing how bad.

While many doctors' offices already test for these biomarkers,

the researchers say that a wider range of measurement devices,

like for ambulances, may be available very soon.

By now you probably know that heart disease is kind of a big deal.

Heart disease is still the biggest killer in the world,

and having narrowed or blocked coronary arteries, otherwise known as atherosclerosis,

is one of the many risk factors for that.

But as you can imagine, no single test predicts your risk for this disease perfectly.

For instance, we already have plenty of biomarkers for cardiovascular disease risk by itself.

But if you have narrowed arteries, some of those biomarkers all of a sudden aren't as accurate.

There are a few ways to measure how blocked those vessels are, though.

This includes stuff like echocardiograms and exercise.

In early 2019, research out of Duke University Medical Center

tried to develop a test that used both exercise tests and biomarkers.

Using a combination of tests would give them a better idea

of what happens chemically around ischemia, when the heart doesn't get enough oxygen.

Specifically, they wanted to see what happened to those biomarkers

over the course of an exercise test and pick out any interesting patterns.

The researchers were interested in about 60 chemicals related to the heart's energy usage.

In particular, a group of chemicals called acylcarnitines.

So they recruited participants who were already patients in the emergency department

with heart disease symptoms like chest, jaw or shoulder pain.

Researchers took blood samples before and after the exercise test

and did an echocardiogram to get a picture of how blocked their coronary arteries were.

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