
I'm a Heart Doctor and Wary of the New Apple Watch - elorant
https://medium.com/s/story/im-a-heart-doctor-heres-why-im-wary-of-the-new-apple-watch-2b1999f2d942?mbid=social_fb
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dan000892
“Since all medical interventions come with risks, many people will suffer harm
from unnecessary tests and procedures.”

I agree with this statement generally, but in this specific case it seems
tenuous. If the iWatch’s 1-lead EKG detected a-fib, the next course of action
would be a more reliable diagnostic, specifically a proper 12-lead EKG
interpreted by a qualified medical professional, perhaps followed by a Holter
monitor to record 5 or more leads over a 48+ hour period.

A 12-lead involves attaching ten electrode stickers to a patient which are
then wired up to a backpack-sized monitor which passively reads the difference
in electrical activity between specific electrodes. It’s a simple non-invasive
procedure that’s performed a hundred thousand times a day in the US. In fact,
it’s so simple and low-risk that I as a lowly EMT am allowed to perform it.
(To drive this point home, the state of California does not allow me to prick
a patient’s finger to get the drop of blood required to ascertain blood sugar.
I need a paramedic to do that for me.)

It’s absurd for this doctor to suggest an asymptomatic young person could be
prescribed anticoagulants for a-fib “diagnosed” by an iWatch. I can understand
doctors expressing opposition to “self-diagnostic medicine” but to make these
arguments about a 1-lead makes as much sense as arguing that people shouldn’t
be able to buy and operate a blood pressure machine without a prescription.

~~~
ghufran_syed
Not so “absurd” - you may be missing some context.

A 12-lead ecg can diagnose whether you have a-fib _at the time of the ecg_.
The question for the doctor is whether you may have “paroxysmal” ie
intermittent a-fib. So what if the Apple Watch said ‘a-fib’, but the 12-lead
is negative. Most doctors are probably going to end up ordering a holter-
monitor, to monitor the patient’s rhythm over 24-72 hours. Some proportion of
those patients may have very short runs of a-fib, and would likely have
remained blissfully ignorant (and well) without the Apple Watch. Instead, they
may well end up anti-coagulated, because if that patient is not anticoagulated
and gets a stroke later ( which may or may not be due to a-fib), the doctor is
going to get sued. Whereas if the doc starts the patient on anticoagulants,
and tells the patient that, “ there’s a risk of bleeding, but...”, that is
much less likely to end up in a lawsuit.

~~~
toxik
Wait, so the argument against having more data is that sometimes that data is
misinterpreted or misunderstood? That does not seem like a good argument.

~~~
Barrin92
it's a very reasonable argument if the outcomes of this are overtreatment or
serious health scares and increased cost with little payoff as a result.

More data is useless if your data is mostly noise and if as a result error
rate in treatment and costs rise. Add to this the strong incentive for
doctors, especially in a profit-driven healthcare system to suggest action,
this could easily lead to the rise of unnecessary treatment of benign
abnormalities in otherwise healthy people.

This is also not speculation. Ever since the rise of diagnostics in medicine
overtreatment has become more and more common. This study[1] estimates that
almost a fifth of all procedures in the US are not necessary.

[1][https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5587107/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5587107/)

~~~
toxik
Interesting standpoint, one which I disagree with.

You are making a causal connection of rise in diagnostic tools =>
overtreatment. What is your evidence for that, apart from overtreatment
increasing? I think sea levels have risen since then too, are they also an
effect of too much diagnostics?

Clearly, if the data was just noise, people would eventually stop caring. But
you'd have to be pretty cynical to think one of the major tech companies of
the world releases a diagnostic device that has an S:N ratio that high.

A more likely explanation for the overtreatment is simply that people are
getting richer, and society is providing more care -- to a fault. I know this
first hand, I have had invasive surgery done that I would've been better
without -- because the doctor thought it maybe might be a good thing for the
future. Spoiler: it worsened the problem.

I think if it were the case that we all suffer from a bit of a-fib every now
and then, and that these diagnostic tools will give false positives for this
reason, then that would be news to the medical community and thus progressing
our understanding. People would be told, "your watch is telling you this but
we know better now." Apple might update their detection algorithm. It's such a
small price to pay for the obvious advantage of preventing loss of life.

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dpatrick86
It really sounds like a software issue to me. If the watch is causing atrial
fibrillation to be detected too often, then you can either make the software
meet some greater threshold before alerting the user.. or, even better,
determine more fully formed diagnostic criteria to be applied.

The fact that medicine hasn't studied whether or not healthy hearts are
regularly doing this because sensors were inconvenient previously, doesn't
mean we need to get rid of the sensors. It means that both the presentation of
the software should have some sort of feedback loop from clinical research
that should emerge as a consequence of that data now... existing.

~~~
esalman
> _you can either make the software meet some greater threshold_

That will, on the other hand, increase false negatives. I think that will
defeat the whole purpose of putting the sensor in the watch.

> _medicine hasn 't studied whether or not healthy hearts are regularly doing
> this because sensors were inconvenient previously_

Medicine has studied this. It is just that this specific kind of diagnosis is
subjective and there are a lot of debate.

The main point, from what I understood, the author is arguing is that the one-
lead EEG of the Apple watch is prone to higher false positives, and users
should take it with a grain of salt.

~~~
Kliment
The way I read it, applying something with a nonnegligible false positive rate
to a much larger population (that is, screening everyone without indications)
will lead to many incorrect diagnoses because your error rate is multiplied by
a large healthy population. Whereas applying diagnostic tests only to people
with suspected a-fib gives you a smaller group with a higher base rate of what
you're looking for, so false positives are not as much of a problem.

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leot
Utter hogwash. The author's mistake, often made by physicians when presented
with technology that gives consumers more information, is that consumer
knowledge and attitudes remain static.

In fact, while this may at first lead to a bunch of hypochondriac-like
behaviors, people's fascination with themselves will quickly teach them to not
be alarmed.

~~~
chmaynard
I agree. I was immediately suspicious when the author identified himself as a
"heart doctor". The correct term is cardiologist, as everyone knows. He should
be communicating directly with the FDA, not blogging about his concerns to
raise alarms.

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dev_dull
> _I worry that the Apple Watch will discover lots of short-duration AF or AF
> occurring in younger people with fewer risk factors. Given their lower risk
> of stroke, it’s unlikely that anticoagulant drugs will deliver similar
> benefits. But anticoagulants do increase the risk of bleeding._

This is completely grounded in science. And we should be weary of going to the
doctor too often:

> _Medical Errors Are Third Leading Cause of Death in the U.S._

1\. [https://www.usnews.com/news/articles/2016-05-03/medical-
erro...](https://www.usnews.com/news/articles/2016-05-03/medical-errors-are-
third-leading-cause-of-death-in-the-us)

~~~
philwelch
The vast majority of these fatal medical errors happen in the hospital, and
healthy people don't often end up hospitalized. Much of the time, the
alternative to hospitalization is going to be fatal anyway.

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empath75
So I started having premature ventricular contractions a couple of years ago,
and had a lot of anxiety around it — I made multiple emergency room visits and
trips to the cardiologists because I was convinced that when they were giving
me ecgs, they weren’t getting it when I was having a severe problem and were
missing a-fib(which runs in my family)

They eventually told me to get a Kardia so I could check it whenever I wanted
to.

After a few weeks of checking every time I thought something was going on and
periodically sending the worst examples to their analysts, I realized it was
only ever pvcs, and it dramatically lowered my stress levels and made the
episodes much less severe and shorter lasting. It also helped me figure out my
triggers (caffeine) and helped me realize that going on a brisk walk for 15
minutes pretty much always stops them.

I wouldn’t say the Kardia saved my life or made me healthier, but it
absolutely helped me get a handle emotionally on what was going on with my
heart and improved my quality of life. I don’t carry it around any more, but I
definitely think it’s worth getting (or the new watch) if you have
palpitations and want to get a better idea of what’s going on.

~~~
gist
The issue is not whether it would be of benefit to someone like you. The issue
is if having that feature as well as the downside risk to people who are in
the general public and don't have a particular risk factor or need. Also it's
not an option it's built in the core product. As such it will alarm people
that have no reason to be using it in the first place even if it ends up
alerting and saving some people in the process.

Is it worth it to give 1000 people anxiety, tests, medication in order to
provide benefit to 10 people or even 100? (those numbers are made up to
illustrate and are fictitious).

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Latteland
This article needs more analysis. How many people who didn't know about af
will be detected by the device, compared to the 100k estimated false
positives. And do these pan out the same way for other heart ailments.

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swingline-747
In my experience, doctors have widely-varying, fact-free opinions that are
often wrong on wearables' personal quant and consumer medical devices'
precision & accuracy. Heck, some are even wrong on home-medical equipment. The
reasons are medical school drills into them two things 1) only doctors and
specialists can be "right" 2) everything else is wrong. This creates an
opinion based on narcissism and elitism, rather than data.

Take a FitBit Charge HR 2. The one I have is consistently within 2-5% of
hospital & doctor office pulse readings. That doesn't mean it's perfect in all
circumstances, but that it's observations haven't been discredited with
evidence and there's little/no counterexamples to show that a device I wear is
somehow "inaccurate."

Another doctor claimed home blood pressure cuffs, products strictly-regulated
by the FDA, are "widely inaccurate." This also seems binary-thinking FUD and
wrong, because, anecdotally, I checked repeatedly and have an accurate
consumer blood-pressure meter.

This is what happens when a profession encourages people to invest their egos
in a preordained outcome.

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wlesieutre
I don’t know about the ECG part, but buying an Apple Watch has definitely made
me exercise more

~~~
stri8ed
How so?

~~~
pen2l
Apple Watch 'gameifies' fitness. You set a goal of burning a certain amount of
calories, "moving" a certain distance, etc. -- and it tracks these things, and
gives you little "awards" for when you successfully meet your goals per week
or per month, and tries to encourage you in smart ways if you're not making
your goals ("Hey if you do a brisk walk in the next few minutes, you'll have
met your goal!!"). I find that these reminders work pretty well for me.

As well, if you have peers who have Apple Watch/fitbit, there are tons of apps
you can use to "compete" with them.

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zaphirplane
Not a fan of the dumb it down title of heart doctor, cardiologist I feel is
fairly widely known, and dumbing it down makes me think that they are dumbing
or glossing over other points

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guzik
I must agree with the potential harm of increased false positives but I am not
sure if this is the real issue here. In a short period of time, it is
impossible to accurately analyze heart trends to find AFib. I mean, people
might feel that everything is okay when it's not (false negatives ARE
problematic), which can be only determined in full 24h+ / 12-lead ECG scan.
However, 20-30s ECG monitoring is still adequate to gather information about
some of the disabilities of the user's heart (for example, if any ventricle is
damaged).

When we were bootstrapping with a similar idea as Apple Watch at Aidlab, all
cardiologist were looking at us like we were crazy. Well, seems we were
talking with wrong doctors, and we should go straight to Dr. Ivor Benjamin.

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threatofrain
So the argument of the article is that widespread screening may cause net
harm. The issue is with the imprecision of the test, as well as the followup
procedures necessary to be precise, and the probability of mistreatment.

~~~
DanBC
No. We know that widespread screening does cause harm, even if the tests are
100% accurate.

~~~
fearoffish
Could you show me the evidence for this so I can be educated.

~~~
ghufran_syed
Some info regarding possible harms of prostate cancer screening:
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5485506/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5485506/)

Relevant snippet: ‘The potential gains of screening are opposed by reduced QoL
related to diagnostic biopsies, burdensome cancer treatment, including radical
prostatectomy (RP), radiotherapy (RT), and androgen deprivation therapy (ADT),
and the frequent long-term treatment-related adverse events, including
erectile dysfunction (ED), urinary incontinence (UI) and bowel dysfunction
(BD) [12–14]. In addition, RP has a small risk of peri-operative death [12,
13].

Finally, since a substantial fraction of PCas shows late onset and slow
progression, overdiagnosis and overtreatment are common consequences of
screening, especially when it is performed repeatedly or in men with
relatively short remaining life expectancy due to age or life-shortening co-
morbidity. Overdiagnosis and overtreatment are difficult to assess in
empirical studies, because it would require a lifelong follow-up of men
randomized to no screening and various screening options in a study without
migration bias.“

~~~
mikeash
Those sound like consequences of improper reactions to screening results, not
consequences of screening. The solution should be to make better decisions
with the results.

~~~
ghufran_syed
As long as we are dealing with humans, “improper reactions” to screening
results _are_ a consequence of screening :)

~~~
mikeash
Ok, but we should still separate our improper screening due to inevitable
mistakes from improper screening due to not having good procedures in place.

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heavymark
The doctor says buy it if you think its ‘nifty’ but do bit buy it for health
since it will not make you healthier. That’s crazy, it will certainly not make
every person healthy still like a personal trainer it cant make you do
anything but it can certainly encourage much healthier habits as it does for
millions of people like myself with real world tangible results. He dilutes
his more valid concern about his belief of saving lives from AFIB may or may
not outweigh the inconvenience false postives could cause.

~~~
DanBC
Do we have any evidence that these devices lead to long lasting changes? We
know that fitbit doesn't.

Or, better, that they lead to reduction in all cause mortality or reduction in
days lost to disability?

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malshe
What’s the source for 10% specificity? I couldn’t find any article that said
this was the case. In fact the only article that mentions any numbers is
written by Quartz and says this: “Cardiologists were able to read 90% of the
total readings, although about 10% of them were unreadable.” That’s not false
positive.

~~~
avip
He did not source it directly, but looking at some ROC curves from AF
detection publications the numbers seem completely reasonable.

------
emmanuelindex
I suppose this doctor will prescribe you to not use all new medical tools
available in case they might find something. I don't understand the logic.
Having mass adoption tools to check your health is the future. This will never
be 100% accurate, but like medicine and doctors will never be.

~~~
eli
Yes, doctors and health organizations routinely advise patients not to get
more tests than they need. A PSA test is cheap and easy to administer but the
consensus is that risk of false positives (among other reasons) outweighs the
benefits of finding prostate cancer among young men at low risk.

------
avip
For reference, FDA clearance of Apple watch as class II over-the-counter ECG
device
[https://www.accessdata.fda.gov/cdrh_docs/pdf18/DEN180044.pdf](https://www.accessdata.fda.gov/cdrh_docs/pdf18/DEN180044.pdf)

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MBCook
I’m still not clear on this, perhaps someone can enlighten me: does the watch
attempt to do an ECG whenever it can? Or is it something you have to
explicitly trigger?

I feel like it must be the first one otherwise people wouldn’t be arguing
against it.

~~~
manicdee
The watch monitors heart rate all the time. If it detects some symptoms of
a-fib (i.e.: irregular heartbeat) it will prompt the user to use the ECG
feature.

~~~
MBCook
Ah, that’s the trick. It prompts for the ECG if it thinks something is wrong
based on the regularity of the heartbeat sensor.

Thanks!

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dontreact
As consumers we should be demanding to know the sensitivity and specificity of
such health products. Doesn't seem responsible of Apple to market such
products without that information.

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doe88
I understand his argument but better have a false positive than a false
negative in my opinion.

~~~
mentalhealth
This is manifestly not the case, and there are a large number of studies
showing why this is true (many linked elsewhere in this thread). Most people
do not have a good understanding of the risks associated with ongoing medical
testing/medical visits.

A hopefully not-too-inaccurate analogy might be if you heard a strange sound
while driving your car, and took it into your mechanic, whose shop gets paid
more the more tests they do and the more labor they put into fixing your
potential non-problem, and they're potentially liable if anything later goes
wrong that could be traced to that sound. Think about where the systemic
incentives lie.

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coldtea
To gain some free publicity by stating the obvious which was already accounted
for?

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gumby
Paywalled, and not in the .is archive.

~~~
candylifter
You can easily get around Medium's paywall by opening in incognito window

~~~
anothergoogler
You can also use a script blocker. Medium's site is annoying enough I've
disabled all of their JS with uMatrix. Most journalism paywalls are half-assed
JS-dependent paper tigers, and I don't know why they befuddle so many
"hackers" here.

------
dhnsmakala
I'm not a heart doctor. Here's why I am not wary of the Apple Watch:

1.

At a societal level, perhaps false positives during screening put undue load
on the medical system. But as an individual, it makes sense for me to screen
for anything that does not take too high of an effort. If there is a false
positive, it will be snuffed out in the next test.

2.

Here is a little thought experiment. Lets say the false positive rate is 1%,
and you screen 100 people. Then, your total number of tests including repeated
tests on false positive subjects will be ~101 on average (the chance of 2 or
more false positives is low enough to ignore).

As long as the screening itself is not too much of an effort, then in fact
false positives don't add that much load to the system.

So, we should be seeking additional methods for widespread screening rather
than worrying about false positive rates.

\---

I also find the doctors assumption of 10% false positive rates to be a little
self serving in his argument. 1 in 10 people with an apple watch are going to
be have atrial fibrillation detection? Doubt it.

~~~
TeMPOraL
That would make some sense if we were talking about tests for long-term state,
but from what I understand, the test in question detects a potentially rare
and irregular _event_ happening. Which means, you can test yourself 100 times,
get one indication of a problem, and still not have enough information to be
confident that it was a false positive.

