Trial Report Blood Flow To The Head Is Reduced in a Patient With Myalgic Encephalomyelitis With Confirmed Post-Exertional Malaise, 2024, Lee

https://cdn.shopify.com/s/files/1/0...0_ACSM_Workwell_Lumia_Poster.pdf?v=1719881896

Blood Flow To The Head Is Reduced in a Patient With Myalgic Encephalomyelitis With Confirmed Post-Exertional Malaise

Daniel Lee, Staci Stevens, Todd Davenport, Jared Stevens, Theresa Dowell and Mark VanNess. Lumia Health, Boston, MA and Workwell Foundation, Ripon, CA

Abstract

Results: Lumia Blood Flow Index compared to 2-Day CPET Results Reduced Cerebral Blood Flow (CBF) may underlie the pathophysiology of Post- Exertional Malaise (PEM) in Myalgic Encephalomyelitis (ME).

PURPOSE:

A novel inear device provided by Lumia Health was used to measure blood flow to the head via the external carotid artery as a proxy for CBF. The goal was to determine if there would be measurable differences in Flow during PEM induced by exercise testing (CPET).

METHODS:

One patient with ME and one control subject underwent 2-day CPET to induce PEM. Lumia’s Flow Index was measured supine and during an orthostatic challenge (10 min standing) before CPET on both days.

RESULTS:

CPET results confirmed PEM in the ME patient, with a 34% reduction in Work at the Anaerobic Threshold (AT). Relative to the Day 1 supine baseline, the ME patient experiencing Day 2 PEM had a large 17% reduction in supine Flow and a 23% reduction during orthostasis (10 min standing). In contrast, the control subject did not demonstrate PEM (1% reduction in Work at AT) and had a small 5% reduction in supine Flow on Day 2 relative to the Day 1 supine baseline. The control subject did not conduct the orthostatic challenge.

CONCLUSION:

Diminished Blood Flow during PEM may provide an objective mechanism underlying patient symptomatology for ME patients. The Lumia device has the potential to serve both as a diagnostic biomarker and as a biofeedback tool for ME patients to better self-manage their symptoms.

 

https://lumiahealth.com/blogs/news/reduced-supine-blood-flow-to-head-in-post-exertional-malaise-pem

Reduced Blood Flow to Head in Post-Exertional Malaise
JUNE 30, 2024 SHIVANI UGRIN


Reduced Cerebral Blood Flow (CBF) -- including while lying down -- may underlie the pathophysiology of Post-Exertional Malaise (PEM) in Myalgic Encephalomyelitis (ME).

Lumia Health recently collaborated with Workwell Foundation on a 2-day CPET pilot research project, and the surprising findings were shared as a poster session at the American College of Sports Medicine (ACSM) annual conference.




EXPLORE THE FULL SIZE POSTER HERE

PURPOSE: A novel in-ear device provided by Lumia Health was used to measure blood flow to the head via the external carotid artery as a proxy for CBF. The goal was to determine if there would be measurable differences in Flow during PEM induced by exercise testing (CPET).

METHODS: One patient with ME and one control subject underwent 2-day CPET to induce PEM. Lumia’s Flow Index was measured supine and during an orthostatic challenge (10 min standing) before CPET on both days.

RESULTS: CPET results confirmed PEM in the ME patient, with a 34% reduction in Work at the Anaerobic Threshold (AT). Relative to the Day 1 supine baseline, the ME patient experiencing Day 2 PEM had a large 17% reduction in supine Flow and a 23% reduction during orthostasis (10 min standing). In contrast, the control subject did not demonstrate PEM (1% reduction in Work at AT) and had a small 5% reduction in supine Flow on Day 2 relative to the Day 1 supine baseline. The control subject did not conduct the orthostatic challenge.

CONCLUSION: Diminished Blood Flow during PEM may provide an objective mechanism underlying patient symptomatology for ME patients. The Lumia device has the potential to serve both as a diagnostic biomarker and as a biofeedback tool for ME patients to better self-manage their symptoms.



This collaboration with Workwell Foundation was a n-of-1 "proof of concept" study to help illuminate the nature of Post-Exertional Malaise in people with Myalgic Encephalomyelitis. A subsequent larger study is being planned to verify this phenomenon in more individuals experiencing PEM.

 

N = 1 doesn't "prove" anything.

Then why not wait until that study is completed before going public?

 

Seems to be a poster so presumably the work someone does in a bachelor or master thesis to learn how to do things, rather than publishing something meaningful.

 

I wasn't under the impression that an ear was the same thing as a head, medically speaking, and even if it wasn't N=1, if it was N=678599383, then all that might have been shown is that there is a reduction in blood flow to an ear (one of, out of a possible 2) when a person is in PEM, maybe.

Sorry to be so harsh but really.......N=1?

 

If that actually goes through, beats most ME studies who find something interesting in a tiny cohort and then never get replicated.

Agree with the in ear ≠ in head comment though!

 

It’s not the ear it is the vein that is being used to track blood flow to the brain which is only found in the left ear. It is the closest that can be had outside the brain itself.

Presentations, I believe, are to attract funding for the kind of research we all want and need. I expect that will move more quickly when the device gets through the betta trials and is produced in large enough numbers to be accessible to researchers.

 

I am not aware of a vein that drains the brain only present on the left side?

Pictures on Google seem to confirm my memory that an internal jugular vein comes out through the jugular foramen and passes close to the ear on both sides. Measuring flow rates in IJV would seem a pretty good way to estimate brain blood flow. My only worry is that the measurements may be pretty sensitive to slight differences in transducer position over time, perhaps with position too.

 

Poster presentations are generally because the quality of content is not sufficient to justify a proper talk, because you are a junior researcher or simply because you aren't friendly with the right people that would give you the space for a proper talk. It's about spreading the word and putting yourself out there to connect with others. I doubt it has too much influence on funding.

 

Perhaps a confusion of the vagus nerve (which I seem to recall going through the left ear) and a vein?

 

According to their homepage they use the External Carotid Artery.

 

There are two of them too!

It could well be internal carotid but of course that misses the vertebral supply and the proportion of each may change with neck posture. I also wonder if the carotid being muscular and capable of change in calibre it may not be so easy to get a reliable reading just from flow Doppler, if that is what this is.

Edit: Uh-uh! so it's external carotid, which doesn't even supply the brain. that seems pointless. You might just as well measure blood pressure.

 

No. It does not supply the brain. They never claimed it did. It does however measure blood getting to that part of the body. There is no non-invasive way to measure blood to the brain.

 

On the Lumia website they say they have compared the device to transcranial doppler (TCD). Which I guess is more accurate at measuring cerebral blood flow outside of a PET scan.

Despite the hype (and lack of easily accessible scientific literature on their site so we can see these TCD comparisons for ourselves...) They do say it is not a diagnostic tool or medical device but it apparently will "empower pwME, pwPOTS etc to manage their symptoms".

Thankfully, they do note that they have a lot of scientific research to do, and this is the first pilot trial.

 

We can measure cerebral blood flow with CT, MRI, PET and ultrasound. This is a proxy and a wearable. It won't be super accurate.

Four arteries supply the brain. Ignoring the input from the two vertebral arteries, left and right common carotid arteries (CCA) split to internal (ICA) and external (ECA) branches. ICA supplies brain, ECA supplies scalp, meninges, face, thyroid etc.

Via cerebral autoregulation, the brain controls blood flow (CBF) independent of changes in mean arterial blood pressure (MABP), or more correctly cerebral perfusion pressure (CPP).

CPP = MABP - ICP (simplified, ICP is intracranial pressure)
CBF = CPP x cerebral autoregulation (i.e. not "1:1" and dependent on cerebral vascular resistance)

Cerebral vascular resistance (CVR) depends on diameter and length of vessel and viscosity of blood.

If CBF drops with unchanged MABP/CPP then ICA flow must drop and so with CCA flow input unchanged, ECA will have relatively more flow diverted into its circuit. So measuring the posterior auricular arterial blood flow is an indirect measure of intracranial/cerebral blood flow.

See more detail at Deranged Physiology or Open Anesthesia.



Note the baseline difference between ME and HC (both supine, both HR 54): the pwME has higher ECA flows, which infers lower ICA flows. Low cerebral blood flow is being reported in multiple LC research cohorts.

Spoiler: Refs

Altered brain perfusion and oxygen levels relate to sleepiness and attention in post-COVID syndrome (2024, Annals of Clinical and Translational Neurology)

Reduced Cerebrovascular Oxygenation in Individuals with Post-Acute COVID-19 Syndrome PACS “long COVID” (2023, SpringerLink)

Long-term microstructure and cerebral blood flow changes in patients recovered from COVID-19 without neurological manifestations (2021, The Journal of Clinical Investigation)

Cerebral hypoperfusion in post-COVID-19 cognitively impaired subjects revealed by arterial spin labeling MRI (2023, Nature Scientific Reports)

Orthostatic Symptoms and Reductions in Cerebral Blood Flow in Long-Haul COVID-19 Patients: Similarities with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (2021, Medicina)

Brain Frontal-Lobe Misery Perfusion in COVID-19 ICU Survivors: An MRI Pilot Study (2024, Brain Sciences)

 

Encouraging PWME to deliberately exercise in order to get PEM does not seem ethical.

 

The alternative to publishing an n=1 study isn't usually an n=10 study, it's putting it in the file drawer so nobody ever hears about it. I welcome all data of all kinds and all sample sizes. Nobody sets out to do half-finished, under-populated, under-powered studies but logistics can get in the way. This is why we do replication and meta-analysis.

 

Now I am a bit confused. You claimed that it tracked a special left hand vein that tracks brain flow. The problem is that the external carotid (being measured) and the internal carotid (part supply to brain) are branches off the same main trunk (common carotid) so will compete for flow. All other things being equal (pulse and blood pressure) a reduction in flow in the external is quite likely to be a good sign of an increase in flow in the internal carotid. Closing off the external carotid would be a neat way to improve head of pressure to the brain and opening up of brain flow would tend to reduce external carotid flow.

It is possible that at least in some circumstance the external carotid reflects internal carotid flow but the whole point of research in this are is to study unusual circumstances in which we cannot predict that. So I wouldn't be interested in anything other than an actual measure of flow to the brain. I would have thought juguklar vein outflow might be better because I think there is only one way out, while, as SNTG says, there are two ways in.

I am not quite sure what you are saying there. Do you agree that a decrease in flow in the external branch would suggest an increase in cerebral blood flow?

 

Jonathan Edwards I clearly misspoke when I said vein. I am not a scientist or a doctor. I am a very, very sick person desperately trying to save myself. I am in the beta trials and can share my experiences as a sick person that’s all. I have been to their lab and met the people involved. I am personally impressed by what they are doing and we will see what happens after the researchers are able to complete their work. There is a website that does a better job than I can if you are interested.