Cerebral Blood Flow Is Reduced in Severe ME/CFS Patients During Mild Orthostatic Stress Testing. van Campen et al. 2020

[John Mac]

Introduction: In a study of 429 adults with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), we demonstrated that 86% had symptoms of orthostatic intolerance in daily life. Using extracranial Doppler measurements of the internal carotid and vertebral arteries during a 30-min head-up tilt to 70 degrees, 90% had an abnormal reduction in cerebral blood flow (CBF).
A standard head-up tilt test of this duration might not be tolerated by the most severely affected bed-ridden ME/CFS patients. This study examined whether a shorter 15-min test at a lower 20 degree tilt angle would be sufficient to provoke reductions in cerebral blood flow in severe ME/CFS patients.

Methods and results:
Nineteen severe ME/CFS patients with orthostatic intolerance complaints in daily life were studied: 18 females. The mean (SD) age was 35(14) years, body surface area (BSA) was 1.8(0.2) m2 and BMI was 24.0(5.4) kg/m2.
The median disease duration was 14 (IQR 5–18) years. Heart rate increased, and stroke volume index and end-tidal CO2 decreased significantly during the test (p ranging from <0.001 to <0.0001). The cardiac index decreased by 26(7)%: p < 0.0001. CBF decreased from 617(72) to 452(63) mL/min, a 27(5)% decline.
All 19 severely affected ME/CFS patients met the criteria for an abnormal CBF reduction.

Conclusions: Using a less demanding 20 degree tilt test for 15 min in severe ME/CFS patients resulted in a mean CBF decline of 27%. This is comparable to the mean 26% decline previously noted in less severely affected patients studied during a 30-min 70 degree head-up tilt. These observations have implications for the evaluation and treatment of severely affected individuals with ME/CFS.

https://www.mdpi.com/2227-9032/8/2/169

Looks like this study is related to this one discussed here:
https://www.s4me.info/threads/cereb...n-or-tachycardia-van-campen-et-al-2020.13583/

 

[John Mac]

This is comparable to the mean 26% decline previously noted in less severely affected patients studied during a 30-min 70 degree head-up tilt. These observations have implications for the evaluation and treatment of severely affected individuals with ME/CFS.

I wonder if they have checked whether the less severe patients also display the same decline in this reduced test?

 

[lunarainbows]

Gosh. I’m so glad someone is doing these studies. This is probably why I and many others who are severe can’t stay upright. I wouldn’t be able to do 15 mins yet, more like 2-3 minutes..I wish research could propose a mechanism for why this happens & then a treatment for us... not being able to stay upright is the hardest thing and something I never in my life imagined I would lose. It stops you from doing pretty much most things in life.

 

[lunarainbows]

And something I didn’t realise on my first skim reading:

In the first study (less severely affected patients) it was a 70 degree tilt for 30 minutes.

Here it’s only 20 degrees tilt for 15 mins for severe patients. That’s a tiny tilt compared to the first study.

I mean... I think this is a very important finding in general.

Surely there’s only a few reasons this can happen, and oxygen would drop in people’s brains?

Issues with heart
Issues with lungs
issues with oxygen / red blood cells,
Issues with blood vessels themselves like if they’re restricting and reducing blood from flowing..
Or other issues I’m not thinking of (as I don’t know the field)...

I don’t know what else but couldn’t this be a relatively simple task to find out why? Am I missing something? I find it puzzling that something so big has been left out so far.

And, could a similar thing be happening in other parts of our body?

 

[cassava7]

Surely there’s only a few reasons this can happen, and oxygen would drop in people’s brains?

Issues with heart

Issues with lungs

Dr Systrom is looking into heart preload failure by using invasive CPET. His findings have been conclusive so far.

issues with oxygen / red blood cells,

Hopefully the red blood cell deformability experiment at Stanford can tell us more.

Issues with blood vessels themselves like if they’re restricting and reducing blood from flowing..

I think Claus Wirth is investigating this with Carmen Scheibenbogen.

 

[lunarainbows]

Dr Systrom is looking into heart preload failure by using invasive CPET. His findings have been conclusive so far.

Hopefully the red blood cell deformability experiment at Stanford can tell us more.

I think Claus Wirth is investigating this with Carmen Scheibenbogen.

Thank you, well that is promising. So it’s not just one thing then!

 

[lunarainbows]

Dr Systrom is looking into heart preload failure by using invasive CPET. His findings have been conclusive so far.

Hopefully the red blood cell deformability experiment at Stanford can tell us more.

I think Claus Wirth is investigating this with Carmen Scheibenbogen.

edit, having gone through those studies (& realised I’ve looked at some of these before!):

The third paper is a hypothesis based on what autoantibodies & blood vessel systems do in the body. Which is really interesting. But not yet any investigations eg they haven’t done structural imaging or anything to show that indeed these blood vessels are constricting/dilating, unless I missed that (I read the simmaron write up). In the brain for example a near 30% drop at a tilt of 20 degrees within 15 mins is very significant indeed & there must be something significant causing it.

Preload failure happens yes after exercise & the testing Systrom did, but in this study, there is something that happens just from lying still & then lifting your head/body up.

Is there a way to identify whether blood vessels actually are constricting / dilating at that point, or what is actually happening when the head is lifted and kept upright (through for example, blood vessel imaging)?

 

[Hoopoe]

I'm convinced that during postural changes in ordinary daily life, I can feel the blood redistributing itself. It feels like a weight that shifts downwards through the body, following postural changes with a delay of 1-2 seconds. The sensation this creates in the head is unpleasant and actually always present in some form.

This is also stressful for the body and certain repeated movements are a quick way to induce weakness, dizziness, malaise and visibly altered gait. I suspect that merely staying upright or sitting causes significant fatigue due to this blood distribution issue.

 

[rvallee]

Now I'm no fancy city lawyer and maybe I don't know anything about anything but it sounds like reduced blood flow to the brain may not be optimal for health and performance. With being able to stand up being somewhat important to functioning and everything.

Is that bad? It sounds bad. Lots of people seem to think otherwise. Maybe it's just bad thoughts that keep the blood away. Yes, that's definitely a more rational explanation, psychosocial and all that.

I really hope to see more of that, this is important work. With a reliable methodology this could be a significant diagnosis measure of physical impairment. Orthostatic intolerance and dysautonomia in general seem to be very prevalent in COVID-19 and some of the most debilitating symptoms so it will be a frequent occurrence at clinics. And of course nearly everyone is dismissed with anxiety and "it's all in your head". Well, kind of. Right location, wrong reason.

 

[Marky]

I like these studies, its pretty concrete. Can it be explained by deconditioning though? Anyone know?

 

[Liessa]

I like these studies, its pretty concrete. Can it be explained by deconditioning though? Anyone know?

Well there was this earlier study where they found differences in CI and SV to be the same irregardless of severity and accompanying activity level (with mild patients doing a lot more steps per day and thus being less deconditioned, etc).

https://gavinpublishers.com/article...-volunteers-are-not-related-to-deconditioning

 

[Marky]

Well there was this earlier study where they found differences in CI and SV to be the same irregardless of severity and accompanying activity level (with mild patients doing a lot more steps per day and thus being less deconditioned, etc).

https://gavinpublishers.com/article...-volunteers-are-not-related-to-deconditioning

Perfect! Ive actually read that one before haha #brainfog

 

[Mithriel]

Some thoughts.

When you stand up, blood can only reach the brain against gravity by using active processes. If we have low levels of ATP this might not be very efficient in us. The blood is squeezed by the leg muscles and our muscles are not very efficient so they won't work so well.

Compression socks and exercise can help POTS because they make the leg muscles work more efficiently. Deconditioning weakens these muscles and that is probably one of the reasons that the very severe have so much trouble but the processes that made them so severe they became deconditioned are still at work. I was unable to stand without feeling ill even when I was very fit.

A while ago work was done that showed our blood vessels were stiffer than normal which might be involved in the problem. The same team found that acetylcholine, which opens the blood vessels, is not cleared as quickly in ME patients as normal. Since the blood vessels narrow to squeeze blood up to keep the brain supplied that could be important. If the narrowed blood vessels can't carry enough deformed red blood cells that's going to make everything worse.

The hypothalamus was always thought to be damaged in ME and that is the part of the brain that tries to keep homeostasis in the body. We have trouble with temperature control and sugar control so the job of sending a signal to the blood vessels to work the blood to the brain could be broken as well.

Whether it is confirmed or not, these findings match patient experience and that is the direction all research should take.

 

[Mij]

I think the problem resides in the cardiovascular system?

 

[Trish]

The problem for the very severe could also relate to of necessity spending their time in bed horizontal. So their systems adjust to that as a normal state, and it can't adjust so well to pumping more blood to the head when the head is raised on a slope.

I think healthy people who have stayed horizontal for many weeks on the aerospace research found they went dizzy and passed out when they were first moved towards upright but it was a transient effect and the body adjusted back within days.

This paper lists orthostatic hypotension as a complication of prolonged bed rest:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2379624/

 

[lunarainbows]

The problem for the very severe could also relate to of necessity spending their time in bed horizontal. So their systems adjust to that as a normal state, and it can't adjust so well to pumping more blood to the head when the head is raised on a slope.

I think healthy people who have stayed horizontal for many weeks on the aerospace research found they went dizzy and passed out when they were first moved towards upright but it was a transient effect and the body adjusted back within days.

This paper lists orthostatic hypotension as a complication of prolonged bed rest:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2379624/

I don’t think it’s this, though, and not as the major driver.

When I was first becoming ill, I was upright for pretty much 16 hours a day (going into university, travelling etc). However I started to feel extremely unwell when upright. Even then this feeling of low oxygen was there, this sense of I am about to pass out and I feel dreadfully sick.

When I was in the train on the way there I would try to lean my head back or allow it to flop down a bit or lie horizontal across the train seats. When I wasn’t able to do that, I would feel really ill. When I got into university I would struggle with staying upright and once in a while lie down for a few seconds. As soon as I lay down for those few seconds or minutes, I would feel much more “restored”, which I imagine may be the oxygen flowing back to my brain, allowing me to go back upright again (although I felt ill doing it), until I then needed to be horizontal. At that point in my illness there was absolutely no bed rest, no deconditioning. But I recognise those symptoms still - because now I have those exact same symptoms, that exact same feeling - but it’s just all the time.

I feel that it is a condition of the actual illness, that some particular thing is going wrong in severe ME - much worse than in mild or moderate ME - rather than the fact we have been in bed for a long time.

 

[Trish]

I get what you are saying LR, and I had the same experience of finding it difficult to be upright, for long even when mild, and it's much worse now. But I am concerned that for those with severe ME it could just be attributed to prolonged rest, not as something specific to ME.

 

[unicorn7]

Interesting study!
I think this just complements the last study of van Campen where 90% of ME/CFS patients has OI symptoms and less blood flow to brain and body, most WITHOUT POTS.

They also found that there is no difference between mild and moderate patients. Patients who did 8000 steps a day, still had less blood flow to the brain. So definitely NO deconditioning.

I went to their clinic, because I was curious. I don't have POTS and I didn't think I had OI at all. The table tilt test was pretty awful, I got all my symptoms on that table and the bloodflow to my brain went down 33% when turned up. Blood flow to the body went down 25%.

 

[Wonko]

Where did all the blood go (-33% and -25%), if it wasn't in your brain or your body?

 

[unicorn7]

It's not the amount of blood, but it's the blood flow. They constantly measure heart rate, stroke volume index and end tidal CO2. They measure the diameter of the arteries with the ultrasound.