Hemodynamics During the 10-Minute NASA Lean Test: Evidence of Circulatory Decompensation in a Subset of ME/CFS Patients-Lee,Unutmaz,Bateman May 2020

This preprint is under consideration at Journal of Translational Medicine. Preprints are preliminary reports that have not undergone peer review. They should not be considered conclusive, used to inform clinical practice, or referenced by the media as validated information.

https://www.researchsquare.com/article/rs-28631/v1

 

Is it possible that pyridostigmine could help early on in the illness, but is ineffective later?

 

For those wanting a quick read just look at table 2. For example the first line in table 2
POTS or OH any time sequence: HC=49%, ME=54%.

I was very surprised by the amount of response to measures Healthy Controls had. I would have liked to see a breakdown showing orthostatic hypertension as well. I'm disappointed there wasn't a bigger separation between ME patients and healthy controls.

Hopefully the Solve ME sponsored study of "Hours of Upright Activity" will have sensor data for both healthy controls and patients that can show a greater separation between groups than the Nasa Lean Test. This paper only had individual self reported estimates for HUA in ME patients.

EDIT : Here is table 2

 

There is an interesting reader comment.

 

From the article:

Isn't this the same thing that Dr. Systrom is finding when he reports "preload failure" in ME/CFS patients?

 

That's probably the reason why they added that statement

 

Study now published
https://translational-medicine.biom...mpaign=BSCN_2_DD01_CN_bmcso_article_paid_XMOL

 

So this is a large study with 150 ME/CFS patients that found no statistically significant difference in the rate of POTS between ME/CFS patients and controls. This was mostly due to the high rate of POTS in the control group (33%).

Another large study with more than 400 patients, also found no statistically significant difference in the rate of POTS between ME/CFS patients and controls. However, in contrast to this study by the Bateman Horne Centre, they reported very low rates in the ME/CFS population (5.7%).

Perhaps researchers need to start thinking about other ways to explain OI in ME//CFS than in terms of hemodynamics?

 

https://www.s4me.info/threads/cereb...n-or-tachycardia-van-campen-et-al-2020.13583/

In this paper the majority of PWME had normal HR/ BP.
I think Barnden found that autonomic centres in brainstem misfired immediately on sitting up which seems too fast for a haemodynamic response.
OI occurs in other neurological disorders without HR/BP changes.

 

I have a sensation in my head that is the very similar as the one that can be felt by someone that suddenly stands up after lying down and then feels faint and dizzy. This feeling is always there and not as intense as the one that occurs when suddenly standing up.

I'm not sure if I still meet the POTS diagnostic criteria (30 bpm increase when standing). I think I clearly had POTS (with emphasis on the tachycardia). This abnormal reactivity of the heart rate has improved over the past 5 years while other aspects of orthostatic intolerance have changed little.

I think it's an issue of insufficient blood getting into the head or something similar. I would have said it's low blood pressure if I didn't know my blood pressure was mostly in the norm (low-normal but nothing bad).

 

Yes, maybe many false negatives?

https://www.frontiersin.org/articles/10.3389/fped.2018.00349/abstract

I'm always weary when Knoop en van der Meer are involved

 

If I understand correctly, that study criticizes protocols that put persons only 2 or 5 minutes in an upright position while testing for POTS. The studies I quoted both used the 10-minute protocol.

The biomedical studies done by Megan Roerink look alright.

EDIT: there is also an evident reason to be skeptical of positive findings of POTS namely, selection bias. The clinic by Van Campen/Visser, for example, is known to test for POTS and to prescribe medication for it, so ME/CFS patients with heart or other hemodynamic issues might be overrepresented there.

 

Also the Roerink did 10 minutes? Sorry didn't read. Head not working!