NIH: Decoding the Mysteries of Postural Orthostatic Tachycardia Syndrome

Quotes:

As a person living with POTS, Goff wants to see researchers focus more on why POTS happens. “I feel like current treatments aren’t really getting to the root problem, and I also worry about the effects of taking steroids long term,” Goff said. “I’d like to see possibly better treatments that get to the reason for the condition.” Raj agrees. “We still have an incomplete picture of the underlying mechanisms of POTS,” he said. “If we understand [the mechanisms] better, we can come up with better targeted treatments. We also need objective tests that clearly differentiate POTS from other distinct syndromes like chronic fatigue, myalgic encephalomyelitis, and fibromyalgia,” he added.

...
Recognizing the gap in the understanding and treatment of POTS, the NHLBI and the National Institute of Neurological Disorders and Stroke have issued a Notice of Special Interest to encourage researchers to submit proposals designed to answer fundamental questions about POTS. Initial applications are due June 5, 2021.

Decoding the Mysteries of Postural Orthostatic Tachycardia Syndrome

 

I spotted the article via a Tweet from Dysautonomia International, who says this is NIH's first news story on POTS.

 

From the article: "...potential association between POTS and iron deficiency...."

Interesting. A few on the Forum have indicated problems with iron levels. Just speculation, but might there be some form of absorption problem for some who have trouble with their iron levels.

Difficult to sort out POTS from ME. The cross over is perplexing.

 

Thank you to Dysautonomia International for assisting in bringing this very debilitating issue to the fore.

 

Good to see this

What do you reckon they mean when they talk about POTS in this context? Do they really mean only POTS, or do you think there's any chance they will be including other kinds of dysautonomia and orthostatic intolerance, such as neurally mediated hypotension/NMH for example?

 

From the glimpses I have seen, there seems to be a mostly exclusive focus on tachycardia, with very little attention to the rest. For now. But at least there's this verifiable thing that can be used in research. Nothing is believed until a machine says "yes". It will mostly catch POTS, leaving out many with milder dysautonomia, but at least it's the opposite problem with ME, focusing on the most severe sure is smarter than only dealing with the mild cases. Something tells me at least some of that interest is because of the possibility of myocarditis, I'm not sure how much it would fade if tests are clear but the symptoms remain...

I assume there will be focused interest once they find all about reduced blood flow to the brain and all that. I also wonder whether blood diffusion, generally speaking and I am probably using the wrong term here, can be measured? Surely that blood pooling in extremities must have a way to be measured? Yes it's visible but... there needs to be a number somewhere otherwise it doesn't factor in much.

I asked my GP years ago about POTS, either genuinely had not heard of it or pretended to. I had an appointment this week, mostly a waste of time, but she actually asked me about positional tachycardia. In passing, nothing else about it, just tachy and whether it happens positionally. She was surprisingly up to date with Long Covid, even knew about Moreau's research. Still mostly a waste of an appointment. Progress measured in Planck lengths per second...

 

Also interesting secondary POTS could be associated with thyroid conditions. Never heard of this. As well, the comorbidities are I think familiar to some on the Forum.

It would be great, to say the least if science found the mechanisms and links for these conditions.

 

It seems another bad muddle to me. One of those quoted focuses on the S for syndrome but I see no evidence for there being a specific syndrome that is worth the name POTS. For sure there is POT - postural orthostatic tachycardia. People with that may also have other problems - some may have ME. But bundling all these symptoms together under POT makes no sense to me. The idea of primary and secondary POTS confuses further. If POT is secondary it is clearly not POTS, if there is such a thing. And so on.

To me this is the sort of superficial journalistic ramble that we need to get away from. It says some people do well with exercise - so what is the evidence. What is the evidence for mineralocorticoids being a good thing? It just seems like window dressing to pretend that patients are being taken seriously. Diseases where patients are genuinely taken seriously get coverage with evidence-based material.

 

Someone does not understand that POTS is one of a feature of ME

 

Can we say with out current level of knowledge that POTS is a symptom of ME, or only that orthostatic intolerance is probably a relatively common symptom of ME? There seems to be some variation as to how orthostatic intolerance in ME presents.

Obviously for some their orthostatic intolerance is such that it meets the definition of POTS, but do we know how this relates to other situations where people’s symptoms meet the definition of POTS. For example what little I have read about POTS occurring in isolation seems to describe something that though very much overlapping also has different features including such as spontaneous remission.

We also are still a long way from knowing what is a symptom and what a cooccurring condition, possibly arising from a common cause or that in some way one is indirectly caused by the other. I personally regard my IBS and my migraines as symptoms of my ME, but they can also be symptoms of my food intolerances, which though post dating the onset of my ME may or may not in turn be a consequence of my ME. However, until we know more, how we define the relationships between symptoms and cooccurring condition is somewhere between speculation and personal preference.

However I welcome this article as the more we understand about POTS, hopefully the nearer we get to understanding orthostatic intolerance and both their relationship with ME.

 

This may help @Peter Trewhitt https://www.sciencedirect.com/science/article/pii/S2467981X20300044

 

Thank you, for this important link, I had previously read this, but had forgotten, though am not surprised by, how high, both the incidence of orthostatic intolerance and of POTS are in ME.

Certainly any one diagnosed with ME should be informed about the potential impacts of orthostatic intolerance, and regularly considered as to whether assessing them for POTS is appropriate.

 

From PubMed: Clin Auton Res.
. 2013 Aug;23(4):175-9. doi: 10.1007/s10286-013-0198-6. Epub 2013 May 30.
Low iron storage and mild anemia in postural tachycardia syndrome in adolescents
Imad T Jarjour 1, Laila K Jarjour
Affiliations

• PMID: 23720007
  
• DOI: 10.1007/s10286-013-0198-6

Abstract


Objective: We reported low iron storage in neurally mediated syncope (NMS). While reduced red cell mass indicative of anemia has been reported in POTS, iron indices and hemoglobin (Hb) data were not reported. We investigated whether POTS, like NMS, is associated with low iron storage and anemia.

Methods: Thirty two children evaluated in 2007 and 2008 for probable POTS by a standing or tilt test or both at Texas Children's Hospital were included in a retrospective study. We measured serum ferritin (SF) and Hb values. We defined iron deficiency as SF < 12 μg/L, low iron storage as SF ≤ 25 μg/L, anemia as low Hb values for age and sex, and POTS as ≥2 symptoms of orthostatic intolerance >3 months and increased HR of >30 BPM or HR of >120 BPM within 10 min of standing or 70° tilt.

Results: Twenty four children had POTS, ages 12-18 years, 17 (71 %) were females. Value range (median) of SF 2-289 μg/L (25), Hb 11.5-14.6 (12.5) in females and 12-15.9 g/L (13.6) in males. Patients with POTS, when compared with normal US pediatric population had higher prevalence of low iron storage (50 vs. 14 %), iron deficiency (25 % of teenage girls vs. 9 %, and 16 % of teenage boys vs. 1 %), and anemia (18 % of teenage girls vs. 1.5 %, and 43 % of teenage boys vs. 0.1 %).

Interpretation: Low iron storage and mild anemia are associated with POTS suggesting that low iron storage is a potentially pathophysiologic factor in both POTS and NMS.

Link here:

https://pubmed.ncbi.nlm.nih.gov/23720007/

We've made a thread for this study here:
Low iron storage and mild anemia in postural tachycardia syndrome in adolescents, 2013, Jarjour and Jarjour

 

Anyone know off the top of your head if POTS has PEM?

I agree with @Jonathan Edwards it's a muddle. It could be making things more confusing for ME researchers and the entire field.

It's confusing when I look at the POTS material (just mis-typed it as PITS ); it makes me wonder if I have something called POTS, as the major disease.

Though POTS is a symptom of ME, and so is NMH.

It seems to be all a question of which bicycle one is on...POTS or ME, or FM.

I think I'll stick with ME, as I have PEM.

(Although my OI is often dreadful.)

 

There's a fair bit of research in the field of POTS going back 20 years into questions like this, sub-groups were even identified depending on the blood flow and pooling types. They used a variety of methods to make these sorts of measurements, from memory certainly plethysmography, I think also some clever doppler techniques with lasers. Julian M. Stewart's group did a lot on this if you want to look them up.

 

This hits the spot. Where i live there is a POTS research group led by a cardiologist and unlike ME they won't tell you that it's psychosomatic, but at the end of the day all they do is tell the patients they will be cured if they exercise (if exercise makes you worse they tell you it's impossible and give you SSRis) and sometimes give beta blockers. They try to convince everyone that exercising works for these patients when in reality we know that for a large portion it doesn't. In diseases that get taken seriously (like say MS) there is a totally different kind of effort in finding treatments and the cause of disease.

 

I suspect that depends entirely on how some 'Delphic' group of 'experts' likes to define it.
For me this is the problem with the ICC definition of ME. It includes all sorts of stuff made up by 'experts' with no actual evidence for linking things together.

 

Unfortunately I've heard similar reports from patients attending a major teaching hospital autonomic unit in London - they catch POTS patients because of the nature of their clinic and probably only because they are forced to. They aren't the least bit interested in understanding or treating these patients.

However, you can go 10 miles down the road to an autonomic unit at a different hospital, where there is an active interest in POTS and the experience will be entirely different. They'll realise SSRI's are contraindicated for POTS, especially in those with a hyperadrenergic leaning. They'll have awareness of and do broad screening for the numerous underlying conditions that POTS associates with. They'll understand deconditioning is a minor factor and probably only secondary to an underlying disease process. They won't always recommend exercise, and when they do its usually only after pharmaceutical intervention has significantly improved the functioning. And most importantly: they don't discharge you.

 

"They aren't the least bit interested in understanding or treating these patients."

I was in a research study like this. More and more I find mean spiritedness goes along with incompetence.