Prospective Evaluation of Autonomic Dysfunction in Post-Acute Sequela of COVID-19, 2022, Sameer M Jamal et al

[Mij]

Abstract

Background: Patients with PASC often report symptoms of orthostatic intolerance and autonomic dysfunction. Numerous case reports link Postural Orthostatic Tachycardia Syndrome (POTS) to PASC. No prospective analysis has been performed.

Objective: We performed head-up tilt table (HUTT) testing in symptomatic Post-Acute Sequela of COVID-19 (PASC) patients to evaluate for orthostatic intolerance suggestive of autonomic dysfunction.

Methods: We performed a prospective, observational evaluation of patients with PASC complaining of poor exertional tolerance, tachycardia with minimal activity or positional change, and palpitations. Exclusion criteria included pregnancy, pre-PASC autonomic dysfunction or syncope, or another potential explanation of PASC symptoms. All subjects underwent HUTT.

Results: Twenty-four patients with the described PASC symptoms were included. HUTT was performed a mean of 5.8 ± 3.5 months after symptom onset. Twenty-three of the 24 had orthostatic intolerance on HUTT, with 4 demonstrating POTS, 15 provoked orthostatic intolerance (POI) after nitroglycerin, 3 neurocardiogenic syncope, and one orthostatic hypotension. Compared to those with POTS, patients with POI described significantly earlier improvement of symptoms.

Conclusions: This prospective evaluation of HUTT in PASC patients revealed orthostatic intolerance on HUTT suggestive of autonomic dysfunction in nearly all subjects. Those with POI may be further along the path of clinical recovery than those demonstrating POTS.

https://pubmed.ncbi.nlm.nih.gov/35381331/

 

[Hutan]

It's open access, although it took me a little while to find a link to a Journal pre-proof. Some bits that I thought were interesting:

Patients were also excluded for pregnancy, pre- COVID-19 history of syncope, or pre-COVID-19 autonomic dysfunction by symptoms or diagnosis

So, patients tested did not have the symptoms prior to the Covid-19 infection. They were however selected on the basis of having a confirmed Covid-19 infection and the patient reporting tachycardia with minimal activity or positional change and 'poor exertion intolerance' subsequent to that. Poor exertion intolerance wasn't defined in more detail. The tilt table test was done at approximately 6 months.

Figure 1 demonstrates subject responses to HUTT. Four patients demonstrated POTS, 15 demonstrated POI, 3 had neurocardiogenic syncope, one had orthostatic hypotension, and one response was normal. In addition to the 3 patients exhibiting neurocardiogenic syncope alone, 1 of 4 POTS patients and 5 of 15 patients with POI also developed neurocardiogenic syncope during HUTT.

They report 23 out of the 24 having signs of orthostatic intolerance. The "POI" is provoked orthostatic intolerance - i.e. after the administration of 0.4mg sublingual nitroglycerin (NTG) tablet with continuation of a 15-minute observation component while at a 70 degree tilt. I don't know how healthy people respond to such a stimulus. The study doesn't have controls or tell us what percentage of healthy people have POI.

Both POTS and POI diagnoses required reproduction of a patient’s exact clinical symptoms during HUTT with rapid improvement upon return to a supine position.

At 9 months, all of the people with provoked orthostatic intolerance (edit - at 6 months) reported symptoms had gone or were improving.

Regardless, the development of POTS after viral and bacterial illness is well established 19 beginning with the earliest description of the disorder 20.

Our investigation adds to this emerging body of knowledge, suggesting in a prospective manner that nearly all individuals with the described PASC symptoms are impacted by OI that suggests autonomic dysfunction.

In our study, patients were excluded for history of syncope before PASC development. While only one patient described syncope as a symptom of their PASC, neurocardiogenic syncope was observed on HUTT in 9 patients.

I think this is an interesting preliminary study. It would be great to see a longitudinal study of people infected with Covid-19, with measures of orthostatic intolerance made monthly to see if such measures track the development of ME/CFS compliant Long Covid.