People With Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Exhibit Similarly Impaired Vascular Function, 2023, McLaughlin+

People With Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Exhibit Similarly Impaired Vascular Function

Background
This study aimed to compare flow-mediated dilation values between individuals with Long COVID, Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), and healthy age-matched controls to assess the potential implications for clinical management and long-term health outcomes.

Methods
A case-case-control approach was employed, and flow-mediated dilation measurements were obtained from 51 participants (17 Long COVID patients, 17 ME/CFS patients, and 17 healthy age-matched controls). Flow-mediated dilation values were analysed using one-way ANOVA for between-group comparisons.

Results
Results revealed significantly impaired endothelial function in both Long COVID and ME/CFS groups compared to healthy age-matched controls as determined by maximum % brachial artery diameter post-occlusion compared to pre-occlusion resting diameter (6.99 ± 4.33% and 6.60 ± 3.48% vs. 11.30 ± 4.44%, respectively, both p < 0.05). Notably, there was no difference in flow-mediated dilation between Long COVID and ME/CFS groups (p = 0.949), despite significantly longer illness duration in the ME/CFS group (ME/CFS: 16 ± 11.15 years vs. Long COVID: 1.36 ± 0.51 years, p < 0.0001).

Conclusion
The study demonstrates that both Long COVID and ME/CFS patients exhibit similarly impaired endothelial function, indicating potential vascular involvement in the pathogenesis of these post-viral illnesses. The significant reduction in flow-mediated dilation values suggests an increased cardiovascular risk in these populations, warranting careful monitoring and the development of targeted interventions to improve endothelial function and mitigate long-term health implications.

https://www.amjmed.com/article/S0002-9343(23)00609-5/fulltext

 

Uses flow-mediated dilation, which is very similar to EndoPat used by other groups.

A significant problem (in drawing a comparison to HC) here are the large differences in weight/BMI between the ill and healthy patients, with the BMI for LC being at 34.19, for ME/CFS at 31.49, and for HC at 24.23. This alone can be responsible for explaining the differences observed (as well as differences in activity levels affecting vascular function) https://pubmed.ncbi.nlm.nih.gov/14769683/.

However, this is not an issue for the comparison ME/CFS vs LC where, as expected, significant overlaps can be seen. Unfortunately, a comparison to HC doesn't really seem possible (or maybe it does https://www.sciencedirect.com/science/article/abs/pii/S0167527300003818?).

 

This seems like a good contribution, replicating Fluge and Mella's Endothelial dysfunction in ME/CFS patients (2023). The key point as quoted above by @EndME is identical findings in ME and LC despite a much longer disease duration in the ME group. So a good argument against deconditioning which might be expected to worsen over time.

I couldn't see a good description of the inclusion criteria beyond "long Covid" and "ME/CFS", but the authors seemed to understand PEM etc well. I appreciated the reference to NICE 21 and comments about lack of inclusion of more severe patients.

 

I can’t manage to read this study, could someone tell me how would this be monitored? Are there any existing interventions at all, if so are they rare and expensive or more widely available?

warranting careful monitoring and the development of targeted interventions to improve endothelial function and mitigate long-term health implications.

 

If you already have LC damage done and or you can’t avoid getting infected because you're a disabled person who requires services and you’re neither wealthy nor healthy enough to isolate in a lovely cabin in the woods?

 

I was part of this trial. It was a one part of a bigger trial. They are planning to do a large scale trial and are seeking to secure funding.

It's almost conical that when I took my results to the GP. The doppler test result put me in the bottom 5 percentile of the population, he took one look at it and said 'I can't do anything with this, go back to them and maybe they can treat you'.

 

Yes, me too.

I wonder how many others here have secretly identified three or four friends or relatives who'd be a good match as their healthy control if they passed screening...?

 

They are looking for potential participants. It would involve 2 visits to a University in the West of Scotland. A week between visits.

The doppler was one day, one test. Included with other tests. Gait sitting standing etc.

I don't know what the significance is of a double visit.

I will post a contact email here when I get one. I should hear from Dr McLaughlan this week. She emailed me last week asking what the ME community would think about further trial. They are very keen to secure Scottish Government funding for this.

I will pass on any comment or opinion regarding the trial.

 

Obviously they may be able to get some ideas from the way DecodeME was set up (some of the approaches could potentially help even with a much smaller trial), but folk here might be able help by offering feedback – their research question, the way they hope to recruit, the screening tools, the reporting, etc? People would also be able to help walk them through how to make the visits to their centre as accessible as possible.

If the team has the resources to do any of that, even informal patient participation ought to help their case for funding.

 

ME Research UK summary:

https://www.meresearch.org.uk/impaired-endothelial-function-in-me-cfs-and-long-covid/

 

Recruited via social media, the study included 51 participants in total – 17 with ME/CFS, 17 with long COVID, and 17 healthy controls. The paper does not mention whether ME/CFS diagnoses were confirmed or, if so, which diagnostic/research criteria were used. Whilst the healthy controls were matched with the disease cohorts in terms of age, there were some substantial differences in body mass index (BMI), blood pressure, and heart rate between the groups.

The authors mention that to “reduce participant burden, participants were not advised to fast before the test”. Yet, they acknowledge that dietary intake immediately prior to flow-mediated dilation assessment can have a potentially confounding effect on the results.

As mentioned in the paper, it might be hypothesised that individuals with ME/CFS would have poorer vascular function than people with long COVID, due to a longer duration of post-viral illness and ‘multi-system deconditioning’ (which is known to reduce flow-mediated dilation). Yet, interestingly, there was no difference in flow-mediated dilation between participants with ME/CFS and those with long COVID. The authors state this could suggest that endothelial damage is experienced in the early post-viral phase, without a further reduction in flow-mediated dilation after this initial reduction, and that impairment in flow-mediated dilation is unlikely to be due to deconditioning.

 

A follow up study is starting soon. Two visits, double blind trial. Beetroot juice ingestion and doppler v's water and doppler.

No-COVID. West of Scotland University.

Was keen to take part but really not sure due to circumstances.

 

Sorry, it's a bit more complicated than that. And I didn't use proper terminology.

The effect of acute inorganic diatery supplementation on flow-mediated dilation in people with long-COVID and people with ME/CFS: A feasibility and pilot-study.

98% Concentrated Beetroot Juice 2% Lemon Juice.

2 x 70ml beetroot juice on one visit v's 2 x 70ml nitrate depleted beetroot juice. 2 visits.

 

Citrulene is a dietary supplement that has also been shown to improve vessel dilation. There are also prescription medications such as erectile dysfunction drugs that help vascular dilation.

My N=1 experiment with citrulene and beet root extract is that they may have improved vessel dilation but it increased orthostatic hypotension. Folks may want to try them though. They could potentially assist with energy production with more blood reaching working cells.

 

Thanks for that, I'll look into Citrulene. Ivabradine changed my existence. Really good, made a big difference.