Exploring the neurocognitive consequences of post-exertional malaise in myalgic encephalomyelitis, 2023, Moreau

https://www.jns-journal.com/article/S0022-510X(23)02051-8/fulltext

PV1412 / #1916| VOLUME 455, SUPPLEMENT , 122590, DECEMBER 2023
Exploring the neurocognitive consequences of post-exertional malaise in myalgic encephalomyelitis

• Corinne Leveau
• Iurie Caraus
• Anita Franco
• Alain Moreau

DOI:https://doi.org/10.1016/j.jns.2023.122590




Myalgic encephalomyelitis (ME) is a complex, debilitating and heterogeneous disorder. It affects over 500,000 people in Canada but remains poorly understood. People are affected with multi-systemic symptoms such as fatigue that is not alleviated by rest, pain, cognitive impairment and post-exertional malaise (PEM), which is considered as the hallmark symptom of ME. PEM is triggered by minimal mental or physical effort and exacerbates other symptoms. Our aim was to measure how individuals’ cognition can be impacted by the induction of PEM, and investigate the difference in cognitive response.

 

Cognitive impairement in ME/CFS, how to measure it and it's relation to PEM are largely unexplored so the title seems good. However, I can't read the paper since it isn't open access...

 

I agree: the title is promising, but we'll have to wait to see the quality of the research. Hopefully cognitive function will be measured by brain scans and/or quantitative tests rather than questionnaires.

 

Simple Reaction Time was found off quite a bit in me/cfs, might be worth looking at.

 

On PR, many of us tried an online reaction time test. Quite a few of us reported much higher than average performance. So, it doesn't seem to be a reliable response to ME. I expect that if someone wanted to write a paper showing that reaction time correlated with toenail fungus, they could set up a study and get results that shows that they are right, even though a properly done study would show no correlation.

 

From OMF's newsletter:

'Research Summary: From the Desk of Alain Moreau, PhD, Director of the OMF ME/CFS Collaborative Research Center at the University of Montreal & Corinne Leveau, MSc, Lead Author & PhD student at the OMF ME/CFS Collaborative Research Center at the University of Montreal:

“In this talk, I discussed the effects of post-exertional malaise (PEM) on people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Our team developed a standardized test lasting 90 minutes to induce PEM in ME/CFS patients using a mechanical arm stimulation with an inflatable cuff. We included both people with ME/CFS and sedentary healthy individuals in our study. Both groups had blood drawn and underwent cognitive testing before and after the PEM test.

Our initial findings indicate that ME/CFS participants experienced cognitive impairment after the PEM test, although a significant variation in individual responses was observed. This prompted us to divide the participants into three subgroups based on their cognitive responses.

These subgroups align with specific microRNAs (miRNAs), which are small molecules that regulate genes. Interestingly, these same miRNAs are linked to other neurological disorders, suggesting their potential role in cognitive function. Our future research will involve looking for more miRNAs and other molecules related to various aspects of cognition (like attention, memory, and executive function) in the context of ME/CFS. These results will contribute to a better understanding of the disease, particularly its impact on brain fog and other types of cognitive impairment.”'

 

I like that they're studying miRNAs related to brain function. I do wonder how well the serum level correlates with the levels in the brain. Do miRNAs pass the BBB with no loss? Are they not bound or broken down before reaching the blood? Do those characteristics vary (eg. miRNA 123 has a blood concentration of 80% of the level in the brain within 3 hrs, while miRNA 124 has only 4%, or some such thing)?