Dr David Tuller: Dutch Study Links PEM in Long Covid to Biological Abnormalities

[Countrygirl]

Trial By Error: Dutch Study Links PEM in Long Covid to Biological Abnormalities​

2 Comments / By David Tuller / 9 January 2024

By David Tuller, DrPH

A new study in Nature Communications, called “Muscle abnormalities worsen after post-exertional malaise in long COVID,” caused a stir after it was published last week. The investigators identified significant biological differences after an exercise challenge between long Covid (LC) patients with post-exertional malaise (PEM) and matched healthy controls who had recovered from acute bouts of COVID-19.

The study, which was conducted by a team of Dutch investigators, has received lots of media attention as well as buzz among patients, physicians and other researchers. It has also gotten some polite pushback from Professor Alan Carson, a neurologist and a leader of the movement to increase awareness of functional neurological disorder (FND) as well as a long-time associate of Professor Michael Sharpe, a co-author of the discredited and arguably fraudulent PACE trial. Professor Carson weighed in on X—formerly known as Twitter—and raised two issues, both of which seemed to be irrelevant and non-responsive to the actual findings. As a result, his comments seemed like non-sequiturs and left the impression that he hadn’t read or understood the research in question.

It is not surprising that Professor Carson might want to raise concerns about a study documenting biological differences between long Covid patients and healthy controls. He and his colleagues have been pushing the theory that many manifestations of long Covid are “functional”—that is, driven not by underlying physiological dysfunctions but by, among other factors, anxiety, depression, excessive focusing on symptoms, deconditioning, and disrupted brain networks. A necessary corollary of this argument is that biomedical research cannot identify pathways that adequately explain the extent of the reported symptoms............

 

[datadragon]

This research also confirms the similar findings from the NIH that PEM is linked to lowered functioning of the mitochondria of the muscle (high WASF3 levels can lead to that), while the researchers in this new study plan to further examine whether the same muscle alterations can be found in other post-infectious patients to hopefully uncover the cause of these changes in the muscle, leading to proof of concept studies for treatment. The pathophysiology of post-exertional malaise (PEM) in long covid includes an acute exercise-induced reduction in skeletal muscle mitochondrial enzyme activity, an increased accumulation of amyloid-containing deposits in skeletal muscle, signs of severe muscle tissue damage, together with a blunted exercise-induced T-cell response in skeletal muscle.

This research also finds that the fatigue experienced by those with long COVID has a physical cause.

For this study, Prof. van Vugt and her team recruited 25 people with long COVID and 21 healthy control participants. They were all asked to take a cycling test for approximately 15 minutes, that was designed to push them to maximum exertion.

According to researchers, the cycling test caused a worsening of symptoms in the participants with long COVID, known as post-exertional malaise, resulting in worsening of fatigue for up to 7 days after. Scientists examined blood and muscle tissue samples from all participants both one week before the cycling test and one day after.

They found various abnormalities in the muscle tissue of the participants with long COVID, including lowered functioning of the mitochondria of the muscle. Known as the “powerhouse of the cell,” mitochondria are responsible for making the energy needed to power the body’s cells.

“So, the cause of the fatigue is really biological,” Prof. van Vugt explained. “The brain needs energy to think. Muscles need energy to move

 

[Rufous McKinney]

Back when I worked, and had alot of 3 am drama, the brain activity would leave me starving. In other words, how many calories did I use up just lying here not sleeping and not brain cleansing? Id be ravenous.