Deconstructing post-exertional malaise: An exploratory factor analysis, 2016, Jason et al

[Andy]

Slightly confused, as Lenny Jason is saying that this was just published when the journal webpage says first published 2016, so I went with the journal.

Abstract
Post-exertional malaise is a cardinal symptom of myalgic encephalomyelitis and chronic fatigue syndrome. There are two differing focuses when defining post-exertional malaise: a generalized, full-body fatigue and a muscle-specific fatigue. This study aimed to discern whether post-exertional malaise is a unified construct or whether it is composed of two smaller constructs, muscle fatigue and generalized fatigue. An exploratory factor analysis was conducted on several symptoms that assess post-exertional malaise. The results suggest that post-exertional malaise is composed of two empirically different experiences, one for generalized fatigue and one for muscle-specific fatigue.

Paywalled at https://journals.sagepub.com/doi/full/10.1177/1359105316664139

 

[John Mac]

Also 2016 on this link

https://www.ncbi.nlm.nih.gov/pubmed/27557649

 

[Barry]

This is extremely valid ...

However, many patients attempt to reduce the frequency and severity of their PEM by pacing themselves and staying within their energy limits (Jason et al., 2008). As a result, they may not be currently experiencing PEM. This, in turn, could impact the way patients respond to certain subjective questions.

My wife, I think, experiences relatively mild PEM typically, though still debilitating. But when her pacing gets messed up, either by circumstance or occasional over-enthusiasm, it hits her a lot harder. Although never as severe as some describe here. But it's true of course, a key objective of pacing for a pwME is to minimise PEM, whether you think of it in those terms or not. So quizzing people about their PEM experience already has a built-in confounding factor, because you will only get told about what actually happens to them, and not about what might happen if they managed their ME differently.

 

[pteropus]

generalised fatigue and muscular fatigue aren't the full picture. should also include separate components ofcognitive malaise (eg loss of memory, loss of language, loss of numeracy, etc), neurological malaise (autonomic nervous system chaotic, peripheral nervous system erratic), cardiovascular malaise (poorer function, more intense fluctuations etc), emotional malaise (sudden onset of weepiness anger etc), neuromuscular control, etc etc etc.

also highly relevant (as mentioned above) is how well you've been pacing (in previous days weeks months), how recently and how often & severely you've triggered malaise. and whether additional activity would change the outcome.

 

[Perrier]

generalised fatigue and muscular fatigue aren't the full picture. should also include separate components ofcognitive malaise (eg loss of memory, loss of language, loss of numeracy, etc), neurological malaise (autonomic nervous system chaotic, peripheral nervous system erratic), cardiovascular malaise (poorer function, more intense fluctuations etc), emotional malaise (sudden onset of weepiness anger etc), neuromuscular control, etc etc etc.

also highly relevant (as mentioned above) is how well you've been pacing (in previous days weeks months), how recently and how often & severely you've triggered malaise. and whether additional activity would change the outcome.

Excellent description. Folks, I cannot stand the word ‘fatigue,’ as frankly it is very different from normal fatigue. It is sick feeling, toxic feeling, nausea, weakness and on and on. That is not fatigue.

 

[Mithriel]

Excellent description. Folks, I cannot stand the word ‘fatigue,’ as frankly it is very different from normal fatigue. It is sick feeling, toxic feeling, nausea, weakness and on and on. That is not fatigue.

In the 14 years before before CFS was invented I never once told a doctor I felt fatigued. Neurological problems and the toxic feeling you describe stopped me long before I became tired. My husband took a post viral illness for about 8 months after a bad case of flu and it never crossed our minds it was the same disease I had. In the ME community the emphasis was on feeling ill especially after exercise.

After CFS, fatigue was being used to describe having ME and I felt at the time that people who were newly diagnosed were taking their doctors word for it that the toxic feeling was a type of fatigue and the distinction from being tired was lost.

Many people do start being ill from feeling profound exhaustion all the time, of course, but the subtlety and range of the disease has been shoehorned into one word which is understood by outsiders in a different way from our experience.