• Welcome to Phoenix Rising!

    Created in 2008, Phoenix Rising is the largest and oldest forum dedicated to furthering the understanding of and finding treatments for complex chronic illnesses such as chronic fatigue syndrome (ME/CFS), fibromyalgia (FM), long COVID, postural orthostatic tachycardia syndrome (POTS), mast cell activation syndrome (MCAS), and allied diseases.

    To become a member, simply click the Register button at the top right.

Can recovery of peripheral muscle function predict cognitive task performance in CFS +/or minus FMS

Dolphin

Senior Member
Messages
17,567
Can recovery of peripheral muscle function predict cognitive task performance in chronic fatigue syndrome with and without fibromyalgia?

Phys Ther. 2014 Apr;94(4):511-22. doi: 10.2522/ptj.20130367. Epub 2013 Dec 20.

Ickmans K1, Meeus M, De Kooning M, Lambrecht L, Pattyn N, Nijs J.

Author information

Abstract

BACKGROUND:

Both good physical and cognitive functioning have a positive influence on the execution of activities of daily living.

Patients with chronic fatigue syndrome (CFS) as well as patients with fibromyalgia have marked cognitive deficits.

Furthermore, a good physical and functional health status may have a positive impact on a variety of cognitive skills-a link that has been observed in young and old individuals who are healthy, although evidence is limited in patients with CFS.

OBJECTIVE:

The purpose of this study was to examine whether recovery of upper limb muscle function could be a significant predictor of cognitive performance in patients with CFS and in patients with CFS and comorbid fibromyalgia.

Furthermore, this study determined whether cognitive performance is different between these patient groups.

DESIGN:

A case-control design was used.

METHODS:

Seventy-eight participants were included in the study: 18 patients with CFS only (CFS group), 30 patients with CFS and comorbid fibromyalgia (CFS+FM group), and 30 individuals who were healthy and inactive (control group) were studied.

Participants first completed 3 performance-based cognitive tests designed to assess selective and sustained attention, cognitive inhibition, and working memory capacity.

Seven days later, they performed a fatiguing upper limb exercise test, with subsequent recovery measures.

RESULTS:

Recovery of upper limb muscle function was found to be a significant predictor of cognitive performance in patients with CFS.

Participants in the CFS+FM group but not those in the CFS group showed significantly decreased cognitive performance compared with the control group.

LIMITATIONS:

The cross-sectional nature of this study does not allow for inferences of causation.

CONCLUSIONS:

The results suggest that better physical health status could predict better mental health in patients with CFS.
Furthermore, they underline disease heterogeneity, suggesting that reducing this factor in future research is important to better understand and uncover mechanisms regarding the nature of diverse impairments in these patients.

PMID: 24363336 [PubMed - in process]
 

Dolphin

Senior Member
Messages
17,567
From the conclusions:
The results suggest that better physical health status could predict better mental health in patients with CFS.

They spend quite a lot of the paper talking about this at various times.

However, if they wanted to test physical health status, I think they should have used a different measure e.g. results of an exercise test.

What they tested was recovery from an exercise test, something which has found to be impaired in CFS.

The study itself found:
No significant correlations between recovery capacity of upper limb muscle function and cognitive performance were found in the control group (P.05).
which would suggest that the correlation is unusual.

The participants in the control group had to be inactive because patients with CFS are known to have a more sedentary lifestyle. In this way, observed differences between groups could not be due to a higher activity level of the control group.
which suggests the results can't simply be explained by sedentary lifestyle and the like.

They only briefly mention the other interpretation of the data:
However, we do not exclude the possibility that other mechanisms also are involved and that different biological mechanisms underlie exercise, physical status, and cognitive function in patients with CFS, with and without comorbidities such as fibromyalgia.
i.e. that whatever causes the severity of the illness/disease could explain the correlation.
One would think this possibility would be highlighted more when analysing the data from a study on particular conditions.
 

Dolphin

Senior Member
Messages
17,567
I forgot to say they used the 2010 Fibromyalgia criteria:

Wolfe F, Clauw DJ, Fitzcharles MA, Goldenberg DL, Katz RS, Mease P, et al. The American College of Rheumatology preliminary diagnostic criteria for fibromyalgia and measurement of symptom severity. Arthritis Care Res (Hoboken) 2010;62:600–10. Free full text: http://onlinelibrary.wiley.com/doi/10.1002/acr.20140/full

These criteria don't require the tender point assessment and are broader. A higher percentage of CFS patients would satisfy these FMS criteria than the Wolfe et al. (1990) FMS criteria that require 11 of 18 tender points, etc.
 
Last edited: