Trial Report Impaired Hand Grip Strength Correlates with Greater Disability and Symptom Severity in Post-COVID ME/CFS, Paffrath et al, 2024

Full title:
Impaired Hand Grip Strength Correlates with Greater Disability and Symptom Severity in Post-COVID Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

https://www.mdpi.com/2077-0383/13/7/2153

Abstract
Post-COVID syndrome (PCS) encompasses a diverse array of symptoms persisting beyond 3 months after acute SARS-CoV-2 infection, with mental as well as physical fatigue being the most frequent manifestations.

Methods: In 144 female patients with PCS, hand grip strength (HGS) parameters were assessed as an objective measure of muscle fatigue, with 78 meeting the Canadian Consensus Criteria for postinfectious myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). The severity of disability and key symptoms was evaluated using self-reported questionnaires.

Results: Patients with ME/CFS exhibited heightened overall symptom severity, including lower physical function (p < 0.001), a greater degree of disability (p < 0.001), more severe fatigue (p < 0.001), postexertional malaise (p < 0.001), and autonomic dysfunction (p = 0.004) compared to other patients with PCS. While HGS was impaired similarly in all patients with PCS and exhibited a significant correlation with physical function across the entire patient group, HGS of patients with ME/CFS uniquely demonstrated associations with key symptoms.

Conclusions: Thus, impaired HGS serves as an objective marker of physical function in patients with PCS. Only in patients meeting ME/CFS criteria is impaired HGS also associated with the severity of hallmark symptoms. This suggests a common mechanism for muscle fatigue and other symptoms in the ME/CFS subtype, distinct from that in other types of PCS.

 

ME Research UK:

Hand grip strength, a measure of muscle fatigue, has previously been explored in ME/CFS. Studies note a reduction in hand grip strength in individuals with ME/CFS compared to healthy controls, and correlation between level of impairment and symptom severity. A recent study (https://bit.ly/3UlTypq) conducted by researchers from Charité – Berlin University of Medicine extended research to individuals with long COVID. Out of 144 participants with long COVID, 78 were further diagnosed with ME/CFS based on the Canadian Consensus Criteria. Interestingly, whilst hand grip strength impairment was evident in all participants with long COVID, correlations between level of hand grip strength impairment and severity of key symptoms (post-exertional malaise, cognitive impairment, fatigue, and orthostatic intolerance) were uniquely observed in the ME/CFS cohort. The study further demonstrates the potential of hand grip strength as an objective measure for physical function in ME/CFS. Read more: https://tinyurl.com/3fkd7666

#MyalgicEncephalomyelitis #MECFS #pwME #longcovid

 

The correlation between severity of symptoms being unique to the ME group is interesting. I wonder what’s going on there.

Really good to see the underlying grip strength results reproduced. Having my HGS measured and seeing my results and wider context of the 2018 paper was a clarifying moment for me. Seeing something physical, clear, simple and measurable both reduced and more significantly clearly degrading on repeated grips meant a lot.

I’d be interested in what others think. Have they ever had this test? What are people’s thoughts on how useful it is and why isn’t it used more?

 

I've had a grip test and later tests that showed what was described as 'metabolic impairment', or, the muscles running out of energy really quickly. Having the grip test as part of a wider assessment, I was a mess after just a few squeezes - but it makes sense to me for how I felt at the time vs what I know about how my body seems to work.

For me, though, the risk with all these things is how the test results are used if not accepted as a normalised set of diagnostic tests for ME. In my case, the grip test was used to suggest I wasn't using maximal effort and part of a wider effort to suggest I was exaggerating..

 

I am not sure how useful it is to try to compare severity of symptoms between people. People are likely to rate symptoms differently, even if, if one could tell, they might seem about the same.

As @Fainbrog says, the problem is in how you interpret the findings. I think there are all sorts of ways one might do that, which makes for uncertainty of value. It might be useful as an adjunct to a symptomatic outcome measure in some trials but probably not in others. Whether the correlation with symptoms when compared between individuals is helpful I am very unsure.

 

So, only the ME/CFS subgroup demonstrated the correlation between HGS and ME/CFS symptoms, while all PCS showed similar correlation between HGS and physical functioning? I must've misread something. Even if I didn't, how does a correlation suggest a common mechanism?