Validation of the Severity of ME/CFS by Other Measures than History: Activity Bracelet, CPET, SF-36. van Campen et al, 2020

[John Mac]

Full title:
Validation of the Severity of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome by Other Measures than History: Activity Bracelet, Cardiopulmonary Exercise Testing and a Validated Activity Questionnaire: SF-36

Abstract
Introduction:
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a severe and disabling chronic disease. Grading patient’s symptom and disease severity for comparison and therapeutic decision-making is necessary. Clinical grading that depends on patient self-report is subject to inter-individual variability. Having more objective measures to grade and confirm clinical grading would be desirable.

Therefore, the aim of this study was to validate the clinical severity grading that has been proposed by the authors of the ME International Consensus Criteria (ICC) using more standardized measures like questionnaires, and objective measures such as physical activity tracking and cardiopulmonary exercise testing.

Methods and results:
The clinical database of a subspecialty ME/CFS clinic was searched for patients who had completed the SF 36 questionnaire, worn a SensewearTM armband for five days, and undergone a cardiopulmonary exercise test.
Only patients who completed all three investigations within 3 months from each other—to improve the likelihood of stable disease—were included in the analysis.

Two-hundred-eighty-nine patients were analyzed: 121 were graded as mild, 98 as moderate and 70 as having severe disease.
The mean (SD) physical activity subscale of the SF-36 was 70 (11) for mild, 43 (8) for moderate and 15 (10) for severe ME/CFS patients.
The mean (SD) number of steps per day was 8235 (1004) for mild, 5195 (1231) for moderate and 2031 (824) for severe disease.
The mean (SD) percent predicted oxygen consumption at the ventilatory threshold was 47 (11)% for mild, 38 (7)% for moderate and 30 (7)% for severe disease.
The percent peak oxygen consumption was 90 (14)% for mild, 64 (8)% for moderate and 48 (9)% for severe disease.
All comparisons were p < 0.0001.

Conclusion:
This study confirms the validity of the ICC severity grading. Grading assigned by clinicians on the basis of patient self-report created groups that differed significantly on measures of activity using the SF-36 physical function subscale and objective measures of steps per day and exercise capacity. There was variability in function within severity grading groups, so grading based on self-report can be strengthened by the use of these supplementary measures.

https://www.mdpi.com/2227-9032/8/3/273

 

[Tom Kindlon]

 

[rvallee]

Obviously the reason why actimetry was dropped in PACE and every subsequent experiment: it matches the subjective reporting when using relevant absolute (although generic) scores like the SF-36. The entire premise of the psychosocial model of ME/MUS is a mismatch in perception. Which is correct, except this mismatch exists entirely in the minds of third-party observers with no understanding of the illness. As was always obvious but, you know, eminence-based medicine of the "he said, they lied" type and all those jazz hands.

This also shows that the "mildly" ill have nearly regular activity levels, albeit sedentary and avoiding strenuous activity. Completely blows away the premise of deconditioning and fear of activity. Again. Which was always a complete BS argument and easily verifiable but psychosocial ideology is impervious to such details as... facts.

I would freely argue they understand this and knowingly buried this to avoid embarrassment. It should not have worked but this disease has been politicized to death and so here we are, the BPS brigades lied and people died. They have not repeated that mistake since, of trying to objectively measure anything. That is the only lesson learned in decades of this nonsense: do not actually measure anything.

Looking at the reviews seems to find no significant flaws. I don't find the SF-36 to be that relevant, it's too generic, but it at least more or less aligns with objective measures. The rest is fairly standard, with actimetry and maximal effort CPET.

Ironically this about in line with White's own scale of CFS being below a SF-36 of 75. Sounds about right. Too bad he's full of crap and put his name to a PACE of garbage ignoring his own definitions, willingly cheating to avoid embarrassment. Doesn't change anything, Peter, you are an embarrassment to your profession, as are all your corrupt colleagues with their blood-dripping hands.

 

[Lidia Thompson]

This is fascinating.
But could someone please explain this for me?
"The mean (SD) number of steps per day was 8235 (1004) for mild, 5195 (1231) for moderate and 2031 (824) for severe disease."

Are folk who are 'mildly affected' averaging 8235 steps per day? Is that right?
(That seems awfully high to me btw.)
What then does the number in brackets (after the step count) signify? It can't be the number of patients because ... well ... there weren't that many taking part.
Any ideas?

 

[Lidia Thompson]

... Oh I'm so very embarrassed!! This from a woman who (reportedly) has a physics degree! It's the Standard Deviation of course ... what a numpty!

 

[Trish]

This is fascinating.
But could someone please explain this for me?
"The mean (SD) number of steps per day was 8235 (1004) for mild, 5195 (1231) for moderate and 2031 (824) for severe disease."

I had the same reaction. When I classed my ME as mild and I could, with difficulty, work part time and raise a family, my SF-36 PF and steps were in the moderate ranges shown here. No way could I have walked 8,000 steps a day, and my SF-36 on an average day was about 40.

 

[rvallee]

This is fascinating.
But could someone please explain this for me?
"The mean (SD) number of steps per day was 8235 (1004) for mild, 5195 (1231) for moderate and 2031 (824) for severe disease."

Are folk who are 'mildly affected' averaging 8235 steps per day? Is that right?
(That seems awfully high to me btw.)
What then does the number in brackets (after the step count) signify? It can't be the number of patients because ... well ... there weren't that many taking part.
Any ideas?

Those steps tend to be inflated, the devices are not precise. It's only relevant in comparing the numbers from the same device, but the absolute numbers themselves are inaccurate.

I wore a Fitbit for a few months. I could clearly steps being counted despite sitting down, simply because I was moving my arms, say to drink something. I don't move my arms all that much, I wasn't doing stretching or applauding or whatever, just moving normally. So in a sense it also adds up arm movement to give a general sense of activity level, but definitely not actual steps taken.

There's also quite a difference between long rapid strides and a short shuffle. I used to walk fast everywhere. Now I shuffle around like a very old man. This distinction doesn't really translate well.

 

[hinterland]

I think this is an interesting study and valuable data, but what about patients with predominantly neurocognitive symptoms? A grading system based only on physical function will not recognise their disability.

Clearly such a grading system isn’t absolute and is only measuring one aspect of an individual’s function.

 

[Lidia Thompson]

Those steps tend to be inflated, the devices are not precise. It's only relevant in comparing the numbers from the same device, but the absolute numbers themselves are inaccurate.

There's also quite a difference between long rapid strides and a short shuffle. I used to walk fast everywhere. Now I shuffle around like a very old man. This distinction doesn't really translate well.

True. I consistently do a reasonable number of steps per day (3000-5000), but my pattern is 'potter, potter, rest ... potter, potter, rest'. The actual associated stride length for each step is very small and I avoid getting out of breath.
So when I went on a (short) walk with a friend recently, probably no longer than 15 minutes, I was genuinely shocked when I woke up (if you can call it that) the next day, absolutely whiped out. I genuinely forgot how bad things actually are. (Although how I can still forget after 30 years of this, is a mystery.) This went on for a couple of days and my subsequent number of daily steps, plummeted.

Interestingly, when I play the piano (and again, I can only do this for short periods of time) my fitbit clocks up loads of additional steps. It's helped to explain why I've largely stopped playing and why I get so ill after I do.

I would have said that I was in a 'mild' phase at the moment as I'm about as good as it gets. But from the research it would appear that I'm more likely to be 'moderate'.
Bottom line: I think I'm just used to this and have therefore developed a lot of resilience. This makes sense actually as I have had periods (in the order of years) where I have been quite severe.

Does anybody know where one can go in the UK and get one of these CPET tests? I would love to park the results under my GP's nose. It would be very therapeutic!

 

[NelliePledge]

On my worst days I can be down to 6/700 steps in a day. On better days 2-2.5k More than that would be on highly exceptional days such as when travelling.

I’ve got online food shopping and am able to drive myself if needed so I am not forced to walk for basic needs other than round my house and small garden. I’m surprised at the step numbers I would imagine many people with severe ME are barely doing any steps at all. And the numbers for mild ME are higher than what I’ve seen quoted for the average British person.

 

[Snow Leopard]

This is fascinating.
But could someone please explain this for me?
"The mean (SD) number of steps per day was 8235 (1004) for mild, 5195 (1231) for moderate and 2031 (824) for severe disease."

I had the same reaction. 8000 steps, wow! 5200 steps is around 4 km!

I could do 5000 steps maybe once a week if I were to rest for the next few days!

 

[Hoopoe]

According to this metric I estimate I would be somewhere between moderate and severe, and more towards severe. I recently measured my steps during a walk and 2700 was enough to trigger a symptom exacerbation lasting several days. That was probably also the result of similar exertion on previous days but it's still upsetting. I don't walk around much when at home. On bad days I'm probably well below 1000 steps per day.

My step counting method for the walk was to count the steps in a minute and repeating this several times. With a stopwatch I measured time spent walking. I did 1,8 steps per second when walking at brisk pace.

On the other hand I went swimming again for a long timer than this one walk and it didn't make me crash (felt dizzy and weak when coming out of the water though). Maybe it's the many pauses I had to take, or there is something about the water reducing the effect of gravity and being more horizontal that reduces the risk of PEM.

 

[adambeyoncelowe]

I think steps vary from country to country. The NHS website on exercise says the average Brit does 3-4K steps per day. American sources say 5-6K per day.

I think, if these were UK numbers, you might want to drop them by a third or so.

 

[Hell..hath..no..fury...]

On a usual day I walk between 0 and 50 steps (shuffling between rooms) and I class myself as mild to
Moderate at the moment.

when I used to wear a Fitbit it used to count me crawling along the floor at a snails pace as walking. Didn’t see the point in using it as it was too inaccurate. On a good day I use my hands a lot for leatherwork or other crafts and that was counted as walking even if I was in bed doing it.

on a good day going out, I get a taxi to the metro. Go to a place over the road from the metro destination station, and on way home usually get a taxi home after the metro. Lucky if I cover 300 steps. Walking isn’t my achievement on those days, psyching up enough brain energy to have a conversation with other humans is my achievement.

I tend to judge good and bad days based on if I have the strength to speak, if I can read one whole page of a book without brain shutting down for a few hours, if I can stay awake longer than 3 hours in a 24 hour period and stay out of a trance, rather than the amount of steps.

 

[Michelle]

So, what's the benefit of a FitBit over a good ol' fashioned pedometer? I would think pedometers would be cheaper and avoid all the arm-waving.

I've been using a pedometer clipped to my underwear for years now. While it's not perfect (urinary urgency can make me jiggle my legs a lot), it's good at getting a rough approximation of functional capacity (approx. 400 steps/day). What it was also helpful at picking up was how my gait changes depending on how I'm feeling. On better days, my step count goes up far more than expected because I actually walk rather than shuffle and on bad days when I can barely move my legs, it picks up maybe only 1 in 5 steps.

I know FitBits pick up sleep and heart rate apparently, so maybe that's the benefit? But I'd think a pedometer would be more accurate.

 

[Mithriel]

On a usual day I walk between 0 and 50 steps (shuffling between rooms) and I class myself as mild to Moderate at the moment.

I tend to judge good and bad days based on if I have the strength to speak, if I can read one whole page of a book without brain shutting down for a few hours, if I can stay awake longer than 3 hours in a 24 hour period and stay out of a trance, rather than the amount of steps.

I am not completely bedbound but after 10 years of being only mildly affected now am in the 'moderate' stage of ME/CFS. I am mostly housebound and need to lie in bed 70% of the time.

Off topic, but I think it is important. ME can become so bad it is almost unimaginable that people can exist like that and the general public and even most medics wouldn't believe you if you said it was possible to be like that with no medical intervention. But as a result people class themselves as mild but only in relation to how bad it can get.

Luna, managing 50 steps a day is severe illness. MSEsperanza, being 70% bedbound is severe illness and must be terrible to cope with.

Outsiders devalue our suffering but we must not do it to ourselves. 8000 steps a day to struggle to work and cope with life actually is mild illness. Most of us here could not manage it because I doubt if anyone without at least moderate illness is on a forum for ME.

It is easy to forget exactly what other people think mild and moderate illness means, how much life is restricted for us. If we minimise it all then no one else will take it seriously. We live in a culture where downplaying problems is the norm but we should be shouting how bad a disease this is.

 

[It's M.E. Linda]

Off topic, but I think it is important. ME can become so bad it is almost unimaginable that people can exist like that and the general public and even most medics wouldn't believe you if you said it was possible to be like that with no medical intervention. But as a result people class themselves as mild but only in relation to how bad it can get.

Luna, managing 50 steps a day is severe illness. MSEsperanza, being 70% bedbound is severe illness and must be terrible to cope with.

Outsiders devalue our suffering but we must not do it to ourselves. 8000 steps a day to struggle to work and cope with life actually is mild illness. Most of us here could not manage it because I doubt if anyone without at least moderate illness is on a forum for ME.

It is easy to forget exactly what other people think mild and moderate illness means, how much life is restricted for us. If we minimise it all then no one else will take it seriously. We live in a culture where downplaying problems is the norm but we should be shouting how bad a disease this is.

I am constantly surprised at how many friends and colleagues describe their disease as “just Moderate”.

I am not thinking well - too much stuff churning around -

I agree with @Mithriel

 

[MSEsperanza]

I think that's an important point @Mithriel and @It's M.E. Linda .

Not able to explain now in detail, but it certainly is confusing;

I'm severely ill, severely disabled ('officialy' acknowledged even incapacitated for work) , but according to the categories of how severe M.E. can get, I think am still only in the moderate category of M.E. In the 30% of time that I am not bedbound, I still can do a lot compared to others with M.E. and maybe even compared to other 'unfit' / deconditioned /sedentary but otherwise healthy people.(*)

I agree though we perhaps need different wording to describe the stages/ categories of M.E.

(*) edited: on the other hand, because of that 30% I am not sure if ME can be like that and sometimes doubt my M.E. diagnosis.

 

[Mithriel]

Yes, the scales are for ME, not for illness. Ramsay spoke about patients with ME who could work for a few weeks then collapsed again. That variability is a classic sign of ME and it is perfectly possible to be able to do quite a lot for a few hours then be collapsed for the rest.

It is part of the constant dilemma. Should I do as much as I feel I can then have to rest or if I rested all the time would I improve. (Not boom or bust, though, that is a complete distortion.)

I hope you manage to get some fun out of life!

 

[inox]

This study obviosly didn’t include patients we in the community would call severe cases.

To be included you had to - within a 3 month window :

«completed the SF 36 questionnaire, worn a SensewearTM armband for five days, and undergone a cardiopulmonary exercise test»

You don’t do exercise tests as a severe ME patient.

Once again, the true horrors of just how bad this illness can get is hidden.

I would also argue the study also could imply misuse/overuse of the diagnosis, when patient they classified as mild cases have near normal stepcounts. Don’t most of diagnosis guidlines set an loss of about half normal functioning, or similar, to use the ME diagnosis?

Anyhow, still good that studies are done to validate functional loss, and scales to objective measures. And this is a valuble reference as is.

Still, just wish scientist would communicate with patients communities, learn about the illness many faces before once again - probably without realising - once again hiding the sickest of us.