Preprint: Chronic COVID-19 Syndrome and Chronic Fatigue Syndrome (ME/CFS) following the first pandemic wave in Germany.., Kedor et al, 2021

Full title: Chronic COVID-19 Syndrome and Chronic Fatigue Syndrome (ME/CFS) following the first pandemic wave in Germany: a first analysis of a prospective observational study

https://www.medrxiv.org/content/10.1101/2021.02.06.21249256v1

 

MP and scientist Karl Lauterbach shared this study on Twitter and Facebook as well. Good to see this. Hopefully it will be published in a big journal

Curious about the significance of the objective measures like Mannose-binding lectin deficiency and elevated IL-8 levels. Although this is prospective we don't know if this MBL deficiency was already present beforehand. Very interesting though.

https://twitter.com/user/status/1359096665886633984

 

Code:

https://twitter.com/TomKindlon/status/1359133918075699200

 

Disappointing that they use CFQ (it encourages its continued usage) but at least they asked about more symptoms than usual. Bit weird to ask about painful lymph nodes, rather than, say, enlarged. Mine are never painful but usually enlarged, and often tingly. It would be really important to devise the list and range of symptoms so that studies don't have to make arbitrary decisions.

The symptoms distribution suggest a much higher % that should meet the CCC. Really not sure about that:

91% of CCS had PEM, but it was determined not to count pretty much arbitrarily. Certainly as single points in time. That's always an issue given the wide variability.

 

Sounds interesting but there are some big caveats. What I would like to see is a big study that follows up on a large group of patients with a confirmed COVID-19 diagnosis of which only a small group will go on to develop long term symptoms. That would provide a representative sample of the population and a test of coronacrisis leads to an increase of ME/CFS.

This study, however, simply recruited patients who already had long-term symptoms following COVID-19. The paper writes for example:

The inclusion criteria sound a lot like ME/CFS.

It also seems that they recruited patients through the website of a log COVID Facebook group:

So there is a large risk of selection bias: we don't know how representative those 44 patients in the study where of patients who get COVID-19.

 

Not a bad start (but whose dumb idea was the CFQ?!).

This bit puzzles me though. They say all but one person in the cohort of 42 had PEM but only 19 had ME (CCC). They say themselves more people would have qualified for an ME label had they used IOM or Fukuda instead of CCC. But if all but one person really had ME-type PEM anyway, insisting on CCC seems to create an artificial division here between the Chronic Covid with ME and the Chronic Covid without ME groups. More likely those supposedly without ME were just milder cases.

But. Thing is it's not clear if the PEM definition they used was ME-type PEM. Sigh. Why do researchers insist on being so vague with their reporting of PEM? Saying it lasted more than 14 hours is neither here nor there. What were the symptoms, was increased fatigue and breathlessness enough to qualify as PEM? When did it start, with a delay or not? What did they look at here, ordinary exertion intolerance or ME-PEM? How are we supposed to know?

This isn't to say people without PEM but whose symptoms otherwise look similar to ME or people with ordinary exertion intolerance shouldn't be studied. In fact it's a good idea to study them - to compare with ME-PEM and to see what similarities and/or differences there are. Just... pleeeease describe who or what you're studying and don't throw everyone into a single melting pot.

This habit has bedevilled ME for far too long and we really, really shouldn't make the same mistake all over again with long Covid.

 

It is the way they use symptoms we talk about but have no understanding of what they are. It is infuriating the number of people who say PEM but actually mean prolonged fatigue or fatigue after exercise which are common to many things.

The problems we have after exercise are different, even talking about an increase in symptoms does not mean it is PEM as people with lung damage will feel breathless but they will not get swollen glands or the other ways PEM causes symptoms not related to the exercise involved nor will they take weeks to recover

 

Yep, I think they mentioned this under Limitations of Study: