Is Long Covid a type of ME/CFS?

[Trish]

Most people who have long Covid do get better from the ME like symptoms in the same time maybe quicker than most people with ME recover from ME in the early years.

I don't think we have evidence to support that. For example, most people who get ME like symptoms following glandular fever recover within a year, from my memory of Leonard Jason's research. Most of the early recoverers probably never get an ME diagnosis, even if they fit ME/CFS diagnostic criteria.

 

[poetinsf]

Hi,

As far as the terminology used in many studies and guidelines, I’ve noticed that subsets of Long Covid patients are often described as “fitting the diagnostic criteria of ME/CFS” or “having symptoms identical to ME/CFS” but it is rare that they are described as “having ME/CFS”.

Why is this?

My suspicion has been that there still is some doubt about ME/CFS being real. So, instead of focusing on post-viral fatigue syndrome, they created PASC with any left-over symptoms from COVID, with fatigue and PEM only as a part. Describing it as "fitting the diagnostic criteria of ME/CFS" rather than "having ME/CFS" fits the pattern. Likewise RECOVER initiative wanted to start with "clean slate", as if what was on the slate was not believable, and then went on to waste $1b doing all kinds of repetitive observational studies. (edit: grammatic)

 

[Ash]

I don't think we have evidence to support that. For example, most people who get ME like symptoms following glandular fever recover within a year, from my memory of Leonard Jason's research. Most of the early recoverers probably never get an ME diagnosis, even if they fit ME/CFS diagnostic criteria.

No you’re right if you mean people getting the optimal stringent diagnosis, but I guess I’m thinking about the what feels like far too many people who were given CFS diagnosis or in some cases ME who had all the symptoms of ME used to get post viral EBV or something maybe sliding into ME or CFS who got better enough to live normal lives after a bout in childhood adolescence or early adulthood, I know of lots of people in that situation. Whether they managed to say well or not I don’t know I’d have lost track of them. But that could be equivalent to LC because we’re not that long into that so we don’t know if people will stay well.

Also depends upon whether people get a long Covid diagnosis or not or how early they get one. So if they get one early then could just be the virus being extremely dangerous and long lasting as it is and not a thing like ME at all.

You have to be diagnosed with long Covid early because all the other freaks are getting well in five days apparently and we’re in an economic hellscape so that’s the only way people can get time off work and rest. Ideally you’d be diagnosing everyone in three weeks so you could whisk them off for a battery of tests, but that’s not happening.

I am not in favour of diagnosing ME early because there are plenty of other vicious viruses out there which just are gonna take months maybe 18, to recover from and it’s better to acknowledge this biological reality rather than trying to pretend that humans are over all the viruses that don’t immediately kill them in a few weeks. But I am in favour of early diagnosis with some kind of post infectious syndrome and also loads of testing to get data for human health. I guess if we get genetic findings that are strong for ME somewhere, then everyone who has any kind is virus longer than a month could get tested to if they’re one of the lucky high risk ones. But any finding from any study that means we can be sure people have ME or are likely higher risk then the earlier the detection the better probably. But I don’t know in our economic system as it’s going that probably won’t be knowledge that’s as protective as it once was, everyone will be forced to work no matter how sick because Covid has normalised mass sickness and we were heading that way politically anyway.

In a case for any patient with ME or LC and PEM they have to have an early diagnosis to stop people recommending exercise as the best recovery plan but people are very much so recommending it anyway so a bit of way to go on that one.

My fear with early diagnosis as well as unrealistically high recovery rates being taken from people diagnosed possibly too early is the reality that doctors do/will stop looking for alternative diagnosis as do patients usually at least for a little while. Also then even for new symptoms you can’t get investigations, so it’s not a safe haven.

 

[Kitty]

I am not in favour of diagnosing ME early because there are plenty of other vicious viruses out there which just are gonna take months maybe 18, to recover from and it’s better to acknowledge this biological reality rather than trying to pretend that humans are over all the viruses that don’t immediately kill them in a few weeks. But I am in favour of early diagnosis with some kind of post infectious syndrome and also loads of testing to get data for human health.

I'm not sure. It seems to be accepted that natural recovery is possible in ME, and we really need to know what proportion does recover and how long it takes.

It wouldn't be possible to separate new onset ME from other post-infectious conditions anyway, because they'd look just the same. The only one that's feasible at the moment is if onset follows a known Covid infection.

If someone has the symptoms of ME they should be diagnosed with it, so that they know how to manage it and doctors can gather much-needed information about the natural history. Only when we have a much better picture can we think about whether or not there's a useful distinction between post-infectious syndromes that resolve within a couple of years, and those that don't.

 

[Ash]

I'm not sure. It seems to be accepted that natural recovery is possible in ME, and we really need to know what proportion does recover and how long it takes.

It wouldn't be possible to separate new onset ME from other post-infectious conditions anyway, because they'd look just the same. The only one that's feasible at the moment is if onset follows a known Covid infection.

If someone has the symptoms of ME they should be diagnosed with it, so that they know how to manage it and doctors can gather much-needed information about the natural history. Only when we have a much better picture can we think about whether or not there's a useful distinction between post-infectious syndromes that resolve within a couple of years, and those that don't.

It’s not that I don’t think people recover from ME. It’s that I think a lot of people have their life ruined by being put on the ME scrapheap, I am all in favour of an intermediate diagnosis, suspect ME or whatever and I’d be fine with ME straight up too, if doctors were on average capable of changing their minds or not viewing ME as specifically a sign that nothing serious can possibly forevermore be wrong with you. But they’re demonstrably not capable of this.

Sure some ME patients scattered about get an ME diagnosis and good medical treatment but most don’t. For example I personally have had no less than three very common treatable lifelong conditions diagnosed years and decades late simply because the doctor slammed shut the door to investigations with the ME diagnosis.

Now that wasn’t actually the case when it was still post viral whatever, they warned me it might be ME they certainly didn’t give me all the investigations that I needed, but they did consider various options and test me for stuff. ME is like a steel trap and that wouldn’t be a bad thing if you couldn’t get out but you could add to it but the symptoms are so broad and similar to many other illnesses that that rules out a lot of other causes say, in my experience every other illness that includes fatigue, because ‘I’m not concerned. We do know that fits ‘chronic fatigue’. I know people with ME who get better medical care that me but they’re mild and can deal with going to the doctors a million times until they break them down with their relentlessness but it still makes them miserable and low having to do this. My own all time low was being refused px for a cream for a small patch of contact dermatitis (plant sap original cause I think) that wasn’t healing properly on ground that that was my “CFS” and when they told me my lifelong asthma wasn’t likely causing me my asthma symptoms that would be my CFS too. ME just sends them wild, totally out of control.

I mean I get that it’s good for us as a category to study and such to nail down diagnosis quicker and it’s bound to be good to get quicker diagnosis when there are bio markers or something like that. But right now I still think it’s a very risky diagnosis to aquire for individual involved, because once you do times up for looking at the alternatives.

Still maybe ‘ME FND’(as they like to conceive of it) is still an improvement on straight FND and from that point of view it could be a help to get in there quick as possible.


But also I don’t think it’s a good idea to promote the idea that viruses don’t or can’t have long lasting consequences unless you have ME or some other disease, because viral infections are a disease all by themselves(well all in your body) and these can take a very long time to recover from.

I’m sure it’ll turn out that people with certain genetic makeup and certain environmental challenges will be more likely to suffer a longer time with viruses. Like people with ME. But we know that that applies to other diseases also.

 

[Sean]

It seems to be accepted that natural recovery is possible in ME

It is not clear at all to me if 'recovered' patients are actually fully recovered in the conventional sense, or if the degree of underlying pathology has reduced to a level that is no longer a practical issue to them, and they – quite understandably – want to put as much distance between them and the experience as possible, so they say they are recovered.

I suspect that when we get some good tests for ME/CFS we will find that those patients still have limitations, but the underlying pathological mechanisms have dampened right down, for whatever reasons, but not disappeared.

 

[poetinsf]

It is not clear at all to me if 'recovered' patients are actually fully recovered in the conventional sense, or if the degree of underlying pathology has reduced to a level that is no longer a practical issue to them, and they – quite understandably – want to put as much distance between them and the experience as possible, so they say they are recovered.

Or, they could be claiming that they recovered because they don't want to have ME/CFS trivialized. Imagine what people not well versed with ME/CFS would say looking at you who can bike or hike a decent distance, and yet complain about the ME/CFS limitation.

I suspect that when we get some good tests for ME/CFS we will find that those patients still have limitations, but the underlying pathological mechanisms have dampened right down, for whatever reasons, but not disappeared.

Having gone through just about the whole spectrum of ME/CFS, my view is that even the healthy people suffer from PEM at times. People crashing the day after a stressful work is over or going into a funk after a long thru-hike is strikingly similar to what I see in recovered patients with limitation, at lesser distance/intensity. If that is the case, then the test may not be binary. It may only tell you a value and whether you are within the acceptable range, like your cholesterol level.

(Edits for clarification)

 

[Ash]

Or, they could be claiming that they recovered because they don't want to have ME/CFS trivialized. Imagine what people not well versed with ME/CFS would say looking at you who can bike or hike a decent distance, and yet complain about the ME/CFS limitation.


Having gone through just about the whole spectrum of ME/CFS, my view is that even the healthy people suffer from PEM at times. People crashing the day after a stressful work is over or going into a funk after a long thru-hike is strikingly similar to what I see in recovered patients with limitation, at lesser distance/intensity. If that is the case, then the test may not be binary. It may only tell you a value and whether you are within the acceptable range, like your cholesterol level.

(Edits for clarification)

I can imagine a non definitive test.

I don’t think healthy people get PEM. Because what you’re describing is people damaging their body through overexertion and deprivation of sleep and rest. That will take time to heal from.

PEM is an abnormally easy to provoke state of sickness following minimal or ordinary activity physical or mental or exposure to normal sensory stimulus.

 

[forestglip]

I can imagine a non definitive test.

I don’t think healthy people get PEM. Because what you’re describing is people damaging their body through overexertion and deprivation of sleep and rest. That will take time to heal from.

PEM is an abnormally easy to provoke state of sickness following minimal or ordinary activity physical or mental or exposure to normal sensory stimulus.

I think I'd agree with @poetsinf that it's probably a spectrum going all the way from severe PEM to healthy people having a "healthy" level of PEM.

"damaging their body through overexertion" - whatever the reason, it looks similar, so it's possibly the same mechanism, just exaggerated. Maybe in pwME, the threshhold before exertion starts damaging the body is just far lower for some reason, so the PEM consequently is a lot more obvious and strange compared to normal people.

I have a theory that introverts, or people who feel that they need to recharge after social interaction, are potentially exhibiting PEM caused by mental+emotional exertion, through a similar mechanism to ME/CFS.

 

[Kitty]

I have a theory that introverts, or people who feel that they need to recharge after social interaction, are potentially exhibiting PEM caused by mental+emotional exertion, through a similar mechanism to ME/CFS.

As an autistic introvert from a family of introverts, I can happily confirm that it doesn't resemble PEM in any way. Not even a homeopathic-strength hint of it.

For start, it's not obligatory (we'd rather have time to recharge, but can manage without) and going to work every day in a highly social industry never had an accumulating or compounding effect. Those two phenomena are defining aspects of PEM.

 

[forestglip]

As an autistic introvert from a family of introverts, I can happily confirm that it doesn't resemble PEM in any way. Not even a homeopathic-strength hint of it.

For start, it's notobligatory (we'd rather have time to recharge, but can manage without) and going to work every day in a highly social industry never had an accumulating or compounding effect. Those two phenomena are defining aspects of PEM.

That's interesting. As someone with pretty bad social anxiety, even before I developed clear ME/CFS, it felt like exertion to socialize, and would compound. Though I've always felt kind of like an "extrovert trapped by social anxiety". I have high motivation to be socializing, but the anxiety isn't worth it.

I've recently begun to think this, and some other symptoms, like mental fatigue making schoolwork very difficult, were mild/very mild ME/CFS my whole life, which got triggered to moderate-severe by some drugs.

Edit: So maybe not introverts, but I think it is possible that at least some subtypes of social anxiety might have a similar mechanism to ME/CFS. I know a lot of people with SA, including me, lament that one of the most annoying/disabling symptoms is something like mental fatigue in conversation, and inability to think of things to talk about, which makes things super awkward.

And one of the strongest pieces of evidence I see is that in many people with social anxiety, including me, Adderall (temporarily and usually unsustainably) completely eliminates the social anxiety. Could it be that a stimulant is helping so well because social anxiety, in at least this (large) subset of SA sufferers, is a mental fatigue issue?

Of course it could be a totally different fatigue disorder from ME/CFS, the only reason I think it might be related is that I have both, but that could be a coincidence.

This may be straying too far from the thread though, and I might start a new thread if anyone thinks it's worth it.

 

[Ash]

I think I'd agree with @poetsinf that it's probably a spectrum going all the way from severe PEM to healthy people having a "healthy" level of PEM.

"damaging their body through overexertion" - whatever the reason, it looks similar, so it's possibly the same mechanism, just exaggerated. Maybe in pwME, the threshhold before exertion starts damaging the body is just far lower for some reason, so the PEM consequently is a lot more obvious and strange compared to normal people.

I have a theory that introverts, or people who feel that they need to recharge after social interaction, are potentially exhibiting PEM caused by mental+emotional exertion, through a similar mechanism to ME/CFS.

No I think that the whole experience of PEM is the experience of being sick horribly sick and can only be had when you have a disease of some kind or maybe are being exposed to toxic substances, or complications of infections or brain injuries.


People needing rest and time to recover from activities or events or emotional distress or sensory load is normal and this applies to everyone.

If people aren’t able to rest and relax after periods of high activity and illness or injury or emotional or sensory experiences or intensive cognitive output, then they will be run down and it will take time and rest for them to recover. ‘Healthy’ people get sick too.

It’s only because we live under pressure to work too much that everyone feels tired or fatigued or sick. But it’s related to the conditions being too much for the body, not to the body lacking capacity to heal or to recover, the ‘healthy’ person would recover if they weren’t having to work three jobs or be up all night with their baby.

Most people simply can’t live in a way that would leave them feeling rested and recovered. That doesn’t mean that they have PEM it means that they are stretched too thin, because capitalism means those who narrate for our culture encourage us to both pathologise fatigue and the human need for rest in the ‘healthy’ person (work, work, work), and minimise the fatigue and pain of sickness (think it away, think it away) so as not to be called upon to care for workers or non workers alike and to flatten the landscape.

Since the Covid pandemic has been disabling people on a grand scale and everyone is sick now, but might not be able to acknowledge it for fear of losing a job or the respect of their community we probably have an awful lot of not actually ‘healthy’ people who are being counted as healthy dropping the bar on normal functioning. But I think we should reject that logic.

 

[Kitty]

As someone with pretty bad social anxiety

That probably is different to introversion, as severe anxiety can be physically exhausting. My only proper taste of it was when required to speak in front of others or similar. Every muscle seemed to be held in tension, and I'd leave feeling as if I'd done a 10-mile hike.

I get some of it playing music with others, as I've only picked it up again recently. The difference there is that I do relax when we get going—you have to, you can't play fast reels when you're tense.

 

[Mij]

I have a theory that introverts, or people who feel that they need to recharge after social interaction, are potentially exhibiting PEM caused by mental+emotional exertion, through a similar mechanism to ME/CFS.

As a social introvert I would describe this more as burnout from too much socializing.

 

[Ash]

That's interesting. As someone with pretty bad social anxiety, even before I developed clear ME/CFS, it felt like exertion to socialize, and would compound. Though I've always felt kind of like an "extrovert trapped by social anxiety". I have high motivation to be socializing, but the anxiety isn't worth it.

I've recently begun to think this, and some other symptoms, like mental fatigue making schoolwork very difficult, were mild/very mild ME/CFS my whole life, which got triggered to moderate-severe by some drugs.

Could be, kids do get this and it’s difficult to understand when you’re a kid cause you don’t have much to compare with being ill.

I think people vary enormously in what drains their energies and how quickly that might happen that they reach their limits, that is a spectrum.

Sometimes because of an internal burden a health condition or an injury, or difficulties with feelings and reactions and sometimes due to outside factors such as difficulty in the environment and the social conditions and sometimes just because people are people.

But having a lower threshold or feeling unwell if you push it too far wouldn’t necessarily be PEM even if you were chronically unwell feeling even more unwell after an activity. It could be having a lower than average threshold for what you can manage before it’s too much and not being given accommodations.

But I’d say though it can be very difficult to know if you have PEM sometimes, either when it’s mild enough to be only subtly different from simply hitting a ceiling a bit earlier than others might or when it’s so severe that you’re in it all the time.

So if you’re chronically ill you will certainly feel unwell and especially so with extra activity, and you may make yourself sicker or accelerate a deterioration from too many demands on your body. But you might or might not have this damage arriving via PEM.

I guess I mean PEM is or maybe a particular subset of limitations or dysfunctions that could happen to an over stretched or unwell body. Rather than the only one.

Although it could be that a particular common pathway to feeling bad is just super hyped in ME and is harder to notice in other illnesses. But since we are naming a specific phenomena, it’s the ridiculously over the top ness of it that makes it PEM, and a notable feature of this illness rather than how everyone is.


It will be amazing if we can find out what is actually happening in PEM one day soon huh?

 

[rvallee]

IoM has "lasts for more than 6 months" as a criterion. The new NICE ME/CFS guideline specifies "confirmed after 3 months of persistent symptoms" (s1.3.2); the previous NICE guideline, CG53, specified 4 months in an adult and 3 months in a child or young person (s1.3.1.1).

Which given the data we have from LC sounds about a good cut-off for better odds of recovery, but it's still very disruptive to be ill for 3 months. I don't agree with the idea that there is a fundamental difference between those who recover and those who don't. There is a difference, but it doesn't add up to a different condition requiring different criteria.

And given how well-established how exertion worsens outcomes in so many, diagnosis should be made as early as possible precisely to improve those odds. What matters then is follow-up, which right is just as lacking as initial diagnosis.

 

[rvallee]

It is not clear at all to me if 'recovered' patients are actually fully recovered in the conventional sense, or if the degree of underlying pathology has reduced to a level that is no longer a practical issue to them, and they – quite understandably – want to put as much distance between them and the experience as possible, so they say they are recovered.

I suspect that when we get some good tests for ME/CFS we will find that those patients still have limitations, but the underlying pathological mechanisms have dampened right down, for whatever reasons, but not disappeared.

This is common in LC. I see a lot of people who declared themselves recovered (for some time it was common for people to make posts on the LC sub-reddit about leaving because they recovered, much less nowadays) who relapsed later.

And one of the most common themes is being X% recovered, with comments that always speak of how it can radically shift one way or another with no apparent trigger. PEM is basically the most common theme overall, which I guess sort of answers the original question of the thread, although not everyone does so the whole picture is complex and fluid. ME/CFS is no longer taboo there, it's a very frequent and well-informed, far better than 99% of MDs, topic of discussion.

The most common triggers are exertion/stress, such as returning to work and exercise, but crashes that seem random (as best as they can't tell) are quite common too, sometimes weeks or months after either what was considered a recovery (although when asked there is usually a bit of remaining symptoms) or a partial remission.

Which is why follow-up is critical, even if it's just to properly record and work with accurate data. A lot of long haulers have thought themselves mostly or fully recovered and relapsed later, which frankly should put an end to all the silly LP/brain retraining pseudoscience but when professionals are the biggest peddlers of pseudoscience, we have a lot of problems to address before we get there. That none of this data is properly recorded is frankly an absurd level of negligence, it's not even hard to do. Fortunately the observational studies will capture much of it, so at least we got that going on for us.

 

[Hutan]

Useful review paper out:
The persistence of [ME/CFS] after SARS-CoV-2 infection: A systematic review and meta-analysis, 2024, Dehlia et al
Finding that 51% of people with Long Covid in the included studies meet ME/CFS criteria