I’m sorry you are suffering with long covid Siebe. I’m personally more sceptical of the size of the effects of long covid.
One argument is a sense check—if the effects were this big, we would expect many celebrities and footballers to have retired with long covid, but I know of no such cases having looked for some time. The BBC has an article on a footballer who retired with long covid, but he wasn’t a pro footballer at the time he retired.
We’ve gotten a bit into the weeds in the other comments, and in this one I’d like to zoom out a bit to see what argument you’re actually making. I’ll make an attempt to (re)construct your argument, and you can tell me where I’m misrepresenting it.
The health burden claimed in this post is extraordinarily high, so we should see the signal even in noisy data like news reports about athletes and celebrities
We’re not seeing those reports as much as we would expect
Conclusion: something in the report is wrong
I’ve already argued against 2 with the Airtable containing >100 athlete sudden deaths/collapses + a few news articles of arguably below-top-level.
[Jan 2023 EDIT : I don’t think this Airtable is strong data anymore, but very weak]
Re: 1.
I do think that it should be taken into account that the information ecosystem around COVID and Long Covid is really, really bad. Patients typically get misdiagnosed a lot before biological abnormalities are found, public health authorities spread a lot of misinformation, and most media outlets have pretty bad coverage. In this ecosystem, I don’t think it’s easy to spot athlete retirements due to confirmed Long Covid, or any other signals.
Re: 3
More importantly, I’m of the opinion that the evidence I offer in the post is of sufficiently higher quality than a google search for news reports: i.e. cohorts with controls, population samples, disability data, and biological data (e.g. seems like at least 50% of LC patients have COVID-specific markers). In my opinion, if you want to assert that the main claim in the report is wrong, you have to additionally argue that at least one of the following is wrong (If not, I think you’re only justified to claim ‘something here doesn’t make sense, but it’s not clear what’).
A. The controlled cohort studies & disability data is wrong
B. The controlled cohort studies & disability data are do not justify the high amounts in the UK population sample
C. The population sample is right, but professional athletes have significantly lower rates of Long Covid
D. The numbers are right, but a signifcant fraction are not attributable to COVID, but something else
E. Something else, or a combination of weaker versions of the above claims
I agree with you that C is unlikely.
Also, the rate would need to be substantially lower for my claim that ‘this is a major problem’ to be invalid (although you’re not explicitly claiming it’s invalid). E.g. at 60million/year, it’s still enormous. At 30million, arguably still big.
I had a quick look at the Airtable. Many of the people included do not seem to be professional athletes at the time that they died/collapsed. For example, this includes an ice hockey player at a university, someone who plays basketball in the fourth tier of the Spanish league and a former pro runner. This expands the sample so much as to make inference from the data impossible. There is a reason to focus on professional footballers in England because we know the sample size, there are a lot of them (5,000) and we should expect news about long covid-induced retirement to make it into the news.
By your estimates, 0.25% of people in the whole UK population are impaired a lot by long covid. We should therefore expect 13 of the 5,000 English pro footballers to have retired or gone on the news saying they can’t play because of long covid. I have looked into this and know of no cases of this. I know other people have looked into this after I offered them a bet and also haven’t found any.
I think the studies of long covid are wrong and that the controls are not good. The symptoms of long covid are vague, highly variable in severity, and already widely prevalent in the population (in the integers of percent).
It’s actually higher than 0.25%. More like 1 in 5 out of ~1.8% (avg. prevalence among 17-34, with shootings >3 months), so 0.36%.
Some of those will be recent though, so those we shouldn’t expect to be reported in the news even if the news was taking everyone. 30%?
Some will retire not knowing it’s actually Long Covid and state other reasons. 50%?
That leaves like 6 people, which to me is sufficiently small that it can be missed by chance (eg. no top level players have gotten severe Long Covid).
I’m also wondering if heart failure is another outcome rather than Long Covid and disability. ME/CFS is a really strange disease where people can push through a lot, and only get the bill later. It’s not that people literally can’t run.
Regarding the studies: I agree that there’s a lot to be desired regarding symptom measurement (I think we’ll see better measurement in the future). But even the vague symptom descriptions are significantly higher in PCR-confirmed covid cases, so I don’t understand your worry.
I went through the Airtable more systematically and found 7 English football players that had heart issues/collapsed on the field in 2021/2022. None were explicitly linked to covid, but only 1 had rumours of an underlying condition. 2 out of 7 players were in League 7 though. I think it’s still pro, not sure.
I’ve considered checking samples of public figures, but dismissed it because it’s really hard to get a good sense of who has Long Covid:
not everyone knows they have Long Covid
people don’t like to say they have it. I expect this to be especially the case for professional athletes whose career depends on it
I’m not sure how much top performance is affected in mild cases. I think in early stages it’s possible to push through a lot. The main symptom is fatigue post exertion. We would still expect to observe reduced performance though, but that’s harder to observe.
Retirement is a drastic decision and people would generally postpone that.
Due to these issues, I feel like disability data is a much more reliable sense check, and I think it fits the ONS UK numbers.
The article you link to isn’t good, because they probably had a lot of Long Covid cases in their control group. They used antibodies as sole diagnostic criterion of prior infection. But about 1 in 3 people do not create detectable amounts of antibodies (https://wwwnc.cdc.gov/eid/article/27/9/21-1042_article), antibodies fade over time, and there’s some rumors that Long Covid patients are now likely to not have antibodies but I haven’t checked that. The fact that there’s no easily accessible diagnostic tool makes it hard for all these prevalence studies.
On the study, even if the antibody test isn’t that accurate, one would still expect people with confirmed covid to have more long covid symptoms than people without confirmed covid. In fact, the study finds that belief in having had covid is a stronger predictor than confirmed covid, which suggests that the symptoms are caused by something else.
But people who have had COVID do have more Long Covid, if actually use an accurate measure (PCR testing). I report multiple studies in the post with control groups.
In the study, people with positive serology HAD more of 10 specific symptoms, even though serology is very inaccurate. Only when controlled for belief did that disappear. But belief in having had COVID has strong confounding effects:
if you have lasting effects, of course you’re more likely to identify a prior infection
if you had more clear acute symptoms, you’re more likely to have both belief you’ve had COVID, as well as that you’re more likely to develop Long Covid
they say that belief and serology were not correlated, but I’m confused by that. In the belief+ group, half had positive serology. In the belief- group, it’s like 2%?
If you control a weak predictor by a strong predictor correlated with the weak predictor, I’m not surprised that significant effects disappear.
The study also had data on PCR testing but didn’t use that in any way, which seems suspicious to me.
Also, in 2020 the base rate for other communicable diseases dropped a lot (flu dropped by factor 50x)
The problem with PCR test controls is that they would only catch an infection around the time you get infected, whereas antibody tests would catch infections further back in time.
I don’t see the evidence that belief in having had covid is a better predictor of having had covid than is a serology test.
On the economist article, the study didn’t find a significant drop, it found a reduction in minutes played of 2 minutes per game and a reduction in passes of 3 per 90 minutes 225 days post-covid. Although zero effect is outside of the confidence interval for the passes metric (but not minutes played) according to the study, the effect is so small, and the measure so noisy, that in my view it is almost certainly a statistical artefact.
I agree the number of soccer players reported to be out of play due to Long Covid is low enough so we can be confident that Long Covid risk for healthy young demographics is <<2%. I’m not sure it’s low enough to be confident it’s <0.5%.* I think “0.5% Long Covid risk for young people; higher for older people” would just about make it into the lower end of Siebe’s 70% confidence interval of people who are suffering from Long Covid. (To get to the higher end of the confidence interval, we’d have to assume that the vast majority of people who get Long Covid are from older demographics and presumably had severe disease – and maybe vaccinations have brought these risks down a bunch, so I’m skeptical about the higher parts of the range in the confidence interval.)
*Professional athletes are probably trying to avoid getting Covid. After 5 minutes of googling, I could find a bunch of accounts of soccer players with Long Covid. Arguably, there are fewer than 200 “world-famous soccer players” currently active, so not seeing a case in the news of a famous player who was forced to retire isn’t strong evidence against a Long Covid incidence of 0.5%.
I don’t think pro athletes are any less likely to get covid than other people. The English football leagues continued throughout the early peaks of covid and (anecdotally) vaccine scepticism rates among footballers seem to be surprisingly high.
If any English footballer retired due to long covid, it would be national news. The premier league is by far the most popular sports league in the world and if any player retired due to long covid it would be huge news. The second tier of English football has the third highest attendances of any league in Europe; numerous clubs gets tens of thousands of fans at each game. The only case of news reporting on a footballer retiring with long covid was a BBC report report on one non-famous squad player for AFC Wimbledon (a fourth tier club with few fans) who retired because of long covid. But he had been released from his pro contract before getting covid and so wasn’t actually a pro footballer. There are about 5,000 pro footballers in England and there are no other news stories about players retiring with long covid after 1.5 years of covid. This suggests that the risk to healthy young people is low.
There are reports in the news of players suffering with long covid, where this is struggling with recovery a couple of months after getting covid, but all of those people have subsequently started playing again.
don’t really get why this has been downvoted so much. The BBC reported on a non-famous non-pro footballer player who claimed to retire due to long covid, which is evidence that the media would report on one of the 5,000 other pro footballers if they were to retire due to long covid
A lot of these aren’t directly getting attributed to COVID, but it’s highly suspicious to have medically unexplained symptoms during a pandemic. Personally, I feel like this passes your sense check ;)
On Aguero (one of the greatest strikers of all time), he retired with cardiac arrhythmia.
This article quotes his doctor: “But Roberto Peidro, who has treated Aguero since 2004, says it has “nothing to do with Covid or the Covid vaccine”.
There are cases of footballers/athletes retiring/dying with heart problems or suffering from severe heart problems every few years. The examples of Cristian Erikson, Fabrice Muamba, and Marc Vivian Foe spring to mind from memory. There is also James Taylor, the cricketer.
That’s a useful article. Makes it much less likely to be COVID related, because there’s a plausible alternative explanation (but his doctor could be wrong. Doctors have been wrong about Long Covid a lot).
I found the Air table list surprisingly big, and would love to see a year by year comparison.
I’m sorry you are suffering with long covid Siebe. I’m personally more sceptical of the size of the effects of long covid.
One argument is a sense check—if the effects were this big, we would expect many celebrities and footballers to have retired with long covid, but I know of no such cases having looked for some time. The BBC has an article on a footballer who retired with long covid, but he wasn’t a pro footballer at the time he retired.
There’s also this paper which sheds some light on the overall background rate of long covid symptoms—https://jamanetwork.com/journals/jama/article-abstract/2787741
We’ve gotten a bit into the weeds in the other comments, and in this one I’d like to zoom out a bit to see what argument you’re actually making. I’ll make an attempt to (re)construct your argument, and you can tell me where I’m misrepresenting it.
The health burden claimed in this post is extraordinarily high, so we should see the signal even in noisy data like news reports about athletes and celebrities
We’re not seeing those reports as much as we would expect
Conclusion: something in the report is wrong
I’ve already argued against 2 with the Airtable containing >100 athlete sudden deaths/collapses + a few news articles of arguably below-top-level.
[Jan 2023 EDIT : I don’t think this Airtable is strong data anymore, but very weak]
Re: 1.
I do think that it should be taken into account that the information ecosystem around COVID and Long Covid is really, really bad. Patients typically get misdiagnosed a lot before biological abnormalities are found, public health authorities spread a lot of misinformation, and most media outlets have pretty bad coverage. In this ecosystem, I don’t think it’s easy to spot athlete retirements due to confirmed Long Covid, or any other signals.
Re: 3
More importantly, I’m of the opinion that the evidence I offer in the post is of sufficiently higher quality than a google search for news reports: i.e. cohorts with controls, population samples, disability data, and biological data (e.g. seems like at least 50% of LC patients have COVID-specific markers). In my opinion, if you want to assert that the main claim in the report is wrong, you have to additionally argue that at least one of the following is wrong (If not, I think you’re only justified to claim ‘something here doesn’t make sense, but it’s not clear what’).
A. The controlled cohort studies & disability data is wrong
B. The controlled cohort studies & disability data are do not justify the high amounts in the UK population sample
C. The population sample is right, but professional athletes have significantly lower rates of Long Covid
D. The numbers are right, but a signifcant fraction are not attributable to COVID, but something else
E. Something else, or a combination of weaker versions of the above claims
I agree with you that C is unlikely.
Also, the rate would need to be substantially lower for my claim that ‘this is a major problem’ to be invalid (although you’re not explicitly claiming it’s invalid). E.g. at 60million/year, it’s still enormous. At 30million, arguably still big.
I had a quick look at the Airtable. Many of the people included do not seem to be professional athletes at the time that they died/collapsed. For example, this includes an ice hockey player at a university, someone who plays basketball in the fourth tier of the Spanish league and a former pro runner. This expands the sample so much as to make inference from the data impossible. There is a reason to focus on professional footballers in England because we know the sample size, there are a lot of them (5,000) and we should expect news about long covid-induced retirement to make it into the news.
By your estimates, 0.25% of people in the whole UK population are impaired a lot by long covid. We should therefore expect 13 of the 5,000 English pro footballers to have retired or gone on the news saying they can’t play because of long covid. I have looked into this and know of no cases of this. I know other people have looked into this after I offered them a bet and also haven’t found any.
I think the studies of long covid are wrong and that the controls are not good. The symptoms of long covid are vague, highly variable in severity, and already widely prevalent in the population (in the integers of percent).
Thanks for the clarity John!
It’s actually higher than 0.25%. More like 1 in 5 out of ~1.8% (avg. prevalence among 17-34, with shootings >3 months), so 0.36%.
Some of those will be recent though, so those we shouldn’t expect to be reported in the news even if the news was taking everyone. 30%?
Some will retire not knowing it’s actually Long Covid and state other reasons. 50%?
That leaves like 6 people, which to me is sufficiently small that it can be missed by chance (eg. no top level players have gotten severe Long Covid).
I’m also wondering if heart failure is another outcome rather than Long Covid and disability. ME/CFS is a really strange disease where people can push through a lot, and only get the bill later. It’s not that people literally can’t run.
Regarding the studies: I agree that there’s a lot to be desired regarding symptom measurement (I think we’ll see better measurement in the future). But even the vague symptom descriptions are significantly higher in PCR-confirmed covid cases, so I don’t understand your worry.
I went through the Airtable more systematically and found 7 English football players that had heart issues/collapsed on the field in 2021/2022. None were explicitly linked to covid, but only 1 had rumours of an underlying condition. 2 out of 7 players were in League 7 though. I think it’s still pro, not sure.
Analysis here.
Hi John,
I’ve considered checking samples of public figures, but dismissed it because it’s really hard to get a good sense of who has Long Covid:
not everyone knows they have Long Covid
people don’t like to say they have it. I expect this to be especially the case for professional athletes whose career depends on it
I’m not sure how much top performance is affected in mild cases. I think in early stages it’s possible to push through a lot. The main symptom is fatigue post exertion. We would still expect to observe reduced performance though, but that’s harder to observe.
Retirement is a drastic decision and people would generally postpone that.
Due to these issues, I feel like disability data is a much more reliable sense check, and I think it fits the ONS UK numbers.
The article you link to isn’t good, because they probably had a lot of Long Covid cases in their control group. They used antibodies as sole diagnostic criterion of prior infection. But about 1 in 3 people do not create detectable amounts of antibodies (https://wwwnc.cdc.gov/eid/article/27/9/21-1042_article), antibodies fade over time, and there’s some rumors that Long Covid patients are now likely to not have antibodies but I haven’t checked that. The fact that there’s no easily accessible diagnostic tool makes it hard for all these prevalence studies.
On the study, even if the antibody test isn’t that accurate, one would still expect people with confirmed covid to have more long covid symptoms than people without confirmed covid. In fact, the study finds that belief in having had covid is a stronger predictor than confirmed covid, which suggests that the symptoms are caused by something else.
But people who have had COVID do have more Long Covid, if actually use an accurate measure (PCR testing). I report multiple studies in the post with control groups.
In the study, people with positive serology HAD more of 10 specific symptoms, even though serology is very inaccurate. Only when controlled for belief did that disappear. But belief in having had COVID has strong confounding effects:
if you have lasting effects, of course you’re more likely to identify a prior infection
if you had more clear acute symptoms, you’re more likely to have both belief you’ve had COVID, as well as that you’re more likely to develop Long Covid
they say that belief and serology were not correlated, but I’m confused by that. In the belief+ group, half had positive serology. In the belief- group, it’s like 2%?
If you control a weak predictor by a strong predictor correlated with the weak predictor, I’m not surprised that significant effects disappear.
The study also had data on PCR testing but didn’t use that in any way, which seems suspicious to me.
Also, in 2020 the base rate for other communicable diseases dropped a lot (flu dropped by factor 50x)
The problem with PCR test controls is that they would only catch an infection around the time you get infected, whereas antibody tests would catch infections further back in time.
I don’t see the evidence that belief in having had covid is a better predictor of having had covid than is a serology test.
And here’s an Economist article analysing footballer performance after COVID infection: https://archive.ph/qGWKs
Average performance measures definitely dropped significantly long-term. But it doesn’t have data on all-out disability.
And this article lists a few names, but also mentions what you write: that surprisingly few athletes had Long Covid at the time of writing: https://www.washingtonpost.com/sports/2021/04/19/athletes-long-haul-covid-justin-foster/
On the economist article, the study didn’t find a significant drop, it found a reduction in minutes played of 2 minutes per game and a reduction in passes of 3 per 90 minutes 225 days post-covid. Although zero effect is outside of the confidence interval for the passes metric (but not minutes played) according to the study, the effect is so small, and the measure so noisy, that in my view it is almost certainly a statistical artefact.
Fair enough re: significance and effect size. I don’t think it’s an artefact though
Regarding public samples, I had been thinking of a political body like a parliament, but as this Senator with Long Covid says: many people are not public about their disability. https://twitter.com/wsbgnl/status/1505814009722798081?s=20&t=iLBZn1qk_BUJQcJx8kIQEg
(Not clear from the quote whether he refers to other senators, or colleagues in different positions)
I agree the number of soccer players reported to be out of play due to Long Covid is low enough so we can be confident that Long Covid risk for healthy young demographics is <<2%. I’m not sure it’s low enough to be confident it’s <0.5%.* I think “0.5% Long Covid risk for young people; higher for older people” would just about make it into the lower end of Siebe’s 70% confidence interval of people who are suffering from Long Covid. (To get to the higher end of the confidence interval, we’d have to assume that the vast majority of people who get Long Covid are from older demographics and presumably had severe disease – and maybe vaccinations have brought these risks down a bunch, so I’m skeptical about the higher parts of the range in the confidence interval.)
*Professional athletes are probably trying to avoid getting Covid. After 5 minutes of googling, I could find a bunch of accounts of soccer players with Long Covid. Arguably, there are fewer than 200 “world-famous soccer players” currently active, so not seeing a case in the news of a famous player who was forced to retire isn’t strong evidence against a Long Covid incidence of 0.5%.
Here’s the long Covid prevalence per age group per the ONS UK data, per May 1st 2022
2 to 11 0.45%
12 to 16 1.44%
17 to 24 1.50%
25 to 34 2.14%
35 to 49 3.23%
50 to 69 3.10%
70+ 1.53%
Average 2.21%
I don’t think pro athletes are any less likely to get covid than other people. The English football leagues continued throughout the early peaks of covid and (anecdotally) vaccine scepticism rates among footballers seem to be surprisingly high.
If any English footballer retired due to long covid, it would be national news. The premier league is by far the most popular sports league in the world and if any player retired due to long covid it would be huge news. The second tier of English football has the third highest attendances of any league in Europe; numerous clubs gets tens of thousands of fans at each game. The only case of news reporting on a footballer retiring with long covid was a BBC report report on one non-famous squad player for AFC Wimbledon (a fourth tier club with few fans) who retired because of long covid. But he had been released from his pro contract before getting covid and so wasn’t actually a pro footballer. There are about 5,000 pro footballers in England and there are no other news stories about players retiring with long covid after 1.5 years of covid. This suggests that the risk to healthy young people is low.
There are reports in the news of players suffering with long covid, where this is struggling with recovery a couple of months after getting covid, but all of those people have subsequently started playing again.
don’t really get why this has been downvoted so much. The BBC reported on a non-famous non-pro footballer player who claimed to retire due to long covid, which is evidence that the media would report on one of the 5,000 other pro footballers if they were to retire due to long covid
(wasn’t me!)
Okay so a person on the org’s team sent me the following:
Extensive Air table of ‘heart issues’ in athletes, 2021-2022: https://airtable.com/shrbaT4x8LG8EbvVG/tbl7xKsSUIOPAa7Mx
He also sent these news articles:
Sergio Agüero quit (striker Barca): https://www.sportingnews.com/us/amp/soccer/news/sergio-aguero-retired-heart-doesnt-work-man-city-barcelona/o6ikz9xb9h466zxdtzbdagg6
Scottish #1 female tennis player (supposedly recovered after 18 months): https://news.stv.tv/sport/scottish-number-one-tennis-player-maia-lumsden-feared-career-was-over-after-long-covid-diagnosis
2 British female tennis players (don’t know their rank) 1 supposedly recovered after 18 months, 1 bedbound: https://www.skysports.com/tennis/news/12110/12577541/british-tennis-duo-maia-lumsden-and-tanysha-dissanayake-fear-for-careers-due-to-long-covid
A lot of these aren’t directly getting attributed to COVID, but it’s highly suspicious to have medically unexplained symptoms during a pandemic. Personally, I feel like this passes your sense check ;)
On Aguero (one of the greatest strikers of all time), he retired with cardiac arrhythmia.
This article quotes his doctor: “But Roberto Peidro, who has treated Aguero since 2004, says it has “nothing to do with Covid or the Covid vaccine”.
There are cases of footballers/athletes retiring/dying with heart problems or suffering from severe heart problems every few years. The examples of Cristian Erikson, Fabrice Muamba, and Marc Vivian Foe spring to mind from memory. There is also James Taylor, the cricketer.
That’s a useful article. Makes it much less likely to be COVID related, because there’s a plausible alternative explanation (but his doctor could be wrong. Doctors have been wrong about Long Covid a lot).
I found the Air table list surprisingly big, and would love to see a year by year comparison.