4 ms·

This sounds alarming: > There is strong evidence for brain-related pathologies in COVID-19, some of which could be a consequence of viral neurotropism. This d

This sounds alarming: > There is strong evidence for brain-related pathologies in COVID-19, some of which could be a consequence of viral neurotropism. This doesn't: > We further compared COVID-19 patients who had been hospitalised (n=15) with those who had not (n=379), and while results were not significant, we found comparatively similar findings to the COVID-19 vs control group comparison What are the quantitative findings of "loss of grey matter"? What mechanism/s are suspected that might be specific to COVID19?

dasudasu 5y ago
>Our findings thus consistently relate to loss of grey matter in limbic cortical areas directly linked to the primary olfactory and gustatory system. Looks like the loss of smell is due to an impact of the virus on brain tissue. It would be interesting to check if it ever comes back to normal months/years later.
- ljf 5y ago
  Totally anecdotal, but my wife who was very ill with both covid and then long covid, only lost her smell for a day before it returned. Another friend who had very few symptoms still has no sense of smell 9 months later - her smell can come and go, and she will also now 'miss-smell' smelling nice things as horrible and horrible as nice.
goodoldneon 5y ago
Kind of a tangent, but I get frustrated when researchers publicly release results when one of their groups have a ridiculously small sample size. It’s irresponsible to release results based on 15 people
- deleted 5y ago
  [deleted]
- Xylakant 5y ago
  The article is “published” on a preprint server and carries a suitable warning at the top. It’s preliminary, unverified and not reviewed. The target audience is other researchers, not the general public. It’s useful to publish preliminary results based on low sample sizes, it can guide future research. Basically a “hey, we found something we consider interesting, it may be worth having a better look at this.” It’s very dangerous to read too much into this, though - hence the warning at the top.
- onlyrealcuzzo 5y ago
  I thought this also - but as it turns out - you can make conclusions with really small sample sizes in medicine. For example (this has nothing to do with the paper), if the average rate of some condition - some rare brain tumor - is 1 in 50M - and you take 200 COVID-19 patients and 4 of them have it - and they have several of these tumors - you can have high CI & Power with a low sample size. When you're doing conversion rate optimization - it's usually just "did this person make a purchase?" And usually, your base rate is not less than 1/1000... But in medicine, there are ways to measure the severity of the symptoms and a lot of things are quite rare.
- buildbot 5y ago
  They had over 700 people total, 50% control and 50% infected; which they break down earlier in the same paragraph. The 15 people are those who are hospitalized and the abstract literally says the results from that small group aren’t significant.
skylanh 5y ago
> Here, we studied the effects of the disease in the brain using multimodal data from 782 participants from the UK Biobank COVID-19 re-imaging study, with 394 participants having tested positive for SARSCoV-2 infection between their two scans. 782 participants, 394 of which had positive tests for COVID-19, a further 15 of the 394 were hospitalized due to their symptoms. The interpretation could be: - lung symptoms are not correlated with brain changes - mild infections not requiring hospitalization showed similar pathology to severe infections > What are the quantitative findings of "loss of grey matter"? Page 18 shows the measurements. > What mechanism/s are suspected that might be specific to COVID19? Page 3. > one hypothesis is that an entry point of the virus to the central nervous system might be achieved by crossing the neural–mucosal interface in the olfactory mucosa, and progress from there onto the olfactory bulb in the brain [Meinhardt J, Radke J, Dittmayer C, et al. Olfactory transmucosal SARS-CoV-2 invasion as a port of central nervous system entry in individuals with COVID-19. Nat Neurosci 2021; 24(2): 168-75.]

dasudasu 5y ago

>Our findings thus consistently relate to loss of grey matter in limbic cortical areas directly linked to the primary olfactory and gustatory system. Looks like the loss of smell is due to an impact of the virus on brain tissue. It would be interesting to check if it ever comes back to normal months/years later.

ljf 5y ago
Totally anecdotal, but my wife who was very ill with both covid and then long covid, only lost her smell for a day before it returned. Another friend who had very few symptoms still has no sense of smell 9 months later - her smell can come and go, and she will also now 'miss-smell' smelling nice things as horrible and horrible as nice.

goodoldneon 5y ago

Kind of a tangent, but I get frustrated when researchers publicly release results when one of their groups have a ridiculously small sample size. It’s irresponsible to release results based on 15 people

deleted 5y ago
[deleted]
Xylakant 5y ago
The article is “published” on a preprint server and carries a suitable warning at the top. It’s preliminary, unverified and not reviewed. The target audience is other researchers, not the general public. It’s useful to publish preliminary results based on low sample sizes, it can guide future research. Basically a “hey, we found something we consider interesting, it may be worth having a better look at this.” It’s very dangerous to read too much into this, though - hence the warning at the top.
onlyrealcuzzo 5y ago
I thought this also - but as it turns out - you can make conclusions with really small sample sizes in medicine. For example (this has nothing to do with the paper), if the average rate of some condition - some rare brain tumor - is 1 in 50M - and you take 200 COVID-19 patients and 4 of them have it - and they have several of these tumors - you can have high CI & Power with a low sample size. When you're doing conversion rate optimization - it's usually just "did this person make a purchase?" And usually, your base rate is not less than 1/1000... But in medicine, there are ways to measure the severity of the symptoms and a lot of things are quite rare.
buildbot 5y ago
They had over 700 people total, 50% control and 50% infected; which they break down earlier in the same paragraph. The 15 people are those who are hospitalized and the abstract literally says the results from that small group aren’t significant.

skylanh 5y ago

> Here, we studied the effects of the disease in the brain using multimodal data from 782 participants from the UK Biobank COVID-19 re-imaging study, with 394 participants having tested positive for SARSCoV-2 infection between their two scans. 782 participants, 394 of which had positive tests for COVID-19, a further 15 of the 394 were hospitalized due to their symptoms. The interpretation could be: - lung symptoms are not correlated with brain changes - mild infections not requiring hospitalization showed similar pathology to severe infections > What are the quantitative findings of "loss of grey matter"? Page 18 shows the measurements. > What mechanism/s are suspected that might be specific to COVID19? Page 3. > one hypothesis is that an entry point of the virus to the central nervous system might be achieved by crossing the neural–mucosal interface in the olfactory mucosa, and progress from there onto the olfactory bulb in the brain [Meinhardt J, Radke J, Dittmayer C, et al. Olfactory transmucosal SARS-CoV-2 invasion as a port of central nervous system entry in individuals with COVID-19. Nat Neurosci 2021; 24(2): 168-75.]