I’m sorry to interrupt our fascinating study of dementia, but this new article about COVID-19 is somewhat related and very timely, so I thought I should bring it to your attention.
Last week a report was released of a study conducted by Dr. Adam Hampshire of Imperial College London. This has been widely reported, I have some links in the show notes at http://RunningAFEVER.com/245. The results are new, so they have not been peer-reviewed. 84,000 people who had recovered from COVID-19 were studied and found to perform worse on cognitive performance tests than demographics would normally predict. The difference was found to be equivalent to a 10-year decline or an 8.5-point difference in IQ.
The specific test was the Great British Intelligence Test(GBIT). This appears to be legit, but on the website, which you can find in the show notes and go take the test yourself if you like. It says there that the test and questionnaire should take about 30 minutes. So this is not the kind of rigorous testing that a neuropsychologist might perform.
I’m not saying I’m skeptical. I don’t want you to get that idea. I mean, we are a year into this and hopefully most scientific effort has been focused on developing a vaccine. Going back to episode 220, which was a general and hopeful look into long-term effects, I was disappointed. And that’s what I’m feeling here. But it does provide some more data points that may be helpful in the overall scheme of things.
We’re interested in long-term effects. I think this might affect how seriously people take the precautions suggested by the CDC and others. And the study did find that COVID-19 “may cause long term health changes”.
One interesting datum is that in the GBIT there was a decline in performance between the ages of 20 and 70. Now there is some debate about this. And I have to admit I haven’t studied it very much. But I remember when I was looking into it about 17 years ago I found that intelligence tests adjust for factors such as age, and that raw scores should increase over time. This may be due to to accumulated intelligence, in other words, as we get older we have accumulated more learning, vs. our mental capacity. I found another article on the MIT site which lists several types of cognitive function with differing peaks, ranging from fluid intelligence, meaning our ability to think quickly and recall information, which peaks at age 20 (though this is more complex, some areas peak as late as 40). And the ability to evaluate the emotional states of others, which peaks in the 40’s and 50’s.
Anyway, I’m getting a little on a tangent here, but long-time listeners know I am more interested in this topic than any other. In short, I believe the GBIT, which is hardly comprehensive, measured fluid intelligence, based on reading the study report itself.
Possible causes include hypoxia, or oxygen starvation, which may be the reason that cognitive impairment has been seen in patients with other respiratory illnesses. Sometimes cognitive impairment was the first noticed symptom. Of course there are problems with any statistical information, for example, maybe people with lower cognitive function are more likely to get the disease. There’s nothing definitive here, and I don’t want to get into the vagueness.
The report is short, especially if you exclude all the text about methods, etc. So I recommend you read it yourself. The link to the report as well as all the other references are at RunningAFEVER.com/245 as usual.
What I take from this, is an increased awareness of the need for continued caution and vigilance. As I record this on Halloween, 2020, statistics for the United States are as bad as they have ever been. The spread of the disease is not slowing down. R Naught, the measure of contagion, is still greater than 1 in all 50 states. And as you can see by today’s episode, the disease is very serious. It’s not like the flu. Even if you get over it, there may be serious long-term effects.
I hope this has been a beneficial episode, if not a very happy one. Be careful out there.
References:
https://www.medrxiv.org/content/10.1101/2020.10.20.20215863v1
https://globalnews.ca/news/7425712/coronavirus-ages-brain-10-years/
https://www.webmd.com/lung/news/20201028/study-shows-covid-19-may-cause-brain-aging
Great British Intelligence Test:
https://gbit.cognitron.co.uk/account/consent?next=/ex/task/rs_prospectiveMemoryObjects_1_immediate
https://news.mit.edu/2015/brain-peaks-at-different-ages-0306#:~:text=Scientists%20have%20long%20known%20that,then%20begins%20a%20slow%20decline.
https://en.wikipedia.org/wiki/Hypoxia_(medical)#:~:text=Hypoxia%20is%20a%20condition%20in,a%20region%20of%20the%20body.