Research suggests new coronavirus infection causes IQ decline and years of brain aging

When the novel coronavirus disease (COVID-19) first hit in 2019, it brought with it a host of strange symptoms that went beyond just a respiratory illness. One of the most mysterious symptoms at the time was something called “brain fog,” a cognitive problem that included confusion, forgetfulness, and difficulty concentrating.

While other symptoms are changing as the virus mutates, brain fog remains a common complaint among COVID-19 patients, lasting not only during the initial symptoms but for months and even years afterwards. . Several recent studies are trying to understand exactly what this virus is doing to our brains and how to stop it.

said Dr. Ziyad Al Ali, director of research and development at the VA St. Louis Health System. quirks and quarks Host Bob McDonald talks about what he's seen in research about the coronavirus and the brain. Here's part of their conversation.

Let's take a look at some of the effects the coronavirus has had on the brain. What did you see?

one of Main symptoms The phenomenon people experience after being infected with SARS-CoV-2 is colloquially referred to as brain fog. It's a feeling of mental fogginess, an inability to remember things, connect the dots, or think really clearly.

In addition to brain fog, we see people I come back to the clinic with a small stroke. We see a lot of people with headache disorders, sleep disorders, sleep disorders. Many people come to the clinic complaining of tingling in the extremities, legs, and sometimes arms. In rare cases, seizure disorders may occur. In other words, there are a wide variety of health problems in the brain.

Does the new coronavirus actually affect brain function?

There is Research conducted They conducted cognitive tests to measure IQ and measure the ability to cognitively process information, comparing people who had been infected with the coronavirus to those who had not. And there is a clear difference in IQ between those who have been infected with the new coronavirus and those who have not. Even a mild case of COVID-19 can reduce your IQ by about 3 points.

An important caveat to these studies is that most of these studies were conducted from the beginning of the pandemic, when there was no vaccination, the viruses were very different, and there were no antiviral drugs. We also don't really know how permanent the cognitive decline I just described, the 3-point IQ decline, is.

What happens to the brain as it ages?

It is very clear that some individuals experience structural and other imaging abnormalities comparable to those experienced by normal people. 7 years of brain aging.

The hope now is that these effects will be short-lived and that neuroplasticity and other types of mechanisms will allow the brain to return to normal health. However, I think it is yet to be truly characterized and clarified through research.

Why does a virus that enters the lungs have such a big impact on the brain?

that induces brain inflammation. One of the clear signals from the research that we and many others have done over the past few years is that clearly in some people it can cause an inflammatory response in the brain, neuroinflammation, and that can lead to symptoms. That may explain some of it. What some people experience.

It can affect multiple substances that the brain actually relies on to function properly. One of them is cortisol.So People studied this at Yale University And in people who have had a long COVID-19 infection or after a SARS-CoV-2 infection, cortisol levels may drop inappropriately, and cortisol may actually be linked to certain normal functions, including cognitive performance. showed lower levels of cortisol than others, a hormone important for physiological processes. This could explain some of the cognitive impairment seen in some people after infection with SARS-CoV-2.Some research has also been conducted on Indicates low serotonin levels It may also explain some of the symptoms.

However, does the brain not have a protective mechanism called the so-called blood-brain barrier?

By causing inflammation in the brain, it actually make that barrier leaky, so things start leaking into your brain that shouldn't be there. And things that should not go out of the brain or out of the brain. In other words, a leaky blood-brain barrier could also explain some of the symptoms seen after infection with the new coronavirus.

How will this change over time as the virus mutates?

We are currently at a different stage of the pandemic than the one we all experienced in March 2020. There are different viruses. Vaccines are now available. There are antiviral drugs. So all of these drivers are currently reducing the long-term COVID burden to some extent overall.

That doesn't mean SARS-CoV-2 infection is benign or unimportant. We still see people in the hospital with SARS-CoV-2 infection, we still see people suffering from strokes and heart attacks and brain fog and all sorts of other symptoms. But overall, I think the risk has decreased to some extent over the course of the pandemic.

How different are these other effects on the body, brain, and heart from the coronavirus?

The big revelation, or big jaw-dropping moment in this pandemic, was the realization that SARS-CoV-2 infection can yield a very large basket of long-term negative health effects. When we started to go back and think about what happened to people after the Spanish flu, we found that to a significant extent what we're describing now, that people had an increased risk of Parkinson's disease after SARS-CoV-2 infection. Similar historical accounts were found. , headaches, brain fog, etc.

I think one of the big lessons I've learned from this pandemic is that it has a long tail. Sure, we can focus on the acute phase and the tip of the iceberg, but the reality is that there is a much larger disorder and disease beneath the tip of the iceberg.

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Q&A has been edited for length and clarity.