Dr MV PADMA SRIVASTAVA talks to KAUNAIN SHERIFF M about the evolving science around “long Covid” and its impact on the brain, explains the difference between general post-Covid fatigue and severe symptoms which need a specialist, elaborates on the link between Covid and stroke and the biomarkers that can help pre-empt it, and says not every headache warrants an MRI.
Why Dr Srivastava: With many patients experiencing lingering health problems even after recovering from Covid-19—including critical illness, severe headaches and brain fog—concerns over “long Covid” have increased. As head of the Neurosciences Centre at AIIMS, Dr Srivastava is at the centre of the country’s efforts at identifying the reasons, impact and solutions for some of these long-term Covid-linked health problems. The eminent neurologist is also known for pioneering the Acute Stroke Programme (Code-Red), a medical initiative for supporting patients afflicted with stroke and epilepsy.
We are learning about “long Covid” as we go. What has science learnt so far on Covid-19’s impact on the brain?
A lot. But we don’t have all the answers to all the questions yet; it is still a work in progress. The story is still unfolding. Yet, I think, we do have some definite answers. If the question is, does Covid-19 affect the brain during the process of infection and after the infection has subsided? Then the answer is a resounding yes.
But beyond that, the spectrum of how the brain and the nervous system get affected during the Covid infection, and more so after the infection—what is now referred to as “long Covid”—that is an evolving science. There has been a tremendous amount of interest as well as research as to how it impacts the brain and nervous system… There is also a conundrum of mental health issues—which may colour how a patient may present their complaints—and what the spectrum of the diseases that could be. So, in the long run, what it is going to be like, in terms of memory and in terms of degeneration, is still in the realm of research. As of now, very exciting kind of information is being gathered. It is a whole new platform. We do have certain answers as to how it would affect the brain during the infection and also post-infection.
We have brain scans of “long Covid” patients in the UK who had very mild disease that reveal tissue damage and reduction in grey matter. There is also some evidence of brain shrinkage. Do we know if these findings actually mean anything to a patient’s quality of life?
At this point, I would say no. But again, I would go back to the disclaimer that it is still a work in progress. It is actually this group that we are trying to study over a period of time —six months, one year, two years from now. This research is not just in the UK or India. This is a multi-centric and multinational effort, bringing in the caveats of race, ethnicity and geographic uniqueness into it. It will help understand this spectrum better.
Do they develop some memory issues later, do they develop some degenerative disease? We don’t know. Maybe this hypothesis is wrong. But having said that, this is what is being looked into. At this point in time, however, this brain shrinkage means nothing. It does not mean that such a person is going to land up with a major issue. We don’t have any evidence to say that they would be affected. The process of understanding is still underway. Maybe we will know a couple of years later.
Could these brain changes make Covid patients more prone to other neurological deficits or dementia in the future?
That is what is being looked into. Hopefully not. But the changes which are happening clinically are being correlated to serial long-term evaluations—do you continue to have headaches, do you continue to have memory problems? There are scales that have been developed to address these issues. There are certain clinical scales through which we will know if there are subclinical or very subtle memory problems. So, we will know the answers later. It is very premature to say that right now.
There are a few papers that suggest an association between Covid-19 and stroke, even in younger people. Can Covid-19 cause a stroke?
There is one vertical pathogenetic mechanism which suggests that Covid-19 infection may cause increased clotting in the brain, and thereby cause clots in the arteries and a stroke. This has been seen across the board but generally in the elderly and in people who had comorbid conditions such as diabetes, hypertension, and in chronic smokers.
But there have been some case reports about young men as well, who had sudden clotting in large vessels causing brain attacks, with no other vascular risk factor. In fact, at AIIMS, we saw cases of people who had pneumonia or fever, and who just came with a stroke and turned out to be Covid positive. They had bleeding in the brain. There were blood vessel ruptures. Some of them didn’t even have blood pressure.
Now we have very large data that has come in from New York and Europe. There have been groups that have looked into this large data and found that yes, Covid-19 did cause a stroke. But in general, if you looked at the entire spectrum, it didn’t seem to be a humongous increase. It was not like that it was the only predominant complication with Covid-19.
But what was important is that now there are ways to prevent that from happening. That has evolved. There were some biomarkers… We found that if these levels are very high, we can pre-empt things. We can institute some therapeutic mechanism like an anti-clotting drug and tide over certain cases.
We also have devised certain precautionary measures, in terms of how much physical activity one can do when inflammatory markers are high post-Covid. All these things have evolved and we can prevent these problems and ensure that a person has a normal recovery.
So when should one consult a specialist?
So let us talk about headaches. Common migraine is an extremely common phenomenon. What is important to take note of is when the character of the headache changes. If I go out in the sun, or if I have not eaten, I have a headache; that is not the thing. But if there is a change in frequency and intensity, see a specialist.
Second, see if there is an onset of a new kind of giddiness. When you recover from a viral illness and are feeling weak or fatigued, you probably need some supplements. There is body fatigue as well. For this, you can just go to a general physician. But if the giddiness is such that every time you are changing your posture, you have a lot of palpitations, you are feeling dizzy and are almost feeling like falling down and losing balance, then go to a specialist.
And if there is a kind of general sense that I am not as sharp as I was before; I am forgetting things… Generally, when there are complaints of forgetfulness, we dig in deeper. If you tell me that you are not as sharp as you were before, you make a to-do list because you tend to forget. That is generally not so much of a disease process. When this forgetfulness is impacting your daily life, especially in terms of finances, then you need to go to a specialist. That mental fog is probably different.
Any kind of weakness, which is on one side, or anything which is abnormal in terms of loss of sensation, loss of power, loss of balance, then go to a specialist. Other than that, you can be under the follow-up of a general physician, and probably do some course of supplements, focus on nutrition, gradually increase your physical activity and keep a positive outlook. That would help you tide over long Covid.
How do you manage symptoms of brain fog?
Brain fog is a very loose term. It is essentially a constellation of features which have made you unable to do those tasks or sequence of tasks, or multi-tasking, or things that you had taken for granted earlier. Or you don’t have the attention span or foresight or insight into understanding things. That is a kind of executive dysfunction, a kind of fogginess. Generally, it is associated with some mental health issues and sleep problems.
First, if it impacts your daily life, go for a consultation because we may be missing something. Maybe you need testing or neuro-imaging. Second, physicians may give you some supplements along with your normal nutrition. Third, some counselling may help if the rest of it is all okay. Because the brain and mind are so intricately involved that sometimes it is difficult to differentiate.
Fourth, is a positive outlook. Be with friends, connect, sleep well, regularise your lifestyle. These things will definitely pass. It is just a matter of time.
You mentioned neuro-imaging. There are people undergoing brain MRIs. Is that necessary? What are the tests that you would recommend?
I generally don’t recommend too many tests. There is really no point in embarking on expensive, high-end investigations for every single case. A lot of Covid infections probably would not do anything at all. But when they do have complaints, as I have told you, some of the red flags that we have just enumerated, the red flags wherein you need to go to a specialist… And when you actually go to a specialist, they may recommend neuro-imaging after examining you… For every headache, or every time you feel fatigued, you don’t need a barrage of tests; you don’t need an MRI at all. It is only for certain specialised situations when there is a problem which has been detected.
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