COVID And The Brain: ‘You Should Be Afraid’
UC San Diego Health doctor highlights neurological complications of virus
Monday, August 10, 2020
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Horror explores themes relating to the brain be it about disembodied brains on a rampage or how someone can control your mind or what happens to your gray matter when you're zombified. Now COVID-19 is serving up real horrors about how it can affect the brain. UC San Diego Health neurointensivist Dr. Navaz Karanjia explains what the dangers are.
Aired: August 10, 2020 | Transcript+ Subscribe to this podcast
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"World War Z" novel by Max Brooks
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Horror frequently explores themes relating to the brain be it about disembodied brains on a rampage or how someone can control your mind or what happens to your gray matter when you're zombified. Now COVID-19 is serving up real horrors about how it can affect the brain. UC San Diego Health neurointensivist Dr. Navaz Karanjia explains what the dangers are.
As someone who is fascinated by how the brain works, I love when pop culture finds creative ways to explore our fears and fascination with an organ that still mystifies us on many levels. This leads me to something else I love, picking the brains of neuroscientists. In this case I spoke with Karanjia about how COVID affects the brain, which is an area of the virus that I have not seen discussed that often.
Karanjia's specialty is neurocrtical care, and the technical term for her position is a neurointensivist, which she said "means I take care of any patient who has a brain problem severe enough to land them in the ICU, so I take care of patients with strokes, seizures, bad brain tumors, brain hemorrhages, brain infections, brain trauma, etc."
How COVID attacks the brain
Now her area of expertise is being tapped as doctors are seeing more neurological complications from the coronavirus.
Karanjia outlines three ways by which COVID can attack the nervous system: "One, by direct viral invasion, coming through the bloodstream or by infecting the nerves in the nose — the olfactory nerves — that are attached to the brain and crawling along them to the brain. Two, by the body creating antibodies that attack the brain and nervous system. And three, by causing systemic inflammation to the other organs and blood vessels that can cause blood clots to form all over the body, that may get shot up through the heart to the brain, or that may form in the brain itself.”
But there are some facts emerging about the virus and the brain.
"The thing that's tragic and fascinating about COVID is it can affect the brain and nerves in so many different ways," Karanjia said. "For example, the damage it causes to blood vessels can lead to strokes and brain hemorrhages in up to 6% of hospitalized patients. Low oxygen levels caused by the lung and heart injury can damage the brain. And the inflammation itself from the infection can affect the brain and the nerves, causing confusion and delirium in the majority of patients with severe COVID. It can also directly affect the nervous system. In mild cases, it can cause loss of taste or smell, or in severe cases it can cause meningitis. We've also seen it cause, an autoimmune reaction, where the body's antibodies to the virus accidentally attack the brain and nerves, and that can cause life threatening issues like brain swelling and Guillain-Barre syndrome."
And finally, there are psychiatric symptoms that are being reported.
"We're seeing people with hallucinations, even psychosis, even after mild COVID disease, which could be from brain involvement," Karanjia said. "One COVID patient in her 50s, with no psychiatric history, with mild symptoms of fever, cough, and loss of taste and smell, was hospitalized for three days requiring minimal oxygen treatment. After discharge her husband reported she was confused and doing strange things like taking her coat on and off repeatedly, and reporting visual hallucinations of monkeys in her house, as well as auditory hallucinations. And then there's the anxiety, depression and PTSD due to the psychological trauma of being hospitalized with a frightening disease."
The neurological problems related to COVID can range from mild like headache or loss of taste and smell, which have been commonly documented in symptomatic patients, to more concerning things like difficulty concentrating or thinking, which has been called brain fog, to confusion and delirium. The virus is creating neurological complications by causing strokes or depriving the brain of oxygen as well as by attacking the brain cells directly.
"So there are plenty of reports of meningitis and encephalitis, or inflammation of the brain, from the virus infecting the brain," Karanjia stated. "We also know that even in minimally symptomatic patients, when they have an MRI, they can demonstrate evidence of inflammation of the brain even if they don't have neurologic symptoms. So the exact number of patients that that are having neuro-invasion is unclear. But because an early symptom of COVID is commonly the loss of smell and taste, which is carried by the nerve from the nose that goes directly to the brain, the olfactory nerve, we are concerned that direct invasion of the neuro-system is happening in a much larger percentage of patients than we would normally expect with a virus like this."
COVID and strokes
The damage a stroke can cause to a patient is something that doctors are familiar with. Karanjia is particularly concerned with how COVID can create these life threatening complications.
"We've seen, strokes from those blood clots I talked about, brain swelling, seizures, coma from infection and inflammation of the brain, paralysis from autoimmune attacks on the nerves,” she said. “What I'm seeing most commonly is delirium in the very sick COVID patients. And we've seen a number of strokes as well, both of which can have permanent consequences. Although they happen more frequently, the more severe the patients’ COVID symptoms, it's important to note that these neuroemergencies can even happen to patients with mild respiratory symptoms. We've seen some young patients with minimally symptomatic covid with no stroke risk factors come in with devastating large strokes."
Karanjia wants people to be aware of the symptoms that signal a stroke be it from COVID or from other health reasons.
"One of the ways to remember the symptoms of stroke is the mnemonic BE FAST," she explained. "B for sudden balance problems. E for sudden eye or visual problems. F for facial drooping. A for arm weakness. S for speech problems. And T is time to call 911 because we have excellent treatments for stroke that can return up to 70% of patients back to a functional life, but they only work if they're started within hours of symptom onset — 2 million neurons are dying every minute you're having a stroke. So that's why it's so important to call 911 immediately. And that's not an exhaustive list of all the symptoms that could be indicative of neuro complications. If you see somebody convulsing, confused, sleepier than usual, with a bluish tinge to their face, or just generally not acting like their normal self. Call 911."
But Karanjia also wants to point out that there are effective treatments for some of the side effects COVID is causing.
“There are a number of promising medications under investigation. But of course, the best treatment will be to prevent getting it in the first place,” Karanjia said. “We already have excellent treatments for stroke. For example, we have clot busting drugs and procedures to remove brain clots that can return folks to a functional life up to 70% of the time as long as they reach the hospital within hours of their symptoms. And we also have excellent neurocritical care treatments for the other conditions.”
Long term effects of COVID
Again, since coronavirus is a novel strain that doctors and scientists have not seen before, there is no way to know what the long-term effects of the disease might be. So even if you have recovered from the obvious symptoms of COVID you may have lingering problems for an as yet unknown length of time.
"On MRI, some patients with no symptoms except for loss of smell have brain inflammation. And for some of those patients, their symptoms are still ongoing. So we don't know how long they will last or what percentage of people will get them or whether there are other long term effects. That's why there are studies going on to investigate those long term effects," Karanjia said.
One of the unique things about COVID is the effect it has on the blood vessel lining that causes clots everywhere in the body.
“This is not something we've seen from common viruses before, and that's why the effects of COVID seem to be more devastating and causing more widespread organ damage than we're used to seeing with other viruses," Karanjia said. "In addition to the specific effects of COVID, we are also concerned about the number of patients that may develop Post Intensive Care Syndrome, or PICS, which can cause memory and thinking problems similar to Alzheimers’ Disease, psychiatric problems like PTSD, and physical problems like ongoing fatigue and weakness. Up to 50% of patients that survive an ICU stay can develop PICS. PICS clinics and COVID neuro clinics are now opening around the country to help patients with these long term effects."
What being a novel coronavirus means
COVID-19 is a novel coronavirus and that means scientists have only been able to study it since it was first discovered late last year. That also means new information is continually being discovered as studies evolve with more patients over more time.
"Any new disease is a challenge because there's limited data at first," Karanjia explained. "It takes years to design studies, recruit patients and perform the study in a scientifically rigorous and ethical way. But now you've got a highly infectious disease that progresses rapidly over days to weeks. The longer-term effects will take time to discover. So, for example, during the Spanish flu pandemic of the early 20th century, nobody knew what the effects would be on babies. So we needed decades of follow up to discover what those effects were."
But with the Internet, social media, and the politicizing of the pandemic there is a lot of misinformation and changing information that can be difficult for people to filter through. A similar situation occurred during the Spanish flu.
“Unfortunately, during the Spanish flu pandemic, for example, people were also desperate,” she said. “Some were hawking quinine as a treatment, which it's not for the flu, and protesting against mandatory mask laws then as well. But as it became clear that quinine didn't work against the flu and mask wearing did help people eventually came around, as I am optimistic they will today. So, yes, it is a challenge to get good information out there because it takes time to do good studies and then get the answers out there in a way so people know they're legitimate. But what's important for people to understand is that scientists are still going through the process of doing those studies and we need patients help to participate in them so we can understand this disease.”
Bottom line: 'Wear a mask!'
"I think there are a number of things that Max Brooks got right in his zombie apocalypse book," she said. "So one of the most salient ones, I think, is because no one wanted to believe that a serious pandemic was occurring in the book. There was a delay in using the right tactics to combat it, which resulted in a lot of preventable death and suffering. So while COVID is not a zombie apocalypse, it would be great if we could learn from 'World War Z,' take this pandemic seriously and initiate appropriate containment tactics to prevent it from snowballing as opposed to the book."
If there is one thing Karanjia hopes people take away from her discussion here it's this:
"You SHOULD be afraid of getting COVID, because I’ve seen it kill young healthy people or leave them horribly disabled," she told me. “Many of my patients' families chose to let their loved ones die because the brain damage they sustained was so severe. I have now seen multiple young COVID patients with neurologic complications that resulted in their death or left them terribly disabled. I have not seen that with the flu in over 15 years of treating patients. We can get through this faster and with less economic damage and lives lost if we all wear masks and social distance.”
It is really that simple.
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