Researchers are urging COVID-19 patients to see a neurologist six to eight months after their hospital discharge if they are experiencing cognitive issues, like processing information more slowly or trouble focusing. For those who have recovered from COVID-19, researchers are finding that lingering neurological complications could increase a person’s risk for accelerated aging, mental health disorders and, some suggest, even Alzheimer’s disease.
While SARS-CoV-2, the virus that causes COVID-19, is best known for infecting the respiratory system, a growing body of evidence shows that hospitalized COVID-19 patients suffer from a host of neurological symptoms.
Though most patients who experience loss of smell and taste recover without treatment, Johns Hopkins University Affiliate Staff Majid Fotuhi, an author of the recent study in the Journal of Alzheimer’s Disease, explained that some are experiencing severe neurological effects, from seizures to paralysis and encephalopathy (brain damage).
“Every neurological symptom you can think of has been reported in patients with COVID-19 who are hospitalized,” Fotuhi said.
In the study published this month, Fotuhi and his colleagues reviewed a number of case studies of the neurological symptoms of infected patients. One study from Wuhan, China, showed that 36 percent of hospitalized COVID-19 patients experienced neurological symptoms. A smaller study in France found that one third of patients who left the intensive care unit experienced cognitive symptoms like poor attention, difficulty in decision-making and controlling their behaviors.
He added that COVID-19 patients can also suffer from blood clots, which cut off blood flow and oxygen to vital organs and may lead to strokes.
“When they leave the hospital, they’re not quite the same,” Fotuhi, who is also the medical director of NeuroGrow Brain Fitness Center said of COVID-19 patients who have suffered mini strokes. “They’re a little slower in thinking, they can’t quite problem-solve as they’re used to. If they’re working, they have to put more effort into getting the same job done as before the infection.”
Some strokes are mini strokes or TIAs, which are so mild, they may go undetected and undiagnosed.
“The damage to the brain because of strokes can cause loss of speech, difficulty walking, sudden dizziness, loss of vision,” Fotuhi said. “What’s really interesting is that strokes can be tiny — like the size of a grain of rice or small little pebble — or it could be large like the size of a ping pong ball or an apple.”
What Can Coronavirus Do To The Body?
The virus binds onto proteins known as ACE2, or Angiotensin-converting enzyme 2, impairing the enzyme’s role in regulating inflammation and scar formation. Entering through the nose or mouth, the virus breaches the lungs. It can also impact tissues with ACE2 such as the heart, kidney, liver, digestive tract and possibly the blood vessels.
As the body’s immune response goes awry, a storm of cytokines may follow as the inflammatory proteins triggers widespread inflammation and blood clots. Strokes, liver injury, kidney and heart failure may ensue. Air sacs in the lungs can get flooded with fluid, a hallmark of acute respiratory distress syndrome which is a rapidly progressive disease; in fact, a study from Wuhan found that a third of hospitalized COVID-19 patients developed the syndrome, and more than half of them died.
What Can Coronavirus Do To The Brain?
People’s blood brain barrier may be damaged, Fotuhi suggested, the protective barrier shielding the brain from toxins from infecting the brain. Blood and viral particles, he added, may then travel into the brain and damage neurons.
Fotuhi and his colleagues stated in the study: It is plausible that the cytokine storm, injuries to the brain from strokes, damage to the blood-brain barrier and brain inflammation may cause long-term mental health disorders. Health care systems “may see in the coming years a wave of patients” with conditions such as depression and anxiety.
By studying past pandemics and epidemics, other researchers have also suggested that COVID-19 could cause such symptoms, though it’s still too early to tell whether the virus can catalyze lifelong neuropsychiatric disorders like schizophrenia and Parkinsonism since they only manifested in some patients after years, decades and the next generation.
Past research on SARS-CoV-1, the virus that caused the 2003 severe acute respiratory syndrome (SARS) epidemic, shows that survivors can develop neuropsychiatric disorders after 31 to 50 months of infection. More than half of them suffered from post-traumatic stress disorder and nearly two in five survivors had depression.
“We think that SARS-CoV-2 can reach the brain and it can stay dormant for many years and in fact, can contribute to memory loss, depression, psychosis, [obsessive compulsive disorder] and potentially Alzheimer’s disease,” Fotuhi said.
Coronavirus Causing Alzheimer’s?
Dr. Aaron Ritter, associate staff of neuropsychiatry and behavioral neurology at Cleveland Clinic Lou Ruvo Center, heeded caution against concluding that SARS-CoV-2 may lead to Alzheimer’s.
“Our brains are precious organs and [are] very susceptible to being damaged or injured,” Ritter wrote in an email to Being Patient. “Even after 120 years of research, we still don’t know what triggers Alzheimer’s disease. Factors such as genetics, age, high blood pressure, diabetes, head injury, and even infection may all contribute either singularly or jointly to cause [the] disease.”
Also, further research is needed to pinpoint the biological mechanisms, Ritter added, that can cause the neurological symptoms of COVID-19 patients. Factors such as people’s underlying conditions, genetics and treatment methods could also play a role. While case studies are helpful in describing people’s complications, more research following patients from the point they are hospitalized to after they are discharged are needed.
Meanwhile, Ritter urged those who may be at high risk for neurological disorders such as older adults, those who have compromised immune systems, and people with underlying medical problems, to adhere to social distance and hygiene guidelines.
Scientists are carrying out a clinical trial of Ramipril, a drug approved for treating high blood pressure, heart failure and diabetic kidney disease, to target the Angiotensin-converting enzyme and reduce mortality, the use of ventilators, the severity of the viral infection and the rate of admission to the intensive care unit.
To restore their brain functions, Fotuhi said brain rehabilitation is critical for COVID-19 patients with neurological symptoms. Regular exercise, a healthy diet, and sleep routine can also improve their cognitive functions and boost their odds of recovering.
“The bad things that happen to our brain due to COVID-19 are often reversible,” Fotuhi said. “Our brains have neuroplasticity. Our brains have the ability to grow and heal.“