If you’ve had COVID-19, it may still be messing with your brain. Those who have been infected with the virus are at increased risk of developing a range of neurological disorders in the first year after infection, new research has found. These complications include strokes, cognitive and memory problems, depression, anxiety and migraines, according to a comprehensive analysis of federal health data by researchers at Washington University School of Medicine in St. Louis and of the St. Louis Veterans Health Care System.
Additionally, the post-COVID brain is associated with movement disorders, ranging from tremors and involuntary muscle twitches to seizures, hearing and vision abnormalities, balance and coordination difficulties as well than other symptoms similar to those of Parkinson’s disease.
The results are published on September 22 in natural medicine.
Our study provides a comprehensive assessment of the long-term neurological consequences of COVID-19. Previous studies have looked at a smaller set of neurological outcomes, mostly in hospitalized patients. We assessed 44 brain and other neurological disorders in outpatients and hospitalized patients, including those admitted to the intensive care unit. The results show the devastating long-term effects of COVID-19. These are part and parcel of the long COVID. The virus is not always as mild as some people think.”
Ziyad Al-Aly, MD, lead author, clinical epidemiologist, University of Washington
Overall, COVID-19 has contributed to more than 40 million new cases of neurological disorders worldwide, Al-Aly said.
Other than having a COVID infection, specific risk factors for long-term neurological problems are rare. “We are seeing brain problems in previously healthy individuals and in those who have had mild infections,” Al-Aly said. “It doesn’t matter if you’re young or old, female or male, or what your race is. It doesn’t matter if you smoke or not, or have other unhealthy habits or conditions.”
Few people in the study were vaccinated against COVID-19 because the vaccines were not yet widely available during the study period, from March 2020 to early January 2021. The data also predates the delta, at omicron and other variants of COVID.
A previous study in natural medicine led by al-Aly found that vaccines slightly reduce -; about 20% -; the risk of long-term brain problems. “It’s certainly important to get vaccinated, but it’s also important to understand that they don’t provide complete protection against these long-term neurological disorders,” Al-Aly said.
The researchers analyzed about 14 million anonymized medical records in a database maintained by the US Department of Veterans Affairs, the nation’s largest integrated health care system. Patients included all ages, races and genders.
They created a controlled data set of 154,000 people who had tested positive for COVID-19 between March 1, 2020 and January 15, 2021 and survived the first 30 days after infection. Statistical modeling was used to compare neurological outcomes in the COVID-19 dataset with two other groups of people not infected with the virus: a control group of more than 5.6 million patients who had no COVID-19 during the same period; and a control group of more than 5.8 million people from March 2018 to December 31, 2019, long before the virus infects and kills millions around the world.
The researchers looked at brain health over a one-year period. Neurological conditions occurred in 7% more people with COVID-19 than those who had not been infected with the virus. Extrapolating that percentage based on the number of COVID-19 cases in the United States translates to approximately 6.6 million people who suffered brain impairments associated with the virus.
Memory problems -; colloquially known as brain fog -; are one of the most common symptoms related to brain and long COVID. Compared to those in control groups, people who contracted the virus had a 77% increased risk of developing memory problems. “These issues resolve in some people but persist in many others,” Al-Aly said. “At this point, the proportion of people who get better compared to those who have long-term problems is unknown.”
Interestingly, researchers noted an increased risk of Alzheimer’s disease in people infected with the virus. There were two more Alzheimer’s cases per 1,000 people with COVID-19 compared to control groups. “A person who has had COVID-19 is unlikely to get Alzheimer’s disease out of the blue,” Al-Aly said. “Alzheimer’s disease takes years to manifest. But what we suspect is that people who have a predisposition to Alzheimer’s disease may be pushed to the limit by COVID, which means they are on a faster path to developing the disease. It’s rare but concerning.”
Also compared to control groups, those infected with the virus were 50% more likely to suffer from an ischemic stroke, which occurs when a blood clot or other obstruction blocks an artery’s ability to supply blood. and oxygen to the brain. Ischemic strokes represent the majority of all strokes and can lead to slurred speech, cognitive confusion, vision problems, loss of feeling on one side of the body, permanent brain damage, paralysis, and death.
“There have been several studies by other researchers that have shown, in mice and humans, that SARS-CoV-2 can attack the lining of blood vessels and then trigger a stroke or seizure,” Al-Aly said. “It helps explain how someone without risk factors could suddenly have a stroke.”
Overall, compared to uninfected people, people with COVID-19 were 80% more likely to have epilepsy or seizures, 43% more likely to develop mental health conditions such as anxiety or depression, 35% more likely to experience mild to severe headaches, and 42% more likely to experience movement disorders. The latter includes involuntary muscle contractions, tremors and other Parkinson-like symptoms.
People with COVID-19 were also 30% more likely to have eye problems such as blurred vision, dryness and retinal inflammation; and they were 22% more likely to develop hearing abnormalities such as tinnitus or ringing in the ears.
“Our study adds to this growing body of evidence by providing a comprehensive account of the neurological consequences of COVID-19 one year after infection,” Al-Aly said.
The prolonged effects of COVID on the brain and other systems underscore the need for governments and health systems to develop public health and prevention policies and strategies to manage the ongoing pandemic and design plans for a post-COVID world, Al-Aly said. “Given the colossal scale of the pandemic, addressing these challenges requires urgent and coordinated – but, so far, absent – response strategies; global, national and regional,” he said.
Washington University in St. Louis
Xu, E. et al. (2022) Long-term neurological outcomes of COVID-19. Natural medicine. doi.org/10.1038/s41591-022-02001-z.