People who have contracted COVID-19 are at higher risk for developing a number of neurological conditions within the first year after infection, according to a new study.
A year-long study published Thursday in Nature Medicine analyzed about 14 million medical records in a database from the U.S. Department of Veterans Affairs. Evaluating 44 brain and other neurological disorders, researchers found that disorders occurred 7% more in patients who had been infected with COVID compared to similar patients who had never been infected.
The team concluded that about 6.6 million Americans had brain impairments linked with their COVID infections.
"We're seeing brain problems in previously healthy individuals and those who have had mild infections," Dr. Ziyad Al-Aly, senior author and clinical epidemiologist at Washington University, said in a release. "It doesn't matter if you are young or old, female or male, or what your race is. It doesn't matter if you smoked or not, or if you had other unhealthy habits or conditions."
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Brain-related disorders included strokes, cognitive and memory problems, depression, anxiety and migraine headaches, according to the report. Movement disorders were also symptoms of a post-COVID brain, including tremors, involuntary muscle contractions, epileptic seizures, hearing and vision abnormalities, and balance and coordination difficulties.
The most common brain-related symptom was memory impairments, typically referred to as brain fog, where there was 77% higher risk for people who were infected with COVID.
"Our study provides a comprehensive assessment of the long-term neurologic consequences of COVID-19," Al-Aly said. "Past studies have examined a narrower set of neurological outcomes, mostly in hospitalized patients. We evaluated 44 brain and other neurologic disorders among both non hospitalised 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 long COVID. The virus is not always as benign as some people think it is."
Al-Aly noted that overall, COVID-19 has contributed to more than 40 million new cases of neurological disorders worldwide.
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Among adult survivors of COVID-19 under age 65, 1 in 5 continued to deal with at least one symptom of long COVID such as brain fog, blood clots, kidney failure, respiratory issues, cardiovascular problems and muscular conditions.
The risk of long COVID was even higher for virus survivors over age 65, with 1 in 4 dealing with lingering symptoms after their initial illness.