The study does not show that COVID-19 causes Alzheimer’s, but it adds to a growing body of research drawing links between coronavirus infection and cognitive function.
David Holtzman, a neurologist who leads a research laboratory focused on Alzheimer’s disease at Washington University School of Medicine in St. Petersburg, said: “In Alzheimer’s disease, pathology begins to build up in the brain, about 20 years before symptoms begin. ” Louis. He said people would have to follow him for decades after the Covid-19 infection to prove himself as a cause.
Instead, a COVID-19 infection can cause inflammation that can exacerbate changes already taking place in the brain, experts say.
“The brain has its own immune response to the pathology involved. [Alzheimer’s] The disease is progressing,” said Holtzman, who was not part of the new study. “When other things happen that cause inflammation in the body that can affect the brain, it’s probably what happens that drives that process as well. Can enhance what is already going on. ,
Other viruses can cause similar inflammation, experts say.
“Covid is one of several dozen potential risk factors that I talked about with my patients,” said Dr Richard Isaacson, a neurologist and director of the Florida Atlantic University Center for Brain Health. He was also not involved in the new study, but is a researcher focused on prevention of the risk of Alzheimer’s disease.
“I tell people to get the shingles vaccine. I tell people to get their annual flu and pneumovax,” and to exercise and eat a brain-healthy diet.
Still, “when there’s smoke, there’s a fire at some point,” he said. “I really believe that this is something that deserves the least amount of attention.”
The latest study, published last week in the Journal of Alzheimer’s Disease, found that there were about seven new diagnoses of Alzheimer’s disease for every 1,000 senior citizens who had a documented case of COVID-19 in the past year, compared with about five new diagnoses. Every 1,000 who didn’t.
Heather Snyder, vice president of medical and scientific relations at the Alzheimer’s Association, noted that the broader effects of the pandemic could have played into the study’s findings.
“The pandemic presented serious delays for individuals seeking a medical diagnosis such as Alzheimer’s, which means these results may be driven by those who already had Alzheimer’s when they were infected but are yet to seek a formal diagnosis. Didn’t,” she said.
The study authors, along with Snyder and other experts, also identified this work as a call for more research on the underlying mechanisms of Alzheimer’s disease that could explain the association.
In the new study, the diagnosis of Alzheimer’s was “mostly temporary,” said Dr., director of the department of neuroscience at the National Institutes of Health’s National Institute on Aging. Eliezer Masalia said.
Masalia, who was not involved in the study, said there is evidence that COVID-19 “can trigger cognitive impairment”, but there are new ways to confirm the link specifically to Alzheimer’s.
A next step would be to follow people at risk for Alzheimer’s after a Covid-19 infection over a long period of time to track biomarkers found in blood and brain scans.
“In the next few years, we’re going to have a lot of important information,” Masalia said. And this is an “extremely important problem” to watch out for given the scale of the disease.
“Imagine how many millions of people like me who are over the age of 60 or 65 have got Covid. Say 5% of them or 10% of them or even 1% of them are at risk,” he said.
“Wow. We’re seeing a lot of people over the next few years that could add to the already huge epidemic of Alzheimer’s disease that we have.”
“Alzheimer’s disease is a serious and challenging disease, and we thought we had turned some of the tide on it by reducing common risk factors such as high blood pressure, heart disease, obesity and a sedentary lifestyle,” said Dr. Pamela Davis said. at Case Western Reserve University and a co-author of the new study.
“Now, so many people in the US have had Covid, and the long-term consequences of Covid are still being revealed. It is important to continue to monitor the impact of this disease on future disability.”