Covid-19 infection is associated with persistent cognitive deficits and with an increase in biomarkers Alzheimer’s in the blood, according to unpublished research presented at the International Conference of the Alzheimer’s Association.
The lead author of one of the studies Thomas Wisniewski of New York University noted that the results “suggest that patients who had Covid-19 may have a acceleration of symptoms and pathology related to Alzheimer’s. “
However, he warned that it is needed “more research longitudinal study to study how these biomarkers impact the cognition of individuals who had Covid-19 in the long term. “
The team studied the presence of some blood biomarkers, neurodegeneration and neuroinflammation in plasma samples from 310 elderly patients hospitalized with Covid-19 in New York.
Biological markers of brain injury, neuroinflammation and Alzheimer’s “are strongly correlated” with the presence of neurological symptoms in Covid-19 patients.
Some biological markers in blood, such as total tau protein (t-tau), light neurofilaments (NfL) or glial fibrillar acid protein (GFAP) are indicators of brain injury, neuroinflammation and Alzheimer’s disease.
From the patients, 158 were positive SARS-CoV-2 with neurological symptoms (the most frequent being confusion due to toxic-metabolic encephalopathy) and 152 without them.
In initially cognitively normal patients, with and without Covid-19-related TMS, the researchers found higher levels of t-tau, NfL and GFAP.
More studies on this
Other research presented at the congress that is held virtually and in Denver (USA), points out that cognitive impairment is correlated with persistent loss of smell in patients recovered from infection.
To do this, they studied cognition and the olfactory sense in almost 300 older adults Amerindians from Argentina who were followed for between three and six months.
More than half showed persistent forgetfulness problems, and about one in four had additional cognition problems, including language and executive dysfunction.
These difficulties were associated with persistent problems with olfactory function, but not with the severity of the original Covid-19 disease.
“We are beginning to see clear connections between Covid-19 and impaired cognition months after infection“So the studies have to be continued and extended over time, said lead author Gabriel de Erausquin of the University of Texas.
People who have overcome the disease but experience cognitive decline are more likely to have a poor physical condition and low oxygen saturation after physical exertion, says another research from the University of Thessaly (Greece).
The vice president of medical and scientific relations of the Alzheimer’s Association, Heather Snyder, said that all this new data “points to worrying trends showing that Covid-19 infections lead to long-lasting cognitive decline and even Alzheimer’s symptoms. “
Synder highlighted that “it is imperative” to continue studying what this virus “is doing in our bodies and brains. The Alzheimer’s Association and its partners are leading the way, but more research is needed.”