According to recent US research, Covid-19 may lead to the type of brain changes common in Alzheimer’s disease, and a team of scientists has identified the mechanisms by which it may be causing such impairments.
Cognitive disorders, including dementia, are increasingly being reported as a complication of the highly contagious SARS-CoV-2 virus that causes Covid-19, researchers behind the recent study at the Cleveland Clinic in Ohio have revealed.
“Reports of neurological complications in Covid-19 patients and ‘long-hauler’ patients whose symptoms persist after the infection clears are becoming more common, suggesting that [the virus] may have lasting effects on brain function,” said the authors of the study, which was published this week in the journal Alzheimer’s Research & Therapy.
The researchers’ aim was to uncover the mechanisms responsible for brain-associated complications such as delirium and the loss of taste or smell that are often found in novel coronavirus patients. In order to do so, they compared on a molecular level the host genes of Covid-19 and those responsible for some neurological disorders.
Having collected the data of both Covid-19 patients and people suffering from Alzheimer’s disease, they used artificial intelligence to measure the proximity between them. They also analyzed any genetic factors that might allow the new virus to infect brain tissues and cells, identifying “significant network-based relationships” between Covid and Alzheimer’s. They also concluded that Alzheimer’s patients may be more defenseless against the deadly virus, as they have a decreased number of certain protective antiviral genes.
“While the researchers found little evidence that the virus targets the brain directly, they discovered close network relationships between the virus and genes/proteins associated with several neurological diseases, most notably Alzheimer’s, pointing to pathways by which Covid-19 could lead to Alzheimer’s disease-like dementia,” the Cleveland Clinic stated.
Having proved the overlap between Covid-19 and brain changes common in Alzheimer’s, the researchers will now study the processes by which the novel coronavirus may lead to cognitive disorders and how it might be prevented from doing so. “Identifying how Covid-19 and neurological problems are linked will be critical for developing effective preventive and therapeutic strategies to address the surge in neurocognitive impairments that we expect to see in the near future,” the study’s lead author, Feixiong Cheng, said.
Brain-affecting complications in Covid-19 patients and those ill with other coronaviruses have been confirmed by previous studies, the Cleveland researchers point out. One in five patients who have recovered from the severe acute respiratory syndrome (SARS-CoV-1) or the Middle East respiratory syndrome (MERS) have reported memory impairments, while people suffering from the novel coronavirus have also experienced symptoms such as disorientation, inattention, and confusion. Covid-19 survivors who required intensive care unit admissions might be at an even greater risk of neurological and psychiatric disorders, another study of more than 230,000 patients has shown.
