The risk of being diagnosed with Alzheimer’s disease increases in the years after coronary infection. However, the researchers emphasize that Covid only reveals the symptoms of an already existing disease.
According to a Danish study, corona infection significantly increases the risk of Alzheimer’s diagnosis in the next twelve months.
Compared to uninfected people, the doctor diagnosed Alzheimer’s disease 3.5 times more often in infected people, writes Pardis Zarifkar and her team in the journal “Frontiers in Neurology”. However, two German experts point out that, from their point of view, corona infection in the examined cases did not cause Alzheimer’s disease, but only revealed the symptoms of the existing disease. The study was previously reported by other media.
Zarifkar’s team from the University Hospital in Copenhagen evaluated Danish health data and compared how often certain neurodegenerative diseases occurred in people with and without coronary infection over a period of one year. They found a link similar to that of Alzheimer’s disease, for example Parkinson’s disease and cerebral infarction. However, the researchers emphasize that for most of the diseases studied – including Alzheimer’s – the effect was not greater than after the flu or bacterial pneumonia.
Respiratory diseases affecting nerve cells
It has long been known that such respiratory diseases lead to inflammatory reactions that can increase the harmful effect on nerve cells in the brain, explained Anja Schneider, the leader of the research group at the German Center for Neurodegenerative Diseases (DZNE) in Bonn. Press Agency. The increased risk of diagnosis shown in the study could be due to the fact that the inflammatory reaction associated with the corona accelerates nerve cell damage and the symptoms become more visible faster.
Peter Berlit, general secretary of the German Society for Neurology (DGN), told dpa that the study could not conclude that a person after a coronary infection has an increased risk of developing Alzheimer’s disease in a later period. It has only been shown that symptoms are more often diagnosed after infection. He points out that external factors – such as the loss of a familiar environment because one has to go to the clinic – can also lead to pre-existing Alzheimer’s disease becoming symptomatic.