Covid: dementia, lesions… accelerated cognitive decline highlighted in a new study?

A new study confirms the impact of Covid-19 on the brain. This concerns the very first elderly patients infected with the Sars-CoV-2 virus in Wuhan (China), the starting point of the pandemic.

In Wuhan, at the start of 2020, several thousand people flocked to the three hospitals designated to receive the first patients affected by the disease caused by the Sars-CoV-2 virus. It is among these patients that Chinese researchers have selected the large cohort for their study intended to measure, over the long term, possible cognitive changes following the infection.

Published in the journal JAMA Neurology, this study focuses on patients aged 60 and over, hospitalized between February 10 and April 10, 2020 and who survived Covid-19. More than 3,000 people met these criteria, but some were excluded: people who had cognitive or neurological disorders prior to the infection, and people with a family history, heart, liver or kidney disease. In total, more than 1,400 ex-patients were included in the study. The control group was made up of the spouses of these patients, all uninfected.

12% of patients

What conclusion(s) do the authors of this study draw on this particular group and over the long term? Do they go in the same direction as other cognitive and cerebral disturbances? It would seem so, and this especially in people affected by a severe form of Covid-19. The evolution of their cognitive functions was measured at six months and then at one year, via a questionnaire and a telephone interview designed to assess any cognitive decline.

First result: one year following leaving the hospital, just over 12% of the participants had a cognitive disorder (mild cognitive impairment or dementia). In the most lightly infected people, the incidence of these disorders was comparable to that of the control group. Among the most severely affected, however, 15% had dementia and a quarter of mild cognitive impairment one year following leaving hospital. For the authors of the study, these results suggest that in its severe form, Covid-19 seems to be associated with long-term cognitive impairment. And that “the pandemic can substantially contribute
to the global burden of dementia in the future”.

A noter : Before the pandemic, forecasts for the incidence of dementia were already not very optimistic, both at European and global level. By 2050, cases should double worldwide. Even more so, if these results are confirmed.