British researchers have tried to understand the mechanisms behind the evolution of long Covid symptoms. More precisely, it was a question of knowing more about the possible cognitive damage following the infection.
Long Covid is none other than the persistence of coronavirus symptoms in some patients over time, which concerns between 5 and 15% of cases . However, the list of these symptoms is rather long:feeling of mental slowdown, fatigue, shortness of breath, concentration problems, joint or chest pain and headaches. In December 2020, a French hospital tried to understand this phenomenon. Among the possible causes, the doctors had mentioned stress due to the epidemic and especially the persistence of an inflammatory reaction or the virus itself.
Other doctors have tried to find out more, as shown in a publication in the journal eClinicalMedicine on April 28, 2022. Led by the University of Cambridge (UK ), the aim of this work was to understand the potential cognitive damage caused by the long Covid. During the period March-July 2020 (i.e. six months after the start of the pandemic), the researchers administered cognitive tests to 46 patients Covid. The results were then compared with data from 66,000 people in the UK population.
This work is based on verbal analogical reasoning tests, which assess people's ability to recognize relationships between ideas and to think methodically. According to the results, hospitalized patients generally had lower scores . In addition, they testify to a slower processing of information in these same patients. Above all, the authors of the study made a rather disturbing announcement. Covid patients can lose up to ten IQ points . However, this type of cognitive decline normally occurs naturally between the ages of 50 and 70.
British scientists have cited several reasons for this cognitive damage. First, any severe coronavirus infection can reduce blood supply to the brain . These include blocked blood vessels, microscopic bleeding and an overactive immune system. Also, the part of the brain responsible for attention, complex problem solving and memory uses glucose less efficiently .
The study therefore highlights the fact that many people suffered persistent cognitive damage after the disease. However, the researchers also claimed to have already observed gradual improvements in some patients , a sign that this same damage is not irreversible.