Fatigue and Cognitive Impairment in Long Covid Patients

October 10, 2022

In a recent study, researchers asked whether fatigue and cognitive impairment are indeed associated with a COVID-19 infection, and whether fatigue and cognitive impairment are separate conditions or appear together in the same patients. 969 people with a history of COVID-19 infection at least six months prior to the study were compared to a group of people who were not infected with COVID-19. 

Study results showed that 19% of people who had COVID-19 suffered from clinically relevant fatigue; this figure fell to 8% for those without prior COVID-19 infection. Acute COVID-19 symptoms – especially altered consciousness, dizziness, and myalgia (muscle pain) – were associated with a higher likelihood of fatigue. Factors such as female sex, younger age, and history of depression were also associated with post-COVID fatigue.

The authors observed that fatigue severity decreased over time; however, more extended and detailed studies are needed to confirm this trend.

Cognitive impairment was also a more prevalent symptom among people who suffered from COVID-19, with 26% of patients experiencing mild and 1% experience moderate cognitive impairment. However, the factors associated with cognitive impairment differed from those associated with fatigue. Cognitive impairment was associated with factors such as older age, male sex, and a history of neuropsychiatric diseases.

Researchers concluded that fatigue and cognitive impairment are more frequent in people who suffer from COVID-19, but these two conditions are separate and triggered by different molecular mechanisms. While the authors did not investigate this further, they highlight the possible connection between post-COVID fatigue, inflammation markers, and autoimmune disease. They point out that there is evidence that fatigue and increased autoimmunity are frequent consequences of infection from several viruses, including SARS-CoV-1, MERS, Epstein-Barr, herpes, and hepatitis viruses. Fatigue is also a symptom of several autoimmune diseases, including multiple sclerosis, and evidence suggests a correlation between COVID-19 symptoms and inflammation markers. The authors recommend further studies to shed more light on these emerging connections.