Long Covid: Brain Fog, Fatigue and Blood Clots – Study

A UK study suggests that blood clots in the brain or lungs, including brain fog and fatigue are some common symptoms of “long Covid”. Experts say it’s a combination of someone’s health before, the acute event itself and what happens afterwards that lead on to physical and mental health consequences. 

According to the Department of Health and Aged Care, problems with memory and concentration, also referred to as brain fog, are some of the most common symptoms of long Covid, with shortness of breath and fatigue. 

Catherine Bennett, chair of epidemiology at Deakin University, says the condition can be temporary and mild, or continue long-term and prevent people from being able to work and function at their normal level. “It can be things as simple as poor concentration, but it can be more disabling, it can be feeling confused, or being very slow in thinking, it can mean forgetfulness or mental fatigue, or not finding the right words.” Bennett said it can interfere in day-to-day activities. 

A new study established that identifying predictors and possible mechanisms was a key step in understanding post-Covid brain fog. Researchers examined more than 1,800 British people hospitalized with Covid-19 between early 2020 and late 2021 who had self-reported issues and had cognition tests with clinicians six and 12 months after hospitalization. They identified two possible biomarkers. However, there were numerous limitations in the biomarker study, including the cohort studied and the lack of information on their previous cognitive state. 

But Bennett believes understanding biomarkers could help identify risk factors and recognize groups of people who might be at risk of long Covid and ongoing cognitive issues.  She explained biomarkers can be important to help identify who they are and look at the risk factors that put people in that group. “And also, importantly, help us understand some of the mechanisms of the condition that could point to other ways to help with therapy.” 

The study highlighted higher levels of the protein fibrinogen and protein fragment D-dimer for brain fog. Both proteins are involved in blood clotting, thus results support the hypothesis that blood clots are a cause of post-Covid cognitive problems.