Brain Fog Covid (Long Covid) Cognitive Deficits

In the wake of the COVID-19 pandemic, the world is grappling with an enigmatic phenomenon known as Covid Brain Fog or Long Covid, characterized by persistent symptoms long after the acute infection has passed. Among these symptoms, the most puzzling and disruptive is often referred to as “brain fog.” The term “brain fog” is not a recognized medical term. However, it’s a common word used to indicate alterations in a person’s clarity of mind and capacity for thought or processing. Now, groundbreaking research has shed light on the perplexing cognitive issues associated with Long Covid, linking them to two blood proteins involved in clotting—fibrinogen and D-dimer. This discovery represents a significant step forward in our understanding of Long Covid’s underlying mechanisms.

Published in Nature Medicine, the study offers valuable insights into why some individuals infected with SARS-CoV-2 experience cognitive problems, such as difficulties with concentration and memory, while others do not. These cognitive deficits can persist for up to a year after infection, significantly affecting the quality of life for those who experience them.

Symptoms of Covid Brain Fog

People with COVID brain fog may experience symptoms like:

• Trouble paying attention or inattention
• Short-term memory loss
• Trouble concentrating 
• Difficulty solving problems
• Behavior and mood changes

How long does Covid brain fog last?

The duration of COVID-19-related brain fog can vary widely among individuals. Some people may experience brain fog for a relatively short period, while others may deal with it for an extended time. According to research, COVID brain fog might linger for months after a person gets better. According to one study, problems didn’t start to get better until nine months after receiving COVID. The same study revealed that many individuals continued to have at least five signs of brain fog 18 months following their COVID recovery. There is no fixed timeline for how long COVID-19 brain fog lasts, and it can depend on several factors, including:

1. Severity of COVID-19 Infection: Those who had a mild or asymptomatic case of COVID-19 may experience brain fog for a shorter duration compared to individuals who had a more severe illness.
2. Individual Variability: Each person’s immune system and recovery process are unique. Some individuals may bounce back relatively quickly, while others may take longer to recover.
3. Pre-existing Health Conditions: People with underlying health conditions or vulnerabilities may experience more prolonged brain fog.
4. Treatment and Support: Seeking medical care and following appropriate treatments and support can help manage and potentially shorten the duration of brain fog.
5. Lifestyle Factors: Factors like sleep, nutrition, stress management, and physical activity can influence the recovery process and the duration of brain fog.
6. Age: Younger individuals may recover more quickly than older individuals.

What does COVID brain fog feel like?

While it can vary from person to person, it typically involves a range of cognitive difficulties and can feel like:

1. Difficulty Concentrating: People with COVID-19 brain fog may find it challenging to concentrate on tasks that previously required little effort. Simple tasks may become mentally taxing.
2. Memory Problems: Forgetfulness and memory lapses are common in individuals experiencing brain fog. They may struggle to recall names, dates, or recent events.
3. Mental Fatigue: A pervasive sense of mental exhaustion can accompany brain fog. It often feels like thinking is slower and more draining than usual.
4. Confusion: Individuals may feel mentally disorganized and confused, making it hard to follow conversations or make decisions.
5. Slowed Thinking: Thoughts may seem sluggish, and it can take longer to process information or respond to questions.
6. Difficulty Finding Words: Some people have difficulty finding the right words to express themselves, leading to pauses in conversation or frequent use of filler words like “um” and “uh.”
7. Lack of Mental Clarity: There may be a general feeling of haziness or clouded thinking, as though a mental fog has descended.
8. Reduced Productivity: People experiencing brain fog may struggle with tasks that require creativity, problem-solving, or sustained attention, impacting their work or daily activities.

It’s important to note that these symptoms can range from mild to severe, and not everyone who contracts COVID-19 will experience brain fog. Additionally, while brain fog can be distressing, it is often temporary and improves as individuals recover from the acute phase of the illness.

The Connection Between Blood Clotting and Cognitive Deficits

The research, led by Maxime Taquet and his team at the University of Oxford, delves into the intricate relationship between blood clotting and Long Covid. By analyzing data from the posthospitalization COVID-19 (PHOSP-COVID) study, which collected information from thousands of adults hospitalized with COVID-19 in the UK, the researchers made some striking observations.

One key finding was the association between elevated levels of fibrinogen and D-dimer in the blood during hospitalization and cognitive problems in the months following recovery. Those with higher-than-average fibrinogen levels demonstrated reduced performance in memory and attention tests, as well as self-reported cognitive difficulties. Similarly, individuals with elevated D-dimer levels were more likely to report cognitive issues, fatigue, and difficulty breathing.

Moreover, the research revealed that these findings were not exclusive to the UK population. A parallel analysis of a large U.S. electronic health database confirmed the link between heightened fibrinogen or D-dimer levels during COVID-19 hospitalization and subsequent diagnoses of cognitive disorders, including dementia and mild cognitive impairment.

A Potential Clue to the Brain Fog Mystery

While this study offers crucial insights, it does not provide a definitive explanation of how fibrinogen and D-dimer might cause cognitive deficits. However, one plausible theory suggests that fibrinogen may contribute to the formation of blood clots that disrupt circulation in the brain or potentially interact directly with receptors in the nervous system. On the other hand, D-dimer may reflect clotting in the lungs, which could explain its association with breathing difficulties.

The research is a significant step forward in our understanding of Long Covid, shedding light on one of its most perplexing aspects. Nevertheless, there are still several unanswered questions and challenges ahead.

The Road Ahead: Unraveling Long Covid

While these findings mark a promising development, they should be viewed within a broader context. The study primarily focused on unvaccinated individuals with severe COVID-19, potentially limiting its applicability to the wider population. Many Long Covid patients experienced milder initial infections and are not represented in this research.

Additionally, these blood protein associations do not offer a definitive test for diagnosing Long Covid. They provide insights into the potential risk factors for cognitive deficits but do not present a clear-cut diagnostic solution for current cases.

In terms of treatment, targeting fibrinogen and D-dimer or blood clotting, in general, remains a complex challenge. Anticoagulants have been proposed as a possible treatment but have yet to undergo rigorous clinical trials, and their safety in all Long Covid patients is uncertain.

Nevertheless, this groundbreaking research serves as a catalyst for further exploration into the role of clotting proteins and the intricate biological pathways that underlie Long Covid. Fibrinogen, in particular, continues to emerge as a recurring player in Long Covid research, prompting scientists to intensify their efforts to unlock the mysteries of this persistent condition. As we navigate the evolving landscape of Long Covid, this study reminds us of the importance of continued research and collaboration among experts worldwide. While there may not be immediate solutions, each discovery brings us one step closer to understanding, managing, and ultimately conquering Long Covid’s complex challenges.

References

Nouraeinejad, A. (2022). Brain fog as a Long-term Sequela of COVID-19. SN Comprehensive Clinical Medicine, 5(1), 9.

Asadi‐Pooya, A. A., Akbari, A., Emami, A., Lotfi, M., Rostamihosseinkhani, M., Nemati, H., … & Shahisavandi, M. (2022). Long COVID syndrome‐associated brain fog. Journal of medical virology, 94(3), 979-984.