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What Is “Brain Fog” and Cognitive Dysfunction in Long COVID?

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After recovering from the initial COVID infection, many people are experiencing a symptom that is difficult to explain, yet it may be one of the most life-changing and debilitating symptoms they experience. Cognitive dysfunction, often described as “brain fog,” affects how easy it is to think and make decisions. Unfortunately, these cognitive changes are a common symptom associated with many chronic conditions, including Long COVID.

What is Brain Fog?

Brain fog is actually multiple symptoms that affect the ability to think as you once did. Brain fog refers to a cluster of symptoms that may include but are not limited to: difficulty thinking; loss of memory; and problems with concentration. It may be challenging to describe these symptoms, but you may notice that it is challenging to think clearly. You may forget words or it may take longer than usual for you to understand what others are saying, or even harder to read. Some other common symptoms of brain fog can include:

  • Losing your train of thought
  • Difficulty or inability to find the right words
  • Inability to understand or remember things you just read
  • Taking longer to complete tasks that were previously easy for you
  • Forgetting steps to simple tasks
  • Becoming easily distracted and forgetting what you were doing
  • Walking into a room and forgetting why you are there
  • Forgetting someone’s name
  • Unable to stay on or finish a task

This “fog” that seems to settle in the brain can be very frustrating and make it difficult to complete everyday tasks. In many cases, this disruption in cognitive function can negatively impact daily activities, employment, and quality of life.

How is the SARS-CoV-2 Virus Causing Cognitive Dysfunction and Brain Fog?

As more and more Long COVID patients began experiencing cognitive dysfunction or trouble thinking clearly, researchers and the medical community began looking at how the SARS-CoV-2 virus may affect the brain. Studies have found everything from mini-strokes due to reduced oxygen or blood clots, to changes in brain imaging, including changes in gray matter volume.

To date, research has identified several possible causes of cognitive dysfunction in Long COVID, including:

  • Reduced oxygen to the brain due to lung damage
    Those that experienced lung damage during the acute COVID infection may experience reduced oxygen delivery to the brain, resulting in potential cognitive dysfunction.
  • Inflammation in the brain cells
    Research shows that the SARS-CoV-2 virus triggers inflammatory responses throughout the body that can contribute to inflammatory signaling to the brain that causes neuroinflammation. This inflammation can lead to cognitive dysfunction.
  • Reduced oxygen due to impaired oxygen delivery
    Damage to the blood vessels, as well as the presence of micro clots in the blood, can hinder the delivery of adequate oxygen levels to tissues throughout the body, including the brain.
  • Autoimmune response
    The body creates autoantibodies that attack healthy proteins in the body, similar to other autoimmune conditions. 

What are the Long-term Cognitive Effects of SARS-CoV-2?

What can you expect long-term when it comes to Long COVID and brain fog? Are these symptoms short-term or permanent? The answer, unfortunately, is yet unknown. While some people have recovered and returned to baseline cognitive function within a few months, others continue to battle with brain fog for more than a year. In addition, many may experience waxing and waning brain fog symptoms, meaning they may see an improvement, only to experience recurrent brain fog again.

Tips for Living with Cognitive Dysfunction?

There are currently no treatment options for brain fog and cognitive dysfunction associated with Long COVID. However, research is looking into whether constraint-induced therapy (CI Therapy), often used to improve abilities after a stroke, can benefit patients with Long COVID brain fog. However, this treatment option will depend on the exercise capability of the patient undergoing treatment, such as those suffering from PEM.

Tips to Improve Memory Function and Quality of Life

  • Take time to rest and sleep Sleep is the best way to allow the body to heal and recover. Make sure you receive adequate sleep each night. Take time to rest as needed.
  • Eat a healthy diet – Reduce intake of highly refined and processed foods, as well as simple sugars. Some have seen improvements with low histamine diets, gluten, and dairy-free diets, or keto diets. Talk with your physician before making any major changes to your diet.
  • Avoid alcohol and drug use – alcohol consumption and drug use can adversely affect a healthy brain, so it is essential to avoid these substances to allow your brain time to heal.
  • Regular aerobic exercise – even mild aerobic exercise can increase the size of the hippocampus (area of the brain responsible for memory and learning). While even a simple walk can help, keep in mind your other Long COVID symptoms. If you suffer from post-exertional malaise, added exercise will make your symptoms, including brain fog, worse.
  • Mental stimulation – Simple cognitive training games you can find on your phones, such as memory or matching games, can help to improve overall cognitive function. Other options include puzzles, word searches, and crossword puzzles.
  • Organizational tools – utilize tools such as calendars, to-do lists, alarms, or other reminder tools to help with day-to-day responsibilities.
  • Reduce distractions – in order to improve your attention, minimize possible distractions in your environment.

In addition to these helpful tips, talk with your physician about adding possible supplements to your diet. Fish oils, L-Carnitine, vitamin A, B Complex, C, and E, can all help promote brain health and function.

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