COVID-19, the disease caused by the SARS-CoV-2 virus, has been associated with a wide array of symptoms beyond the typical fever, cough, and shortness of breath. One of the more curious symptoms reported by COVID-19 survivors is “brain fog”—a catch-all term used to describe thinking difficulties and cognitive symptoms such as memory loss, confusion, difficulty concentrating, and dizziness. Here we’ll explore what brain fog entails, who experiences it, what causes it, and how long it lasts.
What are the cognitive symptoms associated with COVID brain fog?
People describe COVID brain fog as feeling like your brain is full of cotton balls. Mental tasks that were once easy suddenly become difficult. Specific cognitive symptoms associated with COVID brain fog include:
- Memory problems
- Difficulty concentrating or focusing
- Trouble finding the right words
- Haziness in thinking
- Difficulty following conversations or threads
- Feeling consistently confused
- Slower processing speed
- Impaired judgment and decision making
- Poor attention span
Brain fog can range from mild to debilitating. For some, it may include occasional bouts of forgetfulness or zoning out. But others describe it as feeling like you have dementia, unable to focus or think clearly at all.
Who is more likely to experience COVID brain fog?
Brain fog or cognitive dysfunction seems to be a fairly common long-term symptom after COVID-19. Studies indicate:
- Up to 80% of COVID-19 survivors self-report symptoms of brain fog.
- Between 25-30% continue experiencing brain fog 6-9 months after illness.
- Among long-COVID patients (those with symptoms >4 weeks), over 85% struggle with cognitive dysfunction.
Some groups tend to be more vulnerable to long-term COVID cognitive impairment:
- People over 50 years old.
- Those with more severe initial COVID-19 infections.
- People with pre-existing medical conditions like diabetes, high blood pressure, or obesity.
- Individuals who were hospitalized for COVID-19.
However, even young, previously healthy people can experience lingering COVID brain fog, especially if they had moderate or severe COVID-19 symptoms.
What causes COVID brain fog?
Researchers are still trying to understand what causes cognitive symptoms after COVID-19. Some theories include:
- Lingering inflammation – Severe COVID-19 triggers a major inflammatory response. Inflammation crosses into the brain and may continue even after the virus clears.
- Oxygen deprivation – Low oxygen levels, especially in severe illness, damages brain cells.
- Post-intensive care syndrome – Critically ill patients can develop thinking problems after being in the ICU.
- Blood clots – COVID-19 can cause blood clots that reduce blood flow to the brain.
- Brain inflammation – Some studies have found brain inflammation and marker of neural injury in COVID patients.
- Lingering virus – SARS-CoV-2 may persist in neurological tissue and continue to cause damage.
Post-viral brain fog itself is not unique to COVID-19. It has been documented after other viral illnesses like mononucleosis and herpes simplex. The virus triggers an immune response that seems to disrupt normal neurological functioning.
How long does COVID brain fog last?
For most people, COVID brain fog starts to improve within weeks to months after recovering from initial illness, though timelines vary:
| Time after COVID-19 infection | Percentage of patients still experiencing brain fog |
|---|---|
| 1 month | Over 50% |
| 2 months | 15-30% |
| 6 months | 10-15% |
A small percentage of patients are still struggling with cognitive symptoms a year or more later. Risk factors like old age, severity of initial COVID illness, hospitalization, and pre-existing conditions increase risk of long-lasting brain fog.
Doctors have identified a few different recovery timelines when it comes to COVID brain fog:
- Quick recovery – Brain fog resolves within 6-8 weeks.
- Waxing and waning – Symptoms get better than worse again over several months.
- Slow improvement – Gradual resolution over many months.
- Persistent symptoms – Lasting cognitive dysfunction over a year or more.
How is COVID brain fog diagnosed and treated?
There are no standard diagnostic tests for brain fog. Doctors diagnose it based on a description of cognitive symptoms, often coupled with short mental status exams to assess memory, thinking skills, and concentration. Brain scans like MRI usually appear normal.
Treatment focuses on managing symptoms and trying to restore normal cognition:
- Get plenty of rest and sleep.
- Return to normal activity slowly under doctor guidance.
- Perform brain exercises and games to “retrain” your brain.
- Adopt lifestyle habits that promote brain health (diet, exercise, socializing).
- Treat related issues like sleep disorders, anxiety, depression.
- Consider medications like stimulants for impaired alertness/focus.
- Consider occupational therapy to help regain function.
- Join a support group to learn coping strategies.
Be patient, as it can take weeks or months for brain fog to lift completely. Focus on adapting to do what you can and making gradual improvements. If it persists, work closely with your healthcare provider on lifestyle changes, therapy, and medications to restore normal cognition.
What are tips for coping with COVID brain fog?
If you are struggling with lingering COVID-related cognitive symptoms, these self-help tips may help you better cope and function:
- Reduce mental workload – Cut back obligations/tasks. Do demanding cognitive work in short bursts.
- Use memory aids – Write everything down. Set reminders in your phone. Make to-do lists.
- Improve focus – Minimize distractions. Do one task at a time.
- Get organized – Use calendars, labels, filing systems to stay on top of details.
- Ask for help/clarity – Don’t hesitate to have people repeat things or explain better.
- Be patient – Lower expectations for what you can do. Recognize progress may be slow.
- Practice mindfulness – Meditation and yoga can improve cognitive function.
- Prioritize good health habits – Like diet, exercise, sleep, stress management.
Stay connected with loved ones who can provide mental stimulation, humor, and support. With time, lifestyle adaptations, and treatment, most people make a full cognitive recovery.
Conclusion
Brain fog is a common lingering symptom after COVID-19 infection. It can involve issues like confusion, memory loss, difficulty focusing, and slowed processing speed. While the majority of patients see these cognitive issues resolve within a few months, a minority deal with persisting symptoms long after recovery. There are several theories for what causes COVID brain fog, from inflammation to oxygen deprivation effects on the brain. Treatment focuses on managing symptoms, adopting brain-healthy lifestyle habits, and using aids like lists and calendars to help regain normal function. With patience and support, most people eventually make a full cognitive recovery.