Brain Fog is a symptom of COVID-19 and migraine? What do COVID-19 ‘long haulers’ and migraineurs have in common?

In the news recently have been a number of articles about the potential long term effects of COVID-19, one of which is ‘brain fog’. This is now a well- recognized potential symptom of coronavirus infection, but what it really is, is unclear. Brain fog is something we have been very familiar with as neurologists, for many years. It is not uncommon in association with migraine, as well as other neurological conditions such as concussion. But what is it?

People with brain fog describe feeling like their brain is “slow”, not performing like usual. Not 100%. Difficulty with concentration, attention and memory are common complaints, but all in all, the feeling tends to be non-specific.

The mechanism of brain fog in migraine is unclear, but may be due to impaired metabolic performance of the brain during an acute migraine, or even between migraines in someone suffering from frequent or prolonged migraine. But..there is clearly inflammation in the brain, blood vessels and meninges associated with migraine. Now with the understanding that COVID-19 causes inflammation in the vessels, scientists have hypothesized that this is potentially leading to brain fog. Could inflammation in the blood vessels, meninges and brain be the common underlying cause of brain fog? More research needs to be done to further characterize brain fog and its causes.

In people with symptoms such as brain fog and a history of migraines, head injuries or COVID-19 infection, workup may need to be done including testing such as MRI of the brain or EEG, monitoring of the symptoms may be important, and treatment may be available for these conditions.

By: Audrey Halpern, MD