Physician explains brain fog isn’t just fatigue: Here's what post Covid 19 patients should know

In post Covid-19 patients, brain fog is typically presented as forgetfulness, word-finding difficulty, slowing of processing speed or persistent mental fatigue.

Back in October 2020, amid the Covid-19 pandemic, The New York Times reported that brain fog is defined by memory loss, confusion, difficulty focusing, dizziness, and even having trouble speaking everyday words. In an interview with HT Lifestyle, Dr Anand Kalaskar, general physician, Apollo Clinic, Nigdi explained how brain fog can have detrimental impacts on everyday life.

What is brain fog and what are its symptoms?

Dr Kalaskar said, “Brain fog is a nonprofessional term commonly used to describe a set of cognitive symptoms that include lapses in memory, difficulty with concentration, mental sluggishness, and reduced thought clarity.” This brain fog reportedly affects people who have had mild Covid-19 symptoms as well as those who experienced severe symptoms — it ranges.

Dr Kalaskar added, “In post-Covid-19 patients, brain fog is typically presented as forgetfulness, word-finding difficulty, slowing of processing speed, or persistent mental fatigue. The patients experience themselves as working in a fog and having difficulty focusing or getting things done effectively. The symptoms persist for weeks or months after recovery from acute infection.”

Brain fog vs tiredness

According to Dr Kalaskar, benign tiredness or fatigue usually resolves with rest, is not notably impairing cognition, and is generally nonspecific. Conversely, he said, neurological impairment from Covid-19 'usually includes objective cognitive impairments such as compromised memory, attentional impairment, disorientation, or executive dysfunction'.

“Clinically, if a patient presents with persistent cognitive impairment interfering with work or activities of daily living, particularly if these are accompanied by headache, dizziness, sleep, or mood change, neurological assessment is warranted. Even in patients with mild illness, brain fog can occur, and so complaints of cognition should not be written off as simple tiredness,” Dr Kalaskar said.

Dr Kalaskar added that post-Covid-19, brain fog has been thought to be due to prolonged neuroinflammation provoked by a hyperimmune reaction to infection. “Microvascular damage – micro clots or endothelial dysfunction – has also been thought to incapacitate oxygen and nutrient supply to brain tissue. Central nervous system invasion by the virus, blood-brain barrier disruption, and autonomic nervous system dysregulation have also been proposed. Mental issues like anxiety, depression, and post-viral fatigue also add to these symptoms,” he said.

Can you get tested for brain fog?

Dr Kalaskar shared that neurologists resort to ‘a combination of clinical evaluation, cognitive screening tests, and imaging when necessary’. Routine tests are the Montreal Cognitive Assessment (MoCA) or Mini-Mental State Examination (MMSE) for memory, attention, and executive function, he said.

“In some cases, more detailed neuropsychological testing is indicated. MRI or functional MRI can be advised to exclude structural changes or vascular illness. Blood tests for inflammatory markers, thyroid function, vitamin B12, and D-dimer can be used to exclude other etiologies. Referral to a multidisciplinary long Covid-19 clinic may be indicated in severe or prolonged cases,” Dr Kalaskar said.

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.