New Delhi: Since the outbreak of COVID-19, neurologists have been noticing acute and long-term neurological impacts of the infectious coronavirus disease.
In the absence of clear insights into COVID’s effect on human cognition, neurologists have often referred to it as ‘brain fog’.
A team of health experts from West Bengal has proposed a new term ‘Fade In Memory’ – that is, “fatigue, decreased fluency, attention deficit, depression, executive dysfunction, slowed information processing speed, and subcortical memory impairment” — to better describe the cognitive effects, reported Timesnownews.com.
The researchers studied the effects of COVID-19 on cognitive impairment in 14 patients with pre-existing dementia. Of the patients who were studied, 4 already had Alzheimer’s, 5 vascular dementia, 3 Parkinson’s and 2 behavioural variant of frontotemporal dementia.
The results of the study, published in Journal of Alzheimer’s Disease Reports, showed that patients with different subtypes of dementia experienced rapidly progressive dementia after contracting coronavirus infection.
“As the ageing population and dementia are increasing globally, we believe pattern recognition of COVID-19-associated cognitive deficits is urgently needed to distinguish between COVID-associated cognitive impairments per se and other types of dementia,” said Dr Souvik Dubey, from Bangur Institute of Neurosciences (BIN) Kolkata’s Department of Neuromedicine.
The team found that irrespective of the patient’s previous dementia type, the line of demarcation between different types of dementia became extremely blurry, post-COVID.
Researchers observed that characteristics of a particular type of dementia changed following COVID-19, and both degenerative and vascular dementia started behaving like mixed dementia — clinically and radiologically.
Patients with slowly progressive dementia, who were previously cognitively stable, were seen to take a rapidly and aggressively deteriorating course.
The researchers explained that the rapid progression of dementia, further impairments/deterioration of cognitive abilities, and the increase or new appearance of white matter lesions suggest that previously compromised brains have little defence to withstand a new onslaught, that is, a ‘second hit’ like infection/dysregulated immune response and inflammation.
