A study published in the journal Alzheimer’s Disease Reports found that infection with SARS-CoV-2 significantly affects cognitive function in patients with pre-existing dementia, causing rapidly-progressing dementia. Researchers investigated 14 patients with different types of dementia and found that after infection with COVID-19, the differences between dementia subtypes became blurred, and cognitive decline progressed rapidly. Cortical atrophy and white matter intensity changes associated with inflammation are observed in the brain, suggesting that compromised brains have limited defense against novel insults such as infection or dysregulated immune responses.
All dementia subtypes, regardless of patients’ previous types of dementia, behave like the rapidly progressing dementia that follows[{” attribute=””>COVID-19, according to the Journal of Infection with
Since the first wave of COVID-19, neurologists have noticed both acute and long-term neurological syndromes and neuropsychiatric sequelae of this infectious disease. Insights into the impact of COVID-19 on human cognition has so far remained unclear, with neurologists referring to “brain fog.” A group of researchers driven to gain a better understanding of and dissipate this fog investigated the effects of COVID-19 on cognitive impairment in 14 patients with preexisting dementia (four with Alzheimer’s disease [AD]five with vascular dementia, three with Parkinson’s disease dementia, and two with behavioral change frontotemporal dementia), who experienced further cognitive decline after COVID-19.
“Brain fog” is a vague term with no specific attribution to the spectrum of post-COVID-19 cognitive consequences. Based on the progression of cognitive deficits and the association with white matter intensity changes, the authors propose a new term: ‘vanishing memory’. Credit: Journal of Alzheimer’s Disease Reports
Principal investigators Souvik Dubey, MD, DM, from the Department of Neurology, Bangor Institute of Neurosciences (BIN), Kolkata, West Bengal, India, and Julien Benito Leon, MD, PhD, from the Department of Neurology, University Hospital”12 de Octubre, Madrid, Spain explained: “We speculated that there must be some adverse effect of COVID-19 in patients with pre-existing dementia and derived our understanding from the cognitive impact of this viral infection in patients without dementia. However, post-COVID-19 assessment of cognitive impairment in patients with pre-existing dementia is challenging due to several confounders and biases. “
In addition to finding that all dementia subtypes, regardless of patients’ previous types of dementia, behave like rapidly progressing dementia after COVID-19, the team of researchers found that the line between different types of dementia became noticeably blurry after COVID-19.
Co-investigator Ritwik Ghosh, MD, Department of General Medicine, Burdwan Medical College and Hospital, Burdwan, West Bengal, India, expressed concern about the subclassification of dementia. It has become even more difficult in the post-COVID-19 era, where the history of this viral infection plays the most important role. Few patients with a history of COVID-19 without pre-existing dementia have similar phenotypic and imaging brain changes that mimic other degenerative and vascular dementia types.”
The researchers also found that the characteristics of a certain type of dementia changed after COVID-19, and both degenerative and vascular dementias began to behave like mixed dementias clinically and radially. A rapidly deteriorating course is strongly observed in patients with malignant onset, slowly progressive dementia, and who were previously cognitively stable.
Cortical atrophy was also evident at post-study follow-up. Coagulopathies involving small blood vessels and inflammation, which were further associated with brain white matter intensity changes, were considered to be the most important aetiological indicators.
The rapid development of dementia, the addition of further impairments/deterioration of cognitive abilities, and the increase or new appearance of white matter lesions suggest that previously compromised brains have little defense to withstand a new insult (eg, a ‘second hit’ such as infection/disorganized immune response and inflammation). ).
According to Dr. Sofik Dube and his fellow investigators, “brain fog” is a vague term with no specific attribution to the spectrum of post-COVID-19 cognitive consequences. Based on the evolution of cognitive deficits and the association with white matter intensity changes, we propose a new term: “FADE-IN MEMORY” (ie fatigue, decreased fluency, attention deficit, depression, executive dysfunction, slowed information processing speed, and subcortical memory impairment). “
Co-investigator Mahua Gana Dubey, MD, Department of Psychiatry, Berhampur Mental Hospital, Berhampur, West Bengal, India, added, “Amid the various psychosocial effects of COVID-19, cognitive deficits, when accompanied by depression and/or apathy and fatigue in Patients with or without pre-existing dementia require careful assessment as it places additional stress and burden on carers, one of the most important and often forgotten issues that can impede treatment.”
“Given aging populations and dementias globally, we believe that recognition of the pattern of cognitive deficits associated with COVID-19 is urgently necessary to differentiate between cognitive impairments associated with COVID-19 per se and other types of dementia. This understanding will have a critical impact on dementia research. In the future, ”concluded Dr. Sofik Dube.
“Increasing epidemiological evidence for the association of COVID-19 and AD is an increased risk of Alzheimer’s disease with COVID-19, and increased COVID-19 in patients with AD indicates a co-morbidity. Dube and colleagues explain this association in showing that COVID-19 It fundamentally changes the course of dementia regardless of the cause,” Alzheimer’s Disease JournalSemmes Distinguished Chair in Neuroscience at the University of Texas at San Antonio.
Reference: “Effects of SARS-CoV-2 infection on the cognitive function of patients with pre-existing dementia” By Sovik Dubey, Champaditya Das, Ritwik Ghosh, Mahua Jana Dubey, Arka Prava Chakraborty, Depayan Roy, Gautam Das, Ajitava Dutta, Arindam Santra, Samya Sengupta and Juliàn Benito-León February 14, 2023 Available here. Journal of Alzheimer’s Disease Reports.
DOI: 10.3233/ADR-220090