The NeuroCOVID-19 Syndrome: Cognitive and Psychological Profiles, Physiopathology, and Impact on Neurologically Vulnerable Populations

Book excerpt: The Coronavirus Disease 2019 (COVID-19) global pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has led to the identification of a broad range of post-acute Covid neurological symptoms including cognitive impairments, specific executive dysfunctions with sensorimotor deficits (paresthesia, numbness, or weakness of specific body parts), changes in sleep, changes in taste or smell, hallucinations, emotional distress (anxiety, depression), and fatigue/asthenia. Alarmingly, those post-acute sequelae of COVID-19 (PASC) can occur several weeks after infection, arise after severe, mild, or even asymptomatic SARS-CoV2 infection, and are characterized by the persistence, worsening, or new onset of chronic and debilitating neurological symptoms, which have led to the use of NeuroCOVID syndrome terminology. A link between COVID-19-related neurological symptoms and other neurological diseases has not been clearly established, but an increasing number of studies report an increase in mortality post-SARS-CoV-2 infection and an atypical clinical presentation of COVID-19 in patients with dementia. Another intriguing discovery is that survivors that did not suffer from neurodegenerative diseases before the COVID-19 infection seem to be at high risk for subsequent development of neurological disease and in particular Alzheimer’s disease, and to develop early-dementia symptoms. However, the pathophysiology of those associations is not yet delineated, and more research is needed on NeuroCOVID in both the general population and in specific subgroups affected by neurological disorders. As the COVID-19 pandemic could cause a significant rise in the number of dementia patients in the long term, there is an urgent need to understand how PASC is associated with neurodegenerative disorders or with a worsening of neurologic symptoms in neurologically vulnerable populations.