Neurological aspects of COVID‑19 and its impact on the formation of dementia in the elderly

Vishneva Elena Mikhailovna, Vesnina Natalia Sergeevna

Coronavirus infection (COVID-19) caused by Coronavirus 2 Severe Acute Respiratory Syndrome (SARS-CoV-2) has spread rapidly around the world and has had an unprecedented impact on health systems, economies and societies. The clinical picture of COVID-19 primarily affects the respiratory system, causing bilateral pneumonia, but the infection is increasingly recognized as a systemic disease, and neurological manifestations are noted not only in patients with mild symptoms, but more often in patients in serious condition. Elderly people are at high risk of developing severe forms of COVID-19 due to factors associated with aging of all body systems and a higher prevalence of comorbidities, and, therefore, they are more vulnerable to possible severe neuropsychiatric and cognitive impairments. Several cases described such manifestations as insomnia, depressed mood, anxiety, post-traumatic stress disorder and cognitive impairment in a subset of patients after hospital discharge. The potential mechanisms underlying these symptoms are not fully understood, but are likely multifactorial, including the direct neurotrophic effect of SARS-CoV-2, the consequences of prolonged stay in the intensive care unit, the use of mechanical ventilation and sedatives, brain hypoxia, systemic inflammation, secondary effects of drugs used to treat COVID-19 and peripheral organ dysfunction. Chronic diseases such as dementia are of particular concern, not only because they are associated with higher hospital admissions and mortality rates, but also because COVID-19 further exacerbates the vulnerability of people with cognitive impairments. In patients with dementia, COVID-19 often has an atypical picture with changes in mental status that make early detection of cases difficult. COVID-19 has had a huge impact on rehabilitation facilities, where infection and death rates are very high. Measures taken to slow the spread of the virus have forced social distancing and withdrawal of cognitive rehabilitation programs, which may have contributed to loneliness, behavioral symptoms, and cognitive decline in dementia patients. COVID-19 survivors should be periodically assessed using comprehensive cognitive and neuropsychiatric assessments, and special mental health and cognitive rehabilitation programs should be provided for those with delayed cognitive and psychiatric consequences.

Keywords:COVID-19, bilateral pneumonia, cognitive impairment, neurotrophic effect, dementia, mental status, cognitive rehabilitation, Alzheimer's disease.