New findings on Alzheimer's and Covid-19 disease in elderly; An Integrated review study

In December 2019, a new coronavirus strain called SARS-COV-2 represented a significant challenge for general wellbeing. The Virus can cause mental disability, particularly memory, through the brain parenchyma deterioration and glucose metabolism impairment. Also, elderly persistent home quarantine to prevent the disease, affects their mental condition adversely. Since elders are the most vulnerable group to Covid-19 and there are almost 50 million individuals with Alzheimer's around the world, this review expects to analyze the most recent in Alzheimer's disease and Covid-19 in older adults.

By searching the databases; SID, IranDoc, Google scholar, PubMed, Medline, Scopus, Cochrane Library, Science Direct and using the keywords "Elder", "Covid-19", "Corona virus" and "Alzheimer"; all articles examining association between Covid-19 disease and Alzheimer were
included in the study. Electronic search was performed during 2019-2021.

Findings of 18 selected studies showed; there is a reasonable connection between these two disease which can be proven in both biological and behavioral dimensions. Likewise, cognitive impairment, irritability, mood and communication disorders in the elderly with and without Alzheimer's disease occurred with a steep slope during the Covid-19 quarantine contrasted with the time before the pandemic.

Considering the known pathophysiological connection between these two diseases, the decrease of social and physical activities during isolation and particularly relatives' partition, leads to a decrease in sensory stimulation and increased loneliness in the elderly and also cause restlessness,
cognitive disorders and hallucinations in these people. Although limitations are important to combat the Covid-19 outbreak, it is vital for meet seniors' mental requirements, particularly those with Alzheimer's disease, and their families, and appropriate estimates should be taken to assist them with
enduring the pandemic.