SARS-CoV-2 infection represents a high risk for the elderly: analysis of pathogenesis

Abstract

As people get older, age-related alterations occur that lead to increased susceptibility to disease. In the current COVID-19 pandemic, older people are particularly susceptible to a SARS-CoV-2 infection developing into severe disease. The objective of this review was to examine the literature regarding factors that may explain the tendency of this population to develop severe COVID-19. Research articles considered in this review were searched for in EMBASE, PubMed, and Web of Science from December 2019 to December 2020. Citations were screened by two independent reviewers. Studies of the immune system in older individuals found alterations in both the adaptive and innate immune systems. The adaptive system is depressed in its functions, and the innate system is in a pro-inflammatory state that can lead to chronic disease. This proinflammatory state may be related to a severe course of disease in COVID-19. This review shows that the level of evidence supporting an association between immune alterations in the elderly and susceptibly to severe progression of SARS-CoV-2 infection is generally consistent. Preventive measures such as early antiviral treatment are of key importance for prevention of severe progression of COVID19. SARS-CoV-2 infection and pathogenesis Regarding the immunopathogenesis of COVID-19, SARS-CoV-2 uses the renin-angiotensin system (RAS) to enter, replicate, and produce damage in the cell. An important step in SARS-CoV-2 infection is the binding of the viral S protein to its receptor ACE2, a RAS component [5].

An Overview of Vaccines against SARS-CoV-2 in the COVID-19 Pandemic Era

“…Here, we summarize the data with a special emphasis on how to avoid severe COVID-19 and to protect the elderly, who are most vulnerable to COVID-19 [ 67 ].…”

COVID‐19 lockdown consequences on body mass index and perceived fragility related to physical activity: A worldwide cohort study

“…A wide understanding of fragility in the elderly requires a holistic vision including multiple causes: biological, psychological and social aspects, which render seniors more vulnerable to chronic illnesses, emotional stress or limited activities of daily living 27 . Moreover, increased loneliness and reduced family interactions, along with PA restriction, are likely to produce health issues 28,29 that could be explained by alterations in the adaptive and innate immune systems 30 …”

The Three Pillars of COVID-19 Convalescent Plasma Therapy

“…These data have been corroborated by the results of a recent singlecenter study published by our group in 22 elderly COVID-19 patients [34]-the early administration of high-titer CP was safe and led to a rapid viral clearance, halting the progression of COVID-19 and thus resulting in a survival benefit. Aging, indeed, is another example of a physiologic process characterized by an impaired function of the immune system [35]. However, does this mean that CP in younger individuals is not indicated?…”