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Advanced Neurology COVID-19 and neurodegenerative diseases

to raise the acetylcholine levels and allow binding to the α7 Mechanical thrombectomy remains a challenging mode of
subunit of the nicotinic acetylcholine receptor (α7nAChR). treatment for the management of ischemic stroke, due to
Consequently, this medication drastically suppresses the multiple clots, easy fragmentation of clots, and increased
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release of cytokines such as TNF-α, IL-10, and MCP-1, burden of large clots that are inherent pathological issues of
thereby providing a potential pharmacological therapy for ischemic stroke, as well as the hypercoagulable state of the
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AD patients harboring the SARS-CoV-2 virus. patient. Several potential pathophysiologic mechanisms of
It has been estimated that 74.5% of the AD patients do hemorrhagic strokes in COVID-19 patients include direct
not practice proper mask wearing, while 82.9% of them neuroinvasion, hypertension, diabetes, and endothelial
For hemorrhagic strokes, since one of the
damage.
67,68
seek help from their caregivers. Adhering to the COVID- mainstays of management for COVID-19 patients includes
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appropriate practices is a tremendously difficult task for anticoagulation, the risk of intracranial hemorrhage should
AD patients, thus highlighting the paramount importance be addressed while creating a treatment regimen. 69
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of caregivers. Given the surge of mental illness during
the COVID-19 pandemic, a study by Gan et al. analyzing 8. Conclusion
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the impact of confinement on AD revealed that the rapid
cognitive decline was less pronounced in AD patients Coronaviruses have been proven to be neuroinvasive,
suffering from other neuropsychiatric symptoms. This may further lending support to the notion that SARS-CoV-2
be due to the patients being surrounded and taken care of is also neuroinvasive. Most commonly, the virus infects
by their family members for longer periods than usual. humans through the nasal route and the peripheral nervous
On the contrary, patients with AD residing in retirement system, after which they may either directly damage the
homes were observed to be more anxious (Z = −2.86, BBB by entering cells through ACE2 receptors to invade
P = 0.004, Cohen’s d = 0.81) and depressed (Z = −2.84, the brain or cause a cytokine storm resulting in the release
P = 0.005, Cohen’s d = 0.80) during the COVID-19 crisis. of a large number of proinflammatory cytokines as well
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A study by Boutoleau-Bretonnière et al. focusing on the as mitochondrial dysfunction and apoptosis. The sudden
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burden shouldered by caregivers for AD patients during outbreak of SARS-CoV-2 has wreaked havoc over the
the worldwide lockdown concluded that the behavioral entire world, inflicting a great amount of stress on patients,
changes, especially the agitation of the patients, added to the doctors, and the entirety of the health-care system.
caregiver’s distress, as a result of limited outdoor activities Compared to the general population, patients with pre-
and chances to meet their loved ones. At present, it is an existing neuropsychiatric conditions are more vulnerable
important to integrate the parallel findings concerning to the hazards of COVID-19, and thus, additional attention
COVID-19 and AD and further carry out experimental and care invested in this particular group of patients is
and network analysis in a cohesive manner to substantiate required. Despite the limited information regarding the
the correlations. effects of COVID-19 on neurodegenerative diseases, the
postulation that COVID-19 may accelerate the progression
7. Implications of SARS-CoV-2 infection on of certain neurodegenerative diseases such as AD has been
stroke gaining traction. There is some overlap between AD and
COVID-19 in terms of their predisposing factors and
Acute cerebrovascular disorders are prevalent in inflammatory mediators, thereby making AD a chief risk
COVID-19 patients, particularly those who are seriously factor for mortality of COVID-19 patients. Considering
infected and have pre-existing vascular risk factors. age as a key player in the influence of COVID-19 on
Moreover, males underwent more serious in-hospital neurological disorders, studies have shown negligible
complications and less favorable outcomes following impact of COVID-19 on younger patients of PD, but
ischemic strokes than females. The core pathogenesis demonstrated a great deteriorative effect of COVID-19
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of COVID-19 infection revolves around the cytokine on elderly patients with PD. At present, we are lacking
storm that initially results in endothelial injury and significant data to establish the link between COVID-19
thrombophilia. Consequently, the endothelial cell layer and relatively rare neurodegenerative disorders such as
prevents thrombosis by trapping subendothelial collagen amyotrophic lateral sclerosis and Huntington’s disease.
within a cellular barrier, preventing platelet adhesion, and Several studies indicate that COVID-19 does not seem
releasing anticoagulants, predominantly the nitric oxide. to worsen these disorders, and the associated severity of
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Hence, hypercoagulability is one of the mechanisms the diseases and fatalities attributed to COVID-19 is not
responsible for the development of ischemic strokes, along significantly higher in the infected patients than in the
with other proposed mechanisms such as diminished general population. However, increased complications
alternative RAS pathway and endothelial dysfunction. 64,65 have been reported among the patients in advanced stages

Volume 3 Issue 1 (2024) 7 https://doi.org/10.36922/an.2200