COVID-19 neuropsychiatric repercussions: Current evidence on the subject

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has affected the entire world, causing the coronavirus disease 2019 (COVID-19) pandemic since it was first discovered in Wuhan, China in December 2019. Among the clinical presentation of the disease, in addition to fever, fatigue, cough, dyspnea, diarrhea, nausea, vomiting, and abdominal pain, infected patients may also experience neurological and psychiatric repercussions during the course of the disease and as a post-COVID-19 sequelae. Thus, headache, dizziness, olfactory and gustatory dysfunction, cerebrovascular disorders, neuromuscular abnormalities, anxiety, depression, and post-traumatic stress disorder can occur both from the infection itself and from social distancing and quarantine. According to current evidence about this infection, the virus has the ability to infect the central nervous system (CNS) via angiotensin-converting enzyme 2 (ACE2) receptors on host cells. Several studies have shown the presence of ACE2 in nerve cells and nasal mucosa, as well as transmembrane serine protease 2, key points for interaction with the viral Spike glycoprotein and entry into the CNS, being olfactory tract and blood-brain barrier, through hematogenous dissemination, potential pathways. Thus, the presence of SARS-CoV-2 in the CNS supports the development of neuropsychiatric symptoms. The management of these manifestations seems more complex, given that the dense parenchyma and impermeability of brain tissue, despite protecting the brain from the infectious process, may hinder virus elimination. Still, some alternatives used in non-COVID-19 situations may lead to worse prognosis of acute respiratory syndrome, requiring caution. Therefore, the aim of this review is to bring more current points related to this infection in the CNS, as well as the repercussions of the isolation involved by the pandemic and to present perspectives on interventions in this scenario.

Post-COVID-19 Syndrome in Outpatients and Its Association with Viral Load

“…Viral load is another important parameter to know ( Table 2 ) [ 16 ] for whether people can develop post-COVID-19 symptoms. Our results show that, at a low Ct value [ 15 , 16 , 17 , 18 , 19 , 20 ], patients have between 15 to 20 post-COVID-19 symptoms; likewise, this is reflected when analyzing patients who had an intermediate Ct [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ] who presented between 6 to 11 symptoms, and, finally, there were patients with a low Ct [ 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 ] who had few or no symptoms ( Figure 3 A). Therefore, a Pearson correlation was performed between the Ct value and the number of post-COVID-19 symptoms (r = 0.…”

“…SARS-CoV-2 infection can reach the CNS through the olfactory tract and access the cortex, basal ganglia, and midbrain, which may be affected during propagation [ 23 ] supporting the existence of neurological symptoms such as headache, anosmia, dysgeusia, dizziness, and impaired consciousness; thus, olfactory dysfunctions (OD) throughout the pandemic became part of the symptoms that carry a warning sign of a possible ongoing infection, even when they appear in isolation The mechanisms that can cause OD have not yet been fully defined. In this context, studies point to several possibilities that can lead to olfactory impairment, such as conductive loss (due to edema in the olfactory cleft), injury to the respiratory epithelium (due to the local inflammatory response with an increase in pro-inflammatory cytokines and chemokines such as IL-6 and IFN-γ), or lesion in the olfactory bulb, with neuronal damage.…”

“…Likewise, other symptoms such as anosmia and augesia can manifest after the end of the infection and can be used as prognostic markers for neuronal diseases. Other manifestations associated with this disease include the increase of migraine or cases of epilepsy; however, the evidence is still unclear because these may occur due to the infection or to the obligatory confinement [ 23 , 26 , 27 ].…”

Neuropsychiatric manifestations of COVID-19: a literature review

“…A pandemia surgiu a partir do SARS-CoV-2, um vírus de RNA responsável pela ocorrência de doença de caráter respiratório. A origem da doença se deu em uma província chinesa, no entanto, a crescente propagação desse patógeno acarretou em um elevado número de mortes e enfermos em âmbito global (DA SILVA JÚNIOR et al, 2022).…”