Tag: long covid neurology

SARS-CoV-2 promotes microglial synapse elimination in human brain organoids

Abstract:

Neuropsychiatric manifestations are common in both the acute and post-acute phase of SARS-CoV-2 infection, but the mechanisms of these effects are unknown. In a newly established brain organoid model with innately developing microglia, we demonstrate that SARS-CoV-2 infection initiate neuronal cell death and cause a loss of post-synaptic termini. Despite limited neurotropism and a decelerating viral replication, we observe a threefold increase in microglial engulfment of postsynaptic termini after SARS-CoV-2 exposure.

We define the microglial responses to SARS-CoV-2 infection by single cell transcriptomic profiling and observe an upregulation of interferon-responsive genes as well as genes promoting migration and synapse engulfment. To a large extent, SARS-CoV-2 exposed microglia adopt a transcriptomic profile overlapping with neurodegenerative disorders that display an early synapse loss as well as an increased incident risk after a SARS-CoV-2 infection. Our results reveal that brain organoids infected with SARS-CoV-2 display disruption in circuit integrity via microglia-mediated synapse elimination and identifies a potential novel mechanism contributing to cognitive impairments in patients recovering from COVID-19.

Source: Samudyata, Oliveira AO, Malwade S, Rufino de Sousa N, Goparaju SK, Gracias J, Orhan F, Steponaviciute L, Schalling M, Sheridan SD, Perlis RH, Rothfuchs AG, Sellgren CM. SARS-CoV-2 promotes microglial synapse elimination in human brain organoids. Mol Psychiatry. 2022 Oct 5:1–12. doi: 10.1038/s41380-022-01786-2. Epub ahead of print. PMID: 36198765; PMCID: PMC9533278.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9533278/ (Full text)

The Psychiatric Consequences of Long-COVID: A Scoping Review

Abstract:

The COVID-19 pandemic has represented a new form of traumatic event, affecting the general population worldwide and causing severe disruption of daily routine. A new urgent concern is related to the burden associated with COVID-19 symptoms that persist beyond the onset of infection, the so-called long-COVID syndrome.
The present paper aims to: (1) describe the most frequent psychiatric symptoms reported by patients affected by long-COVID syndrome; (2) evaluate methodological discrepancies among the available studies; (3) inform clinicians and policy-makers on the possible strategies to be promoted in order to manage the psychiatric consequences of long-COVID syndrome.
Twenty-one papers have been included in the present review, mostly with a cross-sectional or cohort design. Significant heterogeneity of long-COVID syndrome definitions was found. The presence of psychiatric symptoms was evaluated with very different assessment tools.
The most common psychiatric symptoms of the long-COVID syndrome included fatigue, cognitive disturbances/impairment, depression, and anxiety symptoms. The rate of fatigue varied from 93.2–82.3% to 11.5%, cognitive impairment/cognitive dysfunction from 61.4% to 23.5% and depressive-anxiety symptoms from 23.5%to 9.5%
Source: Sampogna G, Di Vincenzo M, Giallonardo V, Perris F, Volpicelli A, Del Vecchio V, Luciano M, Fiorillo A. The Psychiatric Consequences of Long-COVID: A Scoping Review. Journal of Personalized Medicine. 2022; 12(11):1767. https://doi.org/10.3390/jpm12111767  https://www.mdpi.com/2075-4426/12/11/1767/htm (Full text)

Psychiatric and neurological complications of long COVID

Abstract:

COVID-19 was primarily considered a pulmonary disease with extrapulmonary manifestations. As the pandemic spread, there has been growing evidence that the disease affects various organs/systems, including the central and peripheral nervous systems. Accumulation of clinical data demonstrates that in a large population of survivors impairments in the function of one or more organs may persist for a long time, a phenomenon commonly known as post COVID or long COVID.

Fatigue and cognitive dysfunction, such as concentration problems, short-term memory deficits, general memory loss, a specific decline in attention, language and praxis abilities, encoding and verbal fluency, impairment of executive functions, and psychomotor coordination, are amongst the most common and debilitating features of neuropsychatric symptoms of post COVID syndrome. Several patients also suffer from compromised sleep, depression, anxiety and post-traumatic stress disorder. Patients with long COVID may demonstrate brain hypometabolism, hypoperfusion of the cerebral cortex and changes in the brain structure and functional connectivity.

Children and adolescents represent a minority of COVID-19 cases, so not surprisingly data on the long-term sequelae after SARS-CoV-2 infections in these age groups are scarce. Although the pathogenesis, clinical characteristics, epidemiology, and risk factors of the acute phase of COVID-19 have been largely explained, these areas are yet to be explored in long COVID. This review aims to provide an update on what is currently known about long COVID effects on mental health.

Source: Zawilska JB, Kuczyńska K. Psychiatric and neurological complications of long COVID. J Psychiatr Res. 2022 Oct 20;156:349-360. doi: 10.1016/j.jpsychires.2022.10.045. Epub ahead of print. PMID: 36326545; PMCID: PMC9582925. https://www.sciencedirect.com/science/article/pii/S0022395622005982 (Full text)

Brain 18F-FDG PET imaging in outpatients with post-COVID-19 conditions: findings and associations with clinical characteristics

Abstract:

Background: Brain 18F-FDG PET imaging has the potential to provide an objective assessment of brain involvement in post-COVID-19 conditions but previous studies of heterogeneous patient series yield inconsistent results. The current study aimed to investigate brain 18F-FDG PET findings in a homogeneous series of outpatients with post-COVID-19 conditions and to identify associations with clinical patient characteristics.

Methods: We retrospectively included 28 consecutive outpatients who presented with post-COVID-19 conditions between September 2020 and May 2022 and who satisfied the WHO definition, and had a brain 18F-FDG PET for suspected brain involvement but had not been hospitalized for COVID-19. A voxel-based group comparison with 28 age- and sex-matched healthy controls was performed (p-voxel at 0.005 uncorrected, p-cluster at 0.05 FWE corrected) and identified clusters were correlated with clinical characteristics.

Results: Outpatients with post-COVID-19 conditions exhibited diffuse hypometabolism predominantly involving right frontal and temporal lobes including the orbito-frontal cortex and internal temporal areas. Metabolism in these clusters was inversely correlated with the number of symptoms during the initial infection (r = – 0.44, p = 0.02) and with the duration of symptoms (r = – 0.39, p = 0.04). Asthenia and cardiovascular, digestive, and neurological disorders during the acute phase and asthenia and language disorders during the chronic phase (p ≤ 0.04) were associated with these hypometabolic clusters.

Conclusion: Outpatients with post-COVID-19 conditions exhibited extensive hypometabolic right fronto-temporal clusters. Patients with more numerous symptoms during the initial phase and with a longer duration of symptoms were at higher risk of persistent brain involvement.

Source: Goehringer F, Bruyere A, Doyen M, Bevilacqua S, Charmillon A, Heyer S, Verger A. Brain 18F-FDG PET imaging in outpatients with post-COVID-19 conditions: findings and associations with clinical characteristics. Eur J Nucl Med Mol Imaging. 2022 Nov 2. doi: 10.1007/s00259-022-06013-2. Epub ahead of print. PMID: 36322190. https://link.springer.com/article/10.1007/s00259-022-06013-2 (Full text)

Negative correlation between ACE2 gene expression levels and loss of taste in a cohort of COVID-19 hospitalized patients: New clues to long-term cognitive disorders

Abstract:

In early 2020, one of the most prevalent symptoms of SARS-CoV-2 infection was the loss of smell (anosmia), found in 60-70% of all cases. Anosmia used to occur early, concomitantly with other symptoms, and often persisted after recovery for an extended period, sometimes for months. In addition to smell disturbance, COVID-19 has also been associated with loss of taste (ageusia). The latest research suggests that SARS-CoV-2 could spread from the respiratory system to the brain through receptors in sustentacular cells localized to the olfactory epithelium. The virus invades human cells via the obligatory receptor, angiotensin-converting enzyme II (ACE2), and a priming protease, TMPRSS2, facilitating viral penetration. There is an abundant expression of both ACE2 and TMPRSS2 in sustentacular cells.

In this study, we evaluated 102 COVID-19 hospitalized patients, of which 17.60% presented anosmia and 9.80% ageusia. ACE1, ACE2, and TMPRSS2 gene expression levels in nasopharyngeal tissue were obtained by RT-qPCR and measured using ΔCT analysis. ACE1 Alu287bp association was also evaluated. Logistic regression models were generated to estimate the effects of variables on ageusia and anosmia.

Association of ACE2 expression levels with ageusia. was observed (OR: 1.35; 95% CI: 1.098-1.775); however, no association was observed between TMPRSS2 and ACE1 expression levels and ageusia. No association was observed among the three genes and anosmia, and the Alu287bp polymorphism was not associated with any of the outcomes.

Lastly, we discuss whetherthere is a bridge linking these initial symptoms, including molecular factors, to long-term COVID-19 health consequences such as cognitive dysfunctions.

Source: Braga-Paz I, Ferreira de Araújo JL, Alves HJ, de Ávila RE, Resende GG, Teixeira MM, de Aguiar RS, de Souza RP, Bahia D. Negative correlation between ACE2 gene expression levels and loss of taste in a cohort of COVID-19 hospitalized patients: New clues to long-term cognitive disorders. Front Cell Infect Microbiol. 2022 Sep 29;12:905757. doi: 10.3389/fcimb.2022.905757. PMID: 36250059; PMCID: PMC9556632. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9556632/ (Full text)

Headaches and Dizziness as Disabling, Persistent Symptoms in Patients with Long COVID-A National Multicentre Study

Abstract:

Background: Currently, about 15% of coronavirus disease-19 (COVID-19) patients are affected by Long COVID worldwide; however, this condition has not yet been sufficiently studied. The aim of this study was to identify the impact of symptom persistence as well as clinical and socio-demographic variables in a cohort of people with Long COVID.

Methods: We conducted a descriptive cross-sectional study of a sample of adult patients from different Spanish regions presenting with Long COVID. Data collection was conducted between April and July 2021. Functional status and dependency were assessed.

Results: A multivariate linear regression was performed, and the model was statistically significant (F (7; 114) = 8.79; p < 0.001), according to the overall ALDQ score. The variables with a statistically significant effect on the degree of dependence were age (p = 0.014), time since diagnosis (p = 0.02), headaches (p = 0.031), and dizziness (p = 0.039). Functional status post-COVID showed a positive and significant relationship with the percentage of dependence (p < 0.001).

Conclusions: People affected by Long COVID showed moderate dependency status and limitations in functionality. Those with neurological symptoms, such as dizziness and headaches, as well as older age, showed a higher degree of dependency. Improvements in dependency status occurred with increasing time since diagnosis.

Source: Rodríguez-Pérez MP, Sánchez-Herrera-Baeza P, Rodríguez-Ledo P, Serrada-Tejeda S, García-Bravo C, Pérez-de-Heredia-Torres M. Headaches and Dizziness as Disabling, Persistent Symptoms in Patients with Long COVID-A National Multicentre Study. J Clin Med. 2022 Oct 6;11(19):5904. doi: 10.3390/jcm11195904. PMID: 36233769; PMCID: PMC9572453. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9572453/ (Full text)

SARS-CoV-2, long COVID, prion disease and neurodegeneration

Introduction:

On the last day of the year 2019 a novel Betacoronavirus (2019-nCov), now known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and causing the highly transmissible and lethal pneumonia COVID-19 was first reported in Wuhan, Hubei Province in Central China (Huang et al., ; Fu et al., ; Lu and Sun, ). Since then ongoing research and long-term studies of the sequelae of SARS-CoV-2 infection have indicated that post-infection, recovery from COVID-19 and/or COVID-19 aftermath is associated with long-term physiological and neurological deficits known generically as “long COVID” (Roy et al., ; Ahmad et al., ; Baazaoui and Iqbal, ). Multiple independent epidemiological and clinical studies further indicate that SARS-CoV-2 infection and “long COVID” strongly correlate with the onset of progressive neurological disturbances that include Alzheimer’s disease (AD), prion disease (PrD) and other neurodegenerative disorders. These are apparent: (i) especially in aged and/or senile COVID-19 patients; (ii) in patients experiencing overlapping or inter-current illnesses that include heart disease, diabetes, hypertension, neuropsychiatric and other age-related neurological disorders; and (iii) in those COVID-19 patients who have experienced a particularly virulent and/or a near fatal episode of SARS-CoV-2 infection (Farheen et al., ; Flud et al., ; Fu et al., ). Conversely, increasing numbers of epidemiological studies suggest that elderly people with neurological deficits commonly observed in AD are highly vulnerable to SARS-CoV-2 infection, and especially the development of more severe forms of COVID-19 disease (Chiricosta et al., ; Hsu et al., ; Fu et al., ). The recent finding that the SARS-CoV-2 “S1” spike protein essential for viral infectivity contains prion-like domains associated with immune-evasion and the promotion of protein aggregation and aggregate “seeding” is particularly intriguing (Baazaoui and Iqbal, ; Bernardini et al., ; Tetz and Tetz, ). Based on these and other very recent findings this “Opinion” paper will: (i) address our current understanding of the emerging role of SARS-CoV-2 infection with “long COVID” with special reference to AD and PrD; (ii) will review the latest findings of the SARS-CoV-2 “S1” spike protein and its preferred interaction with the ubiquitous angiotensin converting enzyme-2 (ACE2) receptor (ACE2R); and (iii) will highlight the interplay of the molecular biology and neuropathology of SARS-CoV-2 with the unusual and immune-evasive character of prion neurobiology, AD and PrD.

Read the rest of this article HERE.

Source: Zhao Y, Jaber VR, Lukiw WJ. SARS-CoV-2, long COVID, prion disease and neurodegeneration. Front Neurosci. 2022 Sep 27;16:1002770. doi: 10.3389/fnins.2022.1002770. PMID: 36238082; PMCID: PMC9551214.  Zhao Y, Jaber VR, Lukiw WJ. SARS-CoV-2, long COVID, prion disease and neurodegeneration. Front Neurosci. 2022 Sep 27;16:1002770. doi: 10.3389/fnins.2022.1002770. PMID: 36238082; PMCID: PMC9551214. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9551214/ (Full text)

Even mild COVID-19 may have long-term brain impacts

Research presented at the Alzheimer’s Association International Conference suggests even mild cases of COVID-19 may be associated with cognitive deficits months after recovery.

One Argentinian study of 234 seniors who previously had COVID-19 found that more than half showed some degree of cognitive impairment months later. One in three had severe “dementia-like” impairments in memory, attention and executive function — a much higher proportion than the 5%–8% of seniors in the general population who have dementia at a given time.

“This could be the start of a dementia-related epidemic fueled by this latest coronavirus,” stated presenting author Dr. Gabriel de Erausquin of the Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases at UT Health San Antonio. Researchers will follow the study participants over the next three to five years to see if these problems resolve or worsen.

The study didn’t look at participants’ cognitive performance prior to infection. However, those who lost their sense of smell while sick with COVID-19 tended to have more severe cognitive impairments months later, even if their other symptoms had been mild. According to de Erausquin, “once the virus has affected the olfactory bulb and caused effects there — changes that we can see with imaging — then other places in the brain that are connected to it also become abnormal, either in function or structure or both.”

Other research presented linked SARS-CoV-2 infection with an uptick in biomarkers of brain injury, neuroinflammation and Alzheimer disease. One American study of 310 patients with COVID-19 found that those with new neurological symptoms had higher levels of t-tau, NfL, GFAP, pTau-181, and UCH-L1 in their blood, as well as indicators of inflammation such as C-reactive protein, compared to patients without neurological symptoms. “These findings suggest patients who had COVID-19 may have an acceleration of Alzheimer-related symptoms and pathology,” according to presenting author Dr. Thomas Wisniewski of the New York University Grossman School of Medicine.

Earlier this year, de Erausquin and others reported that brain inflammation, stroke and other common complications of viral infections have longstanding links with neurodegenerative disorders. “Therefore, it seems likely to expect that COVID-19-related cardiovascular and cerebrovascular disease will also contribute to a higher longterm risk of cognitive decline and dementia in recovered individuals.”

Several recent studies have documented cognitive deficits post-COVID but like the research presented at the Alzheimer’s Association conference, data on patients’ performance before infection are lacking.

One British study of 81 337 people in EClinicalMedicine found that those who previously had COVID-19 tended to score lower on measures of intelligence, reasoning, problem-solving and planning than people who were never infected.

“These results accord with reports of long-COVID, where ‘brain fog,’ trouble concentrating and difficulty finding the correct words are common,” according to the authors. People who had been hospitalized and put on ventilators had the greatest impairments, but even those who had relatively mild symptoms showed some deficit.

In another study of 57 Americans receiving inpatient rehabilitation after hospitalization for COVID-19, four in five had mild to severe cognitive impairments. More than half had deficits in working memory, while two in five had impaired processing speed, divided attention, and trouble switching between mental tasks.

Similar deficits have also been noted in patients after recovery from other coronaviruses. A 2020 systematic review and meta-analysis found that delirium was common in the acute stage of severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and COVID-19. Following up with patients six weeks to 39 months later, more than 15% reported sleep disorders, mood swings, trouble concentrating, impaired memory and other mental challenges.

Based on this growing body of evidence, British researchers warned in March that health systems will likely see an “influx of patients with psychiatric and cognitive problems who were otherwise healthy prior to COVID-19.” They urged doctors to consider detailed cognitive evaluations for anyone reporting new neurological symptoms after infection with SARS-CoV-2.

In the meantime, the Alzheimer’s Association has formed an international consortium to study the long-term effects of COVID-19 on the brain.

“These new data point to disturbing trends showing COVID-19 infections leading to lasting cognitive impairment and even Alzheimer’s symptoms,” stated Heather Snyder of the Alzheimer’s Association. “It is imperative that we continue to study what this virus is doing to our bodies and brains.”

Source: Duong D. Even mild COVID-19 may have long-term brain impacts. CMAJ. 2021 Aug 30;193(34):E1360-E1361. doi: 10.1503/cmaj.1095958. PMID: 34462298; PMCID: PMC8432319.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8432319/ (Full text)

The Neurobiology of Long COVID

Abstract:

Persistent neurological and neuropsychiatric symptoms affect a substantial fraction of people after COVID-19 and represent a major component of the post-acute COVID syndrome, also known as long COVID. Here, we review what is understood about the pathobiology of post-acute COVID-19 impacts on the CNS and discuss possible neurobiological underpinnings of the cognitive symptoms affecting COVID-19 survivors. We propose the chief mechanisms that may contribute to this emerging neurological health crisis.
Source: Michelle Monje, Akiko Iwasaki. The Neurobiology of Long COVID. Published:October 06, 2022. DOI: https://doi.org/10.1016/j.neuron.2022.10.006 https://www.cell.com/neuron/pdf/S0896-6273(22)00910-2.pdf (Full text available as PDF file)

Neurological post-acute sequelae of SARS-CoV-2 infection (PASC)

Abstract:

The novel corona virus infectious disease, COVID-19, caused by SARS-CoV-2, can have two phases: acute (generally 4 weeks after onset) and chronic (> 4 weeks after onset). Both phases include a wide variety of signs and symptoms including neurological and psychiatric symptoms. The signs and symptoms that are considered sequelae of COVID-19 are termed post-COVID condition, long COVID-19, and post-acute sequelae of SARS-CoV-2 infection (PASC).

PASC symptoms include fatigue, dyspnea, palpitation, dysosmia, sub-fever, hypertension, alopecia, sleep problems, loss of concentration, amnesia, numbness, pain, gastrointestinal symptoms, depression, and anxiety. Because the specific pathophysiology of PASC has not yet been clarified, there are no definite criteria of the condition, hence the World Health Organization’s definition is quite broad. Consequently, it is difficult to correctly diagnose PASC.

Approximately 50% of patients may show at least one PASC symptom up to 12 months after COVID-19 infection; however, the exact prevalence of PASC has not been determined. Despite extensive research in progress worldwide, there are currently no clear diagnostic methodologies or treatments for PASC.

In this review, we discuss the currently available information on PASC and highlight the neurological sequelae of COVID-19 infection. Furthermore, we provide clinical suggestions for diagnosing and caring for PASC patients based on our outpatient clinic experience.

Source: Takao M, Ohira M. Neurological post-acute sequelae of SARS-CoV-2 infection (PASC). Psychiatry Clin Neurosci. 2022 Sep 23. doi: 10.1111/pcn.13481. Epub ahead of print. PMID: 36148558. https://pubmed.ncbi.nlm.nih.gov/36148558/