Tag: long Covid

Brain disorders: Impact of mild SARS-CoV-2 may shrink several parts of the brain

Abstract:

Coronavirus (COVID-19) is a highly infectious respiratory infection discovered in Wuhan, China, in December 2019. As a result of the pandemic, several individuals have experienced life-threatening diseases, the loss of loved ones, lockdowns, isolation, an increase in unemployment, and household conflict. Moreover, COVID-19 may cause direct brain injury via encephalopathy. The long-term impacts of this virus on mental health and brain function need to be analysed by researchers in the coming years.

This article aims to describe the prolonged neurological clinical consequences related to brain changes in people with mild COVID-19 infection. When compared to a control group, people those who tested positive for COVID-19 had more brain shrinkage, grey matter shrinkage, and tissue damage. The damage occurs predominantly in areas of the brain that are associated with odour, ambiguity, strokes, reduced attention, headaches, sensory abnormalities, depression, and mental abilities for few months after the first infection. Therefore, in patients after a severe clinical condition of COVID-19, a deepening of persistent neurological signs is necessary.

Source: Kumar PR, Shilpa B, Jha RK. Brain Disorders: Impact of Mild SARS-CoV-2 May Shrink Several Parts of the Brain. Neurosci Biobehav Rev. 2023 Mar 31;149:105150. doi: 10.1016/j.neubiorev.2023.105150. Epub ahead of print. PMID: 37004892; PMCID: PMC10063523. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10063523/ (Full text)

Long-COVID fatigue is not predicted by pre-pandemic plasma IL-6 levels in mild COVID-19 infection

Abstract:

Objective and design: Fatigue is a prominent symptom in the general population and may follow viral infection, including SARS-CoV2 infection which causes COVID-19. Chronic fatigue lasting more than three months is a major symptom of the long-COVID syndrome. The mechanisms underlying long-COVID fatigue are unknown. We hypothesized that the development of long-COVID chronic fatigue is driven by the pro-inflammatory immune status of an individual prior to COVID-19 infection.

Subjects and methods: We tested this hypothesis by analysing pre-pandemic plasma levels of IL-6, which plays a key role in persistent fatigue, in N = 1274 community dwelling adults from TwinsUK. Subsequent COVID-19 positive and COVID-19 negative participants were categorized based on antigen and antibody testing. Chronic fatigue was assessed using the Chalder Fatigue Scale.

Results: COVID-19 positive participants exhibited mild symptoms of infection. Chronic fatigue was a prevalent symptom among this population and was significantly higher in the COVID-19 positive participants than COVID-19 negative participants (17% vs 11%, respectively; p = 0.001). The qualitative nature of chronic fatigue as determined by individual questionnaire responses was similar in COVID-19 positive and COVID-19 negative participants. Pre-pandemic plasma IL-6 levels were positively associated with chronic fatigue in COVID-19 negative, but not COVID-19 positive
individuals. Raised BMI was associated with chronic fatigue in COVID-19 positive participants.

Conclusions: We found evidence that pre-existing increased levels of IL-6 provide the ground for chronic fatigue symptoms but there was no specific link seen with mild COVID-19 status. Elevated BMI increased the risk of chronic fatigue in mild COVID-19 infection consistent with previous reports.

Source: B Freidin, M., Borsini, A., Pariante, C., & MK Williams, F. (2023). Long-COVID fatigue is not predicted by prepandemic plasma IL-6 levels in mild COVID-19 infection. Inflammation Research. https://kclpure.kcl.ac.uk/portal/files/201594849/Freidin_et_al._2023.pdf (Full text)

Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses

Abstract:

We measured brain injury markers, inflammatory mediators, and autoantibodies in 203 participants with COVID-19; 111 provided acute sera (1-11 days post admission) and 56 with COVID-19-associated neurological diagnoses provided subacute/convalescent sera (6-76 weeks post-admission).

Compared to 60 controls, brain injury biomarkers (Tau, GFAP, NfL, UCH-L1) were increased in acute sera, significantly more so for NfL and UCH-L1, in patients with altered consciousness. Tau and NfL remained elevated in convalescent sera, particularly following cerebrovascular and neuroinflammatory disorders. Acutely, inflammatory mediators (including IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) were higher in participants with altered consciousness, and correlated with brain injury biomarker levels. Inflammatory mediators were lower than acute levels in convalescent sera, but levels of CCL2, CCL7, IL-1RA, IL-2Rα, M-CSF, SCF, IL-16 and IL-18 in individual participants correlated with Tau levels even at this late time point.

When compared to acute COVID-19 patients with a normal GCS, network analysis showed significantly altered immune responses in patients with acute alteration of consciousness, and in convalescent patients who had suffered an acute neurological complication. The frequency and range of autoantibodies did not associate with neurological disorders. However, autoantibodies against specific antigens were more frequent in patients with altered consciousness in the acute phase (including MYL7, UCH-L1, GRIN3B, and DDR2), and in patients with neurological complications in the convalescent phase (including MYL7, GNRHR, and HLA antigens).

In a novel low-inoculum mouse model of SARS-CoV-2, while viral replication was only consistently seen in mouse lungs, inflammatory responses were seen in both brain and lungs, with significant increases in CCL4, IFNγ, IL-17A, and microglial reactivity in the brain. Neurological injury is common in the acute phase and persists late after COVID-19, and may be driven by a para-infectious process involving a dysregulated host response.

Source: Benedict D. Michael, Cordelia Dunai, Edward J. Needham, Kukatharmini Tharmaratnam, Robyn Williams, Yun Huang, Sarah A. Boardman, Jordan Clark, Parul Sharma, Krishanthi Subramaniam, Greta K. Wood, Ceryce Collie, Richard Digby, Alexander Ren, Emma Norton, Maya Leibowitz, Soraya Ebrahimi, Andrew Fower, Hannah Fox, Esteban Tato, Mark Ellul, Geraint Sunderland, Marie Held, Claire Hetherington, Franklyn Nkongho, Alish Palmos, Alexander Grundmann, James P. Stewart, Michael Griffiths, Tom Solomon, Gerome Breen, Alasdair Coles, Jonathan Cavanagh, Sarosh R. Irani, Angela Vincent, Leonie Taams, David K. Menon. Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses. medRxiv 2023.04.03.23287902; doi: https://doi.org/10.1101/2023.04.03.23287902 (Full text available as PDF file)

Case Study: COVID-19 Brain Fog or Auditory Processing Disorder?

A wide array of symptoms have been directly associated with COVID-19 following recovery, but they can also occur several weeks or months after the diagnosis. These include, but are not limited to, damage to the respiratory tract as well as decreased cognition and other brain functions. The nonmedical term used to describe these post-COVID-19 problems is “brain fog.”

The symptoms of brain fog are similar to mild cognitive impairment or, of interest to audiologists, an auditory processing disorder (APD). 2 COVID-19 has neurological consequences and affects specific areas of the brain, such as the cingulate cortex (i.e. emotions, memory, depression, and decision of action). 3 Brain fog is also associated with several symptoms related to hearing and communication, which can affect the accomplishment of routine daily tasks. Many of those can be mistaken for or coexist with APD symptoms. These include “difficulty attending or staying focused, difficulty concentrating, difficulty understanding or remembering instructions, language problems, short-term memory problems,” to mention a few. 2 However, what might appear as a brain fog case could be an undiagnosed or even a pre-existing APD issue. 2 Symptoms could include struggling to keep track of conversations, forgetfulness and memory issues, problems following directions, and several cognitive difficulties. 2

This report presents the case of a 31-year-old medical doctor who was diagnosed with COVID-19 in December 2020, and later identified with APD symptoms that are now commonly seen in post-COVID-19 brain fog patients. Auditory training following the Buffalo Model 4 resolved the patient’s chief complaints following 12 treatment sessions. This issue is one of many that could shed light on the great potential auditory training has in resolving brain fog complaints that overlap with what is commonly seen in APD patients, highlighting the concerns regarding COVID-19’s direct effects on auditory processing.

Source: Alexander, Angela Loucks AuD, MNZAS, CCC-A; DiSogra, Robert M. AuD; Abbas, Fatima BS; Braund, Stacey AuD, CCC-A; Spokes, Chelsea BSpHLSc, MClinAud. Case Study: COVID-19 Brain Fog or Auditory Processing Disorder?. The Hearing Journal 76(04):p 18,19,20,22,23,24, April 2023. | DOI: 10.1097/01.HJ.0000927332.17564.4e https://journals.lww.com/thehearingjournal/Fulltext/2023/04000/Case_Study__COVID_19_Brain_Fog_or_Auditory.2.aspx (Full text)

Incident autoimmune diseases in association with a SARS-CoV-2 infection: A matched cohort study

Abstract:

Objectives To investigate whether the risk of developing an incident autoimmune disease is increased in patients with previous COVID-19 disease compared to people without COVID-19.

Method A cohort was selected from German routine health care data covering 38.9 million individuals. Based on documented diagnoses, we identified individuals with polymerase chain reaction (PCR)-confirmed COVID-19 through December 31, 2020. Patients were matched 1:3 to control patients without COVID-19. Both groups were followed up until June 30, 2021. We used the four quarters preceding the index date until the end of follow-up to analyze the onset of autoimmune diseases during the post-acute period. Incidence rates (IR) per 1000 person-years were calculated for each outcome and patient group. Poisson models were deployed to estimate the incidence rate ratios (IRRs) of developing an autoimmune disease conditional on a preceding diagnosis of COVID-19.

Results In total, 641,704 patients with COVID-19 were included. Comparing the incidence rates in the COVID-19 (IR=15.05, 95% CI: 14.69-15.42) and matched control groups (IR=10.55, 95% CI: 10.25-10.86), we found a 42.63% higher likelihood of acquiring autoimmunity for patients who had suffered from COVID-19. This estimate was similar for common autoimmune diseases, such as Hashimoto thyroiditis, rheumatoid arthritis, or Sjögren syndrome. The highest IRR was observed for autoimmune disease of the vasculitis group. Patients with a more severe course of COVID-19 were at a greater risk for incident autoimmune diseases.

Conclusions SARS-CoV-2 infection is associated with an increased risk of developing new-onset autoimmune diseases after the acute phase of infection.

Source: Falko Tesch, Franz Ehm, Annika Vivirito, Danny Wende, Manuel Batram, Friedrich Loser, Simone Menzer, Josephine Jacob, Martin Roessler, Martin Seifert, Barbara Kind, Christina König, Claudia Schulte, Tilo Buschmann, Dagmar Hertle, Pedro Ballesteros, Stefan Baßler, Barbara Bertele, Thomas Bitterer, Cordula Riederer, Franziska Sobik, Lukas Reitzle, Christa Scheidt-Nave, Jochen Schmitt. Incident autoimmune diseases in association with a SARS-CoV-2 infection: A matched cohort study. medRxiv 2023.01.25.23285014; doi:https://doi.org/10.1101/2023.01.25.23285014 (Full text)

Chronic cough in post-COVID syndrome: Laryngeal electromyography findings in vagus nerve neuropathy

Abstract:

Background: Despite being a new entity, there is a large amount of information on the characteristics of SARS-CoV-2 infection and the symptoms of the acute phase; however, there are still many unknowns about the clinical features and pathophysiology of post-COVID syndrome. Refractory chronic cough is one of the most prevalent symptoms and carries both a medical problem and a social stigma. Many recent studies have highlighted the role of SARS-CoV-2 neurotropism, but no studies have demonstrated vagus nerve neuropathy as a cause of persistent chronic cough or other COVID-19 long-term effects.

Objective: The main objective was to assess the involvement of the vagus nerve neuropathy as a cause of chronic cough and other post-COVID syndrome symptoms.

Material and methods: This was a single-center observational study with prospective clinical data collected from 38 patients with chronic cough and post-COVID-19 syndrome. Clinical characteristics and laryngeal electromyographic findings were analyzed.

Results: Clinical data from 38 patients with chronic cough after 12 weeks of the acute phase of COVID-19 infection were analyzed. Of these patients, 81.6% suffered from other post-COVID conditions and, 73.6% reported fluctuating evolution of symptoms. Laryngeal electromyography (LEMG) of the thyroarytenoid (TA) muscles and cricothyroid (CT) muscles was pathological in 76.3% of the patients. Of the patients with abnormal LEMG, chronic denervation was the most frequent finding (82.8%), 10.3% presented acute denervation signs, and 6.9% presented myopathic pattern in LEMG.

Conclusions: LEMG studies suggest the existence of postviral vagus nerve neuropathy after SARS-CoV-2 infection that could explain chronic cough in post-COVID syndrome.

Source: García-Vicente P, Rodríguez-Valiente A, Górriz Gil C, Márquez Altemir R, Martínez-Pérez F, López-Pajaro LF, et al. (2023) Chronic cough in post-COVID syndrome: Laryngeal electromyography findings in vagus nerve neuropathy. PLoS ONE 18(3): e0283758. https://doi.org/10.1371/journal.pone.0283758 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0283758 (Full text)

Neurocognitive and psychiatric symptoms following infection with COVID-19: Evidence from laboratory and population studies

Abstract:

Objective: The objective of the current investigation was to examine associations between symptomatic COVID-19 history, neurocognitive function, and psychiatric symptoms using cognitive task performance, functional brain imaging, and a prospective population survey.

Methods: Study 1 was a laboratory study conducted between 3 May 2022 and 16 Nov 2022 involving 120 fully vaccinated community dwelling adults between 18 and 84 years of age (Mage = 31.96 (SD = 20.71), 63.3% female). In this cross-sectional study we examined the association between symptomatic COVID-19 infection history and performance on three computer tasks assessing cognitive function (Flanker interference, delay discounting and simple reaction time) and measured oxygen saturation within the prefrontal cortex using functional near infrared spectroscopy (fNIRS). Study 2 was a 2-wave population survey undertaken between 28 September 2021 and 21 March 2022, examining the prospective relationship between symptomatic COVID-19 and self-reported symptoms of cognitive dysfunction, depressive symptoms, anxiety symptoms, and agitation at 6-month follow up. The sample (N = 2,002, M age = 37.0, SD = 10.4; 60.8% female) was collected using a quota process to ensure equal numbers of vaccinated and unvaccinated individuals. Structural equation modelling with latent variables was performed on the population-level data, evaluating the fit of the proposed mediational model of symptomatic COVID-19 to psychiatric symptoms through cognitive dysfunction.

Results: Findings from Study 1 revealed significant effects of symptomatic COVID-19 history on Flanker interference and delay discounting. Effects on flanker performance were significantly stronger among older adult women (effect: 9.603, SE = 4.452, t = 2.157, p = .033), and were accompanied by task-related changes cerebral oxygenation at the right superior frontal gyrus (F (1, 143.1) = 4.729, p = .031). Additionally, those with a symptomatic COVID-19 infection history showed evidence of amplified delay discounting (coefficient = 0.4554, SE = 0.2208, t = 2.0629, p = .041). In Study 2, baseline symptomatic COVID-19 history was associated with self-reported cognitive dysfunction and a latent variable reflecting psychiatric symptoms of anxiety, depression and agitation at follow-up. Mediational analyses revealed evidence of cognitive mediation of clinically significant psychiatric outcomes: depression (indirect effect = 0.077, SE = 0.026, p = .003) and generalized anxiety (indirect effect = 0.060, SE = 0.021, p = .004).

Conclusions: Converging findings from laboratory and population survey data support the conclusion that symptomatic COVID-19 infection is associated with task-related, functional imaging and self-reported indices of cognitive dysfunction as well as psychiatric symptoms. In some cases, these findings appear to be more amplified among women than men, and among older women than younger.

Source: Hall PA, Ayaz H, Meng G, Hudson A, Sakib MN, Quah ACK, Agar TK, Lee JA, Boudreau C, Fong GT. Neurocognitive and psychiatric symptoms following infection with COVID-19: Evidence from laboratory and population studies. Brain Behav Immun Health. 2023 Mar;28:100595. doi: 10.1016/j.bbih.2023.100595. Epub 2023 Jan 24. PMID: 36713476; PMCID: PMC9870612. https://www.sciencedirect.com/science/article/pii/S2666354623000091?via%3Dihub (Full study)

The original strain of SARS-CoV-2, the Delta variant, and the Omicron variant infect microglia efficiently, in contrast to their inability to infect neurons: Analysis using 2D and 3D cultures

Highlights:

  • None of the SARS-CoV-2 original, delta, or omicron strains can infect neurons.
  • The SARS-CoV-2 original, delta, and omicron strains can infect microglia.
  • The CNS cells differentiated from hiPSCs are useful to investigate the infectivity of the virus.

Abstract:

COVID-19 causes neurological damage, systemic inflammation, and immune cell abnormalities. COVID-19-induced neurological impairment may be caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which directly infects cells of the central nervous system (CNS) and exerts toxic effects. Furthermore, SARS-CoV-2 mutations occur constantly, and it is not well understood how the infectivity of the virus to cells of the CNS changes as the virus mutates.

Few studies have examined whether the infectivity of cells of CNS – neural stem/progenitor cells (NS/PCs), neurons, astrocytes, and microglia – varies among SARS-CoV-2 mutant strains. In this study, therefore, we investigated whether SARS-CoV-2 mutations increase infectivity to CNS cells, including microglia.

Since it was essential to demonstrate the infectivity of the virus to CNS cells in vitro using human cells, we generated cortical neurons, astrocytes, and microglia from human induced pluripotent stem cells (hiPSCs). We added pseudotyped lentiviruses of SARS-CoV-2 to each type of cells, and then we examined their infectivity. We prepared three pseudotyped lentiviruses expressing the S protein of the original strain (the first SARS-CoV-2 discovered in the world), the Delta variant, and the Omicron variant on their envelopes and analyzed differences of their ability to infect CNS cells. We also generated brain organoids and investigated the infectivity of each virus.

The viruses did not infect cortical neurons, astrocytes, or NS/PCs, but microglia were infected by the original, Delta, and Omicron pseudotyped viruses. In addition, DPP4 and CD147, potential core receptors of SARS-CoV-2, were highly expressed in the infected microglia, while DPP4 expression was deficient in cortical neurons, astrocytes, and NS/PCs.

Our results suggest that DPP4, which is also a receptor for Middle East respiratory syndrome-coronavirus (MERS-CoV), may play an essential role in the CNS. Our study is applicable to the validation of the infectivity of viruses that cause various infectious diseases in CNS cells, which are difficult to sample from humans.

Source: Kase Y, Sonn I, Goto M, Murakami R, Sato T, Okano H. The original strain of SARS-CoV-2, the Delta variant, and the Omicron variant infect microglia efficiently, in contrast to their inability to infect neurons: Analysis using 2D and 3D cultures. Exp Neurol. 2023 Mar 11;363:114379. doi: 10.1016/j.expneurol.2023.114379. Epub ahead of print. PMID: 36914084; PMCID: PMC10008041. https://www.sciencedirect.com/science/article/pii/S0014488623000638?via%3Dihub (Full text)

Potential Prion Involvement in Long COVID-19 Neuropathology, Including Behavior

Abstract:

Prion is a term used to describe a protein infectious particle responsible for several neurodegenerative diseases in mammals, e.g., Creutzfeldt-Jakob disease. The novelty is that it is protein based infectious agent not involving a nucleic acid genome as found in viruses and bacteria.

Prion disorders exhibit, in part, incubation periods, neuronal loss, and induce abnormal folding of specific normal cellular proteins due to enhancing reactive oxygen species associated with mitochondria energy metabolism. These agents may also induce memory, personality and movement abnormalities as well as depression, confusion and disorientation.

Interestingly, some of these behavioral changes also occur in COVID-19 and mechanistically include mitochondrial damage caused by SARS-CoV-2 and subsequent production of reactive oxygen species. Taken together, we surmise, in part, long COVID may involve the induction of spontaneous prion emergence, especially in individuals susceptible to its origin may thus explain some of its manisfestions post-acute viral infection.

Source: Stefano GB, Büttiker P, Weissenberger S, Anders M, Raboch J, Ptacek R, Kream RM. Potential Prion Involvement in Long COVID-19 Neuropathology, Including Behavior. Cell Mol Neurobiol. 2023 Mar 28:1–6. doi: 10.1007/s10571-023-01342-8. Epub ahead of print. PMID: 36977809; PMCID: PMC10047479. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10047479/ (Full text)

Association of Laparoscopically-confirmed Endometriosis with Long COVID: A Prospective Cohort Study

Abstract:

Background: Women are at greater risk than men of developing chronic inflammatory conditions and of developing ‘long COVID.’ However, few gynecologic health risk factors for long COVID have been identified. Endometriosis is a common gynecological disorder associated with chronic inflammation, immune dysregulation, and comorbid presentation with autoimmune and clotting disorders, all of which are pathophysiologic mechanisms proposed for long COVID. Therefore, we hypothesized that women with a history of endometriosis may be at greater risk of developing long COVID.

Objective: To investigate the association between history of endometriosis prior to SARS-CoV-2 infection and risk of long COVID.

Methods: We followed 46,579 women from two ongoing prospective cohort studies: the Nurses’ Health Study II and the Nurses’ Health Study 3, who participated in a series of COVID-19-related surveys administered from April 2020 to November 2022. Laparoscopic diagnosis of endometriosis was documented prospectively in main cohort questionnaires prior to the pandemic (1993-2020) with high validity. SARS-CoV-2 infection (confirmed by antigen, PCR, or antibody test) and CDC-defined long-term COVID-19 symptoms (≥4 weeks) were self-reported during follow-up. Among individuals with SARS-CoV-2 infection, we fit Poisson regression models to assess the associations between endometriosis and risk of long COVID-19 symptoms, with adjustment for potential confounding variables (demographics, body mass index, smoking status, history of infertility, and history of chronic diseases).

Results: Among 3650 women in our sample with self-reported SARS-CoV-2 infections during follow-up, 386 (10.6%) had a history of endometriosis with laparoscopic confirmation and 1598 (43.8%) reported experiencing long COVID symptoms. The majority of women were Non-Hispanic White (95.4%), with a median age of 59 years (interquartile range=44-65). Women with a history of laparoscopically-confirmed endometriosis had a 22% greater risk of developing long COVID (adjusted RR=1.22, 95% CI=1.05-1.42), compared to those who had never been diagnosed with endometriosis. The association was stronger when we defined long COVID as having symptoms ≥8 weeks (RR=1.28, 95% CI=1.09-1.50). We observed no statistically significant differences in the relationship between endometriosis and long COVID by age, infertility history, or comorbidity with uterine fibroids, although there was a suggestive trend that women <50 years may be at higher risk (<50 years, RR=1.37, 95% CI=1.00-1.88; ≥50 years, RR=1.19, 95% CI=1.01-1.41). Among persons who developed long COVID, women with endometriosis reported on average one additional long-term symptom compared to women without endometriosis.

Conclusions and relevance: Our findings suggest that those with a history of endometriosis may be at modestly increased risk for long COVID. Health care providers should be aware of endometriosis history when treating patients for signs of persisting symptoms post-SARS-CoV-2 infection. Future studies should investigate the potential biological pathways underlying these associations.

Source: Wang S, Farland LV, Gaskins AJ, Mortazavi J, Wang YX, Tamimi RM, Rich-Edwards JW, Zhang D, Terry KL, Chavarro JE, Missmer SA. Association of Laparoscopically-confirmed Endometriosis with Long COVID: A Prospective Cohort Study. Am J Obstet Gynecol. 2023 Mar 25:S0002-9378(23)00177-1. doi: 10.1016/j.ajog.2023.03.030. Epub ahead of print. PMID: 36972892. https://pubmed.ncbi.nlm.nih.gov/36972892/ https://www.ajog.org/article/S0002-9378(23)00177-1/pdf (Full text available as PDF file)