Tag: 2022

Pathophysiological mechanisms of thrombosis in acute and long COVID-19

Abstract:

COVID-19 patients have a high incidence of thrombosis, and thromboembolic complications are associated with severe COVID-19 and high mortality. COVID-19 disease is associated with a hyper-inflammatory response (cytokine storm) mediated by the immune system. However, the role of the inflammatory response in thrombosis remains incompletely understood.

In this review, we investigate the crosstalk between inflammation and thrombosis in the context of COVID-19, focusing on the contributions of inflammation to the pathogenesis of thrombosis, and propose combined use of anti-inflammatory and anticoagulant therapeutics. Under inflammatory conditions, the interactions between neutrophils and platelets, platelet activation, monocyte tissue factor expression, microparticle release, and phosphatidylserine (PS) externalization as well as complement activation are collectively involved in immune-thrombosis. Inflammation results in the activation and apoptosis of blood cells, leading to microparticle release and PS externalization on blood cells and microparticles, which significantly enhances the catalytic efficiency of the tenase and prothrombinase complexes, and promotes thrombin-mediated fibrin generation and local blood clot formation.

Given the risk of thrombosis in the COVID-19, the importance of antithrombotic therapies has been generally recognized, but certain deficiencies and treatment gaps in remain. Antiplatelet drugs are not in combination with anticoagulant treatments, thus fail to dampen platelet procoagulant activity. Current treatments also do not propose an optimal time for anticoagulation. The efficacy of anticoagulant treatments depends on the time of therapy initiation. The best time for antithrombotic therapy is as early as possible after diagnosis, ideally in the early stage of the disease.

We also elaborate on the possible mechanisms of long COVID thromboembolic complications, including persistent inflammation, endothelial injury and dysfunction, and coagulation abnormalities. The above-mentioned contents provide therapeutic strategies for COVID-19 patients and further improve patient outcomes.

Source: Jing H, Wu X, Xiang M, Liu L, Novakovic VA, Shi J. Pathophysiological mechanisms of thrombosis in acute and long COVID-19. Front Immunol. 2022 Nov 16;13:992384. doi: 10.3389/fimmu.2022.992384. PMID: 36466841; PMCID: PMC9709252. https://www.frontiersin.org/articles/10.3389/fimmu.2022.992384/full (Full text)

Psychological consequences of long COVID: comparing trajectories of depressive and anxiety symptoms before and after contracting SARS-CoV-2 between matched long- and short-COVID groups

Abstract:

Background: There is a growing global awareness of the psychological consequences of long COVID, supported by emerging empirical evidence. However, the emergence and long-term trajectories of psychological symptoms following the infection are still unclear.

Aims: To examine when psychological symptoms first emerge following infection with SARS-CoV-2 and the long-term trajectories of psychological symptoms comparing long- and short-COVID groups.

Method: We analysed longitudinal data from the UCL COVID-19 Social Study (March 2020 to November 2021). We included data from adults living in England who reported contracting SARS-CoV-2 by November 2021 (n = 3115). Of these, 15.9% reported having had long COVID (n = 495). They were matched to participants who had short COVID using propensity score matching on a variety of demographic, socioeconomic and health covariates (n = 962 individuals with 13 325 observations) and data were further analysed using growth curve modelling.

Results: Depressive and anxiety symptoms increased immediately following the onset of infection in both long- and short-COVID groups. But the long-COVID group had substantially greater initial increases in depressive symptoms and heightened levels over 22 months follow-up. Initial increases in anxiety were not significantly different between groups, but only the short-COVID group experienced an improvement in anxiety over follow-up, leading to widening differences between groups.

Conclusions: The findings support work on the psychobiological pathways involved in the development of psychological symptoms relating to long COVID. The results highlight the need for monitoring of mental health and provision of adequate support to be interwoven with diagnosis and treatment of the physical consequences of long COVID.

Source: Fancourt D, Steptoe A, Bu F. Psychological consequences of long COVID: comparing trajectories of depressive and anxiety symptoms before and after contracting SARS-CoV-2 between matched long- and short-COVID groups. Br J Psychiatry. 2022 Dec 2:1-8. doi: 10.1192/bjp.2022.155. Epub ahead of print. PMID: 36458509. https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/psychological-consequences-of-long-covid-comparing-trajectories-of-depressive-and-anxiety-symptoms-before-and-after-contracting-sarscov2-between-matched-long-and-shortcovid-groups/923140B3F95F1158C0CDC188002531AE (Full text)

Post-COVID-19 syndrome/condition or long COVID: Persistent illness after acute SARS CoV-2 infection

Abstract:

Background: Approximately 10 million Australians have had confirmed SARS-CoV-2 infection. The waves of infection in the population have been succeeded by smaller waves of people affected by persistent illness following acute infection. Post-COVID-19 symptoms may extend for months following infection. There is a range of symptoms causing mild to debilitating impairment.

Objective: This article summarises what is currently understood about the pathophysiology, risk factors, symptoms and how to approach both the assessment and care of people with post-COVID-19 sequelae.

Discussion: Currently recommended is a person-centred approach from a multidisciplinary team, with general practitioners centrally coordinating care. As the understanding of post-acute COVID-19 is evolving, regularly updated or ‘living guidelines’ will be crucial for those affected to be provided with best care within the health system.

Source: Allard N, Miller A, Morgan M, Chakraborty S. Post-COVID-19 syndrome/condition or long COVID: Persistent illness after acute SARS CoV-2 infection. Aust J Gen Pract. 2022 Dec;51(12):952-957. doi: 10.31128/AJGP-05-22-6429. PMID: 36451331. https://www1.racgp.org.au/ajgp/2022/december/post-covid-19-syndrome-condition-or-long-covid (Full text)

Reduced Muscle Strength in Patients with Long-COVID-19 Syndrome Is Mediated by Limb Muscle Mass

Abstract:

Understanding the impact of COVID-19 on muscle strength may help to elucidate the organ systems that contribute to acute and chronic COVID-19 sequelae. We questioned whether patients with postdischarge symptoms after COVID-19 had compromised muscle strength compared with a control group, and if this potential relationship was mediated by the lower appendicular lean mass index (ALMI).

A total of 99 patients with long-COVID-19 and 97 control participants were screened. Maximal grip strength was assessed with a TKK 5101 digital dynamometer, and leg extension 1RM was measured using EGYM Smart Strength machines. Body composition (fat mass percentage, lean mass, visceral fat and appendicular lean mass index) was determined using a whole-body dual-energy X-ray densitometer.

Results showed that grip strength and leg extension strength were significantly higher in controls than in COVID-19 survivors (mean [SD], 32.82 [10.01] vs. 26.94 [10.33] kg; difference, 5.87 kg; P < 0.001) and (mean [SD], 93.98 [33.73] vs. 71.59 [33.70] kg; difference, 22.38 kg; P < 0.001), respectively). The relationship between long-COVID syndrome and grip/leg strength levels was partly mediated by ALMI, which explained 52% of the association for grip strength and 39% for leg extension.

Our findings provide novel insights into the mechanisms underlying the relationship between long-COVID syndrome and grip/leg strength levels, supporting the negative effects of long-COVID syndrome on muscle function.

Source: Ramírez-Vélez R, Legarra-Gorgoñon G, Oscoz-Ochandorena S, García-Alonso Y, García-Alonso N, Oteiza J, Ernaga Lorea A, Correa-Rodríguez M, Izquierdo M. Reduced Muscle Strength in Patients with Long-COVID-19 Syndrome Is Mediated by Limb Muscle Mass. J Appl Physiol (1985). 2022 Nov 30. doi: 10.1152/japplphysiol.00599.2022. Epub ahead of print. PMID: 36448687. https://journals.physiology.org/doi/abs/10.1152/japplphysiol.00599.2022 (Full text available as PDF file)

Effect of using a structured pacing protocol on post-exertional symptom exacerbation and health status in a longitudinal cohort with the post-COVID-19 syndrome

Abstract:

Background: Post Exertional Symptom Exacerbation (PESE) is a characteristic symptom of Post-COVID Syndrome (PCS).

Objectives: This prospective study investigated the effect of a 6-week structured World Health Organisation (WHO) Borg CR-10 5-phase pacing protocol on PESE episodes and quality of life in a cohort of individuals with long-standing PCS (average duration of symptoms was 17 months).

Methods: Participants received weekly telephone calls with a clinician to complete the Leeds PESE Questionnaire (LPQ) and identify the appropriate phase of the pacing protocol. EQ-5D 5L was completed at the intervention’s beginning and end to measure overall health.

Results: Thirty-one participants completed the 6-week protocol, with a statistically and clinically significant reduction in the average number of PESE episodes (from 3.4 episodes in week one to 1.1 in week six), with an average decrease of 16% (95% CI: 9% to 24%; p<0.001) each week, and reduction across all three exertional triggers (physical, cognitive, and emotional). Physical activity levels showed moderate improvements during the intervention period. Mean EQ-5D 5L scores improved from 51.4 points to 60.6 points (paired difference of 9.2 points, 95% CI: 3.2 to 15.2 points; p=0.004).

Conclusions: A structured pacing protocol significantly reduces PESE episodes and improves overall health in PCS.

Source: Parker M, Sawant HB, Flannery T, Tarrant R, Shardha J, Bannister R, Ross D, Halpin S, Greenwood DC, Sivan M. Effect of using a structured pacing protocol on post-exertional symptom exacerbation and health status in a longitudinal cohort with the post-COVID-19 syndrome. J Med Virol. 2022 Dec 2. doi: 10.1002/jmv.28373. Epub ahead of print. PMID: 36461167. https://pubmed.ncbi.nlm.nih.gov/36461167/

Impact of pre-existing chronic viral infection and reactivation on the development of long COVID

Abstract:

Background: The presence and reactivation of chronic viral infections such as Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human immunodeficiency virus (HIV) have been proposed as potential contributors to Long COVID (LC), but studies in well-characterized post-acute cohorts of individuals with COVID-19 over a longer time course consistent with current case definitions of LC are limited.

Methods: In a cohort of 280 adults with prior SARS-CoV-2 infection, we assessed the presence and types of LC symptoms and prior medical history (including COVID-19 history and HIV status), and performed serological testing for EBV and CMV using a commercial laboratory. We used covariate-adjusted binary logistic regression models to identify independent associations between variables and LC symptoms.

Results: We observed that LC symptoms such as fatigue and neurocognitive dysfunction at a median of 4months following initial diagnosis were independently associated with serological evidence suggesting recent EBV reactivation (early antigen-D [EA-D] IgG positivity) or high nuclear antigen (EBNA) IgG levels, but not with ongoing EBV viremia. Serological evidence suggesting recent EBV reactivation (EA-D IgG) was most strongly associated with fatigue (OR 2.12). Underlying HIV infection was also independently associated with neurocognitive LC (OR 2.5). Interestingly, participants who had serologic evidence of prior CMV infection were less likely to develop neurocognitive LC (OR 0.52).

Conclusion: Overall, these findings suggest differential effects of chronic viral co-infections on the likelihood of developing LC and predicted distinct syndromic patterns. Further assessment during the acute phase of COVID-19 is warranted.

Trial registration: Long-term Impact of Infection with Novel Coronavirus (LIINC); NCT04362150FUNDING. This work was supported by the National Institute of Allergy and Infectious Diseases NIH/NIAID 3R01AI141003-03S1 to TJ Henrich, R01AI158013 to M Gandhi and M Spinelli, K24AI145806 to P Hunt, and by the Zuckerberg San Francisco Hospital Department of Medicine and Division of HIV, Infectious Diseases, and Global Medicine. MJP is supported on K23 A137522 and received support from the UCSFBay Area Center for AIDS Research (P30-AI027763).

Source: Peluso MJ, Deveau TM, Munter SE, Ryder DM, Buck AM, Beck-Engeser G, Chan F, Lu S, Goldberg SA, Hoh R, Tai V, Torres L, Iyer NS, Deswal M, Ngo LH, Buitrago M, Rodriguez AE, Chen JY, Yee BC, Chenna A, Winslow JW, Petropoulos CJ, Deitchman AN, Hellmuth J, Spinelli MA, Durstenfeld MS, Hsue PY, Kelly JD, Martin JN, Deeks SG, Hunt PW, Henrich TJ. Impact of pre-existing chronic viral infection and reactivation on the development of long COVID. J Clin Invest. 2022 Dec 1:e163669. doi: 10.1172/JCI163669. Epub ahead of print. PMID: 36454631. https://www.jci.org/articles/view/163669 (Full text)

Incidence of long COVID-19 in people with previous SARS-Cov2 infection: a systematic review and meta-analysis of 120,970 patients

Abstract:

The long-term consequences of the coronavirus disease 19 (COVID-19) are likely to be frequent but results hitherto are inconclusive. Therefore, we aimed to define the incidence of long-term COVID signs and symptoms as defined by the World Health Organization, using a systematic review and meta-analysis of observational studies.

A systematic search in several databases was carried out up to 12 January 2022 for observational studies reporting the cumulative incidence of long COVID signs and symptoms divided according to body systems affected. Data are reported as incidence and 95% confidence intervals (CIs). Several sensitivity and meta-regression analyses were performed. Among 11,162 papers initially screened, 196 were included, consisting of 120,970 participants (mean age: 52.3 years; 48.8% females) who were followed-up for a median of six months.

The incidence of any long COVID symptomatology was 56.9% (95% CI 52.2-61.6). General long COVID signs and symptoms were the most frequent (incidence of 31%) and digestive issues the least frequent (7.7%). The presence of any neurological, general and cardiovascular long COVID symptomatology was most frequent in females. Higher mean age was associated with higher incidence of psychiatric, respiratory, general, digestive and skin conditions. The incidence of long COVID symptomatology was different according to continent and follow-up length. Long COVID is a common condition in patients who have been infected with SARS-CoV-2, regardless of the severity of the acute illness, indicating the need for more cohort studies on this topic.

Source: Di Gennaro F, Belati A, Tulone O, Diella L, Fiore Bavaro D, Bonica R, Genna V, Smith L, Trott M, Bruyere O, Mirarchi L, Cusumano C, Dominguez LJ, Saracino A, Veronese N, Barbagallo M. Incidence of long COVID-19 in people with previous SARS-Cov2 infection: a systematic review and meta-analysis of 120,970 patients. Intern Emerg Med. 2022 Nov 30:1–9. doi: 10.1007/s11739-022-03164-w. Epub ahead of print. PMID: 36449260; PMCID: PMC9709360. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9709360/ (Full text)

A multi-omics based anti-inflammatory immune signature characterizes Long COVID Syndrome

Abstract:

To investigate Long COVID Syndrome (LCS) pathophysiology, we performed an exploratory study with blood plasma derived from three groups: 1) healthy vaccinated individuals without SARS-CoV-2 exposure; 2) asymptomatic recovered patients at least three months after SARS-CoV-2 infection and; 3) symptomatic patients at least 3 months after SARS-CoV-2 infection with chronic fatigue syndrome or similar symptoms, here designated as Long COVID Syndrome (LCS) patients.

Multiplex cytokine profiling indicated slightly elevated pro-inflammatory cytokine levels in recovered individuals in contrast to LCS patients. Plasma proteomics demonstrated low levels of acute phase proteins and macrophage-derived secreted proteins in LCS. High levels of anti-inflammatory oxylipins including omega-3 fatty acids in LCS were detected by eicosadomics, whereas targeted metabolic profiling indicated high levels of anti-inflammatory osmolytes taurine and hypaphorine, but low amino acid and triglyceride levels and deregulated acylcarnithines. A model considering alternatively polarized macrophages as a major contributor for these molecular alterations is presented.

Source: Kovarik JJ, Bileck A, Hagn G, Meier-Menches SM, Frey T, Kaempf A, Hollenstein M, Shoumariyeh T, Skos L, Reiter B, Gerner MC, Spannbauer A, Hasimbegovic E, Schmidl D, Garhöfer G, Gyöngyösi M, Schmetterer KG, Gerner C. A multi-omics based anti-inflammatory immune signature characterizes Long COVID Syndrome. iScience. 2022 Dec 5:105717. doi: 10.1016/j.isci.2022.105717. Epub ahead of print. PMID: 36507225; PMCID: PMC9719844. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9719844/ (Full text)

Connectivity between Salience and Default Mode Networks and subcortical nodes distinguishes between two classes of ME/CFS

Abstract:

Myalgic Encephalomyelitis or Chronic Fatigue Syndrome (ME/CFS) is a debilitating disease with unknown pathophysiology. Functional MRI (fMRI) studies in ME/CFS have reported disparate connectivities for the brain salience (SA) and default mode (DMN) networks.

In this study, we acquired resting state and task fMRI with an advanced scanner for improved subject numbers: 24 healthy controls (HC) and 42 ME/CFS patients, 18 meeting International Consensus Criteria (ICC) and 24 meeting Fukuda criteria. We evaluated mean FC between SA and DMN network hub, and subcortical regions known to be involved in ME/CFS. We tested the hypothesis that ME/CFS connectivity differed from HC and the ICC and Fukuda classes are distinguished by different connectivities with HC for different pairs of SA, DMN or subcortical hubs.

During resting state fMRI only two connections differed from HC, both for Fukuda ME/CFS and both with an SA hub. During task fMRI 10 ME/CFS connections differed from HC, 5 for ICC and 5 for Fukuda. None were common to both classes. Eight of the 10 different connections involved an SA hub, six of 10 were weaker in ME/CFS, 4 stronger.

SA connections to the hippocampus and brainstem reticular activation system (RAS) differed from and were stronger than HC. The SA mediates the relative activity of the DMN and executive networks and imbalance will have functional consequences. The RAS and hippocampus modulate cortical activation. Different regulatory connections are consistent with the impaired cognitive performance and sleep-wake cycle of ME/CFS. Different neuropathology is involved in ICC and Fukuda classes.

Source: Su J, Thapaliya K, Eaton-Fitch N, Marshall-Gradisnik SM, Barnden LR. Connectivity between Salience and Default Mode Networks and subcortical nodes distinguishes between two classes of ME/CFS. Brain Connect. 2022 Nov 9. doi: 10.1089/brain.2022.0049. Epub ahead of print. PMID: 36352819. https://pubmed.ncbi.nlm.nih.gov/36352819/

Long COVID: mechanisms, risk factors and recovery

Abstract:

New findings: What is the topic of this review? The emerging condition of long COVID, its epidemiology, pathophysiological impacts on patients of different backgrounds, physiological mechanisms emerging as explanations of the condition, and treatment strategies being trialled. The review leads from a Physiological Society online conference on this topic. What advances does it highlight? Progress in understanding the pathophysiology and cellular mechanisms underlying Long COVID and potential therapeutic and management strategies.

Abstract: Long COVID, the prolonged illness and fatigue suffered by a small proportion of those infected with SARS-CoV-2, is placing an increasing burden on individuals and society. A Physiological Society virtual meeting in February 2022 brought clinicians and researchers together to discuss the current understanding of long COVID mechanisms, risk factors and recovery.

This review highlights the themes arising from that meeting. It considers the nature of long COVID, exploring its links with other post-viral illnesses such as myalgic encephalomyelitis/chronic fatigue syndrome, and highlights how long COVID research can help us better support those suffering from all post-viral syndromes. Long COVID research started particularly swiftly in populations routinely monitoring their physical performance – namely the military and elite athletes.

The review highlights how the high degree of diagnosis, intervention and monitoring of success in these active populations can suggest management strategies for the wider population. We then consider how a key component of performance monitoring in active populations, cardiopulmonary exercise training, has revealed long COVID-related changes in physiology – including alterations in peripheral muscle function, ventilatory inefficiency and autonomic dysfunction. The nature and impact of dysautonomia are further discussed in relation to postural orthostatic tachycardia syndrome, fatigue and treatment strategies that aim to combat sympathetic overactivation by stimulating the vagus nerve.

We then interrogate the mechanisms that underlie long COVID symptoms, with a focus on impaired oxygen delivery due to micro-clotting and disruption of cellular energy metabolism, before considering treatment strategies that indirectly or directly tackle these mechanisms. These include remote inspiratory muscle training and integrated care pathways that combine rehabilitation and drug interventions with research into long COVID healthcare access across different populations.

Overall, this review showcases how physiological research reveals the changes that occur in long COVID and how different therapeutic strategies are being developed and tested to combat this condition.

Source: Astin R, Banerjee A, Baker MR, Dani M, Ford E, Hull JH, Lim PB, McNarry M, Morten K, O’Sullivan O, Pretorius E, Raman B, Soteropoulos DS, Taquet M, Hall CN. Long COVID: mechanisms, risk factors and recovery. Exp Physiol. 2022 Nov 22. doi: 10.1113/EP090802. Epub ahead of print. PMID: 36412084. https://physoc.onlinelibrary.wiley.com/doi/10.1113/EP090802 (Full text)