Tag: long covid review

Cellular and molecular biomarkers of long COVID: a scoping review

Abstract:

Background: Long-COVID (LC) encompasses diverse symptoms lasting months after the initial SARS-CoV-2 infection. Symptoms can be debilitating and affect the quality of life of individuals with LC and their families. Although the symptoms of LC are well described, the aetiology of LC remains unclear, and consequently, patients may be underdiagnosed. Identification of LC specific biomarkers is therefore paramount for the diagnosis and clinical management of the syndrome. This scoping review describes the molecular and cellular biomarkers that have been identified to date with potential use for diagnosis or prediction of LC.

Methods: This review was conducted using the Joanna Briggs Institute (JBI) Methodology for Scoping Reviews. A search was executed in the MEDLINE and EMBASE databases, as well as in the grey literature for original studies, published until October 5th, 2022, reporting biomarkers identified in participants with LC symptoms (from all ages, ethnicities, and sex), with a previous infection of SARS-CoV-2. Non-English studies, cross-sectional studies, studies without a control group, and pre-prints were excluded. Two reviewers independently evaluated the studies, extracted population data and associated biomarkers.

Findings: 23 cohort studies were identified, involving 2163 LC patients [median age 51.8 years, predominantly female sex (61.10%), white (75%), and non-vaccinated (99%)]. A total of 239 candidate biomarkers were identified, consisting mainly of immune cells, immunoglobulins, cytokines, and other plasma proteins. 19 of the 239 candidate biomarkers identified were evaluated by the authors, by means of receiver operating characteristic (ROC) curves.

Interpretation: Diverse cellular and molecular biomarkers for LC have been proposed. Validation of candidate biomarkers in independent samples should be prioritized. Modest reported performance (particularly in larger studies) suggests LC may encompass many distinct aetiologies, which should be explored e.g., by stratifying by symptom clusters and/or sex.

Source: Espín E, Yang C, Shannon CP, Assadian S, He D, Tebbutt SJ. Cellular and molecular biomarkers of long COVID: a scoping review. EBioMedicine. 2023 Apr 8;91:104552. doi: 10.1016/j.ebiom.2023.104552. Epub ahead of print. PMID: 37037165; PMCID: PMC10082390. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10082390/ (Full text)

Exercise Pathophysiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-Acute Sequelae of SARS-CoV-2: More in Common Than Not?

Abstract:

Topic importance: Post-Acute Sequelae of SARS-CoV-2 (PASC) is a long-term consequence of acute infection from coronavirus disease 2019 (COVID-19). Clinical overlap between PASC and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) has been observed, with shared symptoms including intractable fatigue, postexertional malaise, and orthostatic intolerance. The mechanistic underpinnings of such symptoms are poorly understood.

Review findings: Early studies suggest deconditioning as the primary explanation for exertional intolerance in PASC. Cardiopulmonary exercise testing (CPET) reveals perturbations related to systemic blood flow and ventilatory control associated with acute exercise intolerance in PASC, which are not typical of simple detraining. Hemodynamic and gas exchange derangements in PASC have substantial overlap with those observed with ME/CFS, suggestive of shared mechanisms.

Summary: This review aims to illustrate exercise pathophysiologic commonalities between PASC and ME/CFS that will help guide future diagnostics and treatment.

Source: Joseph P, Singh I, Oliveira R, Capone CA, Mullen MP, Cook DB, Stovall MC, Squires J, Madsen K, Waxman AB, Systrom DM. Exercise Pathophysiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-Acute Sequelae of SARS-CoV-2: More in Common Than Not? Chest. 2023 Apr 11:S0012-3692(23)00502-0. doi: 10.1016/j.chest.2023.03.049. Epub ahead of print. PMID: 37054777; PMCID: PMC10088277. https://pubmed.ncbi.nlm.nih.gov/37054777/

Immunological dysfunction and mast cell activation syndrome in long COVID

Abstract:

At least 65 million people around the world suffer from long COVID, with the majority of cases occurring in the productive age (36–50 years old). Individuals with long COVID are confounded with multiple organ system dysfunctions, long-term organ injury sequelae, and a decreased quality of life. There is an overlapping of risk factors between long COVID and other postviral infection syndromes, so advances in research could also benefit other groups of patients.

Long COVID is the consequence of multiple immune system dysregulation, such as T-cell depletion, innate immune cell hyperactivity, lack of naive T and B cells, and elevated signature of pro-inflammatory cytokines, together with persistent SARS-CoV2 reservoir and other consequences of acute infection.

There is an activated condition of mast cells in long COVID, with abnormal granulation and excessive inflammatory cytokine release. A study by Weinstock et al. indicates that patients with long COVID suffer the same clinical syndrome as patients with mast cell activation syndrome (MCAS).

Diagnosis and treatment of MCAS in patients with long COVID will provide further symptomatic relief, and manage mast cell-mediated hyperinflammation states, which could be useful in the long-term control and recovery of such patients.

Source: Sumantri, Stevent; Rengganis, Iris. Immunological dysfunction and mast cell activation syndrome in long COVID. Asia Pacific Allergy ():10.5415/apallergy.0000000000000022, March 30, 2023. | DOI: 10.5415/apallergy.0000000000000022 https://journals.lww.com/apallergy/Fulltext/9900/Immunological_dysfunction_and_mast_cell_activation.2.aspx (Full text)

Long COVID in autoimmune rheumatic diseases

Abstract:

Consequences of Corona Virus Disease-19 (COVID-19) in patients with rheumatic diseases (RDs) are clinically diverse. SARS-CoV-2 infection has been associated with various autoimmune and rheumatic manifestations over the past three years. Emerging evidence points to the possibility of Long COVID predisposition in rheumatic patients due to the changes in immune regulatory response. The aim of this article was to overview data on the pathobiology of Long COVID in patients with RDs.

Related risk factors, clinical characteristics, and prognosis of Long COVID in RDs were analyzed. Relevant articles were retrieved from Medline/PubMed, Scopus, and Directory of Open Access Journals (DOAJ). Diverse mechanisms of viral persistence, chronic low-grade inflammation, lasting production of autoantibodies, endotheliopathy, vascular complications, and permanent tissue damage have been described in association with Long COVID. Patients with RDs who survive COVID-19 often experience severe complications due to the immune disbalance resulting in multiple organ damage. Regular monitoring and treatment are warranted in view of the accumulating evidence.

Source: Fedorchenko Y, Zimba O. Long COVID in autoimmune rheumatic diseases. Rheumatol Int. 2023 Mar 30:1–11. doi: 10.1007/s00296-023-05319-0. Epub ahead of print. PMID: 36995436; PMCID: PMC10061411. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10061411/ (Full text)

Metabolic and endocrine complications of long COVID-19: A review

Abstract:

Over the past two years, the COVID-19 outbreak caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), centralized the interest of the health care systems and the scientific world. Majority of the COVID-19 infected individuals fully recover. However, about 12%-50% of patients experience a variety of mid- and long-term effects after recovering from the initial illness. These mid- and long-term effects are collectively known as post-COVID-19 condition or ‘long-COVID’. In the coming months, the long-term consequences of COVID-19 on the metabolic and endocrine systems may expect to rise and pose a global health care challenge. This review article aims to discuss the possible metabolic and endocrine complications of long-COVID and the relevant research findings.

Source: Bandara T, Deshmukh HA, Abdalla M, Sathyapalan T. Metabolic and endocrine complications of long COVID-19: A review. Exp Clin Endocrinol Diabetes. 2023 Mar 28. doi: 10.1055/a-2063-8697. Epub ahead of print. PMID: 36977491. https://pubmed.ncbi.nlm.nih.gov/36977491/

COVID-19 Vaccination for the Prevention and Treatment of Long COVID: A Systematic Review and Meta-analysis

Abstract:

Empirical evidence addressing the association between SARS-CoV-2 vaccination and long COVID would guide public health priorities and inform personal health decisions. Herein, the co-primary objectives are to determine the differential risk of long COVID in vaccinated versus unvaccinated patients, and the trajectory of long COVID following vaccination.

Of 2775 articles identified via systematic search, 17 were included, and 6 were meta-analyzed. Meta-analytic results determined that at least one vaccine dose was associated with a protective effect against long COVID (OR 0.539, 95% CI 0.295-0.987, p = 0.045, N= 257 817).

Qualitative analysis revealed that trajectories of pre-existing long COVID following vaccination were mixed, with most patients reporting no changes. The evidence herein supports SARS-CoV-2 vaccination for the prevention of long COVID, and recommends long COVID patients adhere to standard SARS-CoV-2 vaccination schedules.

Source: Ceban F, Kulzhabayeva D, Rodrigues NB, Di Vincenzo JD, Gill H, Subramaniapillai M, Lui LMW, Cao B, Mansur RB, Ho RC, Burke MJ, Rhee TG, Rosenblat JD, McIntyre RS. COVID-19 Vaccination for the Prevention and Treatment of Long COVID: A Systematic Review and Meta-analysis. Brain Behav Immun. 2023 Mar 27:S0889-1591(23)00079-X. doi: 10.1016/j.bbi.2023.03.022. Epub ahead of print. PMID: 36990297; PMCID: PMC10067136. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10067136/ (Full text)

What is the role of brown adipose tissue in metabolic health: lessons learned and future perspectives in the long COVID?

Abstract:

Metabolic physiology plays a key role in maintaining our health and resilience. Metabolic disorders can lead to serious illnesses, including obesity. The pathogenesis of the new long COVID syndrome in individuals with long-term recovery after SARS-Co-2 infection is still incomplete. Thus there is growing attention in the study of adipose tissue activities, especially brown adipose tissue (BAT) and associated resilience which plays a crucial role in different types of obesity as potential targets for pharmacologic and nutritional interventions in the context of obesity and long COVID.

The number of studies examining mechanisms underlying BAT has grown rapidly in the last 10 years despite of role of BAT in individuals with COVID-19 and long COVID is modest. Therefore, this review aims to sum up data examining BAT activities, its resilience in health, obesity, and the possible link to long COVID.

The search was conducted on studies published in English mostly between 2004 and 2022 in adult humans and animal models. Database searches were conducted using PubMed, Scopus, and Google Scholar for key terms including adipose tissue, BAT, adipokinins, obesity, VPF/VEGF, and pathogenesis. From the initial search through the database were identified relevant articles that met inclusion and exclusion criteria and our data regarding adipose tissues were presented in this review.

It will discuss adiposity tissue activities. Current literature suggests that there are BAT integral effects to whitening and browning fat phenomenons which reflect the homeostatic metabolic adaptive ability for environmental demand or survival/adaptive mechanisms. We also review neural and vascular impacts in BAT that play a role in resilience and obesity. Finally, we discuss the role of BAT in the context of long COVID in basic research and clinical research.

Source: Muzyka, I., Revenko, O., Kovalchuk, I. et al. What is the role of brown adipose tissue in metabolic health: lessons learned and future perspectives in the long COVID?. Inflammopharmacol (2023). https://doi.org/10.1007/s10787-023-01195-z (Full text)

Post-COVID Syndrome

Abstract:

Background: As defined by the WHO, the term post-COVID syndrome (PCS) embraces a group of symptoms that can occur following the acute phase of a SARS-CoV-2 infection and as a consequence thereof. PCS is found mainly in adults, less frequently in children and adolescents. It can develop both in patients who initially had only mild symptoms or none at all and in those who had a severe course of coronavirus disease 2019 (COVID-19).

Methods: The data presented here were derived from a systematic literature review.

Results: PCS occurs in up to 15% of unvaccinated adults infected with SARS-CoV-2. The prevalence has decreased in the most recent phase of the pandemic and is lower after vaccination. The pathogenesis of PCS has not yet been fully elucidated. Virus triggered inflammation, autoimmunity, endothelial damage (to blood vessels), and persistence of virus are thought to be causative. Owing to the broad viral tropism, different organs are involved and the symptoms vary. To date, there are hardly any evidence-based recommendations for definitive diagnosis of PCS or its treatment.

Conclusion: The gaps in our knowledge mean that better documentation of the prevalence of PCS is necessary to compile the data on which early detection, diagnosis, and treatment can be based. To ensure the best possible care of patients with PCS, regional PCS centers and networks embracing existing structures from all healthcare system sectors and providers should be set up and structured diagnosis and treatment algorithms should be established. Given the sometimes serious consequences of PCS for those affected, it seems advisable to keep the number of SARS-CoV-2 infections low by protective measures tailored to the prevailing pandemic situation.

Source: Hallek M, Adorjan K, Behrends U, Ertl G, Suttorp N, Lehmann C. Post-COVID Syndrome. Dtsch Arztebl Int. 2023 Jan 27;120(4):48-55. doi: 10.3238/arztebl.m2022.0409. PMID: 36633452; PMCID: PMC10060997. https://www.aerzteblatt.de/int/archive/article/229208 (Full text)

Risk Factors Associated With Post−COVID-19 Condition A Systematic Review and Meta-analysis

Abstract:

Importance  Post−COVID-19 condition (PCC) is a complex heterogeneous disorder that has affected the lives of millions of people globally. Identification of potential risk factors to better understand who is at risk of developing PCC is important because it would allow for early and appropriate clinical support.

Objective  To evaluate the demographic characteristics and comorbidities that have been found to be associated with an increased risk of developing PCC.

Data sources  Medline and Embase databases were systematically searched from inception to December 5, 2022.

Study Selection  The meta-analysis included all published studies that investigated the risk factors and/or predictors of PCC in adult (≥18 years) patients.

Data Extraction and Synthesis  Odds ratios (ORs) for each risk factor were pooled from the selected studies. For each potential risk factor, the random-effects model was used to compare the risk of developing PCC between individuals with and without the risk factor. Data analyses were performed from December 5, 2022, to February 10, 2023.

Main Outcomes and Measures  The risk factors for PCC included patient age; sex; body mass index, calculated as weight in kilograms divided by height in meters squared; smoking status; comorbidities, including anxiety and/or depression, asthma, chronic kidney disease, chronic obstructive pulmonary disease, diabetes, immunosuppression, and ischemic heart disease; previous hospitalization or ICU (intensive care unit) admission with COVID-19; and previous vaccination against COVID-19.

Results  The initial search yielded 5334 records of which 255 articles underwent full-text evaluation, which identified 41 articles and a total of 860 783 patients that were included. The findings of the meta-analysis showed that female sex (OR, 1.56; 95% CI, 1.41-1.73), age (OR, 1.21; 95% CI, 1.11-1.33), high BMI (OR, 1.15; 95% CI, 1.08-1.23), and smoking (OR, 1.10; 95% CI, 1.07-1.13) were associated with an increased risk of developing PCC. In addition, the presence of comorbidities and previous hospitalization or ICU admission were found to be associated with high risk of PCC (OR, 2.48; 95% CI, 1.97-3.13 and OR, 2.37; 95% CI, 2.18-2.56, respectively). Patients who had been vaccinated against COVID-19 with 2 doses had a significantly lower risk of developing PCC compared with patients who were not vaccinated (OR, 0.57; 95% CI, 0.43-0.76).

Conclusions and Relevance  This systematic review and meta-analysis demonstrated that certain demographic characteristics (eg, age and sex), comorbidities, and severe COVID-19 were associated with an increased risk of PCC, whereas vaccination had a protective role against developing PCC sequelae. These findings may enable a better understanding of who may develop PCC and provide additional evidence for the benefits of vaccination.

Trial Registration  PROSPERO Identifier: CRD42022381002

Source: Tsampasian V, Elghazaly H, Chattopadhyay R, et al. Risk Factors Associated With Post−COVID-19 Condition: A Systematic Review and Meta-analysis. JAMA Intern Med. Published online March 23, 2023. doi:10.1001/jamainternmed.2023.0750 https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2802877 (Full text)

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

Abstract:

COVID-19, with persistent and new onset of symptoms such as fatigue, post-exertional malaise, and cognitive dysfunction that last for months and impact everyday functioning, is referred to as Long COVID under the general category of post-acute sequelae of SARS-CoV-2 infection (PASC). PASC is highly heterogenous and may be associated with multisystem tissue damage/dysfunction including acute encephalitis, cardiopulmonary syndromes, fibrosis, hepatobiliary damages, gastrointestinal dysregulation, myocardial infarction, neuromuscular syndromes, neuropsychiatric disorders, pulmonary damage, renal failure, stroke, and vascular endothelial dysregulation. A better understanding of the pathophysiologic mechanisms underlying PASC is essential to guide prevention and treatment.

This review addresses potential mechanisms and hypotheses that connect SARS-CoV-2 infection to long-term health consequences. Comparisons between PASC and other virus-initiated chronic syndromes such as myalgic encephalomyelitis/chronic fatigue syndrome and postural orthostatic tachycardia syndrome will be addressed. Aligning symptoms with other chronic syndromes and identifying potentially regulated common underlining pathways may be necessary for understanding the true nature of PASC.

The discussed contributors to PASC symptoms include sequelae from acute SARS-CoV-2 injury to one or more organs, persistent reservoirs of the replicating virus or its remnants in several tissues, re-activation of latent pathogens such as Epstein-Barr and herpes viruses in COVID-19 immune-dysregulated tissue environment, SARS-CoV-2 interactions with host microbiome/virome communities, clotting/coagulation dysregulation, dysfunctional brainstem/vagus nerve signaling, dysautonomia or autonomic dysfunction, ongoing activity of primed immune cells, and autoimmunity due to molecular mimicry between pathogen and host proteins. The individualized nature of PASC symptoms suggests that different therapeutic approaches may be required to best manage specific patients.

Source: Sherif ZA, Gomez CR, Connors TJ, Henrich TJ, Reeves WB; RECOVER Mechanistic Pathway Task Force. Pathogenic mechanisms of post-acute sequelae of SARS-CoV-2 infection (PASC). Elife. 2023 Mar 22;12:e86002. doi: 10.7554/eLife.86002. PMID: 36947108; PMCID: PMC10032659. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10032659/ (Full text)