Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-COVID Syndrome: A Common Neuroimmune Ground?

Abstract:

A Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating chronic disease of unknown aetiology under growing interest now in view of the increasingly recognized post-COVID syndrome as a new entity with similar clinical presentation.

We performed the first cross-sectional study of ME/CFS in community population in Russia and then described and compared some clinical and pathophysiological characteristics of ME/CFS and post-COVID syndrome as neuroimmune disorders.

Of the cohort of 76 individuals who suggested themselves suffering from ME/CFS 56 subsequently were confirmed as having CFS/ME according to ≥1 of the 4 most commonly used case definition.

Of the cohort of 14 individuals with post-COVID-19 syndrome 14 met diagnostic criteria for ME/CFS. The prevalence of clinically expressed and subclinical anxiety and depression in ME / CFS and post-COVID ME/CFS did not differ significantly from that in healthy individuals.

Severity of anxiety / depressive symptoms did not correlate with the severity of fatigue neigther in ME / CFS nor in post-COVID ME/CFS, but the positive correlation was found between the severity of fatigue and 20 other symptoms of ME / CFS related to the domains of “post-exertional exhaustion”, “immune dysfunction”, “sleep disturbances”, “dysfunction of the autonomic nervous system”, “neurological sensory / motor disorders” and “pain syndromes”.

Immunological abnormalities were identified in 12/12 patients with ME / CFS according to the results of laboratory testing.

The prevalence of postural orthostatic tachycardia assessed by the active standing test was 37.5% in ME / CFS and 75.0% in post-COVID ME/CFS (the latter was higher than in healthy controls, p = 0.02).  There was a more pronounced increase in heart rate starting from the 6th minute of the test in post-COVID ME/CFS compared with the control group.

Assessment of the functional characteristics of microcirculation by laser doppler flowmetry revealed obvious and very similar changes in ME/CFS and post-COVID ME/CFS compared to the healthy controls.  The identified pattern corresponded to the hyperemic form of microcirculation disorders, usually observed in acute inflammatory processes or in deficiency of systemic vasoconstriction influences.

Source: Ryabkova, V.A.; Gavrilova, N.Y.; Fedotkina, T.V.; Churilov, L.P.; Shoenfeld, Y. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post-COVID Syndrome: A Common Neuroimmune Ground?. Preprints 2022, 2022090289 (doi: 10.20944/preprints202209.0289.v1) https://www.preprints.org/manuscript/202209.0289/v1 (Full study available as PDF file)

Dysregulated autoantibodies targeting vaso- and immunoregulatory receptors in Post COVID Syndrome correlate with symptom severity

Most patients with Post COVID Syndrome (PCS) present with a plethora of symptoms without clear evidence of organ dysfunction. A subset of them fulfills diagnostic criteria of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Symptom severity of ME/CFS correlates with natural regulatory autoantibody (AAB) levels targeting several G-protein coupled receptors (GPCR).

In this exploratory study, we analyzed serum AAB levels against vaso- and immunoregulatory receptors, mostly GPCRs, in 80 PCS patients following mild-to-moderate COVID-19, with 40 of them fulfilling diagnostic criteria of ME/CFS. Healthy seronegative (n=38) and asymptomatic post COVID-19 controls (n=40) were also included in the study as control groups.

We found lower levels for various AABs in PCS compared to at least one control group, accompanied by alterations in the correlations among AABs. Classification using random forest indicated AABs targeting ADRB2, STAB1, and ADRA2A as the strongest classifiers (AABs stratifying patients according to disease outcomes) of post COVID-19 outcomes. Several AABs correlated with symptom severity in PCS groups. Remarkably, severity of fatigue and vasomotor symptoms were associated with ADRB2 AAB levels in PCS/ME/CFS patients.

Our study identified dysregulation of AAB against various receptors involved in the autonomous nervous system (ANS), vaso-, and immunoregulation and their correlation with symptom severity, pointing to their role in the pathogenesis of PCS.

Source: Franziska Sotzny, Igor Salerno Filgueiras, Claudia Kedor, Helma Freitag, Kirsten Wittke, Sandra Bauer, Nuno Sepúlveda, Dennyson Leandro Mathias da Fonseca, Gabriela Crispim Baiocchi, Alexandre H. C. Marques, Myungjin Kim, Tanja Lange, Desirée Rodrigues Plaça, Finn Luebber, Frieder M. Paulus, Roberta De Vito, Igor Jurisica, Kai Schulze-Forster, Friedemann Paul, Judith Bellmann-Strobl, Rebekka Rust, Uta Hoppmann, Yehuda Shoenfeld, Gabriela Riemekasten, Harald Heidecke, Otavio Cabral-Marques, Carmen Scheibenbogen. Dysregulated autoantibodies targeting vaso- and immunoregulatory receptors in Post COVID Syndrome correlate with symptom severity. Front. Immunol., 27 September 2022
Sec. Autoimmune and Autoinflammatory Disorders https://doi.org/10.3389/fimmu.2022.981532 (Full text)

Bioinformatics and systems biology approach to identify the pathogenetic link of Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Background: The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global crisis. Although many people recover from COVID-19 infection, they are likely to develop persistent symptoms similar to those of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) after discharge. Those constellations of symptoms persist for months after infection, called Long COVID, which may lead to considerable financial burden and healthcare challenges. However, the mechanisms underlying Long COVID and ME/CFS remain unclear.

Methods: We collected the genes associated with Long COVID and ME/CFS in databases by restricted screening conditions and clinical sample datasets with limited filters. The common genes for Long COVID and ME/CFS were finally obtained by taking the intersection. We performed several advanced bioinformatics analyses based on common genes, including gene ontology and pathway enrichment analyses, protein–protein interaction (PPI) analysis, transcription factor (TF)–gene interaction network analysis, transcription factor–miRNA co-regulatory network analysis, and candidate drug analysis prediction.

Results: We found nine common genes between Long COVID and ME/CFS and gained a piece of detailed information on their biological functions and signaling pathways through enrichment analysis. Five hub proteins (IL-6, IL-1B, CD8A, TP53, and CXCL8) were collected by the PPI network. The TF–gene and TF–miRNA coregulatory networks were demonstrated by NetworkAnalyst. In the end, 10 potential chemical compounds were predicted.

Conclusion: This study revealed common gene interaction networks of Long COVID and ME/CFS and predicted potential therapeutic drugs for clinical practice. Our findings help to identify the potential biological mechanism between Long COVID and ME/CFS. However, more laboratory and multicenter evidence is required to explore greater mechanistic insight before clinical application in the future.

Source: Lv Y, Zhang T, Cai J, Huang C, Zhan S and Liu J. Bioinformatics and systems biology approach to identify the pathogenetic link of Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Front. Immunol. 13:952987  https://www.frontiersin.org/articles/10.3389/fimmu.2022.952987/full (Full text)

Long-term neuromuscular consequences of SARS-Cov-2 and their similarities with myalgic encephalomyelitis/chronic fatigue syndrome: results of the retrospective CoLGEM study

Abstract:

Background: Patients with long-COVID often complain of continuous fatigue, myalgia, sleep problems, cognitive dysfunction, and post-exertional malaise. No data are available on EMG recording of evoked myopotentials (M-waves) or exercise-induced alterations in long-COVID patients, providing evidence of muscle membrane fatigue. Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) develops in more than half of patients after an infectious disease, particularly viral diseases. A large proportion (around 70%) of these patients have neuromuscular disorders with M-wave alterations during and after exercise. Our hypothesis was that M-wave alterations would be also found in long-COVID patients, in association with neuromuscular symptoms, similar to ME/CFS.

Methods: This retrospective observational ColGEM (Covid LonG Encéphalomyelite Myalgique) study compared 59 patients with long-COVID and 55 ME/CFS patients with a history of severe infection who presented before the COVID pandemic. All of these patients underwent the same protocol consisting of a questionnaire focusing on neural and neuromuscular disorders and M-wave recording in the rectus femoris muscle before, during, and 10 min after a progressive cycling exercise. Maximal handgrip strength (MHGS) and maximal exercise power were also measured. The frequency of symptoms and magnitude of M-wave changes in the two groups were compared using non-parametric and parametric tests.

Results: The frequency of fatigue, myalgia, sleep problems, cognitive dysfunction, and post-exertional malaise as well as the magnitude of exercise-induced M-wave alterations were the same in the two groups. By contrast, digestive problems were less present in long-COVID. M-wave alterations were greater in ME/CFS patients as in those with long-COVID when the highest muscle strength and highest exercise performance were measured.

Conclusions: These high clinical and biological similarities between long-COVID and ME/CFS support the hypothesis that SARS-Cov-2 infection can cause ME/CFS symptoms. Trial registration Registered retrospectively.

Source: Retornaz F, Rebaudet S, Stavris C, Jammes Y. Long-term neuromuscular consequences of SARS-Cov-2 and their similarities with myalgic encephalomyelitis/chronic fatigue syndrome: results of the retrospective CoLGEM study. J Transl Med. 2022 Sep 24;20(1):429. doi: 10.1186/s12967-022-03638-7. PMID: 36153556. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-022-03638-7 (Full text)

A preliminary estimate of the economic impact of long COVID in the United States

Post-Acute Sequelae of SARS CoV-2 infection (PASC), more commonly referred to as Long COVID, is one of the most daunting health-care grand challenges facing the United States today. Affecting millions of Americans, Long COVID extracts a huge cost both socially and economically. In this article, we provide a preliminary estimate of the annual income loss and medical costs due to Long COVID in the United States. With many Long COVID patients either meeting the diagnostic criteria for myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) or exhibiting symptoms consistent with ME/CFS, we utilize ME/CFS to help guide our estimates. Based on the nearly 86 million documented US COVID survivors as of June 25, 2022, and considering a range of 5% to 20% of those survivors currently afflicted with Long COVID, we estimate annual medical costs to range from $43 billion to $172 billion, and lost income to range from $101 billion to $430 billion. This corresponds to an annual economic impact (exclusive of costs of disability services, social services, and lost income on the part of caretakers) ranging from roughly $140 billion to $600 billion.

Source: Arthur A. Mirin (2022) A preliminary estimate of the economic impact of long COVID in the United States, Fatigue: Biomedicine, Health & Behavior, DOI: 10.1080/21641846.2022.2124064

Understanding myalgic encephalomyelitis

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a severe condition characterized by post-exertional neuroimmune exhaustion (PENE) accompanied by neurological, immunological, gastrointestinal (GI), and mitochondrial disturbances (1). The global prevalence of ME/CFS is ∼1%, affecting 17 million to 24 million people (2). ME/CFS is heterogeneous not only in symptom presentation but also illness trajectories, which can be worsening, plateauing, improving, or relapsing-remitting. Approximately 25% of patients with ME/CFS are considered severe and are bound to their homes. Although the etiology of ME/CFS is elusive, a large proportion of patients (∼60%) report post-infectious onset, such as after Epstein-Barr virus infection (3). The recent emergence of a chronic post-infectious condition, called Long Covid, overlaps considerably with ME/CFS in immunological, mitochondrial, and neurological dysfunctions (4). These similarities have resulted in increased interest and acceptance of ME/CFS as a disease and may stimulate research, the development of a diagnostic test, and pharmacotherapeutic interventions in ME/CFS that may be applied to Long Covid.

Read the rest of this article HERE.

Source: Sonya Marshall-Gradisnik and Natalie Eaton-Fitch. Understanding myalgic encephalomyelitis. SCIENCE, 8 Sep 2022, Vol 377, Issue 6611, pp. 1150-1151, DOI: 10.1126/science.abo126 https://www.science.org/doi/10.1126/science.abo1261 (Full text)

Lots of long COVID treatment leads, but few are proven

As the current crisis phase of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic winds down—and the world nervously awaits potentially dangerous new variants—research into the nature and treatment of so-called long coronavirus disease (COVID) is beginning to ramp up. The White House has promised funding and a federal research roadmap, and dedicated clinics have started cropping up at academic medical centers across the country.

But attempts to understand and treat long COVID have been underway almost since the pandemic began. For more than 2 years, clinicians have been coping—mostly on their own—with streams of patients complaining of persistent symptoms or mysterious new ones after a bout with COVID-19 had seemingly resolved ( 1 ). And collectively, doctors and researchers have already made headway toward identifying some of the mechanisms underlying the condition—formally known as post-acute sequelae of COVID (PASC).

Read the rest of this article HERE.

Source: Leah Shaffer. Lots of long COVID treatment leads, but few are proven. Vol. 119 | No. 36. https://www.pnas.org/doi/10.1073/pnas.2213524119 (Full text)

The Advantages of an Integrative Approach in the Primary Healthcare of Post-COVID-19 and ME/CFS Patients

Abstract:

The coronavirus disease caused by the SARS-CoV-2 virus (COVID-19) pandemic has changed not only global epidemiological and economic developments but also the lives of every individual, with particular severity for patients.

The number of acute illness cases grew rapidly, significantly increasing the workload of hospitals, and simultaneously, new chronic diseases emerged, such as persistent post-COVID-19 syndrome (PPCS), with unclear etiology, symptoms, and complexity—similar to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

Accordingly, the burden of chronic diseases poses new long-term challenges for primary healthcare and requires new approaches to patient care.

This chapter provides insight into the integrative approach to healthcare and focuses on potentially new solutions by implementing an integrative attitude to the treatment of post-COVID-19 and ME/CFS patients in primary healthcare.

Integrative health coaching contributes the holistic approach to patients’ overall health and resilience through cognitive practice and patient active engagement. The findings of this chapter can enrich the person-centered approach and healthcare system strengthening through holistic measures and systems thinking.

Source: Diana Araja, Angelika Krumina, Uldis Berkis, Zaiga Nora-Krukle and Modra Murovska. The Advantages of an Integrative Approach in the Primary Healthcare of Post-COVID-19 and ME/CFS Patients. DOI: 10.5772/intechopen.106013  https://www.intechopen.com/online-first/82708 (Full text)

A prospective observational study of post-COVID-19 chronic fatigue syndrome following the first pandemic wave in Germany and biomarkers associated with symptom severity

Abstract:

A subset of patients has long-lasting symptoms after mild to moderate Coronavirus disease 2019 (COVID-19). In a prospective observational cohort study, we analyze clinical and laboratory parameters in 42 post-COVID-19 syndrome patients (29 female/13 male, median age 36.5 years) with persistent moderate to severe fatigue and exertion intolerance six months following COVID-19. Further we evaluate an age- and sex-matched postinfectious non-COVID-19 myalgic encephalomyelitis/chronic fatigue syndrome cohort comparatively.

Most post-COVID-19 syndrome patients are moderately to severely impaired in daily live. 19 post-COVID-19 syndrome patients fulfill the 2003 Canadian Consensus Criteria for myalgic encephalomyelitis/chronic fatigue syndrome. Disease severity and symptom burden is similar in post-COVID-19 syndrome/myalgic encephalomyelitis/chronic fatigue syndrome and non-COVID-19/myalgic encephalomyelitis/chronic fatigue syndrome patients. Hand grip strength is diminished in most patients compared to normal values in healthy.

Association of hand grip strength with hemoglobin, interleukin 8 and C-reactive protein in post-COVID-19 syndrome/non-myalgic encephalomyelitis/chronic fatigue syndrome and with hemoglobin, N-terminal prohormone of brain natriuretic peptide, bilirubin, and ferritin in post-COVID-19 syndrome/myalgic encephalomyelitis/chronic fatigue syndrome may indicate low level inflammation and hypoperfusion as potential pathomechanisms.

Source: Kedor C, Freitag H, Meyer-Arndt L, Wittke K, Hanitsch LG, Zoller T, Steinbeis F, Haffke M, Rudolf G, Heidecker B, Bobbert T, Spranger J, Volk HD, Skurk C, Konietschke F, Paul F, Behrends U, Bellmann-Strobl J, Scheibenbogen C. A prospective observational study of post-COVID-19 chronic fatigue syndrome following the first pandemic wave in Germany and biomarkers associated with symptom severity. Nat Commun. 2022 Aug 30;13(1):5104. doi: 10.1038/s41467-022-32507-6. PMID: 36042189. https://www.nature.com/articles/s41467-022-32507-6 (Full text)

Transient receptor potential melastatin 3 dysfunction in post COVID-19 condition and myalgic encephalomyelitis/chronic fatigue syndrome patients

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a severe multisystemic condition associated with post-infectious onset, impaired natural killer (NK) cell cytotoxicity and impaired ion channel function, namely Transient Receptor Potential Melastatin 3 (TRPM3). Long-term effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has resulted in neurocognitive, immunological, gastrointestinal, and cardiovascular manifestations recently recognised as post coronavirus disease 2019 (COVID-19) condition. The symptomatology of ME/CFS overlaps significantly with post COVID-19; therefore, this research aimed to investigate TRPM3 ion channel function in post COVID-19 condition patients.

Methods: Whole-cell patch-clamp technique was used to measure TRPM3 ion channel activity in isolated NK cells of N = 5 ME/CFS patients, N = 5 post COVID-19 patients, and N = 5 healthy controls (HC). The TRPM3 agonist, pregnenolone sulfate (PregS) was used to activate TRPM3 function, while ononetin was used as a TRPM3 antagonist.

Results: As reported in previous research, PregS-induced TRPM3 currents were significantly reduced in ME/CFS patients compared with HC (p = 0.0048). PregS-induced TRPM3 amplitude was significantly reduced in post COVID-19 condition compared with HC (p = 0.0039). Importantly, no significant difference was reported in ME/CFS patients compared with post COVID-19 condition as PregS-induced TRPM3 currents of post COVID-19 condition patients were similar of ME/CFS patients currents (p > 0.9999). Isolated NK cells from post COVID-19 condition and ME/CFS patients were resistant to ononetin and differed significantly with HC (p < 0.0001).

Conclusion: The results of this investigation suggest that post COVID-19 condition patients may have impaired TRPM3 ion channel function and provide further evidence regarding the similarities between post COVID-19 condition and ME/CFS. Impaired TRPM3 channel activity in post COVID-19 condition patients suggest impaired ion mobilisation which may consequently impede cell function resulting in chronic post-infectious symptoms. Further investigation into TRPM3 function may elucidate the pathomechanism, provide a diagnostic and therapeutic target for post COVID-19 condition patients and commonalities with ME/CFS patients.

Source: Sasso EM, Muraki K, Eaton-Fitch N, Smith P, Lesslar OL, Deed G, Marshall-Gradisnik S. Transient receptor potential melastatin 3 dysfunction in post COVID-19 condition and myalgic encephalomyelitis/chronic fatigue syndrome patients. Mol Med. 2022 Aug 19;28(1):98. doi: 10.1186/s10020-022-00528-y. PMID: 35986236.  https://molmed.biomedcentral.com/articles/10.1186/s10020-022-00528-y (Full text)