Tag: long covid vs ME/CFS

On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection

Introduction:

There is an increasing body of evidence connecting the post-acute SARS-CoV-2 condition (PASC, commonly known as long COVID) to Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a debilitating disease of unknown cause characterized by persistent and unexplained fatigue, post-exertional malaise (PEM), among other symptoms. This connection implies that, in the clinic, some PASC cases comply with the official case definitions of ME/CFS. As such, there is a necessity to quantify the burden of ME/CFS among the PASC population in order to delineate effective healthcare interventions for the benefit of these patients who are often neglected or, in some extreme cases, stigmatized by medical staff and society.
To answer this urgent research question, Dehlia and Guthridge performed a systematic review and meta-analysis of recent data on PASC adults and reported an ME/CFS prevalence estimate of 51% (95% CI, 42%-60%); this systematic review and meta-analysis will be referred to as PASC-ME/CFS study. In the present Letter to Editor, we aimed to discuss the reliability of this estimate using the research protocol from the European Network on ME/CFS (EUROMENE) for systematic reviews and meta-analysis on the epidemiology burden of ME/CFS in Europe.

Source: Sepúlveda N, Westermeier F. On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection. J Infect. 2024 Nov 16:106353. doi: 10.1016/j.jinf.2024.106353. Epub ahead of print. PMID: 39557089. Sepúlveda N, Westermeier F. On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection. J Infect. 2024 Nov 16:106353. doi: 10.1016/j.jinf.2024.106353. Epub ahead of print. PMID: 39557089. https://www.journalofinfection.com/article/S0163-4453(24)00288-3/fulltext (Full text)

Blood virome research in myalgic encephalomyelitis/chronic fatigue syndrome: challenges and opportunities

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating disease with a complex clinical presentation and an unknown etiology. Various viral infections have been proposed as potential triggers of ME/CFS onset, but no specific pathogen has been identified in all cases of postinfectious ME/CFS.

The symptomatology of the postacute sequelae of SARS-CoV-2, or long COVID, mirrors that of ME/CFS, with nearly half of long COVID patients meeting ME/CFS diagnostic criteria. The influx of newly diagnosed patients has reinvigorated interest in ME/CFS pathogenesis research, with an emphasis on viral triggers.

This review summarizes the current understanding of ME/CFS research on viral triggers, including blood virome screening studies. To further elucidate the molecular basis of ME/CFS, there is a need to develop innovative bioinformatics tools capable of analyzing complex virome data and integrating multiomics information.

Source: Obraitis D, Li D. Blood virome research in myalgic encephalomyelitis/chronic fatigue syndrome: challenges and opportunities. Curr Opin Virol. 2024 Nov 12:101437. doi: 10.1016/j.coviro.2024.101437. Epub ahead of print. PMID: 39537445. https://www.sciencedirect.com/science/article/pii/S1879625724000518 (Full text)

Overlapping conditions in Long COVID at a multisite academic center

Abstract:

Background: Many patients experience persistent symptoms after COVID-19, a syndrome referred to as Long COVID (LC). The goal of this study was to identify novel new or worsening comorbidities self-reported in patients with LC.

Methods: Patients diagnosed with LC (n = 732) at the Mayo Long COVID Care Clinic in Rochester, Minnesota and Jacksonville, Florida were sent questionnaires to assess the development of new or worsening comorbidities following COVID-19 compared to patients with SARS-CoV-2 that did not develop LC (controls). Both groups were also asked questions screening for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), generalized joint hypermobility (GJH) and orthostatic intolerance. 247 people with LC (33.7%) and 40 controls (50%) responded to the surveys.

Results: In this study LC patients averaged 53 years of age and were predominantly White (95%) women (75%). The greatest prevalence of new or worsening comorbidities following SARS-CoV-2 infection in patients with LC vs. controls reported in this study were pain (94.4% vs. 0%, p < 0.001), neurological (92.4% vs. 15.4%, p < 0.001), sleep (82.8% vs. 5.3%, p < 0.001), skin (69.8% vs. 0%, p < 0.001), and genitourinary (60.6% vs. 25.0%, p = 0.029) issues. 58% of LC patients screened positive for ME/CFS vs. 0% of controls (p < 0.001), 27% positive for GJH compared to 10% of controls (p = 0.026), and a positive average score of 4.0 on orthostatic intolerance vs. 0 (p < 0.001). The majority of LC patients with ME/CFS were women (77%).

Conclusion: We found that comorbidities across 12 surveyed categories were increased in patients following SARS-CoV-2 infection. Our data also support the overlap of LC with ME/CFS, GJH, and orthostatic intolerance. We discuss the pathophysiologic, research, and clinical implications of identifying these conditions with LC.

Source: Grach SL, Dudenkov DV, Pollack B, Fairweather D, Aakre CA, Munipalli B, Croghan IT, Mueller MR, Overgaard JD, Bruno KA, Collins NM, Li Z, Hurt RT, Tal MC, Ganesh R, Knight DTR. Overlapping conditions in Long COVID at a multisite academic center. Front Neurol. 2024 Oct 25;15:1482917. doi: 10.3389/fneur.2024.1482917. PMID: 39524912; PMCID: PMC11543549. https://pmc.ncbi.nlm.nih.gov/articles/PMC11543549/ (Full text)

Stroop task and practice effects demonstrate cognitive dysfunction in long COVID and myalgic encephalomyelitis / chronic fatigue syndrome

Abstract:

Background: The Stroop task was used to investigate differences in cognitive function between Long COVID (LC), Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS) and healthy control subjects.

Methods: Subjects viewed four color words or neutral (XXXX) stimuli with the same (congruent) or different color ink (incongruent). Cognitive conflict was inferred from response times for pairings of prestimuli and subsequent stimuli. Overall effects were assessed by univariate analysis with time courses determined for binned response times.

Results: LC and ME/CFS had significantly longer response times than controls indicating cognitive dysfunction. Initial response times were ranked LC > ME > HC, and decreased according to power functions. At the end of the task (900s), times were ranked LC = ME > HC. Response times were significantly slower for stimuli following an incongruent prestimulus. Time series for Stroop effect, facilitation, interference, surprise index and practice power law parameters were generally similar in LC, ME/CFS and HC suggesting comparable patterns for recruitment of cognitive resources. The prestimulus data were analyzed and generated positive Stroop and interference effects that were distinct from stimulus effects.

Conclusion: LC and ME/CFS have global slowing of response times that cannot be overcome by practice suggesting impaired communications between network nodes during problem solving. Analysis of matched prestimulus – stimulus effects adds a new dimension for understanding cognitive conflict.

Brief summary: Cognitive dysfunction in Long COVID and ME/CFS was demonstrated using the Stroop task which found global slowing of response times and limitations of practice effects.

Source: Baraniuk JN, Thapaliya K, Inderyas M, Shan ZY, Barnden LR. Stroop task and practice effects demonstrate cognitive dysfunction in long COVID and myalgic encephalomyelitis / chronic fatigue syndrome. Sci Rep. 2024 Nov 5;14(1):26796. doi: 10.1038/s41598-024-75651-3. PMID: 39500939; PMCID: PMC11538523. https://pmc.ncbi.nlm.nih.gov/articles/PMC11538523/ (Full text)

Assessment of the therapeutic potential of salubrinal for ME/CFS and long-COVID

Highlights:

  • Long-COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are enigmatic diseases sharing many characteristics.
  • The most debilitating aspects of these diseases are cognitive dysfunction, ‘brain fog’, and exercise intolerance, ‘post-exertional malaise’.
  • There is no cure for these diseases; treatment is palliative only.
  • Mitochondrial dysfunction with endoplasmic reticulum (ER) stress occurs in both diseases.
  • Salubrinal inhibits the phosphatase that dephosphorylates phospho-eukaryotic initiation factor-2α (peIF2α), a protective protein for cells undergoing ER stress when phosphorylated.
  • Salubrinal reduces the formation of Wiskott–Aldrich syndrome protein family member 3 (WASF3), a protein that causes mitochondrial dysfunction that is overexpressed in a cohort of ME/CFS patients.
  • Salubrinal reduces WASF3 expression, restoring mitochondrial function in fibroblasts of a patient with ME/CFS.

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic debilitating condition with no cure that shares commonality with long-COVID.

This review examines current understanding of long-COVID symptoms, characteristics of the affected population, the connection with ME/CFS, and the potential for salubrinal, an agent known for its influence on cellular stress pathways, to mitigate these disorders.

It also describes the historical development and mechanism of action of salubrinal, to mitigate endoplasmic reticulum (ER)/cellular stress responses, that could potentially contribute to symptom improvement in both ME/CFS and long-COVID patients.

Further research and clinical trials are warranted to advance our understanding of the potential role of salubrinal in improving the quality of life for individuals with long-COVID-related ME/CFS symptoms as well as ME/CFS patients.

Source: Aseel Warrayat, Ayah Ali, Joulin Waked, Darcy Tocci, Robert C. Speth. Assessment of the therapeutic potential of salubrinal for ME/CFS and long-COVID. Trends in Molecular Medicine, 2024. ISSN 1471-4914, https://doi.org/10.1016/j.molmed.2024.10.001. https://www.sciencedirect.com/science/article/abs/pii/S1471491424002685

Immune exhaustion in ME/CFS and long COVID

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and long COVID are debilitating multisystemic conditions sharing similarities in immune dysregulation and cellular signaling pathways contributing to the pathophysiology. In this study, immune exhaustion gene expression was investigated in participants with ME/CFS or long COVID concurrently.

RNA was extracted from peripheral blood mononuclear cells isolated from participants with ME/CFS (n = 14), participants with long COVID (n = 15), and healthy controls (n = 18). Participants with ME/CFS were included according to Canadian Consensus Criteria. Participants with long COVID were eligible according to the case definition for “Post COVID-19 Condition” published by the World Health Organization. RNA was analyzed using the NanoString nCounter Immune Exhaustion gene expression panel.

Differential gene expression analysis in ME/CFS revealed downregulated IFN signaling and immunoglobulin genes, and this suggested a state of immune suppression. Pathway analysis implicated dysregulated macrophage activation, cytokine production, and immunodeficiency signaling.

Long COVID samples exhibited dysregulated expression of genes regarding antigen presentation, cytokine signaling, and immune activation. Differentially expressed genes were associated with antigen presentation, B cell development, macrophage activation, and cytokine signaling.

This investigation elucidates the intricate role of both adaptive and innate immune dysregulation underlying ME/CFS and long COVID, emphasizing the potential importance of immune exhaustion in disease progression.

Source: Natalie Eaton-Fitch, Penny Rudd, Teagan Er, Livia Hool, Lara Herrero, and Sonya Marshall-Gradisnik. Immune exhaustion in ME/CFS and long COVID. JCI Insight. 2024;9(20):e183810. https://doi.org/10.1172/jci.insight.183810. https://insight.jci.org/articles/view/183810 (Full text)

A review of intravenous immunoglobulin in the treatment of neuroimmune conditions, acute COVID-19 infection, and post-acute sequelae of COVID-19 Syndrome

Abstract:

Intravenous immunoglobulin (IVIG) is an immunomodulatory therapy that has been studied in several neuroimmune conditions, such as Guillain-Barré Syndrome, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, and multiple sclerosis. It has also been proposed as a potential treatment option for acute COVID-19 infection and post-acute sequelae of SARS-CoV-2 infection (PASC). IVIG is thought to function by providing the recipient with a pool of antibodies, which can, in turn, modulate immune responses through multiple mechanisms including neutralization of cytokines and autoantibodies, saturation of neonatal fragment crystallizable receptors, inhibition of complement activation, and regulation of T and B cell mediated inflammation.

In acute COVID-19, studies have shown that early administration of IVIG and plasmapheresis in severe cases can reduce the need for mechanical ventilation, shorten ICU and hospital stays, and lower mortality. Similarly, in PASC, while research is still in early stages, IVIG has been shown to alleviate persistent symptoms in small patient cohorts.

Furthermore, IVIG has shown benefits in another condition which has symptomatic overlap with PASC, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), though studies have yielded mixed results. It is important to note that IVIG can be associated with several potential adverse effects, such as anaphylaxis, headaches, thrombosis, liver enzyme elevations and renal complications. In addition, the high cost of IVIG can be a deterrent for payers and patients.

This review provides a comprehensive update on the use of IVIG in multiple neuroimmune conditions, ME/CFS, acute COVID-19, and PASC, as well as covers its history, production, pricing, and mechanisms of action. We also identify key areas of future research, including the need to optimize the use of Ig product dosing, timing, and patient selection across conditions, particularly in the context of COVID-19 and PASC.

Source: Morse BA, Motovilov K, Michael Brode W, Michael Tee F, Melamed E. A review of intravenous immunoglobulin in the treatment of neuroimmune conditions, acute COVID-19 infection, and post-acute sequelae of COVID-19 Syndrome. Brain Behav Immun. 2024 Oct 8:S0889-1591(24)00648-2. doi: 10.1016/j.bbi.2024.10.006. Epub ahead of print. PMID: 39389388. https://www.sciencedirect.com/science/article/abs/pii/S0889159124006482

Inspiratory muscle training improves autonomic function in myalgic encephalomyelitis/chronic fatigue syndrome and post-acute sequelae of SARS-CoV-2: a pilot study

Abstract:

Post-acute sequelae of SARS-CoV-2 (PASC), or Long COVID, and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are debilitating post-viral conditions with many symptomatic overlaps, including exercise intolerance and autonomic dysfunction. Both conditions are growing in prevalence, and effective safe treatment strategies must be investigated. We hypothesized that inspiratory muscle training (IMT) could be used in PASC and mild to moderate ME/CFS to mitigate symptoms, improve exercise capacity, and improve autonomic function.

We recruited healthy controls (n=12; 10 women), people with PASC (n=9; 8 women), and people with mild to moderate ME/CFS (n=12; 10 women) to complete 8 weeks of IMT. This project was registered as a clinical trial (NCT05196529) with clinicaltrials.gov.

After completion of IMT, all groups experienced improvements in inspiratory muscle pressure (p<0.001), 6-minute walk distance (p=0.002), resting heart rate (p=0.037), heart rate variability (p<0.05), and symptoms related to sleep (p=0.009). In the ME/CFS group only, after completion of IMT, there were additional improvements with regard to vascular function (p=0.001), secretomotor function (p=0.023), the total weighted score (p=0.005) of the COMPASS 31 autonomic questionnaire, and symptoms related to pain (p=0.016).

We found that after 8 weeks of IMT, people with PASC and/or ME/CFS could see some overall improvements in their autonomic function and symptomology.

Source: Edgell H, Pereira TJ, Kerr K, Bray R, Tabassum F, Sergio L, Badhwar S. Inspiratory muscle training improves autonomic function in myalgic encephalomyelitis/chronic fatigue syndrome and post-acute sequelae of SARS-CoV-2: a pilot study. Respir Physiol Neurobiol. 2024 Oct 5:104360. doi: 10.1016/j.resp.2024.104360. Epub ahead of print. PMID: 39374820. https://www.sciencedirect.com/science/article/pii/S1569904824001538 (Full text)

Muscular metabolic plasticity in 3D in vitro models against systemic stress factors in ME/CFS and long COVID-19

Abstract:

Myalgic encephalomyelities/ chronic fatigue syndrome and long COVID-19 are clinically challenging, multi-symptomatic conditions with multiple overlapping symptoms. Unfortunately, contemporary research is directly being done on patients which risks exacerbating their symptoms. Using our 3-D in vitro skeletal muscle tissues we have mapped the progression of functional, physiological, and metabolic adaptations of the tissues in response to patient sera over time.

During short exposure we treated the tissues for 48 hours with patient sera. The contractile profiles of these tissues were severely compromised. Transcriptomic analyses of these short exposure samples showed an absence of significant differentially expressed genes between ME/CFS and LC-19. The analyses revealed an upregulation of glycolytic enzymes especially of PDK4, suggesting a switch away from Oxidative Phosphorylation as well as a decline in DRP1, involved in mitochondrial fission.

Subsequent structural analyses confirmed hypertrophy in myotubes and hyperfused mitochondrial networks. Mitochondrial oxygen consumption capacity, evaluated through the MitoStress test, was also elevated, as was the non-mitochondrial respiration confirming the shift to glycolysis.

Interestingly, at short exposures of 48 hours, the muscle tissues appeared to be adapting to the stress factors by upregulating glycolysis and increasing the muscular metabolic volume. Prolonging the exposure to 96 and 144 hours induced high fatiguability, and fragility in tissues. The mitochondria, at longer exposures, appeared to be fragmented and assumed a toroidal conformation indicating a change in mitochondrial membrane potential.

We hypothesize that the disease progresses through an intermediary stress-induced hypermetabolic state, ultimately leading to severe deterioration of muscle function. This is the first account of research that proposes acquired metabolic plasticity in 3D skeletal muscles exposed to ME/CFS and Long COVID-19 sera.

Source: S. Mughal, F. Andújar-Sánchez, M. Sabater-Arcis, J. Fernández-Costa, J. Ramón-Azcón. 571P Muscular metabolic plasticity in 3D in vitro models against systemic stress factors in ME/CFS and long COVID-19. Neuromuscular Disorders, Volume 43, Supplement 1, October 2024, 104441.162. https://www.sciencedirect.com/science/article/abs/pii/S0960896624003353

A pilot cross-sectional investigation of symptom clusters and associations with patient-reported outcomes in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post COVID-19 Condition

Abstract:

Background: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is associated with long-term disability and poor quality of life (QoL). Cardinal ME/CFS symptoms (including post-exertional malaise, cognitive dysfunction and sleep disturbances) have been observed in Post COVID-19 Condition (PCC). To gain further insight into the potential role of ME/CFS as a post-COVID-19 sequela, this study investigates associations between symptoms and patient-reported outcomes, as well as symptom clusters.
Methods: Participants included Australian residents aged between 18 and 65 years formally diagnosed with ME/CFS fulfilling the Canadian or International Consensus Criteria or PCC meeting the World Health Organization case definition. Validated, self-administered questionnaires collected participants’ sociodemographic and illness characteristics, symptoms, QoL and functional capacity. Associations between symptoms and patient-reported outcomes were investigated with multivariate linear regression models. Hierarchical cluster analysis was performed to identify symptom clusters.
Results: Most people with ME/CFS (pwME/CFS) and people with PCC (pwPCC) were female (n = 48/60, 80.0% and n = 19/30, 63.3%, respectively; p = 0.12). PwME/CFS were significantly younger (x̄=41.75, s = 12.91 years) than pwPCC (x̄=48.13, s =10.05 years; p =0.017). Autonomic symptoms (notably dyspnoea) were associated with poorer scores in most patient-reported outcome domains for both cohorts. None of the four symptom clusters identified were unique to ME/CFS or PCC. Clusters were largely delineated by the presence of gastrointestinal and neurosensory symptoms, illness duration, ME/CFS criteria met and total symptoms.
Conclusions: Illness duration may explain differences in symptom burden between pwME/CFS and pwPCC. PCC diagnostic criteria must be refined to distinguish pwPCC at risk of long-term ME/CFS-like illness and subsequently deliver necessary care and support.
Source: Weigel B, Eaton-Fitch N, Thapaliya K, Marshall-Gradisnik S. A pilot cross-sectional investigation of symptom clusters and associations with patient-reported outcomes in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Post COVID-19 Condition. Qual Life Res. 2024 Oct 3. doi: 10.1007/s11136-024-03794-x. Epub ahead of print. PMID: 39361124. https://link.springer.com/article/10.1007/s11136-024-03794-x (Full text)