The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications

Abstract:

Ischaemia-reperfusion (I-R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I-R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID.

Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities.

Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.

Source: Kell DB, Pretorius E. The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications. Biochem J. 2022 Aug 31;479(16):1653-1708. doi: 10.1042/BCJ20220154. PMID: 36043493. https://portlandpress.com/biochemj/article/479/16/1653/231696/The-potential-role-of-ischaemia-reperfusion-injury (Full text)

Cardiac impairments in postacute COVID-19 with sustained symptoms: A review of the literature and proof of concept

Abstract:

Although acute COVID-19 is known to cause cardiac damage in some cases, there is still much to learn about the duration and relative permanence of the damage that may occur. Long COVID is a condition that can occur when COVID-19 symptoms remain in the postviral acute period. Varying accounts of long COVID have been described across the literature, however, cardiac impairments are sustained in many individuals and cardiovascular assessment is now considered to be an expected follow-up examination.

The purpose of this review and proof of concept is to summarize the current research related to the assessment of cardiac function, including echocardiography and blood biomarker data, during the follow-up period in patients who recovered from COVID-19. Following a literature review, it was found that right ventricular dysfunction along with global longitudinal strain and diastolic dysfunction are common findings.

Finally, more severe acute myocardial injury during the index hospitalization appears to exacerbate cardiac function. The available literature implies that cardiac function must be monitored in patients recovered from COVID-19 who remain symptomatic and that the impairments and severity vary from person-to-person.

The proof-of-concept analysis of patients with cardiac disease and respiratory disease in comparison to those with sustained symptoms from COVID-19 suggests elevated systolic time interval in those with sustained symptoms from COVID-19, thus reducing heart performance indices. Future research must consider the details of cardiac complications during the acute infection period and relate this to the cardiac function in patients with long COVID during mid- and long-term follow-up.

Source: Singh J, Bhagaloo L, Sy E, Lavoie AJ, Dehghani P, Bardutz HA, Mang CS, Buttigieg J, Neary JP. Cardiac impairments in postacute COVID-19 with sustained symptoms: A review of the literature and proof of concept. Physiol Rep. 2022 Aug;10(16):e15430. doi: 10.14814/phy2.15430. PMID: 35993433; PMCID: PMC9393908.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9393908/ (Full text)

NeuroCOVID-19: a critical review

Abstract:

Background: The COVID-19 pandemic has challenged neurologists since its early days. Neurology consultation services were then overloaded by emergency department and intensive-care patients with acute neurological syndromes. These complications are better explained today, but the growing number of patients with reported longstanding neurological symptoms constitute an emerging, complex, and still poorly understood phenomenon.

Objective: This review summarizes data on relevant neurological manifestations of acute SARS-CoV-2 infection and lasting post-infectious disease, also known as Long COVID. The complex history of Long COVID is examined to illustrate the upsides and challenges imposed by the active participation of patient communities in the production of medical knowledge.

Methods: Narrative review.

Results: Infection with the severe acute respiratory syndrome coronavirus 2 is associated with encephalopathy/delirium, cerebrovascular disease, headache, and peripheral nervous system involvement. Long COVID is a living concept jointly defined by patient communities, physicians and scientists, including neurologists.

Conclusion: Co-production of Long COVID knowledge between scientists and patients has initiated an era of patient-led research and evidence-based activism that acts as a two-edged sword – putting patient’s suffering in the spotlight, but with a tradeoff in methodological consistency.

Source: Guedes BF. NeuroCOVID-19: a critical review. Arq Neuropsiquiatr. 2022 May;80(5 Suppl 1):281-289. doi: 10.1590/0004-282X-ANP-2022-S136. PMID: 35976326. https://www.scielo.br/j/anp/a/v6c3Xcvq4PkkD3HvKtT7DJN/?lang=en  (Full tex)

Myalgic encephalomyelitis/chronic fatigue syndrome and pregnancy: A mixed-methods systematic review

Abstract:

Background Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a fluctuating complex condition. More common in women than men, it tends to develop between mid-20s and mid-40s, including the main childbearing age (15–45 years). There are currently no systematic reviews summarising evidence relating to ME/CFS and pregnancy. The lack of quality assessed, and systematic summary evidence makes it harder for people with ME/CFS to make informed decisions about pregnancy, and harder for health care professionals to offer evidence-based care. This mixed methods systematic review aims to examine and summarise existing evidence relating to ME/CFS and pregnancy, both in relation to pregnancy outcomes and experiences of pregnancy but also the effect of pregnancy on ME/CFS severity and symptoms.

Methods This review followed a convergent segregated design. Seven electronic databases, relevant grey literature, reference lists of relevant reviews, and reference lists and citations of all included studies, were searched. Where necessary, authors were contacted for additional information. Studies of any design published in English, reporting on ME/CFS and pregnancy/postpartum (up to two years), risk of pregnancy outcomes with ME/CFS, or experiences during pregnancy for mother, partner or health and social care professionals following pregnancy with ME/CFS were included. Three researchers performed screening, data extraction and quality assessments independently. Qualitative and quantitative literature was analysed separately using thematic and descriptive syntheses, respectively (meta-analysis was not appropriate). Findings were integrated through configuration.

Results Searches identified n=2,789 studies, n=10 met our inclusion criteria. There were five quantitative studies, two qualitative studies and three pieces of grey literature. Preliminary results suggest that evidence is conflicting. In the qualitative literature, one study suggested one participant thought pregnancy improved ME/CFS symptoms while the other noted a participant commented that ME/CFS may have adversely affected her pregnancy. Of the four quantitative studies that reported on ME severity during pregnancy, two suggested pregnancy negatively impacted on ME/CFS, one study found most women had no change in ME/CFS symptoms during pregnancy, and one found ME/CFS improved during pregnancy. Only one study reported on pregnancy outcomes, finding a higher rate of spontaneous abortions, and increased developmental and learning delays in infants born to mothers with ME/CFS.

Conclusion Current evidence on ME/CFS in pregnancy is limited, and findings are inconsistent. Studies are limited by small sample size and currently, there is no UK evidence. More high-quality research into ME/CFS and pregnancy is urgently needed to support the development of evidence-based guidelines on ME/CFS and pregnancy.

Source: Pearce M, Slack E, Pears K, et alOP72 Myalgic encephalomyelitis/chronic fatigue syndrome and pregnancy: a mixed-methods systematic reviewJ Epidemiol Community Health 2022;76:A35. https://jech.bmj.com/content/76/Suppl_1/A35.1

Fatigue in ANCA-associated vasculitis (AAV) and systemic sclerosis (SSc): similarities with Myalgic encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). A critical review of the literature

Abstract:

Introduction: Persistent debilitating fatigue is a frequent complaint in patients with systemic autoimmune rheumatic diseases (SARDs). Fatigue is, however, frequently overlooked in the clinic, and patients who successfully achieve remission of their disease, often still have a lowered quality of life due to its persistence. How similar is this fatigue to Myalgic encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), what is this fatigue associated with, and what tools/approaches (if any), have resulted in the improvement of fatigue in these patients is poorly defined.

Areas covered: Similarities between the pathophysiology of ME/CFS, systemic sclerosis (SSc) and primary systemic vasculitides (PSV) are discussed, followed by an in-depth review of the prevalence and correlates of fatigue in these diseases. The authors reviewed literature from MEDLINE, APA PsycInfo, Embase, and CINAHL.

Expert opinion: Persistent fatigue is a prominent feature in SARDs and may not be associated with components commonly associated with disease activity and/or progression. Immune and metabolic commonalities exist between ME/CFS, SSc, and PSVs – suggesting that common pathways inherent to the diseases and fatigue may be present. We suggest that patients with features of ME/CFS need to be identified by treating physicians, as they may require alternative approaches to therapy to improve their quality of life.

Source: van Eeden C, Osman MS, Cohen Tervaert JW. Fatigue in ANCA-associated vasculitis (AAV) and systemic sclerosis (SSc): similarities with Myalgic encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). A critical review of the literature. Expert Rev Clin Immunol. 2022 Aug 31:1-22. doi: 10.1080/1744666X.2022.2116002. Epub ahead of print. PMID: 36045606. https://pubmed.ncbi.nlm.nih.gov/36045606/

Autoimmune Autonomic Dysfunction Syndromes: Potential Involvement and Pathophysiology Related to Complex Regional Pain Syndrome, Fibromyalgia, Chronic Fatigue Syndrome, Silicone Breast Implant-Related Symptoms and Post-COVID Syndrome

Abstract:

The pathophysiological mechanisms involved in chronic disorders such as complex regional pain syndrome, fibromyalgia, chronic fatigue syndrome, silicone breast implant-related symptoms, and post-COVID syndrome have not been clearly defined. The course of the pain in some of the syndromes, the absence of evident tissue damage, and the predominance of alterations in the autonomic nervous system are shared similarities between them.

The production of autoantibodies following a trigger in the syndromes was previously described, for instance, trauma in complex regional pain syndrome, infectious agents in fibromyalgia, chronic fatigue syndrome, and post-COVID syndrome, and the immune stimulation by silicone in women with breast implants. In fact, the autoantibodies produced were shown to be directed against the autonomic nervous system receptors, leading to the amplification of the perception of pain alongside various clinical symptoms seen during the clinical course of the syndromes. Therefore, we viewed autoantibodies targeting the autonomic nervous system resulting in autonomic dysfunction as likely the most comprehensive explanation of the pathophysiology of the disorders mentioned.

Based on this, we aimed to introduce a new concept uniting complex regional pain syndrome, fibromyalgia, chronic fatigue syndrome, silicone breast implant-related symptoms, and post-COVID syndrome, namely “autoimmune autonomic dysfunction syndromes”. Due to its etiological, pathophysiological, and clinical implications, the suggested term would be more precise in classifying the syndromes under one title. The new title would doubtlessly facilitate both laboratory and clinical studies aimed to improve diagnosis and make treatment options more directed and precise.

Source: Mahroum N, Shoenfeld Y. Autoimmune Autonomic Dysfunction Syndromes: Potential Involvement and Pathophysiology Related to Complex Regional Pain Syndrome, Fibromyalgia, Chronic Fatigue Syndrome, Silicone Breast Implant-Related Symptoms and Post-COVID Syndrome. Pathophysiology. 2022 Jul 28;29(3):414-425. doi: 10.3390/pathophysiology29030033. PMID: 35997389. https://www.mdpi.com/1873-149X/29/3/33/htm (Full text)

Coenzyme Q10 + alpha lipoic acid for chronic COVID syndrome

Abstract:

Chronic COVID syndrome is characterized by chronic fatigue, myalgia, depression and sleep disturbances, similar to chronic fatigue syndrome (CFS) and fibromyalgia syndrome. Implementations of mitochondrial nutrients (MNs) with diet are important for the clinical effects antioxidant. We examined if use of an association of coenzyme Q10 and alpha lipoic acid (Requpero®) could reduce chronic covid symptoms.

The Requpero study is a prospective observational study in which 174 patients, who had developed chronic-covid syndrome, were divided in two groups: The first one (116 patients) received coenzyme Q10 + alpha lipoic acid, and the second one (58 patients) did not receive any treatment. Primary outcome was reduction in Fatigue Severity Scale (FSS) in treatment group compared with control group. complete FSS response was reached most frequently in treatment group than in control group. A FSS complete response was reached in 62 (53.5%) patients in treatment group and in two (3.5%) patients in control group. A reduction in FSS core < 20% from baseline at T1 (non-response) was observed in 11 patients in the treatment group (9.5%) and in 15 patients in the control group (25.9%) (p < 0.0001).

To date, this is the first study that tests the efficacy of coenzyme Q10 and alpha lipoic acid in chronic Covid syndrome. Primary and secondary outcomes were met. These results have to be confirmed through a double blind placebo controlled trial of longer duration.

Source: Barletta MA, Marino G, Spagnolo B, Bianchi FP, Falappone PCF, Spagnolo L, Gatti P. Coenzyme Q10 + alpha lipoic acid for chronic COVID syndrome. Clin Exp Med. 2022 Aug 22. doi: 10.1007/s10238-022-00871-8. Epub ahead of print. PMID: 35994177.  https://link.springer.com/article/10.1007/s10238-022-00871-8 (Full text)

Complementary and Alternative Medicine for Long COVID: Scoping Review and Bibliometric Analysis

Abstract:

Prolonged symptoms after the clearance of acute coronavirus disease 2019 (COVID-19) infection, termed long COVID, are an emerging threat to the post-COVID-19 era. Complementary and alternative medicine (CAM) interventions may play a significant role in the management of long COVID. The present study aimed to identify published studies on the use of CAM interventions for long COVID and provide an overview of the research status using bibliometric analysis.

The present scoping review searched MEDLINE, Embase, and Cochrane Library from inception until November 2021 and identified published studies on CAM interventions for long COVID. A narrative analysis of the study types and effectiveness and safety of the CAM interventions are presented and a bibliometric analysis of citation information and references of the included publications were analyzed using the Bibliometrix package for R. An electronic database search identified 16 publications (2 clinical studies and 14 study protocols of systematic reviews or clinical studies) that were included in the present study. Dyspnea or pulmonary dysfunction, quality of life, olfactory dysfunction, and psychological symptoms after COVID-19 infection were assessed in the included publications.

The two clinical studies suggested that Chinese herbal medications were effective in relieving symptoms of pulmonary dysfunction. Bibliometric analysis revealed the current trend of research publication in this area was driven by study protocols written by Chinese, Korean, and Indian authors. Thus, the present scoping review and bibliometric analysis revealed that there are few studies published about the use of CAM for long COVID and long-term management for COVID-19 survivors. Original studies on CAM interventions, including randomized controlled trials and systematic reviews, are required to actively support evidence for their use in the management of long COVID. PROSPERO registration: this trial is registered with CRD42021281526.

Source: Tae-Hun Kim, Sae-Rom Jeon, Jung Won Kang, Sunoh Kwon, “Complementary and Alternative Medicine for Long COVID: Scoping Review and Bibliometric Analysis“, Evidence-Based Complementary and Alternative Medicine, vol. 2022, Article ID 7303393, 7 pages, 2022. https://doi.org/10.1155/2022/7303393 https://www.hindawi.com/journals/ecam/2022/7303393/ (Full text)

A Review of Respiratory Post-Acute Sequelae of COVID-19 (PASC) and the Potential Benefits of Pulmonary Rehabilitation

Abstract:

With the SARS-CoV-2 pandemic continuing into its third year, the number of patients who survive acute COVID-19 infection but go on to develop long-term symptoms is increasing daily. Those individuals who experience one or more of a variety of persistent symptoms post-COVID-19 are now diagnosed with the syndrome called post-acute sequelae of COVID-19 (PASC), often colloquially called “Long COVID.” This article discusses relevant research and current hypotheses regarding the pathophysiology and management of respiratory symptoms of PASC, in order to provide primary care physicians with context for management of this heterogeneous population. We focus on the growing body of research that supports the use of pulmonary rehabilitation for patients with PASC to improve symptoms and quality of life.

Source: Simon M, Simmons JE. A Review of Respiratory Post-Acute Sequelae of COVID-19 (PASC) and the Potential Benefits of Pulmonary Rehabilitation. R I Med J (2013). 2022 Sep 1;105(7):11-15. PMID: 35930484.  https://pubmed.ncbi.nlm.nih.gov/35930484/ http://rimed.org/rimedicaljournal/2022/09/2022-09-11-covid-simon.pdf (Full text available as PDF file)

Post-COVID syndrome with fatigue and exercise intolerance: myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Background: A sizable part of post-COVID syndrome meets the diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). A doubling of cases of ME/CFS within the next years is therefore projected.

Objectives: Presentation of the current state of knowledge on ME/CFS.

Materials and methods: Unsystematic review of the literature and of own contributions in research and patient care.

Results and conclusions: ME/CFS is a neuroimmunological disease, mostly infection-induced, usually persisting throughout life. Clinically it is characterized by fatigue lasting at least 6 months and the defining core feature of exercise intolerance (post-exertional malaise, PEM). Exercise intolerance is defined as a worsening of symptoms after (even mild) everyday exertion, which usually begins after several hours or on the following day, is still noticeable at least 14 h after exertion, and often lasts for several days (up to weeks or longer). Furthermore, ME/CFS is characterized by pain, disturbances of sleep, thinking and memory, and dysregulation of the circulatory, endocrine, and immune systems.

As a separate clinical entity, ME/CFS should be distinguished from chronic fatigue, which occurs as a symptom of a range of very different diseases. The diagnosis of ME/CFS is made clinically using established international diagnostic criteria and requires careful stepwise diagnosis to exclude other diagnoses. A causal therapy for ME/CFS has not been established; the focus is on symptoms relief, treatment of the often accompanying orthostatic intolerance, and assistance with anticipatory energy management (pacing).

Source: Renz-Polster H, Scheibenbogen C. Post-COVID-Syndrom mit Fatigue und Belastungsintoleranz: Myalgische Enzephalomyelitis bzw. Chronisches Fatigue-Syndrom [Post-COVID syndrome with fatigue and exercise intolerance: myalgic encephalomyelitis/chronic fatigue syndrome]. Inn Med (Heidelb). 2022 Aug;63(8):830-839. German. doi: 10.1007/s00108-022-01369-x. Epub 2022 Jul 13. PMID: 35925074. https://pubmed.ncbi.nlm.nih.gov/35925074/  https://link.springer.com/article/10.1007/s00108-022-01369-x (Full text in German)