Historical Insight into Infections and Disorders Associated with Neurological and Psychiatric Sequelae Similar to Long COVID

Abstract:

Long-term sequelae of coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are now recognized. However, there is still a lack of consensus regarding the terminology for this emerging chronic clinical syndrome, which includes long COVID, chronic COVID syndrome, post-COVID-19 syndrome, post-acute COVID-19, and long-hauler COVID-19. In this review, I will use the term “long COVID”. A review of the medical history and epidemiology of past pandemics and epidemics in modern literature review identifies common long-term post-infectious disorders, with the common finding of altered cognition.

In the brain, the cerebral hypoxia induced by SARS-CoV-2 infection may be caused by mitochondrial dysfunction, resulting in “brain fog”. Historically, the common symptom of altered cognition has been reported during earlier pandemics, which include the influenza pandemics of 1889 and 1892 (Russian flu), the Spanish flu pandemic (1918-1919), encephalitis lethargica, diphtheria, and myalgic encephalomyelitis (chronic fatigue syndrome or post-viral fatigue syndrome).

There are similarities between chronic fatigue syndrome and the “brain fog” described in long COVID. During past viral epidemics and pandemics, a commonality of neural targets may have increased viral survival by conformational matching. The neurological and psychiatric sequelae of SARS-CoV-2 infection, or long COVID, may have emerged from neural effects that have emerged from an invertebrate and vertebrate virosphere. This review aims to present a historical overview of infections and disorders associated with neurological and psychiatric sequelae that have shown similarities with long COVID.

Source: Stefano GB. Historical Insight into Infections and Disorders Associated with Neurological and Psychiatric Sequelae Similar to Long COVID. Med Sci Monit. 2021 Feb 26;27:e931447. doi: 10.12659/MSM.931447. PMID: 33633106; PMCID: PMC7924007. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7924007/ (Full text)

A systematic review of nutraceutical interventions for mitochondrial dysfunctions in myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Background: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating illness, characterised by persistent fatigue that is unrelieved by rest, in combination with a range of other disabling symptoms. There is no diagnostic test nor targeted treatment available for this illness. The pathomechanism also remains unclear. Mitochondrial dysfunctions have been considered a possible underlying pathology based on reported differences including structural and functional changes in ME/CFS patients compared to healthy controls. Due to the potential role that mitochondria may play in ME/CFS, mitochondrial-targeting nutraceutical interventions have been used to potentially assist in improving patient outcomes such as fatigue. The aim of this systematic review is to appraise literature assessing these nutraceuticals as a possible intervention for treating ME/CFS.

Methods: A systematic search of Pubmed, Embase, Medline (EBSCO host) and Web of Science (via Clarivate Analytics) for journal articles published between January 1995 and 10th November 2020 was conducted. Articles assessing nutraceutical interventions and ME/CFS patient outcomes were retrieved. Using specific inclusion and exclusion criteria, the list of articles was further refined. Quality was measured using the Rosendal scale.

Results: Nine intervention studies were included in this review. The studies investigated patient symptom severity changes such as altered fatigue levels in response to mitochondrial-targeting nutraceuticals. Improvements in fatigue levels were observed in six of the nine studies. Secondary outcomes assessed include biochemical, psychological, and quality of life parameters.

Conclusion: There is insufficient evidence on the effectiveness of mitochondria- targeting nutraceuticals in ME/CFS patients. Future well-designed studies are required to elucidate both the involvement of mitochondria in the pathomechanism of ME/CFS and the effect of mitochondrial-modifying agents on illness severity.

Source: Maksoud R, Balinas C, Holden S, Cabanas H, Staines D, Marshall-Gradisnik S. A systematic review of nutraceutical interventions for mitochondrial dysfunctions in myalgic encephalomyelitis/chronic fatigue syndrome. J Transl Med. 2021 Feb 17;19(1):81. doi: 10.1186/s12967-021-02742-4. PMID: 33596913; PMCID: PMC7890871. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-021-02742-4  (Full text)

Dysregulated Provision of Oxidisable Substrates to the Mitochondria in ME/CFS Lymphoblasts

Abstract:

Although understanding of the biomedical basis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is growing, the underlying pathological mechanisms remain uncertain. We recently reported a reduction in the proportion of basal oxygen consumption due to ATP synthesis by Complex V in ME/CFS patient-derived lymphoblast cell lines, suggesting mitochondrial respiratory inefficiency. This was accompanied by elevated respiratory capacity, elevated mammalian target of rapamycin complex 1 (mTORC1) signaling activity and elevated expression of enzymes involved in the TCA cycle, fatty acid β-oxidation and mitochondrial transport. These and other observations led us to hypothesise the dysregulation of pathways providing the mitochondria with oxidisable substrates.

In our current study, we aimed to revisit this hypothesis by applying a combination of whole-cell transcriptomics, proteomics and energy stress signaling activity measures using subsets of up to 34 ME/CFS and 31 healthy control lymphoblast cell lines from our growing library. While levels of glycolytic enzymes were unchanged in accordance with our previous observations of unaltered glycolytic rates, the whole-cell proteomes of ME/CFS lymphoblasts contained elevated levels of enzymes involved in the TCA cycle (p = 1.03 × 10-4), the pentose phosphate pathway (p = 0.034, G6PD p = 5.5 × 10-4), mitochondrial fatty acid β-oxidation (p = 9.2 × 10-3), and degradation of amino acids including glutamine/glutamate (GLS p = 0.034, GLUD1 p = 0.048, GOT2 p = 0.026), branched-chain amino acids (BCKDHA p = 0.028, BCKDHB p = 0.031) and essential amino acids (FAH p = 0.036, GCDH p = 0.006). The activity of the major cellular energy stress sensor, AMPK, was elevated but the increase did not reach statistical significance. The results suggest that ME/CFS metabolism is dysregulated such that alternatives to glycolysis are more heavily utilised than in controls to provide the mitochondria with oxidisable substrates.

Source: Missailidis D, Sanislav O, Allan CY, Smith PK, Annesley SJ, Fisher PR. Dysregulated Provision of Oxidisable Substrates to the Mitochondria in ME/CFS Lymphoblasts. Int J Mol Sci. 2021 Feb 19;22(4):2046. doi: 10.3390/ijms22042046. PMID: 33669532; PMCID: PMC7921983. https://www.mdpi.com/1422-0067/22/4/2046/htm (Full text)

Effects of Post-Exertional Malaise on Markers of Arterial Stiffness in Individuals with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Background: Evidence is emerging that individuals with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) may suffer from chronic vascular dysfunction as a result of illness-related oxidative stress and vascular inflammation. The study aimed to examine the impact of maximal-intensity aerobic exercise on vascular function 48 and 72 h into recovery.

Methods: ME/CFS (n = 11) with gender and age-matched controls (n = 11) were randomly assigned to either a 48 h or 72 h protocol. Each participant had measures of brachial blood pressure, augmentation index (AIx75, standardized to 75 bpm) and carotid-radial pulse wave velocity (crPWV) taken. This was followed by a maximal incremental cycle exercise test. Resting measures were repeated 48 or 72 h later (depending on group allocation).

Results: No significant differences were found when ME/CFS were directly compared to controls at baseline. During recovery, the 48 h control group experienced a significant 7.2% reduction in AIx75 from baseline measures (p < 0.05), while the matched ME/CFS experienced no change in AIx75. The 72 h ME/CFS group experienced a non-significant increase of 1.4% from baseline measures. The 48 h and 72 h ME/CFS groups both experienced non-significant improvements in crPWV (0.56 ms−1 and 1.55 ms−1, respectively).

Conclusions: The findings suggest that those with ME/CFS may not experience exercise-induced vasodilation due to chronic vascular damage, which may be a contributor to the onset of post-exertional malaise (PEM).

Source: Bond J, Nielsen T, Hodges L. Effects of Post-Exertional Malaise on Markers of Arterial Stiffness in Individuals with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. International Journal of Environmental Research and Public Health. 2021; 18(5):2366. https://doi.org/10.3390/ijerph18052366 https://www.mdpi.com/1660-4601/18/5/2366/htm (Full text)

Three Cases of Severe ME/CFS in Adults

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex, only partially understood multi-system disease whose onset and severity vary widely. Symptoms include overwhelming fatigue, post-exertional malaise, sleep disruptions, gastrointestinal issues, headaches, orthostatic intolerance, cognitive impairment, etc. ME/CFS is a physiological disease with an onset often triggered by a viral or bacterial infection, and sometimes by toxins. Some patients have a mild case and are able to function nearly on a par with healthy individuals, while others are moderately ill and still others are severely, or even, very severely ill. The cohort of moderately to very severely ill is often housebound or bedbound, has lost employment or career, and has engaged in a long, and often futile, search for treatment and relief. Here, we present three case studies, one each of a moderately ill, a severely ill, and a very severely ill person, to demonstrate the complexity of the disease, the suffering of these patients, and what health care providers can do to help.

Source: Williams LR, Isaacson-Barash C. Three Cases of Severe ME/CFS in Adults. Healthcare (Basel). 2021 Feb 16;9(2):215. doi: 10.3390/healthcare9020215. PMID: 33669438; PMCID: PMC7920463. https://www.mdpi.com/2227-9032/9/2/215 (Full text)

Perceptions of European ME/CFS Experts Concerning Knowledge and Understanding of ME/CFS among Primary Care Physicians in Europe: A Report from the European ME/CFS Research Network (EUROMENE)

Abstract:

Background and Objectives: We have conducted a survey of academic and clinical experts who are participants in the European ME/CFS Research Network (EUROMENE) to elicit perceptions of general practitioner (GP) knowledge and understanding of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and suggestions as to how this could be improved.

Materials and Methods: A questionnaire was sent to all national representatives and members of the EUROMENE Core Group and Management Committee. Survey responses were collated and then summarized based on the numbers and percentages of respondents selecting each response option, while weighted average responses were calculated for questions with numerical value response options. Free text responses were analysed using thematic analysis.

Results: Overall there were 23 responses to the survey from participants across 19 different European countries, with a 95% country-level response rate. Serious concerns were expressed about GPs’ knowledge and understanding of ME/CFS, and, it was felt, about 60% of patients with ME/CFS went undiagnosed as a result. The vast majority of GPs were perceived to lack confidence in either diagnosing or managing the condition. Disbelief, and misleading illness attributions, were perceived to be widespread, and the unavailability of specialist centres to which GPs could refer patients and seek advice and support was frequently commented upon. There was widespread support for more training on ME/CFS at both undergraduate and postgraduate levels.

Conclusion: The results of this survey are consistent with the existing scientific literature. ME/CFS experts report that lack of knowledge and understanding of ME/CFS among GPs is a major cause of missed and delayed diagnoses, which renders problematic attempts to determine the incidence and prevalence of the disease, and to measure its economic impact. It also contributes to the burden of disease through mismanagement in its early stages.

Source: Cullinan J, Pheby DFH, Araja D, Berkis U, Brenna E, de Korwin JD, Gitto L, Hughes DA, Hunter RM, Trepel D, Wang-Steverding X. Perceptions of European ME/CFS Experts Concerning Knowledge and Understanding of ME/CFS among Primary Care Physicians in Europe: A Report from the European ME/CFS Research Network (EUROMENE). Medicina (Kaunas). 2021 Feb 26;57(3):208. doi: 10.3390/medicina57030208. PMID: 33652747. https://www.mdpi.com/1010-660X/57/3/208 (Full text)

Effect of acupoint catgut embedding in chronic fatigue syndrome patients: A protocol for systematic review and meta-analysis

Abstract:

Background: Chronic fatigue syndrome (CFS) is a relatively complex and disabling illness with a substantial economic burden and functional impairment. Until now, many CFS patients lack appropriate healthcare. Acupoint catgut embedding is an effective and emerging alternative therapy for CFE. With this research, we endeavor to investigate the effect and safety of ACE for CFS.

Methods: Eight databases will be searched from inception to December 2020: PubMed, EMBASE, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chong-Qing VIP database, and Wan-fang database. We regard studies as eligible for inclusion if they were RCTs done in CFS patients, compare acupoint catgut embedding to another treatment strategy, and report fatigue changes at the end of the intervention period. Two independent reviewers complete the study selection, data extraction, and the risk of bias assessment. We assess pooled data using a random-effects model through Revman software (v.5.3) and Stata (version 15.0).

Ethics and dissemination: Ethics approval is not required because the individual patient data will not be involved, with no privacy concerns. This systematic review and meta-analysis will provide a reference for CFS patients and clinicians on the non-drug interventions. We will publish and disseminate the results of this review in a peer-reviewed journal or relevant conference.

Source: Zhang ML, Fu HJ, Tang Y, Luo ZG, Li JY, Li R. Effect of acupoint catgut embedding in chronic fatigue syndrome patients: A protocol for systematic review and meta-analysis. Medicine (Baltimore). 2021 Feb 5;100(5):e23946. doi: 10.1097/MD.0000000000023946. PMID: 33592847; PMCID: PMC7870242. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7870242/ (Full text)

Who should we ask about mental health symptoms in adolescents with CFS/ME? Parent-child agreement on the revised children’s anxiety and depression scale

Abstract:

Background: One in three adolescents with chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) have mental health problems. Multi-informant perspectives are key to psychological assessment. Understanding parent-child agreement is crucial to accurate diagnosis, particularly where severe fatigue limits self-report.

Methods: Agreement on the revised children’s anxiety and depression scale (RCADs) was assessed between parents and children with CFS/ME (n = 93) using Bland-Altman plots, cross tabulations and regression analyses.

Results: Diagnostic thresholds were met more frequently based on child-report. Parent- and child-report had similar sensitivity and specificity on RCADS compared to gold-standard diagnostic interviews. Regression analysis found similar accuracy between both reports. For anxiety diagnoses, odds ratio (OR) for child-report was 1.10 (CI = 1.06-1.14), and 1.10 (CI = 1.05-1.14) for parent-report. For depression, OR for child report was 1.26 (CI = 1.11-1.43), while for parent-report is was 1.25 (CI = 1.10-1.41). For total score, OR for child-report was 1.10 (CI = 1.05-1.13) while OR for parent-report was 1.09 (CI = 1.05-1.13).

Conclusions: Reasonable agreement was observed between parent- and child-report of mental health symptoms in paediatric CFS/ME. While parent-report can facilitate psychological evaluation in CFS/ME, this is not a substitute for a child’s own report.

Source: Serafimova T, Loades M, Gaunt D, Crawley E. Who should we ask about mental health symptoms in adolescents with CFS/ME? Parent-child agreement on the revised children’s anxiety and depression scale. Clin Child Psychol Psychiatry. 2021 Feb 15:1359104521994880. doi: 10.1177/1359104521994880. Epub ahead of print. PMID: 33586480.  https://pubmed.ncbi.nlm.nih.gov/33586480/

Association between chronic fatigue syndrome and suicidality among survivors of Middle East respiratory syndrome over a 2-year follow-up period

Abstract:

Suicide is an important public health issue during the current pandemic of emerging infectious diseases (EIDs). In EIDs, various symptoms persist even after recovery, and chronic fatigue is among those that are commonly reported. The aim of this study was to examine the effects of chronic fatigue syndrome on suicidality during the recovery phase among survivors of Middle East respiratory syndrome (MERS). MERS survivors were recruited from five centers and prospectively followed up for 2 years. In total, 63 participants were registered at 12 months (T1), of whom 53 and 50 completed the assessments at 18 months (T2) and 24 months (T3), respectively. Suicidality and chronic fatigue were evaluated using the suicidality module of the Mini-International Neuropsychiatric Interview (MINI) and the Fatigue Severity Scale (FSS), respectively.

We analyzed the relationship between chronic fatigue and suicidality during the follow-up period using the generalized estimating equation (GEE). The suicidality rates were 22.2% (n = 14), 15.1% (n = 8), and 10.0% (n = 5) at T1-T3, respectively. Of the 63 participants, 29 had chronic fatigue syndrome at T1. The group that reported chronic fatigue syndrome at T1 was more likely to experience suicidality during the 2-year follow-up than the group that reported otherwise (RR: 7.5, 95% CI: 2.4-23.1). This association was present even after adjusting for potential confounders (RR: 7.6, 95% CI: 2.2-26.0). Chronic fatigue syndrome and suicide risk among emerging infectious disease (EID) survivors should be acknowledged, and effective interventions must be developed.

Source: Ahn SH, Kim JL, Kim JR, Lee SH, Yim HW, Jeong H, Chae JH, Park HY, Lee JJ, Lee H. Association between chronic fatigue syndrome and suicidality among survivors of Middle East respiratory syndrome over a 2-year follow-up period. J Psychiatr Res. 2021 Feb 17;137:1-6. doi: 10.1016/j.jpsychires.2021.02.029. Epub ahead of print. PMID: 33631632; PMCID: PMC7888998. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7888998/  (Full text)

Recursive ensemble feature selection provides a robust mRNA expression signature for myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disorder characterized by disabling fatigue. Several studies have sought to identify diagnostic biomarkers, with varying results. Here, we innovate this process by combining both mRNA expression and DNA methylation data. We performed recursive ensemble feature selection (REFS) on publicly available mRNA expression data in peripheral blood mononuclear cells (PBMCs) of 93 ME/CFS patients and 25 healthy controls, and found a signature of 23 genes capable of distinguishing cases and controls.

REFS highly outperformed other methods, with an AUC of 0.92. We validated the results on a different platform (AUC of 0.95) and in DNA methylation data obtained from four public studies on ME/CFS (99 patients and 50 controls), identifying 48 gene-associated CpGs that predicted disease status as well (AUC of 0.97). Finally, ten of the 23 genes could be interpreted in the context of the derailed immune system of ME/CFS.

Source: Metselaar, P.I., Mendoza-Maldonado, L., Li Yim, A.Y.F. et al. Recursive ensemble feature selection provides a robust mRNA expression signature for myalgic encephalomyelitis/chronic fatigue syndrome. Sci Rep 11, 4541 (2021). https://doi.org/10.1038/s41598-021-83660-9 https://www.nature.com/articles/s41598-021-83660-9 (Full text)