Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and fibromyalgia are indistinguishable by their cerebrospinal fluid proteomes

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and fibromyalgia have overlapping neurologic symptoms particularly disabling fatigue. This has given rise to the question whether they are distinct central nervous system (CNS) entities or is one an extension of the other. To investigate this, we used unbiased quantitative mass spectrometry-based proteomics to examine the most proximal fluid to the brain, cerebrospinal fluid (CSF). This was to ascertain if the proteome profile of one was the same or different from the other.

We examined two separate groups of ME/CFS, one with (n=15) and one without (n=15) fibromyalgia. We quantified a total of 2,083 proteins using immunoaffinity depletion, tandem mass tag isobaric labeling and offline two-dimensional liquid chromatography coupled to tandem mass spectrometry, including 1,789 that were quantified in all the CSF samples. ANOVA analysis did not yield any proteins with an adjusted p-value < 0.05. This supports the notion that ME/CFS and fibromyalgia as currently defined are not distinct entities.

Source: Steven E. SchutzerTao LiuChia-Feng TsaiVladislav A. PetyukAthena A. SchepmoesYi-Ting WangKarl K. WeitzJonas BergquistRichard D. SmithBenjamin H Natelson. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and fibromyalgia are indistinguishable by their cerebrospinal fluid proteomes.

Genetic and epigenetic regulation of Catechol-O-methyltransferase in relation to inflammation in chronic fatigue syndrome and Fibromyalgia

Abstract:

Background: Catechol-O-methyltransferase (COMT) has been shown to influence clinical pain, descending modulation, and exercise-induced symptom worsening. COMT regulates nociceptive processing and inflammation, key pathophysiological features of Chronic Fatigue Syndrome and Fibromyalgia (CFS/FM). We aimed to determine the interactions between genetic and epigenetic mechanisms regulating COMT and its influence on inflammatory markers and symptoms in patients with CFS/FM.

Methods: A case-control study with repeated-measures design was used to reduce the chance of false positive and increase the power of our findings. Fifty-four participants (28 patients with CFS/FM and 26 controls) were assessed twice within 4 days. The assessment included clinical questionnaires, neurophysiological assessment (pain thresholds, temporal summation, and conditioned pain modulation), and blood withdrawal in order to assess rs4818, rs4633, and rs4680 COMT polymorphisms and perform haplotype estimation, DNA methylation in the COMT gene (both MB-COMT and S-COMT promoters), and cytokine expression (TNF-α, IFN-γ, IL-6, and TGF-β).

Results: COMT haplotypes were associated with DNA methylation in the S-COMT promoter, TGF-β expression, and symptoms. However, this was not specific for one condition. Significant between-group differences were found for increased DNA methylation in the MB-COMT promoter and decreased IFN-γ expression in patients.

Discussion: Our results are consistent with basic and clinical research, providing interesting insights into genetic-epigenetic regulatory mechanisms. MB-COMT DNA methylation might be an independent factor contributing to the pathophysiology of CFS/FM. Further research on DNA methylation in complex conditions such as CFS/FM is warranted. We recommend future research to employ a repeated-measure design to control for biomarkers variability and within-subject changes.

Source: Polli A, Hendrix J, Ickmans K, Bakusic J, Ghosh M, Monteyne D, Velkeniers B, Bekaert B, Nijs J, Godderis L. Genetic and epigenetic regulation of Catechol-O-methyltransferase in relation to inflammation in chronic fatigue syndrome and Fibromyalgia. J Transl Med. 2022 Oct 25;20(1):487. doi: 10.1186/s12967-022-03662-7. PMID: 36284330; PMCID: PMC9598022. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9598022/ (Full text)

Genetic risk factors for ME/CFS identified using combinatorial analysis

Abstract:

Background:Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating chronic disease that lacks known pathogenesis, distinctive diagnostic criteria, and effective treatment options. Understanding the genetic (and other) risk factors associated with the disease would begin to help to alleviate some of these issues for patients.

Methods: We applied both GWAS and the PrecisionLife combinatorial analytics platform to analyze ME/CFS cohorts from UK Biobank, including the Pain Questionnaire cohort, in a case-control design with 1,000 cycles of fully random permutation. Results from this study were supported by a series of replication and cohort comparison experiments, including use of disjoint Verbal Interview CFS, post-viral fatigue syndrome and fibromyalgia cohorts also derived from UK Biobank, and results compared for overlap and reproducibility.

Results: Combinatorial analysis revealed 199 SNPs mapping to 14 genes, that were significantly associated with 91% of the cases in the ME/CFS population. These SNPs were found to stratify by shared cases into 15 clusters (communities) made up of 84 high-order combinations of between 3-5 SNPs. p-values for these communities range from 2.3 × 10−10 to 1.6 × 10−72. Many of the genes identified are linked to the key cellular mechanisms hypothesized to underpin ME/CFS, including vulnerabilities to stress and/or infection, mitochondrial dysfunction, sleep disturbance and autoimmune development. We identified 3 of the critical SNPs replicated in the post-viral fatigue syndrome cohort and 2 SNPs replicated in the fibromyalgia cohort. We also noted similarities with genes associated with multiple sclerosis and long COVID, which share some symptoms and potentially a viral infection trigger with ME/CFS.

Conclusions: This study provides the first detailed genetic insights into the pathophysiological mechanisms underpinning ME/CFS and offers new approaches for better diagnosis and treatment of patients

Source: Sayoni Das, Krystyna Taylor, James Kozubek, Jason Sardell, Steve Gardner. Genetic Risk Factors for ME/CFS Identified using Combinatorial Analysis. medRxiv 2022.09.09.22279773; doi: https://doi.org/10.1101/2022.09.09.22279773  https://www.medrxiv.org/content/10.1101/2022.09.09.22279773v2.full-text (Full text)

Cognitive task performance and subjective cognitive symptoms in individuals with Chronic Fatigue Syndrome or Fibromyalgia: A cross-sectional analysis of the Lifelines cohort study

Abstract:

Objective: This study examined cognitive task performance and self-reported cognitive functioning in individuals with chronic fatigue syndrome (CFS) and fibromyalgia (FM) in a population-based sample and investigated the role of mood and anxiety disorders as well as severity of the physical symptoms.

Methods: This study was performed in 79,966 participants (Mean age: 52.9, SD = ±12.6 years, 59.2% women) from the Lifelines general-population. Symptoms consistent with the diagnostic criteria for CFS and FM were assessed using questionnaires. Two comparison groups were used: participants with self-reported medical disorders with well-defined pathophysiology (i.e., multiple sclerosis and rheumatic arthritis) and controls without these diseases. Objective task-performance was based on the computerized CogState cognitive battery and subjective cognitive symptoms using the concentration subscale of the Checklist Individual Strength.

Results: Cognitive task performance was poorer in individuals with CFS vs. controls without disease and controls with a medical disorder, although the severity of cognitive dysfunction was mild. Participants meeting criteria for CFS (n = 2,461) or FM (n = 4,295) reported more subjective cognitive symptoms compared to controls without a medical disorder (d = 1.53, 95%CI = 1.49-1.57 for CFS; d = 1.25, 95%CI = 1.22-1.29 for FM) and participants with a medical disease (d = 0.62, 95%CI = 0.46-0.79 for CFS; d = 0.75, 95%CI = 0.70-0.80 for FM). These differences remained essentially the same when excluding participants with comorbid mood or anxiety disorders or adjusting for physical symptom severity.

Conclusions: Subjective cognitive symptoms and to a lesser extent suboptimal cognitive task performance are more prevalent in individuals with CFS or FM compared to controls without these conditions.

Source: Joustra ML, Hartman CA, Bakker SJL, Rosmalen JGM. Cognitive task performance and subjective cognitive symptoms in individuals with Chronic Fatigue Syndrome or Fibromyalgia: A cross-sectional analysis of the Lifelines cohort study. Psychosom Med. 2022 Aug 2. doi: 10.1097/PSY.0000000000001117. Epub ahead of print. PMID: 35980775.  https://pubmed.ncbi.nlm.nih.gov/35980775/

Prevalence of fibromyalgia 10 years after infection with Giardia lamblia: a controlled prospective cohort study

Abstract:

Objectives: To investigate whether acute infection with Giardia lamblia is associated with fibromyalgia 10 years after infection and whether fibromyalgia is associated with irritable bowel syndrome (IBS) and chronic fatigue (CF) in this setting.

Methods: A cohort study was established after an outbreak of G. lamblia in Bergen, Norway, 2004. Laboratory-confirmed cases and a matched control group were followed for 10 years. The main outcome was fibromyalgia 10 years after giardiasis, defined by the 2016 revisions of the fibromyalgia diagnostic criteria using the Fibromyalgia Survey Questionnaire (FSQ).

Results: The prevalence of fibromyalgia was 8.6% (49/572) among Giardia exposed compared to 3.1% (21/673) in controls (p<0.001). Unadjusted odds for having fibromyalgia was higher for Giardia exposed compared to controls (odds ratio (OR): 2.91, 95% confidence interval (CI): 1.72, 4.91), but adjusted for IBS and CF it was not (OR: 1.05, 95% CI: 0.57, 1.95). Among participants without CF the odds for fibromyalgia was 6.27 times higher for participants with IBS than those without (95% CI: 3.31, 11.91) regardless of exposure. Among participants without IBS the odds for fibromyalgia was 4.80 times higher for those with CF than those without (95% CI: 2.75, 8.37).

Conclusions: We found a higher prevalence of fibromyalgia among Giardia exposed compared to controls 10 years after the acute infection. Fibromyalgia was strongly associated with IBS and CF, and the difference between the exposed and controls can be attributed to the high prevalence of IBS and CF among the Giardia exposed. Notably, this study was not designed to establish causality between Giardia exposure and the outcomes.

Source: Hunskar GS, Rortveit G, Litleskare S, Eide GE, Hanevik K, Langeland N, Wensaas KA. Prevalence of fibromyalgia 10 years after infection with Giardia lamblia: a controlled prospective cohort study. Scand J Pain. 2021 Oct 21;22(2):348-355. doi: 10.1515/sjpain-2021-0122. PMID: 34679267. https://www.degruyter.com/document/doi/10.1515/sjpain-2021-0122/html (Full text)

Clinical overlap between fibromyalgia and myalgic encephalomyelitis. A systematic review and meta-analysis

Abstract:

Myalgic encephalomyelitis is an illness characterized by profound malaise after mental or physical effort occurring in patients already suffering from constant fatigue. On the other hand, widespread pain and widespread allodynia are the core fibromyalgia clinical features. There is controversy on these two syndromes alikeness. Through the years, different diagnostic and/or classification criteria have been put forward to appraise both fibromyalgia and myalgic encephalomyelitis. The epidemiology of these two illnesses, and their overlap, may vary accordingly to the used definition. The most recent Wolfe et al. 2016 fibromyalgia diagnostic criteria incorporates three myalgic encephalomyelitis features including fatigue, waking unrefreshed and dyscognition. The objective of this meta-analysis was to define the clinical overlap between fibromyalgia and myalgic encephalomyelitis based on a systematic literature review.

Methods: PubMed, Embase, Lilacs, and Cochrane data bases were searched on January 25, 2021 linking the medical subject heading “Fibromyalgia” to the following terms “chronic fatigue syndrome”, “myalgic encephalomyelitis” and “systemic exertion intolerance disease”. Our review included all original articles in which the clinical overlap between fibromyalgia and myalgic encephalomyelitis could be quantified based on recognized diagnostic or classification criteria. Articles scrutiny and selection followed the PRISMA guidelines. Each study quality was assessed according to GRADE recommendations. The global clinical overlap was calculated using a fixed effect model with inverse variance-weighted average method.

Results: Twenty one publications were included in the meta-analysis. Reviewed studies were highly dissimilar in their design, objectives, sample size, diagnostic criteria, and/or outcomes yielding a 98% heterogeneity index. Nevertheless, the clinical overlap between fibromyalgia and myalgic encephalomyelitis was a well defined outcome that could be reliably calculated despite the high heterogeneity value. All reviewed publications had moderate GRADE evidence level. Most evaluated articles used the old 1990 Wolfe et al. fibromyalgia diagnostic criteria. Myalgic encephalomyelitis and fibromyalgia diagnoses overlapped in 47.3% (95% CI: 45.97-48.63) of the reported cases.

Conclusion: This meta-analysis found prominent clinical overlap between fibromyalgia and myalgic encephalomyelitis. It seems likely that this concordance would be even higher when using the most recent Wolfe et al. 2016 fibromyalgia diagnostic criteria.

Source: Ramírez-Morales R, Bermúdez-Benítez E, Martínez-Martínez LA, Martínez-Lavín M. Clinical overlap between fibromyalgia and myalgic encephalomyelitis. A systematic review and meta-analysis. Autoimmun Rev. 2022 Jun 8:103129. doi: 10.1016/j.autrev.2022.103129. Epub ahead of print. PMID: 35690247. https://pubmed.ncbi.nlm.nih.gov/35690247/

Mechanistic factors contributing to pain and fatigue in fibromyalgia and ME/CFS: autonomic and inflammatory insights from an experimental medicine study

Abstract:

Background: Fibromyalgia and ME/CFS are multifaceted conditions with overlapping symptoms(1); the pathoaetiological mechanisms are complex and debated(2), however there is a strong association with features of hereditary disorders of connective tissue (hypermobility) and autonomic and inflammatory abnormalities (1,2).

Objectives: To determine potential autonomic and inflammatory mechanisms of pain and fatigue in fibromyalgia and ME/CFS

Methods: After excluding participants with WCC higher than 10 (suggesting acute infection) baseline markers of inflammation (CRP and ESR) were available for 60 patients with confirmed diagnoses of Fibromyalgia and/ or ME/CFS and 23 matched controls. Participants then underwent full research diagnostic evaluation including a hypermobility assessment(1) and autonomic challenge (60 degree head up tilt, ISRCTN78820481). Subjective pain and fatigue were assessed before and after challenge (VAS). Linear regression models were used to explore predictors, with adjustment for confounders as appropriate. Mediation analyses (looking for mechanistic effects) were conducted according to the method of Hayes (3) and mediation considered significant if bootstrapped confidence intervals of the estimated indirect effect did not cross zero. In these mediation analyses predictor variable was group membership (patient or control), outcome variable was change in 1)pain and 2)fatigue induced by challenge and mediatiors 1)no of connective tissue features in hypermobility diagnostic criteria endorsed by participant; 2)baseline inflammatory markers.

Results: ESR and CRP were significantly higher in patients rather than controls, even after correcting for BMI, age and sex (B=5.15, t=2.05, p=0.044; B=1.77, t=2.15, p=0.044 respectively). Adjusted ESR and CRP correlated with both subjective fatigue (B=0.44, t=2.09, p=0.04; B=1.63, t=2.60, p=0.011) and pain severity (B=0.13, t=2.51, p=0.014; B=0.45, t=3.01, p=0.004) at baseline. Autonomic challenge amplified pain (B=14.20, t=2.87, p=0.005) and fatigue (B=31.48, t=5.95, p=<0.001) in patients to a significantly greater degree than controls, controlling for baseline levels. Baseline ESR and CRP also predicted challenge-induced increase in fatigue (B=0.78, t=370, p=<0.001; B=1.91, t=3.36, p=<0.001) and ESR challenge-induced increases in pain (B=0.46, t=2.35, p=0.021).

Mediation analysis demonstrated that number of connective tissue features expressed in hypermobility criteria mediated the degree to which subjective pain was increased by the autonomic challenge (Bootstraped 95% CI of indirect effect do not cross zero, 0.1572 – 6.8171). ESR mediated the degree to which subjective fatigue was increased by the autonomic challenge (Bootstraped 95% CI of indirect effect do not cross zero,0.7541 – 7.3888).

Conclusion: To our knowledge this is the first study to directly explore autonomic and inflammatory mechanisms of pain and fatigue in a combined population of Fibromyalgia and ME/CFS. This study this adds to the evidence-base of baseline inflammatory abnormalities in fibromyalgia and ME/CFS. It highlights their potential role in predicting symptom severity and their potential mechanistic role in autonomic induced pain and fatigue, suggesting future treatment strategies.

Source: Eccles JThompson CThompson B, et al. AB1209 MECHANISTIC FACTORS CONTRIBUTING TO PAIN AND FATIGUE IN FIBROMYALGIA AND ME/CFS: AUTONOMIC AND INFLAMMATORY INSIGHTS FROM AN EXPERIMENTAL MEDICINE STUDY.

The impact of Micro RNA-320a serum level on severity of symptoms and cerebral processing of pain in patients with fibromyalgia

Abstract:

Objectives: The aim of this work was to explore the expression of miR-320a level in fibromyalgia patients in comparison to healthy controls, and to clarify its impact on the severity of symptoms and the cerebral processing of pain assessed by middle latency somatosensory evoked potentials (SSEPs).

Design: Case-control study.

Setting: Rheumatology and Neurology outpatient clinics.

Subjects: Seventy-four fibromyalgia patients and seventy-four normal healthy controls.

Methods: The included patients were subjected to detailed history taking, assessment of severity of fibromyalgia symptoms using the Fibromyalgia Impact Questionnaire Revised (FIQR), assessment of pain intensity using the Neuropathic Pain Symptom Inventory (NPSI), measurement of the serum level of miR-320a in addition to of measurement peak latencies and amplitudes of middle latency SSEPs.

Results: Fibromyalgia patients had significantly higher micro-RNA-320a levels (0.907 ± 0.022) in comparison to controls (0.874 ± 0.015) (P-value < 0.001). The mean values of micro-RNA-320a levels were significantly higher in fibromyalgia patients with insomnia, chronic fatigue syndrome, persistent depressive disorder, and primary headache disorder than those without (P-value = 0.024, <0.001, 0.006, 0.036 respectively). There were statistically significant positive correlations between micro-RNA-320a levels, and disease duration, FIQR and NPSI total scores (P-value <0.001, 0.003, 0.002 respectively). There were no statistically significant correlations between micro-RNA-320a levels and middle latency SSEPs.

Discussion: Micro-RNA-320a level is significantly upregulated in fibromyalgia patient. It has a crucial impact on the severity of symptoms but not related to the cerebral processing of pain.

Source: Hussein M, Fathy W, Abdelaleem EA, Nasser M, Yehia A, Elanwar R. The impact of Micro RNA-320a serum level on severity of symptoms and cerebral processing of pain in patients with fibromyalgia. Pain Med. 2022 May 19:pnac076. doi: 10.1093/pm/pnac076. Epub ahead of print. PMID: 35587745. https://pubmed.ncbi.nlm.nih.gov/35587745/

A distinctive profile of family genetic risk scores in a Swedish national sample of cases of fibromyalgia, irritable bowel syndrome, and chronic fatigue syndrome compared to rheumatoid arthritis and major depression

Abstract:

Background: Functional somatic disorders (FSD) feature medical symptoms of unclear etiology. Attempts to clarify their origin have been hampered by a lack of rigorous research designs. We sought to clarify the etiology of the FSD by examining the genetic risk patterns for FSD and other related disorders.

Methods: This study was performed in 5 829 186 individuals from Swedish national registers. We quantified familial genetic risk for FSD, internalizing disorders, and somatic disorders in cases of chronic fatigue syndrome (CFS), fibromyalgia (FM), and irritable bowel syndrome (IBS), using a novel method based on aggregate risk in first to fifth degree relatives, adjusting for cohabitation. We compared these profiles with those of a prototypic internalizing psychiatric – major depression (MD) – and a somatic/autoimmune disorder: rheumatoid arthritis (RA).

Results: Patients with FM carry substantial genetic risks not only for FM, but also for pain syndromes and internalizing, autoimmune and sleep disorders. The genetic risk profiles for IBS and CFS are also widely distributed although with lower average risks. By contrast, genetic risk profiles of MD and RA are much more restricted to related conditions.

Conclusion: Patients with FM have a relatively unique family genetic risk score profile with elevated genetic risk across a range of disorders that differs markedly from the profiles of a classic autoimmune disorder (RA) and internalizing disorder (MD). A similar less marked pattern of genetic risks was seen for IBS and CFS. FSD arise from a distinctive pattern of genetic liability for a diversity of psychiatric, autoimmune, pain, sleep, and functional somatic disorders.

Source: Kendler KS, Rosmalen JGM, Ohlsson H, Sundquist J, Sundquist K. A distinctive profile of family genetic risk scores in a Swedish national sample of cases of fibromyalgia, irritable bowel syndrome, and chronic fatigue syndrome compared to rheumatoid arthritis and major depression. Psychol Med. 2022 Mar 31:1-8. doi: 10.1017/S0033291722000526. Epub ahead of print. PMID: 35354508.

Central sensitisation in chronic fatigue syndrome and fibromyalgia; a case control study

Abstract:

Introduction: Chronic fatigue syndrome (CFS) and fibromyalgia (FM) are both complex conditions that are challenging to treat. This may be related to an incomplete understanding of their pathophysiology, itself obfuscated by their heterogeneity. The symptomatic overlap between them and their common comorbidity suggests a shared vulnerability, which might be explained by central sensitisation.

Methods: 19 CFS cases, 19 FM cases and 20 age and sex matched healthy controls (HC) were recruited primarily from secondary care clinics in London. Those with other pain disorders, psychiatric diagnoses and those taking centrally acting or opiate medications were excluded. Participants were asked to abstain from alcohol and over the counter analgaesia 48 h prior to assessment by static and dynamic quantitative sensory tests, including measures of temporal summation (TS) and conditioned pain modulation (CPM).

Results: CS, as defined by the presence of both enhanced TS and inefficient CPM, was present in 16 (84%) CFS cases, 18 (95%) FM cases, and none of the HC (p < 0.001). Pressure pain thresholds were lower in CFS (Median222kPaIQR 146-311; p = 0.04) and FM cases (Median 189 kPa; IQR 129-272; p = 0.003) compared to HC (Median 311 kPa; IQR 245-377). FM cases differed from HC in cold-induced (FM = 22.6 °C (15.3-27.7) vs HC = 14.2 °C (9.0-20.5); p = 0.01) and heat-induced (FM = 38.0 °C (35.2-44.0) vs HC = 45.3 °C (40.1-46.8); p = 0.03) pain thresholds, where CFS cases did not.

Conclusion: Central sensitisation may be a common endophenotype in chronic fatigue syndrome and fibromyalgia. Further research should address whether central sensitisation is a cause or effect of these disorders.

Source: Bourke JH, Wodehouse T, Clark LV, Constantinou E, Kidd BL, Langford R, Mehta V, White PD. Central sensitisation in chronic fatigue syndrome and fibromyalgia; a case control study. J Psychosom Res. 2021 Sep 21;150:110624. doi: 10.1016/j.jpsychores.2021.110624. Epub ahead of print. PMID: 34600309. https://pubmed.ncbi.nlm.nih.gov/34600309/