Verification of exercise-induced transient postural tachycardia phenotype in Gulf War Illness

Abstract:

One third of Gulf War Illness (GWI) subjects in a recent study were found to develop transient postural tachycardia after submaximal exercise stress tests. Post-exercise postural tachycardia is a previously undescribed physiological finding. A new GWI cohort was studied to verify this novel finding and characterize this cardiovascular phenomenon. Subjects followed the same protocol as before. The change in heart rate between recumbent and standing postures (ΔHR) was measured before exercise, and after submaximal bicycle exercise. About one-fourth of the verification cohort (14/57) developed transient postural tachycardia after submaximal exercise. These subjects were the Stress Test Activated Reversible Tachycardia (START) phenotype. The largest change was observed between pre-exercise and time points 2 ± 1 (mean ± SD) hours post exercise (1st Peak Effect). Eleven subjects had Postural Tachycardia Syndrome (POTS) before and after exercise. The remaining subjects had normal ΔHR (12 ± 5 bpm) and no 1st Peak Effect, and were the Stress Test Originated Phantom Perception phenotype (STOPP). These findings indicate that about one-fourth of all Gulf War Illness study participants (24/90) developed transient postural tachycardia after the submaximal exercise stress test. The START phenotype was defined as being distinctly different from POTS. Additional studies are required to examine this phenomenon in other illnesses and to determine pathological mechanisms.

Source: Garner RS, Rayhan RU, Baraniuk JN. Verification of exercise-induced transient postural tachycardia phenotype in Gulf War Illness. Am J Transl Res. 2018 Oct 15;10(10):3254-3264. eCollection 2018. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6220213/ (Full article)

Can a Chronic BPPV With a History of Trauma be the Trigger of Symptoms in Vestibular Migraine, Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), and Whiplash Associated Disorders (WAD)? A Retrospective Cohort Study

Abstract:

BACKGROUND: In patients with chronic benign paroxysmal positional vertigo (BPPV), i.e., chronic vestibular multicanalicular canalithiasis (CVMCC), abnormal signals are transmitted from diseased labyrinths via the healthy vestibular nuclei complex to their end organs. The vestibulo-thalamo-cortical reflex as proposed in vestibular migraine is just one of these reflexes. In a group of patients diagnosed with CVMCC otolith repositioning maneuvers specific for each semicircular canal (SCC) ameliorated pain and other symptoms in 90%. Increased awareness of CVMCC may reduce suffering and continuous medication.

OBJECTIVE: To evaluate if CVMCC can be the trigger of symptoms in vestibular migraine, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), and whiplash associated disorders (WAD).

STUDY DESIGN: Retrospective consecutive observational cohort study.

SETTING: Ambulatory at a private Otoneurology Centre.

PATIENTS: One hundred sixty-three patients with CVMCC and a history of trauma.

INTERVENTION: Based on the symptoms (structured symptom questionnaire), the patients are post hoc sub grouped according to the criteria of the different diagnoses.

MAIN OUTCOME MEASURE: Frequency of patients with CVMCC who fulfill the criteria of the different diagnoses.

RESULTS: 98% of all patients with CVMCC fulfill the Barany Society criteria of a probable vestibular migraine; 17% fulfill the International Classification of Headache Disorders defined vestibular migraine criteria; 63% fulfill the Fukuda criteria of ME/CFS; 100% of the patients with WAD suffer from CVMCC.

CONCLUSION: This survey supports the hypothesis that CVMCC can be the trigger of symptoms in vestibular migraine, ME/CFS, and WAD. The actual diagnosis the patient receives is often in accordance with the patient’s dominant symptom.

Source: Tjell C, Iglebekk W, Borenstein P. Can a Chronic BPPV With a History of Trauma be the Trigger of Symptoms in Vestibular Migraine, Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), and Whiplash Associated Disorders (WAD)? A Retrospective Cohort Study. Otol Neurotol. 2018 Oct 9. doi: 10.1097/MAO.0000000000002020. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/30303941

Chronic Fatigue Syndrome: From Chronic Fatigue to More Specific Syndromes

Abstract:

In the last decade, a group of chronic disorders associated with fatigue (CDAF) emerged as the leading cause of chronic fatigue, chronic pain, and functional impairment, all of which have been often labeled in clinical practice as chronic fatigue syndrome (CFS) or fibromyalgia. While these chronic disorders arise from various pathophysiologic mechanisms, a shared autoimmune or immune-mediated etiology could shift the focus from symptomatic treatment of fatigue and pain to targeted immunomodulatory and biological therapy.

A clinical paradigm shift is necessary to reevaluate CFS and fibromyalgia diagnoses and its relationship to the CDAF entities, which would ultimately lead to a change in diagnostic and therapeutic algorithm for patients with chronic fatigue and chronic pain. Rather than uniformly apply the diagnoses of CFS or fibromyalgia to any patient presenting with unexplained chronic fatigue or chronic pain, it may be more beneficial and therapeutically effective to stratify these patients into more specific diagnoses in the CDAF group.

Source: Blitshteyn S, Chopra P. Chronic Fatigue Syndrome: From Chronic Fatigue to More Specific Syndromes. Eur Neurol. 2018 Oct 4;80(1-2):73-77. doi: 10.1159/000493531. [Epub ahead of print]  https://www.ncbi.nlm.nih.gov/pubmed/30286454

Successful treatment of postural orthostatic tachycardia and mast cell activation syndromes using naltrexone, immunoglobulin and antibiotic treatment

Abstract:

A patient with severe postural orthostatic tachycardia syndrome (POTS) and mast cell activation syndrome (MCAS) received immunotherapy with low-dose naltrexone (LDN) and intravenous immunoglobulin (IVIg) and antibiotic therapy for small intestinal bacterial overgrowth (SIBO). A dramatic and sustained response was documented. The utility of IVIg in autoimmune neuromuscular diseases has been published, but clinical experience with POTS is relatively unknown and has not been reported in MCAS. As a short-acting mu-opioid antagonist, LDN paradoxically increases endorphins which then bind to regulatory T cells which regulate T-lymphocyte and B-lymphocyte production and this reduces cytokine and antibody production. IVIg is emerging as a promising therapy for POTS. Diagnosis and treatment of SIBO in POTS is a new concept and appears to play an important role.

Source: Leonard B Weinstock, Jill B Brook, Trisha L Myers, Brent Goodman. Successful treatment of postural orthostatic tachycardia and mast cell activation syndromes using naltrexone, immunoglobulin and antibiotic treatment. Case Report. BMJ Case Rep. 2018; 2018: bcr2017221405. Published online 2018 Jan 11. doi: 10.1136/bcr-2017-221405 PMCID: PMC5778345 PMID: 29326369. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5778345/ (Full article)

High-fidelity discrete modeling of the HPA axis: a study of regulatory plasticity in biology

Abstract:

BACKGROUND: The hypothalamic-pituitary-adrenal (HPA) axis is a central regulator of stress response and its dysfunction has been associated with a broad range of complex illnesses including Gulf War Illness (GWI) and Chronic Fatigue Syndrome (CFS). Though classical mathematical approaches have been used to model HPA function in isolation, its broad regulatory interactions with immune and central nervous function are such that the biological fidelity of simulations is undermined by the limited availability of reliable parameter estimates.

METHOD: Here we introduce and apply a generalized discrete formalism to recover multiple stable regulatory programs of the HPA axis using little more than connectivity between physiological components. This simple discrete model captures cyclic attractors such as the circadian rhythm by applying generic constraints to a minimal parameter set; this is distinct from Ordinary Differential Equation (ODE) models, which require broad and precise parameter sets. Parameter tuning is accomplished by decomposition of the overall regulatory network into isolated sub-networks that support cyclic attractors. Network behavior is simulated using a novel asynchronous updating scheme that enforces priority with memory within and between physiological compartments.

RESULTS: Consistent with much more complex conventional models of the HPA axis, this parsimonious framework supports two cyclic attractors, governed by higher and lower levels of cortisol respectively. Importantly, results suggest that stress may remodel the stability landscape of this system, favoring migration from one stable circadian cycle to the other. Access to each regime is dependent on HPA axis tone, captured here by the tunable parameters of the multi-valued logic. Likewise, an idealized glucocorticoid receptor blocker alters the regulatory topology such that maintenance of persistently low cortisol levels is rendered unstable, favoring a return to normal circadian oscillation in both cortisol and glucocorticoid receptor expression.

CONCLUSION: These results emphasize the significance of regulatory connectivity alone and how regulatory plasticity may be explored using simple discrete logic and minimal data compared to conventional methods.

Source: Sedghamiz H, Morris M, Craddock TJA, Whitley D, Broderick G. High-fidelity discrete modeling of the HPA axis: a study of regulatory plasticity in biology. BMC Syst Biol. 2018 Jul 17;12(1):76. doi: 10.1186/s12918-018-0599-1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6050677/ (Full article)

The putative role of oxidative stress and inflammation in the pathophysiology of sleep dysfunction across neuropsychiatric disorders: Focus on chronic fatigue syndrome, bipolar disorder and multiple sclerosis

Abstract:

Sleep and circadian abnormalities are prevalent and burdensome manifestations of diverse neuro-immune diseases, and may aggravate the course of several neuropsychiatric disorders. The underlying pathophysiology of sleep abnormalities across neuropsychiatric disorders remains unclear, and may involve the inter-play of several clinical variables and mechanistic pathways.

In this review, we propose a heuristic framework in which reciprocal interactions of immune, oxidative and nitrosative stress, and mitochondrial pathways may drive sleep abnormalities across potentially neuroprogressive disorders. Specifically, it is proposed that systemic inflammation may activate microglial cells and astrocytes in brain regions involved in sleep and circadian regulation. Activated glial cells may secrete pro-inflammatory cytokines (for example, interleukin-1 beta and tumour necrosis factor alpha), nitric oxide and gliotransmitters, which may influence the expression of key circadian regulators (e.g., the Circadian Locomotor Output Cycles Kaput (CLOCK) gene). Furthermore, sleep disruption may further aggravate oxidative and nitrosative, peripheral immune activation, and (neuro) inflammation across these disorders in a vicious pathophysiological loop.

This review will focus on chronic fatigue syndrome, bipolar disorder, and multiple sclerosis as exemplars of neuro-immune disorders. We conclude that novel therapeutic targets exploring immune and oxidative & nitrosative pathways (p.e. melatonin and molecular hydrogen) hold promise in alleviating sleep and circadian dysfunction in these disorders.

Source: Morris G, Stubbs B, Köhler CA, Walder K, Slyepchenko A, Berk M, Carvalho AF. The putative role of oxidative stress and inflammation in the pathophysiology of sleep dysfunction across neuropsychiatric disorders: Focus on chronic fatigue syndrome, bipolar disorder and multiple sclerosis. Sleep Med Rev. 2018 Apr 4. pii: S1087-0792(17)30152-1. doi: 10.1016/j.smrv.2018.03.007. [Epub ahead of print]  https://www.ncbi.nlm.nih.gov/pubmed/29759891

Patients with chronic fatigue syndrome do not score higher on the autism-spectrum quotient than healthy controls: Comparison with autism spectrum disorder

Abstract:

Clinically, there is an overlap of several symptoms of chronic fatigue syndrome (CFS) and autism spectrum disorder (ASD), including fatigue; brain “fog”; cognitive impairments; increased sensitivity to sound, light, and odour; increased pain and tenderness; and impaired emotional contact.

Adults with CFS (n = 59) or ASD (n = 50) and healthy controls (HC; n = 53) were assessed with the Autism-Spectrum Quotient (AQ) in a cross-sectional study. Non-parametric analysis was used to compare AQ scores among the groups. Univariate analysis of variance (ANCOVA) was used to identify if age, sex, or diagnostic group influenced the differences in scores. Patients with ASD scored significantly higher on the AQ than the CFS group and the HC group. No differences in AQ scores were found between the CFS and HC groups. AQ results were influenced by the diagnostic group but not by age or sex, according to ANCOVA. Despite clinical observations of symptom overlap between ASD and CFS, adult patients with CFS report few autistic traits in the self-report instrument, the AQ. The choice of instrument to assess autistic traits may influence the results.

Source: Bileviciute-Ljungar I, Maroti D, Bejerot S. Patients with chronic fatigue syndrome do not score higher on the autism-spectrum quotient than healthy controls: Comparison with autism spectrum disorder. Scand J Psychol. 2018 May 8. doi: 10.1111/sjop.12451. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/29738079

Abnormal rheological properties of red blood cells as a potential marker of Gulf War Illness: A preliminary study

Editor’s comment: In the 1980s, L. O. Simpson studied abnormally shaped red blood cells in patients with ME, which he published in a paper, “Nondiscocyte Erythrocytes in Myalgic Encephalomyelitis.” He later summarized his findings in a paper entitled “The Results from Red Cell Shape Analyses of Blood Samples From Members of Myalgic Encephalomyelitis Organisations in Four Countries.” You can read it HERE.

Abstract:

BACKGROUND: Veterans with Gulf War Illness (GWI) experience chronic symptoms that include fatigue, pain, and cognitive impairment. This symptom cluster may be the consequence of impaired tissue oxygen delivery due to red blood cell (RBC) dysfunction.

OBJECTIVE: The purpose of this preliminary study was to determine whether the microrheological behavior of RBCs is altered in GWI.

METHODS: We recruited 17 cases of GWI (GWI+) and 10 age matched controls (GWI-), and examined RBC deformability and aggregation via ektacytometry along with measurement of complete blood counts.

RESULTS: RBCs were more deformable in GWI+, as indicated by higher elongation indices particularly at higher shear stress values (5.33, 9.49, and 16.89) when compared to GWI-. Aggregation formation, stability and kinetics were similar between GWI+and GWI-. Complete blood counts were also similar, with the exception of mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and RBC distribution width (RDW) which was elevated in GWI+.

CONCLUSIONS: In this preliminary study, we observed increased deformability along with increased MCH, MCHC and RDW in veterans with GWI+, which may contribute to the symptomatology of GWI. Further research is required to confirm our findings and the role of RBC microrheology in GWI.

Source: Falvo MJ, Chen Y, Klein JC, Ndirangu D, Condon MR. Abnormal rheological properties of red blood cells as a potential marker of Gulf War Illness: A preliminary study. Clin Hemorheol Microcirc. 2018;68(4):361-370. doi: 10.3233/CH-170262. https://www.ncbi.nlm.nih.gov/pubmed/29660926

Differentiating Multiple Sclerosis from Myalgic Encephalomyelitis and Chronic Fatigue Syndrome

Abstract:
Multiple Sclerosis (MS), Myalgic Encephalomyelitis (ME), and Chronic Fatigue syndrome are debilitating chronic illnesses, with some overlapping symptoms. However, few studies have compared and contrasted symptom and disability profiles for these illnesses for the purpose of further differentiating them. The current study was an online self-report survey that compared symptoms from a sample of individuals with MS (N = 120) with a sample of individuals with ME or CFS (N = 269). Respondents completed the self-report DePaul Symptom Questionnaire. Those individuals with ME or CFS reported significantly more functional limitations and significantly more severe symptoms than those with MS. The implications of these findings are discussed.

Source: Jason LA, Ohanian D, Brown A, Sunnquist M, McManimen S, Klebek L, Fox P, Sorenson M. Differentiating Multiple Sclerosis from Myalgic Encephalomyelitis and Chronic Fatigue Syndrome. Insights Biomed. 2017;2(2). pii: 11. doi: 10.21767/2572-5610.10027. Epub 2017 Jun 12.

On chronic fatigue syndrome and nosological categories

Abstract:

Chronic fatigue syndrome (CFS) is a heterogeneous disease which presents with pronounced disabling fatigue, sleep disturbances, and cognitive impairment that negatively affects patients’ functional capability. CFS remains a poorly defined entity and its etiology is still in question. CFS is neither a novel diagnosis nor a new medical condition. From as early as the eighteenth century, a constellation of perplexing symptoms was observed that resembled symptoms of CFS. Commencing with “febricula” and ending with CFS, many names for the disease were proposed including neurocirculatory asthenia, atypical poliomyelitis, Royal Free disease, effort syndrome, Akureyri disease, Tapanui disease, chronic Epstein-Barr virus syndrome, and myalgic encephalitis. To date, it remains unclear whether CFS has an autoimmune component or is a condition that precedes a full-blown autoimmune disease.

Research suggests that CFS may overlap with other diseases including postural orthostatic tachycardia syndrome (POTS), autoimmune syndrome induced by adjuvants (ASIA), and Sjögren’s syndrome. Additionally, it has been postulated that the earliest manifestations of some autoimmune diseases can present with vague non-specific symptoms similar to CFS. Sometimes only when exposed to a secondary stimulus (e.g., antigen) which could accelerate the natural course of the disease would an individual develop the classic autoimmune disease. Due to the similarity of symptoms, it has been postulated that CFS could simply be an early manifestation of an autoimmune disease. This paper will provide a historical background review of this disease and a discussion of CFS as an entity overlapping with multiple other conditions.

Source: Sharif K, Watad A, Bragazzi NL, Lichtbroun M, Martini M, Perricone C, Amital H, Shoenfeld Y. On chronic fatigue syndrome and nosological categories. Clin Rheumatol. 2018 Feb 7. doi: 10.1007/s10067-018-4009-2. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/29417255