Using Plasma Autoantibodies of Central Nervous System Proteins to Distinguish Veterans with Gulf War Illness from Healthy and Symptomatic Controls

Abstract:

For the past 30 years, there has been a lack of objective tools for diagnosing Gulf War Illness (GWI), which is largely characterized by central nervous system (CNS) symptoms emerging from 1991 Gulf War (GW) veterans. In a recent preliminary study, we reported the presence of autoantibodies against CNS proteins in the blood of veterans with GWI, suggesting a potential objective biomarker for the disorder.

Now, we report the results of a larger, confirmatory study of these objective biomarkers in 171 veterans with GWI compared to 60 healthy GW veteran controls and 85 symptomatic civilian controls (n = 50 myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and n = 35 irritable bowel syndrome (IBS)). Specifically, we compared plasma markers of CNS autoantibodies for diagnostic characteristics of the four groups (GWI, GW controls, ME/CFS, IBS).

For veterans with GWI, the results showed statistically increased levels of nine of the ten autoantibodies against neuronal “tubulin, neurofilament protein (NFP), Microtubule Associated Protein-2 (MAP-2), Microtubule Associated Protein-Tau (Tau), alpha synuclein (α-syn), calcium calmodulin kinase II (CaMKII)” and glial proteins “Glial Fibrillary Acidic Protein (GFAP), Myelin Associated Glycoprotein (MAG), Myelin Basic Protein (MBP), S100B” compared to healthy GW controls as well as civilians with ME/CFS and IBS.

Next, we summed all of the means of the CNS autoantibodies for each group into a new index score called the Neurodegeneration Index (NDI). The NDI was calculated for each tested group and showed veterans with GWI had statistically significantly higher NDI values than all three control groups. The present study confirmed the utility of the use of plasma autoantibodies for CNS proteins to distinguish among veterans with GWI and other healthy and symptomatic control groups.

Source: Mohamed B. Abou-Donia, Elizabeth S. Lapadula, Maxine H. Krengel, Emily Quinn, Jessica LeClair, Joseph Massaro, Lisa A. Conboy, Efi Kokkotou, Maria Abreu, Nancy G. Klimas, Daniel D. Nguyen and Kimberly Sullivan.  Using Plasma Autoantibodies of Central Nervous System Proteins to Distinguish Veterans with Gulf War Illness from Healthy and Symptomatic Controls. Brain Sci. 2020, 10(9), 610; https://doi.org/10.3390/brainsci10090610  https://www.mdpi.com/2076-3425/10/9/610/htm (Full text)

Exercise alters brain activation in Gulf War Illness and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Gulf War Illness affects 25–30% of American veterans deployed to the 1990–91 Persian Gulf War and is characterized by cognitive post-exertional malaise following physical effort. Gulf War Illness remains controversial since cognitive post-exertional malaise is also present in the more common Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. An objective dissociation between neural substrates for cognitive post-exertional malaise in Gulf War Illness and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome would represent a biological basis for diagnostically distinguishing these two illnesses.

Here, we used functional magnetic resonance imaging to measure neural activity in healthy controls and patients with Gulf War Illness and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome during an N-back working memory task both before and after exercise. Whole brain activation during working memory (2-Back > 0-Back) was equal between groups prior to exercise. Exercise had no effect on neural activity in healthy controls yet caused deactivation within dorsal midbrain and cerebellar vermis in Gulf War Illness relative to Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients.

Further, exercise caused increased activation among Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients within the dorsal midbrain, left operculo-insular cortex (Rolandic operculum) and right middle insula. These regions-of-interest underlie threat assessment, pain, interoception, negative emotion and vigilant attention. As they only emerge post-exercise, these regional differences likely represent neural substrates of cognitive post-exertional malaise useful for developing distinct diagnostic criteria for Gulf War Illness and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Source: Stuart D Washington, Rakib U Rayhan, Richard Garner, Destie Provenzano, Kristina Zajur, Florencia Martinez Addiego, John W VanMeter, James N Baraniuk, Exercise alters brain activation in Gulf War Illness and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome, Brain Communications, Volume 2, Issue 2, 2020, fcaa070, https://doi.org/10.1093/braincomms/fcaa070 https://academic.oup.com/braincomms/article/2/2/fcaa070/5885074 (Full text)

Machine Learning Detects Pattern of Differences in Functional Magnetic Resonance Imaging (fMRI) Data between Chronic Fatigue Syndrome (CFS) and Gulf War Illness (GWI)

Abstract:

Background: Gulf War Illness (GWI) and Chronic Fatigue Syndrome (CFS) are two debilitating disorders that share similar symptoms of chronic pain, fatigue, and exertional exhaustion after exercise. Many physicians continue to believe that both are psychosomatic disorders and to date no underlying etiology has been discovered. As such, uncovering objective biomarkers is important to lend credibility to criteria for diagnosis and to help differentiate the two disorders.

Methods: We assessed cognitive differences in 80 subjects with GWI and 38 with CFS by comparing corresponding fMRI scans during 2-back working memory tasks before and after exercise to model brain activation during normal activity and after exertional exhaustion, respectively. Voxels were grouped by the count of total activity into the Automated Anatomical Labeling (AAL) atlas and used in an “ensemble” series of machine learning algorithms to assess if a multi-regional pattern of differences in the fMRI scans could be detected.

Results: A K-Nearest Neighbor (70%/81%), Linear Support Vector Machine (SVM) (70%/77%), Decision Tree (82%/82%), Random Forest (77%/78%), AdaBoost (69%/81%), Naïve Bayes (74%/78%), Quadratic Discriminant Analysis (QDA) (73%/75%), Logistic Regression model (82%/82%), and Neural Net (76%/77%) were able to differentiate CFS from GWI before and after exercise with an average of 75% accuracy in predictions across all models before exercise and 79% after exercise. An iterative feature selection and removal process based on Recursive Feature Elimination (RFE) and Random Forest importance selected 30 regions before exercise and 33 regions after exercise that differentiated CFS from GWI across all models, and produced the ultimate best accuracies of 82% before exercise and 82% after exercise by Logistic Regression or Decision Tree by a single model, and 100% before and after exercise when selected by any six or more models. Differential activation on both days included the right anterior insula, left putamen, and bilateral orbital frontal, ventrolateral prefrontal cortex, superior, inferior, and precuneus (medial) parietal, and lateral temporal regions. Day 2 had the cerebellum, left supplementary motor area and bilateral pre- and post-central gyri. Changes between days included the right Rolandic operculum switching to the left on Day 2, and the bilateral midcingulum switching to the left anterior cingulum.

Conclusion: We concluded that CFS and GWI are significantly differentiable using a pattern of fMRI activity based on an ensemble machine learning model.

Source: Provenzano D, Washington SD, Rao YJ, Loew M, Baraniuk J. Machine Learning Detects Pattern of Differences in Functional Magnetic Resonance Imaging (fMRI) Data between Chronic Fatigue Syndrome (CFS) and Gulf War Illness (GWI). Brain Sci. 2020;10(7):E456. Published 2020 Jul 17. doi:10.3390/brainsci10070456 https://www.mdpi.com/2076-3425/10/7/456 (Full text)

Objective Cognitive Performance and Subjective Complaints in Patients With Chronic Q Fever or Q Fever Fatigue Syndrome

Abstract:

Background: Primary aim of this study was to compare cognitive performance of patients with chronic Q fever or Q fever fatigue syndrome (QFS) to matched controls from the general population, while taking performance validity into account. Second, we investigated whether objective cognitive performance was related to subjective cognitive complaints or psychological wellbeing.

Methods: Cognitive functioning was assessed with a neuropsychological test battery measuring the domains of processing speed, episodic memory, working memory and executive functioning. Tests for performance validity and premorbid intelligence were also included. Validated questionnaires were administered to assess self-reported fatigue, depressive symptoms and cognitive complaints.

Results: In total, 30 patients with chronic Q fever, 32 with QFS and 35 controls were included. A high percentage of chronic Q fever patients showed poor performance validity (38%) compared to controls (14%, p = 0.066). After exclusion of participants showing poor performance validity, no significant differences between patients and controls were found in the cognitive domains. QFS patients reported a high level of cognitive complaints compared to controls (41.2 vs 30.4, p = 0.023). Cognitive complaints were not significantly related to cognitive performance in any of the domains for this patient group.

Conclusions: The high level of self-reported cognitive complaints in QFS patients does not indicate cognitive impairment. A large proportion of the chronic Q fever patients showed suboptimal mental effort during neuropsychological assessment. More research into the underlying explanations is needed. Our findings stress the importance of assessing cognitive functioning by neuropsychological examination including performance validity, rather than only measuring subjective cognitive complaints.

Source: Reukers DFM, Aaronson J, van Loenhout JAF, et al. Objective cognitive performance and subjective complaints in patients with chronic Q fever or Q fever fatigue syndrome. BMC Infect Dis. 2020;20(1):397. Published 2020 Jun 5. doi:10.1186/s12879-020-05118-z https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7275429/ (Full text)

 

Chronic Pain Syndromes and Their Laryngeal Manifestations

Abstract:

IMPORTANCE: Fibromyalgia syndrome (FMS), irritable bowel syndrome (IBS), and chronic fatigue syndrome (CFS) are traditionally considered as distinct entities grouped under chronic pain syndrome (CPS) of an unknown origin. However, these 3 disorders may exist on a spectrum with a shared pathophysiology.

OBJECTIVE: To investigate whether the clinical presentation of FMS, IBS, and CFS is similar in a population presenting with voice and laryngeal disorders.

DESIGN, SETTING, AND PARTICIPANTS: This case series was a retrospective review of the medical records and clinical notes of patients treated between January 1, 2016, and December 31, 2017, at the Johns Hopkins Voice Center in Baltimore, Maryland. Patients with at least 1 CPS of interest (FMS, IBS, or CFS) were included (n = 215), along with patients without such diagnoses (n = 4034). Diagnoses, demographic, and comorbidity data were reviewed. Diagnoses related to voice and laryngeal disorders were subdivided into 5 main categories (laryngeal pathology, functional voice disorders, airway problems, swallowing problems, and other diagnoses).

MAIN OUTCOMES AND MEASURES: Prevalence and odds ratios of 45 voice and laryngeal disorders were reviewed. Odds ratios (ORs) were calculated by comparing patients with CPS with control patients.

RESULTS: In total, 4249 individuals were identified; 215 (5.1%) had at least 1 CPS and 4034 (94.9%) were control participants. Patients with CPS were 3 times more likely to be women compared with the control group (173 of 215 [80.5%] vs 2318 of 4034 [57.5%]; OR, 3.156; 95% CI, 2.392-4.296), and the CPS group had a mean (SD) age of 57.80 (15.30) years compared with the mean (SD) age of 55.77 (16.97) years for the control group. Patients with CPS were more likely to present with functional voice disorders (OR, 1.812; 95% CI, 1.396-2.353) and less likely to present with laryngeal pathology (OR, 0.774; 95% CI, 0.610-0.982) or airway problems (OR, 0.474; 95% CI, 0.285-0.789).

CONCLUSIONS AND RELEVANCE: The voice and airway presentation of patients with FMS, IBS, and/or CFS appears to be indistinguishable from each other. This finding suggests that these 3 diseases share upper airway symptoms.

Source: Piersiala K, Akst LM, Hillel AT, Best SR. Chronic Pain Syndromes and Their Laryngeal Manifestations. JAMA Otolaryngol Head Neck Surg. 2020 Apr 30. doi: 10.1001/jamaoto.2020.0530. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/32352483

Post-exertional Malaise in People With Chronic Cancer-Related Fatigue

Abstract:

CONTEXT: Cancer-related fatigue (CRF) is a distressing and persistent sense of tiredness or exhaustion that interferes with usual functioning. Chronic CRF continues for months after curative cancer treatment is complete. Post-exertional malaise (PEM) is a worsening of symptoms after physical or mental activity, with limited investigations in people with chronic CRF.

OBJECTIVES: The purpose of this study was to identify and describe self-reported incidences of PEM in people with chronic CRF.

METHODS: Participants (n = 18) were eligible if they scored ≤34 on the Functional Assessment of Chronic Illness Therapy-Fatigue scale and had a cancer-related onset of fatigue. Participants completed a brief questionnaire to assess PEM during a six-month time frame (the DePaul Symptom Questionnaire-PEM). In addition, a maximal exercise test was used to investigate self-reported symptom exacerbation (via an open-ended questionnaire) after strenuous physical exertion.

RESULTS: On the DePaul Symptom Questionnaire-PEM, three participants met previously defined scoring criteria, which included experiencing moderate to very severe symptoms at least half of the time, worsening of fatigue after minimal effort, plus a recovery duration of >24 hours. Content analysis of responses to open-ended questionnaires identified five people who experienced a delayed recovery and symptoms of PEM after maximal exercise.

CONCLUSION: A subset of people with chronic CRF (up to 33% in this sample) may experience PEM. Exercise specialists and health care professionals working with people with chronic CRF must be aware that PEM may be an issue. Symptom exacerbation after exercise should be monitored, and exercise should be tailored and adapted to limit the potential for harm.

Copyright © 2020 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Source: Twomey R, Yeung ST, Wrightson JG, Millet GY, Culos-Reed SN. Post-exertional Malaise in People With Chronic Cancer-Related Fatigue. J Pain Symptom Manage. 2020 Feb 24. pii: S0885-3924(20)30098-1. doi: 10.1016/j.jpainsymman.2020.02.012. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/32105793

Connectivity differences between Gulf War Illness (GWI) phenotypes during a test of attention

Abstract:

One quarter of veterans returning from the 1990–1991 Persian Gulf War have developed Gulf War Illness (GWI) with chronic pain, fatigue, cognitive and gastrointestinal dysfunction. Exertion leads to characteristic, delayed onset exacerbations that are not relieved by sleep. We have modeled exertional exhaustion by comparing magnetic resonance images from before and after submaximal exercise.

One third of the 27 GWI participants had brain stem atrophy and developed postural tachycardia after exercise (START: Stress Test Activated Reversible Tachycardia). The remainder activated basal ganglia and anterior insulae during a cognitive task (STOPP: Stress Test Originated Phantom Perception). Here, the role of attention in cognitive dysfunction was assessed by seed region correlations during a simple 0-back stimulus matching task (“see a letter, push a button”) performed before exercise. Analysis was analogous to resting state, but different from psychophysiological interactions (PPI).

The patterns of correlations between nodes in task and default networks were significantly different for START (n = 9), STOPP (n = 18) and control (n = 8) subjects. Edges shared by the 3 groups may represent co-activation caused by the 0-back task. Controls had a task network of right dorsolateral and left ventrolateral prefrontal cortex, dorsal anterior cingulate cortex, posterior insulae and frontal eye fields (dorsal attention network). START had a large task module centered on the dorsal anterior cingulate cortex with direct links to basal ganglia, anterior insulae, and right dorsolateral prefrontal cortex nodes, and through dorsal attention network (intraparietal sulci and frontal eye fields) nodes to a default module. STOPP had 2 task submodules of basal ganglia–anterior insulae, and dorsolateral prefrontal executive control regions. Dorsal attention and posterior insulae nodes were embedded in the default module and were distant from the task networks.

These three unique connectivity patterns during an attention task support the concept of Gulf War Disease with recognizable, objective patterns of cognitive dysfunction.

Source: Clarke T, Jamieson JD, Malone P, Rayhan RU, Washington S, VanMeter JW, et al. (2019) Connectivity differences between Gulf War Illness (GWI) phenotypes during a test of attention. PLoS ONE 14(12): e0226481. https://doi.org/10.1371/journal.pone.0226481 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0226481 (Full text)

Systemic Hyperalgesia in Females with Gulf War Illness, Chronic Fatigue Syndrome and Fibromyalgia

Abstract:

Pain is a diagnostic criterion for Gulf War Illness (GWI), Chronic Fatigue Syndrome (CFS), and fibromyalgia (FM). The physical sign of systemic hyperalgesia (tenderness) was assessed in 920 women who were stratified by 2000 Kansas GWI, 1994 CFS, and 1990 FM criteria.

Pressure was applied by dolorimetry at 18 traditional tender points and the average pressure causing pain determined. GWI women were the most tender (2.9 ± 1.6 kg, mean ± SD, n = 70), followed by CFS/FM (3.1 ± 1.4 kg, n = 196), FM (3.9 ± 1.4 kg, n = 56), and CFS (5.8 ± 2.1 kg, n = 170) compared to controls (7.2 ± 2.4 kg, significantly highest by Mann-Whitney tests p < 0.0001, n = 428). Receiver operating characteristics set pressure thresholds of 4.0 kg to define GWI and CFS/FM (specificity 0.85, sensitivities 0.80 and 0.83, respectively), 4.5 kg for FM, and 6.0 kg for CFS.

Pain, fatigue, quality of life, and CFS symptoms were equivalent for GWI, CFS/FM and CFS. Dolorimetry correlated with symptoms in GWI but not CFS or FM. Therefore, women with GWI, CFS and FM have systemic hyperalgesia compared to sedentary controls.

The physical sign of tenderness may complement the symptoms of the Kansas criteria as a diagnostic criterion for GWI females, and aid in the diagnosis of CFS. Molecular mechanisms of systemic hyperalgesia may provide new insights into the neuropathology and treatments of these nociceptive, interoceptive and fatiguing illnesses.

Source: Surian AA, Baraniuk JN. Systemic Hyperalgesia in Females with Gulf War Illness, Chronic Fatigue Syndrome and Fibromyalgia. Sci Rep. 2020 Apr 1;10(1):5751. doi: 10.1038/s41598-020-62771-9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7113257/ (Full text)

Complex syndromes of chronic pain, fatigue and cognitive impairment linked to autoimmune dysautonomia and small fiber neuropathy

Abstract:

Chronic fatigue syndrome, postural orthostatic tachycardia syndrome, complex regional pain syndrome and silicone implant incompatibility syndrome are a subject of debate among clinicians and researchers. Both the pathogenesis and treatment of these disorders require further study.

In this paper we summarize the evidence regarding the role of autoimmunity in these four syndromes with respect to immunogenetics, autoimmune co-morbidities, alteration in immune cell subsets, production of autoantibodies and presentation in animal models. These syndromes could be incorporated in a new concept of autoimmune neurosensory dysautonomia with the common denominators of autoantibodies against G-protein coupled receptors and small fiber neuropathy.

Sjogren’s syndrome, which is a classical autoimmune disease, could serve as a diseases model, illustrating the concept. Development of this concept aims to identify an apparently autoimmune subgroup of the disputable disorders, addressed in the review, which may mostly benefit from the immunotherapy.

Copyright © 2020. Published by Elsevier Inc.

Source: Shoenfeld Y, Ryabkova VA, Sheibenbogen C, Brinth L, Martinez-Lavin M, Ikeda S, Heidecke H, Watad A, Bragazzi NL, Chapman J, Churilov LP, Amital H. Complex syndromes of chronic pain, fatigue and cognitive impairment linked to autoimmune dysautonomia and small fiber neuropathy. Clin Immunol. 2020 Mar 11:108384. doi: 10.1016/j.clim.2020.108384. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/32171889

Syncope and hypermobile joints: Not rare, but rarely diagnosed

Abstract:

Postural orthostatic tachycardia syndrome (POTS) is a chronic, debilitating condition characterized by heterogeneous symptoms, such as lightheadedness, palpitations, pre-syncope, syncope, and weakness or heaviness, especially of the legs. It is frequently associated with hypermobile joints or conditions such as chronic fatigue syndrome, chronic abdominal pain, migraine headache, and diabetes mellitus. Described is a case of POTS, which though it is not rare, is rarely diagnosed. It can be diagnosed quickly with simple methods.

Source: Tahirovic E. Syncope and hypermobile joints: Not rare, but rarely diagnosed. Turk Kardiyol Dern Ars. 2020 Mar;48(2):177-179. doi: 10.5543/tkda.2019.32624. https://archivestsc.com/jvi.aspx?un=TKDA-32624 (Full text)