Neuroimmunology: What Role for Autoimmunity, Neuroinflammation, and Small Fiber Neuropathy in Fibromyalgia, Chronic Fatigue Syndrome, and Adverse Events after Human Papillomavirus Vaccination?

Abstract:

Fibromyalgia is a disorder characterized by chronic widespread pain and non-pain symptoms, such as fatigue, dysautonomia, and cognitive and sleep disturbances. Its pathogenesis and treatment continue to be the subject of debate. We highlight the role of three mechanisms-autoimmunity, neuroinflammation, and small fiber neuropathy in the pathogenesis of the disease. These mechanisms are shown to be closely interlinked (also on a molecular level), and the review considers the implementation of this relationship in the search for therapeutic options.

We also pay attention to chronic fatigue syndrome, which overlaps with fibromyalgia, and propose a concept of “autoimmune hypothalamopathy” for its pathogenesis. Finally, we analyze the molecular mechanisms underlying the neuroinflammatory background in the development of adverse events following HPV vaccination and suggesting neuroinflammation, which could exacerbate the development of symptoms following HPV vaccination (though this is hotly debated), as a model for fibromyalgia pathogenesis.

Source: Ryabkova VA, Churilov LP, Shoenfeld Y. Neuroimmunology: What Role for Autoimmunity, Neuroinflammation, and Small Fiber Neuropathy in Fibromyalgia, Chronic Fatigue Syndrome, and Adverse Events after Human Papillomavirus Vaccination? Int J Mol Sci. 2019 Oct 18;20(20). pii: E5164. doi: 10.3390/ijms20205164. https://www.mdpi.com/1422-0067/20/20/5164 (Full article)

Brain studies show chronic fatigue syndrome and Gulf War illness are distinct conditions

CHICAGO (October 23, 2019) — Gulf War Illness (GWI) and chronic fatigue syndrome (CFS) share symptoms of disabling fatigue, pain, systemic hyperalgesia (tenderness), negative emotion, sleep and cognitive dysfunction that are made worse after mild exertion (postexertional malaise). Now, neuroscientists at Georgetown University Medical Center have evidence, derived from human brain studies, that GWI and CFS are two distinct disorders that affect the brain in opposing ways.

The findings, presented in two related studies at the annual meeting of the Society for Neuroscience (SFN) in Chicago, offer a new perspective on neurotoxicity and suggest that methods to effectively diagnose and treat these disorders could be developed, says the studies’ senior author, James Baraniuk, MD, a Georgetown professor of medicine.

GWI affects veterans of the 1990-1991 Persian Gulf War who were exposed to a toxic environment of nerve agents, pesticides and other neurotoxins, while the etiology of CFS is unknown. The overlapping symptoms suggest they may share some common mechanisms of disease.

Baraniuk was first to find unique physical changes in the brains of patients with GWI, and he and his colleagues have also found changes in brain chemistry between GWI and CFS. “This new work further emphasizes that chronic fatigue syndrome and Gulf War Illness are two very real, and very distinct, diseases of the brain,” he says.

The two SFN studies were led by investigators in Baraniuk’s lab. One, being presented by neuroscientist Stuart Washington, PhD, details how specific areas in the brain are affected by the disorders, and the second, led by student Haris Pepermintwala, MS, takes a deep dive into one of those areas, the brain stem, to illustrate the degree to which these conditions have differing effects.

Chronic fatigue syndrome/myalgic encephalomyelitis affects between 836,000 and 2.5 million Americans, according to a 2015 report by the National Academy of Medicine. Gulf War Illness developed in about one-third of the 697,000 veterans deployed to the 1990-1991 Persian Gulf War. Baraniuk says that during Operation Desert Storm, these veterans were exposed to combinations of nerve agents, pesticides and other toxic chemicals that may have triggered the chronic pain and cognitive and gastrointestinal problems.

Both GWI and CFS share common features: cognitive dysfunction, pain and fatigue primarily following physical exercise. To determine how these conditions affect brain function, investigators studied neuronal activation using functional MRI (fMRI) during a cognitive task a day before and a day after bicycle exercise stress tests in their different groups: 38 CFS patients, 80 GWI patients, and a control group of 23 healthy sedentary volunteers. Brain activation during a working memory task was compared between the pre- and post-exercise fMRI studies, and between CFS and GWI groups.

Before exercise, brain activation was similar between groups. However, after exercise the CFS group showed significantly increased activation of the midbrain, while GWI had the opposite effect, with decreased activation in this vital region of the arousal network. CFS also had increased activation in the insula. In contrast, GWI, but not CFS, had a decrease in activation of the cerebellum after exercise. The findings show that specific brain regions acted in opposing ways, representing a differentiation between GWI and CFS.

While these areas are involved in pain perception, among their many other tasks, “this doesn’t mean more or less activity is directly related to pain,” says Washington. “What it does show is that the two conditions are distinct from each other and involve different cellular/molecular mechanisms.”

The second study, led by Pepermintwala, looked more closely at specific regions within the brain stem and confirmed that CFS had significantly increased activation during the cognitive task after the exercise provocations, while GWI had significantly reduced activation.

These regions are involved in vital functions for instantaneous assessments of threats, predator-prey decisions, arousal, modulation of chronic pain, sleep and other neurobehavioral functions, Pepermintwala says. But after exercise, the CFS group had significantly increased activity in the majority of regions evaluated, while the GWI patients experienced significantly decreased activation.

The results support other research, conducted post-mortem in veterans with PTSD, suggesting that the brain stem in these veterans may have physical abnormalities, such as a loss of neurons, Pepermintwala says. “The midbrain is affected by the exercise and cognitive challenges, but CFS and GWI react in opposite ways, showing that they are related, but distinctly different disorders.”

For the study led by Washington, additional co-authors include Rakib Rahan, Richard Garner, Destie Provenzano, Kristina Zajur, Florencia Martinez Addiego, John VanMeter and Baraniuk.

For the study led by Pepermintwala, additional co-authors include Washington, Addiego, Rayhan and Baraniuk.

The authors report having no personal financial interests related to the studies.

These studies were supported by funding from The Sergeant Sullivan Circle, Barbara Cottone, Dean Clarke Bridge Prize, Department of Defense Congressionally Directed Medical Research Program (W81XWH-15-1-0679 and W81-XWH-09-1-0526), and the National Institute of Neurological Disorders and Stroke (R21NS088138 and RO1NS085131). The project has been funded in whole or in part with federal funds (UL1TR000101 previously UL1RR031975) from the National Center for Advancing Translational Sciences, National Institutes of Health, through the Clinical and Translational Science Awards Program.

Clinical efficacy of neurometabolic therapy of dissomical disorders in asthenic syndrome

Abstract:

AIM: To analyze the efficacy of cytoflavin in the complex treatment of sleep disorders in asthenic syndrome.

MATERIAL AND METHODS: One hundred patients with sleep disorders and asthenic syndrome of various etiology and severity were studied. The patients were divided into three groups depending on the type of therapy: the first group received intravenous infusions of cytoflavin for 10 days; the second group, in addition to cytoflavin, received per os melatonin (3 mg or 5 mg) at bedtime; the third group in addition to cytoflavin received per os zopiclone (7.5 mg) at bedtime.

RESULTS: On the 14th day of the study, a decrease in severity or complete relief of asthenia manifestations (according to the SHAS scale) and, accordingly, improvement or normalization of sleep in 97% of patients was found. At the same time, during polysomnographic study, the data obtained are characteristic for improving the quality of sleep phases mainly in the first and second groups of patients and, to a lesser extent, in the third group.

CONCLUSION: Cytoflavin effectively suppresses the main manifestations of asthenic syndrome, including sleep disorders.

Source: Esipov AV, Ivolgin AF, Khritinin DF, Katenko SV, Kazakov SP, Karakozov AG, Kalyagin IE, Levchenko OB, Molodova AI. Clinical efficacy of neurometabolic therapy of dissomical disorders in asthenic syndrome. Zh Nevrol Psikhiatr Im S S Korsakova. 2019;119(9):46-51. doi: 10.17116/jnevro201911909146. [Article in Russian; Abstract available in Russian from the publisher] https://www.ncbi.nlm.nih.gov/pubmed/31626218

Editorial: Advances in ME/CFS Research and Clinical Care

Editorial:

Advances in ME/CFS Research and Clinical Care spotlights Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a maligned, stigmatized, under-researched disease, which lacks a definitive, objective clinical test for its diagnosis, and definitive palliative and curative treatments. A few brave physicians attempt to alleviate the suffering of the afflicted. They rely upon the patients’ symptoms to guide them. Physicians can provide symptomatic relief and improve upon patients’ abnormal physiological and metabolic parameters by intervening to cause the latter to approach normal limits.

Documented to be more severely disabling than HIV-AIDS, ME/CFS receives disturbingly little funding in the United States and around the world. ME/CFS patients constitute an identifiable, underserved population that is in need of the recognition which would raise them from their current, underserved or non-served patient status into the mainstream of healthcare worldwide. ME/CFS is a common disease worldwide, affecting approximately 1 percent of the world’s population.

You can read the rest of this article HERE.

Source: Friedman KJ, Bateman L, Bested A, Nahle Z. Editorial: Advances in ME/CFS Research and Clinical Care. Front Pediatr. 2019 Sep 18;7:370. doi: 10.3389/fped.2019.00370. eCollection 2019. https://www.frontiersin.org/articles/10.3389/fped.2019.00370/full (Full article)

Open Trial of Vitamin B12 Nasal Drops in Adults With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Comparison of Responders and Non-Responders

Abstract:

Introduction: A recent study reported a favorable effect of vitamin B12 injections/oral folic acid support in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) patients. Recently, vitamin B12 nasal drops were developed as an alternative to the vitamin B12 injections. As no data are available on efficacy of this formulation, we studied vitamin B12 serum levels, the physical activity scale of the RAND-36, the number of steps on an activity meter, and the fatigue and concentration scales of the CIS20r questionnaires, before and after 3 months of treatment in ME/CFS patients.

Methods and Results: Fifty-one patients completed all measurements. Forty-four were female. Mean age was 42 years, and mean disease duration was 16 years. Median vitamin B12 levels before treatment were 328 (244-429) pmol/l, and 973 (476-1,476) pmol/l after treatment.

Thirty-four patients reported a favorable response to treatment. In the non-responders, only a small but significant increase in vitamin B12 levels was observed. In contrast, in responders, the number of steps, the physical activity scale of the RAND-36, and the vitamin B12 serum levels increased significantly. The CIS20r fatigue scale decreased significantly, and the CIS20r concentration scale was unchanged.

Conclusions: Nasal drop vitamin B12 administration resulted in a significant increase in vitamin B12 serum levels and therefore may be effective. This pilot study suggest that the nasal drops may be used as an alternative to injections because two thirds of ME/CFS patients reported a positive effect, accompanied by an increased number of steps, improvement of the RAND-36 physical functioning scale and the CIS20r fatigue scale, and a significant increase in serum vitamin B12 levels.Copyright © 2019 van Campen, Riepma and Visser.

Source: van Campen CLM, Riepma K, Visser FC. Open Trial of Vitamin B12 Nasal Drops in Adults With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Comparison of Responders and Non-Responders. Front Pharmacol. 2019 Sep 20;10:1102. doi: 10.3389/fphar.2019.01102. eCollection 2019. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6764214/ (Full article)

Neuroinflammation disorders exacerbated by environmental stressors

Abstract:

Neuroinflammation is a condition characterized by the elaboration of proinflammatory mediators within the central nervous system. Neuroinflammation has emerged as a dominant theme in contemporary neuroscience due to its association with neurodegenerative disease states such as Alzheimer’s disease, Parkinson’s disease and Huntington’s disease.

While neuroinflammation often is associated with damage to the CNS, it also can occur in the absence of neurodegeneration, e.g., in association with systemic infection. The “acute phase” inflammatory response to tissue injury or infections instigates neuroinflammation-driven “sickness behavior,” i.e. a constellation of symptoms characterized by loss of appetite, fever, muscle pain, fatigue and cognitive problems. Typically, sickness behavior accompanies an inflammatory response that resolves quickly and serves to restore the body to homeostasis. However, recurring and sometimes chronic sickness behavior disorders can occur in the absence of an underlying cause or attendant neuropathology.

Here, we review myalgic enchepalomyelitis/chronic fatigue syndrome (ME/CFS), Gulf War Illness (GWI), and chemobrain as examples of such disorders and propose that they can be exacerbated and perhaps initiated by a variety of environmental stressors. Diverse environmental stressors may disrupt the hypothalamic pituitary adrenal (HPA) axis and contribute to the degree and duration of a variety of neuroinflammation-driven diseases.

Source: O’Callaghan JP, Miller DB. Neuroinflammation disorders exacerbated by environmental stressors. Metabolism. 2019 Nov;100S:153951. doi: 10.1016/j.metabol.2019.153951. https://www.ncbi.nlm.nih.gov/pubmed/31610852

Qigong exercise for chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is often overlooked, has unclear etiology and no effective cure except some symptomatic treatments. Additionally, most people with CFS do not seek medical attention. Qigong exercise, an ancient Eastern body-mind-spirit practice, has been long practiced in Chinese communities and may powerfully trigger the self-healing process.

Using full baseline data (n=1409), the average Hong Kong CFS respondent was found to be female, married, 42.5yo, highly educated and employed full-time, experiencing sleep disturbance (~95%), anxiety (>80%), and depressive symptoms (68%).

Here, we summarized our previous studies to evaluate the potential of Qigong as a complementary and alternative therapy for CFS. Two randomized controlled trials were conducted (RCT1 n1=137, RCT2 n2=150). In both trials, extensive online questionnaires allowed individuals with CFS-like illness (i.e., symptoms match CFS, yet without clinical confirmation) to be identified. RCT1 included a 5-week intervention. The intervention in RCT2 was 8weeks. In RCT1 Qigong group had reduced fatigue (P<0.001) and depressive symptoms (P=0.002), and improved telomerase activity (P=0.029). An effective practice regimen was identified (≥3 days/week, at ≥30min/session). Methods were slightly adjusted for RCT2, which replicated RCT1 findings, and further documented improved subjective sleep quality (P=0.008) and adiponectin levels (P<0.05). A significant dose-response relationship was founded.

Thus, Qigong exercise should be recognized as a possible standalone therapy and self-management skill in CFS. Strategies are needed to increase motivation for regular practice and to explore its possibility of self-management skill in brain health. Further clarity would come from studies comparing Qigong with other physical exercises.

Source: Chan JSM, Ng SM, Yuen LP, Chan CLW. Qigong exercise for chronic fatigue syndrome. Int Rev Neurobiol. 2019;147:121-153. doi: 10.1016/bs.irn.2019.08.002. https://www.ncbi.nlm.nih.gov/pubmed/31607352

Differentiating Psychosomatic, Somatopsychic, Multisystem Illnesses, and Medical Uncertainty

Abstract:

There is often difficulty differentiating between psychosomatic, somatopsychic, multisystem illness, and different degrees of medical uncertainty. Uncommon, complex, and multisystem diseases are commonly misdiagnosed. Two case histories are described, and relevant terms differentiating psychosomatic, somatopsychic, and multisystem illnesses are identified, reviewed, and discussed.

Adequate differentiation requires an understanding of the mind/body connection, which includes knowledge of general medicine, psychiatry, and the systems linking the body and the brain. A psychiatric diagnosis cannot be given solely based upon the absence of physical, laboratory, or pathological findings. Medically unexplained symptoms, somatoform disorder, and compensation neurosis are outdated and/or inaccurate terms. The terms subjective, nonspecific, and vague can be used inaccurately. Conversion disorders, functional disorders, psychogenic illness, factitious disorder imposed upon another (Munchausen’s syndrome by proxy), somatic symptom disorder, psychogenic seizures, psychogenic pain, psychogenic fatigue, and delusional parasitosis can be over-diagnosed. Bodily distress disorder and bodily distress syndrome are scientifically unsupported and inaccurate.

Many “all in your head” conditions may be related to the microbiome and the immune system. Better education concerning the interface between medicine and psychiatry and the associated diagnostic nomenclature as well as utilizing clinical judgment and thorough assessment, exercising humility, and maintaining our roots in traditional medicine will help to improve diagnostic accuracy and patient trust.

Source: Bransfield RC, Friedman KJ. Differentiating Psychosomatic, Somatopsychic, Multisystem Illnesses, and Medical Uncertainty. Healthcare (Basel). 2019 Oct 8;7(4). pii: E114. doi: 10.3390/healthcare7040114. https://www.mdpi.com/2227-9032/7/4/114/htm (Full article)

The Efficacy and Safety of Myelophil, an Ethanol Extract Mixture of Astragali Radix and Salviae Radix, for Chronic Fatigue Syndrome: A Randomized Clinical Trial

Abstract:

Background: There is a strong demand for therapeutics to treat chronic fatigue syndrome (CFS), although there are limitations. Myelophil, which is a combination of extracts from Astragali Radix and Salviae Miltiorrhizae Radix, has been clinically used to treat fatigue-related disorders in South Korea. We conducted a randomized controlled clinical trial of Myelophil in patients with CFS and evaluated its efficacy and safety in two hospitals.

Methods: We enrolled 98 participants (M: 38, F: 60) with CFS in a phase 2 trial of oral Myelophil (2 g daily) or placebo for 12 weeks. The primary end point was a change in the Chalder fatigue scale, as scored by a numeric rating scale (NRS). The secondary end points included changes in the visual analogue scale, fatigue severity scale (FSS), and 36-item short-form health survey (SF-36). Biomarkers of oxidative stress and cytokines were evaluated by blood tests.

Results: Ninety-seven participants (48 in the Myelophil group and 49 in the placebo group) completed the trial. An analysis of all participants showed that Myelophil slightly improved fatigue symptoms compared with those of the placebo, but this effect was not statistically significant (p > 0.05 for the NRS, VAS, FSS, and SF-36). By contrast, an analysis of the subpopulation (53 participants, M: 24, F: 29) with severe symptoms (≥63, median NRS value of total participants) showed a statistically significant improvement in fatigue symptoms in the Myelophil group compared with the placebo (p < 0.05 for NRS, FSS, and SF-36). There were no significant changes in the biomarkers for oxidative stress and cytokines before or after the treatment. No Myelophil-related adverse response was observed during the trial.

Conclusion: These results support the hypothesis that Myelophil can be a therapeutic candidate to manage CFS and provide the rationale for its progression to a phase 3 clinical trial.

Clinical Trial Registration: www.ClinicalTrials.gov, identifier KCT0002317

Source: Joung JY, Lee JS, Cho JH, Lee DS, Ahn YC, Son CG. The Efficacy and Safety of Myelophil, an Ethanol Extract Mixture of Astragali Radix and Salviae Radix, for Chronic Fatigue Syndrome: A Randomized Clinical Trial. Front Pharmacol. 2019 Sep 10;10:991. doi: 10.3389/fphar.2019.00991. eCollection 2019. https://www.ncbi.nlm.nih.gov/pubmed/31551788

Exercise therapy for chronic fatigue syndrome

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) or myalgic encephalomyelitis (ME) is a serious disorder characterised by persistent postexertional fatigue and substantial symptoms related to cognitive, immune and autonomous dysfunction. There is no specific diagnostic test, therefore diagnostic criteria are used to diagnose CFS. The prevalence of CFS varies by type of diagnostic criteria used. Existing treatment strategies primarily aim to relieve symptoms and improve function. One treatment option is exercise therapy.

OBJECTIVES: The objective of this review was to determine the effects of exercise therapy for adults with CFS compared with any other intervention or control on fatigue, adverse outcomes, pain, physical functioning, quality of life, mood disorders, sleep, self-perceived changes in overall health, health service resources use and dropout.

SEARCH METHODS: We searched the Cochrane Common Mental Disorders Group controlled trials register, CENTRAL, and SPORTDiscus up to May 2014, using a comprehensive list of free-text terms for CFS and exercise. We located unpublished and ongoing studies through the World Health Organization International Clinical Trials Registry Platform up to May 2014. We screened reference lists of retrieved articles and contacted experts in the field for additional studies.

SELECTION CRITERIA: We included randomised controlled trials (RCTs) about adults with a primary diagnosis of CFS, from all diagnostic criteria, who were able to participate in exercise therapy.

DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection, ‘Risk of bias’ assessments and data extraction. We combined continuous measures of outcomes using mean differences (MDs) or standardised mean differences (SMDs). To facilitate interpretation of SMDs, we re-expressed SMD estimates as MDs on more common measurement scales. We combined dichotomous outcomes using risk ratios (RRs). We assessed the certainty of evidence using GRADE.

MAIN RESULTS: We included eight RCTs with data from 1518 participants.Exercise therapy lasted from 12 weeks to 26 weeks. The studies measured effect at the end of the treatment and at long-term follow-up, after 50 weeks or 72 weeks.

Seven studies used aerobic exercise therapies such as walking, swimming, cycling or dancing, provided at mixed levels in terms of intensity of the aerobic exercise from very low to quite rigorous, and one study used anaerobic exercise. Control groups consisted of passive control, including treatment as usual, relaxation or flexibility (eight studies); cognitive behavioural therapy (CBT) (two studies); cognitive therapy (one study); supportive listening (one study); pacing (one study); pharmacological treatment (one study) and combination treatment (one study).Most studies had a low risk of selection bias. All had a high risk of performance and detection bias.

Exercise therapy compared with ‘passive’ control. Exercise therapy probably reduces fatigue at end of treatment (SMD -0.66, 95% CI -1.01 to -0.31; 7 studies, 840 participants; moderate-certainty evidence; re-expressed MD -3.4, 95% CI -5.3 to -1.6; scale 0 to 33). We are uncertain if fatigue is reduced in the long term because the certainty of the evidence is very low (SMD -0.62, 95 % CI -1.32 to 0.07; 4 studies, 670 participants; re-expressed MD -3.2, 95% CI -6.9 to 0.4; scale 0 to 33).

We are uncertain about the risk of serious adverse reactions because the certainty of the evidence is very low (RR 0.99, 95% CI 0.14 to 6.97; 1 study, 319 participants).Exercise therapy may moderately improve physical functioning at end of treatment, but the long-term effect is uncertain because the certainty of the evidence is very low. Exercise therapy may also slightly improve sleep at end of treatment and at long term. The effect of exercise therapy on pain, quality of life and depression is uncertain because evidence is missing or of very low certainty.

Exercise therapy compared with CBT. Exercise therapy may make little or no difference to fatigue at end of treatment (MD 0.20, 95% CI -1.49 to 1.89; 1 study, 298 participants; low-certainty evidence), or at long-term follow-up (SMD 0.07, 95% CI -0.13 to 0.28; 2 studies, 351 participants; moderate-certainty evidence).

We are uncertain about the risk of serious adverse reactions because the certainty of the evidence is very low (RR 0.67, 95% CI 0.11 to 3.96; 1 study, 321 participants).The available evidence suggests that there may be little or no difference between exercise therapy and CBT in physical functioning or sleep (low-certainty evidence) and probably little or no difference in the effect on depression (moderate-certainty evidence). We are uncertain if exercise therapy compared to CBT improves quality of life or reduces pain because the evidence is of very low certainty.

Exercise therapy compared with adaptive pacing. Exercise therapy may slightly reduce fatigue at end of treatment (MD -2.00, 95% CI -3.57 to -0.43; scale 0 to 33; 1 study, 305 participants; low-certainty evidence) and at long-term follow-up (MD -2.50, 95% CI -4.16 to -0.84; scale 0 to 33; 1 study, 307 participants; low-certainty evidence).

We are uncertain about the risk of serious adverse reactions (RR 0.99, 95% CI 0.14 to 6.97; 1 study, 319 participants; very low-certainty evidence).The available evidence suggests that exercise therapy may slightly improve physical functioning, depression and sleep compared to adaptive pacing (low-certainty evidence). No studies reported quality of life or pain.Exercise therapy compared with antidepressants. We are uncertain if exercise therapy, alone or in combination with antidepressants, reduces fatigue and depression more than antidepressant alone, as the certainty of the evidence is very low. The one included study did not report on adverse reactions, pain, physical functioning, quality of life, sleep or long-term results.

AUTHORS’ CONCLUSIONS: Exercise therapy probably has a positive effect on fatigue in adults with CFS compared to usual care or passive therapies. The evidence regarding adverse effects is uncertain. Due to limited evidence it is difficult to draw conclusions about the comparative effectiveness of CBT, adaptive pacing or other interventions. All studies were conducted with outpatients diagnosed with 1994 criteria of the Centers for Disease Control and Prevention or the Oxford criteria, or both. Patients diagnosed using other criteria may experience different effects.

Source: Larun L, Brurberg KG, Odgaard-Jensen J, Price JR. Exercise therapy for chronic fatigue syndrome. Cochrane Database Syst Rev. 2019 Oct 2;10:CD003200. doi: 10.1002/14651858.CD003200.pub8. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/31577366