ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

661–680 of 742 studies

E3 PreliminaryReviewPEM not requiredReview-Narrative

Inflammatory and oxidative and nitrosative stress cascades as new drug targets in myalgic encephalomyelitis and chronic fatigue syndrome.

Maes, Michael·Modern trends in pharmacopsychiatry·2013

This study suggests that ME/CFS involves several overlapping biological problems: inflammation, oxidative stress (cellular damage), and activation of certain immune pathways. The researchers found that ME (characterized by post-exertional malaise) is more severe than CFS, and both conditions have higher levels of inflammatory markers than regular chronic fatigue. Understanding these biological mechanisms may help develop new targeted treatments.

Immune SystemPost-Exertional Malaise

E3 PreliminaryMechanismPEM unclearMechanistic

The effects of exercise on dynamic sleep morphology in healthy controls and patients with chronic fatigue syndrome.

Kishi, Akifumi, Togo, Fumiharu, Cook, Dane B et al.·Physiological reports·2013

This study looked at how sleep changes after exercise in healthy people versus those with ME/CFS. Researchers found that while exercise helped healthy people sleep more deeply and continuously, people with ME/CFS showed different sleep patterns—specifically more disruptions when moving from REM sleep (dream sleep) back to wakefulness. Importantly, these REM sleep disruptions in ME/CFS patients were linked to increased fatigue, pain, and sleepiness the next day.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

Clinical Practice: Chronic fatigue syndrome.

Werker, Charlotte L, Nijhof, Sanne L, van de Putte, Elise M·European journal of pediatrics·2013

This review explains how doctors diagnose ME/CFS in teenagers and describes what we know works to treat it. ME/CFS is a serious illness causing extreme fatigue that doesn't get better with rest, along with other symptoms like trouble thinking clearly, sore throat, and muscle pain. The good news is that a type of talking therapy called cognitive behavioural therapy helps about two-thirds of teenagers with ME/CFS feel better and stay better for years.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

Case definitions and diagnostic criteria for Myalgic Encephalomyelitis and Chronic fatigue Syndrome: from clinical-consensus to evidence-based case definitions.

Morris, Gerwyn, Maes, Michael·Neuro endocrinology letters·2013

Over the past 50+ years, doctors have created many different definitions and diagnostic criteria for ME/CFS, but these criteria were often based on expert opinion rather than scientific evidence. This paper examines why so many different definitions exist and argues that future diagnostic criteria should be built on objective test results (like blood work and brain imaging) rather than just symptoms alone, to better distinguish between ME and CFS as two related but separate conditions.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

Energy Conservation/Envelope Theory Interventions to Help Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Jason, Leonard A, Brown, Molly, Brown, Abigail et al.·Fatigue : biomedicine, health & behavior·2013

This study reviewed research on the Energy Envelope approach, a self-management strategy that helps ME/CFS patients track and limit their daily activities to stay within their available energy level. Rather than pushing through exhaustion, patients learn to pace themselves carefully to avoid crashes. Research shows this approach can reduce symptom flare-ups and improve quality of life for people with ME/CFS.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

Coenzyme Q10 depletion in medical and neuropsychiatric disorders: potential repercussions and therapeutic implications.

Morris, Gerwyn, Anderson, George, Berk, Michael et al.·Molecular neurobiology·2013

This review examines how a natural substance called Coenzyme Q10 (CoQ10) helps cells produce energy and protect themselves from damage. The authors found that low levels of CoQ10 may contribute to ME/CFS and similar conditions that cause fatigue and exhaustion. Studies suggest that taking CoQ10 supplements might help reduce fatigue and improve exercise tolerance in people with ME/CFS, similar to benefits seen in patients with Parkinson's disease and fibromyalgia.

Post-Exertional Malaise

E3 PreliminaryReviewPEM requiredReview-Narrative

A neuro-immune model of Myalgic Encephalomyelitis/Chronic fatigue syndrome.

Morris, Gerwyn, Maes, Michael·Metabolic brain disease·2013

This study proposes a theory about how ME/CFS develops and persists. The researchers suggest that an initial infection triggers the immune system, which then gets stuck in an overactive state even after the infection is cleared. This causes ongoing inflammation, energy problems in cells, and damage to the nervous system, leading to the characteristic symptoms including post-exertional malaise (feeling worse after activity).

NeuroinflammationAutonomic Nervous SystemImmune SystemPost-Exertional Malaise

E3 PreliminaryMechanismPEM unclearMechanistic

Exercise and sleep deprivation do not change cytokine expression levels in patients with chronic fatigue syndrome.

Nakamura, Toru, Schwander, Stephan, Donnelly, Robert et al.·Clinical and vaccine immunology : CVI·2013

Researchers tested whether exercise and sleep loss could trigger increased inflammatory markers in the blood of ME/CFS patients, since many people report that physical activity and poor sleep make their symptoms worse. They found that neither exercise nor sleep deprivation caused the expected increases in inflammatory proteins in people with ME/CFS compared to healthy controls. This suggests that immune activation from these stressors may not be the main reason symptoms worsen with exertion or sleep loss.

Immune SystemPost-Exertional Malaise

E3 PreliminaryReviewPEM requiredReview-Narrative

Myalgic encephalomyelitis/chronic fatigue syndrome and encephalomyelitis disseminata/multiple sclerosis show remarkable levels of similarity in phenomenology and neuroimmune characteristics.

Morris, Gerwyn, Maes, Michael·BMC medicine·2013

This review compares ME/CFS with multiple sclerosis (MS), another recognized neurological disease, and found striking similarities between them. Both conditions cause severe fatigue that worsens with exercise, autonomic problems (like dizziness and heart rate issues), and involve similar patterns of immune system activation and mitochondrial dysfunction (problems with how cells produce energy). The study suggests ME/CFS should be recognized as a genuine neuroimmune illness, similar to MS.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

The relationship between muscle pain and fatigue.

Mastaglia, Frank L·Neuromuscular disorders : NMD·2012

When muscles work hard, pain and fatigue often happen together and can make it harder to exercise. This review examines how pain and tiredness are connected in people with muscle disorders, and explores whether brain stimulation techniques might help reduce both symptoms. Researchers used special magnetic brain stimulation tools to study how the brain controls muscles during exhausting activity.

Post-Exertional Malaise

E3 PreliminaryReviewPEM not requiredReview-Narrative

Pain in patients with chronic fatigue syndrome: time for specific pain treatment?

Nijs, Jo, Crombez, Geert, Meeus, Mira et al.·Pain physician·2012

This review found that pain in ME/CFS is not caused by damaged muscles or joints, but rather comes from how the nervous system processes pain signals—a condition called central sensitization. The study suggests that education about how pain works in ME/CFS, along with cognitive behavioral therapy focused on fatigue, may help patients manage their pain better.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM not requiredObservational

Lack of endogenous pain inhibition during exercise in people with chronic whiplash associated disorders: an experimental study.

Van Oosterwijck, Jessica, Nijs, Jo, Meeus, Mira et al.·The journal of pain·2012

This study compared how the body responds to exercise in people with chronic whiplash injury versus healthy people. Researchers found that pain sensitivity actually increased (got worse) after exercise in whiplash patients, while it decreased (improved) in healthy controls. Importantly, gentle, self-paced exercise caused fewer symptom flare-ups than harder, fixed-intensity exercise, suggesting that how exercise is done matters greatly for people with this condition.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM unclearCross-Sectional

Gene expression alterations at baseline and following moderate exercise in patients with Chronic Fatigue Syndrome and Fibromyalgia Syndrome.

Light, A R, Bateman, L, Jo, D et al.·Journal of internal medicine·2012

This study looked at how genes are turned on and off in people with ME/CFS before and after moderate exercise. Researchers found that about 71% of ME/CFS patients showed increased activity in genes related to nerve signaling and stress response after exercise, which correlated with their fatigue and pain levels. A smaller subgroup (29%) showed a different pattern, with decreased activity in one specific gene, and these patients were more likely to have orthostatic intolerance (dizziness when standing).

BiomarkersPost-Exertional Malaise

E3 PreliminaryTrialPEM requiredRCT

Serotonergic descending inhibition in chronic pain: design, preliminary results and early cessation of a randomized controlled trial.

Meeus, Mira, Ickmans, Kelly, De Clerck, Luc S et al.·In vivo (Athens, Greece)·2011

Researchers wanted to test whether a medication called citalopram (which affects serotonin, a brain chemical) could help reduce pain during exercise in people with ME/CFS and fibromyalgia. However, the study had to stop early because participants experienced significant side effects from the medication and one person with ME/CFS developed severe post-exertional malaise (worsening of symptoms after activity). Because of these problems, the researchers couldn't complete the study or reach any conclusions about whether the treatment worked.

Post-Exertional Malaise

E3 PreliminaryBehavioralPEM unclearCross-Sectional

Finding the right balance of physical activity: a focus group study about experiences among patients with chronic fatigue syndrome.

Larun, Lillebeth, Malterud, Kirsti·Patient education and counseling·2011

This study asked ME/CFS patients about their experiences with physical activity to understand when exercise helped and when it caused problems. The researchers found that patients weren't against activity itself, but what mattered most was having a choice in the type and intensity of exercise, being able to adjust it to their own needs, and having support from healthcare providers. When activity was forced or not personalized, it often led to setbacks and made patients feel they had lost control of their bodies.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM unclearMechanistic

Patients with chronic fatigue syndrome performed worse than controls in a controlled repeated exercise study despite a normal oxidative phosphorylation capacity.

Vermeulen, Ruud C W, Kurk, Ruud M, Visser, Frans C et al.·Journal of translational medicine·2010

This study compared how well people with ME/CFS and healthy controls performed during two exercise tests done 24 hours apart. Patients became exhausted at much lower exercise levels than controls, and performed even worse on the second test. Surprisingly, when researchers tested the energy-producing structures (mitochondria) in patients' blood cells, they appeared to work normally, suggesting the problem may lie elsewhere in the energy production process.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM unclearObservational

Severity of symptom flare after moderate exercise is linked to cytokine activity in chronic fatigue syndrome.

White, Andrea T, Light, Alan R, Hughen, Ronald W et al.·Psychophysiology·2010

This study looked at why some people with ME/CFS feel much worse after exercise. Researchers measured immune chemicals in the blood before and after moderate exercise in people with ME/CFS and healthy controls. They found that patients who experienced severe symptom flare had increased levels of certain immune chemicals 8 hours after exercise, while those with mild flare or healthy people did not show this pattern.

Immune SystemPost-Exertional Malaise

E3 PreliminaryCommentaryPEM unclearEditorial

Perspectives on fatigue from the study of chronic fatigue syndrome and related conditions.

Clauw, Daniel J·PM & R : the journal of injury, function, and rehabilitation·2010

This article explains that ME/CFS is a complex illness with roots in both the body and brain, involving several connected problems at the same time. Researchers have found that ME/CFS shares similar patterns with other conditions like fibromyalgia and irritable bowel syndrome, and involves issues with sleep, pain, cognitive problems, and extreme tiredness after activity. The article describes how inflammation, infection, problems with stress hormones, and nerve signal problems may all contribute to ME/CFS, though we don't yet know which problems matter most.

NeuroinflammationPost-Exertional Malaise

E3 PreliminaryMechanismPEM unclearCross-Sectional

Reduced pressure pain thresholds in response to exercise in chronic fatigue syndrome but not in chronic low back pain: an experimental study.

Meeus, Mira, Roussel, Nathalie A, Truijen, Steven et al.·Journal of rehabilitation medicine·2010

This study compared how people with ME/CFS, chronic back pain, and healthy people respond to exercise. Researchers found that people with ME/CFS have more sensitive pain responses than others, and importantly, their pain sensitivity got worse after light exercise—opposite to what happened in the other groups. This suggests ME/CFS involves different pain processing in the nervous system.

Post-Exertional Malaise

E3 PreliminaryReviewPEM not requiredReview-Narrative

A new hypothesis of chronic fatigue syndrome: co-conditioning theory.

Tanaka, Masaaki, Watanabe, Yasuyoshi·Medical hypotheses·2010

This article proposes a new theory about how ME/CFS might develop: repeated overwork or stress could train your body and brain to respond with fatigue and an urge to rest, similar to how habits form. The authors suggest that once this pattern becomes established, your body may continue producing fatigue even when you're no longer overworking. This theory could eventually lead to new ways of treating ME/CFS.

Post-Exertional Malaise

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Inflammatory and oxidative and nitrosative stress cascades as new drug targets in myalgic encephalomyelitis and chronic fatigue syndrome.

The effects of exercise on dynamic sleep morphology in healthy controls and patients with chronic fatigue syndrome.

Clinical Practice: Chronic fatigue syndrome.

Case definitions and diagnostic criteria for Myalgic Encephalomyelitis and Chronic fatigue Syndrome: from clinical-consensus to evidence-based case definitions.

Energy Conservation/Envelope Theory Interventions to Help Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Coenzyme Q10 depletion in medical and neuropsychiatric disorders: potential repercussions and therapeutic implications.

A neuro-immune model of Myalgic Encephalomyelitis/Chronic fatigue syndrome.

Exercise and sleep deprivation do not change cytokine expression levels in patients with chronic fatigue syndrome.

Myalgic encephalomyelitis/chronic fatigue syndrome and encephalomyelitis disseminata/multiple sclerosis show remarkable levels of similarity in phenomenology and neuroimmune characteristics.

The relationship between muscle pain and fatigue.

Pain in patients with chronic fatigue syndrome: time for specific pain treatment?

Lack of endogenous pain inhibition during exercise in people with chronic whiplash associated disorders: an experimental study.

Gene expression alterations at baseline and following moderate exercise in patients with Chronic Fatigue Syndrome and Fibromyalgia Syndrome.

Serotonergic descending inhibition in chronic pain: design, preliminary results and early cessation of a randomized controlled trial.

Finding the right balance of physical activity: a focus group study about experiences among patients with chronic fatigue syndrome.

Patients with chronic fatigue syndrome performed worse than controls in a controlled repeated exercise study despite a normal oxidative phosphorylation capacity.

Severity of symptom flare after moderate exercise is linked to cytokine activity in chronic fatigue syndrome.

Perspectives on fatigue from the study of chronic fatigue syndrome and related conditions.

Reduced pressure pain thresholds in response to exercise in chronic fatigue syndrome but not in chronic low back pain: an experimental study.

A new hypothesis of chronic fatigue syndrome: co-conditioning theory.

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