ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

641–660 of 738 studies

E3 PreliminaryCohortPEM unclearCross-Sectional

Consulting patients in setting priorities in Myalgic Encephalomyelitis (M.E.) research: findings from a national on-line survey.

Childs, Nicola, Robinson, Lisa, Chowdhury, Sonya et al.·Research involvement and engagement·2015

Researchers asked over 1,100 people affected by ME/CFS what they thought should be the most important areas for future research. The top priorities were understanding what causes ME/CFS, developing better treatments, and improving how quickly and accurately doctors can diagnose the illness. This study shows that patients have strong, clear opinions about what research funding should focus on.

Post-Exertional Malaise

E3 PreliminaryCohortPEM not requiredCross-Sectional

The Nature of Fatigue in Chronic Fatigue Syndrome.

Olson, Karin, Zimka, Oksana, Stein, Eleanor·Qualitative health research·2015

This study asked 14 people with ME/CFS to describe their experience of fatigue in their own words. Participants identified three different types of tiredness: regular tiredness (before diagnosis), fatigue (during daily activities), and exhaustion (after overexertion). The most helpful strategies people used were pacing activities and taking extended rest periods to manage their symptoms and prevent crashes.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM not requiredMechanistic

Evidence for sensitized fatigue pathways in patients with chronic fatigue syndrome.

Staud, Roland, Mokthech, Meriem, Price, Donald D et al.·Pain·2015

This study tested whether ME/CFS patients have unusually sensitive "fatigue pathways" in their muscles and nerves that overreact to exercise. Researchers had patients and healthy controls do hand exercises, then briefly cut off blood flow to the forearm to trap muscle chemicals in the tissues. ME/CFS patients reported increased fatigue during the blood flow cutoff, while healthy people's fatigue actually decreased—suggesting their muscles and nerves are sending stronger fatigue signals.

Post-Exertional Malaise

E3 PreliminaryCommentaryPEM requiredEditorial

Reflections on the Institute of Medicine's systemic exertion intolerance disease.

Jason, Leonard A, Sunnquist, Madison, Brown, Abigail et al.·Polskie Archiwum Medycyny Wewnetrznej·2015

The Institute of Medicine proposed renaming chronic fatigue syndrome to 'systemic exertion intolerance disease' (SEID) and created new diagnostic criteria. This editorial critiques that change, noting that most patients rejected the new name and the new criteria were not tested on actual patient populations before being recommended. The new criteria may incorrectly identify more people as having the disease while missing key features that define it.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

Capturing the post-exertional exacerbation of fatigue following physical and cognitive challenge in patients with chronic fatigue syndrome.

Keech, Andrew, Sandler, Carolina X, Vollmer-Conna, Ute et al.·Journal of psychosomatic research·2015

This study developed a new questionnaire called the Fatigue and Energy Scale (FES) to measure the specific type of exhaustion that ME/CFS patients experience after physical or mental activity. Researchers talked with 19 patients to understand what their fatigue feels like, then tested the questionnaire with patients doing exercise, driving simulation, and everyday tasks. The results showed that the FES successfully captured both the physical tiredness and mental fog that worsens after activity in ME/CFS.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms.

Twisk, Frank Nm·World journal of methodology·2015

ME and CFS are often treated as the same condition, but they are actually different illnesses with some overlapping symptoms. ME has specific features like muscle weakness, brain fog, heart and circulation problems, and especially a distinctive symptom called post-exertional malaise—where patients feel much worse after even small amounts of activity. Because many ME/CFS symptoms feel subjective, some doctors have questioned whether they are real physical problems, but this article argues that objective medical tests can measure key symptoms and help doctors diagnose these conditions more accurately.

Cognitive ImpairmentPost-Exertional Malaise

E3 PreliminaryCohortPEM not requiredCase-Control

Are stamina and fatigue polar opposites? A case study.

So, Suzanna, Evans, Meredyth, Jason, Leonard A et al.·Journal of prevention & intervention in the community·2015

This study looked at whether fatigue and stamina are opposite sides of the same coin in ME/CFS. The researchers found that some people with ME/CFS have low fatigue but still cannot do much physically, while others have high fatigue that stops them from being active. This suggests that fatigue and stamina may be separate issues, and current diagnostic criteria that focus mainly on fatigue might miss people who have low energy and endurance but don't report severe fatigue.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM unclearMethods-Paper

Variability in Symptoms Complicates Utility of Case Definitions.

McManimen, Stephanie L, Jason, Leonard A, Williams, Yolonda J·Fatigue : biomedicine, health & behavior·2015

This study looked at how ME/CFS is defined and diagnosed across different research centers. Researchers found that when different studies measure key symptoms like post-exertional malaise (feeling worse after activity), unrefreshing sleep, and brain fog, they get very different numbers—suggesting that either different patients are being studied, or researchers are asking questions in different ways. The study concluded that ME/CFS research needs more standardized, consistent methods for measuring symptoms so findings can be compared fairly.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM requiredMechanistic

In silico analysis of exercise intolerance in myalgic encephalomyelitis/chronic fatigue syndrome.

Lengert, Nicor, Drossel, Barbara·Biophysical chemistry·2015

This study used computer models to understand why people with ME/CFS struggle with exercise. The researchers simulated what happens in muscle cells during and after physical activity, focusing on mitochondria—the parts of cells that produce energy. Their model showed that when mitochondrial function is reduced, muscles can't make enough energy (ATP), which causes them to accumulate toxic substances like lactate and acid, and can lead to cell death. Importantly, repeated exercise made this problem much worse in their simulations.

Energy MetabolismPost-Exertional Malaise

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

Validating a measure of myalgic encephalomyelitis/chronic fatigue syndrome symptomatology.

Brown, Abigail A, Jason, Leonard A·Fatigue : biomedicine, health & behavior·2014

This study tested whether a questionnaire called the DePaul Symptom Questionnaire (DSQ) accurately measures the symptoms people with ME/CFS experience. Researchers found that ME/CFS symptoms naturally group into three main categories: problems with the nervous system and immune system, problems with thinking and memory, and a worsening of symptoms after physical activity. The questionnaire was shown to be a reliable tool for identifying and measuring these symptom patterns in ME/CFS patients.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

Mitochondrial dysfunctions in myalgic encephalomyelitis/chronic fatigue syndrome explained by activated immuno-inflammatory, oxidative and nitrosative stress pathways.

Morris, Gerwyn, Maes, Michael·Metabolic brain disease·2014

This study explains how ME/CFS may damage the mitochondria—the energy-producing units inside our cells. The researchers found that inflammation, immune system overactivity, and harmful molecules called oxidative stress can interfere with how mitochondria produce energy (ATP), which is why ME/CFS patients experience extreme fatigue and post-exertional malaise. Low levels of protective vitamins and minerals also make this problem worse.

Immune SystemPost-Exertional Malaise

E3 PreliminaryMechanismPEM requiredObservational

Inability of myalgic encephalomyelitis/chronic fatigue syndrome patients to reproduce VO₂peak indicates functional impairment.

Keller, Betsy A, Pryor, John Luke, Giloteaux, Ludovic·Journal of translational medicine·2014

This study tested whether people with ME/CFS can perform the same on an exercise test when it's repeated the next day, similar to how healthy people typically do. The researchers found that ME/CFS patients performed significantly worse on the second test—using about 14% less oxygen and doing about 12% less work—even though they were trying their hardest both times. This suggests that doing one exercise test may give doctors an unrealistic picture of what ME/CFS patients can actually do.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

Comparing and Contrasting Consensus versus Empirical Domains.

Jason, Leonard A, Kot, Bobby, Sunnquist, Madison et al.·Fatigue : biomedicine, health & behavior·2014

Researchers compared different sets of diagnostic criteria used to identify ME/CFS patients. They looked at criteria developed by expert groups (like the Canadian Consensus Criteria) and compared them to criteria identified through statistical analysis of actual patient data. The study found that the fatigue and post-exertional malaise domain (worsening symptoms after activity) was the best feature for distinguishing ME/CFS patients from healthy people, and that older diagnostic criteria were less accurate.

Post-Exertional Malaise

E3 PreliminaryBehavioralPEM unclearCross-Sectional

Experiences of daily activity in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and their implications for rehabilitation programmes.

Pemberton, Sue, Cox, Diane L·Disability and rehabilitation·2014

This study interviewed 14 people with ME/CFS to understand how they experience daily activities. Researchers found that before becoming ill, most participants were very active and had difficulty taking breaks. When they got sick, they tried to keep pushing themselves to do as much as before, which led to worsening symptoms. The study suggests that rehabilitation programs should take into account people's attitudes toward activity and rest, not just focus on changing what they do.

Post-Exertional Malaise

E3 PreliminaryReviewPEM not requiredReview-Narrative

[Biopersistence and systemic distribution of intramuscularly injected particles: what impact on long-term tolerability of alum adjuvants?].

Gherardi, Romain K, Cadusseau, Josette, Authier, François-jérôme·Bulletin de l'Academie nationale de medecine·2014

This review examines how aluminum-based vaccine adjuvants (immune-boosting ingredients) may rarely cause long-term health problems in susceptible people, including muscle pain, exhaustion, and brain fog that can last years. The researchers found that aluminum particles can travel from the injection site through the body to distant organs and the brain, and that a specific immune protein called MCP-1 may control how much this happens. For most people, aluminum adjuvants are safe, but genetic and environmental differences may make some individuals more vulnerable to prolonged effects.

Immune SystemPost-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

Main neuroendocrine features, diagnosis and therapeutic possibilities in the chronic fatigue syndrome, an underdiagnosed entity.

Amihăesei, Ioana Cristina, Cojocaru, Elena·Revista medico-chirurgicala a Societatii de Medici si Naturalisti din Iasi·2014

ME/CFS is a serious illness marked by extreme tiredness that doesn't improve with rest, along with problems concentrating, pain, and worsening symptoms after activity. Diagnosis requires at least six months of severe fatigue plus four or more other specific symptoms. Current treatments focus on behavioral approaches and pacing rather than medications, though only about 5% of people fully recover, and more than half become unable to work.

Post-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 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 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 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

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Evidence browser

Consulting patients in setting priorities in Myalgic Encephalomyelitis (M.E.) research: findings from a national on-line survey.

The Nature of Fatigue in Chronic Fatigue Syndrome.

Evidence for sensitized fatigue pathways in patients with chronic fatigue syndrome.

Reflections on the Institute of Medicine's systemic exertion intolerance disease.

Capturing the post-exertional exacerbation of fatigue following physical and cognitive challenge in patients with chronic fatigue syndrome.

Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms.

Are stamina and fatigue polar opposites? A case study.

Variability in Symptoms Complicates Utility of Case Definitions.

In silico analysis of exercise intolerance in myalgic encephalomyelitis/chronic fatigue syndrome.

Validating a measure of myalgic encephalomyelitis/chronic fatigue syndrome symptomatology.

Mitochondrial dysfunctions in myalgic encephalomyelitis/chronic fatigue syndrome explained by activated immuno-inflammatory, oxidative and nitrosative stress pathways.

Inability of myalgic encephalomyelitis/chronic fatigue syndrome patients to reproduce VO₂peak indicates functional impairment.

Comparing and Contrasting Consensus versus Empirical Domains.

Experiences of daily activity in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and their implications for rehabilitation programmes.

[Biopersistence and systemic distribution of intramuscularly injected particles: what impact on long-term tolerability of alum adjuvants?].

Main neuroendocrine features, diagnosis and therapeutic possibilities in the chronic fatigue syndrome, an underdiagnosed entity.

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

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

Clinical Practice: Chronic fatigue syndrome.

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

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