ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

561–580 of 737 studies

E3 PreliminaryReviewPEM unclearReview-Narrative

The Role of Kynurenine Pathway and NAD+ Metabolism in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Dehhaghi, Mona, Panahi, Hamed Kazemi Shariat, Kavyani, Bahar et al.·Aging and disease·2022

This review examines how tryptophan, an amino acid we get from food, is processed differently in people with ME/CFS. The body normally converts tryptophan into important substances like serotonin (which affects mood) and NAD+, an energy molecule. The authors propose that this conversion process may become overactive in ME/CFS, depleting NAD+ and making fatigue worse. They suggest that NAD+ supplements might help reduce fatigue and improve quality of life.

Post-Exertional Malaise

E3 PreliminaryGuidelinePEM requiredGuideline

[Recommendation for standardized medical care for children and adolescents with long COVID].

Töpfner, Nicole, Deutsche Gesellschaft für Pädiatrische Infektiologie e. V. (DGPI), Alberer, Martin et al.·Monatsschrift Kinderheilkunde : Organ der Deutschen Gesellschaft fur Kinderheilkunde·2022

This guideline provides doctors with expert recommendations for recognizing and treating long COVID in children and teenagers. It includes screening questions and step-by-step evaluation tools to help identify long COVID cases, as well as guidance on how different medical specialists should work together to care for affected young people. The recommendations are based on the best available evidence, though more research is still needed.

Post-Exertional Malaise

E3 PreliminaryCommentaryPEM unclearEditorial

[Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Who Have Already Visited Some Medical Institutions: The Points of Diagnosis and Treatment].

Shimomura, Tokio·Brain and nerve = Shinkei kenkyu no shinpo·2022

ME/CFS is a debilitating condition characterized primarily by severe fatigue, but doctors currently have no reliable blood tests or biomarkers to definitively diagnose it. This editorial discusses how ME/CFS diagnosis and treatment require specialized medical knowledge, and notes that common treatments like vitamins and herbal medicines have not proven effective. The authors also observed ME/CFS-like symptoms in some COVID-19 patients, which has prompted renewed research into understanding how ME/CFS develops and finding better treatments.

Post-Exertional Malaise

E3 PreliminaryCommentaryPEM requiredEditorial

[Post-COVID syndrome with fatigue and exercise intolerance: myalgic encephalomyelitis/chronic fatigue syndrome].

Renz-Polster, Herbert, Scheibenbogen, Carmen·Innere Medizin (Heidelberg, Germany)·2022

This article explains that ME/CFS is a serious neurological and immune system disease, often triggered by infections like COVID-19, characterized by extreme fatigue lasting at least 6 months and a unique symptom called post-exertional malaise (PEM)—where even mild activity causes symptoms to worsen hours or days later. The authors stress that ME/CFS is a distinct medical condition that should not be confused with ordinary tiredness, and while there is no cure yet, treatment focuses on managing symptoms, addressing related circulation problems, and helping patients conserve energy through pacing.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM requiredMechanistic

Differential Effects of Exercise on fMRI of the Midbrain Ascending Arousal Network Nuclei in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Gulf War Illness (GWI) in a Model of Postexertional Malaise (PEM).

Baraniuk, James N, Amar, Alison, Pepermitwala, Haris et al.·Brain sciences·2022

This study used brain imaging to examine how exercise affects people with ME/CFS and Gulf War Illness. Researchers found that after exercise, the brains of ME/CFS patients showed increased activity in areas that control alertness, mood, pain, and sleep, while Gulf War Illness patients showed the opposite pattern (decreased activity). These findings suggest that ME/CFS and Gulf War Illness affect the brain differently, which may explain why exercise can make symptoms worse in ME/CFS patients.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

Circadian rhythm disruption in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Implications for the post-acute sequelae of COVID-19.

McCarthy, Michael J·Brain, behavior, & immunity - health·2022

This review examines whether disrupted body clocks (circadian rhythms) contribute to ME/CFS symptoms like fatigue, sleep problems, and cognitive difficulties. The authors focus on a specific immune molecule called TGFB that may interfere with the body's natural daily rhythms. They suggest that COVID-19 infections may cause similar circadian disruptions, potentially explaining why some people develop long COVID symptoms that resemble ME/CFS.

Immune SystemPost-Exertional Malaise

E3 PreliminaryMechanismPEM requiredMechanistic

Exosome-associated mitochondrial DNA from patients with myalgic encephalomyelitis/chronic fatigue syndrome stimulates human microglia to release IL-1β.

Tsilioni, Irene, Natelson, Benjamin, Theoharides, Theoharis C·The European journal of neuroscience·2022

This study found that after exercise, patients with ME/CFS have more pieces of DNA from their mitochondria (the energy-producing parts of cells) floating in their blood inside tiny particles called exosomes. When researchers tested these exosomes on immune cells in the lab, they triggered the release of IL-1β, a chemical that causes inflammation in the brain. This suggests that exercise might trigger a chain reaction involving these DNA-carrying particles that could contribute to ME/CFS symptoms.

NeuroinflammationImmune SystemPost-Exertional Malaise

E3 PreliminaryReviewPEM requiredReview-Narrative

Chronic Fatigue Syndrome and Cardiovascular Disease: JACC State-of-the-Art Review.

Natelson, Benjamin H, Brunjes, Danielle L, Mancini, Donna·Journal of the American College of Cardiology·2021

This review examines how ME/CFS affects the heart and blood vessels. Researchers found that people with ME/CFS often have hearts that pump less blood than healthy people, and their blood pressure drops at night. Many also experience rapid heartbeat when standing up. These heart changes may be connected to why people feel worse after physical or mental activity (postexertional malaise).

Post-Exertional Malaise

E3 PreliminaryMechanismPEM requiredMechanistic

Modulatory effects of cognitive exertion on regional functional connectivity of the salience network in women with ME/CFS: A pilot study.

Manca, Riccardo, Khan, Katija, Mitolo, Micaela et al.·Journal of the neurological sciences·2021

This study looked at how the brain responds to mental effort in women with ME/CFS compared to healthy women. Researchers used brain imaging to examine specific networks involved in attention and awareness before and after a cognitive task. Women with ME/CFS experienced increased fatigue and pain after the mental exertion, while a particular brain region (the insula) showed stronger connections to areas controlling reward and decision-making—changes that matched worsening symptoms.

Post-Exertional Malaise

E3 PreliminaryCohortPEM unclearCase-Control

Adolescent and Young Adult ME/CFS After Confirmed or Probable COVID-19.

Petracek, Lindsay S, Suskauer, Stacy J, Vickers, Rebecca F et al.·Frontiers in medicine·2021

This study describes three teenagers and young adults who developed ME/CFS after having COVID-19. All three patients experienced symptoms like dizziness when standing up early in their illness, and by 6 months, all met the clinical criteria for ME/CFS. The researchers noticed several patterns across these patients, including allergies, elevated histamine levels, reduced flexibility, and unusual nerve reflexes—findings that may help identify and treat ME/CFS after COVID-19.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

The development of an instrument to assess post-exertional malaise in patients with myalgic encephalomyelitis and chronic fatigue syndrome.

Jason, Leonard A, Holtzman, Carly S, Sunnquist, Madison et al.·Journal of health psychology·2021

This study created a new questionnaire called the DePaul Post-Exertional Malaise Questionnaire to measure post-exertional malaise (PEM)—the worsening of symptoms that happens after physical or mental activity in ME/CFS patients. Researchers worked with hundreds of patients to develop questions that accurately capture what PEM feels like. Early testing showed the questionnaire works well and connects meaningfully with how much physical activity patients can do.

Post-Exertional Malaise

E3 PreliminaryCommentaryPEM requiredEditorial

A Paradigm for Post-Covid-19 Fatigue Syndrome Analogous to ME/CFS.

Mackay, Angus·Frontiers in neurology·2021

This study proposes that long-term fatigue following COVID-19 works similarly to ME/CFS—both may result from severe infection triggering dysfunction in a brain region called the hypothalamic paraventricular nucleus (PVN). In people genetically susceptible to this condition, the stress from COVID-19 infection could overwhelm this brain center, making it oversensitive to everyday stressors and causing the fatigue, post-exertional malaise, and other symptoms characteristic of ME/CFS.

NeuroinflammationPost-Exertional Malaise

E3 PreliminaryMechanismPEM requiredObservational

Effects of Post-Exertional Malaise on Markers of Arterial Stiffness in Individuals with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Bond, Joshua, Nielsen, Tessa, Hodges, Lynette·International journal of environmental research and public health·2021

This study tested whether intense exercise affects blood vessel function differently in people with ME/CFS compared to healthy individuals. Researchers found that while healthy people's blood vessels became more flexible after exercise, people with ME/CFS did not experience this same improvement, suggesting their blood vessels may not be responding normally to physical stress.

Post-Exertional Malaise

E3 PreliminaryReviewPEM requiredReview-Narrative

A Natural History of Disease Framework for Improving the Prevention, Management, and Research on Post-viral Fatigue Syndrome and Other Forms of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

O'Boyle, Shennae, Nacul, Luis, Nacul, Flavio E et al.·Frontiers in medicine·2021

This study proposes a new way to understand ME/CFS by looking at how the disease develops over time in stages, rather than trying to categorize patients by their different symptoms. The authors suggest that each stage of the disease may need different types of care—early stages might focus on rest and preventing worsening, while later stages need more comprehensive treatment tailored to individual patients. They emphasize that clearer definitions and standards are needed in ME/CFS research to make treatments and policies more reliable.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM requiredMechanistic

Moderate, intermittent voluntary exercise in a model of Gulf War Illness improves cognitive and mood function with alleviation of activated microglia and astrocytes, and enhanced neurogenesis in the hippocampus.

Kodali, Maheedhar, Mishra, Vikas, Hattiangady, Bharathi et al.·Brain, behavior, and immunity·2021

Researchers tested whether moderate exercise three times a week could help rats with a Gulf War Illness-like condition improve their memory, mood, and thinking skills. After 13 weeks, the exercising rats showed better memory and less anxiety, and their brains showed less inflammation and more growth of new brain cells. This suggests that gentle, part-time exercise might help people with similar conditions improve brain function.

NeuroinflammationPost-Exertional Malaise

E3 PreliminaryCohortPEM requiredCase-Control

Three Cases of Severe ME/CFS in Adults.

Williams, Leah R, Isaacson-Barash, Carol·Healthcare (Basel, Switzerland)·2021

This study describes the experiences of three adults living with ME/CFS at different severity levels—moderate, severe, and very severe. The researchers wanted to show how differently this illness affects people and how overwhelming it can be, especially for those who are housebound or bedbound. The study highlights what doctors and healthcare providers can do to better support patients with this complex condition.

Post-Exertional Malaise

E3 PreliminaryReviewPEM requiredReview-Narrative

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): An Overview.

Deumer, Undine-Sophie, Varesi, Angelica, Floris, Valentina et al.·Journal of clinical medicine·2021

ME/CFS is a long-term illness that causes extreme tiredness, worsening of symptoms after activity, and difficulty thinking clearly. Patients experience these symptoms very differently from one another, and currently there are no blood tests or physical exams that can definitively diagnose the condition. This review examines several potential causes, including past infections, genetic factors, hormone imbalances, and changes in gut bacteria, while exploring whether a simple blood test might someday help diagnose ME/CFS.

BiomarkersPost-Exertional Malaise

E3 PreliminaryMechanismPEM unclearObservational

Insights From Invasive Cardiopulmonary Exercise Testing of Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Joseph, Phillip, Arevalo, Carlo, Oliveira, Rudolf K F et al.·Chest·2021

This study used specialized heart and lung testing during exercise to understand why people with ME/CFS struggle with physical activity. Researchers found that ME/CFS patients had two different problems during exercise: some had reduced blood flow returning to the heart, while others couldn't efficiently extract oxygen from their blood. About 31% of patients also showed evidence of small nerve fiber damage in their skin biopsies.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM requiredCross-Sectional

Submaximal Exercise Provokes Increased Activation of the Anterior Default Mode Network During the Resting State as a Biomarker of Postexertional Malaise in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Rayhan, Rakib U, Baraniuk, James N·Frontiers in neuroscience·2021

Researchers used brain imaging to look at what happens in ME/CFS patients' brains after exercise. They found that after submaximal exercise, a specific brain region (the anterior Default Mode Network) showed increased activity in ME/CFS patients but decreased activity in healthy controls. This brain pattern may help explain why ME/CFS patients experience symptom flare-ups after physical activity.

Post-Exertional Malaise

E3 PreliminaryReviewPEM requiredReview-Narrative

COVID-19 and post-infectious myalgic encephalomyelitis/chronic fatigue syndrome: a narrative review.

Poenaru, Sonia, Abdallah, Sara J, Corrales-Medina, Vicente et al.·Therapeutic advances in infectious disease·2021

Some people who recover from COVID-19 continue experiencing prolonged symptoms like fatigue, difficulty breathing, and brain fog for months afterward. These lingering symptoms are remarkably similar to ME/CFS, a chronic illness characterized by severe fatigue that worsens with activity. While COVID-19 could potentially trigger ME/CFS in some people, researchers currently don't have enough evidence to confirm this connection.

Severe MEPost-Exertional Malaise

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The Role of Kynurenine Pathway and NAD+ Metabolism in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

[Recommendation for standardized medical care for children and adolescents with long COVID].

[Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Who Have Already Visited Some Medical Institutions: The Points of Diagnosis and Treatment].

[Post-COVID syndrome with fatigue and exercise intolerance: myalgic encephalomyelitis/chronic fatigue syndrome].

Differential Effects of Exercise on fMRI of the Midbrain Ascending Arousal Network Nuclei in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Gulf War Illness (GWI) in a Model of Postexertional Malaise (PEM).

Circadian rhythm disruption in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Implications for the post-acute sequelae of COVID-19.

Exosome-associated mitochondrial DNA from patients with myalgic encephalomyelitis/chronic fatigue syndrome stimulates human microglia to release IL-1β.

Chronic Fatigue Syndrome and Cardiovascular Disease: JACC State-of-the-Art Review.

Modulatory effects of cognitive exertion on regional functional connectivity of the salience network in women with ME/CFS: A pilot study.

Adolescent and Young Adult ME/CFS After Confirmed or Probable COVID-19.

The development of an instrument to assess post-exertional malaise in patients with myalgic encephalomyelitis and chronic fatigue syndrome.

A Paradigm for Post-Covid-19 Fatigue Syndrome Analogous to ME/CFS.

Effects of Post-Exertional Malaise on Markers of Arterial Stiffness in Individuals with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

A Natural History of Disease Framework for Improving the Prevention, Management, and Research on Post-viral Fatigue Syndrome and Other Forms of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Moderate, intermittent voluntary exercise in a model of Gulf War Illness improves cognitive and mood function with alleviation of activated microglia and astrocytes, and enhanced neurogenesis in the hippocampus.

Three Cases of Severe ME/CFS in Adults.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): An Overview.

Insights From Invasive Cardiopulmonary Exercise Testing of Patients With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Submaximal Exercise Provokes Increased Activation of the Anterior Default Mode Network During the Resting State as a Biomarker of Postexertional Malaise in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

COVID-19 and post-infectious myalgic encephalomyelitis/chronic fatigue syndrome: a narrative review.

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