Search and filter 6,188 studies by evidence level, diagnostic criteria, PEM status, and research domain. Each entry links to the original source.
Studies sorted by evidence level, then year. Browse by topic instead →
Evidence level (E0–E3) reflects study type and replication, not methodological quality. A weak systematic review still sits at E0. How evidence levels work →
4521–4540 of 6,188 studies
Friedman, Kenneth J, Bateman, Lucinda, Bested, Alison et al.·Frontiers in pediatrics·2019
This editorial discusses recent progress in understanding and treating ME/CFS, particularly in children and young people. The authors highlight important advances in how doctors recognize and care for ME/CFS patients, and emphasize the need for continued research and improved clinical awareness.
Ohba, Takuya, Domoto, Shinichi, Tanaka, Miyu et al.·Biological & pharmaceutical bulletin·2019
Researchers created a mouse model of ME/CFS by repeatedly forcing mice to swim, which produced fatigue-like behaviors similar to the human condition. They found that this stress reduced the activity of an important energy-producing enzyme called PDH in muscle cells. When they treated the mice with a drug that reactivates PDH, the fatigue-like symptoms improved, suggesting this enzyme may be a target for future ME/CFS treatments.
Komaroff, Anthony L·JAMA·2019
This review article examines what scientists currently understand about how ME/CFS develops and affects the body at a cellular level. Researcher Anthony Komaroff synthesizes evidence suggesting that ME/CFS involves problems with energy production in cells, immune system dysfunction, and nervous system abnormalities. The article helps explain why ME/CFS causes such severe fatigue and why patients often feel worse after physical activity.
Kashi, Alex A, Davis, Ronald W, Phair, Robert D·Diagnostics (Basel, Switzerland)·2019
This study proposes a new theory about what might cause ME/CFS based on how the body processes an amino acid called tryptophan. The researchers suggest that if two proteins involved in tryptophan processing don't work properly together, the body could get stuck in a harmful state that causes ME/CFS symptoms. According to their mathematical model, if we could find a way to reset tryptophan levels back to normal, patients might recover.
Fijen, Lauré, Weijmer, Marcel·BMJ case reports·2019
This case report describes an elderly man with ME/CFS who developed serious kidney damage after taking high doses of vitamin C supplements. He also had a pancreatic condition that affected his ability to digest fats properly. The combination of these two factors caused harmful crystal buildup in his kidneys, leading to acute kidney failure that required dialysis treatment.
Devendorf, Andrew R, Jackson, Carly T, Sunnquist, Madison et al.·Journal of health psychology·2019
This study interviewed 13 doctors who treat ME/CFS to understand the challenges they face when trying to measure whether patients are getting better. The researchers found four main areas that make recovery difficult to assess: differences in how the illness affects people at different ages, the fact that ME/CFS shows up differently in different patients, trouble keeping track of patients over time, and practical difficulties in measuring improvement.
Williams, Ashley Mai, Christopher, Gary, Jenkinson, Elizabeth·Journal of health psychology·2019
This study interviewed adults with ME/CFS who rely on others for daily help and explored how this dependency affects their emotional health. Researchers found that people experience several psychological challenges, including feeling like they've lost their independence and identity, struggling with invisible symptoms others don't understand, and worrying about the future. The study suggests that better education for family and friends, improved communication strategies, and accepting the condition can help improve emotional well-being.
Overholser, James C, Beale, Eleanor E·The Journal of nervous and mental disease·2019
This article looks back at a condition called neurasthenia that doctors diagnosed frequently between 1869 and 1930, then largely abandoned. The authors found that many symptoms people with neurasthenia experienced—like exhaustion, mental fog, and physical weakness—are still seen today in conditions like chronic fatigue syndrome (ME/CFS) and fibromyalgia. By understanding neurasthenia's history, modern doctors may better recognize and treat these conditions and improve how they listen to their patients.
Vink, Mark, Vink-Niese, Friso·Diagnostics (Basel, Switzerland)·2019
This review examines how ME/CFS affects people's ability to work and what happens when they try to return to employment. Most patients who continue working do so part-time in less physically demanding roles. The study found that early rest after becoming ill gives patients the best chance of recovery, while forcing themselves to work beyond their capacity often leads to worse outcomes and longer periods away from work.
Pedersen, Maria·Scandinavian journal of pain·2019
This review explains that ME/CFS and chronic pain conditions share important similarities—both involve protective body signals that were helpful in the short term but become problematic when they persist long-term. The authors suggest that our brain's tendency to anticipate and predict threats may play a role in keeping these conditions going, which helps explain why treatments focusing on stress relief and changing thought patterns can sometimes help patients improve.
Bruton, Alisha, Fuller, Leslie·The Permanente journal·2019
This report describes one woman who had both a rare movement disorder (paroxysmal kinesigenic dyskinesia) and chronic fatigue syndrome. When she received weekly injections of vitamins and minerals, her movement disorder symptoms almost completely went away, and she was able to return to her normal daily activities. Genetic testing found several mutations that may help explain why this treatment worked so well for her.
Polli, Andrea, Van Oosterwijck, Jessica, Meeus, Mira et al.·Scandinavian journal of pain·2019
This study explored whether exercise-triggered immune system changes in ME/CFS patients are connected to increased pain sensitivity. Researchers compared immune markers and pain thresholds in ME/CFS patients and healthy people before and after two different types of exercise. They found a link between changes in a immune protein called C4a and pain sensitivity in ME/CFS patients, but this connection was weak and only showed up in some measurements.
Watanabe, Kyosuke, Sasaki, Akihiro T, Tajima, Kanako et al.·Scientific reports·2019
When healthy people become mentally tired from doing difficult thinking tasks, their brains start paying more attention to sad and negative images. This study used computer tasks to measure how people's attention shifts before and after mental exhaustion. The findings suggest that fatigue changes how our brains process sad information, which may help explain why ME/CFS patients often struggle with mood-related challenges.
Martín-Martínez, Eva, Martín-Martínez, Mercedes·Clinical therapeutics·2019
This study looked at three individual ME/CFS patient cases to understand why this disease presents so differently from person to person. The researchers found that patients often wait years for a correct diagnosis because many doctors don't understand ME/CFS well, leading to misdiagnosis and delays in treatment. The study suggests that organizing patient information carefully could help doctors and researchers identify different subtypes of ME/CFS.
Bohne, Victoria J Berdikova, Bohne, Øyvind·Medical hypotheses·2019
This paper proposes that ME/CFS might result from a problem in how the body converts fuel into energy, specifically involving a protein complex called the pyruvate dehydrogenase complex. The researchers suggest that when this complex isn't working properly, it causes lactate (a byproduct of metabolism) to build up suddenly in the body, which could explain the exhaustion and post-exertional malaise (worsening after activity) that patients experience. They propose that the body isn't efficiently recycling important molecules needed for energy production, leading to low energy and fatigue.
Murga, Íñigo, Lafuente, José-Vicente·Atencion primaria·2019
This study traces how ME/CFS has been named and diagnosed over the past 150+ years, from 'neurasthenia' in the 1800s to today's 'post-exertional malaise.' The researchers reviewed medical literature to show how our understanding of this disease has evolved, and highlight that doctors still diagnose it mainly by symptoms and by ruling out other conditions, since no single biological marker has been found.
Haig-Ferguson, Andrew, Loades, Maria, Whittle, Charlotte et al.·Internet interventions·2019
This study looked at whether young people with ME/CFS could receive therapy through video calls (like Skype) instead of traveling to hospital appointments. Researchers interviewed 12 young patients, 6 parents, and 9 healthcare workers about their experiences. Most people found video appointments helpful for reducing travel, though some worried about privacy and felt that something was lost compared to face-to-face meetings.
Jammes, Yves, Retornaz, Frédérique·F1000Research·2019
This study examined how muscles work differently in people with ME/CFS. Researchers found that both the brain's ability to signal muscles and the muscles' ability to respond are impaired in ME/CFS patients. The muscles also appear to have trouble managing harmful molecules called free radicals, especially after exercise, and they may not be producing enough protective proteins that normally shield cells from damage.
Paredes, Stephania, Cantillo, Santiago, Candido, Kenneth D et al.·International journal of molecular sciences·2019
This review article explains how a brain chemical called serotonin affects pain perception, and how female hormones (estrogens) can influence serotonin levels. The authors examine the connection between serotonin, hormones, and several pain conditions including irritable bowel syndrome, fibromyalgia, and migraines. They suggest that targeting serotonin and hormone pathways might offer new treatment options for pain in the future.
Devendorf, Andrew R, Jackson, Carly T, Sunnquist, Madison et al.·Disability and rehabilitation·2019
This study asked ME/CFS doctors what they think it means to truly recover from these illnesses. The researchers found that doctors see recovery as getting back to how a person functioned before they got sick, with all symptoms gone. They also identified a separate category called 'significant improvement,' where patients feel much better and can do more, but still experience some symptoms or need treatment.
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Thematic groupings by clinical question or research area.
PET imaging and other studies providing evidence for brain inflammation in ME/CFS.
NeurologyMetabolomics and mitochondrial function studies revealing energy metabolism disruption.
MetabolismStudies identifying potential biological markers for ME/CFS diagnosis and stratification.
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