ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

1121–1140 of 6,188 studies

E2 ModerateCohortPEM not requiredCross-Sectional

The gut microbial composition is different in chronic fatigue syndrome than in healthy controls.

Prylińska-Jaśkowiak, Monika, Tabisz, Hanna, Kujawski, Sławomir et al.·Scientific reports·2025

Researchers compared the bacteria living in the gut of people with ME/CFS to healthy people and found clear differences. People with ME/CFS had less diverse bacterial communities and different types of bacteria overall. A computer program could accurately tell the difference between ME/CFS and healthy people just by looking at their gut bacteria patterns, suggesting this difference might be important for the illness.

Gut Microbiome

E2 ModerateCohortPEM unclearLongitudinal

Relationship between post-COVID-19 symptoms and daily physical activity.

Sarmento, Antonio, Webber, Sandra, Sargent, Shelley et al.·Frontiers in rehabilitation sciences·2025

This study tracked 18 people with post-COVID symptoms (11 of whom also had ME/CFS-like symptoms) for a week using smartwatches and daily surveys to see how their symptoms related to how much they walked each day. The researchers found that dizziness had the strongest connection to reduced activity—people with more dizziness walked fewer steps both on the same day and the next day. They also discovered that when people had lower fatigue or chest pain the previous day, they were more likely to walk 5,000 or more steps the next day.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredObservational

Identifying commonalities and differences between EHR representations of PASC and ME/CFS in the RECOVER EHR cohort.

Powers, John P, McIntee, Tomas J, Bhatia, Abhishek et al.·Communications medicine·2025

Researchers compared medical records from millions of patients to see how Long COVID (PASC) and ME/CFS are similar and different. They found that both conditions share common symptoms like fatigue, breathing difficulties, and trouble concentrating, but Long COVID tends to have more heart and lung problems, while ME/CFS more often involves pain and sleep issues. These similarities suggest that some treatment approaches might help both conditions.

Pain and SensitizationSleepCognitive Impairment

E2 ModeratePEM unclearBiobank-Resource

Defining a High-Quality Myalgic Encephalomyelitis/Chronic Fatigue Syndrome cohort in UK Biobank.

Samms, Gemma L, Ponting, Chris P·NIHR open research·2025

This study looked at how ME/CFS is identified in UK Biobank, a large database of health information from hundreds of thousands of people. Researchers found that about 1 in 100 UK Biobank participants had some evidence of ME/CFS, but only about one-third had strong, consistent evidence across multiple records. When they accounted for people too ill to participate in the study, they estimated that around 410,000 people in the UK have ME/CFS.

Diagnostics

E2 ModerateCohortPEM unclearCross-Sectional

Deoxygenation Trends and Their Multivariate Association with Self-Reported Fatigue in Post-COVID Syndrome.

Ladek, Anja-Maria, Lucio, Marianna, Weiß, Andreas et al.·Biomedicines·2025

This study looked at oxygen levels in the muscles of 100 people with long COVID and 50 healthy controls while they performed light exercise (squeezing a stress ball). The researchers used a special non-invasive scan called NIRS to measure this. People with long COVID, especially those with post-exertional malaise, showed abnormal oxygen patterns in their muscles compared to healthy people, and this was linked to their fatigue levels.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearObservational

Efficacy of vitamin D replacement therapy on 28 cases of myalgic encephalomyelitis/chronic fatigue syndrome after COVID-19 vaccination.

Kodama, Shinichiro, Konishi, Nafuko, Hirai, Yuriko et al.·Nutrition (Burbank, Los Angeles County, Calif.)·2025

This study looked at 28 patients who developed ME/CFS after COVID-19 vaccination and found that most had very low vitamin D levels. When these patients received vitamin D treatment through diet, sun exposure, and supplements, their vitamin D levels improved and their ME/CFS symptoms significantly decreased—with 82% of patients no longer meeting ME/CFS criteria after treatment. Sleep problems and autonomic symptoms (like heart rate and blood pressure changes) showed the most improvement.

E2 ModerateCohortPEM unclearObservational

Assessing the influence of lived-experience experts on healthcare providers in a virtual community of practice: a qualitative study.

Weaver, Stephanie Sargent, Carry, Monique, Bertolli, Jeanne et al.·Frontiers in health services·2025

This study looked at whether having patients with lived experience of Long COVID and ME/CFS help teach doctors made a real difference in patient care. Researchers tracked what these patient-experts recommended to doctors through online training sessions from 2022-2024, and then asked actual patients if their doctors seemed to apply that advice. The main recommendations focused on validating patients' experiences, showing empathy, helping with referrals, and supporting self-care. Patients reported noticing positive changes in how their doctors treated them, suggesting that including patient-experts in medical education actually works.

Diagnostics

E2 ModerateCohortPEM unclearCross-Sectional

Association between chronic fatigue syndrome/myalgic encephalomyelitis and cardiovascular disease.

Denu, Mawulorm K I, Revoori, Ritika, Eghan, Cherita et al.·Scientific reports·2025

This study found that people with ME/CFS are significantly more likely to have heart and cardiovascular problems compared to people without ME/CFS. Researchers analyzed health data from over 114,000 Americans and discovered that even after accounting for common heart disease risk factors like high blood pressure, diabetes, and smoking, ME/CFS remained strongly linked to cardiovascular disease. The findings suggest that people with ME/CFS should be monitored more closely for heart health issues.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Psychiatric Comorbidities in Fibromyalgia: A Comparison With Chronic Conditions and Healthy Controls.

Avni, Chen, Morr, Maya, Sinai, Dana et al.·The Journal of nervous and mental disease·2025

This study looked at how often mental health conditions like anxiety and depression occur in people with fibromyalgia compared to people with other long-term illnesses and healthy people. Researchers found that fibromyalgia patients had the highest rates of psychiatric conditions overall, with more than half experiencing anxiety and about half experiencing depression. The study suggests that treating fibromyalgia effectively requires addressing both the physical pain and mental health aspects together.

E2 ModerateCohortPEM unclearObservational

Effect of immunoadsorption on clinical presentation and immune alterations in COVID-19-induced and/or aggravated ME/CFS.

Anft, Moritz, Wiemers, Lea, Rosiewicz, Kamil S et al.·Molecular therapy : the journal of the American Society of Gene Therapy·2025

This small study tested whether a blood-cleaning treatment called immunoadsorption could help people with ME/CFS symptoms that developed or worsened after COVID-19. The treatment removed harmful antibodies (immune proteins) from patients' blood, and researchers found it temporarily reduced inflammation markers and improved some brain function tests. However, patients' main ME/CFS symptoms and fatigue scores did not significantly improve, and the harmful antibodies came back within a month.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

Brain-targeted autoimmunity is strongly associated with Long COVID and its chronic fatigue syndrome as well as its affective symptoms.

Almulla, Abbas F, Maes, Michael, Zhou, Bo et al.·Journal of advanced research·2025

This study found that people with Long COVID have unusual immune responses targeting the brain and nerve cells. Researchers measured antibodies (immune proteins) in people with Long COVID and healthy controls, discovering that Long COVID patients have significantly higher levels of antibodies attacking several brain proteins. These brain-targeted immune responses were strongly linked to fatigue severity and mood symptoms like depression and anxiety.

Neuroinflammation

E2 ModerateBehavioralPEM unclearObservational

Co-occurrence of severe fatigue and insomnia: implications for the outcome of cognitive behavioural therapies.

Rauwerda, Nynke L, Kuut, Tanja A, Braamse, Annemarie M J et al.·Behavioural and cognitive psychotherapy·2025

This study looked at whether having both severe fatigue and sleep problems at the same time affects how well cognitive behavioural therapy (CBT) works. Researchers found that CBT was equally effective whether patients had just fatigue, just insomnia, or both together. Interestingly, when one symptom improved during treatment, the other often improved too—but sometimes one symptom stayed even after the other got better.

Sleep

E2 ModerateCohortPEM unclearCross-Sectional

Cognitive Impairments in Two Samples of Individuals with ME/CFS and Long COVID: A Comparative Analysis.

Sirotiak, Zoe, Adamowicz, Jenna L, Thomas, Emily B K·Journal of clinical psychology in medical settings·2025

This study looked at brain fog and concentration problems in people with ME/CFS and long COVID using data from over 27,000 Americans. Researchers found that people with ME/CFS are about 6 times more likely to experience cognitive difficulties like memory and concentration problems compared to people without these conditions, while long COVID increases the risk about 2 times. People who have both ME/CFS and long COVID together face even greater cognitive challenges.

Long COVID Overlap

E2 ModerateCohortPEM not requiredCross-Sectional

Increased galanin-galanin receptor 1 signaling, inflammation, and insulin resistance are associated with affective symptoms and chronic fatigue syndrome due to long COVID.

Al Masoodi, Wasim Talib Mahdi, Radhi, Sami Waheed, Abdalsada, Habiba Khdair et al.·PloS one·2025

This study looked at 90 people, some with Long COVID and some without, to understand why Long COVID patients develop depression, anxiety, and chronic fatigue. Researchers measured several substances in the blood related to inflammation and metabolism. They found that people with Long COVID had higher levels of inflammatory markers and abnormal insulin function, and these changes were linked to their mood and fatigue symptoms.

NeuroinflammationEnergy MetabolismImmune System

E2 ModerateCohortPEM not requiredCase-Control

Affective and chronic fatigue symptoms are associated with serum neuronal damage markers in Parkinson's disease.

Al-Hakeim, Hussein Kadhem, Khudhair, Hayder Naji, Ranaei-Siadat, Sayed-Omid et al.·Scientific reports·2025

This study looked at people with Parkinson's disease who also experienced depression and extreme fatigue, similar to ME/CFS. Researchers found that certain proteins in the blood that signal brain cell damage were elevated in these patients, and these proteins were connected to inflammation, blood sugar problems, and the mood and fatigue symptoms they experienced.

NeuroinflammationImmune System

E2 ModerateCohortPEM not requiredCase-Control

Persistent symptoms and clinical findings in adults with post-acute sequelae of COVID-19/post-COVID-19 syndrome in the second year after acute infection: A population-based, nested case-control study.

Peter, Raphael S, Nieters, Alexandra, Göpel, Siri et al.·PLoS medicine·2025

This study followed nearly 1,000 people who had long-term COVID symptoms for over a year to see who improved and who stayed sick. Researchers found that about two-thirds of patients still had symptoms in the second year after infection, with fatigue, breathing problems, and thinking difficulties being the most common complaints. People who got better tended to have had milder initial infections and were more educated, while those who stayed sick were more likely to be overweight and have had specialist medical care or rehabilitation.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Small fiber neuropathy in the post-COVID condition and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Clinical significance and diagnostic challenges.

Azcue, Naiara, Teijeira-Portas, Sara, Tijero-Merino, Beatriz et al.·European journal of neurology·2025

This study found that both long-COVID patients and people with ME/CFS show signs of damage to small nerve fibers in the eyes and altered sensation to heat, compared to healthy people. Researchers used specialized imaging and tests to measure nerve fiber structure and how well patients could detect temperature changes. The findings suggest that small fiber nerve damage may contribute to symptoms like pain and abnormal sensations in these conditions.

Autonomic Nervous System

E2 ModerateCohortPEM requiredCross-Sectional

Exploratory study on autoantibodies to arginine-rich human peptides mimicking Epstein-Barr virus in women with post-COVID and myalgic encephalomyelitis/chronic fatigue syndrome.

Hoheisel, Friederike, Fleischer, Kathrin Maria, Rubarth, Kerstin et al.·Frontiers in immunology·2025

This study looked for certain antibodies in the blood of women with post-COVID and ME/CFS that might mistakenly attack the body's own proteins. The researchers found that patients with these conditions had more of these problematic antibodies than healthy people, and these antibodies were linked to common ME/CFS symptoms like fatigue, brain fog, pain, and autonomic problems. The results suggest that a virus (EBV) may trigger the immune system to attack human proteins that look similar to viral proteins.

Pain and SensitizationAutonomic Nervous SystemCognitive Impairment

E2 ModerateCohortPEM requiredLongitudinal

Sustained illness burden over time among Australians with myalgic encephalomyelitis/chronic fatigue syndrome.

Weigel, Breanna, Eaton-Fitch, Natalie, Thapaliya, Kiran et al.·PloS one·2025

This Australian study followed 32 people with ME/CFS over one year to document how the illness affects their lives. Participants reported an average of 30 symptoms at each check-in, with no improvement over the year, and their quality of life was significantly worse than the general population. The findings show that ME/CFS causes sustained, long-term disability that requires better support and recognition from Australian healthcare and disability services.

E2 ModerateCohortPEM requiredCross-Sectional

The association of fatigue and pain with cognitive test performance in patients with myalgic encephalomyelitis/chronic fatigue syndrome.

Oosterman, Joukje M, van der Schaaf, Marieke, de Kleijn, Willemien P E et al.·Journal of psychosomatic research·2025

This study looked at how fatigue and pain affect thinking and memory problems in people with ME/CFS. Researchers tested 1,375 patients on tasks like reaction time and attention, and found that both fatigue severity and pain severity were linked to worse cognitive performance. The effects were stronger in older patients, suggesting that age may play a role in how much fatigue and pain impact thinking abilities.

Pain and SensitizationCognitive Impairment

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The gut microbial composition is different in chronic fatigue syndrome than in healthy controls.

Relationship between post-COVID-19 symptoms and daily physical activity.

Identifying commonalities and differences between EHR representations of PASC and ME/CFS in the RECOVER EHR cohort.

Defining a High-Quality Myalgic Encephalomyelitis/Chronic Fatigue Syndrome cohort in UK Biobank.

Deoxygenation Trends and Their Multivariate Association with Self-Reported Fatigue in Post-COVID Syndrome.

Efficacy of vitamin D replacement therapy on 28 cases of myalgic encephalomyelitis/chronic fatigue syndrome after COVID-19 vaccination.

Assessing the influence of lived-experience experts on healthcare providers in a virtual community of practice: a qualitative study.

Association between chronic fatigue syndrome/myalgic encephalomyelitis and cardiovascular disease.

Psychiatric Comorbidities in Fibromyalgia: A Comparison With Chronic Conditions and Healthy Controls.

Effect of immunoadsorption on clinical presentation and immune alterations in COVID-19-induced and/or aggravated ME/CFS.

Brain-targeted autoimmunity is strongly associated with Long COVID and its chronic fatigue syndrome as well as its affective symptoms.

Co-occurrence of severe fatigue and insomnia: implications for the outcome of cognitive behavioural therapies.

Cognitive Impairments in Two Samples of Individuals with ME/CFS and Long COVID: A Comparative Analysis.

Increased galanin-galanin receptor 1 signaling, inflammation, and insulin resistance are associated with affective symptoms and chronic fatigue syndrome due to long COVID.

Affective and chronic fatigue symptoms are associated with serum neuronal damage markers in Parkinson's disease.

Persistent symptoms and clinical findings in adults with post-acute sequelae of COVID-19/post-COVID-19 syndrome in the second year after acute infection: A population-based, nested case-control study.

Small fiber neuropathy in the post-COVID condition and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Clinical significance and diagnostic challenges.

Exploratory study on autoantibodies to arginine-rich human peptides mimicking Epstein-Barr virus in women with post-COVID and myalgic encephalomyelitis/chronic fatigue syndrome.

Sustained illness burden over time among Australians with myalgic encephalomyelitis/chronic fatigue syndrome.

The association of fatigue and pain with cognitive test performance in patients with myalgic encephalomyelitis/chronic fatigue syndrome.

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