ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2807 studies

181–200 of 2,807 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Multiple voxel pattern analysis shows associations between chronic fatigue syndrome and cortical atrophy.

Wu, Kang, Zou, Yihuai, Li, Yuanyuan et al.·Frontiers in neuroscience·2025

Researchers used specialized brain imaging to compare 37 people with ME/CFS to 34 healthy people and found that certain areas of the brain's outer layer are thinner in patients with ME/CFS. These thinner areas were linked to how severe their fatigue, pain, and reduced quality of life were. The study suggests that ME/CFS may involve physical changes in brain structure that could help explain why patients experience such debilitating fatigue.

E2 ModerateCohortPEM not requiredCase-Control

Alterations in gut microbiota and associated metabolites in patients with chronic fatigue syndrome.

Cheng, Xinxin, Wang, Wenkuan, Xu, Tingting et al.·Scientific reports·2025

This study looked at the bacteria living in the gut of people with ME/CFS compared to healthy people, and found that ME/CFS patients have fewer types of bacteria and lower levels of helpful compounds called short-chain fatty acids (SCFAs) that bacteria produce. The study found that people with ME/CFS who eat more fiber have higher levels of these beneficial compounds, suggesting diet may help restore some of the bacterial imbalances seen in ME/CFS.

Energy Metabolism

E2 ModerateCohortPEM not requiredCross-Sectional

Association between pre-existing chronic conditions and severity of first SARS-CoV-2 infection symptoms among adults living in Canada: a population-based survey analysis from January 2020 to August 2022.

Cheta, Nicholas, Zakaria, Dianne, Demers, Alain et al.·BMC public health·2025

This Canadian study looked at whether people with long-term health conditions experienced more severe COVID-19 symptoms when they caught the virus. Researchers surveyed over 10,000 adults from 2020 to 2022 and found that certain conditions—like chronic lung disease, high blood pressure, ME/CFS, fibromyalgia, and arthritis—were linked to worse COVID-19 symptoms. This information can help doctors identify who might need extra support or preventive care when facing a COVID-19 infection.

E2 ModerateCohortPEM unclearObservational

Immune Signatures in Post-Acute Sequelae of COVID-19 (PASC) and Myalgia/Chronic Fatigue Syndrome (ME/CFS): Insights from the Fecal Microbiome and Serum Cytokine Profiles.

Tobi, Martin, Chaudhari, Diptaraj, Ryan, Elizabeth P et al.·Biomolecules·2025

Researchers compared gut bacteria and immune molecules in the blood of people with long COVID and chronic fatigue syndrome. They found that people with these conditions have unusual patterns of gut bacteria and different levels of immune signaling molecules compared to healthy controls. These differences suggest the immune system and gut health may play a role in why some people develop long-lasting fatigue after infection.

Immune System

E2 ModerateCohortPEM unclearCase-Control

People with Long Covid and ME/CFS Exhibit Similarly Impaired Balance and Physical Capacity: A Case-Case-Control Study.

Hayes, Lawrence D, Sanal-Hayes, Nilihan E M, Mclaughlin, Marie et al.·The American journal of medicine·2025

This study compared balance and physical strength in people with long COVID, people with ME/CFS, and healthy volunteers. Both long COVID and ME/CFS patients showed significantly worse balance during standing and took longer to perform simple physical tasks like standing up from a chair compared to healthy people. Importantly, the balance and strength problems were equally severe in both groups, despite long COVID being a much newer illness.

E2 ModerateCohortPEM unclearCross-Sectional

Imbalanced Brain Neurochemicals in Long COVID and ME/CFS: A Preliminary Study Using MRI.

Thapaliya, Kiran, Marshall-Gradisnik, Sonya, Eaton-Fitch, Natalie et al.·The American journal of medicine·2025

Researchers used advanced brain imaging to measure chemical imbalances in ME/CFS and long COVID patients compared to healthy people. They found that two important brain chemicals—glutamate and N-acetyl-aspartate—were significantly higher in patients with both conditions. These chemical imbalances were connected to how severe patients' symptoms were, suggesting that abnormal brain chemistry may play a role in the exhaustion and other symptoms these patients experience.

Neuroinflammation

E2 ModerateDiagnosticPEM unclearMethods-Paper

Reliability and validity of the German version of the DePaul Symptom Questionnaire Post-Exertional Malaise (DSQ-PEM).

Kuczyk, Charlotte, Nöhre, Mariel, Herrmann-Lingen, Christoph et al.·Frontiers in psychiatry·2025

Researchers tested a German-language questionnaire designed to measure post-exertional malaise (PEM)—the worsening of symptoms that happens after physical or mental activity in ME/CFS and long COVID. They found the questionnaire is reliable and accurately distinguishes between people with and without long COVID, making it a useful tool for German-speaking patients and doctors.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Provocation of brachial plexus and systemic symptoms during the elevated arm stress test in individuals with myalgic encephalomyelitis/chronic fatigue syndrome or idiopathic chronic fatigue.

Edwards, Charles C, Byrnes, Julia M, Broussard, Camille A et al.·Journal of translational medicine·2025

Researchers tested whether a simple arm position exercise (holding arms overhead and opening/closing fists) could trigger symptoms in ME/CFS patients who struggle with overhead activities. They found that nearly all patients (97%) developed arm symptoms like pain, numbness, or heaviness during the test, and 41% also experienced whole-body symptoms like dizziness, brain fog, or a racing heart. This suggests that some ME/CFS patients may have nerve compression issues in their shoulders or neck that worsen with certain arm positions.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Awareness and Perception of Myalgic Encephalomyelitis and Chronic Fatigue Syndrome Among Pain Specialists: A Questionnaire-Based Study.

Uygun, Gürsan Güneş, Gözükızıl, Salim Taner, Bilen, Ayşegül·Cureus·2025

This study asked pain doctors in Turkey about their knowledge of ME/CFS and how they evaluate and treat patients with the condition. The results show that many pain specialists aren't familiar with ME/CFS, and some hold misconceptions—like thinking it's a type of depression or that intense exercise will help. This matters because pain doctors could potentially help ME/CFS patients, but they need better education about the condition first.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Depressive and anxiety symptoms in current, previous, and no history of ME/CFS: NHIS 2022 analysis.

Sirotiak, Zoe, Adamowicz, Jenna L, Thomas, Emily B K·Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation·2025

This study looked at anxiety and depression in people with ME/CFS using data from a large U.S. health survey. Researchers found that people currently living with ME/CFS reported much higher rates of anxiety and depression compared to people without ME/CFS. Interestingly, people who previously had ME/CFS but have since recovered still reported higher anxiety and depression rates than those who never had the illness, though the rates were lower than for those with current ME/CFS.

E2 ModerateCohortPEM unclearObservational

Predisposing and Precipitating Factors in Epstein-Barr Virus-Caused Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Jason, Leonard A, Katz, Ben Z·Microorganisms·2025

This study followed college students before and after they got infectious mononucleosis (IM) caused by Epstein-Barr virus to understand why some people develop ME/CFS afterward while others recover. Researchers collected health information and blood samples from students at three time points: before they got sick, shortly after their IM diagnosis, and six months later. By studying these young people over time, the researchers identified certain factors present before and during the infection that seemed to predict who would develop ME/CFS rather than recover.

E2 ModerateCohortPEM not requiredCross-Sectional

Peripheral Levels of Selected Biomarkers in Patients with Post-Sarcoidosis Chronic Fatigue Syndrome.

Małujło-Balcerska, Elżbieta, Bączek, Karol, Górski, Witold et al.·Journal of inflammation research·2025

This study looked at 71 people with sarcoidosis (a disease that causes inflammation) to understand why some feel extremely tired even after their disease improves. Researchers measured inflammation markers in the blood and found that people with lingering fatigue had higher levels of a protein called IL-6 compared to those without fatigue. The findings suggest that low-grade inflammation may be keeping people fatigued even when their disease appears to be under control.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

Medication use and symptomology in North American women with myalgic encephalomyelitis/chronic fatigue syndrome.

Pochakom, Angela, MacNevin, Gillian, Madden, Robyn F et al.·Frontiers in medicine·2025

This study surveyed 135 women with ME/CFS in North America to understand what medications they use and how these relate to their symptoms and daily functioning. Most participants were taking an average of 3 medications for ME/CFS-related symptoms, with pain medications being the most common, followed by psychiatric and immune-related medications. Interestingly, the study found a U-shaped pattern: both people using very few medications and those using many medications reported lower physical functioning, while moderate medication use was associated with better functioning.

Interventions

E2 ModerateCohortPEM not requiredCross-Sectional

Post-COVID-19 Condition Risk Factors and Symptom Clusters and Associations With Return to Pre-COVID-19 Health-Results From a 2021 Multistate Survey.

Konkle, Stacey L, Magleby, Reed, Bonacci, Robert A et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·2025

This study looked at nearly 30% of people who had COVID-19 in 2020 and developed long-term symptoms afterward (post-COVID condition). Among those with ongoing symptoms, about 77% had not fully recovered to their pre-COVID health 2-15 months later. The researchers found that certain symptom patterns—especially fatigue similar to ME/CFS, upper respiratory problems, and digestive issues—were most strongly linked to prolonged recovery.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Characterization of Postural Orthostatic Tachycardia Syndrome in Long COVID: Self-reported Data From the LISTEN Study.

Al Mouslmani, Mohammad, Sawano, Mitsuaki, Arun, Adith S et al.·JACC. Advances·2025

This study looked at people with long COVID who also developed POTS (a condition where the heart rate spikes when standing up). Among nearly 600 long COVID patients, about 29% reported having POTS. People with both conditions reported significantly more symptoms—including dizziness, chest pain, extreme fatigue, difficulty exercising, and brain fog—and experienced worse overall health and quality of life compared to those with long COVID alone.

Autonomic Nervous SystemCognitive Impairment

E2 ModerateCohortPEM unclearCase-Control

SMPDL3B a novel biomarker and therapeutic target in myalgic encephalomyelitis.

Rostami-Afshari, Bita, Elremaly, Wesam, Franco, Anita et al.·Journal of translational medicine·2025

Researchers identified a protein called SMPDL3B that appears to be elevated in people with ME/CFS and linked to symptom severity. This protein is found in the blood at higher levels in ME patients, particularly in women, and seems to be influenced by hormones and immune system dysfunction. The study also tested two existing diabetes medications (vildagliptin and saxagliptin) in the laboratory and found they could potentially help restore balance to this protein, suggesting a possible new treatment approach.

BiomarkersImmune System

E2 ModerateCohortPEM not requiredCross-Sectional

Assessment of the Gut Microbiome in Patients with Coexisting Irritable Bowel Syndrome and Chronic Fatigue Syndrome.

Chojnacki, Marcin, Błońska, Aleksandra, Kaczka, Aleksandra et al.·Nutrients·2025

This study looked at the gut bacteria and their byproducts in 80 women, comparing those with IBS alone to those with both IBS and chronic fatigue. Women with both conditions had different types of bacteria and different levels of certain chemicals in their urine, particularly those related to tryptophan (an amino acid). Higher levels of some of these chemicals were linked to worse fatigue symptoms.

Gut Microbiome

E2 ModerateCohortPEM unclearCross-Sectional

Circulating cell-free RNA signatures for the characterization and diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome.

Gardella, Anne E, Eweis-LaBolle, Daniel, Loy, Conor J et al.·Proceedings of the National Academy of Sciences of the United States of America·2025

Researchers analyzed tiny pieces of RNA floating in the blood of people with ME/CFS and compared them to healthy people. They used a computer program to identify a pattern of these RNA pieces that could help diagnose ME/CFS with 77% accuracy. The study found that people with ME/CFS have different levels of immune cells releasing material into their blood, suggesting the immune system is behaving differently.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Autonomic symptom burden, comorbidities and quality of life in women with Hypermobility Spectrum Disorders and hypermobile Ehlers-Danlos syndrome.

Collins Hutchinson, Meagan L, Liang, Emily, Fuster, Emily et al.·Autonomic neuroscience : basic & clinical·2025

This study looked at 84 women with connective tissue disorders (HSD/h-EDS) to understand how much autonomic nervous system problems they experience and how these affect their quality of life. The researchers found that these women had severe autonomic symptoms, with nearly 60% also having POTS and about 26% having ME/CFS. Overall, their quality of life was significantly worse than patients with other serious conditions like multiple sclerosis or rheumatoid arthritis.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Deep sequencing of BCR heavy chain repertoires in myalgic encephalomyelitis/chronic fatigue syndrome.

Ryback, Audrey A, Cowan, Graeme J M·Frontiers in immunology·2025

This study examined immune system cells called B cells in people with ME/CFS to see if the disease might be caused by chronic infections or autoimmune problems. Researchers compared blood samples from 25 patients with mild/moderate ME/CFS, 36 with severe ME/CFS, healthy people, and people with multiple sclerosis. They found that ME/CFS patients' B cells did not show the typical patterns expected if chronic infection or autoimmunity were the main cause, though they did notice a difference in the balance of certain antibody types in milder cases.

Severe MEImmune System

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Evidence Atlas

Evidence browser

Multiple voxel pattern analysis shows associations between chronic fatigue syndrome and cortical atrophy.

Alterations in gut microbiota and associated metabolites in patients with chronic fatigue syndrome.

Association between pre-existing chronic conditions and severity of first SARS-CoV-2 infection symptoms among adults living in Canada: a population-based survey analysis from January 2020 to August 2022.

Immune Signatures in Post-Acute Sequelae of COVID-19 (PASC) and Myalgia/Chronic Fatigue Syndrome (ME/CFS): Insights from the Fecal Microbiome and Serum Cytokine Profiles.

People with Long Covid and ME/CFS Exhibit Similarly Impaired Balance and Physical Capacity: A Case-Case-Control Study.

Imbalanced Brain Neurochemicals in Long COVID and ME/CFS: A Preliminary Study Using MRI.

Reliability and validity of the German version of the DePaul Symptom Questionnaire Post-Exertional Malaise (DSQ-PEM).

Provocation of brachial plexus and systemic symptoms during the elevated arm stress test in individuals with myalgic encephalomyelitis/chronic fatigue syndrome or idiopathic chronic fatigue.

Awareness and Perception of Myalgic Encephalomyelitis and Chronic Fatigue Syndrome Among Pain Specialists: A Questionnaire-Based Study.

Depressive and anxiety symptoms in current, previous, and no history of ME/CFS: NHIS 2022 analysis.

Predisposing and Precipitating Factors in Epstein-Barr Virus-Caused Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Peripheral Levels of Selected Biomarkers in Patients with Post-Sarcoidosis Chronic Fatigue Syndrome.

Medication use and symptomology in North American women with myalgic encephalomyelitis/chronic fatigue syndrome.

Post-COVID-19 Condition Risk Factors and Symptom Clusters and Associations With Return to Pre-COVID-19 Health-Results From a 2021 Multistate Survey.

Characterization of Postural Orthostatic Tachycardia Syndrome in Long COVID: Self-reported Data From the LISTEN Study.

SMPDL3B a novel biomarker and therapeutic target in myalgic encephalomyelitis.

Assessment of the Gut Microbiome in Patients with Coexisting Irritable Bowel Syndrome and Chronic Fatigue Syndrome.

Circulating cell-free RNA signatures for the characterization and diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome.

Autonomic symptom burden, comorbidities and quality of life in women with Hypermobility Spectrum Disorders and hypermobile Ehlers-Danlos syndrome.

Deep sequencing of BCR heavy chain repertoires in myalgic encephalomyelitis/chronic fatigue syndrome.

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Neuroinflammation Evidence

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