ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

101–120 of 2,768 studies

E2 ModerateBehavioralPEM not requiredObservational

Welfare benefit utilization for people with functional somatic disorder. A population-based cohort study.

Petersen, Marie Weinreich, Wellnitz, Kaare Bro, Carstensen, Tina Birgitte Wisbech et al.·Journal of psychosomatic research·2025

This study looked at how many weeks per year people with functional somatic disorder (FSD)—a condition with persistent physical symptoms that can't be explained by standard medical tests—used welfare benefits compared to people without FSD. Researchers in Denmark tracked about 9,600 people over 14 years and found that people with FSD used significantly more sickness benefits, unemployment benefits, and disability pensions than those without the condition. The findings show that FSD is a seriously disabling condition that affects people's ability to work and support themselves.

E2 ModerateCohortPEM unclearRegistry-Resource

Unequal access to diagnosis of myalgic encephalomyelitis in England.

Samms, Gemma Louise, Ponting, Chris P·BMC public health·2025

This study examined NHS records from England to understand how many people have ME/CFS and whether diagnosis is fair across different groups. Researchers found that about 100,000 people in England have been officially diagnosed with ME/CFS, but the actual number may be much higher—around 404,000 in the UK. The diagnosis rates varied significantly depending on gender, age, ethnicity, and where people live, suggesting some patients are being missed.

Diagnostics

E2 ModerateCohortPEM unclearObservational

Absence of BOLD adaptation in chronic fatigue syndrome revealed by task functional MRI.

Schönberg, Laura, Mohamed, Abdalla Z, Yu, Qiang et al.·Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism·2025

This study looked at how the brain responds when people with ME/CFS do mental tasks, using brain imaging to measure blood flow. Researchers found that while healthy people's brains become more efficient with repeated effort (showing less activation over time), people with ME/CFS showed the opposite pattern—their brains actually increased activity with each repetition. This suggests that ME/CFS may involve a fundamental difference in how the brain adapts to mental work, potentially explaining why cognitive tasks feel so exhausting.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic overlapping pain conditions in individuals with active opioid use disorder: a descriptive study of syringe program participants.

Rausch, Johnathan, Harte, Steven E, Williams, David A et al.·Journal of addictive diseases·2025

This study looked at how often chronic pain conditions occur together in people struggling with opioid addiction. Researchers found that people with opioid use disorder have much higher rates of several overlapping pain conditions—including ME/CFS, fibromyalgia, chronic migraines, and chronic back pain—than would be expected in the general population. Understanding this connection may help doctors treat both the pain and addiction more effectively.

E2 ModerateCohortPEM unclearCross-Sectional

Leveraging Explainable Automated Machine Learning (AutoML) and Metabolomics for Robust Diagnosis and Pathophysiological Insights in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

Yagin, Fatma Hilal, Colak, Cemil, Al-Hashem, Fahaid et al.·Diagnostics (Basel, Switzerland)·2025

Researchers used advanced computer learning and blood tests to find chemical markers that could help diagnose ME/CFS. They analyzed 888 different chemicals in blood samples from 106 ME/CFS patients and 91 healthy people, and found a pattern of chemical imbalances that correctly identified ME/CFS patients 87% of the time. The key chemical imbalances involved energy production in cells, inflammation, and gut health—areas that have long been suspected in ME/CFS.

Energy Metabolism

E2 ModerateCohortPEM not requiredObservational

Nonpelvic comorbid symptoms of 45 patients with pain of pelvic venous origin, before and after treatment.

Smith, Steven J, Smith, B Holly, Sichlau, Michael J et al.·Phlebology·2025

This study looked at 45 women with chronic pelvic pain caused by abnormal blood pooling in pelvic veins. These patients experienced many symptoms beyond pelvic pain—including brain fog, fatigue, migraines, constipation, and anxiety. After receiving a catheter-based procedure to fix the blood pooling, most of these systemic symptoms improved significantly (by 50% or more).

Pain and SensitizationAutonomic Nervous SystemCognitive Impairment

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

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 requiredObservational

The Clinical Relevance of Mast Cell Activation in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Rohrhofer, Johanna, Ebner, Lilian, Schweighardt, Johannes et al.·Diagnostics (Basel, Switzerland)·2025

This study looked at whether mast cells—immune cells that release chemicals causing inflammation—play a role in ME/CFS. Researchers surveyed 687 ME/CFS patients and reviewed records from 383 others, finding that about 25% had signs of problematic mast cell activation. Importantly, patients with mast cell problems who received targeted treatment reported better symptom relief than those without mast cell involvement, suggesting this might be a treatable subtype of ME/CFS.

Immune SystemPost-Exertional Malaise

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

E2 ModerateCohortPEM requiredCross-Sectional

Concentrations of uremic bacterial metabolites in patients with post-COVID-19 syndrome.

Brigo, Natascha, Mayr, Wolfram, Taenzer, Maja et al.·Frontiers in cellular and infection microbiology·2025

This small study looked at special waste products made by gut bacteria in the urine of people with long COVID, ME/CFS, and healthy people. Researchers found that people with long COVID and ME/CFS had different patterns of these bacterial products compared to healthy controls, and these patterns might be connected to their symptoms like fatigue and post-exertional malaise (feeling much worse after activity).

Post-Exertional Malaise

E2 ModerateDiagnosticPEM unclearCross-Sectional

Psychometric evaluation of the PROMIS® physical function short form 12a for use by adults with myalgic encephalomyelitis/chronic fatigue syndrome.

Yang, Manshu, Keller, San, Rafiee, Parisa et al.·Health and quality of life outcomes·2025

Researchers tested whether a questionnaire called PROMIS Physical Function Short Form (PF-SF) works well for measuring how much ME/CFS affects a person's ability to do physical activities. They asked 173 people with ME/CFS and 161 healthy people to complete the questionnaire and found that it accurately captured the differences in physical ability between the two groups. The questionnaire appears to be a reliable and useful tool for doctors and researchers to measure physical function in people with ME/CFS.

E2 ModerateCohortPEM unclearCross-Sectional

Circulating FGF-21 as a Disease-Modifying Factor Associated with Distinct Symptoms and Cognitive Profiles in Myalgic Encephalomyelitis and Fibromyalgia.

Azimi, Ghazaleh, Elremaly, Wesam, Elbakry, Mohamed et al.·International journal of molecular sciences·2025

This study measured a protein called FGF-21 in the blood of people with ME/CFS, fibromyalgia, and both conditions combined, then compared how their symptoms and thinking abilities differed based on their FGF-21 levels. The researchers found that FGF-21 levels—not just the diagnosis alone—were better at predicting which symptoms and cognitive problems each person would experience. This suggests FGF-21 could become a useful blood test to help doctors understand and treat these conditions more precisely.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Impact of the COVID-19 Pandemic and the 2021 National Institute for Health and Care Excellence Guidelines on Public Perspectives Toward Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Thematic and Sentiment Analysis on Twitter (Rebranded as X).

Khakban, Iliya, Jain, Shagun, Gallab, Joseph et al.·Journal of medical Internet research·2025

Researchers analyzed nearly 900,000 posts about ME/CFS on Twitter from 2010 to 2024 to understand what patients and the public were discussing about the illness. They found that most posts were neutral (47%), but negative posts increased over time, especially after the COVID-19 pandemic and when new UK treatment guidelines were published in 2021. Patients frequently expressed frustration about ME/CFS being dismissed as a mental health condition and celebrated the 2021 guidelines that recognized it as a physical disease.

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 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 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 not requiredCross-Sectional

Abnormal breathing patterns and hyperventilation are common in patients with chronic fatigue syndrome during exercise.

Mancini, Donna M, Brunjes, Danielle L, Cook, Dane et al.·Frontiers in medicine·2025

Researchers studied how patients with ME/CFS breathe during exercise and found that many breathe abnormally in ways that healthy people do not. Specifically, 42% of ME/CFS patients showed irregular breathing patterns, and 32% were breathing too fast and too deeply (hyperventilation). These breathing problems were much more common in ME/CFS patients than in the healthy control group, suggesting that abnormal breathing may be contributing to the fatigue and breathlessness patients experience.

Post-Exertional Malaise

E2 ModerateBehavioralPEM unclearCase-Control

Bipolar spectrum, hypothyroidism, and their association with chronic fatigue/myalgic encephalomyelitis-like syndrome in long COVID: could they be identified as early determinants?

Tusconi, Massimo, Dursun, Serdar M, Pegreffi, Francesco et al.·Frontiers in psychiatry·2025

This study found that people with long COVID who developed ME/CFS-like symptoms were much more likely to have had hypothyroidism (an underactive thyroid) or bipolar spectrum disorders before getting sick compared to people from before the pandemic. The researchers suggest these pre-existing conditions might make someone more vulnerable to developing ME/CFS after COVID-19, possibly because they affect sleep rhythms and immune function.

E2 ModerateCohortPEM unclearCross-Sectional

A Cross-Sectional Study of Symptom Prevalence, Frequency, Severity, and Impact of Long COVID in Scotland: Part I.

Mclaughlin, Marie, Cerexhe, Luke, Macdonald, Eilidh et al.·The American journal of medicine·2025

Researchers surveyed 253 people living with long COVID in Scotland to understand which symptoms are most common and how severe they are. The most frequent symptoms were post-exertional malaise (when activity makes symptoms worse), extreme tiredness, and thinking problems. The study found that people living in areas with more deprivation experienced more symptoms, but factors like vaccination status and age did not significantly affect symptom patterns.

Post-Exertional Malaise

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Evidence Atlas

Evidence browser

Welfare benefit utilization for people with functional somatic disorder. A population-based cohort study.

Unequal access to diagnosis of myalgic encephalomyelitis in England.

Absence of BOLD adaptation in chronic fatigue syndrome revealed by task functional MRI.

Chronic overlapping pain conditions in individuals with active opioid use disorder: a descriptive study of syringe program participants.

Leveraging Explainable Automated Machine Learning (AutoML) and Metabolomics for Robust Diagnosis and Pathophysiological Insights in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

Nonpelvic comorbid symptoms of 45 patients with pain of pelvic venous origin, before and after treatment.

Circulating cell-free RNA signatures for the characterization and diagnosis of 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.

The Clinical Relevance of Mast Cell Activation in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

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

Concentrations of uremic bacterial metabolites in patients with post-COVID-19 syndrome.

Psychometric evaluation of the PROMIS® physical function short form 12a for use by adults with myalgic encephalomyelitis/chronic fatigue syndrome.

Circulating FGF-21 as a Disease-Modifying Factor Associated with Distinct Symptoms and Cognitive Profiles in Myalgic Encephalomyelitis and Fibromyalgia.

Impact of the COVID-19 Pandemic and the 2021 National Institute for Health and Care Excellence Guidelines on Public Perspectives Toward Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Thematic and Sentiment Analysis on Twitter (Rebranded as X).

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

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

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.

Abnormal breathing patterns and hyperventilation are common in patients with chronic fatigue syndrome during exercise.

Bipolar spectrum, hypothyroidism, and their association with chronic fatigue/myalgic encephalomyelitis-like syndrome in long COVID: could they be identified as early determinants?

A Cross-Sectional Study of Symptom Prevalence, Frequency, Severity, and Impact of Long COVID in Scotland: Part I.

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