ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2807 studies

201–220 of 2,807 studies

E2 ModerateBehavioralPEM not requiredLongitudinal

Risk factors for fatigue severity in the post-COVID-19 condition: A prospective controlled cohort study of nonhospitalised adolescents and young adults.

Selvakumar, Joel, Havdal, Lise Beier, Brodwall, Elias Myrstad et al.·Brain, behavior, & immunity - health·2025

This study followed young people (ages 12–25) who had COVID-19 to understand why some develop long-lasting fatigue while others recover well. Researchers found that how severe symptoms were in the first few weeks after infection—and psychological factors like loneliness and worry—were much stronger predictors of ongoing fatigue at 6 months than any blood test or physical measure. Surprisingly, whether someone actually had COVID-19 made only a small difference; other life circumstances and emotional stress mattered more.

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 requiredLongitudinal

Incidence and Prevalence of Post-COVID-19 Myalgic Encephalomyelitis: A Report from the Observational RECOVER-Adult Study.

Vernon, Suzanne D, Zheng, Tianyu, Do, Hyungrok et al.·Journal of general internal medicine·2025

This study tracked over 11,000 people who had COVID-19 and about 1,400 who didn't, following them for at least 6 months to see how many developed ME/CFS. Researchers found that people who had COVID-19 were nearly 5 times more likely to develop ME/CFS compared to people who never had COVID-19. About 4.5% of COVID-infected participants developed ME/CFS, compared to only 0.6% of uninfected people.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearObservational

A comparison of genome-wide association analyses of persistent symptoms after Lyme disease, fibromyalgia, and myalgic encephalomyelitis - chronic fatigue syndrome.

Hirsch, Annemarie G, Justice, Anne E, Poissant, Amy et al.·BMC infectious diseases·2025

Researchers studied the genes of people who had Lyme disease to understand why some develop lasting symptoms even after treatment. They found two genetic regions that might be involved in persistent Lyme disease symptoms, with one linked to a protein called MARC2 that affects immune function. When they checked whether these same genetic changes appeared in people with fibromyalgia or ME/CFS, they did not find the same patterns, suggesting these conditions may have different genetic roots.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

Mapping the complexity of ME/CFS: Evidence for abnormal energy metabolism, altered immune profile, and vascular dysfunction.

Heng, Benjamin, Gunasegaran, Bavani, Krishnamurthy, Shivani et al.·Cell reports. Medicine·2025

This study examined blood samples from ME/CFS patients and healthy people to understand what goes wrong in the body. Researchers found that immune cells in ME/CFS patients are struggling to make energy (ATP), the fuel that powers our cells. The immune system also showed signs of being immature or worn out, and blood proteins related to clotting and blood vessel problems were elevated, suggesting blood vessel dysfunction may contribute to ME/CFS symptoms.

BiomarkersImmune System

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 ModerateCohortPEM requiredCross-Sectional

Examining Well-Being and Cognitive Function in People With Long COVID and ME/CFS, and Age-Matched Healthy Controls: A Case-Case-Control Study.

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

This study compared how people with long COVID and ME/CFS experience their daily well-being and thinking abilities, compared to healthy people of similar ages. Researchers found that both long COVID and ME/CFS patients reported similar struggles with fatigue, pain, sleep problems, anxiety, and difficulty with everyday activities—but their actual test performance on thinking tasks was comparable to healthy controls. The findings suggest that both conditions affect quality of life in very similar ways.

Post-Exertional Malaise

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

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 requiredCase-Control

Development and validation of blood-based diagnostic biomarkers for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) using EpiSwitch® 3-dimensional genomic regulatory immuno-genetic profiling.

Hunter, Ewan, Alshaker, Heba, Bundock, Oliver et al.·Journal of translational medicine·2025

Researchers developed a new blood test called EpiSwitch®CFS that may help diagnose ME/CFS by detecting specific patterns in how DNA is organized in blood cells. When tested on stored blood samples from 47 ME/CFS patients and 61 healthy people, the test correctly identified 92% of ME/CFS patients and correctly ruled out 98% of healthy controls. This could potentially help doctors diagnose ME/CFS more reliably, since there is currently no standard blood test for the condition.

NeuroinflammationBiomarkersImmune System

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 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 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 requiredLongitudinal

Decreased risk of chronic fatigue syndrome following influenza vaccine: a 20-year population-based retrospective study.

Chang, Hsun, Yao, Wei-Cheng, Yu, Teng-Shun et al.·Journal of translational medicine·2025

This study looked at whether getting the flu increases the risk of developing ME/CFS. Researchers tracked nearly 310,000 people who had the flu and compared them to a similar group who did not get the flu over 12 years. They found that people who had the flu were about 50% more likely to develop ME/CFS afterward, but people who received the flu vaccine had lower rates of developing ME/CFS.

E2 ModerateCohortPEM requiredCross-Sectional

Fatigue, interoplastic and nociplastic distress in myalgic encephalomyelitis/chronic fatigue syndrome, Gulf War Illness, and chronic idiopathic fatigue.

Chen, Emily, Rudder, Tamera, Nwankwere, Charles et al.·Frontiers in neuroscience·2025

This study compared pain sensitivity and fatigue in people with ME/CFS, Gulf War Illness, and chronic fatigue to understand what causes their symptoms. Researchers found that people with ME/CFS and Gulf War Illness have increased pain sensitivity (measured by pressing on their skin), and their pain and internal body sensations are closely linked. However, pain sensitivity didn't strongly correlate with fatigue levels, suggesting that fatigue may involve different mechanisms than pain.

Post-Exertional Malaise

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 requiredCross-Sectional

Understanding symptom clusters, diagnosis and healthcare experiences in myalgic encephalomyelitis/chronic fatigue syndrome and long COVID: a cross-sectional survey in the UK.

Mansoubi, Maedeh, Richards, Thomas, Ainsworth-Wells, Martine et al.·BMJ open·2025

This large UK survey asked over 8,800 people with ME/CFS or long COVID about their symptoms and experiences with healthcare. The study found that fatigue, brain fog, pain, and sleep problems are the most common symptoms, but people often wait years for a diagnosis. Even after new healthcare guidelines were introduced, most patients said they weren't satisfied with the care they received from the NHS.

Post-Exertional Malaise

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 unclearCross-Sectional

Autonomic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): Findings from the Multi-Site Clinical Assessment of ME/CFS (MCAM) Study in the USA.

Issa, Anindita, Lin, Jin-Mann S, Chen, Yang et al.·Journal of clinical medicine·2025

This study found that people with ME/CFS experience much higher levels of autonomic nervous system problems—which control things like heart rate, blood pressure, and digestion—compared to healthy people. Nearly all ME/CFS patients (97%) had at least one autonomic symptom, with common complaints including dizziness, cold hands and feet, and difficulty standing up. The more autonomic symptoms someone had, especially in certain areas like blood pressure regulation and stomach problems, the more severe their overall illness tended to be.

Autonomic Nervous System

E2 ModerateCohortPEM unclearObservational

Oral minocycline therapy as first-line treatment in patients with Myalgic encephalomyelitis and long COVID: A pilot study.

Miwa, Kunihisa·eNeurologicalSci·2025

This small study looked at whether a common antibiotic called minocycline might help people with ME/CFS, including those with long COVID. Fifty-five patients took minocycline for about 6 weeks, and 80% of those who completed the treatment reported meaningful improvements in their symptoms like fatigue, brain fog, and sleep problems. The treatment worked best for people early in their illness (within 6 months of symptom onset).

Post-Exertional Malaise

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Evidence browser

Risk factors for fatigue severity in the post-COVID-19 condition: A prospective controlled cohort study of nonhospitalised adolescents and young adults.

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

Incidence and Prevalence of Post-COVID-19 Myalgic Encephalomyelitis: A Report from the Observational RECOVER-Adult Study.

A comparison of genome-wide association analyses of persistent symptoms after Lyme disease, fibromyalgia, and myalgic encephalomyelitis - chronic fatigue syndrome.

Mapping the complexity of ME/CFS: Evidence for abnormal energy metabolism, altered immune profile, and vascular dysfunction.

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

Examining Well-Being and Cognitive Function in People With Long COVID and ME/CFS, and Age-Matched Healthy Controls: A Case-Case-Control Study.

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

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

Development and validation of blood-based diagnostic biomarkers for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) using EpiSwitch® 3-dimensional genomic regulatory immuno-genetic profiling.

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

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

SMPDL3B a novel biomarker and therapeutic target in myalgic encephalomyelitis.

Decreased risk of chronic fatigue syndrome following influenza vaccine: a 20-year population-based retrospective study.

Fatigue, interoplastic and nociplastic distress in myalgic encephalomyelitis/chronic fatigue syndrome, Gulf War Illness, and chronic idiopathic fatigue.

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

Understanding symptom clusters, diagnosis and healthcare experiences in myalgic encephalomyelitis/chronic fatigue syndrome and long COVID: a cross-sectional survey in the UK.

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

Autonomic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): Findings from the Multi-Site Clinical Assessment of ME/CFS (MCAM) Study in the USA.

Oral minocycline therapy as first-line treatment in patients with Myalgic encephalomyelitis and long COVID: A pilot study.

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