ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

61–80 of 2,768 studies

E2 ModerateCohortPEM unclearLongitudinal

Chronic Reactivation of Persistent Human Herpesviruses EBV, HHV-6 and VZV and Heightened Anti-dUTPase IgG Antibodies Are a Recurrent Hallmark in Post-Infectious ME/CFS and is Associated With Fatigue.

Palomo, Irene Mena, Cox, Brandon, Williams, Marshall V et al.·Journal of medical virology·2026

This study found that people with ME/CFS have higher levels of immune responses to three common viruses (EBV, HHV-6, and VZV) compared to healthy people. About 72% of ME/CFS patients showed antibodies to multiple viruses at the same time, versus only 31% of healthy controls. The antibody levels were higher in patients with moderate to severe fatigue, suggesting a possible connection between these viral reactivations and symptom severity.

BiomarkersImmune System

E2 ModerateCohortPEM unclearLongitudinal

Validation of the Wood Mental Fatigue Inventory in adolescents with myalgic encephalomyelitis/chronic fatigue syndrome.

Welch, David C, Edwards, Charles C, Broussard, Camille A et al.·Brain, behavior, & immunity - health·2026

This study tested whether a questionnaire called the Wood Mental Fatigue Inventory (WMFI) works well for measuring brain fog and cognitive problems in teenagers with ME/CFS. Researchers compared it to another commonly used teen fatigue scale and found that both questionnaires measured mental fatigue similarly and could track changes over time as teenagers received treatment.

Cognitive Impairment

E2 ModerateCohortPEM requiredObservational

Assessment and Incidence Determination of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Following a SARS-CoV-2 Infection in a Prospective Cohort of Hospital Employees.

Tack, Matthias, Gruber, Rosalie, Betting, Leia et al.·Medicina (Kaunas, Lithuania)·2026

This study followed hospital workers who got COVID-19 to see how many developed long-lasting fatigue and ME/CFS. About 12% still had fatigue months later, and 3% met the criteria for ME/CFS. Researchers found that people with these conditions often had signs of viral reactivation, immune system changes, and blood clotting abnormalities.

Post-Exertional Malaise

E2 ModerateBehavioralPEM not requiredObservational

The role of rehabilitation in Post-COVID-19 syndrome (PCS) recovery: An effectiveness study.

Collins, Gillian, Daly, Emma, Gallagher, David et al.·The British journal of occupational therapy·2026

This study tested whether a 6-week online rehabilitation program helped people recovering from long COVID. Thirty-six participants were tracked over 12 weeks—first during a waiting period where nothing changed, then during the rehabilitation program. The program, led by occupational therapists and physical therapists, taught practical strategies and provided peer support. Participants showed significant improvements in fatigue and symptom severity after completing the program.

E2 ModerateCohortPEM not required

Two neurocognitive domains identified for patients with myalgic encephalomyelitis/chronic fatigue syndrome and post-acute sequelae of COVID-19.

Sandoval, Ariadna, Li, Mingqi, Jason, Leonard A·Frontiers in neurology·2025

This study looked at brain-related symptoms in over 2,600 people with ME/CFS and COVID long-haul (PASC), finding that their cognitive problems fall into two main categories. The first group includes classic memory and concentration difficulties, while the second group involves being overwhelmed by sensory input like loud noises or bright lights. The research suggests that doctors and researchers should pay more attention to sensory overload as an important part of cognitive problems in these conditions.

Cognitive Impairment

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

Prevalence and severity of neurologic symptoms in Long-COVID and the role of pre-existing conditions, hospitalization, and mental health.

Huff, Hanalise V, Roberts, Henry, Bartrum, Elizabeth et al.·Frontiers in neurology·2025

This study looked at neurological symptoms in 213 people with Long-COVID, examined 8 months after infection. Researchers found that fatigue, brain fog, unrefreshed sleep, and word-finding difficulties were very common and often severe. Importantly, these symptoms appeared to be caused by the virus itself rather than by pre-existing health conditions or how sick people were during acute infection.

Cognitive Impairment

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 requiredObservational

Low-dose rapamycin alleviates clinical symptoms of fatigue and PEM in ME/CFS patients via improvement of autophagy: a pilot study.

Ruan, Brian T, Bulbule, Sarojini, Gile, Brooke et al.·Journal of translational medicine·2025

Researchers tested a low-dose drug called rapamycin in 86 ME/CFS patients to see if it could reduce fatigue and post-exertional malaise (PEM). About 74% of patients who completed the first month showed improvements in fatigue, PEM, and other symptoms, and the drug appeared safe with no serious side effects. The study suggests that rapamycin may work by fixing a cellular process called autophagy, which appears to be broken in ME/CFS patients.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

The Diagnostic Journey of Dysautonomia Patients: Insights from a Patient-Reported Outcome Study.

O'Dell, John A, Walker, Ash, Latham, Andrew J et al.·Journal of patient experience·2025

This study followed 672 adults with dysautonomia (a condition where the nervous system that controls automatic body functions doesn't work properly) to understand how long it takes to get diagnosed and which doctors help with diagnosis. On average, it took 7.7 years for people to receive a diagnosis, and they often saw multiple types of doctors before getting answers. The study found that dysautonomia commonly occurs alongside other conditions like Ehlers-Danlos syndrome, mast cell disorders, and ME/CFS, which can make diagnosis even more confusing.

Autonomic Nervous SystemDiagnostics

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 unclearCross-Sectional

An In-Depth Exploration of the Autoantibody Immune Profile in ME/CFS Using Novel Antigen Profiling Techniques.

Germain, Arnaud, Jaycox, Jillian R, Emig, Christopher J et al.·International journal of molecular sciences·2025

This study looked for specific immune proteins called autoantibodies in the blood of ME/CFS patients to see if they might be causing the illness. Researchers tested over 7,500 different immune markers using advanced laboratory techniques in 172 people. Surprisingly, they did not find significant differences in autoantibodies between ME/CFS patients and healthy controls, though they did notice some subtle patterns between men and women with ME/CFS that warrant further investigation.

Immune System

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 not requiredCross-Sectional

Chronic fatigue syndrome, depression, and anxiety symptoms due to relapsing-remitting multiple sclerosis are associated with reactivation of Epstein-Barr virus and Human Herpesvirus 6.

Maes, Michael, Almulla, Abbas F, Vojdani, Elroy et al.·Neuro endocrinology letters·2025

This study looked at whether reactivation of two common viruses—Epstein-Barr virus (EBV) and Human herpesvirus 6 (HHV-6)—are connected to fatigue, depression, and anxiety in people with a type of multiple sclerosis called RRMS. Researchers measured immune responses (antibodies) to these viruses in MS patients and healthy controls, and found that higher antibody levels were strongly linked to worse fatigue and mood symptoms. The findings suggest that when these dormant viruses become active in the body, they may trigger or worsen fatigue and psychiatric symptoms.

Immune System

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

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 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

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 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 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

← Previous Next 20 studies →

Or browse by topic

PEM Immune Neuro Metabolic Biomarkers Severe ME Long COVID Cognitive

Evidence Atlas

Evidence browser

Chronic Reactivation of Persistent Human Herpesviruses EBV, HHV-6 and VZV and Heightened Anti-dUTPase IgG Antibodies Are a Recurrent Hallmark in Post-Infectious ME/CFS and is Associated With Fatigue.

Validation of the Wood Mental Fatigue Inventory in adolescents with myalgic encephalomyelitis/chronic fatigue syndrome.

Assessment and Incidence Determination of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Following a SARS-CoV-2 Infection in a Prospective Cohort of Hospital Employees.

The role of rehabilitation in Post-COVID-19 syndrome (PCS) recovery: An effectiveness study.

Two neurocognitive domains identified for patients with myalgic encephalomyelitis/chronic fatigue syndrome and post-acute sequelae of COVID-19.

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

Prevalence and severity of neurologic symptoms in Long-COVID and the role of pre-existing conditions, hospitalization, and mental health.

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

Low-dose rapamycin alleviates clinical symptoms of fatigue and PEM in ME/CFS patients via improvement of autophagy: a pilot study.

The Diagnostic Journey of Dysautonomia Patients: Insights from a Patient-Reported Outcome Study.

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

An In-Depth Exploration of the Autoantibody Immune Profile in ME/CFS Using Novel Antigen Profiling Techniques.

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

Chronic fatigue syndrome, depression, and anxiety symptoms due to relapsing-remitting multiple sclerosis are associated with reactivation of Epstein-Barr virus and Human Herpesvirus 6.

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.

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.

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

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

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

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

Curated Collections

Neuroinflammation Evidence

Metabolism & Mitochondria

Biomarkers

PEM-Specific Research