ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

181–200 of 2,768 studies

E2 ModerateCohortPEM unclearObservational

Autonomic Dysfunction in Patients with Acute Infection with Coxiella burnetii.

Milovanović, Branislav, Marković, Nikola, Ristanović, Elizabeta et al.·Pathogens (Basel, Switzerland)·2025

This study looked at how the autonomic nervous system (the part that controls heart rate, blood pressure, and other automatic body functions) works in people who had acute infection with Coxiella burnetii, a bacterium that causes Q fever. Researchers tested 100 infected patients and 56 healthy controls using heart monitoring tests and found that infected patients had more problems with autonomic control, particularly in how their bodies regulate heart rate and blood pressure. These findings suggest that this infection might trigger lasting problems with the autonomic nervous system that could contribute to ME/CFS symptoms.

Autonomic Nervous System

E2 ModerateCohortPEM requiredCase-Control

Haptoglobin phenotypes and structural variants associate with post-exertional malaise and cognitive dysfunction in myalgic encephalomyelitis.

Moezzi, Atefeh, Ushenkina, Anastasiya, Widgren, Anna et al.·Journal of translational medicine·2025

Researchers studied a protein called haptoglobin in people with ME/CFS and found it may be connected to post-exertional malaise (that worsening of symptoms after activity) and brain fog. They discovered that certain genetic variations of this protein were more common in ME/CFS patients, and those variations were linked to worse symptoms and cognitive problems. The study suggests haptoglobin could be a useful marker to help doctors understand why ME/CFS symptoms vary between patients.

BiomarkersPost-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Genetic variants associated with chronic fatigue syndrome predict population-level fatigue severity and actigraphic measurements.

Liu, Patrick Z, Raizen, David M, Skarke, Carsten et al.·Sleep·2025

This study looked at whether the genetic factors that cause ME/CFS also influence fatigue levels in people without ME/CFS. Researchers compared movement patterns and body temperature rhythms in people with ME/CFS versus healthy controls, then checked if genetic variations linked to ME/CFS were also connected to fatigue in the general population. They found that people with ME/CFS showed significantly less movement and flatter daily temperature patterns, and some genetic variants associated with ME/CFS were also linked to fatigue symptoms in the broader population.

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 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 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 unclearLongitudinal

Functional olfactory impairment and fatigue in post-COVID-19 syndrome including ME/CFS - a longitudinal prospective observational study.

Meyer-Arndt, Lil, Pierchalla, Greta, Mödl, Lukas et al.·Brain, behavior, & immunity - health·2025

This study followed 45 long-COVID patients over 28 months to understand the connection between smell problems and fatigue, including those who developed ME/CFS. Researchers tested how well patients could smell (detecting scent strength, telling scents apart, and identifying them) and measured their fatigue, thinking ability, and physical strength. Most patients' smell improved over time, but problems with identifying specific smells lasted the longest, and patients with better smell discrimination at the start tended to feel better and function better after 20 months.

Cognitive Impairment

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 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

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 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 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

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 unclearCross-Sectional

Abnormal T-Cell activation and cytotoxic T-Cell frequency discriminate symptom severity in myalgic encephalomyelitis/chronic fatigue syndrome.

Lee, Ji-Sook, Lacerda, Eliana, Kingdon, Caroline et al.·Journal of translational medicine·2025

This study compared immune system profiles in 96 ME/CFS patients with either mild/moderate or severe disease. Researchers found that people with severe ME/CFS had more activated immune cells and higher levels of inflammatory chemicals, while those with milder disease showed different patterns suggesting their bodies were responding to chronic viral infection. These findings suggest that mild and severe ME/CFS may involve different underlying immune problems, which could eventually help doctors predict disease severity and develop targeted treatments.

Immune System

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 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

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 not requiredCross-Sectional

Deep learning analysis of long COVID and vaccine impact in low- and middle-income countries (LMICs): development of a risk calculator in a multicentric study.

Shaheen, Ahmed, Shaheen, Nour, Long COVID Collaboration Study Group in the LMICs et al.·Frontiers in public health·2025

Researchers studied over 2,400 COVID-19 patients in low- and middle-income countries to understand why some people develop long-lasting symptoms like chronic fatigue and depression after infection. They used advanced computer analysis to identify which patients were at highest risk for these prolonged symptoms. The study found that vaccination reduced the risk of developing these long-term problems, and that older age, being female, and smoking were linked to higher risk of chronic fatigue.

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

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Autonomic Dysfunction in Patients with Acute Infection with Coxiella burnetii.

Haptoglobin phenotypes and structural variants associate with post-exertional malaise and cognitive dysfunction in myalgic encephalomyelitis.

Genetic variants associated with chronic fatigue syndrome predict population-level fatigue severity and actigraphic measurements.

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.

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.

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

Functional olfactory impairment and fatigue in post-COVID-19 syndrome including ME/CFS - a longitudinal prospective observational study.

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.

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

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

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

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

Abnormal T-Cell activation and cytotoxic T-Cell frequency discriminate symptom severity in myalgic encephalomyelitis/chronic fatigue syndrome.

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

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

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

Deep learning analysis of long COVID and vaccine impact in low- and middle-income countries (LMICs): development of a risk calculator in a multicentric study.

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

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