ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

481–500 of 2,768 studies

E2 ModerateCohortPEM unclearCase-Control

Orthostatic Intolerance in Long-Haul COVID after SARS-CoV-2: A Case-Control Comparison with Post-EBV and Insidious-Onset Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients.

van Campen, C Linda M C, Visser, Frans C·Healthcare (Basel, Switzerland)·2022

This study compared patients with long-haul COVID to two groups of ME/CFS patients (those who got sick after Epstein-Barr virus infection and those who became ill gradually) to understand a common symptom called orthostatic intolerance—dizziness or fainting when standing up. Researchers found that long-haul COVID patients had similar symptoms and physical responses to standing as ME/CFS patients, and all three groups showed comparable problems with blood flow and heart function during the standing test. The findings suggest that long-haul COVID and ME/CFS may be essentially the same underlying condition.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredLongitudinal

Subjective and objective cognitive function in adolescent with chronic fatigue following Epstein-Barr virus infection.

Øie, Merete Glenne, Rødø, Astrid Sofie Buer, Bølgen, Maria Sletten et al.·Journal of psychosomatic research·2022

This study followed 195 teenagers who had Epstein-Barr virus infection for six months to see if they developed persistent fatigue and cognitive problems. While teenagers with ongoing fatigue reported much more trouble with thinking and memory than healthy teenagers, standard cognitive tests showed no actual differences in their thinking abilities. This suggests that cognitive difficulties in ME/CFS may feel very real to patients but are not always detectable by traditional testing methods.

Cognitive Impairment

E2 ModerateCohortPEM requiredObservational

A 2-day cardiopulmonary exercise test in chronic fatigue syndrome patients who were exposed to humidifier disinfectants.

Leem, Jong-Han, Jeon, Hyoung-Eun, Nam, Hun et al.·Environmental analysis, health and toxicology·2022

This study tested whether a special two-day exercise test could detect post-exertional malaise (PEM)—the worsening of symptoms after physical activity—in people with ME/CFS who had been exposed to humidifier disinfectants. The researchers had 29 participants complete an exercise test, rest for 24 hours, then repeat it. They found that performance noticeably declined on the second day, showing that PEM is real and measurable.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

The Significance of Pain Drawing as a Screening Tool for Cervicogenic Headache and Associated Symptoms in Chronic Fatigue.

Bernhoff, Gabriella, Huhmar, Helena M, Rasmussen-Barr, Eva et al.·Journal of pain research·2022

This study looked at whether a simple drawing tool could help identify a specific type of headache (cervicogenic headache) in people with ME/CFS. Researchers found that 42% of ME/CFS patients had a particular pain pattern on their drawings that suggested their headache came from their neck. Patients with this neck-related pain pattern also experienced more dizziness, worse pain, and lower quality of life compared to others.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCross-Sectional

Intersections between pneumonia, lowered oxygen saturation percentage and immune activation mediate depression, anxiety, and chronic fatigue syndrome-like symptoms due to COVID-19: A nomothetic network approach.

Al-Jassas, Hawraa Kadhem, Al-Hakeim, Hussein Kadhem, Maes, Michael·Journal of affective disorders·2022

This study examined 60 COVID-19 patients and 30 healthy controls to understand why some people develop depression, anxiety, and fatigue-like symptoms after COVID-19 infection. The researchers found that lung damage (seen on CT scans), low oxygen levels, and an overactive immune response are connected to these mental health and fatigue symptoms. Essentially, the physical damage to the lungs may trigger immune system activation, which then leads to depression, anxiety, and fatigue.

Immune System

E2 ModerateCohortPEM requiredCross-Sectional

ME/CFS and Post-Exertional Malaise among Patients with Long COVID.

Jason, Leonard A, Dorri, Joseph A·Neurology international·2022

Researchers studied 465 people with long-term COVID symptoms to see how many also had ME/CFS (a serious condition causing extreme fatigue and worsening after activity). They found that about 6 in 10 people with long COVID met the medical criteria for ME/CFS. Interestingly, some people thought they had ME/CFS when they didn't, while others had ME/CFS without realizing it—showing that self-diagnosis alone isn't reliable.

Long COVID OverlapPost-Exertional Malaise

E2 ModerateBehavioralPEM not requiredCase-Control

Treatments of chronic fatigue syndrome and its debilitating comorbidities: a 12-year population-based study.

Leong, Kam-Hang, Yip, Hei-Tung, Kuo, Chien-Feng et al.·Journal of translational medicine·2022

This study looked at over 12,000 people in Taiwan with ME/CFS and compared them to an equal number of similar people without the condition. Researchers found that people with ME/CFS are much more likely to also have depression, anxiety, sleep problems, and certain other illnesses like diabetes and rheumatoid arthritis. The study also found that doctors commonly prescribed antidepressants, anti-anxiety medications, pain relievers, and recommended exercise and therapy—treatments that earlier research suggested might help with ME/CFS symptoms.

Interventions

E2 ModerateCohortPEM not requiredCross-Sectional

Small-Fiber Polyneuropathy Is Prevalent in Patients With Interstitial Cystitis/Bladder Pain Syndrome.

Wolff, Dylan T, Xu, Raymond, Overholt, Tyler et al.·Urogynecology (Philadelphia, Pa.)·2022

Researchers found that about one-third of people with bladder pain syndrome (IC/BPS) have small-fiber polyneuropathy (SFPN), a condition where tiny nerves in the skin are damaged or reduced. Notably, people with SFPN were significantly more likely to also have chronic fatigue syndrome (31% vs 10.6%). This suggests these two painful conditions may share a common nerve-related mechanism.

E2 ModerateCohortPEM unclearObservational

Predictors for Developing Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Following Infectious Mononucleosis.

Jason, Leonard A, Cotler, Joseph, Islam, Mohammed F et al.·Journal of rehabilitation therapy·2022

This study followed 238 college students who developed infectious mononucleosis to see who would recover and who would develop ME/CFS. Researchers found that students who had stomach problems (pain, bloating, irritable bowel) before getting sick, combined with certain low immune markers and severe digestive symptoms when they got mononucleosis, had about an 80% chance of developing severe ME/CFS that lasted six months. This suggests that pre-existing gut problems and immune differences may help predict who is at highest risk.

Immune System

E2 ModerateCohortPEM requiredCross-Sectional

Clinical Characteristics of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Diagnosed in Patients with Long COVID.

Tokumasu, Kazuki, Honda, Hiroyuki, Sunada, Naruhiko et al.·Medicina (Kaunas, Lithuania)·2022

This study examined patients with long COVID who developed ME/CFS, a serious condition causing extreme fatigue and worsening after activity. Researchers found that about 17% of long COVID patients met standardized medical criteria for ME/CFS, with fatigue and post-exertional malaise being the most common symptoms. Interestingly, men and women were affected equally in this group, which differs from typical ME/CFS patterns.

Post-Exertional Malaise

E2 ModerateCohortPEM not required

Metabolomic Evidence for Peroxisomal Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Che, Xiaoyu, Brydges, Christopher R, Yu, Yuanzhi et al.·International journal of molecular sciences·2022

Researchers found that people with ME/CFS have abnormal levels of certain fats and chemicals in their blood compared to healthy people. Specifically, they had lower levels of protective fats called plasmalogens and phospholipids, but higher levels of compounds called dicarboxylic acids. These chemical differences were so distinctive that a computer program could identify ME/CFS patients from their blood work with reasonable accuracy.

Biomarkers

E2 ModerateMechanismPEM requiredObservational

Plasma metabolomics reveals disrupted response and recovery following maximal exercise in myalgic encephalomyelitis/chronic fatigue syndrome.

Germain, Arnaud, Giloteaux, Ludovic, Moore, Geoffrey E et al.·JCI insight·2022

Researchers studied 60 ME/CFS patients and 45 healthy people by measuring thousands of chemical substances in their blood before and after intense exercise tests done 24 hours apart. They found that ME/CFS patients had very different chemical patterns in their blood, especially after exercise and during the 24-hour recovery period, suggesting their bodies struggle to respond to and recover from physical exertion in ways that may explain post-exertional malaise (the worsening of symptoms after activity).

Energy MetabolismPost-Exertional Malaise

E2 ModerateCohortPEM requiredProtocol

Multimodal MRI of myalgic encephalomyelitis/chronic fatigue syndrome: A cross-sectional neuroimaging study toward its neuropathophysiology and diagnosis.

Shan, Zack Y, Mohamed, Abdalla Z, Andersen, Thu et al.·Frontiers in neurology·2022

This study used advanced brain imaging to investigate whether ME/CFS is caused by a problem with how the brain's blood vessels respond to neural activity. Researchers scanned the brains of 288 people—including those with ME/CFS, chronic fatigue, fibromyalgia, and healthy controls—while they performed tasks and held their breath, measuring blood flow and brain chemicals. The goal was to find distinctive brain patterns that could objectively diagnose ME/CFS and understand what goes wrong in this disease.

Biomarkers

E2 ModerateCohortPEM not requiredLongitudinal

How mycobacterium tuberculosis infection could lead to the increasing risks of chronic fatigue syndrome and the potential immunological effects: a population-based retrospective cohort study.

Yang, Tse-Yen, Lin, Cheng-Li, Yao, Wei-Cheng et al.·Journal of translational medicine·2022

This study found that people who have had a tuberculosis infection are about 23% more likely to develop ME/CFS than people who have never had tuberculosis. Researchers in Taiwan tracked over 38,000 people for about 10 years and noticed that tuberculosis and ME/CFS share similar symptoms and immune system patterns. The link was especially strong in men and in people aged 65 and older.

Immune System

E2 ModerateCohortPEM not requiredLongitudinal

Incidence of Lyme disease in the United Kingdom and association with fatigue: A population-based, historical cohort study.

Brellier, Florence, Pujades-Rodriguez, Mar, Powell, Emma et al.·PloS one·2022

This study tracked over 2,100 people in the UK who were diagnosed with Lyme disease and compared them to similar people without Lyme disease. Researchers found that people with Lyme disease were much more likely to develop fatigue symptoms afterward, and some developed ME/CFS. Interestingly, the risk was highest when Lyme disease occurred in autumn or winter, though fatigue risks remained elevated even months after the initial infection.

E2 ModerateCohortPEM requiredObservational

A prospective observational study of post-COVID-19 chronic fatigue syndrome following the first pandemic wave in Germany and biomarkers associated with symptom severity.

Kedor, Claudia, Freitag, Helma, Meyer-Arndt, Lil et al.·Nature communications·2022

This study followed 42 people with long-lasting fatigue after COVID-19 infection for six months and compared them to people with similar chronic fatigue from other causes. Most participants experienced moderate to severe fatigue that interfered with daily life. The researchers found that many of these post-COVID patients had reduced hand grip strength and blood markers suggesting possible inflammation and poor blood flow, which may help explain why their bodies struggle to recover.

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Post-acute sequelae of SARS-CoV-2 infection: relationship of central nervous system manifestations with physical disability and systemic inflammation.

Busatto, Geraldo F, de Araujo, Adriana Ladeira, Castaldelli-Maia, João Mauricio et al.·Psychological medicine·2022

Researchers studied 749 people who had been hospitalized with COVID-19 and assessed them 6-11 months later. They found that 30 different symptoms—including fatigue, brain fog, depression, and anxiety—tend to occur together as part of one underlying condition. People with more severe symptoms also showed signs of ongoing inflammation in their blood and had greater physical disability, suggesting a real biological basis for their illness.

Cognitive Impairment

E2 ModerateCohortPEM not requiredObservational

A Comprehensive Report of German Nationwide Inpatient Data on the Post-COVID-19 Syndrome Including Annual Direct Healthcare Costs.

Walter, Nike, Rupp, Markus, Lang, Siegmund et al.·Viruses·2022

This study looked at hospital records across Germany to understand how many people were hospitalized with Post-COVID Syndrome (PCS), what treatments they received, and how much it cost the healthcare system. Researchers found nearly 30,000 hospitalized PCS patients in one year, with common problems including pneumonia, fatigue, and breathing difficulties. The total cost to the healthcare system was over €136 million, averaging about €4,583 per patient.

E2 ModerateCohortPEM not requiredCross-Sectional

Regional gray matter volume correlates to physical and mental fatigue in healthy middle-aged adults.

Putra, Handityo Aulia, Park, Kaechang, Yamashita, Fumio et al.·Neuroimage. Reports·2022

Researchers used brain scans to examine whether the size of certain brain regions relates to how tired people feel, both physically and mentally. In a large group of nearly 1,900 healthy middle-aged adults, they found that specific brain areas showed different sizes depending on fatigue levels—some areas were smaller in people reporting more fatigue, while others were larger. This suggests that brain structure may be connected to how tired we feel, even before someone develops a condition like ME/CFS.

E2 ModerateCohortPEM not requiredLongitudinal

Altered Effective Connectivity of Resting-State Networks by Tai Chi Chuan in Chronic Fatigue Syndrome Patients: A Multivariate Granger Causality Study.

Li, Yuanyuan, Wu, Kang, Hu, Xiaojie et al.·Frontiers in neurology·2022

This study looked at how a traditional Chinese exercise called Tai Chi Chuan affects the brain in ME/CFS patients. Using brain imaging, researchers found that ME/CFS patients had weaker communication between two important brain networks compared to healthy people. After just one month of Tai Chi Chuan training, this brain communication improved, and patients reported better quality of life, especially with less pain and better physical function.

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Evidence browser

Orthostatic Intolerance in Long-Haul COVID after SARS-CoV-2: A Case-Control Comparison with Post-EBV and Insidious-Onset Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients.

Subjective and objective cognitive function in adolescent with chronic fatigue following Epstein-Barr virus infection.

A 2-day cardiopulmonary exercise test in chronic fatigue syndrome patients who were exposed to humidifier disinfectants.

The Significance of Pain Drawing as a Screening Tool for Cervicogenic Headache and Associated Symptoms in Chronic Fatigue.

Intersections between pneumonia, lowered oxygen saturation percentage and immune activation mediate depression, anxiety, and chronic fatigue syndrome-like symptoms due to COVID-19: A nomothetic network approach.

ME/CFS and Post-Exertional Malaise among Patients with Long COVID.

Treatments of chronic fatigue syndrome and its debilitating comorbidities: a 12-year population-based study.

Small-Fiber Polyneuropathy Is Prevalent in Patients With Interstitial Cystitis/Bladder Pain Syndrome.

Predictors for Developing Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Following Infectious Mononucleosis.

Clinical Characteristics of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Diagnosed in Patients with Long COVID.

Metabolomic Evidence for Peroxisomal Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Plasma metabolomics reveals disrupted response and recovery following maximal exercise in myalgic encephalomyelitis/chronic fatigue syndrome.

Multimodal MRI of myalgic encephalomyelitis/chronic fatigue syndrome: A cross-sectional neuroimaging study toward its neuropathophysiology and diagnosis.

How mycobacterium tuberculosis infection could lead to the increasing risks of chronic fatigue syndrome and the potential immunological effects: a population-based retrospective cohort study.

Incidence of Lyme disease in the United Kingdom and association with fatigue: A population-based, historical cohort study.

A prospective observational study of post-COVID-19 chronic fatigue syndrome following the first pandemic wave in Germany and biomarkers associated with symptom severity.

Post-acute sequelae of SARS-CoV-2 infection: relationship of central nervous system manifestations with physical disability and systemic inflammation.

A Comprehensive Report of German Nationwide Inpatient Data on the Post-COVID-19 Syndrome Including Annual Direct Healthcare Costs.

Regional gray matter volume correlates to physical and mental fatigue in healthy middle-aged adults.

Altered Effective Connectivity of Resting-State Networks by Tai Chi Chuan in Chronic Fatigue Syndrome Patients: A Multivariate Granger Causality Study.

Curated Collections

Neuroinflammation Evidence

Metabolism & Mitochondria

Biomarkers

PEM-Specific Research