ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

1441–1460 of 6,157 studies

E2 ModerateCohortPEM unclearObservational

Pain Burden in Post-COVID-19 Syndrome following Mild COVID-19 Infection.

Bileviciute-Ljungar, Indre, Norrefalk, Jan-Rickard, Borg, Kristian·Journal of clinical medicine·2022

This study looked at 100 people who had mild COVID-19 but developed long-lasting symptoms afterward. Researchers asked about their pain, fatigue, sleep problems, and quality of life. Three-quarters of the participants reported widespread pain in various parts of their body, and many showed signs of fibromyalgia. The study found that pain is a major problem for people with long COVID and needs better treatment.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCase-Control

Hair cortisol levels in women with medically unexplained symptoms.

Fischer, Susanne, Skoluda, Nadine, Ali, Nida et al.·Journal of psychiatric research·2022

This study tested whether people with medically unexplained symptoms have different stress hormone levels than healthy people. Researchers measured cortisol (a stress hormone) in hair samples, which shows stress levels over the previous three months. They found that women with somatic symptom disorder (a condition involving excessive worry about physical symptoms) had lower cortisol than healthy women, but women with chronic fatigue syndrome, fibromyalgia, and irritable bowel syndrome did not differ from healthy controls.

Endocrine Disruption

E2 ModerateBehavioralPEM not requiredCross-Sectional

The psychological features of distinct somatic syndromes: A cluster analysis according to population-based somatic symptom profiles in Taiwan.

Huang, Wei-Lieh, Chang, Shu-Sen, Liao, Shih-Cheng·Journal of the Formosan Medical Association = Taiwan yi zhi·2022

This study looked at whether different types of physical symptoms (like fatigue, pain, digestive problems, and heart-related symptoms) represent separate conditions or are all part of one bigger syndrome. Researchers analyzed survey data from 550 people in Taiwan and found that people tend to cluster into four different groups based on their symptom patterns, and each group had different levels of depression, anxiety, and health worry.

E2 ModerateCohortPEM unclearCross-Sectional

A comparison of health-related factors between patients diagnosed with ME/CFS and patients with a related symptom picture but no ME/CFS diagnosis: a cross-sectional exploratory study.

Bernhoff, Gabriella, Rasmussen-Barr, Eva, Bunketorp Käll, Lina·Journal of translational medicine·2022

This study compared 205 people diagnosed with ME/CFS to 57 people with similar symptoms who were not diagnosed with ME/CFS. The researchers found that those with an ME/CFS diagnosis reported greater difficulties with physical and mental effort, more pain, and worse overall health than the undiagnosed group. Interestingly, both groups reported similar levels of anxiety, depression, and weekly physical activity, suggesting that what makes ME/CFS distinct may be specifically how the body reacts to exertion rather than activity levels alone.

E2 ModerateCohortPEM not requiredObservational

Predictors of Long COVID in Patients without Comorbidities: Data from the Polish Long-COVID Cardiovascular (PoLoCOV-CVD) Study.

Chudzik, Michał, Lewek, Joanna, Kapusta, Joanna et al.·Journal of clinical medicine·2022

This study followed 488 people without serious health conditions after they recovered from COVID-19 to see who developed Long COVID symptoms. Researchers found that people who had a severe acute COVID-19 illness, higher body weight, and joint pain during their initial infection were more likely to develop Long COVID. About 45% of those who developed Long COVID had symptoms that persisted beyond the follow-up period.

Long COVID Overlap

E2 ModerateCohortPEM requiredCross-Sectional

Chronic Fatigue and Postexertional Malaise in People Living With Long COVID: An Observational Study.

Twomey, Rosie, DeMars, Jessica, Franklin, Kelli et al.·Physical therapy·2022

This study looked at 213 people with long COVID to measure how severe their fatigue and postexertional malaise (PEM—worsening of symptoms after activity) were. Researchers found that over 71% had chronic fatigue as severe as or worse than other serious illnesses, and nearly 59% experienced PEM similar to what people with ME/CFS report. The study highlights that fatigue and symptom flare-ups after activity are major problems that need careful monitoring and should shape how doctors design rehabilitation programs.

Post-Exertional Malaise

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 requiredCross-Sectional

Somatic symptom disorder in patients with post-COVID-19 neurological symptoms: a preliminary report from the somatic study (Somatic Symptom Disorder Triggered by COVID-19).

Kachaner, Alexandra, Lemogne, Cédric, Dave, Julie et al.·Journal of neurology, neurosurgery, and psychiatry·2022

This study examined whether patients with long-lasting neurological symptoms after COVID-19 meet diagnostic criteria for somatic symptom disorder (SSD), a condition where psychological distress can amplify physical symptoms. Researchers evaluated 50 patients and found that about two-thirds met SSD criteria, though brain imaging and standard neurological tests were mostly normal. Most patients also had fatigue meeting chronic fatigue syndrome criteria, sleep problems, and significant work loss.

Sleep

E2 ModerateCohortPEM unclearCross-Sectional

Biomarkers in the diagnostic algorithm of myalgic encephalomyelitis/chronic fatigue syndrome.

Gravelsina, Sabine, Vilmane, Anda, Svirskis, Simons et al.·Frontiers in immunology·2022

This study looked for biological markers (measurable signs in the blood) that could help doctors diagnose ME/CFS more easily. Researchers tested 134 ME/CFS patients and 33 healthy people for a virus called HHV-6 and specific antibodies that attack nerve receptors. They found that ME/CFS patients had higher levels of certain antibodies compared to healthy controls, and patients with more virus in their blood tended to have more severe symptoms.

BiomarkersImmune System

E2 ModerateCohortPEM unclearCross-Sectional

The Relationship between Physical Activity and Long COVID: A Cross-Sectional Study.

Wright, Jack, Astill, Sarah L, Sivan, Manoj·International journal of environmental research and public health·2022

This study asked 477 people with Long COVID about their physical activity levels before and after illness, and how exercise affected their symptoms. Participants were much less active after getting Long COVID and needed more help with daily tasks. Most people (about 75%) reported that physical activity made their symptoms worse, while only about 1% said it improved them.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Orthostatic intolerance and neurocognitive impairment in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

Gaglio, Caroline L, Islam, Mohammed F, Cotler, Joseph et al.·Epidemiologic methods·2022

This study looked at how often people with ME/CFS experience two symptoms that doctors use to diagnose the condition: difficulty thinking clearly (brain fog, memory problems) and dizziness when standing up. The researchers found that nearly all participants reported thinking and memory problems, while only a small number had standing-up dizziness without also having cognitive problems. This suggests these two symptoms overlap heavily in ME/CFS patients.

Autonomic Nervous SystemDiagnostics

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 ModerateCohortPEM unclearCross-Sectional

Differences in Symptoms among Black and White Patients with ME/CFS.

Jason, Leonard A, Torres, Chelsea·Journal of clinical medicine·2022

This study looked at whether ME/CFS symptoms differ between Black and White patients. Researchers compared 19 Black patients with ME/CFS to White patients with ME/CFS and healthy people without the condition. They found that ME/CFS patients had notably different symptoms compared to healthy controls, but Black and White ME/CFS patients reported very similar symptom patterns.

E2 ModerateCohortPEM not requiredCase-Control

The Impact of Micro RNA-320a Serum Level on Severity of Symptoms and Cerebral Processing of Pain in Patients with Fibromyalgia.

Hussein, Mona, Fathy, Wael, Abdelaleem, Enas A et al.·Pain medicine (Malden, Mass.)·2022

Researchers measured a molecule called miR-320a in the blood of people with fibromyalgia and compared it to healthy people. They found that fibromyalgia patients had higher levels of this molecule, and those with higher levels tended to have worse symptoms like pain, fatigue, sleep problems, and depression. However, this molecule did not appear to affect how the brain processes pain signals.

Pain and SensitizationSleep

E2 ModerateCohortPEM requiredLongitudinal

Improvement of Long COVID symptoms over one year.

Oliveira, Carlos R, Jason, Leonard A, Unutmaz, Derya et al.·Frontiers in medicine·2022

This study compared people with Long COVID (PASC) to people with ME/CFS, conditions that cause similar symptoms like fatigue and brain fog. Over one year, people with Long COVID showed improvement in five key symptoms including fatigue and post-exertional malaise, while people with ME/CFS did not improve. The researchers used a symptom questionnaire to track changes and found that Long COVID and ME/CFS look similar at first, but Long COVID appears to follow a different course.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Long COVID: Association of Functional Autoantibodies against G-Protein-Coupled Receptors with an Impaired Retinal Microcirculation.

Szewczykowski, Charlotte, Mardin, Christian, Lucio, Marianna et al.·International journal of molecular sciences·2022

Some people with Long COVID have abnormal immune proteins called autoantibodies that attack blood vessel control systems in their bodies. This study found that patients with these specific autoantibodies had reduced blood flow in the tiny vessels at the back of the eye, which may reflect similar problems throughout their whole body and could explain some of their symptoms.

Immune System

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.

E2 ModerateCohortPEM unclear

Patient perceptions of infectious illnesses preceding Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Jason, Leonard A, Yoo, Samuel, Bhatia, Shaun·Chronic illness·2022

This study asked nearly 1,800 people with ME/CFS about infections they had before getting sick. About 60% of patients reported having an infection before their ME/CFS started, with mononucleosis being the most common. However, the study found that many different types of infections were reported, suggesting that ME/CFS might not be caused by just one infectious agent.

E2 ModerateCohortPEM not requiredLongitudinal

Predictors of Chronic Fatigue Syndrome and Mood Disturbance After Acute Infection.

Sandler, Carolina X, Cvejic, Erin, Valencia, Braulio M et al.·Frontiers in neurology·2022

This study followed people who had acute viral infections (EBV, Ross River virus, or Q fever) to see who developed ME/CFS-like symptoms by 6 months. About 1 in 5 participants met CFS criteria. The researchers found that people who felt more severely ill during their acute infection, and those with mood problems during that time, were more likely to have prolonged fatigue and continued mood difficulties afterward.

E2 ModerateCohortPEM not requiredLongitudinal

Impact of a mid-urethral synthetic mesh sling on long-term risk of systemic conditions in women with stress urinary incontinence: a national cohort study.

Muller, P, Gurol-Urganci, I, Thakar, R et al.·BJOG : an international journal of obstetrics and gynaecology·2022

This study looked at whether a surgical mesh implant used to treat urinary leakage in women increases the risk of developing systemic diseases like autoimmune conditions, fibromyalgia, or ME/CFS. Researchers compared nearly 89,000 women who received mesh surgery to about 3,400 women who had surgery without mesh, following them for up to 10 years. The study found no evidence that mesh surgery increased the risk of these systemic conditions.

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Pain Burden in Post-COVID-19 Syndrome following Mild COVID-19 Infection.

Hair cortisol levels in women with medically unexplained symptoms.

The psychological features of distinct somatic syndromes: A cluster analysis according to population-based somatic symptom profiles in Taiwan.

A comparison of health-related factors between patients diagnosed with ME/CFS and patients with a related symptom picture but no ME/CFS diagnosis: a cross-sectional exploratory study.

Predictors of Long COVID in Patients without Comorbidities: Data from the Polish Long-COVID Cardiovascular (PoLoCOV-CVD) Study.

Chronic Fatigue and Postexertional Malaise in People Living With Long COVID: An Observational Study.

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.

Somatic symptom disorder in patients with post-COVID-19 neurological symptoms: a preliminary report from the somatic study (Somatic Symptom Disorder Triggered by COVID-19).

Biomarkers in the diagnostic algorithm of myalgic encephalomyelitis/chronic fatigue syndrome.

The Relationship between Physical Activity and Long COVID: A Cross-Sectional Study.

Orthostatic intolerance and neurocognitive impairment in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

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

Differences in Symptoms among Black and White Patients with ME/CFS.

The Impact of Micro RNA-320a Serum Level on Severity of Symptoms and Cerebral Processing of Pain in Patients with Fibromyalgia.

Improvement of Long COVID symptoms over one year.

Long COVID: Association of Functional Autoantibodies against G-Protein-Coupled Receptors with an Impaired Retinal Microcirculation.

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

Patient perceptions of infectious illnesses preceding Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Predictors of Chronic Fatigue Syndrome and Mood Disturbance After Acute Infection.

Impact of a mid-urethral synthetic mesh sling on long-term risk of systemic conditions in women with stress urinary incontinence: a national cohort study.

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Biomarkers

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