ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

341–360 of 746 studies

E2 ModerateCohortPEM requiredLongitudinal

Chronic fatigue syndrome (CFS/ME) symptom-based phenotypes and 1-year treatment outcomes in two clinical cohorts of adult patients in the UK and The Netherlands.

Collin, Simon M, Heron, Jon, Nikolaus, Stephanie et al.·Journal of psychosomatic research·2018

This study looked at different patterns of ME/CFS symptoms in nearly 2,300 patients across the UK and Netherlands to see if the types of symptoms people have when they first seek treatment predict how well they'll improve. Researchers found three main symptom patterns: patients with few extra symptoms, patients with multiple symptoms, and patients with mainly pain symptoms. After one year of treatment, patients who started with fewer symptoms were significantly more likely to feel much better, while those with many symptoms or pain-focused symptoms were less likely to improve.

Post-Exertional Malaise

E2 ModerateDiagnosticPEM requiredMethods-Paper

A Brief Questionnaire to Assess Post-Exertional Malaise.

Cotler, Joseph, Holtzman, Carly, Dudun, Catherine et al.·Diagnostics (Basel, Switzerland)·2018

This study focused on creating a better way to identify post-exertional malaise (PEM)—the worsening of symptoms that happens after physical or mental activity in ME/CFS patients. Researchers tested whether five additional questions from an existing questionnaire could help doctors confirm PEM in the second step of diagnosis. The test was successful: it correctly identified patients with ME/CFS 82% of the time and rarely misidentified other conditions like multiple sclerosis as ME/CFS.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCase-Control

Value of Circulating Cytokine Profiling During Submaximal Exercise Testing in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Moneghetti, Kegan J, Skhiri, Mehdi, Contrepois, Kévin et al.·Scientific reports·2018

Researchers tested whether measuring immune chemicals (called cytokines) in the blood after exercise could help identify people with ME/CFS. They compared 24 people with ME/CFS to 24 healthy controls and measured 51 different immune markers both before and 18 hours after exercise. They found that the pattern of immune chemicals measured 18 hours after exercise was different enough to reliably distinguish people with ME/CFS from healthy people.

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Transforming growth factor beta (TGF-β) in adolescent chronic fatigue syndrome.

Wyller, Vegard Bruun, Nguyen, Chinh Bkrong, Ludviksen, Judith Anita et al.·Journal of translational medicine·2017

This study tested whether a protein called TGF-β, which helps regulate immune and stress responses, was elevated in adolescents with ME/CFS. Researchers compared blood levels of TGF-β in 120 young ME/CFS patients to 68 healthy controls and found the protein levels were actually the same in both groups. However, they discovered that in ME/CFS patients, TGF-β levels were connected to stress hormones and fatigue severity, suggesting it may play a role in how the illness affects the body even if it's not simply 'too high.'

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Whole blood gene expression in adolescent chronic fatigue syndrome: an exploratory cross-sectional study suggesting altered B cell differentiation and survival.

Nguyen, Chinh Bkrong, Alsøe, Lene, Lindvall, Jessica M et al.·Journal of translational medicine·2017

This study looked at blood samples from 29 teenagers with ME/CFS and compared them to 18 healthy teens to see if their genes were working differently. The researchers found that certain immune cells involved in fighting infection were not developing or surviving normally in the ME/CFS group, and that signs of inflammation and antiviral activity were higher. These gene changes were connected to nervous system problems and symptoms like post-exertional malaise (feeling much worse after activity).

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Post-Exertional Malaise in Patients with ME and CFS with Comorbid Fibromyalgia.

McManimen, Stephanie L, Jason, Leonard A·SRL neurology & neurosurgery·2017

This study looked at how having fibromyalgia (FM) alongside ME/CFS affects post-exertional malaise (PEM)—the worsening of symptoms after physical or mental activity. Researchers surveyed people online about their PEM symptoms and found that those with both conditions experienced more severe and frequent PEM symptoms than those with ME/CFS alone, particularly affecting muscle pain and overall fatigue. The findings suggest that having fibromyalgia as an additional diagnosis makes ME/CFS symptoms significantly worse.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCase-Control

Cytokine responses to exercise and activity in patients with chronic fatigue syndrome: case-control study.

Clark, L V, Buckland, M, Murphy, G et al.·Clinical and experimental immunology·2017

This study examined whether people with ME/CFS have abnormal immune protein levels (cytokines) in their blood, especially after physical activity. Researchers compared 24 ME/CFS patients with 21 healthy controls and measured multiple immune markers at rest and after exercise. The study found no significant differences in immune protein levels between the two groups, and no link between post-exertional symptoms and increased cytokine levels.

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

The utility of patient-reported outcome measures among patients with myalgic encephalomyelitis/chronic fatigue syndrome.

Murdock, Kyle W, Wang, Xin Shelley, Shi, Qiuling et al.·Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation·2017

Researchers tested three common questionnaires that measure fatigue and symptoms in ME/CFS patients to see which ones work best. They found that two popular questionnaires had problems—many patients scored so high they hit the ceiling (meaning the test couldn't measure if they got worse), and the questions weren't reliable. The DePaul Symptom Questionnaire worked much better, especially at measuring post-exertional malaise (the worsening of symptoms after activity), and could reliably distinguish ME/CFS patients from healthy people.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCase-Control

The Role of Autonomic Function in Exercise-induced Endogenous Analgesia: A Case-control Study in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Healthy People.

Oosterwijck, Jessica Van, Marusic, Uros, De Wandele, Inge et al.·Pain physician·2017

This study looked at why exercise doesn't reduce pain in people with ME/CFS the way it normally does in healthy people. Researchers measured how the nervous system recovered after exercise and tracked pain levels in 20 women with ME/CFS and 20 healthy women. They found that people with ME/CFS had problems with their nervous system's ability to 'turn off' after exercise, and this was connected to their pain not improving like it should.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredObservational

Current Safety Concerns with Human Papillomavirus Vaccine: A Cluster Analysis of Reports in VigiBase®.

Chandler, Rebecca E, Juhlin, Kristina, Fransson, Jonas et al.·Drug safety·2017

Researchers analyzed thousands of reports from a global database of side effects following HPV vaccination. They found that certain combinations of symptoms—headaches, dizziness, fatigue, and fainting—were reported more often after HPV vaccination than with other vaccines, particularly in young women. These symptom clusters resemble conditions like POTS, CRPS, and chronic fatigue syndrome, though most reports did not include an official diagnosis.

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Differences in ME and CFS Symptomology in Patients with Normal and Abnormal Exercise Test Results.

McManimen, Stephanie L, Jason, Leonard A·International journal of neurology and neurotherapy·2017

This study looked at ME/CFS patients who had different results after exercise testing. Some patients showed abnormal test results and experienced severe post-exertional malaise (PEM)—that exhaustion and symptom flare-up after activity—while others had normal test results with milder PEM. The researchers found that patients with abnormal test results tended to be more disabled, experience worse PEM, and were more likely to be bedbound than those with normal results.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCase-Control

Association of biomarkers with health-related quality of life and history of stressors in myalgic encephalomyelitis/chronic fatigue syndrome patients.

Fenouillet, Emmanuel, Vigouroux, Aude, Steinberg, Jean Guillaume et al.·Journal of translational medicine·2016

This study examined blood markers and muscle function in 36 ME/CFS patients compared to 11 healthy controls to understand whether biological changes relate to symptoms and quality of life. Researchers found three key differences: problems with muscle response to exercise, increased oxidative stress (cellular damage), and changes in immune cells. These biomarkers correlated with how much ME/CFS affected patients' daily lives, especially in those whose illness started after a severe infection.

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Housebound versus nonhousebound patients with myalgic encephalomyelitis and chronic fatigue syndrome.

Pendergrast, Tricia, Brown, Abigail, Sunnquist, Madison et al.·Chronic illness·2016

This study compared ME/CFS patients who are severely ill and mostly confined to their homes with those who are less severely affected and can leave home. Researchers found that the housebound group—about 1 in 4 patients—experienced much worse physical functioning, fatigue, pain, brain fog, sleep problems, and other symptoms compared to the less severely ill group. Understanding these differences can help doctors and researchers better tailor treatments for the most severely affected patients.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Chronic fatigue syndrome (CFS) symptom-based phenotypes in two clinical cohorts of adult patients in the UK and The Netherlands.

Collin, Simon M, Nikolaus, Stephanie, Heron, Jon et al.·Journal of psychosomatic research·2016

This study looked at how ME/CFS symptoms vary from person to person by analyzing data from over 8,000 patients in the UK and Netherlands. Researchers found that ME/CFS patients fall into about 6 different groups based on which symptoms they experience—some have many symptoms, some mainly have pain, and others have very few symptoms beyond the core three (fatigue, brain fog, and sleep problems). Women and people who have been ill longer tended to have more symptoms overall.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Case definitions integrating empiric and consensus perspectives.

Jason, Leonard A, McManimen, Stephanie, Sunnquist, Madison et al.·Fatigue : biomedicine, health & behavior·2016

This study looked at 556 ME/CFS patients from three countries to understand how doctors should diagnose this condition. The researchers found that patients fall into different groups based on their symptoms: some have chronic fatigue alone, some have fatigue with other medical reasons, and some have ME/CFS with additional symptoms like problems with exercise recovery, brain fog, and sleep issues. The groups with more specific ME/CFS symptoms were significantly more disabled than those with just general fatigue.

SleepPost-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Chronic fatigue syndrome versus sudden onset myalgic encephalomyelitis.

Jason, Leonard A, Evans, Meredyth, Brown, Abigail et al.·Journal of prevention & intervention in the community·2015

This study looked at whether using a specific definition of ME (sudden onset myalgic encephalomyelitis) identifies a sicker group of patients compared to the broader CFS (chronic fatigue syndrome) definition. Researchers found that people who met the ME criteria had more severe symptoms, greater disability, and worse post-exertional malaise (feeling much worse after physical activity) than those meeting only the CFS criteria. The findings suggest that the ME definition may identify patients with more serious illness.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Examining the Institute of Medicine's Recommendations Regarding Chronic Fatigue Syndrome: Clinical Versus Research Criteria.

Jason, Leonard A, McManimen, Stephanie, Sunnquist, Madison et al.·Journal of neurology and psychology·2015

This study compared two different sets of diagnostic criteria for ME/CFS: one proposed by the Institute of Medicine for clinical use, and another (the Canadian criteria) recommended for research. Using patient data from the US, UK, and Norway, researchers found that patients meeting the research criteria were significantly more severely affected across multiple symptoms and daily functioning areas. This suggests the two criteria sets identify somewhat different groups of patients.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Timed loaded standing in female chronic fatigue syndrome compared with other populations.

Eyskens, Jan B, Nijs, Jo, D'Août, Kristiaan et al.·Journal of rehabilitation research and development·2015

Researchers tested how long women with ME/CFS could hold small weights with their arms extended straight out—a test that measures muscle endurance in the arms and trunk. Women with ME/CFS performed significantly worse than healthy women and even worse than older women with osteoporosis, suggesting a specific weakness pattern in ME/CFS. This finding could help guide rehabilitation programs that focus on movement quality rather than just building strength.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Factor Analysis of the DePaul Symptom Questionnaire: Identifying Core Domains.

Jason, Leonard A, Sunnquist, Madison, Brown, Abigail et al.·Journal of neurology and neurobiology·2015

Researchers analyzed symptom patterns in people with ME/CFS from three countries to better understand what makes this illness unique. Using statistical analysis, they found that ME/CFS symptoms naturally organize into four main groups: exhaustion that gets worse after activity, brain fog and memory problems, sleep issues, and a combination of hormone, nervous system, and immune problems. This organized way of thinking about symptoms could help doctors recognize and study the disease more effectively.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Chronic Fatigue Syndrome and Myalgic Encephalomyelitis: Toward An Empirical Case Definition.

Jason, Leonard A, Kot, Bobby, Sunnquist, Madison et al.·Health psychology and behavioral medicine·2015

Researchers studied which symptoms are most important for diagnosing ME/CFS by comparing patients with the condition to people without it. They found that four main symptoms stood out: extreme fatigue, symptom worsening after activity (called post-exertional malaise), thinking or memory problems, and sleep that doesn't feel refreshing. Using these core symptoms could help doctors diagnose ME/CFS more reliably.

Post-Exertional Malaise

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Evidence browser

Chronic fatigue syndrome (CFS/ME) symptom-based phenotypes and 1-year treatment outcomes in two clinical cohorts of adult patients in the UK and The Netherlands.

A Brief Questionnaire to Assess Post-Exertional Malaise.

Value of Circulating Cytokine Profiling During Submaximal Exercise Testing in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Transforming growth factor beta (TGF-β) in adolescent chronic fatigue syndrome.

Whole blood gene expression in adolescent chronic fatigue syndrome: an exploratory cross-sectional study suggesting altered B cell differentiation and survival.

Post-Exertional Malaise in Patients with ME and CFS with Comorbid Fibromyalgia.

Cytokine responses to exercise and activity in patients with chronic fatigue syndrome: case-control study.

The utility of patient-reported outcome measures among patients with myalgic encephalomyelitis/chronic fatigue syndrome.

The Role of Autonomic Function in Exercise-induced Endogenous Analgesia: A Case-control Study in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Healthy People.

Current Safety Concerns with Human Papillomavirus Vaccine: A Cluster Analysis of Reports in VigiBase®.

Differences in ME and CFS Symptomology in Patients with Normal and Abnormal Exercise Test Results.

Association of biomarkers with health-related quality of life and history of stressors in myalgic encephalomyelitis/chronic fatigue syndrome patients.

Housebound versus nonhousebound patients with myalgic encephalomyelitis and chronic fatigue syndrome.

Chronic fatigue syndrome (CFS) symptom-based phenotypes in two clinical cohorts of adult patients in the UK and The Netherlands.

Case definitions integrating empiric and consensus perspectives.

Chronic fatigue syndrome versus sudden onset myalgic encephalomyelitis.

Examining the Institute of Medicine's Recommendations Regarding Chronic Fatigue Syndrome: Clinical Versus Research Criteria.

Timed loaded standing in female chronic fatigue syndrome compared with other populations.

Factor Analysis of the DePaul Symptom Questionnaire: Identifying Core Domains.

Chronic Fatigue Syndrome and Myalgic Encephalomyelitis: Toward An Empirical Case Definition.

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