ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2795 studies

681–700 of 2,795 studies

E2 ModerateCohortPEM unclearCase-Control

Central sensitisation in chronic fatigue syndrome and fibromyalgia; a case control study.

Bourke, Julius H, Wodehouse, Theresa, Clark, Lucy V et al.·Journal of psychosomatic research·2021

This study tested whether ME/CFS and fibromyalgia involve a condition called 'central sensitisation,' where the nervous system becomes overly sensitive to pain signals. Researchers compared pain sensitivity in 19 ME/CFS patients, 19 fibromyalgia patients, and 20 healthy people using physical tests. They found that 84% of ME/CFS patients and 95% of fibromyalgia patients showed signs of central sensitisation, while none of the healthy controls did.

Pain and Sensitization

E2 ModerateCohortPEM requiredCase-Control

Female Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome or Idiopathic Chronic Fatigue: Comparison of Responses to a Two-Day Cardiopulmonary Exercise Testing Protocol.

van Campen, C Linda M C, Visser, Frans C·Healthcare (Basel, Switzerland)·2021

This study tested whether people with ME/CFS and people with chronic fatigue (but not ME/CFS) respond differently to exercise on two consecutive days. Researchers had 50 women with ME/CFS and 51 women with chronic fatigue perform exercise tests while measuring oxygen use and heart rate. Women with ME/CFS performed worse on day 2, while women with chronic fatigue actually performed slightly better, suggesting ME/CFS creates a unique pattern of exercise intolerance.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCase-Control

Health, Wellbeing, and Prognosis of Australian Adolescents with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Case-Controlled Follow-Up Study.

Josev, Elisha K, Cole, Rebecca C, Scheinberg, Adam et al.·Journal of clinical medicine·2021

This study followed Australian teenagers with ME/CFS for about two years after diagnosis to see how they were doing. While many young people improved in mood and some symptoms, fatigue, pain, and overall quality of life stayed significantly worse compared to healthy teenagers. About two-thirds of the teens still had ME/CFS at follow-up, suggesting the condition often persists in the early years after diagnosis.

Pain and Sensitization

E2 ModerateCohortPEM requiredObservational

Markers of Cardiac Autonomic Function During Consecutive Day Peak Exercise Tests in People With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Nelson, Maximillian J, Buckley, Jonathan D, Thomson, Rebecca L et al.·Frontiers in physiology·2021

This study looked at how the hearts of ME/CFS patients respond to exercise on two consecutive days, comparing them to healthy people. Researchers measured heart rate patterns and recovery after exercise, finding that ME/CFS patients had slower heart rate recovery after working out. However, these measurements alone were not reliable enough to diagnose ME/CFS, suggesting that a single heart rate test may not be a useful diagnostic tool on its own.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

The Epidemiology of Insomnia and Sleep Duration Across Mental and Physical Health: The SHoT Study.

Sivertsen, Børge, Hysing, Mari, Harvey, Allison G et al.·Frontiers in psychology·2021

This study looked at sleep problems in over 50,000 Norwegian college students and found that insomnia (difficulty sleeping) is much more common in people with both mental and physical health conditions. Students with ME/CFS had particularly high rates of insomnia—about 65% of women and an unspecified percentage of men experienced insomnia when they also had ME/CFS. The study also found that people with these conditions slept shorter amounts overall.

Sleep

E2 ModerateCohortPEM unclearObservational

Warning Signals of Post-Exertional Malaise in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Retrospective Analysis of 197 Patients.

Ghali, Alaa, Lacout, Carole, Ghali, Maria et al.·Journal of clinical medicine·2021

This study looked at whether certain new or unusual symptoms might warn ME/CFS patients that a post-exertional malaise (PEM) flare is coming. Researchers reviewed medical records from 197 ME/CFS patients and found that about 14% experienced mood changes or other new symptoms before their baseline symptoms got worse. Interestingly, these patients had less intense PEM flares than those without warning symptoms, suggesting these early signals might help patients prepare or prevent more severe crashes.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Postural orthostatic tachycardia syndrome in patients of orthostatic intolerance symptoms: an ambispective study.

Chouksey, Dinesh, Rathi, Pankaj, Sodani, Ajoy et al.·AIMS neuroscience·2021

This study looked at patients who experience dizziness, fainting, or heart racing when standing up—symptoms of a condition called POTS (Postural Orthostatic Tachycardia Syndrome). Researchers tested 246 patients with these symptoms and confirmed POTS in 40 of them using a special tilt-table test. Most POTS patients experienced fainting, lightheadedness, and heart palpitations, and nearly half also had a related condition causing fainting.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Co-occurrence of immune-mediated conditions and endometriosis among adolescents and adult women.

Shafrir, Amy L, Palmor, Marissa C, Fourquet, Jessica et al.·American journal of reproductive immunology (New York, N.Y. : 1989)·2021

This study looked at whether young women and adolescents with endometriosis (a painful condition where tissue grows outside the uterus) are more likely to have immune system problems like allergies, asthma, or chronic fatigue. Researchers compared 551 women with surgically confirmed endometriosis to 652 women without it and found that those with endometriosis were significantly more likely to have chronic fatigue syndrome, fibromyalgia, or a history of mononucleosis. The more immune-related conditions a woman had, the higher her chances of also having endometriosis.

Immune System

E2 ModerateCohortPEM not requiredLongitudinal

Inflammation-type dysbiosis of the oral microbiome associates with the duration of COVID-19 symptoms and long COVID.

Haran, John P, Bradley, Evan, Zeamer, Abigail L et al.·JCI insight·2021

This study looked at bacteria in the mouth of people with COVID-19 to understand why some people develop long COVID. Researchers found that people with long COVID had higher levels of inflammation-causing bacteria, particularly types called Prevotella and Veillonella. Interestingly, the oral bacteria patterns in long COVID patients resembled those seen in chronic fatigue syndrome patients, suggesting the microbiome may play a role in prolonged illness.

Immune System

E2 ModerateCohortPEM requiredCase-Control

Hypothalamic-Pituitary Autoimmunity and Related Impairment of Hormone Secretions in Chronic Fatigue Syndrome.

De Bellis, Annamaria, Bellastella, Giuseppe, Pernice, Vlenia et al.·The Journal of clinical endocrinology and metabolism·2021

This study looked for specific immune system antibodies that attack the pituitary and hypothalamus—two small brain structures that control hormone production—in people with ME/CFS. Researchers found these antibodies in more than half of ME/CFS patients but none in healthy controls. Patients with these antibodies had lower levels of important hormones (like cortisol and growth hormone), and those with the highest antibody levels had the most severe ME/CFS symptoms.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

Comparative Survey of People with ME/CFS in Italy, Latvia, and the UK: A Report on Behalf of the Socioeconomics Working Group of the European ME/CFS Research Network (EUROMENE).

Brenna, Elenka, Araja, Diana, Pheby, Derek F H·Medicina (Kaunas, Lithuania)·2021

Researchers surveyed people with ME/CFS in Italy, Latvia, and the UK to understand how the disease affects their lives and finances. They found that ME/CFS has a serious impact on income and quality of life across all three countries, and that graded exercise therapy (a treatment commonly used in the UK) did not work for patients. The study also revealed differences in how doctors diagnose and treat ME/CFS depending on which country people live in.

E2 ModerateCohortPEM not requiredCross-Sectional

A retrospective cross-sectional study on tinnitus prevalence and disease associations in the Dutch population-based cohort Lifelines.

Schubert, Nick M A, Rosmalen, Judith G M, van Dijk, Pim et al.·Hearing research·2021

This study looked at how common tinnitus (ringing in the ears) is in a large group of Dutch adults and found that about one-third experience it at some point. The researchers discovered that tinnitus is linked to various conditions including hearing problems, heart issues, depression, and notably, chronic fatigue syndrome (ME/CFS). Understanding these connections may help doctors better treat tinnitus and related conditions.

E2 ModerateCohortPEM unclearCross-Sectional

Complement Component C1q as a Potential Diagnostic Tool for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Subtyping.

Castro-Marrero, Jesús, Zacares, Mario, Almenar-Pérez, Eloy et al.·Journal of clinical medicine·2021

Researchers analyzed blood samples from 250 women with ME/CFS to see if specific blood markers could help identify different types of the disease. They found that about 43% of participants had high levels of a protein called C1q, which was particularly associated with those experiencing more pain symptoms. This discovery suggests that blood tests might one day help doctors identify which ME/CFS patients belong to which subgroup, potentially leading to better tailored treatments.

Immune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue of nurses in view of the challenges of contemporary psychiatric care. Do temperament and work environment matter?

Sygit-Kowalkowska, Ewa·Psychiatria polska·2021

This study looked at fatigue in psychiatric nurses and found that most experienced moderate to high levels of chronic fatigue. The research suggests that workplace communication problems—like unclear instructions and poor teamwork—may contribute to this fatigue, and that some people's personality traits may make them more resilient to fatigue than others.

E2 ModerateCohortPEM requiredCross-Sectional

Homebound versus Bedridden Status among Those with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Conroy, Karl, Bhatia, Shaun, Islam, Mohammed et al.·Healthcare (Basel, Switzerland)·2021

This study looked at over 2,100 people with ME/CFS to understand different levels of severity, focusing on those who are homebound (unable to leave home) and bedridden (unable to leave bed). The researchers found that people who are bedridden experience post-exertional malaise (PEM)—a worsening of symptoms after physical or mental activity—differently or more severely than those who are only homebound. This research helps doctors and patients better understand how severe ME/CFS can become.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Patients with Persistent Polyclonal B-Cell Lymphocytosis Share the Symptomatic Criteria of Systemic Exertion Intolerance Disease.

Morizot, Romain, de Korwin, Jean-Dominique, Feugier, Pierre et al.·Journal of clinical medicine·2021

Researchers studied a rare blood condition called persistent polyclonal B-cell lymphocytosis (PPBL) and found that most patients with PPBL experience symptoms very similar to ME/CFS, including severe fatigue that doesn't improve with rest, worsening after physical activity, sleep problems, and difficulty thinking clearly. Out of 39 patients surveyed, 72% met the official criteria for ME/CFS, and nearly all reported chronic fatigue lasting more than 6 months. This finding suggests these two conditions may share common underlying features, though more research is needed to understand why.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Monitoring treatment harm in myalgic encephalomyelitis/chronic fatigue syndrome: A freedom-of-information study of National Health Service specialist centres in England.

McPhee, Graham, Baldwin, Adrian, Kindlon, Tom et al.·Journal of health psychology·2021

This study looked at how 38 ME/CFS specialist clinics in England monitor and report harms from treatments like graded exercise therapy and cognitive behavioural therapy. Researchers found that clinics were inconsistent in how they handle treatment-related harm, rarely warned patients about potential risks in their written materials, and reported zero cases of harm despite knowing many patients dropped out of treatment. The study suggests clinics need better systems to detect, record, and stop treatments when patients are being harmed.

E2 ModerateCohortPEM not requiredCross-Sectional

Chronotropic Incompetence in Non-Hospitalized Patients with Post-COVID-19 Syndrome.

Jimeno-Almazán, Amaya, Pallarés, Jesús G, Buendía-Romero, Ángel et al.·Journal of clinical medicine·2021

Some people who recover from COVID-19 experience persistent fatigue and difficulty exercising for months afterward. This study tested 32 people with long-lasting COVID symptoms and found that about 12% had a specific heart problem called chronotropic incompetence—their heart rate doesn't increase normally during exercise. This heart rhythm problem may explain why some patients struggle with exercise intolerance after COVID-19.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Characterizing long COVID in an international cohort: 7 months of symptoms and their impact.

Davis, Hannah E, Assaf, Gina S, McCorkell, Lisa et al.·EClinicalMedicine·2021

This study surveyed nearly 3,800 people from around the world who had long-lasting COVID-19 symptoms lasting more than 28 days. By seven months after illness onset, most participants had not fully recovered and experienced an average of 56 symptoms affecting multiple body systems. The three most persistent symptoms were fatigue, post-exertional malaise (feeling worse after activity), and cognitive problems, with nearly 86% experiencing relapses triggered by exercise, physical activity, mental stress, or other exertion.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Medical Care Situation of People with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Germany.

Froehlich, Laura, Hattesohl, Daniel B R, Jason, Leonard A et al.·Medicina (Kaunas, Lithuania)·2021

This study surveyed nearly 500 people with ME/CFS in Germany to understand how well they can access medical care and how satisfied they are with the care they receive. The researchers found that many patients struggle to get medical help because of cost and distance, and many are unhappy with their doctors' care. The study also created and tested a German language symptom questionnaire that could help doctors diagnose ME/CFS.

Post-Exertional Malaise

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Central sensitisation in chronic fatigue syndrome and fibromyalgia; a case control study.

Female Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome or Idiopathic Chronic Fatigue: Comparison of Responses to a Two-Day Cardiopulmonary Exercise Testing Protocol.

Health, Wellbeing, and Prognosis of Australian Adolescents with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Case-Controlled Follow-Up Study.

Markers of Cardiac Autonomic Function During Consecutive Day Peak Exercise Tests in People With Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

The Epidemiology of Insomnia and Sleep Duration Across Mental and Physical Health: The SHoT Study.

Warning Signals of Post-Exertional Malaise in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Retrospective Analysis of 197 Patients.

Postural orthostatic tachycardia syndrome in patients of orthostatic intolerance symptoms: an ambispective study.

Co-occurrence of immune-mediated conditions and endometriosis among adolescents and adult women.

Inflammation-type dysbiosis of the oral microbiome associates with the duration of COVID-19 symptoms and long COVID.

Hypothalamic-Pituitary Autoimmunity and Related Impairment of Hormone Secretions in Chronic Fatigue Syndrome.

Comparative Survey of People with ME/CFS in Italy, Latvia, and the UK: A Report on Behalf of the Socioeconomics Working Group of the European ME/CFS Research Network (EUROMENE).

A retrospective cross-sectional study on tinnitus prevalence and disease associations in the Dutch population-based cohort Lifelines.

Complement Component C1q as a Potential Diagnostic Tool for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Subtyping.

Chronic fatigue of nurses in view of the challenges of contemporary psychiatric care. Do temperament and work environment matter?

Homebound versus Bedridden Status among Those with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Patients with Persistent Polyclonal B-Cell Lymphocytosis Share the Symptomatic Criteria of Systemic Exertion Intolerance Disease.

Monitoring treatment harm in myalgic encephalomyelitis/chronic fatigue syndrome: A freedom-of-information study of National Health Service specialist centres in England.

Chronotropic Incompetence in Non-Hospitalized Patients with Post-COVID-19 Syndrome.

Characterizing long COVID in an international cohort: 7 months of symptoms and their impact.

Medical Care Situation of People with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Germany.

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