ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

421–440 of 2,768 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Medical assistance in dying when natural death is not reasonably foreseeable: Survey of providers' experiences with patients making track 2 requests.

Wiebe, Ellen, Kelly, Michaela·Canadian family physician Medecin de famille canadien·2023

This study looked at how doctors in Canada handled requests from patients with serious chronic illnesses who asked for medical assistance in dying (MAID) between March and September 2021. Among 54 patients who made these requests, about 15% had ME/CFS or similar complex chronic conditions, and 52% had chronic pain. Doctors reported struggling most with patients who also had mental health conditions and uncertainty about whether patients had tried all available treatments.

E2 ModerateCohortPEM unclearCross-Sectional

COVID-19: Post-recovery Manifestations.

Shaikh, Safia, Siddiqi, Zunaira, Ukachukwu, Crystal et al.·Cureus·2023

This study asked nearly 200 people recovering from COVID-19 about their symptoms. Most patients (85%) reported ongoing problems after infection, with fatigue being the most common complaint (59%). Other frequent problems included reduced physical stamina (49%), shortness of breath (33%), and anxiety (24%). The symptoms resembled those seen in ME/CFS, though the study did not confirm a direct connection.

E2 ModerateCohortPEM requiredCross-Sectional

Characterizing Sjögren-Associated Fatigue: A Distinct Phenotype from ME/CFS.

Kim, Laura, Kedor, Claudia, Buttgereit, Frank et al.·Journal of clinical medicine·2023

This study compared fatigue in people with Sjögren's syndrome (an autoimmune disease affecting moisture-producing glands) to fatigue in ME/CFS patients. While both groups experience severe tiredness, the researchers found important differences: Sjögren's patients recovered their muscle strength within an hour of activity, whereas ME/CFS patients typically experience worsening symptoms hours after exertion. Only a small portion of Sjögren's patients met ME/CFS diagnostic criteria, suggesting these are distinct conditions despite some symptom overlap.

Severe MEPost-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Focus on post-exertional malaise when approaching ME/CFS in specialist healthcare improves satisfaction and reduces deterioration.

Wormgoor, Marjon E A, Rodenburg, Sanne C·Frontiers in neurology·2023

This study looked at whether ME/CFS specialists in Norway were paying attention to post-exertional malaise (PEM)—the worsening of symptoms after physical or mental effort, which is a key feature of ME/CFS. They surveyed nearly 900 patients about their experiences in specialist clinics and hospitals. The results showed that when doctors focused on PEM and helped patients avoid overexertion, patients felt better, were more satisfied with their care, and were less likely to get worse after treatment.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Increased gut permeability and bacterial translocation are associated with fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome: implications for disease-related biomarker discovery.

Martín, Franz, Blanco-Suárez, Manuel, Zambrano, Paola et al.·Frontiers in immunology·2023

This study found that people with ME/CFS and fibromyalgia may have a 'leaky gut'—where the intestinal barrier doesn't work as well as it should. Researchers measured several substances in the blood that indicate gut barrier problems and inflammation, and found higher levels in both patient groups compared to healthy people. These findings suggest that gut dysfunction might play a role in these conditions and could eventually help doctors identify and understand these diseases better.

Immune System

E2 ModerateCohortPEM requiredCross-Sectional

An international survey of experiences and attitudes towards pacing using a heart rate monitor for people with myalgic encephalomyelitis/chronic fatigue syndrome.

Clague-Baker, Nicola, Davenport, Todd E, Madi, Mohammad et al.·Work (Reading, Mass.)·2023

This study asked 488 people with ME about their experiences using heart rate monitors to help manage their activity levels. Heart rate monitors can help you stay within a safe activity zone that doesn't trigger post-exertional malaise (the worsening of symptoms after activity). Most people in the study found that heart rate monitors helped them understand their condition better, reduce symptom severity, and even gradually increase what they could do—including returning to some work. However, people also reported challenges, so more research and better training for doctors is needed.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredLongitudinal

Long-term symptom severity and clinical biomarkers in post-COVID-19/chronic fatigue syndrome: results from a prospective observational cohort.

Legler, Franziska, Meyer-Arndt, Lil, Mödl, Lukas et al.·EClinicalMedicine·2023

This study followed 106 people with long-term fatigue after COVID-19 for up to 20 months to see how they recovered over time. Researchers found that some patients met the diagnostic criteria for ME/CFS and had persistent, severe symptoms including fatigue and post-exertional malaise (worsening after activity), while others improved more substantially. Lower muscle strength at the start of illness was linked to ongoing symptoms, especially in those with ME/CFS.

BiomarkersImmune SystemPost-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Lowered oxygen saturation and increased body temperature in acute COVID-19 largely predict chronic fatigue syndrome and affective symptoms due to Long COVID: A precision nomothetic approach.

Al-Hadrawi, Dhurgham Shihab, Al-Rubaye, Haneen Tahseen, Almulla, Abbas F et al.·Acta neuropsychiatrica·2023

This study examined whether low oxygen levels and high fever during acute COVID-19 could predict who develops Long COVID symptoms like fatigue, depression, and anxiety. Researchers found that these two early warning signs, combined with being female, could explain about 61% of why some people develop these lingering symptoms. They also identified a subgroup (about 27% of Long COVID patients) with particularly severe oxygen drops and fever who experienced the worst combination of fatigue, mood problems, and digestive symptoms.

Long COVID Overlap

E2 ModerateCohortPEM not required

Hypothalamus volumes in adolescent Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): impact of self-reported fatigue and illness duration.

Byrne, Hollie, Josev, Elisha K, Knight, Sarah J et al.·Brain structure & function·2023

This study looked at the size of the hypothalamus (a small part of the brain that controls many body functions) in teenagers with ME/CFS compared to healthy teenagers. While the overall brain structure sizes were similar between the two groups, researchers found that in ME/CFS patients, certain areas of the hypothalamus were slightly larger when fatigue was more severe, and other areas grew larger with longer illness duration. This suggests the hypothalamus may play a role in ME/CFS, though more research is needed to understand what this means.

E2 ModerateCohortPEM unclearCross-Sectional

The economic burden of myalgic encephalomyelitis/chronic fatigue syndrome in Australia.

Zhao, Ting, Cox, Ingrid A, Ahmad, Hasnat et al.·Australian health review : a publication of the Australian Hospital Association·2023

This study looked at how much money ME/CFS costs patients, their families, and Australia as a whole. Researchers surveyed 175 Australian patients and found that ME/CFS costs about $63,400 per person each year on average. Most of these costs come from lost work and productivity, plus care provided by family members, rather than from doctor visits and medicines. People with severe ME/CFS have much higher costs than those with milder forms.

E2 ModerateCohortPEM unclearLongitudinal

Different risk factors distinguish myalgic encephalomyelitis/chronic fatigue syndrome from severe fatigue.

Palacios, Natalia, Molsberry, Samantha, Fitzgerald, Kathryn C et al.·Scientific reports·2023

This study examined whether ME/CFS is simply an extreme version of regular fatigue, or if it's a fundamentally different condition. Researchers surveyed over 41,000 nurses and found that ME/CFS and severe fatigue have different risk factors—meaning different things cause them. This suggests that ME/CFS is a distinct condition with its own underlying biology, not just 'really bad tiredness.'

Diagnostics

E2 ModerateCohortPEM requiredCross-Sectional

Pediatric Post-Acute Sequelae of SARS-CoV-2 Infection.

Jason, Leonard A, Johnson, Madeline, Torres, Chelsea·Fatigue : biomedicine, health & behavior·2023

This study compared young people recovering from long COVID (PASC) with young people who have ME/CFS to understand how their symptoms differ. Researchers asked 19 parents about their child's symptoms during initial COVID infection and again later, then compared these to 19 young people with ME/CFS. Most PASC symptoms improved over time, but fatigue and sleep problems stayed high—similar to what ME/CFS patients experience.

SleepPost-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

The physio-affective phenome of major depression is strongly associated with biomarkers of astroglial and neuronal projection toxicity which in turn are associated with peripheral inflammation, insulin resistance and lowered calcium.

Al-Hakeim, Hussein Kadhem, Al-Naqeeb, Tabarek Hadi, Almulla, Abbas F et al.·Journal of affective disorders·2023

This study examined whether brain and nerve damage markers in the blood are connected to depression symptoms and other physical complaints. Researchers measured several proteins in the blood of people with depression and compared them to healthy controls, finding that markers of brain cell and nerve damage—along with inflammation and insulin resistance—together explained about 61% of the severity of depression, anxiety, fatigue, and physical symptoms.

NeuroinflammationBiomarkers

E2 ModerateCohortPEM unclearCross-Sectional

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): A preliminary survey among patients in Switzerland.

Tschopp, Rea, König, Rahel S, Rejmer, Protazy et al.·Heliyon·2023

This Swiss study surveyed 169 ME/CFS patients to understand their experiences with the illness. Most patients were women, many couldn't work, and about half said their condition was getting worse over time. The study found that infections—especially viral ones like Epstein-Barr virus—often happened before people developed ME/CFS, and patients reported many different symptoms that got worse with certain triggers.

E2 ModerateCohortPEM unclearObservational

Skin Temperature Circadian Rhythms and Dysautonomia in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Role of Endothelin-1 in the Vascular Tone Dysregulation.

Cambras, Trinitat, Zerón-Rugerio, Maria Fernanda, Díez-Noguera, Antoni et al.·International journal of molecular sciences·2023

This study looked at how the bodies of people with ME/CFS respond to position changes and whether problems with their blood vessel function might be involved. Researchers compared 67 women with ME/CFS to 48 healthy women, measuring their blood pressure, heart rate, body temperature patterns, and blood markers related to blood vessel health. They found that people with ME/CFS had higher blood pressure and heart rate, disrupted daily temperature rhythms, and elevated levels of substances in the blood that suggest blood vessel problems.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredLongitudinal

Single and repeated high-level blast, low-level blast, and new-onset self-reported health conditions in the U.S. Millennium Cohort Study: An exploratory investigation.

Belding, Jennifer N, Kolaja, Claire A, Rull, Rudolph P et al.·Frontiers in neurology·2023

This study followed a large group of U.S. military personnel and veterans to investigate whether exposure to blast pressure—both from single or repeated high-level blasts and occupational low-level blast exposure—was associated with new health diagnoses. Researchers found that blast exposure was linked to several conditions including chronic fatigue syndrome, PTSD, hearing loss, depression, and nerve damage. The study suggests that repeated blast exposure may carry greater health risks than single exposure, and that combinations of different blast exposures may increase risks further.

E2 ModerateCohortPEM unclearObservational

Sex differences in post-exercise fatigue and function in myalgic encephalomyelitis/chronic fatigue syndrome.

Friedberg, Fred, Adamowicz, Jenna L, Bruckenthal, Patricia et al.·Scientific reports·2023

This study looked at how men and women with ME/CFS respond differently to a simple exercise test (a six-minute walk). Researchers tracked fatigue levels and heart function for 15 days in 37 ME/CFS patients and 14 healthy people. Women with ME/CFS felt more tired after the first walk test, while men reported fewer work limitations in the days after exercise. Surprisingly, the study did not find the expected differences between men and women in how long it took to recover.

Post-Exertional Malaise

E2 ModerateDiagnosticPEM requiredCross-Sectional

Evaluating case diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): toward an empirical case definition.

Conroy, Karl E, Islam, Mohammed F, Jason, Leonard A·Disability and rehabilitation·2023

This study looked at how doctors diagnose ME/CFS by analyzing symptoms reported by over 2,300 patients from around the world. Researchers used statistical methods to identify which symptoms tend to occur together, then compared their findings to three existing diagnostic guidelines. They found that the symptoms cluster into seven main groups, with post-exertional malaise (worsening after activity), cognitive problems, and sleep issues being particularly important.

SleepPost-Exertional Malaise

E2 ModerateCohortPEM unclearObservational

Utility of Serum Ferritin for Predicting Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Patients with Long COVID.

Yamamoto, Yukichika, Otsuka, Yuki, Tokumasu, Kazuki et al.·Journal of clinical medicine·2023

This study looked at 234 people with long COVID to understand why some developed ME/CFS (a severe fatigue condition) while others didn't. Researchers found that people who developed ME/CFS had significantly higher levels of ferritin, a protein that stores iron, in their blood compared to those with long COVID fatigue alone or no fatigue. The finding was especially strong in women, suggesting that a simple blood test measuring ferritin might help predict who is at risk of developing ME/CFS after COVID-19.

Biomarkers

E2 ModerateCohortPEM requiredCross-Sectional

Do diagnostic criteria for ME matter to patient experience with services and interventions? Key results from an online RDS survey targeting fatigue patients in Norway.

Kielland, Anne, Liu, Jing, Jason, Leonard A·Journal of health psychology·2023

This study surveyed 660 people with ME/CFS in Norway to understand how different diagnostic criteria and symptoms affect their experiences with treatments and healthcare services. Most patients reported that available interventions had little benefit or made them feel worse. The researchers found that post-exertional malaise (a hallmark symptom where activity makes fatigue and other symptoms worse) was strongly linked to how patients tolerated different treatments, suggesting this symptom should be a key consideration when recommending interventions.

Post-Exertional Malaise

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Evidence browser

Medical assistance in dying when natural death is not reasonably foreseeable: Survey of providers' experiences with patients making track 2 requests.

COVID-19: Post-recovery Manifestations.

Characterizing Sjögren-Associated Fatigue: A Distinct Phenotype from ME/CFS.

Focus on post-exertional malaise when approaching ME/CFS in specialist healthcare improves satisfaction and reduces deterioration.

Increased gut permeability and bacterial translocation are associated with fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome: implications for disease-related biomarker discovery.

An international survey of experiences and attitudes towards pacing using a heart rate monitor for people with myalgic encephalomyelitis/chronic fatigue syndrome.

Long-term symptom severity and clinical biomarkers in post-COVID-19/chronic fatigue syndrome: results from a prospective observational cohort.

Lowered oxygen saturation and increased body temperature in acute COVID-19 largely predict chronic fatigue syndrome and affective symptoms due to Long COVID: A precision nomothetic approach.

Hypothalamus volumes in adolescent Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): impact of self-reported fatigue and illness duration.

The economic burden of myalgic encephalomyelitis/chronic fatigue syndrome in Australia.

Different risk factors distinguish myalgic encephalomyelitis/chronic fatigue syndrome from severe fatigue.

Pediatric Post-Acute Sequelae of SARS-CoV-2 Infection.

The physio-affective phenome of major depression is strongly associated with biomarkers of astroglial and neuronal projection toxicity which in turn are associated with peripheral inflammation, insulin resistance and lowered calcium.

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): A preliminary survey among patients in Switzerland.

Skin Temperature Circadian Rhythms and Dysautonomia in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Role of Endothelin-1 in the Vascular Tone Dysregulation.

Single and repeated high-level blast, low-level blast, and new-onset self-reported health conditions in the U.S. Millennium Cohort Study: An exploratory investigation.

Sex differences in post-exercise fatigue and function in myalgic encephalomyelitis/chronic fatigue syndrome.

Evaluating case diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): toward an empirical case definition.

Utility of Serum Ferritin for Predicting Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Patients with Long COVID.

Do diagnostic criteria for ME matter to patient experience with services and interventions? Key results from an online RDS survey targeting fatigue patients in Norway.

Curated Collections

Neuroinflammation Evidence

Metabolism & Mitochondria

Biomarkers

PEM-Specific Research