ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2795 studies

321–340 of 2,795 studies

E2 ModerateCohortPEM requiredObservational

Fatigue and symptom-based clusters in post COVID-19 patients: a multicentre, prospective, observational cohort study.

Cornelissen, Merel E B, Bloemsma, Lizan D, Vaes, Anouk W et al.·Journal of translational medicine·2024

This study followed 95 Dutch patients with long COVID for up to 18 months after their initial SARS-CoV-2 infection. Most patients experienced persistent fatigue, along with sleep problems, pain, and cognitive difficulties. Interestingly, over half of these patients met the diagnostic criteria for ME/CFS, and their symptom patterns resembled those seen in people with ME/CFS.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Do people with ME/CFS and joint hypermobility represent a disease subgroup? An analysis using registry data.

Mudie, Kathleen, Ramiller, Allison, Whittaker, Sadie et al.·Frontiers in neurology·2024

This study looked at whether ME/CFS patients with loose, flexible joints (joint hypermobility) form a distinct group with different symptoms and health impacts. Researchers surveyed 815 ME/CFS patients and found that about 16% had joint hypermobility. These patients reported worse quality of life, more pain, and more symptoms affecting their nervous system, thinking, digestion, and muscles compared to ME/CFS patients without joint hypermobility.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Association of physical symptoms with accelerometer-measured movement behaviors and functional capacity in individuals with Long COVID.

Rosa-Souza, Francisco José, Freire, Yuri Alberto, Galliano, Leony Morgana et al.·Scientific reports·2024

This study looked at 102 people with Long COVID to understand how specific symptoms affect their ability to move and be physically active. Researchers used activity trackers to measure daily movement and tested how far people could walk and how quickly they could stand up from a chair. They found that fatigue and post-exertional malaise (feeling worse after activity) were linked to lower daily step counts, while shortness of breath was linked to poorer performance on physical tests.

Post-Exertional Malaise

E2 ModerateGuidelinePEM unclearGuideline

Practical Recommendations for Exercise Training in Patients with Long COVID with or without Post-exertional Malaise: A Best Practice Proposal.

Gloeckl, Rainer, Zwick, Ralf H, Fürlinger, Ulrich et al.·Sports medicine - open·2024

This study created practical guidelines for exercise training in people with long COVID, especially those who experience post-exertional malaise (PEM)—when symptoms get worse after physical activity. The researchers reviewed 46 previous studies and surveyed 14 international experts to develop three different exercise approaches depending on whether someone has no PEM, mild/moderate PEM, or severe PEM. These guidelines aim to help healthcare professionals safely design exercise programs tailored to each person's specific situation.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Phase-dependent trends in the prevalence of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) related to long COVID: A criteria-based retrospective study in Japan.

Morita, Satoru, Tokumasu, Kazuki, Otsuka, Yuki et al.·PloS one·2024

This study looked at 739 patients with long COVID to understand how many developed ME/CFS and what factors were involved. Researchers found that ME/CFS affected about 8% of long COVID patients, but the rate varied depending on which COVID variant caused the initial infection—it was much higher (24%) in early COVID but dropped significantly (3%) during the Omicron wave. Brain fog complaints increased over time, even as strict ME/CFS diagnoses became less common.

Cognitive Impairment

E2 ModerateDiagnosticPEM unclearMethods-Paper

Optimizing Exclusion Criteria for Clinical Trials of Persistent Lyme Disease Using Real-World Data.

Johnson, Lorraine, Shapiro, Mira, Needell, Deanna et al.·Healthcare (Basel, Switzerland)·2024

This study looked at the rules that researchers use to decide who can join clinical trials for persistent Lyme disease (PLD). The researchers found that current rules exclude about 90% of patients, making it very hard to find enough people for studies. By relaxing some of these rules—especially those that exclude people with coexisting conditions like fibromyalgia or fatigue—researchers could include many more patients (up to 64%) while still conducting valid research.

E2 ModerateCohortPEM unclearCross-Sectional

How Long Is Long COVID? Evaluation of Long-Term Health Status in Individuals Discharged from a Specialist Community Long COVID Service.

Bodey, Rochelle, Grimaldi, Jennifer, Tait, Hannah et al.·Journal of clinical medicine·2024

This study followed people who had received specialist care for long COVID and were then discharged from the service. Nearly 3 years after their initial COVID infection, most patients (90%) still had long COVID symptoms and hadn't returned to their normal health. About 4 in 10 of these patients also met the criteria for ME/CFS, suggesting long COVID can develop into a lasting condition similar to ME/CFS.

E2 ModerateCohortPEM unclearLongitudinal

Muscle abnormalities worsen after post-exertional malaise in long COVID.

Appelman, Brent, Charlton, Braeden T, Goulding, Richie P et al.·Nature communications·2024

This study looked at muscle tissue changes in long COVID patients, particularly focusing on post-exertional malaise (PEM)—the worsening of fatigue and pain after activity. Researchers found that muscles in long COVID patients showed structural damage, metabolic problems, and unusual deposits that got worse after activity triggered PEM. These findings help explain why exertion makes symptoms worse in some long COVID patients.

Energy MetabolismPost-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Untargeted Metabolomics and Quantitative Analysis of Tryptophan Metabolites in Myalgic Encephalomyelitis Patients and Healthy Volunteers: A Comparative Study Using High-Resolution Mass Spectrometry.

Abujrais, Sandy, Vallianatou, Theodosia, Bergquist, Jonas·ACS chemical neuroscience·2024

Researchers compared blood chemistry between 38 people with ME/CFS and 24 healthy people to understand what might be different in their bodies. They found several chemical imbalances, particularly in how the body processes tryptophan (an amino acid) and in pathways related to energy production and inflammation. These differences suggest that ME/CFS patients may experience unusual immune activity and stress damage to their cells.

Energy MetabolismImmune System

E2 ModerateCohortPEM unclearCross-Sectional

The Cardiac Output-Cerebral Blood Flow Relationship Is Abnormal in Most Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients with a Normal Heart Rate and Blood Pressure Response During a Tilt Test.

van Campen, C Linda M C, Verheugt, Freek W A, Rowe, Peter C et al.·Healthcare (Basel, Switzerland)·2024

This study looked at how blood flow to the brain changes when ME/CFS patients stand up or tilt on a table. Researchers found that in 91% of patients, the heart wasn't pumping enough blood and the brain wasn't getting enough blood flow—and these two problems were directly connected. This suggests that blood vessels in the brain may not be working properly to compensate when blood flow drops, which could explain why many ME/CFS patients feel dizzy or faint when standing.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Plasma Neurofilament Light Chain: A Potential Biomarker for Neurological Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Azcue, Naiara, Tijero-Merino, Beatriz, Acera, Marian et al.·Biomedicines·2024

Researchers measured a protein called neurofilament light chain (NfL) in the blood of ME/CFS patients and healthy people. They found that ME/CFS patients had higher levels of this protein, which suggests nerve damage in the brain and nervous system. The patients with higher NfL levels also had more problems with memory, thinking clearly, and with their autonomic nervous system (the part that controls heart rate and other automatic body functions).

Autonomic Nervous SystemCognitive Impairment

E2 ModerateCohortPEM unclearCross-Sectional

Stroop task and practice effects demonstrate cognitive dysfunction in long COVID and myalgic encephalomyelitis / chronic fatigue syndrome.

Baraniuk, James N, Thapaliya, Kiran, Inderyas, Maira et al.·Scientific reports·2024

This study tested how quickly people with Long COVID and ME/CFS could complete a simple task involving reading color words displayed in different colored inks. Both patient groups were noticeably slower at this task than healthy people, and unlike healthy people, they didn't get faster with practice. This suggests that ME/CFS and Long COVID may involve a problem with how different parts of the brain communicate during problem-solving.

Cognitive Impairment

E2 ModerateCohortPEM requiredCross-Sectional

Heterogeneity in Measures of Illness among Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Is Not Explained by Clinical Practice: A Study in Seven U.S. Specialty Clinics.

Unger, Elizabeth R, Lin, Jin-Mann S, Chen, Yang et al.·Journal of clinical medicine·2024

Researchers studied 465 ME/CFS patients across seven specialized clinics in the United States to see if doctors diagnosed and recognized the same disease. They found that while the clinics had similar patients, there was tremendous variation in how sick individual patients were—some had mild symptoms while others were severely affected. This suggests that ME/CFS may naturally come in many different forms, and understanding these differences could help improve research and treatment.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredLongitudinal

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome After SARS-CoV-2 Infection.

Unger, Elizabeth R, Lin, Jin-Mann S, Wisk, Lauren E et al.·JAMA network open·2024

This study followed over 4,300 people for up to 12 months to see whether COVID-19 infection caused ME/CFS-like symptoms. Researchers found that about 3-4% of people reported ME/CFS-like symptoms after their acute illness, but this rate was similar whether they had tested positive or negative for COVID-19. The results suggest that while some people do develop long-lasting symptoms after illness, COVID-19 may not be uniquely causing ME/CFS more often than other infections.

DiagnosticsLong COVID Overlap

E2 ModerateCohortPEM unclearCross-Sectional

Diverse immunological dysregulation, chronic inflammation, and impaired erythropoiesis in long COVID patients with chronic fatigue syndrome.

Saito, Suguru, Shahbaz, Shima, Osman, Mohammed et al.·Journal of autoimmunity·2024

This study compared blood samples from long COVID patients with ME/CFS to those who fully recovered from COVID-19. Researchers found that ME/CFS patients had unusual patterns in their immune cells and higher levels of inflammation-promoting substances in their blood. They also discovered specific immune markers that could reliably distinguish ME/CFS patients from those who recovered, suggesting these markers could potentially be used for diagnosis.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Evidence of aberrant anti-epstein-barr virus antibody response, though no viral reactivation, in people with post-stroke fatigue.

Mouat, Isobel C, Zhu, Li, Aslan, Alperen et al.·Journal of inflammation (London, England)·2024

This study looked at whether Epstein-Barr virus (EBV), a common virus that stays dormant in most people's bodies, reactivates in stroke patients who experience severe fatigue. Researchers compared 44 stroke survivors—22 with high fatigue and 22 with low fatigue—and measured both the amount of active virus and antibodies against it in their blood. While they found that EBV reactivation happened equally in both groups, people with high fatigue showed unusual patterns in their immune response to the virus, suggesting their bodies may not be fighting EBV normally.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Development and Validation of the Short Form (JAEN-10) of the Joint Assessment of Equilibrium and Neuromotor Status Scale (JAEN-20).

Peinado-Rubia, Ana Belén, Osuna-Pérez, María Catalina, Núñez-Fuentes, David et al.·Journal of functional morphology and kinesiology·2024

Researchers created a shorter version of a balance and movement test (JAEN-10) to measure physical problems in people with fibromyalgia. The new 10-question test works just as well as the original 20-question version but takes less time to complete, which is helpful for people who get tired easily. The test successfully identified people with fibromyalgia and those at risk of falling.

Autonomic Nervous System

E2 ModeratePEM unclearRegistry-Resource

Longterm course of neuropsychological symptoms and ME/CFS after SARS-CoV-2-infection: a prospective registry study.

Reuken, P A, Besteher, B, Finke, K et al.·European archives of psychiatry and clinical neuroscience·2024

This study followed over 1,000 people who had long-lasting symptoms after COVID-19 infection. Researchers found that about 31% of patients met the diagnostic criteria for ME/CFS at their first visit, but this dropped to 19% at a second visit months later. While patients reported feeling less fatigued and having fewer concentration problems over time, many continued to experience long-lasting symptoms that significantly affected their daily lives.

Cognitive ImpairmentLong COVID Overlap

E2 ModeratePEM unclearRegistry-Resource

The German Multicenter Registry for ME/CFS (MECFS-R).

Hieber, Hannah, Pricoco, Rafael, Gerrer, Katrin et al.·Journal of clinical medicine·2024

German researchers created a registry to collect detailed health information from ME/CFS patients across multiple medical centers. In their first group of 174 patients, they found that most had a viral illness before developing ME/CFS, with nearly half triggered by COVID-19. Patients reported severe fatigue and greatly reduced quality of life, with significant limitations in daily activities.

Diagnostics

E2 ModerateCohortPEM unclearCross-Sectional

["The idea of rehabilitation will have to be completely rethought for this illness" - Qualitative results of an online survey on patients' experiences with inpatient rehabilitation for post COVID-19 condition (long COVID)].

Hammer, Sabine, Schmidt, Julia, Conrad, Annett et al.·Zeitschrift fur Evidenz, Fortbildung und Qualitat im Gesundheitswesen·2024

German researchers asked 1,191 long COVID patients about their experiences with inpatient rehabilitation programs. About half reported their health got worse during rehabilitation, mainly from exercise programs that were too intense. The study found that standard rehabilitation designed for other illnesses often doesn't work for long COVID patients with post-exertional malaise, and programs should instead focus on teaching patients how to pace their activities safely.

Post-Exertional Malaise

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Evidence Atlas

Evidence browser

Fatigue and symptom-based clusters in post COVID-19 patients: a multicentre, prospective, observational cohort study.

Do people with ME/CFS and joint hypermobility represent a disease subgroup? An analysis using registry data.

Association of physical symptoms with accelerometer-measured movement behaviors and functional capacity in individuals with Long COVID.

Practical Recommendations for Exercise Training in Patients with Long COVID with or without Post-exertional Malaise: A Best Practice Proposal.

Phase-dependent trends in the prevalence of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) related to long COVID: A criteria-based retrospective study in Japan.

Optimizing Exclusion Criteria for Clinical Trials of Persistent Lyme Disease Using Real-World Data.

How Long Is Long COVID? Evaluation of Long-Term Health Status in Individuals Discharged from a Specialist Community Long COVID Service.

Muscle abnormalities worsen after post-exertional malaise in long COVID.

Untargeted Metabolomics and Quantitative Analysis of Tryptophan Metabolites in Myalgic Encephalomyelitis Patients and Healthy Volunteers: A Comparative Study Using High-Resolution Mass Spectrometry.

The Cardiac Output-Cerebral Blood Flow Relationship Is Abnormal in Most Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients with a Normal Heart Rate and Blood Pressure Response During a Tilt Test.

Plasma Neurofilament Light Chain: A Potential Biomarker for Neurological Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Stroop task and practice effects demonstrate cognitive dysfunction in long COVID and myalgic encephalomyelitis / chronic fatigue syndrome.

Heterogeneity in Measures of Illness among Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Is Not Explained by Clinical Practice: A Study in Seven U.S. Specialty Clinics.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome After SARS-CoV-2 Infection.

Diverse immunological dysregulation, chronic inflammation, and impaired erythropoiesis in long COVID patients with chronic fatigue syndrome.

Evidence of aberrant anti-epstein-barr virus antibody response, though no viral reactivation, in people with post-stroke fatigue.

Development and Validation of the Short Form (JAEN-10) of the Joint Assessment of Equilibrium and Neuromotor Status Scale (JAEN-20).

Longterm course of neuropsychological symptoms and ME/CFS after SARS-CoV-2-infection: a prospective registry study.

The German Multicenter Registry for ME/CFS (MECFS-R).

["The idea of rehabilitation will have to be completely rethought for this illness" - Qualitative results of an online survey on patients' experiences with inpatient rehabilitation for post COVID-19 condition (long COVID)].

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