ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

1381–1400 of 6,188 studies

E2 ModerateCohortPEM unclearObservational

Pattern of Post COVID Fatigue in Elderly Patients.

Gaber, Tarek A·Advances in rehabilitation science and practice·2023

This study looked at why older adults (especially those over 70) seem to report Long COVID fatigue less often than younger people. Rather than assuming older adults simply don't report symptoms, the researchers found that older people who do get post-COVID fatigue experience it differently—it doesn't seem to follow the typical pattern of getting worse after physical activity. The study suggests that changes in how aging bodies work (in immunity, metabolism, and genes) might explain why fatigue after COVID looks different in elderly patients.

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 ModerateBehavioralPEM unclearLongitudinal

The relevance of pacing strategies in managing symptoms of post-COVID-19 syndrome.

Ghali, Alaa, Lacombe, Valentin, Ravaiau, Camille et al.·Journal of translational medicine·2023

This study looked at whether pacing—a strategy where patients carefully manage their activity levels to avoid overexertion—helps people recover from long COVID. Researchers followed 86 patients for about 10 months and found that about one-third returned to work and another quarter improved significantly. Patients who stuck with pacing strategies most consistently had the best outcomes, with 60% recovering compared to only 5.5% of those who didn't follow pacing closely.

Interventions

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 unclearCross-Sectional

The Conners Continuous Performance Test CPT3™: Is it a reliable marker to predict neurocognitive dysfunction in Myalgic encephalomyelitis/chronic fatigue syndrome?

Fernández-Quirós, Judith, Lacasa-Cazcarra, Marcos, Alegre-Martín, Jose et al.·Frontiers in psychology·2023

This study tested whether a computer-based attention test called CPT3™ can reliably detect thinking and concentration problems in ME/CFS patients. Researchers compared 158 ME/CFS patients with 67 healthy people and found that ME/CFS patients performed significantly worse on measures of attention, focus, and reaction speed. The test successfully identified differences between the two groups, suggesting it could be a useful tool for doctors to help diagnose or monitor ME/CFS.

Cognitive Impairment

E2 ModerateCohortPEM unclearObservational

Physical Activity Effects on Muscle Fatigue in Sport in Active Adults with Long COVID-19: An Observational Study.

Coscia, Francesco, Mancinelli, Rosa, Gigliotti, Paola Virginia et al.·Diagnostics (Basel, Switzerland)·2023

This study looked at how physical activity affected fatigue and other symptoms in people with Long COVID-19. Researchers compared people who stayed active with those who were sedentary and tracked their symptoms over 6 to 12 months. They found that people who remained physically active experienced a larger drop in fatigue over time compared to those who were inactive, though both groups still had muscle weakness and sleep problems.

SleepCognitive Impairment

E2 ModerateCohortPEM unclearLongitudinal

Investigating the factors associated with meaningful improvement on the SF-36-PFS and exploring the appropriateness of this measure for young people with ME/CFS accessing an NHS specialist service: a prospective cohort study.

Gaunt, Daisy, Brigden, Amberly, Metcalfe, Chris et al.·BMJ open·2023

This study followed 193 young people with ME/CFS at a UK NHS specialist service to see how many improved over 6-12 months and what factors predicted improvement. About 40% showed meaningful improvement at 6 months, rising to 54% at 12 months. Interestingly, young people who started with worse physical function scores were actually more likely to show improvement, but very few other patient characteristics predicted who would get better.

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 requiredCross-Sectional

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and fibromyalgia: PR3-versus MPO-ANCA-associated vasculitis, an exploratory cross-sectional study.

van Eeden, Charmaine, Mohazab, Naima, Redmond, Desiree et al.·Lancet regional health. Americas·2023

This study looked at fatigue in people with ANCA-vasculitis (a type of blood vessel inflammation) and found that over half met the diagnostic criteria for ME/CFS. The researchers discovered that the type of vasculitis matters: people with MPO-ANCA had fatigue patterns more similar to fibromyalgia, while those with PR3-ANCA had fatigue linked to inflammation markers. This suggests different types of vasculitis may cause fatigue through different biological mechanisms.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

[Implications of the quality of the doctor-patient relationship on health in adult ME/CFS patients. A qualitative public health study from a patien perspective].

Habermann-Horstmeier, Lotte, Horstmeier, Lukas M·MMW Fortschritte der Medizin·2023

This study surveyed 544 ME/CFS patients about their experiences with doctors. Most patients reported feeling unsupported, misunderstood, and dismissed—with doctors not recognizing ME/CFS as a real biological disease. These poor relationships with healthcare providers led to serious consequences: patients avoided doctors, lost trust in medicine, and some even experienced thoughts of suicide. The researchers conclude that doctors need to treat ME/CFS patients as experts in their own illness and develop better, patient-centered care approaches.

E2 ModerateCohortPEM unclearCross-Sectional

Circulating microRNA expression signatures accurately discriminate myalgic encephalomyelitis from fibromyalgia and comorbid conditions.

Nepotchatykh, Evguenia, Caraus, Iurie, Elremaly, Wesam et al.·Scientific reports·2023

Researchers studied tiny molecules called microRNAs in the blood to see if they could tell the difference between ME/CFS, fibromyalgia, and people who have both conditions. They found that each condition has a unique pattern of these microRNAs, like a biological fingerprint. Using these patterns, they created a computer model that could accurately identify which condition a person has, which could help with proper diagnosis.

Biomarkers

E2 ModerateCohortPEM not required

Health outcomes of sensory hypersensitivities in myalgic encephalomyelitis/chronic fatigue syndrome and multiple sclerosis.

Maeda, Kensei I, Islam, Mohammed F, Conroy, Karl E et al.·Psychology, health & medicine·2023

This study looked at how common sensitivity to light and sound are in people with ME/CFS compared to people with multiple sclerosis (MS). Researchers surveyed over 2,200 people and found that people with ME/CFS experience these sensitivities much more often than people with MS. People who had both light and sound sensitivity reported feeling worse overall than those without these sensitivities.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Distinguishing features of long COVID identified through immune profiling.

Klein, Jon, Wood, Jamie, Jaycox, Jillian R et al.·Nature·2023

Researchers studied 275 people with and without long COVID to understand what happens in the immune system. They found that people with long COVID have different patterns of immune cells and antibodies, including stronger responses to past viral infections like Epstein-Barr virus, and lower levels of the stress hormone cortisol. Using computer analysis, they identified specific immune markers that could help identify who has long COVID.

BiomarkersImmune System

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 ModerateBehavioralPEM not requiredCross-Sectional

High Perceived Stress and Low Self-Efficacy are Associated with Functional Somatic Disorders: The DanFunD Study.

Petersen, Marie Weinreich, Carstensen, Tina Birgitte Wisbech, Frostholm, Lisbeth et al.·Clinical epidemiology·2023

This study of over 9,600 Danish people examined whether stress and confidence in one's abilities are connected to functional somatic disorders—conditions like chronic fatigue, widespread pain, and irritable bowel syndrome where symptoms are real but don't have a clear physical cause. The researchers found that people with these conditions tend to feel more stressed and have lower confidence in their abilities compared to healthy people, though their stress levels were not necessarily higher than people with serious physical diseases.

E2 ModerateCohortPEM unclearObservational

Cognitive impairment in post-acute sequelae of COVID-19 and short duration myalgic encephalomyelitis patients is mediated by orthostatic hemodynamic changes.

Day, Heather, Yellman, Brayden, Hammer, Sarah et al.·Frontiers in neuroscience·2023

This study examined why people with ME/CFS and long COVID experience 'brain fog' and memory problems. Researchers tested how well people could think and remember before and after standing up quickly (which can make blood pressure drop). They found that people with these illnesses had more trouble thinking clearly after the standing test, and this was linked to unusual changes in their heart rate and blood pressure. The findings suggest that problems with blood flow to the brain during physical stress may be contributing to cognitive difficulties.

Autonomic Nervous SystemCognitive Impairment

E2 ModerateCohortPEM requiredCross-Sectional

Typing myalgic encephalomyelitis by infection at onset: A DecodeME study.

Bretherick, Andrew D, McGrath, Simon J, Devereux-Cooke, Andy et al.·NIHR open research·2023

This large study asked over 17,000 people with ME/CFS about their symptoms, when their illness started, and what health conditions they experience. The researchers found that ME/CFS is not one-size-fits-all: people whose ME/CFS began after an infection (like COVID-19 or glandular fever) reported different patterns of symptoms and other health problems compared to those whose illness started without a clear infection. The study also confirmed that women are more affected by ME/CFS than men, and discovered that women tend to have more additional health conditions alongside ME/CFS.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

A cross-sectional study exploring the relationship between symptoms of anxiety/depression and P50 sensory gating in adult patients diagnosed with chronic fatigue syndrome/myalgic encephalomyelitis.

Liu, Xinyi, Liu, Sitong, Ren, Runtao et al.·Frontiers in neuroscience·2023

This study looked at 249 people with ME/CFS to understand how anxiety and depression relate to a specific brain activity pattern called P50 sensory gating. Researchers used questionnaires to measure anxiety and depression, and brain scans (EEG) to measure how well the brain filters out repetitive sounds. They found that abnormal filtering of sounds was linked to anxiety, depression, and fatigue severity.

E2 ModerateCohortPEM not requiredLongitudinal

Three-Month Symptom Profiles Among Symptomatic Adults With Positive and Negative Severe Acute Respiratory Syndrome Coronavirus 2 Tests: A Prospective Cohort Study From the INSPIRE Group.

Spatz, Erica S, Gottlieb, Michael, Wisk, Lauren E et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·2023

This study followed adults who tested positive or negative for COVID-19 and tracked their symptoms over three months. At the three-month mark, people who had COVID-19 were much more likely to still have symptoms like fatigue, breathing problems, or muscle pain compared to those who tested negative. Importantly, symptoms of post-infectious syndromes (like unrefreshing sleep and fatigue) were common in both groups, suggesting these symptoms can occur even without COVID-19 infection.

Long COVID Overlap

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

Pattern of Post COVID Fatigue in Elderly Patients.

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

The relevance of pacing strategies in managing symptoms of post-COVID-19 syndrome.

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

The Conners Continuous Performance Test CPT3™: Is it a reliable marker to predict neurocognitive dysfunction in Myalgic encephalomyelitis/chronic fatigue syndrome?

Physical Activity Effects on Muscle Fatigue in Sport in Active Adults with Long COVID-19: An Observational Study.

Investigating the factors associated with meaningful improvement on the SF-36-PFS and exploring the appropriateness of this measure for young people with ME/CFS accessing an NHS specialist service: a prospective cohort study.

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

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and fibromyalgia: PR3-versus MPO-ANCA-associated vasculitis, an exploratory cross-sectional study.

[Implications of the quality of the doctor-patient relationship on health in adult ME/CFS patients. A qualitative public health study from a patien perspective].

Circulating microRNA expression signatures accurately discriminate myalgic encephalomyelitis from fibromyalgia and comorbid conditions.

Health outcomes of sensory hypersensitivities in myalgic encephalomyelitis/chronic fatigue syndrome and multiple sclerosis.

Distinguishing features of long COVID identified through immune profiling.

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

High Perceived Stress and Low Self-Efficacy are Associated with Functional Somatic Disorders: The DanFunD Study.

Cognitive impairment in post-acute sequelae of COVID-19 and short duration myalgic encephalomyelitis patients is mediated by orthostatic hemodynamic changes.

Typing myalgic encephalomyelitis by infection at onset: A DecodeME study.

A cross-sectional study exploring the relationship between symptoms of anxiety/depression and P50 sensory gating in adult patients diagnosed with chronic fatigue syndrome/myalgic encephalomyelitis.

Three-Month Symptom Profiles Among Symptomatic Adults With Positive and Negative Severe Acute Respiratory Syndrome Coronavirus 2 Tests: A Prospective Cohort Study From the INSPIRE Group.

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.

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