ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2807 studies

261–280 of 2,807 studies

E2 ModerateCohortPEM unclearCross-Sectional

A Signal for Voice and Speech Abnormalities in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Grach, Stephanie L, Seltzer, Jaime, Orbelo, Diana M·Journal of clinical medicine·2025

This study explored whether people with ME/CFS experience changes in their voice or speech. Researchers surveyed 685 people with ME/CFS and reviewed open-ended responses from 302 participants. About 9% of respondents mentioned voice or speech changes when describing their disease experience, suggesting this is a real symptom that deserves further attention.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Abnormal T-Cell activation and cytotoxic T-Cell frequency discriminate symptom severity in myalgic encephalomyelitis/chronic fatigue syndrome.

Lee, Ji-Sook, Lacerda, Eliana, Kingdon, Caroline et al.·Journal of translational medicine·2025

This study compared immune system profiles in 96 ME/CFS patients with either mild/moderate or severe disease. Researchers found that people with severe ME/CFS had more activated immune cells and higher levels of inflammatory chemicals, while those with milder disease showed different patterns suggesting their bodies were responding to chronic viral infection. These findings suggest that mild and severe ME/CFS may involve different underlying immune problems, which could eventually help doctors predict disease severity and develop targeted treatments.

Immune System

E2 ModerateCohortPEM unclearCase-Control

Epstein-Barr virus (EBV) reactivation in post COVID-19.

Shady, Eslam Farid Abu, Ghallab, Abdelhakim Fouad, Shaker, Doaa Abdullah et al.·Auris, nasus, larynx·2025

This study looked at whether a virus called Epstein-Barr virus (EBV) wakes up again in people who have prolonged COVID symptoms like fatigue. Researchers compared 140 people with ongoing COVID fatigue to 80 people who fully recovered from COVID. They found that EBV was reactivated in about 29% of people with persistent fatigue compared to 11% of those who recovered, suggesting EBV reactivation might play a role in long COVID.

Immune SystemPost-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Longitudinal Progression of Patients with Long COVID Treated in a Post-COVID Clinic: A Cross-Sectional Survey.

Hurt, Ryan T, Yadav, Siddhant, Schroeder, Darrell R et al.·Journal of primary care & community health·2024

This study surveyed over 500 Long COVID patients who received care at a specialized clinic about 2 years after their initial infection. While most patients reported that their symptoms improved compared to their first visit, only 4.5% felt they had fully recovered. Some treatments like low-dose naltrexone, vagal nerve stimulation, and fisetin were rated as helpful by a majority of patients who tried them.

Interventions

E2 ModerateCohortPEM unclearCase-Control

A case-control study of reaction time deficits in a 3D virtual reality in patients with Post-COVID syndrome.

Güttes, Moritz, Lucio, Marianna, Skornia, Adam et al.·Scientific reports·2024

Researchers tested whether people with Post-COVID syndrome have slower reaction times when responding to visual stimuli shown in virtual reality glasses. They found that Post-COVID patients were indeed slower and less accurate at this task compared to healthy controls, suggesting this test might be a useful tool for identifying Post-COVID cognitive problems in the future.

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 unclearCross-Sectional

Prevalence and determinants of post-acute sequelae after SARS-CoV-2 infection (Long COVID) among adults in Mexico during 2022: a retrospective analysis of nationally representative data.

Bello-Chavolla, Omar Yaxmehen, Fermín-Martínez, Carlos A, Ramírez-García, Daniel et al.·Lancet regional health. Americas·2024

This study looked at how many adults in Mexico experienced long-lasting symptoms after COVID-19 infection in 2022. Researchers found that about 1 in 5 people who had COVID-19 reported ongoing problems like fatigue, muscle pain, brain fog, and loss of taste or smell. The study showed that people who caught COVID-19 multiple times, had depression, or lived in poorer areas were more likely to develop these long-term symptoms, while vaccination and infection with newer variants reduced risk.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Illness presentation and quality of life in myalgic encephalomyelitis/chronic fatigue syndrome and post COVID-19 condition: a pilot Australian cross-sectional study.

Weigel, Breanna, Eaton-Fitch, Natalie, Thapaliya, Kiran et al.·Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation·2024

This study compared symptoms and quality of life in people with ME/CFS, people with long COVID, and healthy controls in Australia. Both ME/CFS and long COVID patients experienced similar debilitating symptoms affecting memory, sleep, and physical function, and both groups had much lower quality of life scores than healthy people. The findings suggest that ME/CFS and long COVID are similarly serious illnesses that require comprehensive medical care.

Diagnostics

E2 ModerateCohortPEM not requiredCase-Control

Increased risk of chronic fatigue syndrome following pneumonia: A population-based Cohort study.

Hsu, Han-Jen, Chang, Hsun, Lin, Cheng-Li et al.·Journal of infection and public health·2024

This study found that people who have pneumonia are about 1.4 times more likely to develop ME/CFS compared to people who don't have pneumonia. The risk was higher for certain types of bacterial and viral infections, including specific bacteria like Pseudomonas and Streptococcus pneumoniae, as well as influenza virus. The researchers used health records from 2 million adults in Taiwan to track whether pneumonia patients developed ME/CFS over time.

E2 ModerateCohortPEM not requiredCross-Sectional

Service users' and parents/carers' experiences of a paediatric chronic fatigue service: A service evaluation.

Hartley, Gemma, Purrington, Jack·Chronic illness·2024

This study asked children with chronic fatigue syndrome (ME/CFS) and their parents about their experiences at a specialist clinic that treats young people with the condition. Most families felt the service helped them understand their illness better, learn useful strategies to manage their symptoms, and gradually increase their activity levels safely. However, some families had trouble accessing the service due to its location, appointment scheduling, and difficulty contacting staff.

E2 ModerateCohortPEM requiredCross-Sectional

Impact of COVID-19 on myalgic encephalomyelitis/chronic fatigue syndrome-like illness prevalence: A cross-sectional survey.

Wood, Mariah S, Halmer, Nicole, Bertolli, Jeanne et al.·PloS one·2024

This study found that about 1.67% of adults in a large California health system have ME/CFS-like illness. While COVID-19 can trigger ME/CFS in some people, only about 14% of those with ME/CFS-like illness developed it after having COVID-19. People with ME/CFS-like illness reported significant difficulties with physical activities, work, relationships, and mental health compared to those without the condition.

E2 ModerateCohortPEM unclearCross-Sectional

Long COVID diagnostic with differentiation from chronic lyme disease using machine learning and cytokine hubs.

Patterson, Bruce K, Guevara-Coto, Jose, Mora, Javier et al.·Scientific reports·2024

Researchers developed a computer-based test using blood measurements called cytokines to accurately identify long COVID (also called PASC) in patients. The test was able to correctly identify long COVID in 97% of cases and correctly rule it out in 90% of cases when tested on a new group of people. Importantly, the test could also distinguish long COVID from chronic Lyme disease, which can cause similar symptoms, helping doctors diagnose the right condition.

Immune System

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 ModerateBehavioralPEM not requiredCross-Sectional

The presence of attentional and interpretation biases in patients with severe MS-related fatigue.

de Gier, Marieke, Oosterman, Joukje M, Hughes, Alicia M et al.·British journal of health psychology·2024

This study looked at whether people with severe fatigue from MS or ME/CFS tend to notice fatigue-related information more readily or interpret unclear physical symptoms in a threatening way compared to healthy people. Researchers found that both MS and ME/CFS patients interpreted ambiguous body sensations as more threatening than healthy controls did, though there was no difference in how they paid attention to fatigue-related words. The way patients interpreted symptoms was linked to how they mentally responded to their symptoms.

Cognitive Impairment

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 unclearObservational

Management of severe ME/CFS in children and young people in the UK: a British Paediatric Surveillance Unit study.

Royston, Alexander Peter, Burge, Sarah, Idini, Ilaria et al.·BMJ paediatrics open·2024

This UK study looked at how children and young people with severe ME/CFS are diagnosed and treated. Researchers found that many young people with suspected severe ME/CFS were not getting complete medical investigations to rule out other conditions, and most were not being referred to specialist services. The care these young people received varied greatly, and some didn't receive any help at all.

E2 ModerateBehavioralPEM not requiredCase-Control

Psychological flexibility in somatic symptom and related disorders: A case control study.

Selker, René J D M, Koppert, Tim Y, Houtveen, Jan H et al.·Journal of psychiatric research·2024

This study looked at how well people can handle difficult thoughts and feelings without being overwhelmed by them—a skill called psychological flexibility. Researchers compared 154 people with somatic symptom disorder (SSD, where people are very distressed by physical symptoms) to nearly 2,000 people with other conditions like ME/CFS or no illness. People with SSD had much lower psychological flexibility than both other groups, and this lower flexibility was linked to worse mental health.

E2 ModerateCohortPEM unclearObservational

Low-dose Naltrexone Improves post-COVID-19 condition Symptoms.

Tamariz, Leonardo, Bast, Elizabeth, Klimas, Nancy et al.·Clinical therapeutics·2024

This study looked at whether treatments used for ME/CFS could help people with long COVID. Researchers reviewed records from 108 patients who tried different treatments including low-dose naltrexone, amitriptyline, duloxetine, and physical therapy. They found that patients taking low-dose naltrexone were about 5 times more likely to improve compared to those doing physical therapy alone, with improvements in both fatigue and pain.

Pain and SensitizationCognitive Impairment

E2 ModerateCohortPEM unclearObservational

Resonant breathing improves self-reported symptoms and wellbeing in people with Long COVID.

Polizzi, Jessica, Tosto-Mancuso, Jenna, Tabacof, Laura et al.·Frontiers in rehabilitation sciences·2024

This study looked at whether slow, controlled breathing (called resonant breathing) could help people with Long COVID feel better. Ninety-nine people with Long COVID tried a resonant breathing program and reported their symptoms before and after. Most people said they felt better overall, especially in areas like stress control, focus, breathing ability, and sleep quality.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Systemic antibody responses against gut microbiota flagellins implicate shared and divergent immune reactivity in Crohn's disease and chronic fatigue syndrome.

Bourgonje, Arno R, Hörstke, Nicolai V, Fehringer, Michaela et al.·Microbiome·2024

This study looked at immune responses in ME/CFS and Crohn's disease patients by measuring antibodies against proteins from gut bacteria called flagellins. Researchers found that both patient groups had elevated antibodies against these bacterial proteins, but the pattern of where these antibodies attached differed between the two diseases. These antibody patterns could potentially help doctors diagnose ME/CFS and understand how the immune system may be responding abnormally to gut bacteria.

Gut MicrobiomeImmune System

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Evidence Atlas

Evidence browser

A Signal for Voice and Speech Abnormalities in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Abnormal T-Cell activation and cytotoxic T-Cell frequency discriminate symptom severity in myalgic encephalomyelitis/chronic fatigue syndrome.

Epstein-Barr virus (EBV) reactivation in post COVID-19.

Longitudinal Progression of Patients with Long COVID Treated in a Post-COVID Clinic: A Cross-Sectional Survey.

A case-control study of reaction time deficits in a 3D virtual reality in patients with Post-COVID 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.

Prevalence and determinants of post-acute sequelae after SARS-CoV-2 infection (Long COVID) among adults in Mexico during 2022: a retrospective analysis of nationally representative data.

Illness presentation and quality of life in myalgic encephalomyelitis/chronic fatigue syndrome and post COVID-19 condition: a pilot Australian cross-sectional study.

Increased risk of chronic fatigue syndrome following pneumonia: A population-based Cohort study.

Service users' and parents/carers' experiences of a paediatric chronic fatigue service: A service evaluation.

Impact of COVID-19 on myalgic encephalomyelitis/chronic fatigue syndrome-like illness prevalence: A cross-sectional survey.

Long COVID diagnostic with differentiation from chronic lyme disease using machine learning and cytokine hubs.

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.

The presence of attentional and interpretation biases in patients with severe MS-related fatigue.

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

Management of severe ME/CFS in children and young people in the UK: a British Paediatric Surveillance Unit study.

Psychological flexibility in somatic symptom and related disorders: A case control study.

Low-dose Naltrexone Improves post-COVID-19 condition Symptoms.

Resonant breathing improves self-reported symptoms and wellbeing in people with Long COVID.

Systemic antibody responses against gut microbiota flagellins implicate shared and divergent immune reactivity in Crohn's disease and chronic fatigue syndrome.

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