ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2782 studies

581–600 of 2,782 studies

E2 ModerateBehavioralPEM not requiredLongitudinal

Generalized Worry in Patients With Chronic Fatigue Syndrome Following Cognitive Behavioral Therapy: A Prospective Cohort Study in Secondary Care.

Kalfas, Michail, Smakowski, Abigail, Hirsch, Colette et al.·Behavior therapy·2022

This study looked at worry in nearly 500 people with ME/CFS who received a talking therapy called cognitive behavioral therapy (CBT). About 7 in 10 patients had significant worry alongside their fatigue. After CBT, patients reported notably less worry, and this improvement stayed stable months later. People who worried severely at the start also experienced worse fatigue and had more difficulty with work and social activities.

E2 ModerateCohortPEM unclearCross-Sectional

Lowered Quality of Life in Long COVID Is Predicted by Affective Symptoms, Chronic Fatigue Syndrome, Inflammation and Neuroimmunotoxic Pathways.

Maes, Michael, Al-Rubaye, Haneen Tahseen, Almulla, Abbas F et al.·International journal of environmental research and public health·2022

This study found that Long COVID patients have significantly lower quality of life compared to healthy people, and this decline is mostly explained by three factors: mood and pain-related symptoms (like depression, anxiety, and fatigue), signs of ongoing inflammation in the body, and problems with how the body processes calcium. The severity of the initial infection—measured by high fever and low oxygen levels—also plays a role by triggering these inflammatory and immune problems that persist afterward.

NeuroinflammationImmune System

E2 ModerateCohortPEM requiredObservational

Factors Influencing the Prognosis of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Ghali, Alaa, Lacout, Carole, Fortrat, Jacques-Olivier et al.·Diagnostics (Basel, Switzerland)·2022

This study looked at 168 ME/CFS patients to understand what factors help people recover or significantly improve. The research found that only about 13% of patients experienced recovery or substantial improvement over time. Interestingly, patients who were older when they first got sick were more likely to improve, and people who received a diagnosis sooner (without long delays) also had better outcomes. The study confirms that ME/CFS is generally a serious condition with poor prognosis, but suggests that improvement is possible at any age.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

The Relationship between Physical Activity and Long COVID: A Cross-Sectional Study.

Wright, Jack, Astill, Sarah L, Sivan, Manoj·International journal of environmental research and public health·2022

This study asked 477 people with Long COVID about their physical activity levels before and after illness, and how exercise affected their symptoms. Participants were much less active after getting Long COVID and needed more help with daily tasks. Most people (about 75%) reported that physical activity made their symptoms worse, while only about 1% said it improved them.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Post-COVID-19 Syndrome: Retinal Microcirculation as a Potential Marker for Chronic Fatigue.

Schlick, Sarah, Lucio, Marianna, Wallukat, Gerd et al.·International journal of molecular sciences·2022

Researchers studied whether tiny blood vessels in the eye could be a measurable sign of fatigue in people with long COVID. Using a special imaging technique to look at blood vessels in the retina (back of the eye), they found that people with long COVID—especially women—had reduced blood flow in these tiny vessels compared to healthy people. Those with long COVID who reported severe fatigue had even lower blood vessel density than those with milder fatigue, suggesting the eye scan might objectively confirm what patients report feeling.

Biomarkers

E2 ModerateCohortPEM unclearCross-Sectional

Saliva antibody-fingerprint of reactivated latent viruses after mild/asymptomatic COVID-19 is unique in patients with myalgic-encephalomyelitis/chronic fatigue syndrome.

Apostolou, Eirini, Rizwan, Muhammad, Moustardas, Petros et al.·Frontiers in immunology·2022

This study found that people with ME/CFS have a different immune response to COVID-19 compared to healthy people, even when the COVID infection is mild. Specifically, the researchers discovered that after COVID-19, dormant viruses (like EBV and others) reactivate more strongly in people with ME/CFS, as shown by antibody patterns in saliva. This suggests that COVID-19 may trigger hidden virus reactivation that could contribute to fatigue symptoms in ME/CFS patients.

Immune System

E2 ModerateCohortPEM unclearCase-Control

Orthostatic Intolerance in Long-Haul COVID after SARS-CoV-2: A Case-Control Comparison with Post-EBV and Insidious-Onset Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients.

van Campen, C Linda M C, Visser, Frans C·Healthcare (Basel, Switzerland)·2022

This study compared patients with long-haul COVID to two groups of ME/CFS patients (those who got sick after Epstein-Barr virus infection and those who became ill gradually) to understand a common symptom called orthostatic intolerance—dizziness or fainting when standing up. Researchers found that long-haul COVID patients had similar symptoms and physical responses to standing as ME/CFS patients, and all three groups showed comparable problems with blood flow and heart function during the standing test. The findings suggest that long-haul COVID and ME/CFS may be essentially the same underlying condition.

Autonomic Nervous System

E2 ModerateCohortPEM unclearObservational

Activity monitoring and patient-reported outcome measures in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients.

Rekeland, Ingrid G, Sørland, Kari, Bruland, Ove et al.·PloS one·2022

This study tracked 27 ME/CFS patients for six months using Fitbit activity monitors and questionnaires to understand how symptoms vary day-to-day and whether activity data matches what patients report. Researchers found that people with milder disease had larger swings in their activity levels week-to-week, while those with severe disease stayed consistently low. Activity monitoring proved feasible and useful as a tool alongside patient surveys.

E2 ModerateCohortPEM not requiredObservational

The incidence and characteristics of chronic pain and fatigue after 12 months later admitting with COVID-19; The Post- COVID 19 syndrome.

Janbazi, Lobaneh, Kazemian, Alireza, Mansouri, Kourosh et al.·American journal of physical medicine & rehabilitation·2022

Researchers followed 157 people who were hospitalized with COVID-19 and checked on them 12 months later. They found that about 27% still had chronic fatigue and muscle weakness, and about 15% experienced chronic pain, mostly in the lower back and legs. Women were more likely than men to report these symptoms, and many patients were only using pain medications rather than receiving rehabilitation or mental health support.

Pain and Sensitization

E2 ModerateCohortPEM not requiredObservational

Endometriosis: A Retrospective Analysis of Clinical Data from a Cohort of 4,083 Patients, With Focus on Symptoms.

Signorile, Pietro G, Cassano, Maria, Viceconte, Rosa et al.·In vivo (Athens, Greece)·2022

This study looked at health records from over 4,000 women with endometriosis (a painful condition where tissue grows outside the uterus) to understand which symptoms are most common. The researchers found that chronic fatigue, painful intercourse, and bowel problems are major symptoms of endometriosis, and interestingly, symptoms tend to peak in women aged 25-44 years before declining. The study suggests that having children may help reduce fatigue in women with endometriosis.

E2 ModeratePEM unclearRegistry-Resource

The Facilitation of Clinical and Therapeutic Discoveries in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Related Diseases: Protocol for the You + ME Registry Research Platform.

Ramiller, Allison, Mudie, Kathleen, Seibert, Elle et al.·JMIR research protocols·2022

Researchers created a registry called 'You + ME' to collect health information from thousands of people with ME/CFS, long COVID, and healthy volunteers over time. By gathering this large amount of data in one place, researchers hope to better understand why people get sick differently and develop new treatments. As of September 2021, over 4,200 people had joined, with most participants finding the registry helpful and likely to recommend it to others.

E2 ModerateCohortPEM unclearObservational

The Impact of COVID Vaccination on Symptoms of Long COVID: An International Survey of People with Lived Experience of Long COVID.

Strain, William David, Sherwood, Ondine, Banerjee, Amitava et al.·Vaccines·2022

This survey asked 812 people with long COVID about how COVID-19 vaccination affected their symptoms. Overall, 58% reported feeling better after vaccination, 18% felt worse, and the rest noticed no change. People who received mRNA vaccines (like Pfizer and Moderna) tended to see more improvement than those who received other types of vaccines. However, responses varied greatly from person to person.

Immune System

E2 ModerateCohortPEM not requiredLongitudinal

Altered Effective Connectivity of Resting-State Networks by Tai Chi Chuan in Chronic Fatigue Syndrome Patients: A Multivariate Granger Causality Study.

Li, Yuanyuan, Wu, Kang, Hu, Xiaojie et al.·Frontiers in neurology·2022

This study looked at how a traditional Chinese exercise called Tai Chi Chuan affects the brain in ME/CFS patients. Using brain imaging, researchers found that ME/CFS patients had weaker communication between two important brain networks compared to healthy people. After just one month of Tai Chi Chuan training, this brain communication improved, and patients reported better quality of life, especially with less pain and better physical function.

E2 ModerateCohortPEM unclearCross-Sectional

Autoimmune gene expression profiling of fingerstick whole blood in Chronic Fatigue Syndrome.

Wang, Zheng, Waldman, Michelle F, Basavanhally, Tara J et al.·Journal of translational medicine·2022

Researchers tested blood samples from 166 ME/CFS patients and 83 healthy people to look for immune system clues that might explain the disease. They found that six specific genes related to immune function were more active in patients with severe, bedridden ME/CFS compared to those with milder disease. The study suggests these genes could potentially be used as biomarkers to identify how severe someone's ME/CFS is and might point toward new treatments.

BiomarkersImmune System

E2 ModerateCohortPEM unclearCross-Sectional

Long-term sequelae of COVID-19 (myalgic encephalomyelitis): An international cross-sectional study.

Shaheen, Nour, Shaheen, Ahmed·Medicine·2022

This study examined how COVID-19 affects people's health long after the initial infection, including whether some people develop ME/CFS (myalgic encephalomyelitis) as a result. Researchers planned to survey 20,000 people worldwide about their ongoing symptoms weeks to months after COVID-19 infection, using detailed questionnaires to capture a wide range of both common and unusual long-term effects. The goal was to understand who develops long-term problems and whether COVID-19 can trigger ME/CFS in previously healthy people.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredObservational

A 2-day cardiopulmonary exercise test in chronic fatigue syndrome patients who were exposed to humidifier disinfectants.

Leem, Jong-Han, Jeon, Hyoung-Eun, Nam, Hun et al.·Environmental analysis, health and toxicology·2022

This study tested whether a special two-day exercise test could detect post-exertional malaise (PEM)—the worsening of symptoms after physical activity—in people with ME/CFS who had been exposed to humidifier disinfectants. The researchers had 29 participants complete an exercise test, rest for 24 hours, then repeat it. They found that performance noticeably declined on the second day, showing that PEM is real and measurable.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Findings from a survey about hidradenitis suppurativa in the Netherlands.

The British journal of dermatology·2022

Hidradenitis suppurativa (HS) is a painful skin condition that causes recurrent boils, drainage, and scarring in areas like armpits and groin. This Dutch study surveyed over 167,000 people and found that HS is more common than previously thought (2% rather than 1%), and that people with HS often have other conditions including chronic fatigue syndrome, fibromyalgia, and depression. The study also found that many people with HS have not yet been diagnosed or treated.

E2 ModerateCohortPEM not requiredCross-Sectional

Exposure-response relationship between K. brevis blooms and reporting of upper respiratory and neurotoxin-associated symptoms.

Abdullah, L, Ferguson, S, Niedospial, D et al.·Harmful algae·2022

Researchers studied whether harmful algal blooms caused by Karenia brevis (a type of seaweed) in Florida's Gulf waters trigger respiratory symptoms, headaches, and nerve-related illness symptoms in people living nearby. They surveyed 258 residents in five coastal counties and found a clear link: when blooms were stronger, more people reported these symptoms. People with previous diagnoses of migraines, chronic fatigue syndrome, or memory problems were more likely to report these symptoms during blooms.

E2 ModerateCohortPEM not requiredCross-Sectional

Post-acute sequelae of SARS-CoV-2 infection: relationship of central nervous system manifestations with physical disability and systemic inflammation.

Busatto, Geraldo F, de Araujo, Adriana Ladeira, Castaldelli-Maia, João Mauricio et al.·Psychological medicine·2022

Researchers studied 749 people who had been hospitalized with COVID-19 and assessed them 6-11 months later. They found that 30 different symptoms—including fatigue, brain fog, depression, and anxiety—tend to occur together as part of one underlying condition. People with more severe symptoms also showed signs of ongoing inflammation in their blood and had greater physical disability, suggesting a real biological basis for their illness.

Cognitive Impairment

E2 ModerateCohortPEM unclearCase-Control

Genetic and epigenetic regulation of Catechol-O-methyltransferase in relation to inflammation in chronic fatigue syndrome and Fibromyalgia.

Polli, Andrea, Hendrix, Jolien, Ickmans, Kelly et al.·Journal of translational medicine·2022

This study looked at how genes and chemical changes in DNA affect a protein called COMT, which plays a role in pain and inflammation in ME/CFS and fibromyalgia. Researchers compared 28 patients with these conditions to 26 healthy people and measured pain sensitivity, genetic variants, and immune markers. They found that certain genetic patterns and DNA changes were linked to symptoms and immune responses, suggesting that how our genes are "switched on or off" may contribute to these conditions.

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Generalized Worry in Patients With Chronic Fatigue Syndrome Following Cognitive Behavioral Therapy: A Prospective Cohort Study in Secondary Care.

Lowered Quality of Life in Long COVID Is Predicted by Affective Symptoms, Chronic Fatigue Syndrome, Inflammation and Neuroimmunotoxic Pathways.

Factors Influencing the Prognosis of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

The Relationship between Physical Activity and Long COVID: A Cross-Sectional Study.

Post-COVID-19 Syndrome: Retinal Microcirculation as a Potential Marker for Chronic Fatigue.

Saliva antibody-fingerprint of reactivated latent viruses after mild/asymptomatic COVID-19 is unique in patients with myalgic-encephalomyelitis/chronic fatigue syndrome.

Orthostatic Intolerance in Long-Haul COVID after SARS-CoV-2: A Case-Control Comparison with Post-EBV and Insidious-Onset Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients.

Activity monitoring and patient-reported outcome measures in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome patients.

The incidence and characteristics of chronic pain and fatigue after 12 months later admitting with COVID-19; The Post- COVID 19 syndrome.

Endometriosis: A Retrospective Analysis of Clinical Data from a Cohort of 4,083 Patients, With Focus on Symptoms.

The Facilitation of Clinical and Therapeutic Discoveries in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Related Diseases: Protocol for the You + ME Registry Research Platform.

The Impact of COVID Vaccination on Symptoms of Long COVID: An International Survey of People with Lived Experience of Long COVID.

Altered Effective Connectivity of Resting-State Networks by Tai Chi Chuan in Chronic Fatigue Syndrome Patients: A Multivariate Granger Causality Study.

Autoimmune gene expression profiling of fingerstick whole blood in Chronic Fatigue Syndrome.

Long-term sequelae of COVID-19 (myalgic encephalomyelitis): An international cross-sectional study.

A 2-day cardiopulmonary exercise test in chronic fatigue syndrome patients who were exposed to humidifier disinfectants.

Findings from a survey about hidradenitis suppurativa in the Netherlands.

Exposure-response relationship between K. brevis blooms and reporting of upper respiratory and neurotoxin-associated symptoms.

Post-acute sequelae of SARS-CoV-2 infection: relationship of central nervous system manifestations with physical disability and systemic inflammation.

Genetic and epigenetic regulation of Catechol-O-methyltransferase in relation to inflammation in chronic fatigue syndrome and Fibromyalgia.

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