ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2061–2080 of 6,209 studies

E2 ModerateCohortPEM unclearCross-Sectional

Prevalence of and risk factors for severe cognitive and sleep symptoms in ME/CFS and MS.

Jain, Vageesh, Arunkumar, Amit, Kingdon, Caroline et al.·BMC neurology·2017

This study compared cognitive problems (like trouble concentrating and memory issues) and sleep difficulties in people with ME/CFS and people with MS. Researchers found that cognitive and sleep problems were much more common in ME/CFS patients—98% reported trouble concentrating, and 55% reported severe unrefreshing sleep. The study also identified that ME/CFS patients who were older, current smokers, or had lower incomes were more likely to experience severe symptoms.

SleepCognitive Impairment

E2 ModerateCohortPEM unclearCase-Control

Multimodal and simultaneous assessments of brain and spinal fluid abnormalities in chronic fatigue syndrome and the effects of psychiatric comorbidity.

Natelson, Benjamin H, Mao, Xiangling, Stegner, Aaron J et al.·Journal of the neurological sciences·2017

This study compared brain and spinal fluid measurements in people with ME/CFS and healthy controls to understand what physical changes occur in the condition. Researchers found that ME/CFS patients had lower levels of a protective brain chemical (glutathione), reduced blood flow to the brain, higher levels of lactate (a sign of energy problems), and more abnormalities in spinal fluid compared to healthy people. Importantly, these differences were the same whether or not ME/CFS patients also had depression or anxiety, suggesting psychiatric conditions are not making the disease worse.

Biomarkers

E2 ModerateCohortPEM requiredCross-Sectional

Clinical Criteria Versus a Possible Research Case Definition in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis.

Jason, Leonard A, McManimen, Stephanie, Sunnquist, Madison et al.·Fatigue : biomedicine, health & behavior·2017

This study compared different ways of defining ME/CFS to see which one best identifies the sickest patients. Researchers looked at over 1,000 patients from multiple countries and found that using stricter criteria—specifically focusing on people who are homebound and meet core ME/CFS symptoms—identified a group with more severe symptoms and greater disability than the broader clinical definition. The researchers suggest that having a clear, standardized research definition would help scientists compare patients more fairly across different studies.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Comorbidity in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: A Nationwide Population-Based Cohort Study.

Castro-Marrero, Jesús, Faro, Mónica, Aliste, Luisa et al.·Psychosomatics·2017

This study looked at 1,757 people with ME/CFS in Spain to understand what other health conditions they commonly experience alongside their ME/CFS. Researchers found that more than 80% of patients had at least one additional condition, such as fibromyalgia, thyroid problems, vitamin D deficiency, or ligament issues. The study identified five different groups of ME/CFS patients based on their comorbidities, with some groups experiencing significantly worse fatigue and quality of life than others.

E2 ModerateCohortPEM unclearObservational

From good health to illness with post-infectious fatigue syndrome: a qualitative study of adults' experiences of the illness trajectory.

Stormorken, Eva, Jason, Leonard A, Kirkevold, Marit·BMC family practice·2017

This study followed 26 adults in Norway who developed severe fatigue and other symptoms after a water contamination outbreak caused by a parasite. Researchers interviewed these patients about how their illness developed and affected their daily lives. Everyone described similar patterns: getting worse over time, reaching a lowest point, then gradually improving—but none returned to their pre-illness health, and most had to stop working or studying.

Cognitive Impairment

E2 ModerateDiagnosticPEM not requiredMethods-Paper

Establishing Clinically Relevant Severity Levels for the Central Sensitization Inventory.

Neblett, Randy, Hartzell, Meredith M, Mayer, Tom G et al.·Pain practice : the official journal of World Institute of Pain·2017

Researchers created and tested a scoring system called the Central Sensitization Inventory (CSI) to help doctors identify when someone's symptoms may be caused by their nervous system being overly sensitive to pain signals. The study divided CSI scores into five levels—from subclinical to extreme—and confirmed that higher scores are associated with having more chronic conditions like fibromyalgia and ME/CFS, as well as higher levels of depression, sleep problems, and disability.

Pain and Sensitization

E2 ModerateBehavioralPEM not requiredLongitudinal

Do changes in illness perceptions, physical activity, and behavioural regulation influence fatigue severity and health-related outcomes in CFS patients?

De Gucht, V, Garcia, F K, den Engelsman, M et al.·Journal of psychosomatic research·2017

This study followed 144 CFS patients over one year to understand how their beliefs about their illness and their activity patterns affected their fatigue and overall health. Researchers found that patients who increasingly believed their illness had serious consequences and who used an all-or-nothing approach to activity (doing too much then crashing) tended to have worse fatigue. Illness beliefs also affected physical symptoms and mood, while activity patterns influenced both fatigue and physical functioning.

E2 ModerateCohortPEM requiredCross-Sectional

Post-Exertional Malaise in Patients with ME and CFS with Comorbid Fibromyalgia.

McManimen, Stephanie L, Jason, Leonard A·SRL neurology & neurosurgery·2017

This study looked at how having fibromyalgia (FM) alongside ME/CFS affects post-exertional malaise (PEM)—the worsening of symptoms after physical or mental activity. Researchers surveyed people online about their PEM symptoms and found that those with both conditions experienced more severe and frequent PEM symptoms than those with ME/CFS alone, particularly affecting muscle pain and overall fatigue. The findings suggest that having fibromyalgia as an additional diagnosis makes ME/CFS symptoms significantly worse.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Sleep Quality in Adolescents With Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME).

Josev, Elisha K, Jackson, Melinda L, Bei, Bei et al.·Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine·2017

This study examined sleep problems in teenagers with ME/CFS compared to healthy teenagers. Researchers found that teens with ME/CFS took longer to fall asleep, spent more total time in bed, slept longer overall, woke up later, and reported feeling their sleep was of poorer quality. Anxiety levels were also higher in the ME/CFS group and were connected to worse sleep quality in both groups.

Sleep

E2 ModerateCohortPEM unclearCross-Sectional

Medial prefrontal cortex deficits correlate with unrefreshing sleep in patients with chronic fatigue syndrome.

Shan, Zack Y, Kwiatek, Richard, Burnet, Richard et al.·NMR in biomedicine·2017

This study found that ME/CFS patients with the worst sleep quality had specific structural differences in a brain region called the medial prefrontal cortex compared to healthy people. The researchers used MRI brain scans to measure brain tissue and found that the brain tissue in this area appeared different in ME/CFS patients, especially those reporting unrefreshing sleep. This is important because it provides biological evidence that unrefreshing sleep in ME/CFS is a real physical problem, not just a patient's perception.

E2 ModerateBehavioralPEM not requiredLongitudinal

Long-term follow-up after cognitive behaviour therapy for chronic fatigue syndrome.

Janse, Anthonie, Nikolaus, Stephanie, Wiborg, Jan F et al.·Journal of psychosomatic research·2017

This study followed 511 people for up to 10 years after they completed cognitive behaviour therapy (CBT) for ME/CFS. While about 70% of people maintained improved physical function, fatigue levels increased somewhat over time, and some people experienced a return of severe fatigue and activity limitations. The results suggest CBT can help many people in the long term, but not everyone stays better.

Interventions

E2 ModerateCohortPEM not requiredCross-Sectional

Clinically proven mtDNA mutations are not common in those with chronic fatigue syndrome.

Schoeman, Elizna M, Van Der Westhuizen, Francois H, Erasmus, Elardus et al.·BMC medical genetics·2017

This study examined the DNA inside the energy-producing parts of cells (mitochondria) in 93 ME/CFS patients from the UK and South Africa. The researchers looked for specific mutations that are known to cause mitochondrial disease. They found that these known harmful mutations were not present in the ME/CFS patients studied, suggesting that ME/CFS is not caused by these well-established mitochondrial mutations.

Energy Metabolism

E2 ModerateDiagnosticPEM not requiredMethods-Paper

The assessment of fatigue: Psychometric qualities and norms for the Checklist individual strength.

Worm-Smeitink, M, Gielissen, M, Bloot, L et al.·Journal of psychosomatic research·2017

This study tested a questionnaire called the Checklist Individual Strength (CIS) that measures different types of fatigue, including how tired people feel, difficulty concentrating, lack of motivation, and reduced activity levels. Researchers gave this questionnaire to nearly 2,300 healthy people and over 5,000 patients with chronic fatigue to see if it accurately identifies severe fatigue. They found the CIS works well for measuring fatigue and recommended adjusting the score that indicates 'severe fatigue' from 35 to 40 points for ME/CFS research.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

An assessment of fatigue in patients with postural orthostatic tachycardia syndrome.

Wise, Shelby, Ross, Amanda, Brown, Abigail et al.·Journal of health psychology·2017

This study looked at fatigue in people with POTS (postural orthostatic tachycardia syndrome), a condition that shares many symptoms with ME/CFS. Researchers asked 138 young people with POTS to describe their fatigue and brain fog using questionnaires. They found that fatigue comes in multiple forms and that people with POTS fall into two groups: those with mild symptoms and those with severe symptoms, with the severe group experiencing much worse brain fog and activity limitations.

Cognitive Impairment

E2 ModerateCohortPEM not requiredLongitudinal

A Prospective Study of Infectious Mononucleosis in College Students.

Jason, Leonard A, Katz, Ben, Gleason, Kristen et al.·International journal of psychiatry (Overland Park)·2017

This study followed healthy college students over time to see what happens when they catch infectious mononucleosis (IM) and whether some develop ME/CFS afterward. Researchers collected information about students' physical health and emotional well-being before they got sick, while they had IM, and about 6 months later. By tracking students this way, the study aimed to identify which factors might put someone at higher risk of developing ME/CFS after a mono infection.

E2 ModerateCohortPEM requiredObservational

Novel characterisation of mast cell phenotypes from peripheral blood mononuclear cells in chronic fatigue syndrome/myalgic encephalomyelitis patients.

Nguyen, Thao, Johnston, Samantha, Chacko, Anu et al.·Asian Pacific journal of allergy and immunology·2017

This study looked at immune cells called mast cells in the blood of people with ME/CFS and compared them to healthy people. Researchers found that ME/CFS patients—especially those with severe illness—had more mast cells and these cells showed different activation patterns. Mast cells are known to release chemicals that cause inflammation, so understanding them better could help explain some ME/CFS symptoms.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

Differentiating Multiple Sclerosis from Myalgic Encephalomyelitis and Chronic Fatigue Syndrome.

Jason, L A, Ohanian, D, Brown, A et al.·Insights in biomedicine·2017

This study compared how people with MS, ME, and chronic fatigue syndrome experience their illnesses. Researchers surveyed 120 people with MS and 269 people with ME/CFS about their symptoms using a standardized questionnaire. They found that people with ME/CFS reported more severe symptoms and greater functional limitations than people with MS, suggesting these conditions have different disability profiles.

Diagnostics

E2 ModerateBehavioralPEM not requiredCross-Sectional

Fatigue in an adult attention deficit hyperactivity disorder population: A trans-diagnostic approach.

Rogers, Denise C, Dittner, Antonia J, Rimes, Katharine A et al.·The British journal of clinical psychology·2017

This study looked at fatigue in adults with ADHD and compared it to fatigue in people with ME/CFS and healthy people. Researchers found that adults with ADHD experience significantly more fatigue than healthy controls, with about 62% meeting criteria for clinically significant fatigue. Importantly, they discovered that people with ME/CFS and people with ADHD share many similar challenges, including low mood, anxiety, and reduced confidence in their abilities.

Cognitive Impairment

E2 ModerateDiagnosticPEM unclearObservational

Multi-Site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM): Design and Implementation of a Prospective/Retrospective Rolling Cohort Study.

Unger, Elizabeth R, Lin, Jin-Mann S, Tian, Hao et al.·American journal of epidemiology·2017

Researchers created a large study called MCAM to better understand ME/CFS by collecting standardized health information from patients across seven U.S. clinics. They also enrolled healthy people and patients with similar illnesses for comparison. The study tracked patients over time, collected samples for future research, and documented how doctors were treating ME/CFS patients, aiming to identify different types of ME/CFS and find tests that could help diagnosis.

Diagnostics

E2 ModerateBehavioralPEM unclearCross-Sectional

Anxiety and depression in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME): Examining the incidence of health anxiety in CFS/ME.

Daniels, Jo, Brigden, Amberly, Kacorova, Adela·Psychology and psychotherapy·2017

This study looked at how many people with ME/CFS also experience health anxiety—worry about physical symptoms and their meaning. Researchers surveyed 45 ME/CFS patients and found that most had elevated worry about their health, and many had clinically significant health anxiety. The findings suggest that health anxiety is common in ME/CFS and may be worth screening for and treating.

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Prevalence of and risk factors for severe cognitive and sleep symptoms in ME/CFS and MS.

Multimodal and simultaneous assessments of brain and spinal fluid abnormalities in chronic fatigue syndrome and the effects of psychiatric comorbidity.

Clinical Criteria Versus a Possible Research Case Definition in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis.

Comorbidity in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: A Nationwide Population-Based Cohort Study.

From good health to illness with post-infectious fatigue syndrome: a qualitative study of adults' experiences of the illness trajectory.

Establishing Clinically Relevant Severity Levels for the Central Sensitization Inventory.

Do changes in illness perceptions, physical activity, and behavioural regulation influence fatigue severity and health-related outcomes in CFS patients?

Post-Exertional Malaise in Patients with ME and CFS with Comorbid Fibromyalgia.

Sleep Quality in Adolescents With Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME).

Medial prefrontal cortex deficits correlate with unrefreshing sleep in patients with chronic fatigue syndrome.

Long-term follow-up after cognitive behaviour therapy for chronic fatigue syndrome.

Clinically proven mtDNA mutations are not common in those with chronic fatigue syndrome.

The assessment of fatigue: Psychometric qualities and norms for the Checklist individual strength.

An assessment of fatigue in patients with postural orthostatic tachycardia syndrome.

A Prospective Study of Infectious Mononucleosis in College Students.

Novel characterisation of mast cell phenotypes from peripheral blood mononuclear cells in chronic fatigue syndrome/myalgic encephalomyelitis patients.

Differentiating Multiple Sclerosis from Myalgic Encephalomyelitis and Chronic Fatigue Syndrome.

Fatigue in an adult attention deficit hyperactivity disorder population: A trans-diagnostic approach.

Multi-Site Clinical Assessment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MCAM): Design and Implementation of a Prospective/Retrospective Rolling Cohort Study.

Anxiety and depression in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME): Examining the incidence of health anxiety in CFS/ME.

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