ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

161–180 of 404 studies

E2 ModerateCohortPEM not requiredCase-Control

Are current chronic fatigue syndrome criteria diagnosing different disease phenotypes?

Maclachlan, Laura, Watson, Stuart, Gallagher, Peter et al.·PloS one·2017

This study looked at whether different diagnostic criteria for ME/CFS are actually identifying the same disease or different versions of it. Researchers tested 49 ME/CFS patients and 10 healthy controls using questionnaires and objective tests of heart function and thinking ability. They found that patients reported more autonomic and cognitive symptoms than controls, but objective heart tests didn't show clear differences—though different patient subgroups did show different levels of impairment on cognitive testing.

Autonomic Nervous SystemDiagnosticsCognitive Impairment

E2 ModerateBehavioralPEM not requiredCross-Sectional

An attention and interpretation bias for illness-specific information in chronic fatigue syndrome.

Hughes, A M, Chalder, T, Hirsch, C R et al.·Psychological medicine·2017

This study looked at whether people with ME/CFS notice illness-related information more than healthy people, and whether they tend to interpret unclear situations in a health-focused way. Researchers found that people with ME/CFS do pay more attention to fatigue-related words and are more likely to interpret ambiguous situations negatively related to their health compared to healthy controls. These thought patterns were connected to beliefs about fear and avoidance, suggesting they may help keep ME/CFS symptoms going.

Cognitive Impairment

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 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 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 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 ModerateCohortPEM not requiredLongitudinal

Workers on transformation of the shelter object of the Chernobyl nuclear power plant into an ecologically-safe system show qEEG abnormalities and cognitive dysfunctions: A follow-up study.

Loganovsky, Konstantyn, Perchuk, Iryna, Marazziti, Donatella·The world journal of biological psychiatry : the official journal of the World Federation of Societies of Biological Psychiatry·2016

This study followed 196 workers who helped clean up and secure the damaged Chernobyl nuclear reactor between 2004 and 2008. Researchers tested their brain electrical activity and thinking skills before and after the work. The workers showed changes in brain wave patterns and developed mild memory and concentration problems after exposure to radiation, similar to symptoms seen in chronic fatigue syndrome.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

The impact of chronic fatigue syndrome on cognitive functioning in adolescents.

Nijhof, Linde N, Nijhof, Sanne L, Bleijenberg, Gijs et al.·European journal of pediatrics·2016

This study looked at how ME/CFS affects thinking and concentration in teenagers. Researchers compared 59 teenagers with ME/CFS to 40 healthy teenagers and found that those with ME/CFS had lower scores on intelligence tests than their school grades would predict. When comparing teenagers' current test scores to their performance before they got sick, the ME/CFS group showed a significant decline, while healthy teens did not.

Cognitive Impairment

E2 ModerateCohortPEM unclearLongitudinal

Neurocognitive complaints and functional status among patients with chronic fatigue syndrome and fibromyalgia.

Schmaling, Karen B, Betterton, Karran L·Quality of life research : an international journal of quality of life aspects of treatment, care and rehabilitation·2016

This study followed 93 patients with ME/CFS over 18 months to understand how cognitive problems (like memory and perception difficulties) and physical function change over time. Patients who had both ME/CFS and fibromyalgia reported more pain, worse physical function, and more cognitive difficulties than those with ME/CFS alone. Interestingly, pain improved over time only for the ME/CFS-only group, suggesting that having both conditions may make recovery slower and more complicated.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

What is in a name? Comparing diagnostic criteria for chronic fatigue syndrome with or without fibromyalgia.

Meeus, Mira, Ickmans, Kelly, Struyf, Filip et al.·Clinical rheumatology·2016

This study compared people with ME/CFS to people with multiple sclerosis and healthy volunteers to see how sick they were and how well they could function. Researchers found that people with ME/CFS had worse physical abilities (like muscle strength and recovery), more severe symptoms, lower quality of life, and more difficulty with daily activities. They also discovered that when ME/CFS patients also had fibromyalgia (widespread pain), their overall symptom burden was much greater.

DiagnosticsCognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Low putamen activity associated with poor reward sensitivity in childhood chronic fatigue syndrome.

Mizuno, Kei, Kawatani, Junko, Tajima, Kanako et al.·NeuroImage. Clinical·2016

This study looked at how the brains of children with ME/CFS respond to rewards compared to healthy children. Using brain imaging, researchers found that a brain region called the putamen (involved in motivation) showed less activity in children with ME/CFS, especially when facing smaller rewards. Lower activity in this area was linked to worse fatigue and less enjoyment from learning.

Cognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Long-term methylphenidate intake in chronic fatigue syndrome.

Blockmans, Daniel, Persoons, Philippe·Acta clinica Belgica·2016

This study looked at whether a medication called methylphenidate (also known as Ritalin) could help ME/CFS patients with concentration problems and fatigue over the long term. Researchers sent surveys to patients who had been prescribed this medication and found that about one-third of those still taking it reported significant improvement in both fatigue and concentration difficulties, and were able to work more hours.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Abnormal resting state functional connectivity in patients with chronic fatigue syndrome: an arterial spin-labeling fMRI study.

Boissoneault, Jeff, Letzen, Janelle, Lai, Song et al.·Magnetic resonance imaging·2016

This study used a special brain imaging technique to look at how different parts of the brain communicate with each other in ME/CFS patients compared to healthy people. Researchers found that people with ME/CFS have unusual patterns of brain communication, particularly in areas related to memory, thinking, and movement. Importantly, the strength of connections in memory-related brain regions was linked to how severe patients' fatigue symptoms were.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

A Cross Cultural Comparison of Disability and Symptomatology Associated with CFS.

Zdunek, Maria, Jason, Leonard A, Evans, Meredyth et al.·International journal of psychology and behavioral sciences·2015

This study compared ME/CFS symptoms and disability between patients in the United States and the United Kingdom to see if the illness looks different depending on where people live. Researchers found that UK patients reported more mental health problems, pain, memory/concentration issues, and immune symptoms, while US patients more often experienced sudden illness onset and attributed their illness to physical causes. The study suggests that ME/CFS may present somewhat differently across these two countries.

Pain and SensitizationSleepCognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

The association between daytime napping and cognitive functioning in chronic fatigue syndrome.

Gotts, Zoe M, Ellis, Jason G, Deary, Vincent et al.·PloS one·2015

This study looked at how sleep patterns, especially daytime napping, affect fatigue, sleepiness, and thinking ability in people with ME/CFS. Researchers asked 118 patients to keep a sleep diary for two weeks and complete daily assessments of their symptoms. They found that afternoon napping was linked to worse cognitive problems and increased daytime sleepiness, suggesting that when and how much patients nap may influence how well they can think and function.

SleepCognitive Impairment

E2 ModerateCohortPEM unclearCross-Sectional

The effect of fatigue and fibromyalgia on sexual dysfunction in women with chronic fatigue syndrome.

Blazquez, Alicia, Ruiz, Eva, Aliste, Luisa et al.·Journal of sex & marital therapy·2015

This study examined sexual problems in 615 women with ME/CFS and found that sexual dysfunction was more common in those with worse fatigue, more cognitive and nervous system symptoms, and co-occurring conditions like fibromyalgia or Sjögren's syndrome. The researchers used a validated questionnaire to measure sexual satisfaction and identified patterns linking symptom severity to sexual health problems. This suggests that ME/CFS symptoms directly impact intimate relationships and sexual function.

Cognitive Impairment

E2 ModerateCohortPEM requiredCross-Sectional

Study findings challenge the content validity of the Canadian Consensus Criteria for adolescent chronic fatigue syndrome.

Asprusten, Tarjei Tørre, Fagermoen, Even, Sulheim, Dag et al.·Acta paediatrica (Oslo, Norway : 1992)·2015

Researchers tested whether the Canadian Consensus Criteria—a set of guidelines used to diagnose ME/CFS in teenagers—actually identify meaningful differences between patients. They compared 120 adolescents with ME/CFS, grouping them by whether they met these criteria or not. The study found that the two groups were nearly identical in most disease markers and how they recovered over time, suggesting the criteria may not be capturing important real-world differences between patients.

Cognitive Impairment

E2 ModerateCohortPEM unclearObservational

Computerized training improves verbal working memory in patients with myalgic encephalomyelitis/chronic fatigue syndrome: A pilot study.

Maroti, Daniel, Westerberg, Annika Fryxell, Saury, Jean-Michel et al.·Journal of rehabilitation medicine·2015

Many people with ME/CFS struggle with memory and thinking problems. This small study tested whether spending 30-45 minutes a day for 5 weeks doing computerized memory exercises on a computer could help. Nine out of eleven patients who completed the training showed real improvements in working memory and attention, while a control group of patients who didn't do the training showed no improvement.

Cognitive Impairment

E2 ModerateCohortPEM unclearCross-Sectional

Associations Between Cognitive Performance and Pain in Chronic Fatigue Syndrome: Comorbidity with Fibromyalgia Does Matter.

Ickmans, Kelly, Meeus, Mira, De Kooning, Margot et al.·Pain physician·2015

This study looked at whether pain and thinking problems are connected in people with ME/CFS, and whether having fibromyalgia alongside ME/CFS changes this relationship. Researchers tested 48 patients with ME/CFS (some with fibromyalgia, some without) and 30 healthy people on memory and attention tasks, then measured their pain responses. They found that the type of pain problem matters: in patients with both conditions, a specific pain-processing difference predicted thinking problems, while in ME/CFS-only patients, reported pain levels predicted thinking problems.

Pain and SensitizationCognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Attention network test: assessment of cognitive function in chronic fatigue syndrome.

Togo, Fumiharu, Lange, Gudrun, Natelson, Benjamin H et al.·Journal of neuropsychology·2015

This study tested whether a computer-based attention test called the Attention Network Task (ANT) could measure thinking and processing speed problems in ME/CFS patients. Researchers compared 41 ME/CFS patients (some with depression, some without) to 29 healthy controls and found that ME/CFS patients took longer to respond to tasks, especially when the tasks were complex, even though they made the same number of mistakes as controls. This suggests that slowed thinking speed, rather than errors, may be the main cognitive problem in ME/CFS.

Cognitive Impairment

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Are current chronic fatigue syndrome criteria diagnosing different disease phenotypes?

An attention and interpretation bias for illness-specific information in chronic fatigue syndrome.

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

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

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

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

Workers on transformation of the shelter object of the Chernobyl nuclear power plant into an ecologically-safe system show qEEG abnormalities and cognitive dysfunctions: A follow-up study.

The impact of chronic fatigue syndrome on cognitive functioning in adolescents.

Neurocognitive complaints and functional status among patients with chronic fatigue syndrome and fibromyalgia.

What is in a name? Comparing diagnostic criteria for chronic fatigue syndrome with or without fibromyalgia.

Low putamen activity associated with poor reward sensitivity in childhood chronic fatigue syndrome.

Long-term methylphenidate intake in chronic fatigue syndrome.

Abnormal resting state functional connectivity in patients with chronic fatigue syndrome: an arterial spin-labeling fMRI study.

A Cross Cultural Comparison of Disability and Symptomatology Associated with CFS.

The association between daytime napping and cognitive functioning in chronic fatigue syndrome.

The effect of fatigue and fibromyalgia on sexual dysfunction in women with chronic fatigue syndrome.

Study findings challenge the content validity of the Canadian Consensus Criteria for adolescent chronic fatigue syndrome.

Computerized training improves verbal working memory in patients with myalgic encephalomyelitis/chronic fatigue syndrome: A pilot study.

Associations Between Cognitive Performance and Pain in Chronic Fatigue Syndrome: Comorbidity with Fibromyalgia Does Matter.

Attention network test: assessment of cognitive function in chronic fatigue syndrome.

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