ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

2261–2280 of 2,768 studies

E2 ModerateCohortPEM not requiredCross-Sectional

A definition-based analysis of symptoms in a large cohort of patients with chronic fatigue syndrome.

De Becker, P, McGregor, N, De Meirleir, K·Journal of internal medicine·2001

This study looked at 2,073 patients with chronic fatigue to understand how well two common diagnostic criteria (Fukuda and Holmes) identify ME/CFS. The researchers found that the Holmes criteria selected patients with more severe symptoms, while the Fukuda criteria included a broader group with milder cases. Adding or removing certain symptoms from the current diagnostic criteria could help doctors better identify who truly has ME/CFS.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Quantitative assessment of cerebral ventricular volumes in chronic fatigue syndrome.

Lange, G, Holodny, A I, DeLuca, J et al.·Applied neuropsychology·2001

This study looked at brain scans from people with ME/CFS to measure the size of fluid-filled spaces (ventricles) in their brains. Researchers found that people with ME/CFS had slightly larger ventricles compared to healthy controls, suggesting there may be subtle physical changes in the brains of some ME/CFS patients. While this difference was close to being statistically significant, it provides another piece of evidence that ME/CFS involves measurable brain changes.

E2 ModerateCohortPEM not requiredCross-Sectional

Physiological responses to incremental exercise in patients with chronic fatigue syndrome.

Inbar, O, Dlin, R, Rotstein, A et al.·Medicine and science in sports and exercise·2001

Researchers compared how the bodies of 15 people with ME/CFS responded to a gradually increasing exercise test on a treadmill, compared to 15 healthy people. People with ME/CFS showed lower heart rates and weaker cardiovascular responses during exercise, even when they appeared to be pushing themselves as hard as they could. This suggests their bodies may have trouble with either heart function or muscle oxygen use during physical exertion.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Multiple chemical sensitivity and chronic fatigue syndrome in British Gulf War veterans.

Reid, S, Hotopf, M, Hull, L et al.·American journal of epidemiology·2001

This study looked at how often ME/CFS and multiple chemical sensitivity (MCS—a condition where people react badly to everyday chemicals) occurred in British military personnel who served in the Gulf War. Researchers compared three groups: those deployed to the Gulf, those sent to Bosnia, and those who served during the Gulf War period but weren't deployed. They found that both conditions were more common in Gulf veterans, and MCS was strongly linked to pesticide exposure.

Pain and Sensitization

E2 ModerateBehavioralPEM not requiredCross-Sectional

Discriminating between chronic fatigue syndrome and depression: a cognitive analysis.

Moss-Morris, R, Petrie, K J·Psychological medicine·2001

This study compared how people with ME/CFS think and feel about their illness compared to people with depression and healthy people. The researchers found that people with ME/CFS and people with depression have different thought patterns: people with depression tend to blame themselves and doubt their worth, while people with ME/CFS focus on their physical symptoms, see themselves as sick, and tend to rest more to manage their condition. These different thinking patterns stayed consistent over 6 months and were linked to how much disability and fatigue people experienced.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCross-Sectional

Thoroughly modern worries: the relationship of worries about modernity to reported symptoms, health and medical care utilization.

Petrie, K J, Sivertsen, B, Hysing, M et al.·Journal of psychosomatic research·2001

This study looked at whether worries about modern health threats (like pollution, food safety, and radiation) are linked to symptom reporting and chronic fatigue syndrome (CFS). Researchers surveyed over 8,000 people and found that those with higher worries about modernity reported more physical symptoms, food intolerances, and CFS diagnoses. The study suggests that health anxiety about modern threats may influence how people interpret body signals and perceive their health.

E2 ModerateCohortPEM not requiredCase-Control

Cognitive compromise following exercise in monozygotic twins discordant for chronic fatigue syndrome: fact or artifact?

Claypoole, K, Mahurin, R, Fischer, M E et al.·Applied neuropsychology·2001

This study asked whether exercise makes thinking and memory problems worse in people with ME/CFS. Researchers tested 21 pairs of identical twins where one twin had ME/CFS and one did not, asking them to exercise until exhausted and then testing their memory, attention, and thinking speed. The twins with ME/CFS did not show worse cognitive decline after exercise compared to their healthy twin, suggesting that exercise itself does not damage thinking ability.

Post-Exertional Malaise

E2 ModerateBehavioralPEM unclearCross-Sectional

What is chronic fatigue syndrome? Heterogeneity within an international multicentre study.

Wilson, A, Hickie, I, Hadzi-Pavlovic, D et al.·The Australian and New Zealand journal of psychiatry·2001

This study looked at 744 people with chronic fatigue across eight countries to see if they formed different groups based on their symptoms. Researchers found two distinct subgroups: a larger group (68%) with less severe illness and fewer psychiatric issues, and a smaller group (32%) whose symptoms looked more like somatoform illness (where psychological factors strongly influence physical symptoms). Importantly, the proportion of people in each group varied dramatically between countries (6-48%), suggesting that how doctors diagnose and classify ME/CFS is not standardized worldwide.

DiagnosticsCognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Working memory deficits associated with chronic fatigue syndrome.

Dobbs, B M, Dobbs, A R, Kiss, I·Journal of the International Neuropsychological Society : JINS·2001

This study tested memory and thinking skills in 20 people with ME/CFS and compared them to 20 healthy people. The researchers found that people with ME/CFS performed worse on difficult memory tasks, particularly those requiring quick mental switching and staying focused despite distractions. However, their basic memory storage ability was normal.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

A biochemical analysis of people with chronic fatigue who have Irlen Syndrome: speculation concerning immune system dysfunction.

Robinson, G L, McGregor, N R, Roberts, T K et al.·Perceptual and motor skills·2001

This study looked at 61 people with ME/CFS to see if they also had a visual processing problem called Irlen Syndrome (where certain patterns and lighting cause visual discomfort). Researchers found that people with more severe visual problems had different levels of certain fats and amino acids in their blood and urine compared to those with milder visual symptoms. The authors suggest these differences might show signs of immune system activation, possibly from an infection.

Energy MetabolismImmune System

E2 ModerateCohortPEM not requiredCross-Sectional

Divided attention deficits in patients with chronic fatigue syndrome.

Ross, S, Fantie, B, Straus, S F et al.·Applied neuropsychology·2001

This study compared thinking and attention abilities in people with ME/CFS and healthy controls. Researchers found that ME/CFS patients had specific trouble with divided attention—the ability to focus on two things at once (like listening to someone while reading). However, they performed normally on other cognitive tests like memory and word-finding. This suggests that ME/CFS affects one particular type of thinking rather than overall intelligence.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredLongitudinal

Natural course of symptoms in Cambodia veterans: a follow-up study.

De Vries, M, Soetekouw, P M, Van Der Meer, J W et al.·Psychological medicine·2001

Researchers followed Dutch military veterans who served in Cambodia in 1992-1993 and reported fatigue and memory problems after returning home. At 18 months later, about 39% of veterans reported feeling much better or completely recovered, while 57% still had the same symptoms and 4% felt worse. The study found that veterans who started with less severe fatigue and felt they had more control over their symptoms were more likely to improve.

Cognitive Impairment

E2 ModerateCohortPEM not requiredLongitudinal

Longitudinal assessment of neuropsychological functioning, psychiatric status, functional disability and employment status in chronic fatigue syndrome.

Tiersky, L A, DeLuca, J, Hill, N et al.·Applied neuropsychology·2001

Researchers tracked 35 people with ME/CFS over about 3.5 years to see how they changed over time. They found that attention, mood, fatigue, and disability improved somewhat during this period. However, most people remained significantly disabled and unemployed at the end of the study, suggesting that while some aspects may get better, ME/CFS typically leaves people unable to work long-term.

Cognitive Impairment

E2 ModerateCohortPEM not requiredObservational

A twin study of chronic fatigue.

Buchwald, D, Herrell, R, Ashton, S et al.·Psychosomatic medicine·2001

This study looked at whether chronic fatigue runs in families by comparing identical twins to fraternal twins. Researchers found that identical twins were more likely to both have chronic fatigue than fraternal twins, suggesting that genes play a role in who develops the condition. The findings suggest that genetics may account for about half of the reason some people develop chronic fatigue syndrome.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Defensive coping styles in chronic fatigue syndrome.

Creswell, C, Chalder, T·Journal of psychosomatic research·2001

This study looked at how people with ME/CFS cope with stress and worry compared to healthy people and those with other chronic illnesses. Researchers found that people with ME/CFS were more likely to use a coping style where they appear calm and in control on the surface while actually feeling anxious underneath. The study suggests this defensive coping pattern may be connected to how ME/CFS develops and affects the body.

E2 ModerateCohortPEM not requiredCross-Sectional

Neuropsychological function in patients with chronic fatigue syndrome, multiple sclerosis, and depression.

Daly, E, Komaroff, A L, Bloomingdale, K et al.·Applied neuropsychology·2001

This study compared thinking and memory skills in people with ME/CFS, multiple sclerosis, depression, and healthy controls. Researchers found that all three patient groups had trouble with memory, language, and spatial skills. Importantly, even after accounting for depression symptoms, people with ME/CFS still showed memory problems, suggesting their cognitive difficulties are not simply caused by depression.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCross-Sectional

Causal attributions for somatic sensations in patients with chronic fatigue syndrome and their partners.

Butler, J A, Chalder, T, Wessely, S·Psychological medicine·2001

This study looked at how people with ME/CFS explain their symptoms—whether they believe physical causes are responsible versus other factors. Researchers found that patients with ME/CFS tend to blame physical causes for their symptoms more often than healthy controls do. Interestingly, family members living with ME/CFS patients also blamed physical causes for the patients' symptoms, but not for their own symptoms. The researchers suggest that how partners view the illness might affect how well patients recover.

E2 ModerateCohortPEM not requiredCross-Sectional

Patients' perceptions of medical care in chronic fatigue syndrome.

Deale, A, Wessely, S·Social science & medicine (1982)·2001

This study asked 68 ME/CFS patients about their experiences with medical care. Two-thirds of patients were unhappy with the care they received. Patients felt most satisfied when doctors listened, showed genuine interest, and communicated clearly—not necessarily when doctors could cure the illness. Patients were most frustrated when doctors were dismissive, confused about ME/CFS, or gave conflicting advice.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Relationship of brain MRI abnormalities and physical functional status in chronic fatigue syndrome.

Cook, D B, Lange, G, DeLuca, J et al.·The International journal of neuroscience·2001

This study looked at brain MRI scans from 48 ME/CFS patients to see if visible abnormalities in the brain were related to how physically impaired they felt. Researchers found that patients whose brain scans showed abnormalities reported being significantly more physically limited than those with normal-looking scans. This suggests ME/CFS may involve real, measurable changes in the brain rather than being purely psychological.

E2 ModerateCohortPEM not requiredCase-Control

Monozygotic twins discordant for chronic fatigue syndrome: regional cerebral blood flow SPECT.

Lewis, D H, Mayberg, H S, Fischer, M E et al.·Radiology·2001

Researchers used brain imaging scans to look for differences in blood flow to the brain in people with ME/CFS compared to their identical twins who don't have the disease. They found that the brain scans of people with ME/CFS looked very similar to those of their healthy twins, suggesting that ME/CFS may not cause detectable changes in how blood flows through the brain at rest.

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A definition-based analysis of symptoms in a large cohort of patients with chronic fatigue syndrome.

Quantitative assessment of cerebral ventricular volumes in chronic fatigue syndrome.

Physiological responses to incremental exercise in patients with chronic fatigue syndrome.

Multiple chemical sensitivity and chronic fatigue syndrome in British Gulf War veterans.

Discriminating between chronic fatigue syndrome and depression: a cognitive analysis.

Thoroughly modern worries: the relationship of worries about modernity to reported symptoms, health and medical care utilization.

Cognitive compromise following exercise in monozygotic twins discordant for chronic fatigue syndrome: fact or artifact?

What is chronic fatigue syndrome? Heterogeneity within an international multicentre study.

Working memory deficits associated with chronic fatigue syndrome.

A biochemical analysis of people with chronic fatigue who have Irlen Syndrome: speculation concerning immune system dysfunction.

Divided attention deficits in patients with chronic fatigue syndrome.

Natural course of symptoms in Cambodia veterans: a follow-up study.

Longitudinal assessment of neuropsychological functioning, psychiatric status, functional disability and employment status in chronic fatigue syndrome.

A twin study of chronic fatigue.

Defensive coping styles in chronic fatigue syndrome.

Neuropsychological function in patients with chronic fatigue syndrome, multiple sclerosis, and depression.

Causal attributions for somatic sensations in patients with chronic fatigue syndrome and their partners.

Patients' perceptions of medical care in chronic fatigue syndrome.

Relationship of brain MRI abnormalities and physical functional status in chronic fatigue syndrome.

Monozygotic twins discordant for chronic fatigue syndrome: regional cerebral blood flow SPECT.

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