ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

3281–3300 of 6,161 studies

E2 ModerateBehavioralPEM not requiredCross-Sectional

A neuropsychological study of the postpolio syndrome: support for depression without neuropsychological impairment.

Hazendonk, K M, Crowe, S F·Neuropsychiatry, neuropsychology, and behavioral neurology·2000

This study compared how well people with postpolio syndrome could think and remember compared to polio survivors without the condition and healthy controls. Although people with postpolio syndrome reported mental fatigue and memory problems, standard tests of thinking and memory showed no real differences between the groups. The researchers found that depression and worry about illness were more common in the postpolio syndrome group and may explain why patients feel cognitively impaired.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCase-Control

Human herpesviruses 6 and 7 in chronic fatigue syndrome: a case-control study.

Reeves, W C, Stamey, F R, Black, J B et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·2000

Researchers tested whether three common viruses (HHV-6A, HHV-6B, and HHV-7) might be linked to ME/CFS. They compared blood samples from 26 ME/CFS patients with 52 healthy people and looked for signs of active or dormant virus infection. The study found no meaningful differences between the two groups, suggesting these particular viruses are not associated with ME/CFS.

E2 ModerateCohortPEM not requiredCross-Sectional

The difference in patterns of motor and cognitive function in chronic fatigue syndrome and severe depressive illness.

Lawrie, S M, MacHale, S M, Cavanagh, J T et al.·Psychological medicine·2000

This study compared thinking and physical abilities in people with ME/CFS, people with depression, and healthy individuals. Researchers found that people with ME/CFS had worse memory and thinking skills than healthy people, but generally better than those with depression. Both ME/CFS and depression groups showed significant problems with muscle strength and motor control compared to healthy controls.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCase-Control

Personality in adolescents with chronic fatigue syndrome.

Rangel, L, Garralda, E, Levin, M et al.·European child & adolescent psychiatry·2000

This study looked at personality traits in teenagers with ME/CFS and compared them to healthy teenagers. Researchers found that adolescents with ME/CFS were more likely to show certain personality features like being very conscientious, feeling vulnerable, experiencing worthlessness, and having unstable emotions. While personality difficulties were linked to worse social skills and more psychological symptoms, the study suggests these traits are separate from having psychiatric disorders.

E2 ModerateCohortPEM not requiredCross-Sectional

High nocturnal melatonin in adolescents with chronic fatigue syndrome.

Knook, L, Kavelaars, A, Sinnema, G et al.·The Journal of clinical endocrinology and metabolism·2000

Researchers measured melatonin (a natural hormone that helps control sleep) in saliva samples from 13 teenagers with ME/CFS and 15 healthy teenagers. They found that ME/CFS patients had significantly higher melatonin levels during the night, yet paradoxically, all the ME/CFS patients reported their sleep felt unrefreshing and unrestorative. Based on this finding, the researchers suggested that giving melatonin supplements to teenagers with ME/CFS may not be helpful.

Sleep

E2 ModerateCohortPEM not requiredCross-Sectional

Cerebral perfusion in chronic fatigue syndrome and depression.

MacHale, S M, Lawŕie, S M, Cavanagh, J T et al.·The British journal of psychiatry : the journal of mental science·2000

Researchers used brain imaging to measure blood flow in different areas of the brain in people with ME/CFS, people with depression, and healthy volunteers. They found that people with ME/CFS had increased blood flow in certain deep brain structures (the thalamus and related areas), which was similar to what they saw in depressed patients. However, people with ME/CFS had a different pattern than depressed patients in other brain regions, suggesting these are related but distinct conditions.

E2 ModerateCohortPEM unclearCross-Sectional

Abnormal neuropsychological findings are not necessarily a sign of cerebral impairment: a matched comparison between chronic fatigue syndrome and multiple sclerosis.

van der Werf, S P, Prins, J B, Jongen, P J et al.·Neuropsychiatry, neuropsychology, and behavioral neurology·2000

This study compared how people with ME/CFS and people with multiple sclerosis (MS) performed on memory and thinking tests. The researchers found that people with ME/CFS were more likely to show signs of reduced effort on memory tests, but both groups had similar rates of poor performance on standard cognitive tests. This suggests that poor test results in ME/CFS patients might sometimes reflect how hard they're trying during the test, rather than actual brain damage.

Cognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Identifying physical activity patterns in chronic fatigue syndrome using actigraphic assessment.

van der Werf, S P, Prins, J B, Vercoulen, J H et al.·Journal of psychosomatic research·2000

Researchers used a motion-tracking device to measure physical activity patterns in 277 ME/CFS patients over 12 days and compared them to 47 healthy people. Patients with ME/CFS showed less intense bursts of activity, shorter activity periods, and longer rest times afterward. About one-fourth of patients were identified as 'pervasively passive'—meaning they had very low activity levels throughout the entire study period.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCase-Control

A 37 kDa 2-5A binding protein as a potential biochemical marker for chronic fatigue syndrome.

De Meirleir, K, Bisbal, C, Campine, I et al.·The American journal of medicine·2000

Researchers found a specific protein (37 kDa) in the blood cells of 88% of ME/CFS patients, compared to only 28% of control subjects. This protein was present in much higher amounts in ME/CFS patients, suggesting it could potentially be used as a blood test to help identify the condition.

BiomarkersImmune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome: a woman's dilemma.

Tuck, I, Wallace, D·Health care for women international·2000

This study looked at how ME/CFS affects women's lives by interviewing 22 women and surveying 42 others about their experiences. The researchers found that the illness significantly disrupts women's work, relationships, and how they see themselves. The study highlights that living with ME/CFS and managing its symptoms has a major impact on quality of life beyond just the medical aspects of the disease.

E2 ModerateCohortPEM not requiredCross-Sectional

The capnography head-up tilt test for evaluation of chronic fatigue syndrome.

Naschitz, J E, Rosner, I, Rozenbaum, M et al.·Seminars in arthritis and rheumatism·2000

This study tested whether a special tilt table test that measures blood pressure, heart rate, breathing, and carbon dioxide levels could help diagnose ME/CFS. Researchers compared 32 ME/CFS patients to 32 healthy people during this test. ME/CFS patients showed abnormal responses—like drops in blood pressure, increases in heart rate, faster breathing, and lower carbon dioxide levels—while healthy people did not, suggesting this test might help identify ME/CFS.

Autonomic Nervous System

E2 ModerateDiagnosticPEM not requiredCross-Sectional

Fatigue rating scales: an empirical comparison.

Taylor, R R, Jason, L A, Torres, A·Psychological medicine·2000

This study compared two popular questionnaires that doctors use to measure fatigue in ME/CFS patients: the Fatigue Scale and the Fatigue Severity Scale. Researchers tested both tools on people with varying levels of fatigue, including those with ME/CFS-like symptoms and healthy people. The study found that while both tools are useful, the Fatigue Severity Scale better captures how fatigue affects daily functioning and quality of life in people with ME/CFS.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Attributions in chronic fatigue syndrome and fibromyalgia syndrome in tertiary care.

Neerinckx, E, Van Houdenhove, B, Lysens, R et al.·The Journal of rheumatology·2000

This study looked at what 192 patients with ME/CFS, fibromyalgia, or chronic pain believed was causing their illness. Most patients thought their condition had both physical causes (like a virus or chemical imbalance) and emotional causes (like stress). The researchers found that patients' beliefs about what caused their illness were quite varied, and these beliefs did not differ much based on their specific diagnosis.

E2 ModerateCohortPEM unclearObservational

[Relationship between fatigue in multiple sclerosis and the chronic fatigue syndrome].

Grimaud, J·Revue neurologique·2000

This study examined whether the severe tiredness experienced by people with multiple sclerosis (MS) is similar to the fatigue seen in ME/CFS. The research looked at how fatigue presents differently in these two conditions and whether they share common features. Understanding these similarities and differences can help doctors better recognize and treat fatigue in both diseases.

E2 ModerateCohortPEM not requiredCase-Control

Blood parameters indicative of oxidative stress are associated with symptom expression in chronic fatigue syndrome.

Richards, R S, Roberts, T K, McGregor, N R et al.·Redox report : communications in free radical research·2000

Researchers compared blood samples from 33 people with ME/CFS and 27 healthy people, looking for signs of oxidative stress—a type of cellular damage caused by unstable molecules called free radicals. They found that people with ME/CFS had higher levels of certain markers of this damage, particularly a substance called methaemoglobin. The levels of these damage markers were strongly linked to how severe patients' symptoms were, including fatigue, pain, sleep problems, and cognitive difficulties.

Biomarkers

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome: an examination of the phases.

Jason, L A, Fricano, G, Taylor, R R et al.·Journal of clinical psychology·2000

This study tested a tool called the Fennell Phase Inventory, which measures four distinct phases that people with ME/CFS typically go through: Crisis, Stabilization, Resolution, and Integration. Researchers gave 65 patients diagnosed by doctors the inventory along with other questionnaires about their symptoms, daily functioning, and coping strategies. The results supported the theory that ME/CFS patients progress through these predictable phases, with each phase showing different levels of disability and different ways of coping.

E2 ModerateCohortPEM unclearCross-Sectional

Neurally mediated hypotension in fatigued Gulf War veterans: a preliminary report.

Davis, S D, Kator, S F, Wonnett, J A et al.·The American journal of the medical sciences·2000

This study tested whether fatigued Gulf War veterans have problems with blood pressure control when standing up quickly (a condition called neurally mediated hypotension), similar to what researchers have seen in ME/CFS patients. The researchers tilted 14 fatigued Gulf War veterans on a special table and compared their responses to two groups of unfatigued veterans and non-veterans. They found that fatigued veterans were more likely to experience dangerous drops in blood pressure during the test, suggesting their autonomic nervous system (the part that automatically controls heart rate and blood pressure) may not be working properly.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Exercise capacity in chronic fatigue syndrome.

De Becker, P, Roeykens, J, Reynders, M et al.·Archives of internal medicine·2000

This study measured how much exercise women with ME/CFS could tolerate compared to healthy women without the condition. Patients with ME/CFS were able to exercise at only about half the capacity of healthy controls—they couldn't reach high heart rates and couldn't sustain heavy workloads. The findings show that ME/CFS significantly limits physical ability in ways that can be objectively measured.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCase-Control

Proton magnetic resonance spectroscopy and morphometry of the hippocampus in chronic fatigue syndrome.

Brooks, J C, Roberts, N, Whitehouse, G et al.·The British journal of radiology·2000

This study used brain imaging to examine a part of the brain called the hippocampus in people with ME/CFS and healthy controls. While the size of the hippocampus was normal in ME/CFS patients, a specific chemical marker called N-acetylaspartate was significantly lower in the right side of the hippocampus compared to healthy people. This suggests there may be subtle differences in how brain cells are functioning in ME/CFS, even when the brain structure looks normal.

E2 ModerateCohortPEM not requiredLongitudinal

The course of severe chronic fatigue syndrome in childhood.

Rangel, L, Garralda, M E, Levin, M et al.·Journal of the Royal Society of Medicine·2000

This study followed 25 children with severe chronic fatigue syndrome for about 3.5 years after their illness began. Most children (two-thirds) eventually recovered and returned to normal activities, though the illness caused serious problems during its worst phases, including extended time out of school. The researchers found that children who had a clear physical trigger for their illness, started feeling sick in the autumn, or came from higher-income families were more likely to recover.

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A neuropsychological study of the postpolio syndrome: support for depression without neuropsychological impairment.

Human herpesviruses 6 and 7 in chronic fatigue syndrome: a case-control study.

The difference in patterns of motor and cognitive function in chronic fatigue syndrome and severe depressive illness.

Personality in adolescents with chronic fatigue syndrome.

High nocturnal melatonin in adolescents with chronic fatigue syndrome.

Cerebral perfusion in chronic fatigue syndrome and depression.

Abnormal neuropsychological findings are not necessarily a sign of cerebral impairment: a matched comparison between chronic fatigue syndrome and multiple sclerosis.

Identifying physical activity patterns in chronic fatigue syndrome using actigraphic assessment.

A 37 kDa 2-5A binding protein as a potential biochemical marker for chronic fatigue syndrome.

Chronic fatigue syndrome: a woman's dilemma.

The capnography head-up tilt test for evaluation of chronic fatigue syndrome.

Fatigue rating scales: an empirical comparison.

Attributions in chronic fatigue syndrome and fibromyalgia syndrome in tertiary care.

[Relationship between fatigue in multiple sclerosis and the chronic fatigue syndrome].

Blood parameters indicative of oxidative stress are associated with symptom expression in chronic fatigue syndrome.

Chronic fatigue syndrome: an examination of the phases.

Neurally mediated hypotension in fatigued Gulf War veterans: a preliminary report.

Exercise capacity in chronic fatigue syndrome.

Proton magnetic resonance spectroscopy and morphometry of the hippocampus in chronic fatigue syndrome.

The course of severe chronic fatigue syndrome in childhood.

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