ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

2441–2460 of 2,768 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Impaired associative learning in chronic fatigue syndrome.

Servatius, R J, Tapp, W N, Bergen, M T et al.·Neuroreport·1998

This study tested whether people with ME/CFS have problems with how their brain learns and forms connections between different pieces of information. Researchers measured brain learning using a test where a gentle puff of air is paired with an eye blink stimulus. While ME/CFS patients could hear and feel the stimuli normally, they had difficulty learning to associate the two stimuli together—suggesting their brain's ability to form certain types of connections may be affected.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCase-Control

Post-infection fatigue syndrome following Q fever.

Ayres, J G, Flint, N, Smith, E G et al.·QJM : monthly journal of the Association of Physicians·1998

This study followed 71 people in the UK who were infected with Q fever (a bacterial infection) in 1989 and compared them to 142 similar people who were not infected. Five years later, the infected group reported significantly more fatigue, sweating, breathlessness, and blurred vision than the control group. About 42% of the infected patients met the diagnostic criteria for chronic fatigue syndrome, suggesting that a single Q fever infection can lead to long-lasting tiredness and related symptoms in some people.

E2 ModerateCohortPEM not requiredCross-Sectional

Serum neopterin and somatization in women with chemical intolerance, depressives, and normals.

Bell, I R, Patarca, R, Baldwin, C M et al.·Neuropsychobiology·1998

This study looked at a marker in the blood called neopterin, which may indicate immune system activation, in women with chemical sensitivity (difficulty tolerating everyday chemicals at low levels), women with depression, and healthy women. The researchers found that neopterin levels themselves were similar across groups, but in women with chemical sensitivity, higher neopterin levels were linked with more physical symptoms—a connection not seen in the other groups.

Immune System

E2 ModerateCohortPEM not requiredObservational

Amplified amplitudes of circadian rhythms and nighttime hypotension in patients with chronic fatigue syndrome: improvement by inopamil but not by melatonin.

van de Luit, L, van der Meulen, J, Cleophas, T J et al.·Angiology·1998

This study found that people with ME/CFS have unusually large swings in heart rate and blood pressure throughout the day and night, even though the overall pattern matches healthy controls. Importantly, their nighttime blood pressure drops too low (below 100 mm Hg systolic), which may contribute to fatigue and other symptoms. When treated with a heart-strengthening medication called inopamil, nighttime blood pressure improved, but melatonin actually made it worse.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Effects of exercise on cognitive and motor function in chronic fatigue syndrome and depression.

Blackwood, S K, MacHale, S M, Power, M J et al.·Journal of neurology, neurosurgery, and psychiatry·1998

This study compared how people with ME/CFS, people with depression, and healthy people performed on thinking and strength tests before and after exercise on a treadmill. People with ME/CFS reported feeling much more tired and struggling harder during the exercise than the other groups. After exercising, people with ME/CFS had bigger drops in their ability to focus and pay attention compared to healthy people, suggesting that exercise affects their thinking ability in a specific way.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredLongitudinal

Clinical and serologic follow-up in patients with neuroborreliosis.

Treib, J, Fernandez, A, Haass, A et al.·Neurology·1998

Researchers followed 44 patients who had been treated for a tick-borne brain infection caused by Borrelia bacteria. Even though the patients' neurological symptoms improved after antibiotics, more than half continued to experience ongoing fatigue and other non-specific symptoms similar to chronic fatigue syndrome years later. Some patients also continued to show signs of Borrelia infection in their blood tests.

E2 ModerateCohortPEM not requiredCross-Sectional

Estimating the prevalence of chronic fatigue syndrome among nurses.

Jason, L A, Wagner, L, Rosenthal, S et al.·The American journal of medicine·1998

This study looked at how many nurses have ME/CFS by sending questionnaires to two groups of nurses and then doing more detailed evaluations on those with CFS-like symptoms. The researchers found that nurses may get ME/CFS at higher rates than the general population, possibly because of job-related stress such as shift work, virus exposure, and workplace hazards. This suggests nurses might be at special risk for developing this illness.

E2 ModerateCohortPEM not requiredCross-Sectional

Muscle fibre characteristics and lactate responses to exercise in chronic fatigue syndrome.

Lane, R J, Barrett, M C, Woodrow, D et al.·Journal of neurology, neurosurgery, and psychiatry·1998

Researchers examined muscle samples from 105 ME/CFS patients to understand why they have abnormal responses to exercise, particularly high lactate levels. They found that patients with high lactate responses had fewer type 1 muscle fibres (which are energy-efficient), but this wasn't because they were inactive—it appeared to be a specific muscle problem related to ME/CFS itself.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

The low dose ACTH test in chronic fatigue syndrome and in health.

Scott, L V, Medbak, S, Dinan, T G·Clinical endocrinology·1998

This study tested whether people with ME/CFS have a subtle problem with their stress hormone system, specifically the pituitary gland's ability to signal the adrenal glands to release cortisol. Using a sensitive test with a very small dose of ACTH (a hormone that triggers cortisol release), researchers found that people with ME/CFS showed a weaker cortisol response than healthy people, suggesting their adrenal system may not be functioning optimally.

Endocrine Disruption

E2 ModerateCohortPEM not requiredCross-Sectional

Core body temperature is normal in chronic fatigue syndrome.

Hamilos, D L, Nutter, D, Gershtenson, J et al.·Biological psychiatry·1998

Many people with ME/CFS report feeling like they have a low body temperature or mild fever, but this study found that their actual core body temperature is normal. Researchers continuously measured body temperature every 5 minutes for 24 hours in people with ME/CFS and compared them to healthy people, those with allergies, and those with depression. All groups had similar normal temperatures and similar daily temperature patterns.

E2 ModerateBehavioralPEM not requiredObservational

Predictors of a medical-offset effect among patients receiving antidepressant therapy.

Thompson, D, Hylan, T R, McMullen, W et al.·The American journal of psychiatry·1998

This study looked at insurance records from nearly 1,700 people who started taking antidepressants for depression in the early 1990s. The researchers wanted to understand whether treating depression could also reduce overall healthcare costs. They found that patients with certain conditions—including chronic fatigue syndrome, anxiety, heart disease, and cancer—who stayed on antidepressants for at least 6 months tended to have lower medical bills overall.

E2 ModerateCohortPEM not requiredCase-Control

Naloxone-mediated activation of the hypothalamic-pituitary-adrenal axis in chronic fatigue syndrome.

Scott, L V, Burnett, F, Medbak, S et al.·Psychological medicine·1998

This study looked at whether an opioid-blocking drug called naloxone could trigger the body's stress hormone system in ME/CFS patients versus healthy people. The researchers found that when given naloxone, ME/CFS patients had a blunted response in one stress hormone (ACTH) compared to healthy controls, suggesting that excess opioids are not the primary cause of the stress hormone problems seen in ME/CFS.

Endocrine Disruption

E2 ModerateCohortPEM unclearCross-Sectional

[Incidence and clinical relevance of antibodies to phospholipids, serotonin and ganglioside in patients with sudden deafness and progressive inner ear hearing loss].

Heller, U, Becker, E W, Zenner, H P et al.·HNO·1998

This study looked at whether certain antibodies (proteins the immune system makes) are found more often in people with sudden or progressive hearing loss. Researchers found that about half of hearing loss patients had antibodies against phospholipids and about half to two-thirds had antibodies against serotonin and gangliosides. Interestingly, some patients with hearing loss also had symptoms of ME/CFS and fibromyalgia, suggesting these conditions may be connected through shared immune system abnormalities.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Screening instruments for psychiatric morbidity in chronic fatigue syndrome.

Morriss, R K, Wearden, A J·Journal of the Royal Society of Medicine·1998

This study tested whether two common questionnaires can reliably detect anxiety and depression in ME/CFS patients. Researchers found that the Hospital Anxiety and Depression scale (HAD) works well for this purpose, but the Medical Outcome Survey's mental health scale produced too many false alarms and is not recommended for ME/CFS screening.

E2 ModerateCohortPEM not requiredCross-Sectional

A comparison of salivary cortisol in chronic fatigue syndrome, community depression and healthy controls.

Strickland, P, Morriss, R, Wearden, A et al.·Journal of affective disorders·1998

This study measured cortisol (a stress hormone) in saliva from women with ME/CFS, women with depression, and healthy women to see if cortisol levels differed between groups. Researchers found that women with ME/CFS had lower cortisol levels, especially in the evening and morning, compared to both depressed and healthy women. This suggests that ME/CFS involves different biological changes than depression.

Endocrine Disruption

E2 ModerateCohortPEM not requiredCross-Sectional

Diurnal variation of adrenocortical activity in chronic fatigue syndrome.

MacHale, S M, Cavanagh, J T, Bennie, J et al.·Neuropsychobiology·1998

This study measured stress hormone (cortisol) levels in 30 ME/CFS patients and 15 healthy controls at different times of day. The researchers found that while individual cortisol measurements were similar between groups, ME/CFS patients showed a flattened pattern—their cortisol levels didn't drop as much in the evening as they should. Higher evening cortisol levels were connected to worse overall health and physical functioning in ME/CFS patients.

Endocrine Disruption

E2 ModerateBehavioralPEM not requiredObservational

A naturalistic study of the chronic fatigue syndrome among women in primary care.

Saltzstein, B J, Wyshak, G, Hubbuch, J T et al.·General hospital psychiatry·1998

This study interviewed 15 women with ME/CFS about their experiences and what helped them cope with the illness. Researchers found that 60% of the women reported improvement or recovery. Having strong support from family and friends, a supportive doctor who believed in the diagnosis, and lower depression symptoms were associated with better outcomes.

E2 ModerateCohortPEM not requiredCross-Sectional

[31P-mr spectroscopy of peripheral skeletal musculature under load: demonstration of normal energy metabolites compared with metabolic muscle diseases].

Block, W, Träber, F, Kuhl, C K et al.·RoFo : Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklearmedizin·1998

Researchers used a special MRI scanner to measure how muscles use energy during exercise by looking at chemical changes in the calf. They found that healthy people used two different types of energy pathways during exercise, while people with ME/CFS showed unusual resting energy levels but normal recovery after exercise—unlike patients with genetic metabolic disorders, whose muscles recovered very slowly.

Biomarkers

E2 ModerateBehavioralPEM not requiredCross-Sectional

Early life stress, negative paternal relationships, and chemical intolerance in middle-aged women: support for a neural sensitization model.

Bell, I R, Baldwin, C M, Russek, L G et al.·Journal of women's health·1998

This study looked at whether women with chemical sensitivity (difficulty tolerating everyday chemicals) had experienced more childhood stress or difficult relationships with their fathers compared to women with depression alone or women without these conditions. The researchers found that women with chemical sensitivity had weaker relationships with their fathers and showed signs of nervous system overactivity. The study suggests that repeated exposure to stress early in life might train the nervous system to react more strongly to chemicals and other triggers.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Structure and Determinants of Illness Representations in Chronic Disease: A Comparison of Addison's Disease and Chronic Fatigue Syndrome.

Heijmans, M, De Ridder, D·Journal of health psychology·1998

This study looked at how people with ME/CFS and Addison's disease think about their illnesses—what they believe causes it, how long it will last, whether they can control it, and how it affects their lives. Researchers interviewed 98 ME/CFS patients and 63 Addison's disease patients and found that the two groups had quite different views about their conditions. However, the way these different beliefs connected to each other followed similar patterns in both groups.

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Impaired associative learning in chronic fatigue syndrome.

Post-infection fatigue syndrome following Q fever.

Serum neopterin and somatization in women with chemical intolerance, depressives, and normals.

Amplified amplitudes of circadian rhythms and nighttime hypotension in patients with chronic fatigue syndrome: improvement by inopamil but not by melatonin.

Effects of exercise on cognitive and motor function in chronic fatigue syndrome and depression.

Clinical and serologic follow-up in patients with neuroborreliosis.

Estimating the prevalence of chronic fatigue syndrome among nurses.

Muscle fibre characteristics and lactate responses to exercise in chronic fatigue syndrome.

The low dose ACTH test in chronic fatigue syndrome and in health.

Core body temperature is normal in chronic fatigue syndrome.

Predictors of a medical-offset effect among patients receiving antidepressant therapy.

Naloxone-mediated activation of the hypothalamic-pituitary-adrenal axis in chronic fatigue syndrome.

[Incidence and clinical relevance of antibodies to phospholipids, serotonin and ganglioside in patients with sudden deafness and progressive inner ear hearing loss].

Screening instruments for psychiatric morbidity in chronic fatigue syndrome.

A comparison of salivary cortisol in chronic fatigue syndrome, community depression and healthy controls.

Diurnal variation of adrenocortical activity in chronic fatigue syndrome.

A naturalistic study of the chronic fatigue syndrome among women in primary care.

[31P-mr spectroscopy of peripheral skeletal musculature under load: demonstration of normal energy metabolites compared with metabolic muscle diseases].

Early life stress, negative paternal relationships, and chemical intolerance in middle-aged women: support for a neural sensitization model.

Structure and Determinants of Illness Representations in Chronic Disease: A Comparison of Addison's Disease and Chronic Fatigue Syndrome.

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