ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

2501–2520 of 2,768 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Precipitating factors for the chronic fatigue syndrome.

Salit, I E·Journal of psychiatric research·1997

This study looked at what triggered ME/CFS in 134 patients by asking them about their medical history, infections, and life events. While many patients reported an illness before ME/CFS started, actual proof of a specific infection was rare. Importantly, the researchers found that stressful life events in the year before ME/CFS onset were very common in patients but uncommon in healthy people, suggesting multiple different factors may trigger the illness rather than one single cause.

E2 ModerateCohortPEM unclearObservational

Magnesium deficit in a sample of the Belgian population presenting with chronic fatigue.

Moorkens, G, Manuel y Keenoy, B, Vertommen, J et al.·Magnesium research·1997

This study tested whether people with chronic fatigue have low magnesium levels. Researchers gave 97 patients a special magnesium test and found that 44 had magnesium deficiency. After magnesium supplements, their bodies retained less magnesium, suggesting the treatment may have helped. However, the researchers did not find a clear link between low magnesium and chronic fatigue syndrome itself.

Biomarkers

E2 ModerateCohortPEM not requiredCross-Sectional

The relationship between fibromyalgia and interstitial cystitis.

Clauw, D J, Schmidt, M, Radulovic, D et al.·Journal of psychiatric research·1997

This study compared symptom patterns in people with fibromyalgia, interstitial cystitis (a bladder pain condition), and healthy people. Researchers found that fibromyalgia and IC patients reported very similar types of symptoms beyond their primary complaints, and both groups showed increased pain sensitivity throughout their bodies—not just in the areas they typically experienced pain.

Pain and Sensitization

E2 ModerateBehavioralPEM not requiredCross-Sectional

Outcomes of occupational stressors on nurses: chronic fatigue syndrome--related symptoms.

Wagner, L I, Jason, L A·NursingConnections·1997

This study looked at whether job stress in nurses is connected to ME/CFS-like symptoms. Researchers followed 202 nurses with prolonged exhaustion for one year, asking about their symptoms and work conditions. They found that specific workplace hazards—like fear of accidents and poor working environments—were linked to ME/CFS-related symptoms, though not all stressed nurses developed these symptoms.

E2 ModerateCohortPEM not requiredCase-Control

Immune responses associated with chronic fatigue syndrome: a case-control study.

Mawle, A C, Nisenbaum, R, Dobbins, J G et al.·The Journal of infectious diseases·1997

Researchers compared immune system measurements between ME/CFS patients and healthy controls to see if immune differences could reliably detect the illness. While previous studies reported many immune differences, this careful study found most standard immune tests showed no difference between patients and controls. However, when they looked at specific subgroups—such as patients whose illness started suddenly versus gradually—they did find some immune differences, suggesting that ME/CFS may not be a single uniform immune condition.

Immune System

E2 ModerateCohortPEM not requiredLongitudinal

Epidemic neuromyasthenia and chronic fatigue syndrome in west Otago, New Zealand. A 10-year follow-up.

Levine, P H, Snow, P G, Ranum, B A et al.·Archives of internal medicine·1997

In 1984, an outbreak of prolonged fatigue occurred in West Otago, New Zealand. Researchers followed up with 21 of the original patients about 10 years later and found that nearly half still met the diagnostic criteria for ME/CFS, while the other half had improved or experienced less severe fatigue. Most patients were able to return to their normal activities, though some needed to make lifestyle changes to avoid getting worse again.

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic fatigue syndrome criteria in patients with other forms of unexplained chronic fatigue.

Chester, A C·Journal of psychiatric research·1997

This study looked at nearly 300 young people to see how many had symptoms similar to ME/CFS even though they didn't have a confirmed ME/CFS diagnosis. The researchers found that people with unexplained chronic fatigue shared many symptoms with ME/CFS patients, including fever, sore lymph nodes, muscle weakness, muscle pain, headaches, joint pain, brain fog, and sleep problems. This suggests that ME/CFS symptoms are common in people with other types of long-lasting, unexplained tiredness.

Diagnostics

E2 ModerateCohortPEM not requiredCase-Control

Electron microscopic immunocytological profiles in chronic fatigue syndrome.

Holmes, M J, Diack, D S, Easingwood, R A et al.·Journal of psychiatric research·1997

Researchers used a special microscope to examine immune cells from ME/CFS patients and found structures that resembled a type of virus in 10 out of 17 patients, but not in healthy control subjects. However, when they tried to confirm this finding using additional testing methods, the results were unclear. This suggests something might be different in the cells of some ME/CFS patients, but more research is needed to understand what it means.

Immune System

E2 ModerateCohortPEM unclearCase-Control

Somatomedin C (insulin-like growth factor I) levels in patients with chronic fatigue syndrome.

Bennett, A L, Mayes, D M, Fagioli, L R et al.·Journal of psychiatric research·1997

Researchers measured levels of somatomedin C (a growth-related hormone) in 49 ME/CFS patients and compared them to 30 healthy people. They found that ME/CFS patients had higher levels of this hormone than healthy controls. This is interesting because a similar condition called fibromyalgia shows the opposite pattern—lower levels of this hormone.

Sleep

E2 ModerateCohortPEM not requiredCross-Sectional

High frequency of autoantibodies to insoluble cellular antigens in patients with chronic fatigue syndrome.

von Mikecz, A, Konstantinov, K, Buchwald, D S et al.·Arthritis and rheumatism·1997

Researchers tested blood samples from 60 ME/CFS patients and found that 83% had unusual antibodies (immune proteins) attacking their own cells—specifically targeting proteins that form the structural framework inside and around cell nuclei. These antibodies were rarely seen in healthy people (only 17%), suggesting this autoimmune pattern might be unique to ME/CFS and could potentially help doctors identify the disease.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

An investigation of sympathetic hypersensitivity in chronic fatigue syndrome.

Sendrowski, D P, Buker, E A, Gee, S S·Optometry and vision science : official publication of the American Academy of Optometry·1997

Researchers tested whether ME/CFS patients have unusually sensitive nerves that control pupil size, similar to what is seen in fibromyalgia. They applied eye drops to 29 ME/CFS patients and 33 healthy controls and measured how much the pupils dilated. The results showed no significant difference between the two groups, suggesting that ME/CFS patients do not have this type of nerve sensitivity.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Cognitive functioning is impaired in patients with chronic fatigue syndrome devoid of psychiatric disease.

DeLuca, J, Johnson, S K, Ellis, S P et al.·Journal of neurology, neurosurgery, and psychiatry·1997

This study tested thinking and memory skills in people with ME/CFS and found they performed worse than healthy people, even among those without depression or anxiety. The cognitive problems—like difficulty concentrating, remembering things, and processing information—appear to be a direct part of ME/CFS itself, not caused by mental health conditions. This suggests the 'brain fog' many ME/CFS patients experience is a real biological feature of the illness.

Cognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Chronic fatigue syndrome.

Mawle, A C·Immunological investigations·1997

This study examined whether ME/CFS might be caused by an infection or involve immune system problems. While researchers didn't find a specific virus or bacteria responsible for the illness, they discovered that when they grouped patients based on whether their symptoms started suddenly or gradually, some differences in immune markers appeared between patients and healthy people.

Immune System

E2 ModerateCohortPEM not requiredObservational

Surveillance for chronic fatigue syndrome--four U.S. cities, September 1989 through August 1993.

Reyes, M, Gary, H E, Dobbins, J G et al.·MMWR. CDC surveillance summaries : Morbidity and mortality weekly report. CDC surveillance summaries·1997

Between 1989 and 1993, researchers in four U.S. cities tracked patients with chronic fatigue syndrome (CFS) to understand how common it was and what it looked like. Of 565 patients evaluated, 130 met the CFS criteria. The study found that CFS affected about 4 to 9 people per 100,000 in the general population, but was much more common in white women. Most CFS patients were in their 30s when they got sick and had been ill for about 7 years.

Diagnostics

E2 ModerateBehavioralPEM not requiredCross-Sectional

Physical fatigability and exercise capacity in chronic fatigue syndrome: association with disability, somatization and psychopathology.

Fischler, B, Dendale, P, Michiels, V et al.·Journal of psychosomatic research·1997

This study looked at how people with ME/CFS respond to exercise by measuring whether they can reach their target heart rate during activity. Researchers found that many patients don't reach expected heart rates and that this relates to how disabled they feel in daily life. Interestingly, anxiety and depression didn't explain why people avoided strenuous exercise, suggesting that avoidance behavior in ME/CFS may have different causes than in other conditions.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Does the chronic fatigue syndrome involve the autonomic nervous system?

Freeman, R, Komaroff, A L·The American journal of medicine·1997

This study tested whether ME/CFS patients have problems with their autonomic nervous system—the part of the nervous system that controls automatic functions like heart rate and blood pressure. Researchers found that ME/CFS patients had abnormal heart rate and blood pressure responses during standing and tilting tests, and their nervous system wasn't regulating these responses properly. The findings suggest that either deconditioning from reduced activity, a viral infection damaging the nervous system, or both could explain why many ME/CFS patients feel dizzy or faint when standing up.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

An epidemiologic study of fatigue with relevance for the chronic fatigue syndrome.

Fukuda, K, Dobbins, J G, Wilson, L J et al.·Journal of psychiatric research·1997

Researchers surveyed nearly 1,700 households across four rural Michigan communities to investigate reports of a cluster of chronic fatigue syndrome cases. They found that fatigue was equally common across all communities studied, and the symptoms people with fatigue experienced were similar to generic tiredness rather than distinctly different. The reported cluster of CFS cases could not be confirmed.

E2 ModerateBehavioralPEM unclearCross-Sectional

Sudden vs gradual onset of chronic fatigue syndrome differentiates individuals on cognitive and psychiatric measures.

DeLuca, J, Johnson, S K, Ellis, S P et al.·Journal of psychiatric research·1997

This study looked at whether the way ME/CFS starts—suddenly or gradually—affects thinking abilities and mental health. Researchers tested 36 ME/CFS patients on memory, concentration, and processing speed, and compared them to healthy controls. They found that people whose ME/CFS came on gradually were more likely to have depression or anxiety, while those with sudden onset had more severe memory problems.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCase-Control

Psychological symptoms, somatic symptoms, and psychiatric disorder in chronic fatigue and chronic fatigue syndrome: a prospective study in the primary care setting.

Wessely, S, Chalder, T, Hirsch, S et al.·The American journal of psychiatry·1996

This study followed over 1,900 people in primary care and found that most individuals with ME/CFS also had a current mental health condition like depression or anxiety. The researchers discovered that people with chronic fatigue were much more likely to have psychiatric disorders (60-78%) compared to those without fatigue (19-31%). While the study suggests a strong link between psychiatric conditions and ME/CFS, it does not explain whether one causes the other.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic fatigue complaints in primary care: incidence and diagnostic patterns.

Ward, M H, DeLisle, H, Shores, J H et al.·The Journal of the American Osteopathic Association·1996

This study looked at how doctors in a primary care clinic evaluate patients who complain of chronic fatigue. Researchers reviewed 425 patient charts and found that when patients mentioned chronic fatigue, doctors often did not perform complete evaluations—skipping important tests, mental health screening, and sleep history questions. Most doctors diagnosed patients with depression or general fatigue rather than investigating the chronic fatigue complaint thoroughly.

Diagnostics

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Evidence browser

Precipitating factors for the chronic fatigue syndrome.

Magnesium deficit in a sample of the Belgian population presenting with chronic fatigue.

The relationship between fibromyalgia and interstitial cystitis.

Outcomes of occupational stressors on nurses: chronic fatigue syndrome--related symptoms.

Immune responses associated with chronic fatigue syndrome: a case-control study.

Epidemic neuromyasthenia and chronic fatigue syndrome in west Otago, New Zealand. A 10-year follow-up.

Chronic fatigue syndrome criteria in patients with other forms of unexplained chronic fatigue.

Electron microscopic immunocytological profiles in chronic fatigue syndrome.

Somatomedin C (insulin-like growth factor I) levels in patients with chronic fatigue syndrome.

High frequency of autoantibodies to insoluble cellular antigens in patients with chronic fatigue syndrome.

An investigation of sympathetic hypersensitivity in chronic fatigue syndrome.

Cognitive functioning is impaired in patients with chronic fatigue syndrome devoid of psychiatric disease.

Chronic fatigue syndrome.

Surveillance for chronic fatigue syndrome--four U.S. cities, September 1989 through August 1993.

Physical fatigability and exercise capacity in chronic fatigue syndrome: association with disability, somatization and psychopathology.

Does the chronic fatigue syndrome involve the autonomic nervous system?

An epidemiologic study of fatigue with relevance for the chronic fatigue syndrome.

Sudden vs gradual onset of chronic fatigue syndrome differentiates individuals on cognitive and psychiatric measures.

Psychological symptoms, somatic symptoms, and psychiatric disorder in chronic fatigue and chronic fatigue syndrome: a prospective study in the primary care setting.

Chronic fatigue complaints in primary care: incidence and diagnostic patterns.

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