ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2785 studies

2061–2080 of 2,785 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Regional distribution of fatiguing illnesses in the United States: a pilot study.

Bierl, Cynthia, Nisenbaum, Rosane, Hoaglin, David C et al.·Population health metrics·2004

Researchers called people across the United States and asked about chronic fatigue lasting at least 6 months. They estimated that about 2.2 million American adults have a condition that looks like ME/CFS based on symptoms alone, without medical testing. The study found that fatiguing illnesses were slightly more common in rural areas than cities, but there were no major differences between different regions of the country.

E2 ModerateCohortPEM not requiredLongitudinal

Prevalence of chronic fatigue syndrome-like caseness in the working population: results from the Maastricht cohort study.

Huibers, M J H, Kant, I J, Swaen, G M H et al.·Occupational and environmental medicine·2004

This study looked at how common ME/CFS-like illness is among working people in the Netherlands. Researchers followed nearly 5,500 employees over about 3 years and 8 months and found that 3.6% met the medical criteria for ME/CFS, even though only 0.36% had actually been diagnosed by a doctor. This suggests that ME/CFS may be going unrecognized and undiagnosed in many working people.

E2 ModerateCohortPEM not requiredCase-Control

Cognitive processing in monozygotic twins discordant for chronic fatigue syndrome.

Mahurin, Roderick K, Claypoole, Keith H, Goldberg, Jack H et al.·Neuropsychology·2004

This study tested thinking and processing speed in identical twins where one had ME/CFS and one didn't, compared to healthy people without the condition. Researchers found that both twin groups—even the healthy ones—were slower at tasks requiring quick thinking compared to unrelated healthy controls, but both groups performed equally well on untimed thinking tasks. This suggests that slower processing speed may run in families rather than being caused by ME/CFS itself.

Cognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Chronic fatigue syndrome and other fatiguing illnesses in adolescents: a population-based study.

Jones, James F, Nisenbaum, Rosane, Solomon, Laura et al.·The Journal of adolescent health : official publication of the Society for Adolescent Medicine·2004

Researchers surveyed families in Kansas to see how many adolescents (ages 12-17) had chronic fatigue syndrome (CFS) or other long-term fatigue illnesses. They found that CFS is much less common in teenagers than in adults. When both teens and their parents were carefully evaluated by doctors, none of the participating teenagers actually met the full definition of CFS, though some had prolonged fatigue from other causes.

Diagnostics

E2 ModerateCohortPEM not requiredObservational

Prediction of peak oxygen uptake in patients fulfilling the 1994 CDC criteria for chronic fatigue syndrome.

Nijs, Jo, De Meirleir, Kenny·Clinical rehabilitation·2004

This study looked for a simple way to predict how much oxygen someone with ME/CFS can use during exercise (called VO2peak), which is a measure of exercise capacity. Researchers tested 240 ME/CFS patients on exercise bikes and found that by measuring the maximum workload a patient could achieve, they could estimate their oxygen use fairly accurately with a simple calculation.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue and indicators of long-term employment disability in psychosomatic inpatients.

Tritt, Karin, Nickel, Marius, Mitterlehner, Ferdinand et al.·Wiener klinische Wochenschrift·2004

This study looked at 1,000 patients at a hospital clinic to understand why some people with severe, persistent exhaustion become unable to work. The researchers found that patients who couldn't work had stronger focus on physical symptoms, difficulty recognizing their own feelings, and trouble getting along with coworkers—not necessarily because they were sicker, but because of how they coped with their condition.

E2 ModerateCohortPEM not requiredObservational

Health effects of dental amalgam exposure: a retrospective cohort study.

Bates, Michael N, Fawcett, Jackie, Garrett, Nick et al.·International journal of epidemiology·2004

This study looked at whether mercury in dental fillings causes health problems like chronic fatigue syndrome, multiple sclerosis, or Alzheimer's disease. Researchers tracked 20,000 New Zealand Defence Force members for about 20 years and compared how many dental fillings they received to whether they developed these illnesses. The study found no link between dental fillings and chronic fatigue syndrome, suggesting that amalgam fillings are unlikely to cause ME/CFS.

E2 ModerateCohortPEM unclearLongitudinal

Childhood predictors of self reported chronic fatigue syndrome/myalgic encephalomyelitis in adults: national birth cohort study.

Viner, Russell, Hotopf, Matthew·BMJ (Clinical research ed.)·2004

This study followed over 11,000 children born in 1970 into adulthood to understand what childhood factors might lead to developing ME/CFS later in life. Researchers found that people who were less active as children, had long-term health conditions in childhood, or were female had higher chances of developing ME/CFS by age 30. Importantly, childhood stress or psychological problems were not found to be risk factors, contrary to some earlier beliefs.

E2 ModerateBehavioralPEM not requiredObservational

Kinesiophobia in chronic fatigue syndrome: assessment and associations with disability.

Nijs, Jo, De Meirleir, Kenny, Duquet, William·Archives of physical medicine and rehabilitation·2004

This study looked at whether ME/CFS patients who fear movement (kinesiophobia) have more activity limitations than others. Researchers used a questionnaire to measure fear of movement and found that patients with higher fear of movement reported more difficulty with daily activities, but this fear did not actually relate to how much exercise capacity they had when tested on a bike.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredObservational

The economic impact of chronic fatigue syndrome.

Reynolds, Kenneth J, Vernon, Suzanne D, Bouchery, Ellen et al.·Cost effectiveness and resource allocation : C/E·2004

This study looked at how much money people with ME/CFS lose because they cannot work or be as productive at home. Researchers found that people with ME/CFS lose about $20,000 per year in productivity on average, and the total cost to the United States economy is around $9.1 billion annually. This financial burden is similar to what other serious diseases like digestive disorders or nervous system conditions cost the country.

E2 ModerateReviewPEM unclearReview-Narrative

Chronic fatigue syndrome: matching exercise to symptom fluctuations.

Skinner, James S·The Physician and sportsmedicine·2004

People with ME/CFS often feel extremely tired and experience worsening fatigue after physical activity, leading many to stop exercising altogether and become weaker. This review suggests that gentle, intermittent exercise at low to moderate intensity may actually help improve how much activity patients can do and reduce their fatigue and other symptoms. The good news is that standard exercise testing doesn't make ME/CFS symptoms worse, and matching exercise type to daily symptom changes appears to be a practical approach.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredLongitudinal

Chronic fatigue syndrome in adolescents: a follow-up study.

Gill, Anna C, Dosen, Ana, Ziegler, John B·Archives of pediatrics & adolescent medicine·2004

This study followed teenagers with severe fatigue for up to 8 years to see how many got better. Teenagers who had been fatigued for less than 6 months all recovered completely. Those diagnosed with ME/CFS had worse outcomes, with less than a quarter showing near-complete improvement, though some did get partially better. Being admitted to the hospital did not change whether teenagers recovered or not.

E2 ModerateMechanismPEM not requiredMechanistic

Reduction of serotonin transporters of patients with chronic fatigue syndrome.

Yamamoto, Shigeyuki, Ouchi, Yasuomi, Onoe, Hirotaka et al.·Neuroreport·2004

Researchers used brain imaging (PET scans) to study a chemical messenger in the brain called serotonin in ME/CFS patients compared to healthy people. They found that ME/CFS patients had lower levels of serotonin transporters—the proteins that carry serotonin—in a specific brain region called the rostral anterior cingulate. This suggests that serotonin system dysfunction may be involved in ME/CFS symptoms.

E2 ModerateCohortPEM not requiredCross-Sectional

IgM serum antibodies to Epstein-Barr virus are uniquely present in a subset of patients with the chronic fatigue syndrome.

Lerner, A Martin, Beqaj, Safedin H, Deeter, Robert G et al.·In vivo (Athens, Greece)·2004

Researchers tested blood samples from 58 ME/CFS patients and 68 healthy controls for antibodies to Epstein-Barr virus (EBV), a common virus that causes mononucleosis. They found that about half of the ME/CFS patients (33 out of 58) had elevated levels of a specific type of antibody called IgM against EBV, while none of the healthy controls had this pattern. These antibody levels stayed elevated in ME/CFS patients for up to 3.5 years, suggesting this test might help identify a particular subgroup of ME/CFS patients.

Immune System

E2 ModerateBehavioralPEM not requiredObservational

Posttraumatic stress disorder and physical illness: results from clinical and epidemiologic studies.

Boscarino, Joseph A·Annals of the New York Academy of Sciences·2004

This study looked at whether people with PTSD (post-traumatic stress disorder) are more likely to develop physical illnesses, including chronic fatigue syndrome. Researchers examined nearly 2,500 Vietnam veterans and found that those with chronic PTSD had higher rates of autoimmune diseases and showed immune system changes that could explain why trauma survivors develop long-lasting health problems.

Immune System

E2 ModerateCohortPEM not requiredCase-Control

Association between chronic fatigue syndrome and the corticosteroid-binding globulin gene ALA SER224 polymorphism.

Torpy, David J, Bachmann, A W, Gartside, M et al.·Endocrine research·2004

This study investigated whether a specific genetic variation in a gene called CBG (corticosteroid-binding globulin) might increase the risk of developing ME/CFS. The researchers compared 248 ME/CFS patients with 248 healthy controls and found a trend suggesting that people with two copies of a particular genetic variant (called serine224) were more common among ME/CFS patients. This variant was associated with higher CBG levels in the blood but lower cortisol levels, which could affect how the body manages stress and inflammation.

Endocrine Disruption

E2 ModerateCohortPEM not requiredCross-Sectional

Prevalence of chronic disabling fatigue in children and adolescents.

Farmer, Anne, Fowler, Tom, Scourfield, Jane et al.·The British journal of psychiatry : the journal of mental science·2004

This study looked at how common disabling fatigue is in children and teenagers aged 8-17 years old. Researchers asked parents whether their children had ever experienced periods of extreme tiredness lasting more than a few days, and then followed up with phone interviews. They found that about 2-3% of young people experienced disabling fatigue lasting at least 3 months, while about 1% met criteria similar to adult ME/CFS.

E2 ModerateBehavioralPEM not requiredLongitudinal

Predictors of outcome in fatigued employees on sick leave: results from a randomised trial.

Huibers, Marcus J H, Bleijenberg, Gijs, van Amelsvoort, Ludovic G P M et al.·Journal of psychosomatic research·2004

This study followed 151 tired employees on sick leave for one year to see who recovered and who returned to work. The researchers found that about 43% of people stopped having persistent fatigue, and 62% went back to work. Interestingly, getting better from fatigue and returning to work were driven by different factors—people who recovered from fatigue tended to view their condition differently psychologically, while those who returned to work tended to be younger, male, and have fewer thinking/memory problems.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCase-Control

Physiological responses during a submaximal cycle test in chronic fatigue syndrome.

Wallman, Karen E, Morton, Alan R, Goodman, Carmel et al.·Medicine and science in sports and exercise·2004

This study compared how people with ME/CFS and healthy people without the condition respond to exercise on a stationary bike. The main finding was that people with ME/CFS felt much more exhausted during the same amount of exercise, and they couldn't exercise as hard before becoming tired. Both groups were matched carefully so they had similar activity levels before the study, which makes the comparison more fair.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredObservational

Disability evaluation in chronic fatigue syndrome: associations between exercise capacity and activity limitations/participation restrictions.

Nijs, J, De Meirleir, K, Wolfs, S et al.·Clinical rehabilitation·2004

This study looked at whether ME/CFS patients with lower exercise capacity also have more difficulty with daily activities. Researchers tested 77 patients on an exercise bike and asked them to report how limited they were in everyday life. They found a modest connection between poor exercise performance and activity limitations, but the link was not strong enough to predict disability from exercise tests alone.

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Regional distribution of fatiguing illnesses in the United States: a pilot study.

Prevalence of chronic fatigue syndrome-like caseness in the working population: results from the Maastricht cohort study.

Cognitive processing in monozygotic twins discordant for chronic fatigue syndrome.

Chronic fatigue syndrome and other fatiguing illnesses in adolescents: a population-based study.

Prediction of peak oxygen uptake in patients fulfilling the 1994 CDC criteria for chronic fatigue syndrome.

Chronic fatigue and indicators of long-term employment disability in psychosomatic inpatients.

Health effects of dental amalgam exposure: a retrospective cohort study.

Childhood predictors of self reported chronic fatigue syndrome/myalgic encephalomyelitis in adults: national birth cohort study.

Kinesiophobia in chronic fatigue syndrome: assessment and associations with disability.

The economic impact of chronic fatigue syndrome.

Chronic fatigue syndrome: matching exercise to symptom fluctuations.

Chronic fatigue syndrome in adolescents: a follow-up study.

Reduction of serotonin transporters of patients with chronic fatigue syndrome.

IgM serum antibodies to Epstein-Barr virus are uniquely present in a subset of patients with the chronic fatigue syndrome.

Posttraumatic stress disorder and physical illness: results from clinical and epidemiologic studies.

Association between chronic fatigue syndrome and the corticosteroid-binding globulin gene ALA SER224 polymorphism.

Prevalence of chronic disabling fatigue in children and adolescents.

Predictors of outcome in fatigued employees on sick leave: results from a randomised trial.

Physiological responses during a submaximal cycle test in chronic fatigue syndrome.

Disability evaluation in chronic fatigue syndrome: associations between exercise capacity and activity limitations/participation restrictions.

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