ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

3021–3040 of 6,160 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Sleep assessment in a population-based study of chronic fatigue syndrome.

Unger, Elizabeth R, Nisenbaum, Rosane, Moldofsky, Harvey et al.·BMC neurology·2004

This study looked at sleep problems in 339 people with ME/CFS from Kansas to understand how sleep issues relate to their fatigue. Researchers found that over 80% of ME/CFS patients had at least one sleep problem, with non-restorative sleep (sleep that doesn't feel refreshing) and restlessness being the most common. Interestingly, ME/CFS patients were not unusually sleepy during the day, which suggests their fatigue comes from a different mechanism than typical sleep deprivation.

Sleep

E2 ModerateCohortPEM not requiredCase-Control

Monozygotic twins discordant for chronic fatigue syndrome: objective measures of sleep.

Ball, Nigel, Buchwald, Dedra S, Schmidt, Douglas et al.·Journal of psychosomatic research·2004

This study compared sleep patterns between people with ME/CFS and their healthy identical twins using objective sleep monitoring. While people with ME/CFS showed some differences—including more deep sleep, more REM sleep, and more breathing interruptions during sleep—most standard sleep measurements were similar between the two groups. The researchers concluded that sleep structure problems alone don't fully explain why ME/CFS patients experience such severe sleep complaints.

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 ModerateCohortPEM not requiredCross-Sectional

Sociodemographic and symptom correlates of fatigue in an adolescent primary care sample.

Mears, Cynthia J, Taylor, Renee R, Jordan, Karen M et al.·The Journal of adolescent health : official publication of the Society for Adolescent Medicine·2004

This study looked at how common fatigue lasting more than one month is in teenagers visiting primary care clinics. Researchers found that about 8% of teens had prolonged fatigue and 4.4% had symptoms matching CFS-like illness. Teens with prolonged fatigue were more likely to also experience headaches, muscle pain, fever, and fatigue that worsened with exercise.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Factors influencing the diagnosis of chronic fatigue syndrome.

Solomon, Laura, Reeves, William C·Archives of internal medicine·2004

Researchers in Wichita, Kansas identified people with ME/CFS symptoms from the general population and found that only 16% had ever been diagnosed with the condition by a doctor. People were more likely to have received a diagnosis if they had moderate income, developed fatigue suddenly, or had tender lymph nodes and sore throat. This suggests that most people with ME/CFS in the community are never formally diagnosed.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Factor analysis of symptoms among subjects with unexplained chronic fatigue: what can we learn about chronic fatigue syndrome?

Nisenbaum, Rosane, Reyes, Michele, Unger, Elizabeth R et al.·Journal of psychosomatic research·2004

This study looked at 1,391 people with unexplained chronic fatigue to understand which symptoms tend to occur together. Researchers found that ME/CFS symptoms cluster into three main groups: muscle and joint pain, infection-like symptoms, and problems with thinking, mood, and sleep. Interestingly, people with and without an ME/CFS diagnosis had significant overlap in these symptoms, suggesting that ME/CFS exists on a spectrum rather than as a completely distinct condition.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Study of immune alterations in patients with chronic fatigue syndrome with different etiologies.

Racciatti, D, Dalessandro, M, Delle Donne, L et al.·International journal of immunopathology and pharmacology·2004

This study looked at immune system cells in people with ME/CFS to see if there were differences compared to healthy people. Researchers tested blood samples from 139 ME/CFS patients and 36 healthy controls, examining specific types of white blood cells. They found that people with ME/CFS had lower counts of certain immune cells, suggesting the immune system may play a role in causing or maintaining the condition.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Patterns of cardiovascular reactivity in disease diagnosis.

Naschitz, J E, Rosner, I, Rozenbaum, M et al.·QJM : monthly journal of the Association of Physicians·2004

This study looked at how the heart and blood vessels respond to changes in body position (lying down versus standing up) in people with ME/CFS compared to healthy people and those with other conditions. Researchers used a simple test where patients lie down and then tilt upright while measuring heart rate and blood vessel changes. They found that people with ME/CFS have a distinctive pattern of heart and blood vessel responses that could help doctors identify the condition.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredLongitudinal

Development of the chronic fatigue syndrome in severely fatigued employees: predictors of outcome in the Maastricht cohort study.

Huibers, Marcus J H, Kant, I Jmert, Knottnerus, J André et al.·Journal of epidemiology and community health·2004

This study followed over 1,100 Dutch workers who reported unexplained fatigue for 3.7 years to see who would develop ME/CFS and who would recover. About 8% developed ME/CFS-like illness, 40% continued to have fatigue without meeting ME/CFS criteria, and 52% recovered completely. The study found that people at higher risk of developing ME/CFS tended to be older, female, less educated, and reported feeling exhausted and in poor health.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Post-traumatic stress disorder among patients with chronic pain and chronic fatigue.

Roy-Byrne, P, Smith, W R, Goldberg, J et al.·Psychological medicine·2004

This study examined whether trauma and PTSD are more common in people with fibromyalgia and chronic fatigue syndrome. Researchers found that among 571 patients, about 20% had experienced PTSD and 42% had depression. The link between fibromyalgia symptoms (pain and tender points) and PTSD was strongest in patients who also had depression, suggesting that depression may play an important role in how trauma and chronic pain conditions are connected.

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 ModerateCohortPEM unclearCross-Sectional

Working memory deficits in chronic fatigue syndrome: differentiating between speed and accuracy of information processing.

Deluca, John, Christodoulou, Christopher, Diamond, Bruce J et al.·Journal of the International Neuropsychological Society : JINS·2004

This study tested how quickly people with ME/CFS can process information (like reading or hearing something fast) and how well they can hold information in their working memory (like remembering a phone number while writing it down). The researchers found that people with ME/CFS without mental health conditions had slower information processing speeds, but their memory ability was normal. Interestingly, people with ME/CFS who also had depression or anxiety showed similar results to healthy people.

Cognitive Impairment

E2 ModerateCohortPEM not requiredObservational

A comparison of pregnancies that occur before and after the onset of chronic fatigue syndrome.

Schacterle, Richard S, Komaroff, Anthony L·Archives of internal medicine·2004

This study surveyed 86 women with ME/CFS about their pregnancies before and after developing the illness. During pregnancy, about 4 in 10 women had no change in symptoms, 3 in 10 improved, and 3 in 10 worsened. The study found that pregnancy itself did not consistently make ME/CFS worse, and most pregnancy outcomes were similar whether the illness was present or not, though miscarriage rates were higher in pregnancies after ME/CFS onset.

E2 ModerateCohortPEM not requiredCross-Sectional

Associations between neuroendocrine responses to the Insulin Tolerance Test and patient characteristics in chronic fatigue syndrome.

Gaab, Jens, Engert, Veronika, Heitz, Vera et al.·Journal of psychosomatic research·2004

This study tested whether ME/CFS patients have problems with their stress hormone system (the HPA axis). Researchers gave 18 ME/CFS patients and 17 healthy controls a special test that triggers the body's stress response and measured their hormones. They found that ME/CFS patients had a weaker hormone response, and this weakness was linked to how long someone had been sick and how severe their fatigue was.

Endocrine Disruption

E2 ModerateBehavioralPEM not requiredCross-Sectional

Impairment and coping in children and adolescents with chronic fatigue syndrome: a comparative study with other paediatric disorders.

Garralda, M Elena, Rangel, Luiza·Journal of child psychology and psychiatry, and allied disciplines·2004

This study compared how much ME/CFS affects children's daily lives compared to other conditions like arthritis and emotional disorders. Children with ME/CFS had more severe problems with school attendance and were more worried about their illness than the other groups. The study found that children with ME/CFS used different coping strategies—they were less likely to solve problems actively and more likely to give up or regulate their emotions when dealing with illness.

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 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

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 unclearCase-Control

Prevalence of abnormal cardiac wall motion in the cardiomyopathy associated with incomplete multiplication of Epstein-barr Virus and/or cytomegalovirus in patients with chronic fatigue syndrome.

Lerner, A Martin, Dworkin, Howard J, Sayyed, Tawfeeq et al.·In vivo (Athens, Greece)·2004

This study examined whether certain ME/CFS patients have heart problems caused by incomplete viral infections with Epstein-Barr virus or cytomegalovirus. Researchers found that ME/CFS patients with specific viral antibodies in their blood were more likely to show abnormal heart wall movement compared to control patients without ME/CFS. Some ME/CFS patients even showed heart tissue damage (cardiomyopathy) on biopsy.

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

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Sleep assessment in a population-based study of chronic fatigue syndrome.

Monozygotic twins discordant for chronic fatigue syndrome: objective measures of sleep.

Prevalence of chronic disabling fatigue in children and adolescents.

Sociodemographic and symptom correlates of fatigue in an adolescent primary care sample.

Factors influencing the diagnosis of chronic fatigue syndrome.

Factor analysis of symptoms among subjects with unexplained chronic fatigue: what can we learn about chronic fatigue syndrome?

Study of immune alterations in patients with chronic fatigue syndrome with different etiologies.

Patterns of cardiovascular reactivity in disease diagnosis.

Development of the chronic fatigue syndrome in severely fatigued employees: predictors of outcome in the Maastricht cohort study.

Post-traumatic stress disorder among patients with chronic pain and chronic fatigue.

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

Working memory deficits in chronic fatigue syndrome: differentiating between speed and accuracy of information processing.

A comparison of pregnancies that occur before and after the onset of chronic fatigue syndrome.

Associations between neuroendocrine responses to the Insulin Tolerance Test and patient characteristics in chronic fatigue syndrome.

Impairment and coping in children and adolescents with chronic fatigue syndrome: a comparative study with other paediatric disorders.

The economic impact of chronic fatigue syndrome.

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

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

Prevalence of abnormal cardiac wall motion in the cardiomyopathy associated with incomplete multiplication of Epstein-barr Virus and/or cytomegalovirus in patients with chronic fatigue syndrome.

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

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