ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

3001–3020 of 6,209 studies

E2 ModerateCohortPEM unclearCase-Control

Chronic fatigue syndrome--a clinically empirical approach to its definition and study.

Reeves, William C, Wagner, Dieter, Nisenbaum, Rosane et al.·BMC medicine·2005

This study tested two different ways of diagnosing ME/CFS to see which one worked better. Researchers in Kansas recruited 227 people—some with ME/CFS, some with unexplained fatigue that didn't meet ME/CFS criteria, some depressed, and some healthy—and admitted them to a hospital for two days of testing. They found that a new method for diagnosing ME/CFS (based on measuring fatigue severity, disability, and symptoms) worked much better at identifying truly ill people than the old method.

Diagnostics

E2 ModerateCohortPEM unclearLongitudinal

Time course of exercise induced alterations in daily activity in chronic fatigue syndrome.

Black, Christopher D, McCully, Kevin K·Dynamic medicine : DM·2005

This study tracked how much physical activity people with ME/CFS could do while following a walking program. Participants wore activity monitors for 4 weeks. They were able to meet their daily walking goals for the first 1-2 weeks, but then their activity levels dropped significantly and symptoms got worse, suggesting they had hit a limit their bodies could not sustain.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCase-Control

Normal opioid tone and hypothalamic-pituitary-adrenal axis function in chronic fatigue syndrome despite marked functional impairment.

Inder, Warrick J, Prickett, Timothy C R, Mulder, Roger T·Clinical endocrinology·2005

This study tested whether ME/CFS is caused by low levels of pain-relieving chemicals (opioids) in the brain or problems with the stress hormone system. Researchers measured hormone levels and responses in 12 ME/CFS patients and 11 healthy people, and found no differences between the groups, suggesting these hormonal systems are working normally in ME/CFS despite severe fatigue and physical limitations.

Endocrine Disruption

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic Fatigue Syndrome: a survey of GPs' attitudes and knowledge.

Bowen, Jo, Pheby, Derek, Charlett, Andre et al.·Family practice·2005

This study asked general practitioners (GPs) in the UK what they knew about ME/CFS and how confident they felt diagnosing and treating it. About half of the GPs surveyed didn't feel confident making a diagnosis, and 41% didn't feel confident treating the condition. The study found that GPs who believed ME/CFS was a real medical condition had much more positive attitudes toward patients.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic fatigue syndrome: exercise performance related to immune dysfunction.

Nijs, Jo, Meeus, Mira, McGregor, Neil R et al.·Medicine and science in sports and exercise·2005

This study looked at whether problems with the immune system might explain why people with ME/CFS feel exhausted after exercise and cannot exercise as much as healthy people. Researchers tested 16 ME/CFS patients' immune cells and had them exercise on a stationary bike while measuring their oxygen use and heart rate. They found that two specific immune markers—elastase and protein kinase R—were linked to reduced exercise capacity, suggesting immune dysfunction may play a role in abnormal exercise responses.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

Ambulatory monitoring of physical activity and symptoms in fibromyalgia and chronic fatigue syndrome.

Kop, Willem J, Lyden, Angela, Berlin, Ali A et al.·Arthritis and rheumatism·2005

This study used activity trackers to measure how much people with ME/CFS and fibromyalgia move during daily life, and whether their pain and fatigue change based on activity levels. The researchers found that patients with these conditions did less intense activity and experienced more pain and fatigue when they were less active, but interestingly, having pain or fatigue seemed to cause them to reduce activity rather than the other way around.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCross-Sectional

Decreased dehydroepiandrosterone sulfate but normal insulin-like growth factor in chronic fatigue syndrome (CFS): relevance for the inflammatory response in CFS.

Maes, Michael, Mihaylova, Ivana, De Ruyter, Marcel·Neuro endocrinology letters·2005

This study compared hormone levels in people with ME/CFS to healthy controls. Researchers found that ME/CFS patients had significantly lower levels of DHEAS (a hormone made by the adrenal glands), but normal levels of another hormone called IGF1. The low DHEAS was closely linked to markers of immune system activation and inflammation, suggesting this hormone imbalance may contribute to ME/CFS symptoms.

Immune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

[A preliminary epidemiological study and discussion on traditional Chinese medicine pathogenesis of chronic fatigue syndrome in Hong Kong].

Yiu, Yan-Mun, Qiu, Ming-Yi·Zhong xi yi jie he xue bao = Journal of Chinese integrative medicine·2005

This study surveyed over 1,000 adults in Hong Kong to see how common ME/CFS is and how it appears according to traditional Chinese medicine (TCM) principles. Researchers found that about 6.4% of adults aged 20-50 met ME/CFS diagnostic criteria. According to TCM assessment, most patients showed patterns related to low energy reserves and poor circulation, with symptoms including fatigue, weak knees, poor sleep, and memory problems.

E2 ModerateBehavioralPEM not requiredLongitudinal

A 12-month follow-up study of self-management training for people with chronic disease: are changes maintained over time?

Barlow, J H, Wright, C C, Turner, A P et al.·British journal of health psychology·2005

This study followed 171 people with chronic illnesses (including ME/CFS) for 12 months after they completed a self-management training course. The improvements they experienced at 4 months—such as better fatigue management, increased confidence in managing their health, and improved mood—stayed the same at 12 months. People continued using the techniques they learned on the course.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

[Clinical characteristics of patients with chronic fatigue syndrome: analysis of 82 cases].

Li, Yong-Jie, Wang, De-Xin, Bai, Xiao-Li et al.·Zhonghua yi xue za zhi·2005

This study examined 82 Chinese patients with ME/CFS to understand what symptoms they experience and what might be causing their illness. Researchers found that most patients had memory and attention problems alongside fatigue, many showed signs of anxiety or depression, and some had low levels of a substance called L-carnitine (which helps produce energy) or evidence of a viral infection. When patients took L-carnitine supplements, their levels improved and symptoms got better.

Cognitive Impairment

E2 ModerateCohortPEM unclearCross-Sectional

Urinary and plasma organic acids and amino acids in chronic fatigue syndrome.

Jones, Mark G, Cooper, Elizabeth, Amjad, Saira et al.·Clinica chimica acta; international journal of clinical chemistry·2005

Researchers tested blood and urine samples from ME/CFS patients and compared them to healthy people, those with depression, and those with rheumatoid arthritis. Previous studies claimed certain chemicals in urine were markers for ME/CFS, but this study could not confirm those earlier findings. However, the study did find some signs of inflammation and possible muscle changes that might explain why ME/CFS patients experience fatigue and muscle pain.

Energy Metabolism

E2 ModerateCohortPEM not requiredCross-Sectional

Exercise capacity and immune function in male and female patients with chronic fatigue syndrome (CFS).

Snell, Christopher R, Vanness, J Mark, Strayer, David R et al.·In vivo (Athens, Greece)·2005

This study looked at whether a specific immune system problem affects how much exercise people with ME/CFS can do. Researchers tested 106 ME/CFS patients (35 men and 71 women) on exercise machines and found that patients with abnormal immune activity had noticeably lower exercise capacity than those with normal immune function. The difference was about the same for both men and women.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

The definition of disabling fatigue in children and adolescents.

Fowler, Tom, Duthie, Pamela, Thapar, Anita et al.·BMC family practice·2005

This study looked at how disabling fatigue in children and teens should be defined, since the current definition used for adults might not fit young people well. Researchers found that children with disabling fatigue that didn't quite meet the strict adult criteria still suffered just as much and missed just as much school as those who did meet the strict criteria. The study suggests that doctors should use a broader, less restrictive definition to catch all children who need help.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic fatigue in a population sample: definitions and heterogeneity.

Sullivan, Patrick F, Pedersen, Nancy L, Jacks, Andreas et al.·Psychological medicine·2005

This study looked at how doctors define ME/CFS by surveying over 31,000 Swedish adults about their fatigue symptoms. The researchers found that the current official checklist for diagnosing ME/CFS (requiring 4 out of 8 specific symptoms) doesn't match how fatigue actually varies in real populations. Using statistical analysis, they identified a recognizable ME/CFS-like illness pattern, but concluded that a simpler definition focusing on severe, disabling fatigue might work better.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

[Cognitive function and psychological characteristics of patients with chronic fatigue syndrome].

Li, Yong-jie, Gao, Xu-guang, Wang, De-Xin et al.·Zhonghua yi xue za zhi·2005

This study looked at how ME/CFS affects thinking and memory in 91 Chinese patients compared to 30 healthy people. Researchers found that 90% of ME/CFS patients had problems with memory and attention, and most also experienced depression, anxiety, and obsessive thoughts. The results show that ME/CFS causes real cognitive problems that are different from those seen in psychiatric illnesses alone.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Employment status in chronic fatigue syndrome. A cross-sectional study examining the value of exercise testing and self-reported measures for the assessment of employment status.

Nijs, Jo, Van de Putte, Karen, Louckx, Fred et al.·Clinical rehabilitation·2005

This study looked at whether exercise tests and questionnaires could predict which ME/CFS patients could work. Researchers tested 54 employed patients with ME/CFS and asked them about their work status and quality of life. They found that while some measures weakly related to employment, neither exercise testing nor self-reported disability measures were strong enough to reliably predict who could work.

E2 ModerateCohortPEM not requiredCase-Control

Orthostatic instability in a population-based study of chronic fatigue syndrome.

Jones, James F, Nicholson, Ainsley, Nisenbaum, Rosane et al.·The American journal of medicine·2005

This study tested whether people with ME/CFS have problems with their body's ability to regulate blood pressure and heart rate when changing positions (like standing up). Researchers compared 58 people with ME/CFS to 55 healthy people using a tilt table test. Surprisingly, they found that both groups had similar rates of these problems, suggesting that this particular type of autonomic dysfunction may not be a primary cause of ME/CFS.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Stress-induced changes in LPS-induced pro-inflammatory cytokine production in chronic fatigue syndrome.

Gaab, Jens, Rohleder, Nicolas, Heitz, Vera et al.·Psychoneuroendocrinology·2005

This study tested how ME/CFS patients' immune systems respond to stress compared to healthy people. Researchers gave both groups a stressful public speaking task, then exposed their blood samples to a bacterial substance to measure immune response. Unlike healthy controls whose immune response increased after stress, ME/CFS patients showed a decreased immune response, suggesting their bodies may not mobilize infection-fighting chemicals normally during stress.

Immune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome of childhood. Comparative study with emotional disorders.

Garralda, M Elena, Rangel, Luiza·European child & adolescent psychiatry·2005

This study compared children diagnosed with ME/CFS to children with emotional disorders like anxiety and depression to see how these conditions differ. While both groups of children experienced some similar emotional challenges, children with ME/CFS reported more severe tiredness and physical symptoms, and were more likely to have had infections or medical problems before getting sick. The results show that ME/CFS and emotional disorders can look similar in some ways but have important differences.

Diagnostics

E2 ModerateMechanismPEM requiredMechanistic

Exercise responsive genes measured in peripheral blood of women with chronic fatigue syndrome and matched control subjects.

Whistler, Toni, Jones, James F, Unger, Elizabeth R et al.·BMC physiology·2005

Researchers studied women with ME/CFS and compared them to healthy women to look for biological markers of post-exertional malaise (when activity makes symptoms worse). They measured how genes 'turn on and off' in blood cells before and after exercise. The study found that genes related to ion transport and cellular functions behave differently in ME/CFS patients after exercise compared to healthy people.

Post-Exertional Malaise

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Evidence browser

Chronic fatigue syndrome--a clinically empirical approach to its definition and study.

Time course of exercise induced alterations in daily activity in chronic fatigue syndrome.

Normal opioid tone and hypothalamic-pituitary-adrenal axis function in chronic fatigue syndrome despite marked functional impairment.

Chronic Fatigue Syndrome: a survey of GPs' attitudes and knowledge.

Chronic fatigue syndrome: exercise performance related to immune dysfunction.

Ambulatory monitoring of physical activity and symptoms in fibromyalgia and chronic fatigue syndrome.

Decreased dehydroepiandrosterone sulfate but normal insulin-like growth factor in chronic fatigue syndrome (CFS): relevance for the inflammatory response in CFS.

[A preliminary epidemiological study and discussion on traditional Chinese medicine pathogenesis of chronic fatigue syndrome in Hong Kong].

A 12-month follow-up study of self-management training for people with chronic disease: are changes maintained over time?

[Clinical characteristics of patients with chronic fatigue syndrome: analysis of 82 cases].

Urinary and plasma organic acids and amino acids in chronic fatigue syndrome.

Exercise capacity and immune function in male and female patients with chronic fatigue syndrome (CFS).

The definition of disabling fatigue in children and adolescents.

Chronic fatigue in a population sample: definitions and heterogeneity.

[Cognitive function and psychological characteristics of patients with chronic fatigue syndrome].

Employment status in chronic fatigue syndrome. A cross-sectional study examining the value of exercise testing and self-reported measures for the assessment of employment status.

Orthostatic instability in a population-based study of chronic fatigue syndrome.

Stress-induced changes in LPS-induced pro-inflammatory cytokine production in chronic fatigue syndrome.

Chronic fatigue syndrome of childhood. Comparative study with emotional disorders.

Exercise responsive genes measured in peripheral blood of women with chronic fatigue syndrome and matched control subjects.

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