ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2420 studies

1941–1960 of 2,420 studies

E3 PreliminaryCohortPEM not requiredCase-Control

Orthostatic intolerance and chronic fatigue syndrome associated with Ehlers-Danlos syndrome.

Rowe, P C, Barron, D F, Calkins, H et al.·The Journal of pediatrics·1999

This study looked at 12 teenagers who had both ME/CFS and a connective tissue condition called Ehlers-Danlos syndrome (EDS). All of them also experienced problems with blood pressure and heart rate when standing up (orthostatic intolerance). The researchers found that abnormal connective tissue in blood vessels may cause blood to pool in the legs when standing, which could explain why these conditions often occur together.

Autonomic Nervous System

E3 PreliminaryPEM not required

Fatigue that doesn't go away.

Propsner, N M·New Jersey medicine : the journal of the Medical Society of New Jersey·1999

This article describes chronic fatigue syndrome (ME/CFS), a condition where people experience extreme tiredness that doesn't improve with rest. The fatigue often begins after a viral infection and is more commonly seen in middle-aged women. While current treatments can help manage symptoms, researchers are working to better understand the condition and develop more effective approaches.

Interventions

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Corticomotor excitability and perception of effort during sustained exercise in the chronic fatigue syndrome.

Sacco, P, Hope, P A, Thickbroom, G W et al.·Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology·1999

This study examined whether the fatigue and exercise difficulty in ME/CFS comes from the brain and nervous system rather than just muscle weakness. Researchers used magnetic stimulation to measure how the motor cortex (the brain region controlling movement) responds during sustained muscle contractions in ME/CFS patients and healthy controls. They found that people with ME/CFS had shorter exercise endurance, felt more exhausted during effort, and showed different patterns of brain-to-muscle signaling compared to healthy people.

Post-Exertional Malaise

E3 PreliminaryBehavioralPEM not requiredObservational

Toward a model of social course in chronic illness: the example of chronic fatigue syndrome.

Ware, N C·Culture, medicine and psychiatry·1999

This study looked at how ME/CFS affects people's social lives by collecting personal stories from patients. The researchers found that ME/CFS can push people to the margins of their social worlds through processes like losing roles, being doubted or not believed, becoming isolated, and losing opportunities. However, patients also fight back and try to stay connected to their communities. The study shows that people's place in society moves back and forth depending on whether these isolating forces or connection efforts are stronger at any given time.

E3 PreliminaryReviewPEM not requiredReview-Narrative

The role of tryptophan in fatigue in different conditions of stress.

Castell, L M, Yamamoto, T, Phoenix, J et al.·Advances in experimental medicine and biology·1999

This study looks at tryptophan, a building block the brain uses to make serotonin, a chemical involved in fatigue and sleep. The researchers measured tryptophan levels in ME/CFS patients and people recovering from surgery, comparing how their bodies handled tryptophan differently than healthy controls. They found that ME/CFS patients had unusually high tryptophan levels that didn't change with exercise, which might help explain why they feel persistently tired.

E3 PreliminaryMechanismPEM not requiredMechanistic

Impaired oxygen delivery to muscle in chronic fatigue syndrome.

McCully, K K, Natelson, B H·Clinical science (London, England : 1979)·1999

This study found that muscles in people with ME/CFS are not receiving oxygen as quickly and efficiently as they should after exercise or when blood flow is temporarily stopped. The researchers measured how fast oxygen returns to calf muscles and found it took significantly longer in ME/CFS patients compared to healthy people. They also found that the muscles' ability to use oxygen for energy was reduced by about 20% in ME/CFS patients.

Post-Exertional Malaise

E3 PreliminaryCommentaryPEM not requiredEditorial

Functional somatic syndromes.

Barsky, A J, Borus, J F·Annals of internal medicine·1999

This 1999 editorial discusses how several chronic conditions—including ME/CFS, fibromyalgia, and irritable bowel syndrome—share common features: they cause real suffering and disability, but standard medical tests often don't find clear tissue damage. The authors suggest that a self-reinforcing cycle develops where patients become convinced they have a serious disease, their symptoms worsen over time, and this belief itself amplifies their suffering, even when psychological and social factors play a role.

E3 PreliminaryCohortPEM unclearCase-Control

Detailed description of a pregnancy associated with severe chronic fatigue syndrome.

Jha, R R, Masson, E A, Lindow, S W·Journal of obstetrics and gynaecology : the journal of the Institute of Obstetrics and Gynaecology·1999

This is a detailed case report describing one woman's experience with severe ME/CFS during pregnancy. The report documents how her condition changed during pregnancy and what medical care she received. While this is just one person's story rather than a study comparing many patients, it provides valuable insight into what pregnancy can be like for someone with severe ME/CFS.

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

DISCERN: an instrument for judging the quality of written consumer health information on treatment choices.

Charnock, D, Shepperd, S, Needham, G et al.·Journal of epidemiology and community health·1999

This study created DISCERN, a tool that helps patients and healthcare providers evaluate whether written information about medical treatments is accurate and trustworthy. Researchers tested the tool on health information about three conditions, including chronic fatigue syndrome (now called ME/CFS), to see if different people using it would reach similar conclusions about quality. The tool consists of 15 questions and works best when used by people with training or experience in healthcare information.

E3 PreliminaryCohortPEM not requiredObservational

A pilot study employing Dehydroepiandrosterone (DHEA) in the treatment of chronic fatigue syndrome.

Himmel, P B, Seligman, T M·Journal of clinical rheumatology : practical reports on rheumatic & musculoskeletal diseases·1999

This study tested whether giving DHEA (a hormone supplement) could help ME/CFS patients who had low DHEA levels. Researchers found that 23 women taking DHEA for 6 months experienced improvements in pain, fatigue, anxiety, memory, and thinking. However, this was a small, uncontrolled study, so larger, more rigorous trials are needed to confirm these results.

Endocrine Disruption

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic fatigue syndrome: a hypothesis focusing on the autonomic nervous system.

Pagani, M, Lucini, D·Clinical science (London, England : 1979)·1999

This study looked at whether ME/CFS might be caused by problems with the autonomic nervous system—the part of your nervous system that controls automatic functions like heart rate and blood pressure. The researchers measured how the heart's electrical activity varied in ME/CFS patients and found signs suggesting their nervous systems were stuck in a 'revved up' state at rest but didn't respond normally to challenges.

Autonomic Nervous System

E3 PreliminaryBehavioralPEM not requiredCase-Control

Nefazodone for patients with chronic fatigue syndrome.

Hickie, I·The Australian and New Zealand journal of psychiatry·1999

This small study looked at whether a medication called nefazodone could help ME/CFS patients feel better. Ten patients took the drug and also received advice about sleep and behavioral strategies. Most patients reported some improvement in tiredness, sleep problems, and mood, and half were able to return to work or their normal activities.

Sleep

E3 PreliminaryMechanismPEM not requiredMechanistic

Stealth adaptation of an African green monkey simian cytomegalovirus.

Martin, W J·Experimental and molecular pathology·1999

Researchers found genetic material from a virus in a patient with chronic fatigue syndrome that resembles human cytomegalovirus (a common virus). Interestingly, the virus was missing genes that the immune system normally recognizes and attacks, which might allow it to hide from immune defenses. Genetic analysis showed this virus actually came from African green monkeys, not humans.

Immune System

E3 PreliminaryCohortPEM not requiredObservational

Chronic fatigue syndrome among overseas development workers: A qualitative study.

Lovell, D M·Journal of travel medicine·1999

This study interviewed 12 overseas development workers who developed ME/CFS while working abroad or shortly after visiting projects. Most felt they had been very healthy before getting sick, and they described typical ME/CFS symptoms like fatigue and pain. The researchers found that participants believed their illness was caused by a combination of overwork, stress, and infections—not depression.

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Cortical motor potential alterations in chronic fatigue syndrome.

Gordon, R, Michalewski, H J, Nguyen, T et al.·International journal of molecular medicine·1999

Researchers measured electrical brain activity in people with ME/CFS while they performed tasks like responding to targets, remembering information, and moving on command. They found that people with ME/CFS were slower at these tasks and showed weaker brain signals before moving, suggesting their brains may prepare for movement differently. However, their brains processed sensory information and made decisions normally.

Cognitive Impairment

E3 PreliminaryGuidelinePEM not requiredGuideline

Investigating fatigue of less than 6 months' duration. Guidelines for family physicians.

Godwin, M, Delva, D, Miller, K et al.·Canadian family physician Medecin de famille canadien·1999

This guideline helps family doctors systematically evaluate adults who come to them complaining of fatigue lasting less than 6 months. Rather than ordering many expensive tests, the guidelines recommend doctors first talk with patients about their symptoms and do a physical exam, paying special attention to psychological and social factors that might cause tiredness. The guideline then tells doctors which tests to consider based on what they find.

E3 PreliminaryCohortPEM not requiredObservational

Acute effects of thirty minutes of light-intensity, intermittent exercise on patients with chronic fatigue syndrome.

Clapp, L L, Richardson, M T, Smith, J F et al.·Physical therapy·1999

This study looked at whether 30 minutes of light, on-and-off walking on a treadmill would make symptoms worse in people with ME/CFS. Ten participants did 10 short 3-minute walks with 3-minute rest breaks in between. The researchers found that this type of gentle, intermittent exercise did not worsen symptoms immediately or up to a week afterward.

Post-Exertional Malaise

E3 PreliminaryPEM not requiredRegistry-Resource

The Chronic Fatigue Twin Registry: method of construction, composition, and zygosity assignment.

Buchwald, D, Herrell, R, Ashton, S et al.·Twin research : the official journal of the International Society for Twin Studies·1999

Researchers created a registry of twin pairs where at least one person had chronic fatigue to better understand the condition. They recruited 204 twin pairs through support groups, doctors, and other sources, and had 177 complete their detailed questionnaires and phone interviews. This registry was designed to help scientists study what causes chronic fatigue and whether genetics or life circumstances play a bigger role.

Diagnostics

E3 PreliminaryReviewPEM unclearReview-Narrative

Is fibromyalgia a distinct clinical entity? Historical and epidemiological evidence.

Wessely, S, Hotopf, M·Bailliere's best practice & research. Clinical rheumatology·1999

This research article examines whether fibromyalgia is truly a separate disease or whether it's actually similar to other conditions like ME/CFS, irritable bowel syndrome, and chronic chest pain. The authors reviewed historical records, clinical observations, and population-level data and concluded that fibromyalgia shares many features with other unexplained illnesses rather than being completely distinct.

E3 PreliminaryGuidelinePEM not requiredGuideline

[Symptomatic and concurrent depressions].

Terra, J L·La Revue du praticien·1999

This paper explains that when people have depression, they often also have other mental health or physical health problems at the same time. Examples include anxiety disorders, alcohol use problems, eating disorders, and medical conditions like heart disease, cancer, and chronic fatigue syndrome. The authors provide guidance to help doctors decide which condition to treat first when someone has multiple problems occurring together.

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Orthostatic intolerance and chronic fatigue syndrome associated with Ehlers-Danlos syndrome.

Fatigue that doesn't go away.

Corticomotor excitability and perception of effort during sustained exercise in the chronic fatigue syndrome.

Toward a model of social course in chronic illness: the example of chronic fatigue syndrome.

The role of tryptophan in fatigue in different conditions of stress.

Impaired oxygen delivery to muscle in chronic fatigue syndrome.

Functional somatic syndromes.

Detailed description of a pregnancy associated with severe chronic fatigue syndrome.

DISCERN: an instrument for judging the quality of written consumer health information on treatment choices.

A pilot study employing Dehydroepiandrosterone (DHEA) in the treatment of chronic fatigue syndrome.

Chronic fatigue syndrome: a hypothesis focusing on the autonomic nervous system.

Nefazodone for patients with chronic fatigue syndrome.

Stealth adaptation of an African green monkey simian cytomegalovirus.

Chronic fatigue syndrome among overseas development workers: A qualitative study.

Cortical motor potential alterations in chronic fatigue syndrome.

Investigating fatigue of less than 6 months' duration. Guidelines for family physicians.

Acute effects of thirty minutes of light-intensity, intermittent exercise on patients with chronic fatigue syndrome.

The Chronic Fatigue Twin Registry: method of construction, composition, and zygosity assignment.

Is fibromyalgia a distinct clinical entity? Historical and epidemiological evidence.

[Symptomatic and concurrent depressions].

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