ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

281–300 of 345 studies

E3 PreliminaryBehavioralPEM not requiredCross-Sectional

Orthostatic responses in adolescent chronic fatigue syndrome: contributions from expectancies as well as gravity.

Wyller, Vegard Bruun, Fagermoen, Even, Sulheim, Dag et al.·BioPsychoSocial medicine·2014

When people with ME/CFS stand up or imagine standing, their body's nervous system responds differently than in healthy people. This study found that teenagers with ME/CFS have higher resting heart rate and blood pressure, and their nervous system shows stronger stress responses when they think about standing upright, even though their actual physical response to tilting was similar to healthy peers. This suggests that both the physical challenge of gravity and a person's expectations or anxiety about standing may contribute to the symptoms they experience.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

[Review of the effects of mindfulness meditation on mental and physical health and its mechanisms of action].

Ngô, Thanh-Lan·Sante mentale au Quebec·2013

This review looked at whether mindfulness meditation—a practice of focused attention and acceptance—can help improve both mental and physical health. The authors found that mindfulness may reduce stress, ease chronic pain and fatigue, improve sleep, and help the body's immune system work better. They also describe how meditation appears to change the way the brain works, particularly in areas that control emotions, attention, and how we perceive physical sensations.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Caught in the thickness of brain fog: exploring the cognitive symptoms of Chronic Fatigue Syndrome.

Ocon, Anthony J·Frontiers in physiology·2013

ME/CFS causes cognitive difficulties that patients often describe as "brain fog"—a feeling of foggy thinking, slow mental processing, and trouble concentrating. This review suggests brain fog may result from reduced blood flow to the brain combined with the physical stress of standing (which worsens symptoms in many patients), plus the extra mental effort required to complete tasks. Understanding these overlapping factors could help explain why cognitive symptoms feel so exhausting.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryReviewPEM requiredReview-Narrative

A neuro-immune model of Myalgic Encephalomyelitis/Chronic fatigue syndrome.

Morris, Gerwyn, Maes, Michael·Metabolic brain disease·2013

This study proposes a theory about how ME/CFS develops and persists. The researchers suggest that an initial infection triggers the immune system, which then gets stuck in an overactive state even after the infection is cleared. This causes ongoing inflammation, energy problems in cells, and damage to the nervous system, leading to the characteristic symptoms including post-exertional malaise (feeling worse after activity).

NeuroinflammationAutonomic Nervous SystemImmune SystemPost-Exertional Malaise

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Norepinephrine and epinephrine responses to physiological and pharmacological stimulation in chronic fatigue syndrome.

Strahler, Jana, Fischer, Susanne, Nater, Urs M et al.·Biological psychology·2013

This study looked at how the body's stress hormones (norepinephrine and epinephrine) respond in ME/CFS patients compared to healthy people. Researchers tested 21 ME/CFS patients and 20 controls using exercise and a hormone-stimulation test, measuring stress hormones before and after. ME/CFS patients showed weaker hormone responses to exercise, particularly lower baseline levels and blunted epinephrine release, which could help explain why physical activity feels so exhausting.

Autonomic Nervous System

E3 PreliminaryMechanismPEM not requiredMechanistic

Modulation of the axon-reflex response to local heat by reactive oxygen species in subjects with chronic fatigue syndrome.

Medow, Marvin S, Aggarwal, Arun, Baugham, Ila et al.·Journal of applied physiology (Bethesda, Md. : 1985)·2013

When skin is heated, blood vessels normally dilate to increase blood flow. This study found that people with ME/CFS have lower baseline blood flow in their skin compared to healthy people. When researchers used drugs to reduce harmful molecules called reactive oxygen species (particularly hydrogen peroxide), blood flow improved and the initial blood vessel response to heat increased in ME/CFS patients but not in healthy controls.

Pain and SensitizationAutonomic Nervous System

E3 PreliminaryReviewPEM unclearReview-Narrative

Brain dysfunction as one cause of CFS symptoms including difficulty with attention and concentration.

Natelson, Benjamin H·Frontiers in physiology·2013

This study suggests that ME/CFS is not one single disease but rather multiple conditions with different underlying causes. By grouping patients based on specific characteristics—like whether they have psychiatric diagnoses, fibromyalgia, or blood pressure problems when standing—researchers found that different groups showed different types of brain dysfunction. This approach could help explain why some patients experience trouble with concentration and attention in different ways.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryReviewPEM not requiredReview-Narrative

Neurocardiogenic syncope and associated conditions: insight into autonomic nervous system dysfunction.

Kossaify, Antoine, Kallab, Kamal·Turk Kardiyoloji Dernegi arsivi : Turk Kardiyoloji Derneginin yayin organidir·2013

This study examines why people faint or feel faint due to problems with their autonomic nervous system—the part of your nervous system that controls heart rate, blood pressure, and breathing automatically. The authors review how fainting episodes are connected to several conditions that ME/CFS patients often experience, including migraines, dizziness upon standing, rapid heartbeat with position changes, and chronic fatigue syndrome. They discuss how autonomic dysfunction may explain these related conditions.

Autonomic Nervous System

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Postural neurocognitive and neuronal activated cerebral blood flow deficits in young chronic fatigue syndrome patients with postural tachycardia syndrome.

Stewart, Julian M, Medow, Marvin S, Messer, Zachary R et al.·American journal of physiology. Heart and circulatory physiology·2012

When people with ME/CFS try to stand upright or tilt backward, their brain doesn't get enough blood flow to think clearly, and their thinking problems get worse as their body position changes. In healthy people, brain blood flow increases during hard thinking tasks, but in ME/CFS patients, this normal response is broken—their brains don't increase blood flow when doing difficult mental tasks.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryMechanismPEM not requiredObservational

Increasing orthostatic stress impairs neurocognitive functioning in chronic fatigue syndrome with postural tachycardia syndrome.

Ocon, Anthony J, Messer, Zachary R, Medow, Marvin S et al.·Clinical science (London, England : 1979)·2012

This study tested whether standing at increasing angles on a tilt table—a procedure that stresses the body's ability to maintain blood flow while upright—makes 'brain fog' worse in people with ME/CFS who also have POTS (a condition causing rapid heartbeat when standing). Researchers found that when people with CFS/POTS stood at steeper angles while doing concentration and memory tests, their performance got worse compared to healthy people, suggesting that orthostatic stress (the challenge of staying upright) does interfere with thinking and memory.

Autonomic Nervous SystemCognitive Impairment

E3 PreliminaryMechanismPEM not required

Clonidine in the treatment of adolescent chronic fatigue syndrome: a pilot study for the NorCAPITAL trial.

Fagermoen, Even, Sulheim, Dag, Winger, Anette et al.·BMC research notes·2012

This small study tested whether a blood pressure medication called clonidine could be safe and helpful for teenagers with ME/CFS. Five teenagers took a low dose of clonidine for two weeks, and researchers measured drug levels in their blood, how their hearts and blood pressure responded to position changes, and any side effects. The medication appeared safe with no serious problems, and it seemed to help improve their body's blood pressure responses.

Autonomic Nervous System

E3 PreliminaryCohortPEM not requiredObservational

Cervical neuro-muscular syndrome: discovery of a new disease group caused by abnormalities in the cervical muscles.

Matsui, Takayoshi, Ii, Kunio, Hojo, Shuntaro et al.·Neurologia medico-chirurgica·2012

This study suggests that problems in the neck muscles may cause or contribute to a range of symptoms including headaches, dizziness, fatigue, and autonomic problems (issues with automatic body functions like heart rate and blood pressure). The researchers treated patients with neck muscle abnormalities and reported that most patients improved significantly, with success rates ranging from 84-88% depending on the symptom.

Autonomic Nervous System

E3 PreliminaryMechanismPEM not requiredCross-Sectional

Blood pressure variability and closed-loop baroreflex assessment in adolescent chronic fatigue syndrome during supine rest and orthostatic stress.

Wyller, Vegard Bruun, Barbieri, Riccardo, Saul, J Philip·European journal of applied physiology·2011

This study looked at how the nervous system controls heart rate and blood pressure in teenagers with ME/CFS compared to healthy peers. Researchers found that teenagers with ME/CFS had less flexible blood pressure responses and their bodies shifted more toward 'fight or flight' nervous system activation when standing or experiencing mild stress, suggesting their autonomic nervous system (which controls these functions automatically) may not work as efficiently.

Autonomic Nervous System

E3 PreliminaryMechanismPEM not requiredCase-Control

Polymorphisms of adrenergic cardiovascular control genes are associated with adolescent chronic fatigue syndrome.

Sommerfeldt, Line, Portilla, Helene, Jacobsen, Line et al.·Acta paediatrica (Oslo, Norway : 1992)·2011

This study looked at genetic differences in genes that control how the body responds to stress and manages heart rate and blood pressure in teenagers with ME/CFS. Researchers found that people with ME/CFS were more likely to have certain genetic variations in two specific genes (COMT and the β₂-adrenergic receptor) compared to healthy people. These genetic differences may affect how well the body's autonomic nervous system (which controls automatic body functions) works during physical stress.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Neuroendocrine and immune contributors to fatigue.

Silverman, Marni N, Heim, Christine M, Nater, Urs M et al.·PM & R : the journal of injury, function, and rehabilitation·2010

This review explores how three body systems—the stress response system, the nervous system, and the immune system—may work together to cause the overwhelming tiredness experienced in ME/CFS. The researchers found that people with chronic fatigue often have an underactive stress-response system, an overactive fight-or-flight response, and immune system imbalances. Understanding how these systems interact may help explain why rest alone doesn't always resolve the fatigue.

Autonomic Nervous SystemImmune System

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

Efficiency evaluation of autonomic heart control by using the principal component analysis of ECG P-wave.

Krisciukaitis, A, Simoliuniene, R, Tamosiunas, M et al.·Methods of information in medicine·2010

This study developed a new computer method to measure how well the heart's nerves (autonomic nervous system) work by analyzing changes in the electrical activity of the heart during a simple tilt test, where a person moves from lying down to standing up. The researchers tested this method in healthy people and those with heart rhythm problems, and found it could detect differences in how the heart responds to position changes. This type of measurement might eventually help doctors diagnose problems with heart control earlier.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Pathogenic mechanisms of idiopathic nonallergic rhinitis.

Baraniuk, James N·The World Allergy Organization journal·2009

This study examines why some people develop chronic nasal symptoms like congestion and runny nose that don't have an obvious allergic cause. Researchers found that this condition may actually involve several different problems: structural issues in the nose, nerve sensitivity problems, and autonomic nervous system dysfunction—the same type of nervous system problem found in ME/CFS.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Can sustained arousal explain the Chronic Fatigue Syndrome?

Wyller, Vegard B, Eriksen, Hege R, Malterud, Kirsti·Behavioral and brain functions : BBF·2009

This study proposes that ME/CFS may be caused by the body getting stuck in a constant state of high alert, similar to being continuously stressed. This sustained arousal could develop after infections or emotional stress, especially in people with certain genetic traits or personality types. The researchers suggest this constant activation creates harmful cycles affecting the immune system, hormones, muscles, and thinking—ultimately leading to the overwhelming fatigue that defines ME/CFS.

Autonomic Nervous SystemImmune System

E3 PreliminaryReviewPEM unclearReview-Narrative

POTS versus deconditioning: the same or different?

Joyner, Michael J, Masuki, Shizue·Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2008

This review article compares POTS (a condition where heart rate and blood pressure drop abnormally when standing) with the physical deconditioning that happens after long bed rest or spaceflight. The authors suggest that both conditions may share similar causes and that carefully structured exercise training might help patients with POTS, ME/CFS, and fibromyalgia, while acknowledging the medical community must remain empathetic to patients with these complex conditions.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

[Autonomic function and child chronic fatigue syndrome].

Tanaka, Hidetaka·Nihon rinsho. Japanese journal of clinical medicine·2007

This review examined how the autonomic nervous system—the part of your nervous system that controls automatic functions like heart rate and blood pressure—might be involved in childhood ME/CFS. Researchers found that about one-third of children with ME/CFS had problems regulating their blood pressure and heart rate when standing up, a condition called orthostatic dysregulation. While some studies suggested increased sympathetic nervous system activity, the findings were not consistent across all research.

Autonomic Nervous System

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Orthostatic responses in adolescent chronic fatigue syndrome: contributions from expectancies as well as gravity.

[Review of the effects of mindfulness meditation on mental and physical health and its mechanisms of action].

Caught in the thickness of brain fog: exploring the cognitive symptoms of Chronic Fatigue Syndrome.

A neuro-immune model of Myalgic Encephalomyelitis/Chronic fatigue syndrome.

Norepinephrine and epinephrine responses to physiological and pharmacological stimulation in chronic fatigue syndrome.

Modulation of the axon-reflex response to local heat by reactive oxygen species in subjects with chronic fatigue syndrome.

Brain dysfunction as one cause of CFS symptoms including difficulty with attention and concentration.

Neurocardiogenic syncope and associated conditions: insight into autonomic nervous system dysfunction.

Postural neurocognitive and neuronal activated cerebral blood flow deficits in young chronic fatigue syndrome patients with postural tachycardia syndrome.

Increasing orthostatic stress impairs neurocognitive functioning in chronic fatigue syndrome with postural tachycardia syndrome.

Clonidine in the treatment of adolescent chronic fatigue syndrome: a pilot study for the NorCAPITAL trial.

Cervical neuro-muscular syndrome: discovery of a new disease group caused by abnormalities in the cervical muscles.

Blood pressure variability and closed-loop baroreflex assessment in adolescent chronic fatigue syndrome during supine rest and orthostatic stress.

Polymorphisms of adrenergic cardiovascular control genes are associated with adolescent chronic fatigue syndrome.

Neuroendocrine and immune contributors to fatigue.

Efficiency evaluation of autonomic heart control by using the principal component analysis of ECG P-wave.

Pathogenic mechanisms of idiopathic nonallergic rhinitis.

Can sustained arousal explain the Chronic Fatigue Syndrome?

POTS versus deconditioning: the same or different?

[Autonomic function and child chronic fatigue syndrome].

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