ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

281–300 of 360 studies

E3 PreliminaryCohortPEM unclearCross-Sectional

Cerebral Blood Flow Is Reduced in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients During Mild Orthostatic Stress Testing: An Exploratory Study at 20 Degrees of Head-Up Tilt Testing.

van Campen, C Linda M C, Rowe, Peter C, Visser, Frans C·Healthcare (Basel, Switzerland)·2020

This study looked at blood flow to the brain in 19 people with severe ME/CFS who have difficulty standing up (orthostatic intolerance). When patients tilted their heads up at a mild 20-degree angle for 15 minutes, blood flow to their brains dropped by an average of 27%. All 19 patients showed this abnormal reduction in brain blood flow, suggesting this shorter, gentler test could help diagnose the condition even in the most severely ill patients who cannot tolerate longer or more intense tests.

Autonomic Nervous System

E3 PreliminaryReviewPEM unclearReview-Narrative

Mitochondria and immunity in chronic fatigue syndrome.

Anderson, G, Maes, M·Progress in neuro-psychopharmacology & biological psychiatry·2020

This review examines how problems with energy-producing structures in cells (mitochondria) and immune system dysfunction may contribute to ME/CFS. The authors propose that two key areas—the gut and immune cells—work together with the body's natural sleep-wake cycle to drive the condition. They also explore how factors like viral infections, gut bacteria, and hormones may play interconnected roles in ME/CFS symptoms.

Autonomic Nervous SystemImmune System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Clinical neurophysiology of postural tachycardia syndrome.

Cutsforth-Gregory, Jeremy K, Sandroni, Paola·Handbook of clinical neurology·2019

Postural tachycardia syndrome (POTS) is a condition where your heart rate jumps dramatically when you stand up, causing dizziness, lightheadedness, or other symptoms of not enough blood reaching your brain. It happens five times more often in women than men and can have several different causes, including problems with nerve signals, low blood volume, or deconditioning. Treatment focuses on helping patients stand longer and stay active, using approaches like drinking more fluids, wearing compression socks, and sometimes taking medications.

Autonomic Nervous System

E3 PreliminaryCohortPEM not requiredCase-Control

Postural orthostatic tachycardia syndrome (POTS): a common but unfamiliar syndrome.

van der Zalm, T, Alsma, J, van de Poll, S W E et al.·The Netherlands journal of medicine·2019

POTS is a condition where standing up quickly causes your heart to beat much faster than normal, and you may feel dizzy, tired, or unwell. This paper describes two different patients with POTS to show how differently the condition can appear from person to person. The authors explain that POTS can overlap with chronic fatigue syndrome and suggest that simple treatments like drinking more water and salt, along with exercise, often help before considering medications.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Managing fatigue in postural tachycardia syndrome (PoTS): The Newcastle approach.

Strassheim, Victoria, Welford, Jenny, Ballantine, Rob et al.·Autonomic neuroscience : basic & clinical·2018

This review examines fatigue in people with PoTS (postural tachycardia syndrome), a condition where heart rate increases abnormally when standing. The authors explain why fatigue happens in PoTS, how it overlaps with ME/CFS, and describe practical approaches doctors can use to help manage it by treating the individual causes of fatigue in each patient.

Autonomic Nervous System

E3 PreliminaryReviewPEM unclearReview-Narrative

HPV vaccination syndrome: A clinical mirage, or a new tragic fibromyalgia model.

Martínez-Lavín, Manuel·Reumatologia clinica·2018

Some people have reported developing chronic pain and autonomic symptoms (problems with heart rate, blood pressure, and sweating) after receiving the HPV vaccine. This article reviews whether this connection is real and suggests that if it exists, these cases might share similarities with fibromyalgia—a condition involving widespread pain and nervous system dysfunction. The authors propose that understanding fibromyalgia's mechanisms could help diagnose and treat patients who develop symptoms after HPV vaccination.

Pain and SensitizationAutonomic Nervous System

E3 PreliminaryMechanismPEM unclearObservational

Cardiac sympathetic innervation associates with autonomic dysfunction in chronic fatigue syndrome - a pilot study.

Petrides, George, Zalewski, Pawel, McCulloch, David et al.·Fatigue : biomedicine, health & behavior·2017

This study looked at how the nervous system controls the heart in people with ME/CFS, focusing on a specific part called the sympathetic nervous system. Researchers used specialized imaging to examine nerve connections in the heart and compared them to problems with autonomic function (the automatic nervous system that controls heart rate and blood pressure). The findings suggest that differences in heart nerve connections may be related to why some ME/CFS patients experience autonomic symptoms like dizziness and heart rate changes.

Autonomic Nervous System

E3 PreliminaryCohortPEM not requiredCase-Control

Sympathetic neural hyperalgesia edema syndrome as a cause of autoimmune hearing loss.

Check, J H·Clinical and experimental obstetrics & gynecology·2017

This case study describes one woman with ME/CFS, pelvic pain, and diarrhea who was given the stimulant medication dextroamphetamine to help with fertility. Unexpectedly, not only did her ME/CFS symptoms improve, but her hearing loss—which had not responded to months of steroid treatment—also significantly improved, as confirmed by hearing tests.

Autonomic Nervous System

E3 PreliminaryReviewPEM unclearReview-Narrative

Fibromyalgia syndrome pathology and environmental influences on afflictions with medically unexplained symptoms.

Albrecht, Phillip J, Rice, Frank L·Reviews on environmental health·2016

This review examines fibromyalgia syndrome (FMS) as a model for understanding conditions with symptoms that are difficult to explain medically. The authors discuss how nerve endings in the skin and stress hormones (particularly estrogen) may play a role in causing widespread pain and fatigue. They propose that environmental stress and past trauma can trigger changes in how the nervous system works, leading to increased pain sensitivity.

Autonomic Nervous System

E3 PreliminaryReviewPEM unclearReview-Narrative

TMD and chronic pain: a current view.

Furquim, Bruno D'Aurea, Flamengui, Lívia Maria Sales Pinto, Conti, Paulo César Rodrigues·Dental press journal of orthodontics·2015

This review examines how temporomandibular disorders (jaw joint and muscle problems) develop and persist. The authors found that chronic muscle pain in the jaw works similarly to other widespread pain conditions like fibromyalgia and ME/CFS—through a process called central sensitization where the nervous system becomes overly sensitive to pain signals. They explain that genetics and nervous system function influence whether symptoms improve or worsen.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Aspects of the non-pharmacological treatment of irritable bowel syndrome.

Eriksson, Elsa Maria, Andrén, Kristina Ingrid, Kurlberg, Göran Karl et al.·World journal of gastroenterology·2015

This article explains how irritable bowel syndrome (IBS) develops through problems in communication between the gut and brain, especially when the body is stressed or has experienced trauma. The authors suggest that combining traditional gastroenterology care with body-mind therapies—which help patients become more aware of their physical sensations—may be more effective than treating the gut alone.

Autonomic Nervous System

E3 PreliminaryCohortPEM not requiredCross-Sectional

HPV vaccination syndrome. A questionnaire-based study.

Martínez-Lavín, Manuel, Martínez-Martínez, Laura-Aline, Reyes-Loyola, Paola·Clinical rheumatology·2015

This study looked at people who developed long-lasting pain, fatigue, and heart/blood pressure problems shortly after receiving the HPV vaccine. Researchers used three validated questionnaires to assess 45 people from 13 countries. Most reported muscle pain, tiredness, and dizziness, and after an average of 4 years, 93% still had severe symptoms preventing them from working or going to school.

Pain and SensitizationAutonomic Nervous System

E3 PreliminaryReviewPEM unclearReview-Narrative

Neurovisceral phenotypes in the expression of psychiatric symptoms.

Eccles, Jessica A, Owens, Andrew P, Mathias, Christopher J et al.·Frontiers in neuroscience·2015

This review examines how physical differences in the body's automatic nervous system—the system that controls heart rate, blood pressure, and stress responses—may explain why some people experience anxiety more easily. The authors focus on three conditions: joint hypermobility (loose joints due to collagen differences), postural tachycardia syndrome (rapid heart rate when standing), and fainting with emotional stress. They propose that differences in how the brain controls these bodily functions may make people more vulnerable to anxiety and related conditions.

Autonomic Nervous System

E3 PreliminaryReviewPEM not requiredReview-Narrative

Postural Tachycardia Syndrome: Beyond Orthostatic Intolerance.

Garland, Emily M, Celedonio, Jorge E, Raj, Satish R·Current neurology and neuroscience reports·2015

This review explains postural tachycardia syndrome (POTS), a condition where your heart rate increases excessively when you stand up, often causing dizziness, fatigue, and other symptoms that improve when lying down. POTS can result from several different underlying problems—such as low blood volume, overactive stress nerves, or problems with small nerves in the legs—and may overlap with other conditions like ME/CFS. Treatment typically involves a combination of lifestyle changes, structured exercise, and sometimes medications.

Autonomic Nervous System

E3 PreliminaryMechanismPEM not requiredMechanistic

Phenylephrine alteration of cerebral blood flow during orthostasis: effect on n-back performance in chronic fatigue syndrome.

Medow, Marvin S, Sood, Shilpa, Messer, Zachary et al.·Journal of applied physiology (Bethesda, Md. : 1985)·2014

Many ME/CFS patients experience dizziness and cognitive problems when standing up because blood flow to the brain decreases. This study tested whether a medication called phenylephrine, which raises blood pressure, could help restore brain blood flow and improve thinking tasks during standing. The researchers found that phenylephrine reduced the brain blood flow drop and helped ME/CFS patients perform better on memory tests while upright.

Autonomic Nervous SystemCognitive Impairment

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 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 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 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 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

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Cerebral Blood Flow Is Reduced in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients During Mild Orthostatic Stress Testing: An Exploratory Study at 20 Degrees of Head-Up Tilt Testing.

Mitochondria and immunity in chronic fatigue syndrome.

Clinical neurophysiology of postural tachycardia syndrome.

Postural orthostatic tachycardia syndrome (POTS): a common but unfamiliar syndrome.

Managing fatigue in postural tachycardia syndrome (PoTS): The Newcastle approach.

HPV vaccination syndrome: A clinical mirage, or a new tragic fibromyalgia model.

Cardiac sympathetic innervation associates with autonomic dysfunction in chronic fatigue syndrome - a pilot study.

Sympathetic neural hyperalgesia edema syndrome as a cause of autoimmune hearing loss.

Fibromyalgia syndrome pathology and environmental influences on afflictions with medically unexplained symptoms.

TMD and chronic pain: a current view.

Aspects of the non-pharmacological treatment of irritable bowel syndrome.

HPV vaccination syndrome. A questionnaire-based study.

Neurovisceral phenotypes in the expression of psychiatric symptoms.

Postural Tachycardia Syndrome: Beyond Orthostatic Intolerance.

Phenylephrine alteration of cerebral blood flow during orthostasis: effect on n-back performance in chronic fatigue syndrome.

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

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

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

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

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

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