ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

121–140 of 349 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Hemodynamics during the 10-minute NASA Lean Test: evidence of circulatory decompensation in a subset of ME/CFS patients.

Lee, Jihyun, Vernon, Suzanne D, Jeys, Patricia et al.·Journal of translational medicine·2020

This study tested a simple 10-minute standing test called the NASA Lean Test in ME/CFS patients to understand heart and blood vessel problems that cause dizziness and weakness. Researchers found that patients who became sick more recently (within 4 years) showed signs of circulation problems during the test—their hearts beat faster and their blood pressure changed abnormally—while those sick for over 10 years showed fewer of these changes. The NASA Lean Test appears to be a useful tool that doctors can use to diagnose and monitor these circulation problems.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Impairments in cognitive performance in chronic fatigue syndrome are common, not related to co-morbid depression but do associate with autonomic dysfunction.

Robinson, Lucy J, Gallagher, Peter, Watson, Stuart et al.·PloS one·2019

This study found that people with ME/CFS often experience slowing in thinking speed and processing information, particularly in tasks requiring quick reactions. Importantly, these cognitive difficulties are not caused by depression—even patients without depression showed the same thinking problems. The researchers discovered that problems with heart rate regulation (how the body's autonomic nervous system works) were linked to these cognitive difficulties.

Autonomic Nervous SystemCognitive Impairment

E2 ModerateBehavioralPEM not requiredLongitudinal

Fatigue in Epstein-Barr virus infected adolescents and healthy controls: A prospective multifactorial association study.

Pedersen, Maria, Asprusten, Tarjei Tørre, Godang, Kristin et al.·Journal of psychosomatic research·2019

This study followed teenagers with acute Epstein-Barr virus (EBV) infection and compared them to healthy teenagers to understand what causes fatigue. Researchers measured 148 different factors including symptoms, quality of life, sleep, emotions, immune markers, and heart rate control at the start of infection and again six months later. They found that fatigue was consistently linked to sleep problems, negative emotions, and poor quality of life, but surprisingly, markers of active infection were not associated with how tired people felt.

SleepAutonomic Nervous System

E2 ModerateCohortPEM not requiredObservational

A cluster analysis of serious adverse event reports after human papillomavirus (HPV) vaccination in Danish girls and young women, September 2009 to August 2017.

Ward, Daniel, Thorsen, Nicklas Myrthue, Frisch, Morten et al.·Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin·2019

This study examined adverse event reports submitted to Danish health authorities after HPV vaccination between 2009 and 2017. Researchers found that fatigue, dizziness, and headache were common symptoms reported, and noticed that some clusters of reports—particularly those mentioning cognitive problems and sleep issues—were submitted during periods of increased media coverage about vaccine safety concerns.

Autonomic Nervous SystemCognitive Impairment

E2 ModerateCohortPEM unclearLongitudinal

Long Term Follow up of Young People With Chronic Fatigue Syndrome Attending a Pediatric Outpatient Service.

Rowe, Katherine S·Frontiers in pediatrics·2019

This study followed 784 young people with ME/CFS for an average of 8 years to understand how the illness progresses over time. About half of the young people reported recovery within 5 years, and by 10 years, 68% reported feeling recovered. Most young people improved in their ability to function daily, though a small group (5%) remained very unwell. Having supportive doctors, staying involved in school with flexible accommodations, and developing personal management plans were all important for long-term improvement.

Autonomic Nervous System

E2 ModerateCohortPEM unclearObservational

Relationship Between Exercise-induced Oxidative Stress Changes and Parasympathetic Activity in Chronic Fatigue Syndrome: An Observational Study in Patients and Healthy Subjects.

Polli, Andrea, Van Oosterwijck, Jessica, Nijs, Jo et al.·Clinical therapeutics·2019

This study looked at whether oxidative stress (cellular damage from normal metabolism) is related to pain in ME/CFS patients, and how it connects to the vagus nerve, which helps control the body's relaxation response. Researchers had ME/CFS patients and healthy people do a mild exercise test and measured their pain, oxidative stress levels, and nerve activity before and after. They found that oxidative stress was linked to pain in ME/CFS patients, but unlike healthy people, ME/CFS patients didn't show improvements in pain or oxidative stress after exercise.

Pain and SensitizationAutonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Associations Between Autonomic and Orthostatic Self-report and Physician Ratings of Orthostatic Intolerance in Youth.

Schultz, Katlin R, Katz, Ben Z, Bockian, Neil R et al.·Clinical therapeutics·2019

This study looked at whether what young people with ME/CFS report feeling about dizziness and heart symptoms matches what doctors measure during physical exams. Researchers compared answers from questionnaires with actual measurements of blood pressure and heart rate changes. They found that while patients reported these symptoms, the physical measurements didn't always show the same problems, suggesting current testing methods may miss real autonomic problems in young ME/CFS patients.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Orthostatic intolerance in chronic fatigue syndrome.

Garner, Richard, Baraniuk, James N·Journal of translational medicine·2019

This study looked at dizziness and lightheadedness symptoms in ME/CFS patients when lying down versus standing up. Researchers found that these symptoms were very common in ME/CFS (occurring in 72% of patients when standing) and that they often happened even while lying down—something doctors don't usually check for. Importantly, these symptoms weren't simply caused by a rapid heart rate, suggesting a different mechanism is at play in ME/CFS.

Autonomic Nervous System

E2 ModerateCohortPEM unclear

Autonomic dysfunction in myalgic encephalomyelitis and chronic fatigue syndrome: comparing self-report and objective measures.

Kemp, Jane, Sunnquist, Madison, Jason, Leonard A et al.·Clinical autonomic research : official journal of the Clinical Autonomic Research Society·2019

This study looked at whether ME/CFS patients experience problems with their autonomic nervous system—the part that controls heart rate, blood pressure, and other automatic body functions. The researchers compared what patients reported about their symptoms with objective medical tests to see if these matched up, helping doctors understand this aspect of ME/CFS better.

Autonomic Nervous System

E2 ModerateCohortPEM unclearObservational

Low Sensitivity of Abbreviated Tilt Table Testing for Diagnosing Postural Tachycardia Syndrome in Adults With ME/CFS.

van Campen, C Linda M C, Rowe, Peter C, Visser, Frans C·Frontiers in pediatrics·2018

Many people with ME/CFS experience dizziness and rapid heartbeat when standing up, a condition called POTS. This study found that when doctors use shortened tilt table tests (lasting only 2 minutes) to diagnose POTS, they miss more than half of the patients who actually have it. The researchers recommend using the full 10-minute test instead of the abbreviated version to properly identify POTS in ME/CFS patients.

Autonomic Nervous System

E2 ModerateCohortPEM unclearObservational

Verification of exercise-induced transient postural tachycardia phenotype in Gulf War Illness.

Garner, Richard S, Rayhan, Rakib U, Baraniuk, James N·American journal of translational research·2018

Researchers found that about one-fourth of Gulf War Illness patients developed an unusual heart rate response after exercise: their heart raced when they stood up, even though this didn't happen before exercise. This temporary condition, called the START phenotype, appeared around 2 hours after exercise and was different from a similar condition called POTS that some patients had continuously. This discovery suggests that exercise can trigger a specific cardiovascular problem in some Gulf War Illness patients.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Intracranial compliance is associated with symptoms of orthostatic intolerance in chronic fatigue syndrome.

Finkelmeyer, Andreas, He, Jiabao, Maclachlan, Laura et al.·PloS one·2018

Many people with ME/CFS experience dizziness or lightheadedness when standing up—a condition called orthostatic intolerance. This study used brain imaging to measure how well the brain's blood vessels and fluid systems adjust to position changes. Researchers found that ME/CFS patients with worse symptoms had less flexible brain spaces and higher blood flow at rest, suggesting their brains may struggle to maintain proper blood flow when standing.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Circadian rhythm abnormalities and autonomic dysfunction in patients with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis.

Cambras, Trinitat, Castro-Marrero, Jesús, Zaragoza, Maria Cleofé et al.·PloS one·2018

This study compared daily activity patterns and skin temperature regulation in 10 women with ME/CFS and 10 healthy women over a week in both winter and summer. While sleep patterns were similar between groups, people with ME/CFS had lower overall daily activity levels and their bodies showed weaker responses to the normal daily rhythm patterns that healthy people display (like a post-lunch energy dip). The findings suggest that ME/CFS may involve problems with how the body's internal clock and temperature regulation systems work.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Poor self-reported sleep quality and health-related quality of life in patients with chronic fatigue syndrome/myalgic encephalomyelitis.

Castro-Marrero, Jesús, Zaragozá, Maria C, González-Garcia, Sergio et al.·Journal of sleep research·2018

This study looked at sleep problems in 1,455 Spanish ME/CFS patients and found that nearly all of them reported poor sleep quality that wasn't refreshing, even when they slept. The researchers discovered that poor sleep was strongly linked to worse pain, fatigue, anxiety, depression, and lower quality of life overall. Several factors—including pain intensity, mood problems, fibromyalgia, and autonomic nervous system dysfunction—were particularly associated with sleep difficulties.

Pain and SensitizationSleepAutonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

The etiologic relation between disequilibrium and orthostatic intolerance in patients with myalgic encephalomyelitis (chronic fatigue syndrome).

Miwa, Kunihisa, Inoue, Yukichi·Journal of cardiology·2018

This study looked at 44 ME/CFS patients to understand why they struggle to stay upright (orthostatic intolerance). Researchers found that balance problems—difficulty staying steady when standing with eyes closed—were common and seemed to make orthostatic intolerance worse. Patients with balance problems were more likely to have trouble completing a 10-minute standing test than those with only heart rate changes, suggesting balance issues may be just as important as blood pressure and heart rate problems in ME/CFS.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Cardiovascular characteristics of chronic fatigue syndrome.

Bozzini, Sara, Albergati, Andrea, Capelli, Enrica et al.·Biomedical reports·2018

This study looked at heart and blood pressure problems in people with ME/CFS. Researchers found that patients with ME/CFS tend to have lower blood pressure than expected, which may explain some common symptoms like dizziness, fatigue, and difficulty concentrating. Most other heart measurements were similar between people with and without ME/CFS.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredObservational

The effects of warm water immersion on blood pressure, heart rate and heart rate variability in people with chronic fatigue syndrome.

Parker, Romy, Higgins, Zeenath, Mlombile, Zandiswa N P et al.·The South African journal of physiotherapy·2018

This study looked at how warm water bathing affects heart function in people with ME/CFS compared to healthy people. Researchers found that people with ME/CFS had less stable heart rate patterns before entering warm water, but this improved during the water immersion. The heart rate stayed slightly elevated in the ME/CFS group even after leaving the water. Overall, warm water immersion appeared safe and may help with managing ME/CFS symptoms.

Autonomic Nervous System

E2 ModerateCohortPEM requiredCase-Control

Autonomic Nervous System Functioning Related to Nocturnal Sleep in Patients With Chronic Fatigue Syndrome Compared to Tired Controls.

Orjatsalo, Maija, Alakuijala, Anniina, Partinen, Markku·Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine·2018

This study examined how the nervous system controls heart rate and blood pressure during sleep in ME/CFS patients compared to people without the condition. Researchers found that ME/CFS patients showed unusual patterns during sleep: their sympathetic nervous system (the 'fight or flight' system) was more active than normal, while their parasympathetic nervous system (the 'rest and digest' system) was less active, especially during deep sleep. This abnormal nervous system activity during sleep may help explain why ME/CFS patients often wake up feeling unrefreshed.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Urodynamic characteristics might be variable in bladder pain syndrome/interstitial cystitis patients with different non-bladder co-morbid conditions.

Cheng, Wei-Ming, Fan, Yu-Hua, Lin, Alex T L·Journal of the Chinese Medical Association : JCMA·2018

This study looked at how other health conditions that often occur alongside bladder pain syndrome (interstitial cystitis) might affect bladder function. Researchers tested 111 patients with bladder pain and found that 78% also had at least one other condition, such as irritable bowel syndrome, fibromyalgia, or chronic fatigue syndrome. They discovered that patients with both bladder pain and irritable bowel syndrome had different bladder function patterns than those with bladder pain alone.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Negative Affectivity, Depression, and Resting Heart Rate Variability (HRV) as Possible Moderators of Endogenous Pain Modulation in Functional Somatic Syndromes.

Van Den Houte, Maaike, Van Oudenhove, Lukas, Van Diest, Ilse et al.·Frontiers in psychology·2018

This study looked at how the body's natural pain-blocking system works in people with fibromyalgia and chronic fatigue syndrome (CFS), and whether mood, depression, or heart rate variability might affect this system. Researchers compared 78 patients with these conditions to 33 healthy people using a test where they applied cold and electrical stimuli to see if pain would decrease. Unfortunately, the main pain-blocking effect the researchers expected to find did not appear in either group, so they could not draw clear conclusions about what affects pain modulation.

Pain and SensitizationAutonomic Nervous System

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Hemodynamics during the 10-minute NASA Lean Test: evidence of circulatory decompensation in a subset of ME/CFS patients.

Impairments in cognitive performance in chronic fatigue syndrome are common, not related to co-morbid depression but do associate with autonomic dysfunction.

Fatigue in Epstein-Barr virus infected adolescents and healthy controls: A prospective multifactorial association study.

A cluster analysis of serious adverse event reports after human papillomavirus (HPV) vaccination in Danish girls and young women, September 2009 to August 2017.

Long Term Follow up of Young People With Chronic Fatigue Syndrome Attending a Pediatric Outpatient Service.

Relationship Between Exercise-induced Oxidative Stress Changes and Parasympathetic Activity in Chronic Fatigue Syndrome: An Observational Study in Patients and Healthy Subjects.

Associations Between Autonomic and Orthostatic Self-report and Physician Ratings of Orthostatic Intolerance in Youth.

Orthostatic intolerance in chronic fatigue syndrome.

Autonomic dysfunction in myalgic encephalomyelitis and chronic fatigue syndrome: comparing self-report and objective measures.

Low Sensitivity of Abbreviated Tilt Table Testing for Diagnosing Postural Tachycardia Syndrome in Adults With ME/CFS.

Verification of exercise-induced transient postural tachycardia phenotype in Gulf War Illness.

Intracranial compliance is associated with symptoms of orthostatic intolerance in chronic fatigue syndrome.

Circadian rhythm abnormalities and autonomic dysfunction in patients with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis.

Poor self-reported sleep quality and health-related quality of life in patients with chronic fatigue syndrome/myalgic encephalomyelitis.

The etiologic relation between disequilibrium and orthostatic intolerance in patients with myalgic encephalomyelitis (chronic fatigue syndrome).

Cardiovascular characteristics of chronic fatigue syndrome.

The effects of warm water immersion on blood pressure, heart rate and heart rate variability in people with chronic fatigue syndrome.

Autonomic Nervous System Functioning Related to Nocturnal Sleep in Patients With Chronic Fatigue Syndrome Compared to Tired Controls.

Urodynamic characteristics might be variable in bladder pain syndrome/interstitial cystitis patients with different non-bladder co-morbid conditions.

Negative Affectivity, Depression, and Resting Heart Rate Variability (HRV) as Possible Moderators of Endogenous Pain Modulation in Functional Somatic Syndromes.

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