ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2881–2900 of 6,209 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Seroprevalence of antibodies to Coxiella burnetii among employees of the Veterinary University in Kosice, eastern Slovakia.

Dorko, Erik, Kalinova, Zuzana, Weissova, Tatiana et al.·Annals of agricultural and environmental medicine : AAEM·2008

This study tested veterinary university employees in Slovakia for past or present infection with a bacteria called Coxiella burnetii, which causes Q fever—a disease spread mainly through contact with infected animals or their fluids. Researchers found that more than one-third of the employees had antibodies (immune markers) suggesting exposure to this bacteria, and some employees reported having chronic fatigue syndrome, fever of unknown origin, and other unexplained health problems.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Disability associated with comorbid anxiety disorders in women with chronic physical illness in Ontario, Canada.

Gadalla, Tahany M·Women & health·2008

This study looked at data from over 40,000 Canadian adults to understand how anxiety disorders affect people with chronic illnesses, particularly women. The researchers found that women with chronic physical illnesses—including ME/CFS, fibromyalgia, and digestive problems—are much more likely to also experience anxiety disorders. When anxiety and physical illness occur together, people report more disability in daily activities and higher rates of suicidal thoughts.

E2 ModerateBehavioralPEM unclearCross-Sectional

Symptoms, impairment and illness intrusiveness--their relationship with depression in women with CFS/ME.

Dancey, Christine P, Friend, Julie·Psychology & health·2008

This study looked at how ME/CFS symptoms and daily limitations affect depression in women with the illness. The researchers found that ME/CFS is particularly intrusive—it disrupts many areas of life more than other chronic illnesses do. How much the illness disrupts daily life turned out to be the strongest predictor of whether someone develops depression, more so than the symptoms or impairments alone.

E2 ModerateCohortPEM unclearCross-Sectional

The Energy Envelope Theory and myalgic encephalomyelitis/chronic fatigue syndrome.

Jason, Leonard, Muldowney, Kathleen, Torres-Harding, Susan·AAOHN journal : official journal of the American Association of Occupational Health Nurses·2008

This study tested the Energy Envelope Theory, which suggests that ME/CFS symptoms get worse when people spend more energy than they have available. Researchers asked people with ME/CFS to track their daily energy use compared to their available energy, and found that those who exceeded their energy budget experienced more severe fatigue, pain, depression, anxiety, and reduced quality of life. The findings support the idea that staying within your energy limits may help manage ME/CFS symptoms.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Electrocardiographic QT interval and cardiovascular reactivity in fibromyalgia differ from chronic fatigue syndrome.

Naschitz, Jochanan E, Slobodin, Gleb, Sharif, Dauod et al.·European journal of internal medicine·2008

This study found that ME/CFS and fibromyalgia, two conditions that seem similar on the surface, actually show different patterns on heart tests. People with ME/CFS had shorter QT intervals on their electrocardiogram (a measure of heart electrical activity) and had more dramatic blood pressure and heart rate changes during a tilting test compared to people with fibromyalgia. These differences suggest the two conditions may be distinct disorders rather than variants of the same illness.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Memory for fatigue in chronic fatigue syndrome: relationships to fatigue variability, catastrophizing, and negative affect.

Sohl, Stephanie J, Friedberg, Fred·Behavioral medicine (Washington, D.C.)·2008

This study explored how ME/CFS patients remember their fatigue compared to what they actually experience day-to-day. Over 3 weeks, 53 patients recorded their fatigue levels as they happened, then recalled how fatigued they had been the previous week. The research found that people who had more variable fatigue, as well as those struggling with worry, depression, or anxiety, tended to remember their fatigue differently than they actually experienced it.

E2 ModerateCohortPEM not requiredCross-Sectional

Validation of the energy index point score to serially measure the degree of disability in patients with chronic fatigue syndrome.

Lerner, A Martin, Beqaj, Safedin H, Fitzgerald, James T·In vivo (Athens, Greece)·2008

Researchers tested a simple scoring system called the Energy Index (EI) to measure fatigue severity in ME/CFS patients. They compared it to another well-known fatigue measurement tool (the Fatigue Severity Score) in 56 patients and found the two methods produced similar results. This suggests the Energy Index is a reliable way for doctors and patients to track how severe fatigue is and whether treatments are helping.

E2 ModerateCohortPEM not requiredCross-Sectional

Prevalence of chronic fatigue syndrome in metropolitan, urban, and rural Georgia.

Reeves, William C, Jones, James F, Maloney, Elizabeth et al.·Population health metrics·2007

This study surveyed over 5,600 people in Georgia to find out how many have ME/CFS. Researchers found that about 2.5% of adults aged 18-59 have the condition, which is higher than estimates from other parts of the United States. Interestingly, the disease affected men and women very differently depending on whether they lived in cities or rural areas.

E2 ModerateCohortPEM not requiredCross-Sectional

[Estimation of fatigue state in patient with CFS using actigraph and R-R interval power spectrum analysis].

Tajima, Seiki, Kuratsune, Hirohiko, Yamaguti, Kouzi et al.·Nihon rinsho. Japanese journal of clinical medicine·2007

This study measured activity levels and sleep patterns in people with ME/CFS using wearable devices and heart rate analysis. Researchers found that ME/CFS patients had lower activity during waking hours, slept longer, experienced more frequent sleep disruptions, and showed abnormal nervous system activity during sleep compared to healthy people.

SleepAutonomic Nervous System

E2 ModerateCohortPEM not requiredObservational

Defining the occurrence and influence of alpha-delta sleep in chronic fatigue syndrome.

Van Hoof, Elke, De Becker, Pascale, Lapp, Charles et al.·The American journal of the medical sciences·2007

This study looked at sleep patterns in 48 ME/CFS patients using overnight sleep recordings. Researchers found that patients had difficulty falling asleep, spent less time in deep restorative sleep, and showed an unusual pattern of brain waves (alpha-delta intrusion) during sleep. Interestingly, this abnormal sleep pattern was linked to anxiety rather than to immune system changes.

Immune System

E2 ModerateCohortPEM not requiredObservational

Actuarial analysis of private payer administrative claims data for women with endometriosis.

Mirkin, David, Murphy-Barron, Carrieann, Iwasaki, Kosuke·Journal of managed care pharmacy : JMCP·2007

This study looked at insurance claims from nearly 4 million people to understand how common endometriosis is and how much it costs to treat. Researchers found that women with endometriosis spend significantly more on medical care than other women, have frequent hospital stays and surgeries, and often have other health conditions at the same time—including chronic fatigue syndrome. The study shows endometriosis is a serious, expensive condition that affects many aspects of a woman's health.

E2 ModerateCohortPEM not requiredCross-Sectional

Usefulness of an abnormal cardiovascular response during low-grade head-up tilt-test for discriminating adolescents with chronic fatigue from healthy controls.

Wyller, Vegard Bruun, Due, Reidar, Saul, J Philip et al.·The American journal of cardiology·2007

This study tested how the hearts of adolescents with ME/CFS respond to mild physical stress (tilting the body slightly upright for 15 minutes) compared to healthy teenagers. Researchers found that young people with ME/CFS had abnormal heart and blood vessel responses during this test—their hearts beat faster, their blood pressure increased more, and their stroke volume (amount of blood pumped per heartbeat) decreased more than in healthy controls. These differences suggest that ME/CFS involves problems with how the body regulates blood flow and heart function during even mild stress.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredObservational

Not in the mind of neurasthenic lazybones but in the cell nucleus: patients with chronic fatigue syndrome have increased production of nuclear factor kappa beta.

Maes, Michael, Mihaylova, Ivana, Bosmans, Eugene·Neuro endocrinology letters·2007

This study found that people with ME/CFS have higher levels of a molecule called NF-kappa-beta in their white blood cells, both at rest and when stimulated by immune signals. This molecule controls inflammation and stress responses in cells. The higher the NF-kappa-beta levels, the more severe patients' symptoms—including fatigue, muscle pain, and feeling sick—were reported to be.

Immune System

E2 ModerateCohortPEM not requiredCase-Control

Low-resolution electromagnetic brain tomography (LORETA) of monozygotic twins discordant for chronic fatigue syndrome.

Sherlin, Leslie, Budzynski, Thomas, Kogan Budzynski, Helen et al.·NeuroImage·2007

Researchers used a special brain scanning technique called LORETA to measure electrical activity in the brains of identical twins—one with ME/CFS and one without. They found that twins with ME/CFS had different patterns of brain activity in specific regions, particularly in areas related to mood, energy management, and the nervous system's stress response. This suggests that ME/CFS may involve measurable differences in how certain parts of the brain function.

E2 ModerateCohortPEM unclearCase-Control

Temporomandibular disorder is associated with a serotonin transporter gene polymorphism in the Japanese population.

Ojima, Kiyomi, Watanabe, Nagaoki, Narita, Naoko et al.·BioPsychoSocial medicine·2007

This study looked at a specific genetic variation in the serotonin transporter gene in people with temporomandibular disorder (TMD)—a condition affecting the jaw joint. Researchers compared the genes of 36 patients with TMD to healthy controls and found that people with TMD were more likely to carry certain genetic variants related to serotonin, a chemical messenger in the brain. Since serotonin problems have been linked to chronic fatigue syndrome and similar conditions, this finding suggests genetics may play a role in TMD development.

E2 ModerateCohortPEM unclearObservational

A real-time assessment of the effect of exercise in chronic fatigue syndrome.

Yoshiuchi, Kazuhiro, Cook, Dane B, Ohashi, Kyoko et al.·Physiology & behavior·2007

This study looked at what happens to people with ME/CFS after they exercise, tracking their symptoms in real-time using a watch-like computer for a week before and two weeks after exercise. The main finding was that physical symptoms like pain and fatigue got worse in ME/CFS patients, but this didn't happen right away—it took about five days to appear. Interestingly, mental symptoms and thinking abilities didn't show the same delayed worsening pattern that physical symptoms did.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCase-Control

Higher heart rate and reduced heart rate variability persist during sleep in chronic fatigue syndrome: a population-based study.

Boneva, Roumiana S, Decker, Michael J, Maloney, Elizabeth M et al.·Autonomic neuroscience : basic & clinical·2007

This study found that people with ME/CFS have a faster heart rate and less heart rate variability (natural changes in heartbeat speed) during sleep compared to healthy people. These differences suggest that the nervous system in ME/CFS patients stays more activated even during sleep, which may be related to chemical imbalances in the body.

SleepAutonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Health status and health care utilization of multiple sclerosis in Canada.

Pohar, Sheri L, Jones, C Allyson, Warren, Sharon et al.·The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques·2007

This Canadian study compared people living with multiple sclerosis (MS) to people without MS to understand how the disease affects their daily lives and health care needs. People with MS reported much worse overall health, were far more likely to experience fatigue and urinary problems, and had greater health care utilization. The study found that MS significantly burdens patients' quality of life and that their health care needs were often not being met.

E2 ModerateCohortPEM not requiredCase-Control

Cold pressor pain sensitivity in monozygotic twins discordant for chronic fatigue syndrome.

Ullrich, Philip M, Afari, Niloofar, Jacobsen, Clemma et al.·Pain medicine (Malden, Mass.)·2007

This study compared identical twins where one had ME/CFS and one did not to understand pain sensitivity. Researchers tested how twins responded to cold pain and found that while people with ME/CFS reported significantly higher levels of pain and fatigue during the test, their actual physical pain thresholds were not substantially different from their unaffected twins. This suggests that the pain experience in ME/CFS may be more about how the brain perceives and processes pain rather than a difference in the body's basic pain detection system.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCross-Sectional

Exercise testing in children and adolescents with chronic fatigue syndrome.

Takken, T, Henneken, T, van de Putte, E et al.·International journal of sports medicine·2007

This study tested how well 20 young people with ME/CFS could exercise on a stationary bike and measured their oxygen use. The researchers found that most of these young people had similar exercise capacity to healthy peers their age, though a smaller group showed reduced fitness. The amount of fatigue they experienced was related to how active they were in daily life.

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Seroprevalence of antibodies to Coxiella burnetii among employees of the Veterinary University in Kosice, eastern Slovakia.

Disability associated with comorbid anxiety disorders in women with chronic physical illness in Ontario, Canada.

Symptoms, impairment and illness intrusiveness--their relationship with depression in women with CFS/ME.

The Energy Envelope Theory and myalgic encephalomyelitis/chronic fatigue syndrome.

Electrocardiographic QT interval and cardiovascular reactivity in fibromyalgia differ from chronic fatigue syndrome.

Memory for fatigue in chronic fatigue syndrome: relationships to fatigue variability, catastrophizing, and negative affect.

Validation of the energy index point score to serially measure the degree of disability in patients with chronic fatigue syndrome.

Prevalence of chronic fatigue syndrome in metropolitan, urban, and rural Georgia.

[Estimation of fatigue state in patient with CFS using actigraph and R-R interval power spectrum analysis].

Defining the occurrence and influence of alpha-delta sleep in chronic fatigue syndrome.

Actuarial analysis of private payer administrative claims data for women with endometriosis.

Usefulness of an abnormal cardiovascular response during low-grade head-up tilt-test for discriminating adolescents with chronic fatigue from healthy controls.

Not in the mind of neurasthenic lazybones but in the cell nucleus: patients with chronic fatigue syndrome have increased production of nuclear factor kappa beta.

Low-resolution electromagnetic brain tomography (LORETA) of monozygotic twins discordant for chronic fatigue syndrome.

Temporomandibular disorder is associated with a serotonin transporter gene polymorphism in the Japanese population.

A real-time assessment of the effect of exercise in chronic fatigue syndrome.

Higher heart rate and reduced heart rate variability persist during sleep in chronic fatigue syndrome: a population-based study.

Health status and health care utilization of multiple sclerosis in Canada.

Cold pressor pain sensitivity in monozygotic twins discordant for chronic fatigue syndrome.

Exercise testing in children and adolescents with chronic fatigue syndrome.

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