ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2781–2800 of 6,209 studies

E2 ModerateCohortPEM not requiredCase-Control

Functional characterization of muscle fibres from patients with chronic fatigue syndrome: case-control study.

Pietrangelo, T, Toniolo, L, Paoli, A et al.·International journal of immunopathology and pharmacology·2009

This study looked at muscle tissue from ME/CFS patients and compared it to healthy controls. Researchers found that ME/CFS patients had a shift in their muscle fiber types—more of the fast-twitch fibers (which tire easily) and fewer slow-twitch fibers (which are better for endurance). However, the individual muscle fibers themselves worked normally; the problem was the wrong mix of fiber types, which could explain why ME/CFS patients get tired so quickly.

E2 ModerateCohortPEM not requiredObservational

Lower ambulatory blood pressure in chronic fatigue syndrome.

Newton, Julia L, Sheth, Amish, Shin, Jane et al.·Psychosomatic medicine·2009

This study measured blood pressure patterns over 24 hours in people with ME/CFS, healthy volunteers, and people with a liver disease that also causes fatigue. The researchers found that ME/CFS patients had lower blood pressure than healthy people and their blood pressure did not drop as much during sleep as it normally should. Higher fatigue levels were linked to these abnormal blood pressure patterns.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Psychiatric comorbidity in persons with chronic fatigue syndrome identified from the Georgia population.

Nater, Urs M, Lin, Jin-Mann S, Maloney, Elizabeth M et al.·Psychosomatic medicine·2009

This study looked at how often people with ME/CFS also have psychiatric conditions like depression or anxiety. Researchers called random people in Georgia and invited those who were unwell to participate. They found that 57% of people with ME/CFS had at least one current psychiatric diagnosis, compared to 45% of people with similar but milder symptoms. Importantly, most people with ME/CFS who had these psychiatric conditions hadn't seen a mental health specialist in the past 6 months.

Diagnostics

E2 ModerateMechanismPEM not requiredMechanistic

RETRACTED: Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome.

Lombardi, Vincent C, Ruscetti, Francis W, Das Gupta, Jaydip et al.·Science (New York, N.Y.)·2009

This study, which has since been retracted, reported finding a virus called XMRV in blood cells from most ME/CFS patients tested, but rarely in healthy people. The researchers showed that this virus could be grown in the lab and transmitted between cells. However, subsequent studies by other scientists could not reproduce these findings, leading to the retraction of this paper.

Immune System

E2 ModerateCohortPEM not requiredLongitudinal

Health of US veterans of 1991 Gulf War: a follow-up survey in 10 years.

Kang, Han K, Li, Bo, Mahan, Clare M et al.·Journal of occupational and environmental medicine·2009

This study followed over 30,000 U.S. military veterans for 14 years after the 1991 Gulf War to track their health. Veterans who were deployed to the Gulf reported significantly more chronic fatigue, unexplained multi-symptom illness, PTSD, and other health problems compared to veterans who were not deployed. These health differences persisted over time, suggesting the Gulf deployment had lasting effects on veterans' wellbeing.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Unexplained chronic fatigue and interpersonal problems: a study in a primary care population.

Vandenbergen, Jan, Vanheule, Stijn, Desmet, Mattias et al.·International journal of psychiatry in medicine·2009

This study looked at whether people with ME/CFS experience more social withdrawal and interpersonal difficulties than people with other health conditions. Researchers found that ME/CFS patients reported much higher fatigue levels and were more likely to withdraw from social activities compared to people with minor illnesses. Interestingly, doctors and patients often disagreed about how motivated patients were, which may contribute to patients feeling misunderstood and isolated.

E2 ModerateBehavioralPEM not requiredCross-Sectional

[Relationship between chronic fatigue syndrome and type A behaviour].

Godás Sieso, Teresa, Gómez Gil, Esther, Salamero Baró, Manel et al.·Medicina clinica·2009

This study examined whether people with ME/CFS tend to have Type A personality traits—characteristics like urgency, competitiveness, and high-striving behavior. Researchers gave 82 ME/CFS patients a personality questionnaire and found their Type A scores were notably higher than healthy people and even higher than heart disease patients. The authors suggest that Type A personality may be connected to ME/CFS and should be considered when treating the condition.

E2 ModerateCohortPEM not requiredLongitudinal

Chronic fatigue syndrome after infectious mononucleosis in adolescents.

Katz, Ben Z, Shiraishi, Yukiko, Mears, Cynthia J et al.·Pediatrics·2009

This study followed 301 teenagers with infectious mononucleosis (mono) to see how many developed ME/CFS afterward. Researchers checked in at 6, 12, and 24 months and found that fewer teenagers had ME/CFS as time went on: 13% at 6 months, 7% at 12 months, and 4% at 24 months. All 13 teenagers still diagnosed with ME/CFS at 24 months were female, and they had reported more severe fatigue earlier in their illness.

E2 ModerateCohortPEM not requiredCross-Sectional

An investigation into the cognitive deficits associated with chronic fatigue syndrome.

Thomas, Marie, Smith, Andrew·The open neurology journal·2009

This study tested whether people with ME/CFS have real problems with thinking and memory, not just imagine they do. The researchers gave a large group of properly diagnosed ME/CFS patients a thorough set of cognitive tests and found clear evidence of cognitive difficulties. Importantly, these problems were not caused by depression or anxiety, suggesting they are a direct part of the illness.

Cognitive Impairment

E2 ModerateCohortPEM unclearCase-Control

Risk markers for both chronic fatigue and irritable bowel syndromes: a prospective case-control study in primary care.

Hamilton, W T, Gallagher, A M, Thomas, J M et al.·Psychological medicine·2009

This study looked at whether ME/CFS and irritable bowel syndrome (IBS) share common triggers or underlying causes. Researchers compared nearly 4,400 patients with fatigue syndromes to two control groups and found that infections—especially viral infections—appeared before ME/CFS developed, while stomach infections were more common before IBS. The findings suggest that while both conditions may have similar predisposing factors, the specific triggers that cause them to develop are different.

E2 ModerateCohortPEM not requiredCross-Sectional

An angiotensin-1 converting enzyme polymorphism is associated with allostatic load mediated by C-reactive protein, interleukin-6 and cortisol.

Smith, Alicia K, Maloney, Elizabeth M, Falkenberg, Virginia R et al.·Psychoneuroendocrinology·2009

This study looked at whether a specific genetic variation in a gene called ACE affects how people's bodies respond to stress and illness. Researchers measured multiple stress-related markers (inflammation, immune system activity, and cortisol levels) in people with and without ME/CFS. They found that people carrying a particular version of the ACE gene tended to have higher stress responses and more inflammation, suggesting genes may play a role in how severely someone's body reacts to stress.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Replication of an empirical approach to delineate the heterogeneity of chronic unexplained fatigue.

Aslakson, Eric, Vollmer-Conna, Uté, Reeves, William C et al.·Population health metrics·2009

This study looked at nearly 400 women from different parts of Georgia to understand why chronic fatigue affects people so differently. Instead of treating all chronic fatigue as one disease, researchers found that people fall into five distinct groups with different symptom patterns—some with sleep and mood problems, some with weight and metabolic issues, and some without significant fatigue at all. The findings suggest that chronic fatigue is not one-size-fits-all, and doctors may need personalized approaches for different patient groups.

Sleep

E2 ModerateBehavioralPEM not requiredCross-Sectional

Illness behaviors in patients with unexplained chronic fatigue are associated with significant other responses.

Romano, Joan M, Jensen, Mark P, Schmaling, Karen B et al.·Journal of behavioral medicine·2009

This study looked at how the responses of family members and close partners affect people with chronic fatigue. Researchers found that when significant others were supportive or 'solicitous' (caring and attentive), patients tended to show more illness-related behaviors. Interestingly, when significant others responded negatively, patients reported higher levels of depression. The findings suggest that social interactions and family dynamics may play a role in how chronic fatigue affects daily functioning.

E2 ModerateCohortPEM not requiredCross-Sectional

A comparison of dysautonomias comorbid with cyclic vomiting syndrome and with migraine.

Chelimsky, Gisela, Madan, Shruti, Alshekhlee, Amer et al.·Gastroenterology research and practice·2009

This study compared people with cyclic vomiting syndrome (CVS) to people with migraine headaches to see if they have the same associated conditions. Researchers looked at 21 CVS patients, 46 migraine patients, and 36 healthy controls, testing for 12 different conditions including orthostatic intolerance (feeling dizzy when standing), fibromyalgia, and chronic fatigue. While CVS and migraine shared many of the same comorbidities, CVS patients had significantly more cases of complex regional pain syndrome, suggesting these conditions may not be as similar as previously thought.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Illness perceptions in patients with fibromyalgia.

van Ittersum, M W, van Wilgen, C P, Hilberdink, W K H A et al.·Patient education and counseling·2009

This study looked at how people with fibromyalgia understand and perceive their illness by having 196 patients complete a questionnaire. The researchers found that fibromyalgia patients often feel confused about their condition, believe it will last a long time, and worry it will significantly impact their daily life. The questionnaire tool was found to be reliable for measuring these beliefs in Dutch-speaking fibromyalgia patients.

E2 ModerateCohortPEM not requiredObservational

Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function.

Hurwitz, Barry E, Coryell, Virginia T, Parker, Meela et al.·Clinical science (London, England : 1979)·2009

This study found that people with severe ME/CFS have smaller hearts and significantly less blood volume compared to healthy controls. The reduced heart size appears to be caused by having less blood circulating in their bodies, not by weak heart muscle. The researchers suggest this blood volume deficit—a condition where the body has less circulating blood than normal—may be an important factor in ME/CFS symptoms.

E2 ModerateCohortPEM not requiredCross-Sectional

Electroencephalographic correlates of Chronic Fatigue Syndrome.

Decker, Michael J, Tabassum, Humyra, Lin, Jin-Mann S et al.·Behavioral and brain functions : BBF·2009

This study looked at brain wave patterns during sleep in people with ME/CFS compared to healthy controls using a sleep study test. Researchers found that people with ME/CFS had abnormal brain wave activity during different sleep stages, particularly weaker delta waves during deep sleep and weaker alpha waves during REM sleep. These findings suggest that the problem in ME/CFS may not be the structure of sleep itself, but rather how the brain regulates and maintains restorative sleep.

Sleep

E2 ModerateMechanismPEM not requiredMechanistic

Transcription profile analysis of vastus lateralis muscle from patients with chronic fatigue syndrome.

Pietrangelo, T, Mancinelli, R, Toniolo, L et al.·International journal of immunopathology and pharmacology·2009

Researchers examined muscle tissue from ME/CFS patients and found abnormalities in how genes are expressed—essentially, certain genetic instructions were turned up or down compared to healthy people. The biggest changes involved genes related to energy production in cells, muscle structure, and communication between nerves and muscles. These findings suggest that problems at the cellular level may explain why ME/CFS patients experience muscle weakness and fatigue.

Energy Metabolism

E2 ModerateBehavioralPEM unclearObservational

The impact of energy modulation on physical functioning and fatigue severity among patients with ME/CFS.

Jason, Leonard, Benton, Mary, Torres-Harding, Susan et al.·Patient education and counseling·2009

This study looked at whether ME/CFS patients could improve by carefully managing their daily energy use to match their available energy. Researchers tracked patients who tried to stay within their "energy envelope"—basically not spending more energy than they have. Patients who were able to do this successfully reported feeling less tired and being more physically able to do daily activities.

E2 ModerateCohortPEM not requiredCross-Sectional

Barriers to healthcare utilization in fatiguing illness: a population-based study in Georgia.

Lin, Jin-Mann S, Brimmer, Dana J, Boneva, Roumiana S et al.·BMC health services research·2009

This study looked at why people with ME/CFS and other fatiguing illnesses skip or delay needed medical care. Researchers surveyed 780 people, including 112 with CFS, and found that 55% of those with CFS faced barriers to getting healthcare. The main barriers fell into three categories: trouble accessing care (like travel or scheduling), healthcare providers' attitudes and knowledge gaps, and problems with how the healthcare system itself works.

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Functional characterization of muscle fibres from patients with chronic fatigue syndrome: case-control study.

Lower ambulatory blood pressure in chronic fatigue syndrome.

Psychiatric comorbidity in persons with chronic fatigue syndrome identified from the Georgia population.

RETRACTED: Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome.

Health of US veterans of 1991 Gulf War: a follow-up survey in 10 years.

Unexplained chronic fatigue and interpersonal problems: a study in a primary care population.

[Relationship between chronic fatigue syndrome and type A behaviour].

Chronic fatigue syndrome after infectious mononucleosis in adolescents.

An investigation into the cognitive deficits associated with chronic fatigue syndrome.

Risk markers for both chronic fatigue and irritable bowel syndromes: a prospective case-control study in primary care.

An angiotensin-1 converting enzyme polymorphism is associated with allostatic load mediated by C-reactive protein, interleukin-6 and cortisol.

Replication of an empirical approach to delineate the heterogeneity of chronic unexplained fatigue.

Illness behaviors in patients with unexplained chronic fatigue are associated with significant other responses.

A comparison of dysautonomias comorbid with cyclic vomiting syndrome and with migraine.

Illness perceptions in patients with fibromyalgia.

Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function.

Electroencephalographic correlates of Chronic Fatigue Syndrome.

Transcription profile analysis of vastus lateralis muscle from patients with chronic fatigue syndrome.

The impact of energy modulation on physical functioning and fatigue severity among patients with ME/CFS.

Barriers to healthcare utilization in fatiguing illness: a population-based study in Georgia.

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