ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2785 studies

2021–2040 of 2,785 studies

E2 ModerateCohortPEM not requiredCross-Sectional

[Cognitive function and psychological characteristics of patients with chronic fatigue syndrome].

Li, Yong-jie, Gao, Xu-guang, Wang, De-Xin et al.·Zhonghua yi xue za zhi·2005

This study looked at how ME/CFS affects thinking and memory in 91 Chinese patients compared to 30 healthy people. Researchers found that 90% of ME/CFS patients had problems with memory and attention, and most also experienced depression, anxiety, and obsessive thoughts. The results show that ME/CFS causes real cognitive problems that are different from those seen in psychiatric illnesses alone.

Cognitive Impairment

E2 ModerateCohortPEM unclearCross-Sectional

Long-term medical conditions and major depression: strength of association for specific conditions in the general population.

Patten, Scott B, Beck, Cynthia A, Kassam, Aliya et al.·Canadian journal of psychiatry. Revue canadienne de psychiatrie·2005

This study looked at whether people with long-term medical conditions are more likely to experience depression. Researchers surveyed over 115,000 Canadians and found that people with chronic fatigue syndrome (ME/CFS) had the strongest link to depression—more than 7 times higher than those without the condition. Fibromyalgia also showed a strong connection to depression, while conditions like high blood pressure and diabetes had weaker connections.

E2 ModerateCohortPEM not requiredCross-Sectional

Prevalence and correlates of nonrestorative sleep complaints.

Ohayon, Maurice M·Archives of internal medicine·2005

This study surveyed over 25,000 people across seven European countries to understand how common nonrestorative sleep (feeling unrefreshed after sleep) is and what factors are linked to it. Researchers found that about 1 in 10 people experience nonrestorative sleep, with women and younger adults affected more often. People with this symptom reported worse daytime tiredness and mental fatigue compared to those with other sleep problems.

E2 ModerateCohortPEM not requiredCross-Sectional

Is chronic fatigue syndrome a connective tissue disorder? A cross-sectional study in adolescents.

van de Putte, E M, Uiterwaal, C S P M, Bots, M L et al.·Pediatrics·2005

Researchers investigated whether ME/CFS is related to loose or stretchy connective tissue (the material that holds joints, skin, and blood vessels together). They compared 32 adolescents with ME/CFS to 167 healthy teenagers and measured joint flexibility, blood pressure, skin stretchiness, and blood vessel stiffness. While they found some differences—including lower blood pressure and stretchier skin in the ME/CFS group—they did not find the joint hypermobility that would be expected if ME/CFS were a connective tissue disorder.

E2 ModerateCohortPEM not requiredCross-Sectional

Plasma and urinary carnitine and acylcarnitines in chronic fatigue syndrome.

Jones, Mark G, Goodwin, C Stewart, Amjad, Saira et al.·Clinica chimica acta; international journal of clinical chemistry·2005

Researchers tested whether people with ME/CFS have low levels of carnitine, a substance that helps muscles produce energy. They compared blood and urine samples from 31 ME/CFS patients with samples from healthy people and patients with other conditions. The study found no significant differences in carnitine levels between the groups, suggesting that low carnitine is not responsible for the fatigue experienced by ME/CFS patients.

Energy Metabolism

E2 ModerateBehavioralPEM not requiredCross-Sectional

The relationships among coping styles and fatigue in an ethnically diverse sample.

Njoku, Mary Gloria C, Jason, Leonard A, Torres-Harding, Susan R·Ethnicity & health·2005

This study looked at how people from different ethnic backgrounds (African Americans, Latinos, and European Americans) cope with ME/CFS and chronic fatigue. Researchers asked patients about their coping strategies—like turning to religion, staying active, accepting their illness, or focusing on their symptoms. The study found that different ethnic groups tend to use different coping strategies, and some approaches (like denial) seemed to be less helpful across all groups.

E2 ModerateCohortPEM not requiredCase-Control

GB virus-C--a virus without a disease: we cannot give it chronic fatigue syndrome.

Jones, James F, Kulkarni, Prasad S, Butera, Salvatore T et al.·BMC infectious diseases·2005

This study investigated whether a virus called GB virus-C (GBV-C) might be a cause of ME/CFS. Researchers tested blood samples from CFS patients and healthy controls for signs of current or past GBV-C infection. They found no significant difference between the two groups, leading them to conclude that GBV-C is unlikely to be responsible for causing ME/CFS.

E2 ModerateCohortPEM unclearLongitudinal

Time course of exercise induced alterations in daily activity in chronic fatigue syndrome.

Black, Christopher D, McCully, Kevin K·Dynamic medicine : DM·2005

This study tracked how much physical activity people with ME/CFS could do while following a walking program. Participants wore activity monitors for 4 weeks. They were able to meet their daily walking goals for the first 1-2 weeks, but then their activity levels dropped significantly and symptoms got worse, suggesting they had hit a limit their bodies could not sustain.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCase-Control

Association of chronic fatigue syndrome with human leucocyte antigen class II alleles.

Smith, J, Fritz, E L, Kerr, J R et al.·Journal of clinical pathology·2005

This study looked at whether certain genetic markers related to the immune system (called HLA types) are more common in people with ME/CFS than in healthy people. Researchers compared the genetic profiles of 49 ME/CFS patients with 102 healthy controls from the same region of England. They found that one particular genetic marker (HLA-DQA1*01) was significantly more common in ME/CFS patients, suggesting genes may play a role in who develops this illness.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Gulf War veterans' health: medical evaluation of a U.S. cohort.

Eisen, Seth A, Kang, Han K, Murphy, Frances M et al.·Annals of internal medicine·2005

This study looked at over 2,000 U.S. veterans from the 1991 Gulf War, comparing those who were deployed to the Persian Gulf with those who were not. Researchers found that deployed veterans had higher rates of chronic fatigue syndrome, fibromyalgia, skin problems, and stomach issues 10 years after the war. Overall physical health scores were similar between the two groups, but the increased risk of these specific conditions in deployed veterans suggests Gulf War deployment may have lasting health effects.

E2 ModerateCohortPEM not requiredCross-Sectional

The prevalence of self-reported chronic fatigue in a U.S. twin registry.

Furberg, Helena, Olarte, Megan, Afari, Niloo et al.·Journal of psychosomatic research·2005

This study looked at how common fatigue-related illnesses are among twins in the United States and found that fatigue symptoms are quite common, affecting over one-third of people at some point in their lives. Women were 2-3 times more likely to report fatigue than men, and women typically experienced it at younger ages. People with chronic fatigue had significantly worse quality of life and more additional symptoms than those without fatigue.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Reliability of physiological, psychological, and cognitive variables in chronic fatigue syndrome.

Wallman, Karen E, Morton, Alan R, Goodman, Carmel et al.·Research in sports medicine (Print)·2005

Researchers tested whether measurements of fatigue, mood, thinking ability, and physical performance in ME/CFS patients were reliable when checked weekly over four weeks. Most measurements were reliable and consistent, but fatigue ratings—both mental and physical—varied too much week-to-week to be fully trusted. Interestingly, how well people performed during exercise didn't match up well with their reported depression or mood, suggesting the problem may be in how the brain processes fatigue rather than actual muscle weakness.

Pain and Sensitization

E2 ModerateCohortPEM unclearCase-Control

Chronic fatigue syndrome--a clinically empirical approach to its definition and study.

Reeves, William C, Wagner, Dieter, Nisenbaum, Rosane et al.·BMC medicine·2005

This study tested two different ways of diagnosing ME/CFS to see which one worked better. Researchers in Kansas recruited 227 people—some with ME/CFS, some with unexplained fatigue that didn't meet ME/CFS criteria, some depressed, and some healthy—and admitted them to a hospital for two days of testing. They found that a new method for diagnosing ME/CFS (based on measuring fatigue severity, disability, and symptoms) worked much better at identifying truly ill people than the old method.

Diagnostics

E2 ModerateCohortPEM unclearCross-Sectional

Ambulatory monitoring of physical activity and symptoms in fibromyalgia and chronic fatigue syndrome.

Kop, Willem J, Lyden, Angela, Berlin, Ali A et al.·Arthritis and rheumatism·2005

This study used activity trackers to measure how much people with ME/CFS and fibromyalgia move during daily life, and whether their pain and fatigue change based on activity levels. The researchers found that patients with these conditions did less intense activity and experienced more pain and fatigue when they were less active, but interestingly, having pain or fatigue seemed to cause them to reduce activity rather than the other way around.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic fatigue syndrome: exercise performance related to immune dysfunction.

Nijs, Jo, Meeus, Mira, McGregor, Neil R et al.·Medicine and science in sports and exercise·2005

This study looked at whether problems with the immune system might explain why people with ME/CFS feel exhausted after exercise and cannot exercise as much as healthy people. Researchers tested 16 ME/CFS patients' immune cells and had them exercise on a stationary bike while measuring their oxygen use and heart rate. They found that two specific immune markers—elastase and protein kinase R—were linked to reduced exercise capacity, suggesting immune dysfunction may play a role in abnormal exercise responses.

Immune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome of childhood. Comparative study with emotional disorders.

Garralda, M Elena, Rangel, Luiza·European child & adolescent psychiatry·2005

This study compared children diagnosed with ME/CFS to children with emotional disorders like anxiety and depression to see how these conditions differ. While both groups of children experienced some similar emotional challenges, children with ME/CFS reported more severe tiredness and physical symptoms, and were more likely to have had infections or medical problems before getting sick. The results show that ME/CFS and emotional disorders can look similar in some ways but have important differences.

Diagnostics

E2 ModerateCohortPEM not requiredObservational

Increased daily physical activity and fatigue symptoms in chronic fatigue syndrome.

Black, Christopher D, O'connor, Patrick J, McCully, Kevin K·Dynamic medicine : DM·2005

This small study asked 6 people with ME/CFS to increase their daily walking by about 30% for 4 weeks and tracked how they felt. Unlike some previous research suggesting exercise helps, these patients reported that their muscle pain and mood actually got worse with more activity, even though they were able to increase their activity level. The researchers suggest that people with ME/CFS may have a daily limit to how much activity they can do before symptoms worsen.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCase-Control

Normal opioid tone and hypothalamic-pituitary-adrenal axis function in chronic fatigue syndrome despite marked functional impairment.

Inder, Warrick J, Prickett, Timothy C R, Mulder, Roger T·Clinical endocrinology·2005

This study tested whether ME/CFS is caused by low levels of pain-relieving chemicals (opioids) in the brain or problems with the stress hormone system. Researchers measured hormone levels and responses in 12 ME/CFS patients and 11 healthy people, and found no differences between the groups, suggesting these hormonal systems are working normally in ME/CFS despite severe fatigue and physical limitations.

Endocrine Disruption

E2 ModerateCohortPEM not requiredObservational

JP-8 jet fuel exposure and divided attention test performance in 1991 Gulf War veterans.

Bell, Iris R, Brooks, Audrey J, Baldwin, Carol M et al.·Aviation, space, and environmental medicine·2005

This study examined how exposure to low levels of jet fuel affected thinking and attention in Gulf War veterans who were chronically ill. Researchers tested veterans' reaction times on a computer task before and after brief exposures to either jet fuel fumes or clean air, done three times over three weeks. Veterans who were ill and had chemical sensitivities showed faster reaction times after jet fuel exposure, which the researchers suggest might indicate changes in brain chemistry rather than improved thinking.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Decreased dehydroepiandrosterone sulfate but normal insulin-like growth factor in chronic fatigue syndrome (CFS): relevance for the inflammatory response in CFS.

Maes, Michael, Mihaylova, Ivana, De Ruyter, Marcel·Neuro endocrinology letters·2005

This study compared hormone levels in people with ME/CFS to healthy controls. Researchers found that ME/CFS patients had significantly lower levels of DHEAS (a hormone made by the adrenal glands), but normal levels of another hormone called IGF1. The low DHEAS was closely linked to markers of immune system activation and inflammation, suggesting this hormone imbalance may contribute to ME/CFS symptoms.

Immune System

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[Cognitive function and psychological characteristics of patients with chronic fatigue syndrome].

Long-term medical conditions and major depression: strength of association for specific conditions in the general population.

Prevalence and correlates of nonrestorative sleep complaints.

Is chronic fatigue syndrome a connective tissue disorder? A cross-sectional study in adolescents.

Plasma and urinary carnitine and acylcarnitines in chronic fatigue syndrome.

The relationships among coping styles and fatigue in an ethnically diverse sample.

GB virus-C--a virus without a disease: we cannot give it chronic fatigue syndrome.

Time course of exercise induced alterations in daily activity in chronic fatigue syndrome.

Association of chronic fatigue syndrome with human leucocyte antigen class II alleles.

Gulf War veterans' health: medical evaluation of a U.S. cohort.

The prevalence of self-reported chronic fatigue in a U.S. twin registry.

Reliability of physiological, psychological, and cognitive variables in chronic fatigue syndrome.

Chronic fatigue syndrome--a clinically empirical approach to its definition and study.

Ambulatory monitoring of physical activity and symptoms in fibromyalgia and chronic fatigue syndrome.

Chronic fatigue syndrome: exercise performance related to immune dysfunction.

Chronic fatigue syndrome of childhood. Comparative study with emotional disorders.

Increased daily physical activity and fatigue symptoms in chronic fatigue syndrome.

Normal opioid tone and hypothalamic-pituitary-adrenal axis function in chronic fatigue syndrome despite marked functional impairment.

JP-8 jet fuel exposure and divided attention test performance in 1991 Gulf War veterans.

Decreased dehydroepiandrosterone sulfate but normal insulin-like growth factor in chronic fatigue syndrome (CFS): relevance for the inflammatory response in CFS.

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