Evidence browser

E2 ModerateCohortPEM unclearCase-Control

No evidence of cross-species transmission of mouse retroviruses to animal workers exposed to mice.

Brooks, James, Lycett-Lambert, Karly, Caminiti, Kyna et al.·Transfusion·2012

Researchers tested 43 people who work closely with mice to see if they had been infected with mouse viruses (XMRV and MLV) that some scientists had previously linked to ME/CFS. Using blood tests and genetic analysis, they found no evidence that these viruses had jumped from mice to humans, even among workers with high exposure.

IgM-mediated autoimmune responses directed against anchorage epitopes are greater in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) than in major depression.

Maes, Michael, Mihaylova, Ivana, Kubera, Marta et al.·Metabolic brain disease·2012

This study examined immune system markers in people with ME/CFS, depression, and healthy controls. Researchers found that people with ME/CFS had higher levels of specific immune antibodies (IgM) attacking certain body molecules compared to people with depression. These antibodies were especially high against fatty acid anchors and oxidatively damaged proteins, suggesting ME/CFS may involve distinct immune processes that differ from depression.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Factor analysis of the Beck Depression Inventory-II with patients with chronic fatigue syndrome.

Brown, Molly, Kaplan, Carly, Jason, Leonard·Journal of health psychology·2012

This study looked at how well a depression screening tool (the Beck Depression Inventory-II) works for people with ME/CFS. The researchers found that the tool picks up on physical and emotional symptoms separately, and that people with ME/CFS tend to score high on the physical symptom questions because many overlap with ME/CFS symptoms like fatigue. A simpler version of the tool designed for primary care settings worked better for this group.

E2 ModerateCohortPEM not requiredLongitudinal

Orthostatic tolerance testing in a prospective cohort of adolescents with chronic fatigue syndrome and recovered controls following infectious mononucleosis.

Katz, Ben Z, Stewart, Julian M, Shiraishi, Yukiko et al.·Clinical pediatrics·2012

This study looked at whether teenagers with ME/CFS have trouble standing up for long periods (a condition called orthostatic intolerance). Researchers tested 36 teens with ME/CFS and 43 recovered teens, all about 6 months after having infectious mononucleosis. Surprisingly, they found that similar numbers of both groups had difficulty with standing tolerance, suggesting this may not be a key difference between those who recover and those who develop ME/CFS.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Contrasting case definitions for chronic fatigue syndrome, Myalgic Encephalomyelitis/chronic fatigue syndrome and myalgic encephalomyelitis.

Jason, Leonard A, Brown, Abigail, Clyne, Erin et al.·Evaluation & the health professions·2012

This study looked at patients diagnosed with chronic fatigue syndrome (CFS) using an older definition and compared how many of them would also meet two newer, stricter definitions: ME/CFS and ME. Researchers found that patients meeting the newer, stricter definitions had more severe symptoms and greater disability than those who only met the older CFS definition. This suggests that the newer definitions may help doctors identify the most severely affected patients.

Diagnostics

E2 ModerateDiagnosticPEM unclearMethods-Paper

Data mining: comparing the empiric CFS to the Canadian ME/CFS case definition.

Jason, Leonard A, Skendrovic, Beth, Furst, Jacob et al.·Journal of clinical psychology·2012

This study compared two different sets of diagnostic criteria used to identify ME/CFS patients. Researchers used a computer-based analysis technique to test which questions from patient surveys were most helpful in accurately diagnosing the illness. They found that the Canadian criteria correctly identified 87% of ME/CFS patients, while the older empiric criteria identified about 79%, suggesting the Canadian approach may be more effective for diagnosis.

Diagnostics

E2 ModerateCohortPEM unclearCross-Sectional

No evidence for xenotropic murine leukemia-related virus infection in Sweden using internally controlled multiepitope suspension array serology.

Blomberg, Jonas, Blomberg, Fredrik, Sjösten, Anna et al.·Clinical and vaccine immunology : CVI·2012

Researchers tested blood samples from ME/CFS patients and healthy blood donors to see if they had been infected with a mouse virus called XMRV, which had been proposed as a possible cause of ME/CFS. Using a sensitive new testing method that looked for multiple signs of XMRV infection, they found no difference in viral markers between the two groups, suggesting XMRV is not associated with ME/CFS.

No serological evidence for a role of HHV-6 infection in chronic fatigue syndrome.

Burbelo, Peter D, Bayat, Ahmad, Wagner, Jason et al.·American journal of translational research·2012

This study tested whether a virus called HHV-6 might be causing chronic fatigue syndrome (ME/CFS). Researchers compared antibodies (immune system markers) against HHV-6 in people with ME/CFS and healthy controls. They found that both groups had similar levels of HHV-6 antibodies, suggesting this virus is unlikely to be a major cause of ME/CFS.

E2 ModerateCohortPEM not requiredCross-Sectional

Alternative diagnoses to chronic fatigue syndrome in referrals to a specialist service: service evaluation survey.

Devasahayam, Anoop, Lawn, Tara, Murphy, Maurice et al.·JRSM short reports·2012

This study looked at patients referred to a specialist ME/CFS clinic to see how often doctors correctly identified ME/CFS versus other conditions. Researchers found that about half of all referred patients actually had different medical or psychiatric conditions instead of ME/CFS—most commonly sleep disorders or depression. This shows that careful specialist assessment is important to make sure patients get the right diagnosis.

Diagnostics

E2 ModerateBehavioralPEM not requiredObservational

Therapist effects and the dissemination of cognitive behavior therapy for chronic fatigue syndrome in community-based mental health care.

Wiborg, Jan F, Knoop, Hans, Wensing, Michel et al.·Behaviour research and therapy·2012

This study looked at how well cognitive behavior therapy (CBT) for ME/CFS works when delivered by different therapists in regular mental health clinics rather than specialized centers. Researchers found that the individual therapist made a big difference in patient outcomes—accounting for 21% of the improvement variation. The therapist's beliefs about using treatment manuals and the specific clinic where treatment happened both influenced how well patients did.

E2 ModerateCohortPEM not requiredCross-Sectional

Impaired blood pressure variability in chronic fatigue syndrome--a potential biomarker.

Frith, J, Zalewski, P, Klawe, J J et al.·QJM : monthly journal of the Association of Physicians·2012

ME/CFS is often associated with problems in the autonomic nervous system, which controls heart rate and blood pressure. This study measured how heart rate and blood pressure respond to position changes in 68 ME/CFS patients and 68 healthy controls. The researchers found that ME/CFS patients showed abnormal patterns in blood pressure variability that could potentially be used as a diagnostic test.

Autonomic Nervous System

Test effort in persons with Chronic Fatigue Syndrome when assessed using the Validity Indicator Profile.

Cockshell, Susan J, Mathias, Jane L·Journal of clinical and experimental neuropsychology·2012

This study tested whether people with ME/CFS perform poorly on thinking tests because they aren't trying hard enough, or because of the illness itself. Researchers gave 54 people with ME/CFS and 54 healthy people a special test designed to measure effort and intention during testing. The results showed that most people in both groups were trying their best, and very few showed signs of not putting in effort—suggesting that low effort is not the reason people with ME/CFS struggle with cognitive tasks.

Cognitive Impairment

Immunophenotyping in post-giardiasis functional gastrointestinal disease and chronic fatigue syndrome.

Hanevik, Kurt, Kristoffersen, Einar K, Sørnes, Steinar et al.·BMC infectious diseases·2012

This study looked at immune system changes in people who developed chronic fatigue and gut problems after a Giardia infection. Researchers found that people with post-infectious chronic fatigue had lower levels of natural killer (NK) cells, which are important for fighting infections. The more severe someone's fatigue and stomach symptoms were, the lower their NK cells tended to be.

Cytokine expression profiles of immune imbalance in post-mononucleosis chronic fatigue.

Broderick, Gordon, Katz, Ben Z, Fernandes, Henrique et al.·Journal of translational medicine·2012

This study followed 301 teenagers who had infectious mononucleosis caused by the Epstein-Barr virus (EBV) for two years. Some developed ME/CFS after their infection while others recovered completely. Researchers measured multiple immune molecules called cytokines in the blood to see if they could identify a pattern that distinguishes people with post-infectious ME/CFS from those who fully recovered.

Response to valganciclovir in chronic fatigue syndrome patients with human herpesvirus 6 and Epstein-Barr virus IgG antibody titers.

Watt, Tessa, Oberfoell, Stephanie, Balise, Raymond et al.·Journal of medical virology·2012

This study looked at whether a antiviral medication called valganciclovir could help ME/CFS patients who had high levels of antibodies to two common viruses: HHV-6 and EBV. Sixty-one patients took the medication for varying lengths of time, and about half reported at least 30% improvement in their physical energy and thinking abilities. Interestingly, the improvement didn't depend on how high their antibody levels were at the start—patients improved simply from taking the medication, and those who took it longer did better.

Predictors of Fatigue among Patients with Chronic Fatigue Syndrome.

Jason, Leonard A, Brown, Molly, Evans, Meredyth et al.·Journal Of Human Behavior In The Social Environment·2012

This study asked ME/CFS patients to keep detailed activity logs to understand what triggers their fatigue. Researchers looked at what patients were doing, what they had been doing 30 minutes earlier, and their fatigue levels to find patterns. The study suggests that tracking daily activities can help doctors and patients see which activities are most connected to fatigue flare-ups.

[Effects of tuina on the mechanical properties of skeletal muscles of four limbs in patients with chronic fatigue syndrome].

Liu, Kun-Peng, Fang, Min, Jiang, Shu-Yun·Zhongguo Zhong xi yi jie he za zhi Zhongguo Zhongxiyi jiehe zazhi = Chinese journal of integrated traditional and Western medicine·2012

This study tested whether tuina (a traditional Chinese massage therapy) could help ME/CFS patients regain muscle strength and reduce fatigue. Sixty people participated—30 with ME/CFS and 30 healthy controls. After 10 sessions of tuina therapy, ME/CFS patients showed improvements in muscle strength measurements and reported feeling less fatigued, though their muscles remained weaker than those of healthy people.