Evidence browser

E2 ModerateBehavioralPEM not requiredCross-Sectional

Sexual dysfunction as related to severity of fatigue in women with CFS.

Blazquez, A, Ruiz, E, Vazquez, A et al.·Journal of sex & marital therapy·2008

This study looked at whether sexual function problems are connected to fatigue severity in women with ME/CFS. Researchers compared 27 women with ME/CFS to 15 healthy women and used questionnaires to measure sexual satisfaction, interest, and comfort. They found that women with more severe fatigue reported more sexual problems, including less satisfaction, avoiding sexual activity, and viewing sex negatively.

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 ModerateCohortPEM unclearCross-Sectional

Evidence for T-helper 2 shift and association with illness parameters in chronic fatigue syndrome (CFS).

Torres-Harding, Susan, Sorenson, Matthew, Jason, Leonard A et al.·Bulletin of the IACFS/ME·2008

This study looked at immune system differences in people with ME/CFS by measuring two types of immune cells called Th1 and Th2. Researchers found that people with ME/CFS who had a stronger shift toward Th2 immune responses also reported worse sleep quality and had higher stress hormone levels in their saliva. This suggests that immune system imbalances might be connected to some of the troubling symptoms people with ME/CFS experience.

Immunoassay with cytomegalovirus early antigens from gene products p52 and CM2 (UL44 and UL57) detects active infection in patients with chronic fatigue syndrome.

Beqaj, S H, Lerner, A M, Fitzgerald, J T·Journal of clinical pathology·2008

This study tested a new blood test method to detect active cytomegalovirus (CMV) infection in ME/CFS patients. The new test, called Copalis, was more sensitive than standard tests at finding signs of active CMV infection, detecting it in about 12% of CMV-exposed patients compared to only 2% with the older method. The researchers suggest this improved test could help identify a subset of ME/CFS patients who have active CMV infection.

E2 ModerateCohortPEM unclearCross-Sectional

The prevalence of generalized soft tissue rheumatic conditions in Turkish medical students.

Eyigor, Sibel, Ozdedeli, Selcen, Durmaz, Berrin·Journal of clinical rheumatology : practical reports on rheumatic & musculoskeletal diseases·2008

This study looked at how common soft tissue pain conditions—including fibromyalgia, muscle pain, and joint hypermobility—are among medical students in Turkey. Researchers found that about 1 in 5 students had one of these conditions, with women affected much more often than men. Students with these conditions reported lower quality of life, especially in physical functioning and energy levels.

Prevalence of chronic widespread pain and chronic fatigue syndrome in Korean livestock raisers.

Kim, Seong-Ho, Lee, Kwan, Lim, Hyun-Sul·Journal of occupational health·2008

This study looked at how common chronic widespread pain and chronic fatigue syndrome (ME/CFS) are among Korean livestock farmers. Researchers surveyed farmers to understand whether their work environments and conditions might be connected to these conditions. The study helps show that ME/CFS affects not just office workers, but also people in physically demanding jobs like farming.

Low-grade inflammation and arterial wave reflection in patients with chronic fatigue syndrome.

Spence, Vance A, Kennedy, Gwen, Belch, Jill J F et al.·Clinical science (London, England : 1979)·2008

This study found that people with ME/CFS have stiffer arteries and higher levels of inflammation and oxidative stress (cellular damage) compared to healthy people. These cardiovascular changes are associated with each other and may increase the risk of future heart problems in people with ME/CFS.

Etiology of chronic fatigue syndrome: testing popular hypotheses using a national birth cohort study.

Harvey, Samuel B, Wadsworth, Michael, Wessely, Simon et al.·Psychosomatic medicine·2008

This study followed nearly 5,000 people from birth into their 50s to understand what causes ME/CFS. Researchers found that people who exercised more throughout their life—and continued exercising even as they felt increasingly tired—were more likely to develop ME/CFS later on. The study suggests that continuing to push yourself physically while experiencing growing fatigue may play a role in developing this condition.

Increase in prefrontal cortical volume following cognitive behavioural therapy in patients with chronic fatigue syndrome.

de Lange, Floris P, Koers, Anda, Kalkman, Joke S et al.·Brain : a journal of neurology·2008

This study found that ME/CFS patients have less brain tissue volume in certain areas compared to healthy people, but this loss can partially reverse with cognitive behavioural therapy (CBT). Patients who received CBT showed improvement in their symptoms, physical activity, and thinking speed, and their brain scans revealed increased grey matter volume in the prefrontal cortex (the front part of the brain involved in decision-making). This suggests that some of the brain changes seen in ME/CFS may not be permanent and could improve with effective treatment.

Cognitive Impairment

Predictors of persistent and new-onset fatigue in adolescent girls.

ter Wolbeek, Maike, van Doornen, Lorenz J P, Kavelaars, Annemieke et al.·Pediatrics·2008

This study followed 653 teenage girls over one year to understand why some develop long-lasting fatigue while others recover. Researchers found that about 26% of girls who were severely fatigued at the start remained fatigued throughout the year. Depression, anxiety, low physical activity, and poor sleep were linked to persistent or new fatigue, suggesting that emotional health and lifestyle habits play important roles in fatigue development.

Sleep

E2 ModerateTrialPEM not requiredRCT

Gait characteristics of subjects with chronic fatigue syndrome and controls at self-selected and matched velocities.

Paul, Lorna, Rafferty, Danny, Wood, Leslie et al.·Journal of neuroengineering and rehabilitation·2008

People with ME/CFS often walk differently than healthy people. Researchers tracked how 12 people with ME/CFS and 12 healthy controls walked, measuring their leg and ankle movements. People with ME/CFS walked slower and had different ankle movements, especially when walking at their own comfortable pace.

Breathing retraining in patients with chronic fatigue syndrome: a pilot study.

Nijs, Jo, Adriaens, Jan, Schuermans, Daniel et al.·Physiotherapy theory and practice·2008

This small study looked at whether some ME/CFS patients have a breathing pattern problem where their chest and belly don't move together smoothly (asynchronous breathing). Researchers found that about 1 in 4 ME/CFS patients had this pattern, and a single 20-30 minute breathing retraining session helped these patients breathe more slowly and deeply right after the session.

E2 ModerateCohortPEM not requiredCase-Control

Diffuse noxious inhibitory control is delayed in chronic fatigue syndrome: an experimental study.

Meeus, Mira, Nijs, Jo, Van de Wauwer, Naomi et al.·Pain·2008

This study tested how quickly the body's natural pain-blocking system kicks in when ME/CFS patients experience heat pain compared to healthy people. Researchers immersed participants' arms in warm water and tracked pain levels over time. They found that people with ME/CFS have stronger pain sensations overall, and their bodies take longer to activate the natural pain-suppression mechanism that normally reduces pain during ongoing stimulation.

Pain and Sensitization

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic pain and fatigue: Associations with religion and spirituality.

Baetz, M, Bowen, R·Pain research & management·2008

This study looked at whether religion and spiritual beliefs affect how people experience chronic pain and fatigue, including ME/CFS. Using data from over 37,000 Canadians, researchers found that people who actively practice religion had fewer chronic pain and fatigue symptoms, while those who were spiritual but didn't attend religious services were more likely to have these conditions. People with chronic pain and fatigue often used prayer and spiritual support to cope, and those combining both religion and spirituality reported better emotional well-being.

E2 ModerateCohortPEM unclearCross-Sectional

Physical health 25 years later: the predictive ability of neuroticism.

Charles, Susan Turk, Gatz, Margaret, Kato, Kenji et al.·Health psychology : official journal of the Division of Health Psychology, American Psychological Association·2008

This study followed over 21,000 people for 25 years to see if personality traits measured in 1973 could predict physical health problems in 1998–2002. The researchers found that people who scored higher on neuroticism—a trait involving worry, emotional sensitivity, and stress—were more likely to report having chronic conditions, including chronic fatigue syndrome. However, when family history was considered, some of these connections weakened, suggesting that genetics may partly explain why certain personality traits and health problems run in families.

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 ModerateCohortPEM not requiredCase-Control

Genetic evaluation of the serotonergic system in chronic fatigue syndrome.

Smith, Alicia K, Dimulescu, Irina, Falkenberg, Virginia R et al.·Psychoneuroendocrinology·2008

This study looked at genes related to serotonin (a brain chemical) to see if certain genetic variations are more common in people with ME/CFS. Researchers compared 40 ME/CFS patients with 97 control subjects and found that specific genetic markers in the HTR2A gene were associated with ME/CFS and with severity of fatigue and disability. These genetic variations may increase how active the serotonin system is in the brain, which could play a role in ME/CFS.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Fatigue among Spanish- and English-speaking Latinos.

Torres-Harding, Susan R, Mason-Shutter, Jennifer, Jason, Leonard A·Social work in public health·2008

This study looked at fatigue levels in Latino communities in Chicago, comparing people who speak English at home with those who speak Spanish at home. Researchers found that English-speaking Latinos reported higher levels of fatigue than Spanish-speaking Latinos. The difference remained even after accounting for other factors like age, income, and education, suggesting that cultural factors related to language and adaptation to a new country may play a role in how severe fatigue becomes.

E2 ModerateCohortPEM unclearObservational

Normalization of leaky gut in chronic fatigue syndrome (CFS) is accompanied by a clinical improvement: effects of age, duration of illness and the translocation of LPS from gram-negative bacteria.

Maes, Michael, Leunis, Jean-Claude·Neuro endocrinology letters·2008

This study tested whether taking natural anti-inflammatory supplements (glutamine, N-acetyl cysteine, and zinc) along with a special diet could help ME/CFS patients whose intestines had become too permeable ("leaky gut"). Researchers measured immune markers in the blood before and after 10-14 months of treatment and found that 24 out of 41 patients improved significantly, with the best results in younger patients and those with shorter illness duration.