Evidence browser

E2 ModerateCohortPEM requiredCross-Sectional

Cytokine expression provides clues to the pathophysiology of Gulf War illness and myalgic encephalomyelitis.

Khaiboullina, Svetlana F, DeMeirleir, Kenny L, Rawat, Shanti et al.·Cytokine·2015

This study looked at chemical messengers in the blood called cytokines to understand Gulf War illness (GWI) and ME/CFS better. Researchers found that certain cytokines could identify ME/CFS patients very well, but were less reliable for GWI patients. The findings suggest that while GWI and ME/CFS share many similar symptoms, they may have different underlying immune system problems.

BiomarkersImmune System

A new case definition of Neuro-Inflammatory and Oxidative Fatigue (NIOF), a neuroprogressive disorder, formerly known as chronic fatigue syndrome or Myalgic Encephalomyelitis: results of multivariate pattern recognition methods and external validation by neuro-immune biomarkers.

Maes, Michael·Neuro endocrinology letters·2015

This study looked at whether ME/CFS could be better understood by examining specific blood markers related to inflammation, oxidative stress, and immune activation. Researchers found two distinct groups of people with chronic fatigue—one group had significantly higher levels of problematic immune markers and inflammatory signs. The study proposes a new way to identify ME/CFS based on fatigue plus at least four of these symptoms: muscle tension, memory problems, sleep issues, digestive problems, headaches, or flu-like feelings.

BiomarkersImmune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Response to vitamin B12 and folic acid in myalgic encephalomyelitis and fibromyalgia.

Regland, Björn, Forsmark, Sara, Halaouate, Lena et al.·PloS one·2015

This study looked at 38 ME/CFS patients who were receiving vitamin B12 injections and oral folic acid to see how well this treatment worked for them. Patients who improved the most received more frequent injections at higher doses, took more folic acid, and were less likely to use strong pain medications like opioids. The researchers found that this treatment combination showed real benefits for some patients, particularly when carefully matched to individual needs.

Interventions

A comparison of patients with Q fever fatigue syndrome and patients with chronic fatigue syndrome with a focus on inflammatory markers and possible fatigue perpetuating cognitions and behaviour.

Keijmel, Stephan P, Saxe, Johanna, van der Meer, Jos W M et al.·Journal of psychosomatic research·2015

This study compared people with Q fever fatigue syndrome (a fatigue illness that develops after a specific infection) with people with ME/CFS to see if they were similar. Researchers found that both groups experienced similar levels of fatigue and emotional distress, but had some differences in their backgrounds and how they thought about their symptoms. The study suggests that physical activity might play a role in fatigue for both conditions, and that treatments focusing on behavior changes could potentially help people with Q fever fatigue syndrome.

Frequent IgG subclass and mannose binding lectin deficiency in patients with chronic fatigue syndrome.

Guenther, Sabrina, Loebel, Madlen, Mooslechner, Agnes A et al.·Human immunology·2015

This study looked at immune system proteins called antibodies and a molecule called mannose binding lectin (MBL) in 300 people with ME/CFS. The researchers found that about 25% of patients had lower-than-normal levels of certain antibodies, while another 25% had higher-than-normal levels. Additionally, 15% had low MBL levels, compared to only 6% in healthy people. These immune defects were connected to frequent respiratory infections in ME/CFS patients.

E2 ModerateCohortPEM unclearLongitudinal

Longitudinal analysis of immune abnormalities in varying severities of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis patients.

Hardcastle, Sharni Lee, Brenu, Ekua Weba, Johnston, Samantha et al.·Journal of translational medicine·2015

This study tracked immune system changes in 42 ME/CFS patients (divided into moderate and severe groups) and 18 healthy controls over 6 months. Researchers used blood tests to count different types of immune cells. They found that people with severe ME/CFS had noticeably different immune cell patterns than those with moderate ME/CFS or healthy controls, suggesting the immune system may work differently depending on how severe the illness is.

BiomarkersImmune System

Prolonged fatigue in Ukraine and the United States: Prevalence and risk factors.

Friedberg, Fred, Tintle, Nathan, Clark, Jake et al.·Fatigue : biomedicine, health & behavior·2015

This study compared how common prolonged, disabling fatigue is in Ukraine versus the United States by surveying thousands of people in both countries. Researchers found that prolonged fatigue was more common in Ukraine (5.2%) than in the U.S. (3.7%), and identified different risk factors in each country—such as socioeconomic status, mood disorders, and various health conditions. Importantly, about one-fifth of people with prolonged fatigue had no other diagnosed medical or mental health condition.

Timed loaded standing in female chronic fatigue syndrome compared with other populations.

Eyskens, Jan B, Nijs, Jo, D'Août, Kristiaan et al.·Journal of rehabilitation research and development·2015

Researchers tested how long women with ME/CFS could hold small weights with their arms extended straight out—a test that measures muscle endurance in the arms and trunk. Women with ME/CFS performed significantly worse than healthy women and even worse than older women with osteoporosis, suggesting a specific weakness pattern in ME/CFS. This finding could help guide rehabilitation programs that focus on movement quality rather than just building strength.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredObservational

Perceived fatigue is highly prevalent and debilitating in patients with mitochondrial disease.

Gorman, Gráinne S, Elson, Joanna L, Newman, Jane et al.·Neuromuscular disorders : NMD·2015

This study found that fatigue is very common and severely disabling in people with mitochondrial disease. About 62% of patients reported excessive fatigue, and 32% experienced severe fatigue that significantly limited their daily activities—levels comparable to fatigue in ME/CFS patients. The researchers surveyed 132 patients and compared their fatigue levels to healthy people and ME/CFS patients to understand how widespread and serious this problem is.

Chronic fatigue syndrome: Features of a population of patients from northern Italy.

Capelli, E, Lorusso, L, Ghitti, M et al.·International journal of immunopathology and pharmacology·2015

This Italian study looked at medical records from 82 ME/CFS patients to understand what might trigger the illness and how it differs between men and women. Researchers found that patients who developed the condition at younger ages were more likely to have autoimmune problems (where the immune system attacks the body's own cells). The study also examined family members to see if certain events or conditions ran in families.

The Health-Related Quality of Life for Patients with Myalgic Encephalomyelitis / Chronic Fatigue Syndrome (ME/CFS).

Falk Hvidberg, Michael, Brinth, Louise Schouborg, Olesen, Anne V et al.·PloS one·2015

This study measured how ME/CFS affects quality of life using a standard health questionnaire given to Danish ME/CFS patients. The results show that people with ME/CFS report significantly lower quality of life (a score of 0.47 out of 1.0) compared to the general population (0.85), and this impact is worse than 20 other health conditions studied. Even after accounting for other illnesses patients might have, ME/CFS itself was shown to cause substantial harm to daily life and wellbeing.

Evidence for the existence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) with and without abdominal discomfort (irritable bowel) syndrome.

Maes, Michael, Leunis, Jean-Claude, Geffard, Michel et al.·Neuro endocrinology letters·2014

This study found that many people with ME/CFS experience stomach and digestive problems, and this appears to be linked to bacteria from the gut leaking into the bloodstream. Researchers identified two groups of ME/CFS patients: those with significant abdominal discomfort and those without. The group with digestive symptoms showed higher levels of immune responses to gut bacteria, suggesting their intestinal barrier may be more permeable.

E2 ModerateBehavioralPEM not requiredCase-Control

Comorbidity of postural orthostatic tachycardia syndrome and chronic fatigue syndrome in an Australian cohort.

Reynolds, G K, Lewis, D P, Richardson, A M et al.·Journal of internal medicine·2014

This study looked at patients with ME/CFS to see how many also have POTS (a condition where heart rate increases too much when standing). The researchers found that about 1 in 9 ME/CFS patients also had POTS, and these patients were younger, got sick more recently, and found it much harder to stand for long periods compared to ME/CFS patients without POTS.

Autonomic Nervous System

Dimensions of pure chronic fatigue: psychophysical, cognitive and biological correlates in the chronic fatigue syndrome.

Neu, Daniel, Mairesse, Olivier, Montana, Xavier et al.·European journal of applied physiology·2014

This study compared 16 people with ME/CFS to 14 healthy controls to understand fatigue better. Researchers measured attention, reaction time, muscle strength, sleep patterns, and immune markers (cytokines). They found that people with ME/CFS had cognitive problems, slower reactions, weaker grip strength, and higher levels of certain inflammatory markers—but their sleep time was actually similar to controls.

E2 ModeratePEM unclearBiobank-Resource

No association found between the detection of either xenotropic murine leukemia virus-related virus or polytropic murine leukemia virus and chronic fatigue syndrome in a blinded, multi-site, prospective study by the establishment and use of the SolveCFS BioBank.

Irlbeck, David M, Vernon, Suzanne D, McCleary, K Kimberly et al.·BMC research notes·2014

Researchers investigated whether two viruses (XMRV and pMLV) were present in people with ME/CFS, as had been suggested by earlier studies. They collected blood samples from people with ME/CFS and healthy people across five different U.S. locations and used sensitive testing methods to look for these viruses. They found no meaningful difference in virus detection between the two groups, and the virus sequences they did find appeared to be contamination from lab materials rather than real infections.

Use of single-nucleotide polymorphisms (SNPs) to distinguish gene expression subtypes of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME).

Shimosako, Nana, Kerr, Jonathan R·Journal of clinical pathology·2014

This study looked at small variations in DNA (called SNPs) from people with ME/CFS to see if these genetic differences could help identify different subtypes of the condition. Researchers compared DNA from 108 ME/CFS patients with 17 people with depression and 68 healthy people. They found that certain genetic variations were more common in ME/CFS patients and that different combinations of these variations appeared to match different subtypes of the illness.

Biomarkers