Evidence browser

Postinfectious fatigue in adolescents and physical activity.

Huang, Yue, Katz, Ben Z, Mears, Cynthia et al.·Archives of pediatrics & adolescent medicine·2010

This study followed 301 teenagers with infectious mononucleosis (mono) for 2 years, comparing those who developed chronic fatigue syndrome (CFS) with those who recovered normally. Adolescents with post-infection CFS reported much more severe fatigue and needed more daytime sleep than their peers, even though their overall activity levels looked similar on paper. The key finding suggests that teenagers with CFS after mono may be forcing themselves to stay active like their friends, but at a significant physical cost in terms of exhaustion and sleep needs.

Increased ventricular lactate in chronic fatigue syndrome measured by 1H MRS imaging at 3.0 T. II: comparison with major depressive disorder.

Murrough, James W, Mao, Xiangling, Collins, Katherine A et al.·NMR in biomedicine·2010

This study used a special type of brain imaging called MRI to measure a substance called lactate in the fluid around the brain of people with ME/CFS. The researchers found that people with ME/CFS had significantly higher lactate levels compared to healthy people and people with depression. Interestingly, people with depression had normal lactate levels, suggesting this finding may be specific to ME/CFS and not just a symptom of mental illness.

Biomarkers

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

Katz, Ben Z, Boas, Steven, Shiraishi, Yukiko et al.·The Journal of pediatrics·2010

After infectious mononucleosis, some teenagers develop ME/CFS. Researchers compared how well teenagers with ME/CFS could exercise compared to teenagers who recovered normally from mono. Teenagers with ME/CFS showed lower oxygen use and heart efficiency during exercise tests, even though they looked the same as healthy teens in other ways.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Childhood maltreatment and migraine (part III). Association with comorbid pain conditions.

Tietjen, Gretchen E, Brandes, Jan L, Peterlin, B Lee et al.·Headache·2010

This study looked at people with migraine who came to headache clinics and asked whether childhood trauma (abuse or neglect) was connected to having multiple pain conditions at the same time, including chronic fatigue syndrome. They found that people who experienced emotional abuse or physical neglect as children were more likely to have multiple pain conditions as adults, even after accounting for depression and anxiety.

Pain and Sensitization

Failure to detect the novel retrovirus XMRV in chronic fatigue syndrome.

Erlwein, Otto, Kaye, Steve, McClure, Myra O et al.·PloS one·2010

In 2009, researchers reported finding a virus called XMRV in about two-thirds of ME/CFS patients in the US, raising hopes for a breakthrough in understanding the disease. This UK study tested blood samples from 186 ME/CFS patients to see if they also carried this virus, but found no evidence of XMRV in any of them. The results suggest the virus may not be common in ME/CFS patients in Europe, or that earlier findings may have been specific to certain populations.

Microbial infections in eight genomic subtypes of chronic fatigue syndrome/myalgic encephalomyelitis.

Zhang, Lihan, Gough, John, Christmas, David et al.·Journal of clinical pathology·2010

This study looked at blood samples from ME/CFS patients to identify different genetic subtypes based on how 88 genes were turned on or off. Researchers found that ME/CFS patients had distinct genetic patterns that were different from healthy people and those with depression. They also discovered that different viral infections—particularly Epstein-Barr virus and enterovirus—were linked to different genetic subtypes of ME/CFS.

Immune System

E2 ModerateCohortPEM unclearCross-Sectional

Reduced heart rate variability predicts poor sleep quality in a case-control study of chronic fatigue syndrome.

Burton, A R, Rahman, K, Kadota, Y et al.·Experimental brain research·2010

People with ME/CFS often report poor sleep quality. This study measured heart rate patterns during sleep in 20 patients with ME/CFS and 20 healthy controls, finding that ME/CFS patients had much lower heart rate variability (natural changes in heart rate) during sleep. The researchers concluded that this reduced variability—suggesting the nervous system stays "on high alert" even at night—is closely linked to their sleep problems.

Autonomic Nervous System

Classification of myalgic encephalomyelitis/chronic fatigue syndrome by types of fatigue.

Jason, Leonard A, Boulton, Aaron, Porter, Nicole S et al.·Behavioral medicine (Washington, D.C.)·2010

This study looked at 100 people with ME/CFS to see if they experience fatigue in different ways. Researchers used a questionnaire to measure five different types of fatigue and found that patients naturally fell into distinct groups based on their fatigue patterns. The results show that ME/CFS affects people differently—some experience mostly one type of fatigue heavily, while others have combinations of different fatigue types.

E2 ModerateCohortPEM unclearObservational

Fibromyalgia and related conditions: electromyogram profile during isometric muscle contraction.

Maquet, Didier, Croisier, Jean-Louis, Dupont, Catherine et al.·Joint bone spine·2010

This study measured how muscles work during sustained effort by recording electrical signals from shoulder muscles in people with fibromyalgia, ME/CFS, depression, and healthy controls. People with fibromyalgia stopped their muscle contraction much earlier than others and showed a distinctive electrical pattern suggesting their muscles gave up prematurely. Importantly, ME/CFS patients showed muscle patterns very similar to healthy people, not the abnormal pattern seen in fibromyalgia.

Xenotropic murine leukemia virus-related gammaretrovirus in respiratory tract.

Fischer, Nicole, Schulz, Claudia, Stieler, Kristin et al.·Emerging infectious diseases·2010

Researchers looked for a virus called XMRV in respiratory samples (like saliva or mucus) from healthy and immunocompromised people. They found viral traces in a small percentage of healthy people (2-3%) and a higher percentage of immunocompromised people (10%). This study was one of several investigating whether XMRV might be linked to ME/CFS, though the findings were modest.

Immune System

E2 ModerateCohortPEM requiredCross-Sectional

Postexertional malaise in women with chronic fatigue syndrome.

VanNess, J Mark, Stevens, Staci R, Bateman, Lucinda et al.·Journal of women's health (2002)·2010

This study looked at how women with ME/CFS recover from exercise compared to healthy women. After a single exercise test, 85% of healthy women felt completely back to normal within 24 hours, but none of the women with ME/CFS did—in fact, most took much longer to recover, experiencing worsening fatigue, pain, cognitive problems, and other symptoms. This research confirms that postexertional malaise is a real and serious condition that makes recovery from physical activity dramatically different for people with ME/CFS.

Sleep is not disrupted by exercise in patients with chronic fatigue syndromes.

Togo, Fumiharu, Natelson, Benjamin H, Cherniack, Neil S et al.·Medicine and science in sports and exercise·2010

Researchers studied whether exercise makes sleep worse in ME/CFS patients, since many report feeling much sicker after activity. They measured sleep quality using overnight sleep monitoring in ME/CFS patients and healthy controls, both before and after an exercise test. The main finding: exercise did not make sleep worse for ME/CFS patients, and about half actually slept better after exercising.

Absence of xenotropic murine leukemia virus-related virus in blood cells of men at risk for and infected with HIV.

Kunstman, Kevin J, Bhattacharya, Tanmoy, Flaherty, John et al.·AIDS (London, England)·2010

Researchers tested nearly 1,000 men for a virus called XMRV that had been found in some ME/CFS patients. They found no evidence of this virus in any of the men tested, even though the virus had been detected in a small percentage of healthy people from similar geographic areas. This suggests that if XMRV is linked to ME/CFS, it may only occur in certain populations.

Pain and SensitizationSleep

Interstitial cystitis/painful bladder syndrome and associated medical conditions with an emphasis on irritable bowel syndrome, fibromyalgia and chronic fatigue syndrome.

Nickel, J Curtis, Tripp, Dean A, Pontari, Michel et al.·The Journal of urology·2010

This study looked at how often bladder pain syndrome occurs alongside other conditions like irritable bowel syndrome, fibromyalgia, and ME/CFS. Researchers found that people with bladder pain syndrome were much more likely to have these other conditions compared to healthy controls. Importantly, people who had multiple overlapping conditions experienced worse pain, sleep problems, depression, and lower quality of life than those with just one condition.

E2 ModerateCohortPEM unclearCross-Sectional

Chronic fatigue syndrome is associated with metabolic syndrome: results from a case-control study in Georgia.

Maloney, Elizabeth M, Boneva, Roumiana S, Lin, Jin-Mann S et al.·Metabolism: clinical and experimental·2010

This study found that people with ME/CFS are twice as likely to have metabolic syndrome—a cluster of conditions including high blood pressure, high blood sugar, excess belly fat, and abnormal cholesterol levels—compared to healthy people. The more metabolic factors someone had, the worse their fatigue tended to be. This suggests that metabolic problems may be connected to ME/CFS severity.

Energy Metabolism

No evidence for XMRV in German CFS and MS patients with fatigue despite the ability of the virus to infect human blood cells in vitro.

Hohn, Oliver, Strohschein, Kristin, Brandt, Alexander U et al.·PloS one·2010

Researchers tested blood samples from German ME/CFS patients, multiple sclerosis patients with fatigue, and healthy people to see if a virus called XMRV was present. They looked for both antibodies (immune system markers) and viral genetic material. They found no evidence of XMRV in any of the groups, suggesting this virus is not associated with ME/CFS or MS-related fatigue in Germany.

Immune System

Pain and SensitizationSleep

Adolescent offspring of mothers with chronic fatigue syndrome.

Smith, Mark S, Buchwald, Dedra S, Bogart, Andy et al.·The Journal of adolescent health : official publication of the Society for Adolescent Medicine·2010

This study looked at whether teenagers whose mothers have ME/CFS are more likely to develop ME/CFS themselves or experience fatigue and other related symptoms. Researchers compared 26 teenagers with mothers who had ME/CFS to 45 teenagers whose mothers were healthy. While teenagers with affected mothers showed higher rates of prolonged fatigue and ME/CFS diagnosis, the differences were small and not statistically proven.

E2 ModerateCohortPEM requiredObservational

Unravelling the nature of postexertional malaise in myalgic encephalomyelitis/chronic fatigue syndrome: the role of elastase, complement C4a and interleukin-1beta.

Nijs, J, Van Oosterwijck, J, Meeus, M et al.·Journal of internal medicine·2010

This study looked at what happens in the blood after people with ME/CFS exercise. Researchers compared 22 women with ME/CFS to 22 healthy women and measured specific immune markers (elastase, IL-1beta, and complement C4a) before and after two different types of exercise. Both types of exercise triggered postexertional malaise (a worsening of symptoms after activity) in the ME/CFS group, but surprisingly, the immune markers they measured didn't show significant changes in either group.

Immune SystemPost-Exertional Malaise