ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

721–729 of 729 studies

E3 PreliminaryMechanismPEM not requiredObservational

Acylcarnitine deficiency in chronic fatigue syndrome.

Kuratsune, H, Yamaguti, K, Takahashi, M et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1994

This study found that people with ME/CFS have lower levels of acylcarnitine, a substance that helps muscles produce energy, in their blood. Because acylcarnitine plays an important role in how muscles use energy, this deficiency might explain why ME/CFS patients experience fatigue, muscle pain, and weakness. Importantly, acylcarnitine levels tended to improve as patients recovered, suggesting it could be useful for tracking disease severity.

BiomarkersPost-Exertional Malaise

E3 PreliminaryCommentaryPEM unclearEditorial

The grey area of effort syndrome and hyperventilation: from Thomas Lewis to today.

Nixon, P G·Journal of the Royal College of Physicians of London·1993

This article reviews the historical concept of 'effort syndrome'—a condition where the body loses its ability to handle physical exertion due to chemical imbalances, particularly in how the body buffers acids produced during exercise. The author argues that this old diagnosis remains relevant today and should be considered when evaluating chronic fatigue and other unexplained illnesses, especially when emotional stress and overbreathing (hyperventilation) are present.

Energy MetabolismPost-Exertional Malaise

E3 PreliminaryBehavioralPEM unclearConference-Abstract

Muscle histopathology and physiology in chronic fatigue syndrome.

Edwards, R H, Gibson, H, Clague, J E et al.·Ciba Foundation symposium·1993

Researchers examined muscle tissue from 108 ME/CFS patients and 22 healthy people using microscopes to look for structural damage, and tested muscle strength before and after exercise. They found no consistent muscle damage that explained fatigue symptoms, and muscle strength worked normally even after exercise. The study suggests ME/CFS is not caused by a primary muscle disease.

Post-Exertional Malaise

E3 PreliminaryReviewPEM requiredReview-Narrative

Clinical presentation of chronic fatigue syndrome.

Komaroff, A L·Ciba Foundation symposium·1993

ME/CFS is a long-lasting illness that causes severe tiredness lasting at least six months, along with other symptoms like fever, sore throat, joint pain, and worsening after physical activity. While some symptoms can look like mental health conditions, ME/CFS has physical features—like sudden onset following a flu-like illness and post-exertional exhaustion—that suggest it involves real biological problems. This condition significantly impacts people's ability to work, study, and care for themselves.

Post-Exertional Malaise

E3 PreliminaryReviewPEM not requiredReview-Narrative

Chronic fatigue syndrome.

McCluskey, D R, Riley, M S·Comprehensive therapy·1992

ME/CFS likely involves multiple different problems happening in the body at the same time, rather than one single cause. Most patients get sick after a viral infection, but scientists haven't found clear evidence the virus stays in the body long-term. People with ME/CFS have real physical limitations in how much exercise they can do, and they may perceive their own effort and tiredness differently than healthy people do.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM unclearObservational

Skeletal muscle metabolism in the chronic fatigue syndrome. In vivo assessment by 31P nuclear magnetic resonance spectroscopy.

Wong, R, Lopaschuk, G, Zhu, G et al.·Chest·1992

This study used a special imaging technique (31P NMR spectroscopy) to examine how muscles use energy during exercise in people with ME/CFS compared to healthy volunteers. Patients with ME/CFS became exhausted much faster during exercise (about 8 minutes versus 11 minutes) and had lower levels of ATP, the main energy molecule muscles use. The patterns of energy use looked similar between groups, but happened much more quickly in the ME/CFS group.

Post-Exertional Malaise

E3 PreliminaryCohortPEM unclearCross-Sectional

[Symptoms, signs and laboratory findings in patients with chronic fatigue syndrome].

Kuratsune, H, Yamaguti, K, Hattori, H et al.·Nihon rinsho. Japanese journal of clinical medicine·1992

This study examined 59 patients with ME/CFS to identify common symptoms and laboratory abnormalities. The main findings were that patients experienced prolonged fatigue after exercise, headaches, sleep problems, and mild fevers. Researchers found that ME/CFS patients had low levels of a substance called acylcarnitine in their muscles, which may help explain why their bodies struggle to produce energy and why they experience muscle pain and worsening symptoms after activity.

BiomarkersPost-Exertional Malaise

E3 PreliminaryCommentaryPEM not requiredEditorial

Chronic fatigue syndrome: issues in the diagnosis and estimation of incidence.

Armon, C, Kurland, L T·Reviews of infectious diseases·1991

This article examines how ME/CFS is diagnosed and points out problems with the current definition used by doctors. The authors identified several issues: the definition doesn't clearly address what happens when patients do too much activity, it doesn't specify how much rest is needed, and it may miss cases in poorer communities. They suggest a new flowchart that could help identify different types of ME/CFS and potentially help some patients avoid developing the condition.

Post-Exertional Malaise

E3 PreliminaryReviewPEM not requiredReview-Narrative

Physiologic measurement of exercise and fatigue with special reference to chronic fatigue syndrome.

Lewis, S F, Haller, R G·Reviews of infectious diseases·1991

This review article explains how scientists measure exercise capacity and fatigue in the body. It describes three key concepts: aerobic fitness (how efficiently your heart and muscles use oxygen), muscle strength (your muscles' ability to produce force), and fatigue (the loss of strength that happens during activity). The authors discuss how these measurements might help us better understand what happens in ME/CFS when patients experience excessive fatigue.

Post-Exertional Malaise

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Evidence browser

Acylcarnitine deficiency in chronic fatigue syndrome.

The grey area of effort syndrome and hyperventilation: from Thomas Lewis to today.

Muscle histopathology and physiology in chronic fatigue syndrome.

Clinical presentation of chronic fatigue syndrome.

Chronic fatigue syndrome.

Skeletal muscle metabolism in the chronic fatigue syndrome. In vivo assessment by 31P nuclear magnetic resonance spectroscopy.

[Symptoms, signs and laboratory findings in patients with chronic fatigue syndrome].

Chronic fatigue syndrome: issues in the diagnosis and estimation of incidence.

Physiologic measurement of exercise and fatigue with special reference to chronic fatigue syndrome.

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