ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

3721–3740 of 6,161 studies

E2 ModerateCohortPEM not requiredObservational

Asthenic symptoms in a rural family practice. Epidemiologic characteristics and a proposed classification.

Shahar, E, Lederer, J·The Journal of family practice·1990

This study looked at fatigue and weakness complaints in a rural doctor's office over 10 years. Researchers found that about 1 in 3 patients reported these symptoms at some point, with more women affected than men. Most cases improved on their own, and doctors often couldn't identify a specific cause.

E2 ModerateCohortPEM not requiredCross-Sectional

Cardiac function at rest and with exercise in the chronic fatigue syndrome.

Montague, T J, Marrie, T J, Klassen, G A et al.·Chest·1989

This study looked at heart function in 41 ME/CFS patients compared to healthy volunteers. While the hearts looked normal at rest, patients became exhausted during exercise much sooner than healthy people—their heart rates climbed more slowly and didn't reach the expected levels, even though their resting heart rhythms and structure were completely normal.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearObservational

Nondiscocytic erythrocytes in myalgic encephalomyelitis.

Simpson, L O·The New Zealand medical journal·1989

Researchers looked at red blood cells from 102 people with ME/CFS using a powerful microscope and compared them to healthy people and those with multiple sclerosis. They found that people with ME/CFS had fewer normal-shaped red blood cells and more cup-shaped red blood cells than the other groups. This suggests ME/CFS may have a physical cause that could potentially be detected through a blood test.

Biomarkers

E2 ModerateReviewPEM not requiredReview-Narrative

Fibromyalgia and its relation to chronic fatigue syndrome, viral illness and immune abnormalities.

Goldenberg, D L·The Journal of rheumatology. Supplement·1989

This study compared fibromyalgia and ME/CFS, two conditions that can feel similar to patients. Researchers found that most people with ME/CFS had tender points in their muscles similar to fibromyalgia patients. They also noted that both conditions may share similar underlying causes related to viral infections and how the immune system responds.

Immune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Psychiatric diagnoses in patients who have chronic fatigue syndrome.

Kruesi, M J, Dale, J, Straus, S E·The Journal of clinical psychiatry·1989

This study looked at 28 patients with ME/CFS to see how often they had been diagnosed with psychiatric conditions like depression. The researchers found that psychiatric diagnoses were common in this group. Importantly, when they reviewed medical records, they discovered that most of these psychiatric conditions had started before the ME/CFS illness began, not after.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Immunological abnormalities in the chronic fatigue syndrome.

Lloyd, A R, Wakefield, D, Boughton, C R et al.·The Medical journal of Australia·1989

This study compared the immune systems of 100 ME/CFS patients with 100 healthy people to see if immune problems might explain why ME/CFS causes such severe fatigue. Researchers found that ME/CFS patients had fewer immune cells and weaker immune responses than healthy people. These findings suggest that problems with how the immune system works may be involved in causing ME/CFS.

Immune System

E2 ModerateCohortPEM unclearObservational

Diagnosing myalgic encephalomyelitis.

Zala, J·The Practitioner·1989

This study looked at how doctors can diagnose ME/CFS, especially when standard blood tests don't show clear evidence of infection. Researchers compared patients who had lab evidence of infection with those who didn't, and discussed what doctors should look for to make a reliable diagnosis based on symptoms and clinical presentation alone.

Diagnostics

E2 ModerateCohortPEM unclearCross-Sectional

Coxsackie B viruses and myalgic encephalomyelitis.

Bell, E J, McCartney, R A, Riding, M H·Journal of the Royal Society of Medicine·1988

This study examined whether a common virus called Coxsackie B might be linked to ME/CFS. Researchers tested blood samples from ME/CFS patients and healthy people, and found that ME/CFS patients had higher rates of antibodies to this virus—suggesting they may have been infected with it. The findings suggest Coxsackie B viruses may play a role in this illness, though more research is needed to understand exactly how.

E2 ModerateCohortPEM not requiredObservational

"Chronic Epstein-Barr virus infection" syndrome and polymyalgia rheumatica.

Buchwald, D, Sullivan, J L, Leddy, S et al.·The Journal of rheumatology·1988

This study looked at 23 patients with polymyalgia rheumatica (PMR), a condition causing muscle pain and stiffness, and noticed many also experienced severe fatigue, sleep problems, and recurring sore throats—symptoms similar to ME/CFS. Even after treatment improved their muscle pain, these fatigue-related symptoms continued for months. However, blood tests showed their Epstein-Barr virus antibody levels were normal and similar to healthy people their age, suggesting the virus wasn't the primary cause.

Sleep

E2 ModerateCohortPEM unclearCase-Control

Cell-mediated immunity in patients with myalgic encephalomyelitis syndrome.

Murdoch, J C·The New Zealand medical journal·1988

This study tested immune system function in 33 ME/CFS patients compared to 33 healthy people of similar age and sex. Researchers used a skin test device called the multitest CMI to measure how well the immune system responded. They found that ME/CFS patients had weaker immune responses than healthy controls, suggesting their T-cells (a key type of immune cell) may not be working normally.

Immune System

E2 ModerateCohortPEM unclearCase-Control

Chronic fatigue syndrome and the diagnostic utility of antibody to Epstein-Barr virus early antigen.

Hellinger, W C, Smith, T F, Van Scoy, R E et al.·JAMA·1988

Researchers tested whether a specific blood marker for Epstein-Barr virus (EBV) could help diagnose chronic fatigue. They compared 30 people with chronic fatigue who had very high levels of this EBV marker to 30 healthy people without the marker. They found no meaningful differences between the two groups in their symptoms, physical exams, or other lab results, and this held true at follow-up visits. The study concluded that this particular EBV blood test is not useful for diagnosing or evaluating chronic fatigue.

E2 ModerateCohortPEM not requiredCase-Control

Sleep and symptoms in fibrositis syndrome after a febrile illness.

Moldofsky, H, Saskin, P, Lue, F A·The Journal of rheumatology·1988

This study looked at sleep patterns in people with fibromyalgia (a condition causing widespread pain and fatigue) who developed the condition after a fever, compared to people with fibromyalgia without a clear trigger and healthy volunteers. All fibromyalgia patients showed abnormal brain wave patterns during sleep that prevented their sleep from being truly restful, and they experienced similar muscle pain and tender points. This suggests that post-illness fibromyalgia shares the same sleep problems as other forms of fibromyalgia.

Sleep

E2 ModerateBehavioralPEM not requiredObservational

The frequency of the chronic fatigue syndrome in patients with symptoms of persistent fatigue.

Manu, P, Lane, T J, Matthews, D A·Annals of internal medicine·1988

This study looked at 135 people with severe fatigue lasting at least 6 months to see how many actually had ME/CFS. The researchers found that only 6 patients (about 4%) met the criteria for ME/CFS, while most of the others had psychiatric conditions like depression or anxiety that were causing their fatigue. This suggests that ME/CFS is quite rare among people presenting with fatigue symptoms.

Diagnostics

E2 ModerateBehavioralPEM not requiredCross-Sectional

Depression in patients with neuromyasthenia (benign myalgic encephalomyelitis).

Taerk, G S, Toner, B B, Salit, I E et al.·International journal of psychiatry in medicine·1987

This study looked at depression in people with ME/CFS (then called neuromyasthenia) using structured interviews and psychological tests. Researchers found that 67% of ME/CFS patients met criteria for major depression, and notably, half of these patients had depression before they developed ME/CFS. The study suggests that some people with ME/CFS may be psychologically vulnerable to developing the condition after a viral illness.

E2 ModerateCohortPEM not requiredObservational

Frequency of 'chronic active Epstein-Barr virus infection' in a general medical practice.

Buchwald, D, Sullivan, J L, Komaroff, A L·JAMA·1987

Researchers studied 500 patients visiting a general doctor's office and found that about 21% experienced severe, ongoing fatigue similar to ME/CFS, often with symptoms like sore throat, muscle pain, and headaches lasting months or years. While some blood tests showed higher levels of Epstein-Barr virus (EBV) antibodies in these patients compared to healthy people, the differences were not strong enough to prove EBV caused their fatigue. The study warns that current EBV blood tests should be interpreted carefully and may not reliably diagnose the cause of chronic fatigue.

E2 ModerateCohortPEM unclearCross-Sectional

Blood rheology and myalgic encephalomyelitis: a pilot study.

Simpson, L O, Shand, B I, Olds, R J·Pathology·1986

This study examined whether blood flows differently in people with ME/CFS compared to healthy people. Researchers tested blood samples and found that in the early stages of ME/CFS, blood may not flow as easily through tiny blood vessels, which could reduce oxygen delivery to tissues. However, in long-term ME/CFS, these blood flow problems were not observed.

E2 ModerateCohortPEM unclearObservational

A study of Coxsackie B virus infections, 1972-1983.

Bell, E J, McCartney, R A·The Journal of hygiene·1984

Over 12 years, researchers tested blood samples from patients with various illnesses to see if they had been infected with Coxsackie B virus. They found that people with ME/CFS were more likely to have evidence of this virus infection (41% of well-documented ME patients) compared to healthy people (4%). This suggests Coxsackie B virus might play a role in some ME/CFS cases, though the study cannot prove the virus causes the illness.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Personality and medical perception in benign myalgic encephalomyelitis.

May, P G, Donnan, S P, Ashton, J R et al.·Lancet (London, England)·1980

This 1980 study looked at girls at a school where some developed ME/CFS-like illness during an outbreak. Researchers tested all the girls—both sick and healthy—and found that the sick girls tended to be more emotionally sensitive or anxious than the healthy ones. However, viruses weren't consistently found, and the study suggested that doctors may have sometimes labeled different conditions with the same name, making it harder to understand what was really happening.

E2 ModerateCohortPEM unclearObservational

[Epidemic myalgic encephalomyelitis].

Walther, H·Schweizerische Rundschau fur Medizin Praxis = Revue suisse de medecine Praxis·1972

This 1972 case study describes an outbreak of myalgic encephalomyelitis (ME), a serious illness causing muscle pain, brain inflammation, and extreme fatigue. The author documented patients who experienced this epidemic, helping early medical professionals recognize and understand the disease pattern.

Diagnostics

E3 PreliminaryReviewPEM not requiredReview-Narrative

Pathophysiological mechanisms of fatigue and multidisciplinary management strategies (Review).

Zhou, Hong, Yu, Wenwen, Lei, Jiaming et al.·Experimental and therapeutic medicine·2026

This review examines why people feel extreme fatigue and how doctors can better manage it. The authors explain that fatigue involves problems with how the body makes energy, stress chemicals in the body, and the immune system. They discuss how new technologies and teamwork between different medical specialists—plus telemedicine—can help patients with chronic fatigue syndrome and other conditions feel better.

Energy Metabolism

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Asthenic symptoms in a rural family practice. Epidemiologic characteristics and a proposed classification.

Cardiac function at rest and with exercise in the chronic fatigue syndrome.

Nondiscocytic erythrocytes in myalgic encephalomyelitis.

Fibromyalgia and its relation to chronic fatigue syndrome, viral illness and immune abnormalities.

Psychiatric diagnoses in patients who have chronic fatigue syndrome.

Immunological abnormalities in the chronic fatigue syndrome.

Diagnosing myalgic encephalomyelitis.

Coxsackie B viruses and myalgic encephalomyelitis.

"Chronic Epstein-Barr virus infection" syndrome and polymyalgia rheumatica.

Cell-mediated immunity in patients with myalgic encephalomyelitis syndrome.

Chronic fatigue syndrome and the diagnostic utility of antibody to Epstein-Barr virus early antigen.

Sleep and symptoms in fibrositis syndrome after a febrile illness.

The frequency of the chronic fatigue syndrome in patients with symptoms of persistent fatigue.

Depression in patients with neuromyasthenia (benign myalgic encephalomyelitis).

Frequency of 'chronic active Epstein-Barr virus infection' in a general medical practice.

Blood rheology and myalgic encephalomyelitis: a pilot study.

A study of Coxsackie B virus infections, 1972-1983.

Personality and medical perception in benign myalgic encephalomyelitis.

[Epidemic myalgic encephalomyelitis].

Pathophysiological mechanisms of fatigue and multidisciplinary management strategies (Review).

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