Evidence browser

Sleep disturbance in chronic fatigue syndrome.

Krupp, L B, Jandorf, L, Coyle, P K et al.·Journal of psychosomatic research·1993

This study looked at sleep problems in 72 people with ME/CFS, comparing them to people with multiple sclerosis and healthy volunteers. People with ME/CFS reported much worse sleep and fatigue than the other groups. When researchers used sleep monitoring equipment on some ME/CFS patients, they found that over half had treatable sleep disorders like sleep apnea or periodic leg movements during sleep.

Sleep

Investigation of retroviral involvement in chronic fatigue syndrome.

Folks, T M, Heneine, W, Khan, A et al.·Ciba Foundation symposium·1993

Researchers tested whether certain viruses called retroviruses might be a biological marker that could help diagnose ME/CFS. They looked for five different retroviruses in people with ME/CFS and compared them to healthy controls. None of these viruses were found in either group, meaning they cannot be used to identify who has ME/CFS.

Biomarkers

Inability of retroviral tests to identify persons with chronic fatigue syndrome, 1992.

Centers for Disease Control and Prevention (CDC)·MMWR. Morbidity and mortality weekly report·1993

In the early 1990s, some laboratories were offering blood tests to check if people with ME/CFS had been infected with certain viruses called retroviruses. This CDC study tested whether three of these commercial tests could actually tell the difference between people with ME/CFS and healthy people. The researchers found that these tests could not reliably distinguish between the two groups, meaning the tests were not accurate for identifying ME/CFS.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Repetitively negative changing T waves at 24-h electrocardiographic monitors in patients with the chronic fatigue syndrome. Left ventricular dysfunction in a cohort.

Lerner, A M, Lawrie, C, Dworkin, H S·Chest·1993

This study looked at heart activity recorded over 24 hours in ME/CFS patients compared to others. All 24 ME/CFS patients showed unusual patterns on their heart monitors (abnormal T waves), compared to only 22% of people without ME/CFS. Further testing found that 8 out of 60 ME/CFS patients had mild heart pumping problems that only showed up during exercise, even though their resting heart function appeared normal. The researchers suggest ME/CFS fatigue might be related to the heart not working well during normal daily activities.

Post-Exertional Malaise

A comparison of neuropsychiatric characteristics in chronic fatigue syndrome, multiple sclerosis, and major depression.

Pepper, C M, Krupp, L B, Friedberg, F et al.·The Journal of neuropsychiatry and clinical neurosciences·1993

This study compared the emotional and psychological characteristics of people with ME/CFS to those with multiple sclerosis and major depression. The researchers found that people with ME/CFS experienced depression, but overall had fewer psychiatric and personality-related issues compared to those with major depression alone. Interestingly, ME/CFS patients were more likely to develop depression after their illness began, compared to MS patients.

Prevalence of chronic fatigue syndrome-related symptoms among nurses.

Jason, L A, Taylor, S L, Johnson, S et al.·Evaluation & the health professions·1993

This study looked at how common ME/CFS-related symptoms are among nurses. Researchers surveyed a group of nurses and found that when using different definitions of the illness, more nurses showed signs of ME/CFS than had been found in previous studies of the general population. This was the first study to specifically examine ME/CFS in healthcare workers.

Abnormalities of sleep in patients with the chronic fatigue syndrome.

Morriss, R, Sharpe, M, Sharpley, A L et al.·BMJ (Clinical research ed.)·1993

This study compared sleep patterns between 12 people with ME/CFS and 12 healthy volunteers using both sleep diaries and objective monitoring devices. People with ME/CFS spent more time in bed but slept less efficiently, woke up more after falling asleep, and were more likely to have sleep disorders. The researchers concluded that sleep problems are common in ME/CFS and may contribute to daytime fatigue.

Assessment of a retrovirus sequence and other possible risk factors for the chronic fatigue syndrome in adults.

Khan, A S, Heneine, W M, Chapman, L E et al.·Annals of internal medicine·1993

Researchers tested whether a virus called HTLV-II might be a cause of ME/CFS by comparing blood samples from 21 people with CFS to 21 healthy controls. They found no trace of the HTLV-II virus in any of the participants, and found no differences between the two groups in exposure to activities that spread viruses. This study argues against the idea that HTLV-II is linked to ME/CFS.

A brief mental fatigue questionnaire.

Bentall, R P, Wood, G C, Marrinan, T et al.·The British journal of clinical psychology·1993

Researchers created a short questionnaire to measure mental tiredness and tested it in people with ME/CFS, depression, recovered ME/CFS, muscle disease, and healthy people. The questionnaire worked well at identifying mental fatigue, but it could not tell the difference between people with ME/CFS and people with depression—both groups reported similar types and amounts of mental tiredness.

Cognitive Impairment

Human herpesvirus 6 and chronic fatigue syndrome.

Eymard, D, Lebel, F, Miller, M et al.·The Canadian journal of infectious diseases = Journal canadien des maladies infectieuses·1993

This study compared antibody levels against human herpesvirus 6 (HHV-6) in two groups: people with ME/CFS and people with chronic fatigue who didn't meet the official ME/CFS diagnosis. Researchers found that people with ME/CFS had significantly higher antibody levels against HHV-6, suggesting the virus might play a role in the condition. The study also found that sore throat, headache, and recurrent fatigue were more common in the ME/CFS group.

Immune System

Serum folate and chronic fatigue syndrome.

Jacobson, W, Saich, T, Borysiewicz, L K et al.·Neurology·1993

Researchers measured folic acid levels in the blood of 60 ME/CFS patients and found that about half had lower-than-normal amounts. This suggests that some people with ME/CFS may not have enough folic acid in their body, which is a B vitamin important for many body functions.

Japanese patients with chronic fatigue syndrome are negative for known retrovirus infections.

Honda, M, Kitamura, K, Nakasone, T et al.·Microbiology and immunology·1993

This study tested 30 Japanese patients with ME/CFS to see if they had been infected with certain viruses called retroviruses, which some researchers thought might cause the illness. Using multiple testing methods, the researchers found that none of the patients had these viral infections. This suggests that these particular known viruses are not responsible for causing ME/CFS in this Japanese patient population.

Prevalence of fatigue and chronic fatigue syndrome in a primary care practice.

Bates, D W, Schmitt, W, Buchwald, D et al.·Archives of internal medicine·1993

This study looked at how common severe, long-lasting fatigue is in a primary care doctor's office and how often it is ME/CFS. Researchers found that while about 27% of patients had long-term fatigue affecting their daily life, most could be explained by other medical or mental health conditions. Only about 0.3% to 1% of patients actually had ME/CFS, depending on which diagnostic criteria were used.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue and chronic fatigue syndrome: clinical epidemiology and aetiological classification.

Manu, P, Lane, T J, Matthews, D A·Ciba Foundation symposium·1993

This study looked at 405 patients who came to a hospital complaining of chronic fatigue and tried to figure out what was causing it. Doctors found that most patients had psychiatric conditions like depression or anxiety rather than physical diseases. About 30% of patients met the definition for ME/CFS, and these patients were more likely to attribute their illness to a viral infection than other fatigued patients.

Cell-mediated immunity in patients with chronic fatigue syndrome, healthy control subjects and patients with major depression.

Lloyd, A, Hickie, I, Hickie, C et al.·Clinical and experimental immunology·1992

This study compared immune system function in patients with ME/CFS, people with depression, and healthy individuals. Researchers found that ME/CFS patients had weaker immune responses than both groups, suggesting their immune problems are distinct from depression-related immune changes. This indicates that ME/CFS involves direct immune system dysfunction rather than these problems simply being caused by depression.

Immune System

E2 ModerateCohortPEM not requiredObservational

Assessment of regional cerebral perfusion by 99Tcm-HMPAO SPECT in chronic fatigue syndrome.

Ichise, M, Salit, I E, Abbey, S E et al.·Nuclear medicine communications·1992

This study used a special brain imaging technique called SPECT to measure blood flow in different regions of the brain in ME/CFS patients and healthy controls. Researchers found that most ME/CFS patients (80%) had reduced blood flow in several brain areas compared to healthy people, particularly in the front, side, and back regions of the brain. This provides the first objective evidence that ME/CFS may involve changes in how blood flows to the brain.

Clinical, epidemiologic, and virologic studies in four clusters of the chronic fatigue syndrome.

Levine, P H, Jacobson, S, Pocinki, A G et al.·Archives of internal medicine·1992

Researchers studied four different outbreaks of ME/CFS in the Nevada-California region over 3 years, following patients through interviews and blood tests to look for viral causes. They found that almost all patients recovered and returned to their normal activities within the 3-year period. The viruses they tested for—including Epstein-Barr virus and others—were not responsible for the illness, though one outbreak may have been triggered by a parasite called giardia.

Ureaplasma urealyticum and Mycoplasma hominis in women with systemic lupus erythematosus.

Ginsburg, K S, Kundsin, R B, Walter, C W et al.·Arthritis and rheumatism·1992

This study looked for a type of bacteria called mycoplasma in urine samples from women with two different conditions: systemic lupus erythematosus (SLE, an autoimmune disease) and ME/CFS (chronic fatigue syndrome). They found that mycoplasma was much more common in the SLE group (63%) than in the ME/CFS group (4.5%), suggesting these conditions may have different underlying causes.

Comorbidity of fibromyalgia with medical and psychiatric disorders.

Hudson, J I, Goldenberg, D L, Pope, H G et al.·The American journal of medicine·1992

This study looked at women diagnosed with fibromyalgia to see what other health conditions they commonly experience. The researchers found that fibromyalgia often occurs together with migraines, irritable bowel syndrome, chronic fatigue syndrome, depression, and panic disorder. This pattern suggests these conditions might share a common underlying biological cause.