Evidence browser

Chronic fatigue syndrome: clinical condition associated with immune activation.

Landay, A L, Jessop, C, Lennette, E T et al.·Lancet (London, England)·1991

Researchers used specialized tests to examine immune cells from 147 people with ME/CFS and compared them to healthy people. They found that people with ME/CFS had lower levels of certain immune cells (CD8 suppressor cells) and higher levels of immune activation markers on other immune cells. These differences were not seen in healthy people, contacts of patients, or people with other illnesses, suggesting that immune system activation may be involved in ME/CFS.

E2 ModerateCohortPEM unclearCross-Sectional

Primary fibromyalgia and the chronic fatigue syndrome.

Wysenbeek, A J, Shapira, Y, Leibovici, L·Rheumatology international·1991

This study looked at 33 people with fibromyalgia to see how many also had ME/CFS. While most reported significant fatigue, only about one in five people met the full criteria for ME/CFS. The researchers found that symptoms like swollen lymph nodes and fever were rare in fibromyalgia patients but might be more common in ME/CFS, suggesting these could help doctors tell the two conditions apart.

Diagnostics

E2 ModerateBehavioralPEM not requiredCross-Sectional

Biopsychosocial aspects of chronic fatigue syndrome (myalgic encephalomyelitis).

Yeomans, J D, Conway, S P·The Journal of infection·1991

This study looked at 15 people with chronic fatigue referred by their doctors. Researchers found that while most patients reported feeling emotionally distressed, only a few actually had a diagnosed depression disorder. Many patients struggled with work and daily activities. Tests for infections, blood abnormalities, and immune problems came back normal, suggesting ME/CFS is not simply caused by one medical problem.

E2 ModerateCohortPEM unclearObservational

No association of HLA class II antigens in chronic fatigue syndrome.

Middleton, D, Savage, D A, Smith, D G·Disease markers·1991

This study examined whether certain immune system markers called HLA class II antigens were associated with ME/CFS. Researchers compared these markers in people with ME/CFS and healthy controls. The study found no link between these particular immune markers and ME/CFS, suggesting that HLA class II antigens are not a defining feature of the condition.

E2 ModerateCohortPEM unclearObservational

Search for an association between Epstein-Barr virus infection and the chronic fatigue syndrome.

Joncas, J H·Canada diseases weekly report = Rapport hebdomadaire des maladies au Canada·1991

This study looked at whether Epstein-Barr virus (EBV), a common virus that causes mononucleosis, might be connected to ME/CFS. Researchers compared people with ME/CFS to other groups to see if they had different levels of EBV infection or antibodies. This was one of the early investigations into potential viral causes of ME/CFS.

E2 ModerateCohortPEM not requiredObservational

Chronic fatigue syndrome in Minnesota.

Peterson, P K, Schenck, C H, Sherman, R·Minnesota medicine·1991

This study looked at 135 people in Minnesota with ME/CFS to understand who gets the disease and how it develops. Most patients reported that their illness started suddenly with what looked like an infection, and fatigue was their worst symptom. When researchers checked in with some patients a year later, none had fully recovered, though about 40% felt somewhat better.

E2 ModerateBehavioralPEM not requiredCross-Sectional

A comparative psychiatric assessment of patients with chronic fatigue syndrome and muscle disease.

Wood, G C, Bentall, R P, Göpfert, M et al.·Psychological medicine·1991

This study compared the mental health of 34 patients with ME/CFS to 24 patients with muscle disease. Researchers found that people with ME/CFS were more likely to have psychiatric conditions like depression or anxiety—about 41% had clear psychiatric diagnoses and another 27% had partial ones. In contrast, only about 17% of muscle disease patients had psychiatric conditions. This suggests ME/CFS patients face a higher risk of developing psychiatric issues, though the study doesn't explain why.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Psychiatric illness in patients with chronic fatigue and those with rheumatoid arthritis.

Katon, W J, Buchwald, D S, Simon, G E et al.·Journal of general internal medicine·1991

This study compared people with chronic fatigue to people with rheumatoid arthritis to understand psychiatric differences between the groups. Researchers found that people with chronic fatigue had higher rates of depression and other mental health conditions than people with rheumatoid arthritis. Interestingly, when they looked specifically at patients who met strict CDC criteria for CFS, these patients were not noticeably different from those with chronic fatigue who didn't meet the criteria.

Diagnostics

Risk factors associated with chronic fatigue syndrome in a cluster of pediatric cases.

Bell, K M, Cookfair, D, Bell, D S et al.·Reviews of infectious diseases·1991

After seven children in a farming community developed ME/CFS, researchers asked all students in the school district about their symptoms and possible causes. They found 21 students with CFS symptoms and compared them to matched healthy students. Three factors stood out as being strongly linked to CFS: having family members with CFS symptoms, recently drinking raw milk, and having a history of allergies or asthma.

Chronic fatigue syndrome: I. Epstein-Barr virus immune response and molecular epidemiology.

Jones, J F, Streib, J, Baker, S et al.·Journal of medical virology·1991

This study looked at how the immune system responds to Epstein-Barr virus (EBV) in ME/CFS patients compared to healthy people who have been infected with EBV. Researchers found that immune cells from ME/CFS patients were much more likely to grow uncontrollably in the lab (30% vs 8%), and patients showed more signs of active viral infection in their blood. These findings suggest that some ME/CFS patients may have difficulty controlling EBV reactivation.

General practitioners' experience of the chronic fatigue syndrome.

Ho-Yen, D O, McNamara, I·The British journal of general practice : the journal of the Royal College of General Practitioners·1991

Researchers surveyed doctors in Scotland to understand how common ME/CFS is and how they view the condition. Most doctors (71%) believed ME/CFS is real, though some were uncertain. The study found about 1-2 people per 1,000 patients have ME/CFS, with more women affected than men, and it particularly affects people in their 30s and 40s.

A comprehensive immunological analysis in chronic fatigue syndrome.

Gupta, S, Vayuvegula, B·Scandinavian journal of immunology·1991

Researchers compared immune system cells and antibodies in 20 ME/CFS patients and 20 healthy people to see if there were differences. They found that ME/CFS patients had fewer natural killer cells (immune cells that fight infections), some changes in how their immune cells communicate with each other, and weaker responses to certain types of immune challenges. These findings suggest the immune system works differently in ME/CFS.

E2 ModerateReviewPEM not requiredReview-Narrative

Frequent double infection with Epstein-Barr virus and human herpesvirus-6 in patients with acute infectious mononucleosis.

Bertram, G, Dreiner, N, Krueger, G R et al.·In vivo (Athens, Greece)·1991

This study looked at 215 patients with infectious mononucleosis to see which viruses were causing their illness. Researchers found that most patients had Epstein-Barr virus (EBV), but many also had human herpesvirus-6 (HHV-6) at the same time. About 40% of patients had active infection with both viruses, and some had a third virus (CMV) as well. Patients were followed for two years to track changes in their virus levels.

Chronic fatigue syndrome in northern Nevada.

Daugherty, S A, Henry, B E, Peterson, D L et al.·Reviews of infectious diseases·1991

Between 1984 and 1988, doctors in northern Nevada identified over 400 patients with ME/CFS and found a common pattern of symptoms and lab abnormalities in those who were moderately to severely ill. The pattern included extreme fatigue, sore throats, memory and concentration problems, muscle pain, and specific changes in immune system markers and brain imaging. Some patients experienced more serious problems like seizures or cognitive decline.

E2 ModerateReviewPEM unclearReview-Narrative

Antibodies to Epstein-Barr virus in patients with chronic fatigue.

Matthews, D A, Lane, T J, Manu, P·Southern medical journal·1991

This study tested whether Epstein-Barr virus (EBV) antibodies in the blood can help identify ME/CFS patients. Researchers compared 35 fatigued patients with signs of chronic EBV infection to 35 matched fatigued patients without these signs. They found very few differences between the groups, suggesting that EBV antibody testing is not particularly useful for diagnosing or understanding chronic fatigue.

Symptoms and signs of chronic fatigue syndrome.

Komaroff, A L, Buchwald, D·Reviews of infectious diseases·1991

This review summarizes what doctors have learned about chronic fatigue syndrome (ME/CFS) by studying approximately 510 patients. The hallmark features include a sudden illness-like onset, long-lasting exhaustion that severely limits daily activities, and a unique symptom called postexertional malaise—where patients feel much worse after physical or mental activity. Many patients also experience fever, sore throat, swollen lymph nodes, muscle pain, sleep problems, and difficulty concentrating.

Post-Exertional Malaise

E2 ModerateBehavioralPEM not requiredCross-Sectional

Depression and somatization in the chronic fatigue syndrome.

Lane, T J, Manu, P, Matthews, D A·The American journal of medicine·1991

This study looked at 60 patients diagnosed with chronic fatigue syndrome (CFS) to see how often they had depression or other psychiatric conditions. Researchers found that most CFS patients (78%) had some kind of mental health disorder, similar to a control group of fatigued people without CFS. However, CFS patients were more likely to have somatization disorder (believing physical symptoms have a physical cause) and were more likely to attribute their illness to a physical problem rather than psychological stress.

E2 ModerateCohortPEM unclearCross-Sectional

Chronic fatigue syndrome: lack of association with hepatitis C virus infection.

Dale, J K, Di Bisceglie, A M, Hoofnagle, J H et al.·Journal of medical virology·1991

Researchers tested whether hepatitis C virus (HCV), a virus that affects the liver, might be a cause of ME/CFS. They compared blood tests from 36 ME/CFS patients and 14 healthy controls. They found that only one ME/CFS patient showed signs of past HCV infection, while none of the healthy people did. This suggests that hepatitis C is not a common cause of ME/CFS.

Immune responsiveness in chronic fatigue syndrome.

Milton, J D, Clements, G B, Edwards, R H·Postgraduate medical journal·1991

This 1991 study tested whether ME/CFS was caused by a persistent viral infection or a weakened immune response to viruses. Researchers compared immune markers and virus-fighting abilities in ME/CFS patients, healthy controls, and people with muscular dystrophy. They found no significant differences between groups, suggesting that standard viral infection or immune dysfunction wasn't the primary cause of ME/CFS.