ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

3601–3620 of 6,161 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Prevalence of chronic fatigue syndrome in Italian patients with persistent fatigue.

Conti, F, Priori, R, De Petrillo, G et al.·Annali italiani di medicina interna : organo ufficiale della Societa italiana di medicina interna·1994

Researchers in Rome studied 63 patients with persistent fatigue lasting at least 6 months to see how many actually had ME/CFS. They found that only 6 patients (about 10%) met the official diagnostic criteria for ME/CFS, while 37 patients (59%) had other medical conditions explaining their fatigue, such as infections or other illnesses. This suggests that ME/CFS is relatively uncommon as a cause of severe fatigue compared to other treatable conditions.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

A comparison of case definitions of chronic fatigue syndrome.

Bates, D W, Buchwald, D, Lee, J et al.·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1994

This study tested whether three different sets of diagnostic criteria for ME/CFS identified the same patients. Researchers looked at 805 patients at two clinics and found that about 55-61% met each of the three definitions, though different patients sometimes qualified under different criteria. The study suggests that using broader, more flexible definitions might better capture people with ME/CFS.

Diagnostics

E2 ModerateCohortPEM unclearCross-Sectional

Chronic fatigue syndrome and a disorder resembling Sjögren's syndrome: preliminary report.

Calabrese, L H, Davis, M E, Wilke, W S·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1994

This study looked at whether people diagnosed with ME/CFS might actually have a condition similar to Sjögren's syndrome, a disease that causes dry mouth and eyes along with immune system problems. Researchers found that many patients in their ME/CFS clinic had signs of this Sjögren's-like illness, including abnormal tests and certain antibodies in their blood. The study suggests these two conditions may overlap more often than doctors realize.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Immunological abnormalities in patients with chronic fatigue syndrome.

Tirelli, U, Marotta, G, Improta, S et al.·Scandinavian journal of immunology·1994

Researchers studied 265 ME/CFS patients and found unusual patterns in their immune cells compared to healthy people. They discovered that certain types of white blood cells called natural killer (NK) cells and B cells were abnormally increased, and these cells showed signs of being overly activated. These immune abnormalities appeared consistent with what other researchers had found in different countries.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Hyperventilation and chronic fatigue syndrome.

Saisch, S G, Deale, A, Gardner, W N et al.·The Quarterly journal of medicine·1994

Researchers tested whether people with ME/CFS tend to overbreathe (hyperventilate), which could contribute to their fatigue. They measured breathing patterns in 31 patients at rest, during exercise, and after voluntary heavy breathing. Most patients did not show signs of hyperventilation, and those who did usually had other explanations like asthma or panic disorder.

E2 ModerateReviewPEM unclearReview-Narrative

A comparative review of systemic and neurological symptomatology in 12 outbreaks collectively described as chronic fatigue syndrome, epidemic neuromyasthenia, and myalgic encephalomyelitis.

Briggs, N C, Levine, P H·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1994

This study reviewed 12 documented outbreaks of ME/CFS-like illness from 1934 to the 1980s to understand how symptoms varied between them. While all outbreaks shared common features like extreme fatigue, muscle pain, and headaches, the neurological symptoms (affecting the nervous system) differed significantly. The researchers found that older outbreaks (1930s-1950s) showed more severe objective nerve damage, while later outbreaks (1960s-1980s) had milder neurological findings, possibly because doctors weren't looking for these symptoms as carefully.

E2 ModerateCohortPEM not requiredCross-Sectional

Sympathetic overactivity in subjects complaining of unexplained fatigue.

Pagani, M, Lucini, D, Mela, G S et al.·Clinical science (London, England : 1979)·1994

This study examined how the nervous system controls heart rate in people with unexplained fatigue compared to healthy people. Using heart rate recordings, researchers found that fatigue patients showed an imbalance in their autonomic nervous system—specifically, the part that triggers the "fight or flight" response was overactive while the calming part was underactive, even at rest.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Seasonal symptom variation in patients with chronic fatigue: comparison with major mood disorders.

Zubieta, J K, Engleberg, N C, Yargiç, L I et al.·Journal of psychiatric research·1994

This study compared how much ME/CFS and chronic fatigue symptoms vary by season in different groups of patients. The researchers found that people with ME/CFS and chronic fatigue had much less seasonal symptom variation than people with seasonal depression or other mood disorders. Even when fatigue patients did experience some seasonal changes, they didn't find it particularly distressing.

E2 ModerateCohortPEM not requiredCross-Sectional

[Viral infection and fibromyalgia].

Branco, J C, Tavares, V, Abreu, I et al.·Acta medica portuguesa·1994

This study looked at whether a common virus called parvovirus B19 might be responsible for fibromyalgia, a condition similar to ME/CFS that causes widespread pain and fatigue. Researchers compared blood antibodies (which show past infection) in 52 fibromyalgia patients versus 39 healthy people. They found slightly higher rates of past parvovirus infection in fibromyalgia patients, but the difference was too small to be meaningful, so they concluded the virus is probably not the cause of fibromyalgia.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

High titers of anti-Epstein-Barr virus DNA polymerase are found in patients with severe fatiguing illness.

Natelson, B H, Ye, N, Moul, D E et al.·Journal of medical virology·1994

This study looked for specific antibodies (proteins the immune system makes) against Epstein-Barr virus (EBV) in people with ME/CFS compared to healthy people. Researchers found that abnormal levels of these antibodies were twice as common in ME/CFS patients, and the effect was even stronger in sicker patients. This suggests these antibodies might help doctors identify which ME/CFS patients have more severe illness.

Immune System

E2 ModerateCohortPEM not requiredCase-Control

Simultaneous measurement of antibodies to Epstein-Barr virus, human herpesvirus 6, herpes simplex virus types 1 and 2, and 14 enteroviruses in chronic fatigue syndrome: is there evidence of activation of a nonspecific polyclonal immune response?

Manian, F A·Clinical infectious diseases : an official publication of the Infectious Diseases Society of America·1994

This study looked at whether people with ME/CFS have higher levels of antibodies (immune proteins that fight viruses) to multiple different viruses compared to healthy people. Researchers tested blood samples from 20 ME/CFS patients and 20 healthy controls for antibodies to five different viruses. They found that most ME/CFS patients had elevated antibodies to at least one virus, but the pattern didn't suggest a generalized immune overreaction affecting all viruses equally.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Detection of intracranial abnormalities in patients with chronic fatigue syndrome: comparison of MR imaging and SPECT.

Schwartz, R B, Garada, B M, Komaroff, A L et al.·AJR. American journal of roentgenology·1994

Researchers used two different brain imaging techniques—MRI and SPECT—to look for abnormalities in the brains of ME/CFS patients. They found that SPECT scans detected significantly more brain abnormalities in ME/CFS patients compared to healthy controls, while MRI scans showed fewer differences. Importantly, SPECT abnormalities appeared to change with clinical status, suggesting they might be useful for tracking disease progression.

E2 ModerateBehavioralPEM not requiredLongitudinal

Longitudinal study of outcome of chronic fatigue syndrome.

Wilson, A, Hickie, I, Lloyd, A et al.·BMJ (Clinical research ed.)·1994

This study followed 103 ME/CFS patients for about 3 years to see who got better and why. Most patients improved somewhat over time, but only a small number felt completely well. The researchers found that how patients thought about their illness and coped with it mattered more for recovery than immune system tests or how old they were when they got sick.

E2 ModerateCohortPEM not requiredCross-Sectional

Single fibre EMG studies in chronic fatigue syndrome: a reappraisal.

Roberts, L, Byrne, E·Journal of neurology, neurosurgery, and psychiatry·1994

Researchers used a specialized test called single fibre EMG to examine how well the muscles and nerves work together in people with ME/CFS. They tested 30 patients with ME/CFS and compared them to 30 healthy controls. While they found some minor differences, the differences were so small that the researchers concluded problems with nerve-muscle communication are unlikely to be a main cause of ME/CFS.

E2 ModerateCohortPEM not requiredObservational

Low grade pyrexia: is it chronic fatigue syndrome?

Anand, A C, Kumar, R, Rao, M K et al.·The Journal of the Association of Physicians of India·1994

This study followed 87 patients who had a persistent low-grade fever (99-101°F) along with fatigue, muscle pain, and joint pain. Doctors ran many tests looking for infections, autoimmune diseases, or cancer, but found nothing abnormal. Most patients gradually improved over time, with about half becoming symptom-free within three years. The researchers suggest this condition might be related to ME/CFS.

E2 ModerateCohortPEM not requiredCross-Sectional

Fatigue secondary to chronic illness: postpolio syndrome, chronic fatigue syndrome, and multiple sclerosis.

Packer, T L, Sauriol, A, Brouwer, B·Archives of physical medicine and rehabilitation·1994

This study compared fatigue in people with three different chronic illnesses: postpolio syndrome, ME/CFS, and multiple sclerosis. Researchers found that people with all three conditions experienced much higher levels of fatigue than healthy people, and those with ME/CFS and MS also had greater difficulty doing everyday activities. The study highlights how serious and disabling fatigue can be across these different conditions.

E2 ModerateCohortPEM not requiredCross-Sectional

[Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes].

Hilgers, A, Frank, J·Wiener medizinische Wochenschrift (1946)·1994

This study examined 375 patients with ME/CFS to understand what goes wrong with their immune systems and which infections might be involved. Researchers found that most patients had problems with immune cell function, signs of past viral infections (especially Epstein-Barr virus), and imbalances in immune chemicals. The study suggests ME/CFS may be connected to autoimmune problems and multiple infections.

Immune System

E2 ModerateBehavioralPEM not requiredCross-Sectional

Dimensional assessment of chronic fatigue syndrome.

Vercoulen, J H, Swanink, C M, Fennis, J F et al.·Journal of psychosomatic research·1994

This study asked 298 people with ME/CFS to fill out detailed questionnaires about how the illness affected them. Researchers found that ME/CFS affects people in nine different ways: mood and emotional health, ability to do daily activities, sleep quality, physical avoidance, thinking and memory problems, beliefs about what caused their illness, relationships and social life, confidence in their own abilities, and overall life satisfaction. Understanding these separate aspects could help doctors better assess and treat ME/CFS in individual patients.

SleepCognitive Impairment

E2 ModerateCohortPEM unclearCross-Sectional

Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities.

Buchwald, D, Garrity, D·Archives of internal medicine·1994

This study compared 90 patients with three conditions that cause fatigue and other symptoms: ME/CFS, fibromyalgia, and multiple chemical sensitivities. The researchers found that these three conditions are very similar in many ways—patients often report overlapping symptoms, and many people meet the criteria for more than one condition. All three groups used a lot of healthcare services, visiting doctors about 22-40 times per year on average.

Diagnostics

E2 ModerateCohortPEM not requiredCase-Control

Cognitive functioning and depression in patients with chronic fatigue syndrome and multiple sclerosis.

Krupp, L B, Sliwinski, M, Masur, D M et al.·Archives of neurology·1994

This study compared thinking and memory problems in people with ME/CFS, multiple sclerosis (MS), and healthy controls. People with ME/CFS showed some cognitive difficulties, particularly in processing speed and memory tasks, and had higher rates of depression. However, their cognitive problems were less widespread than those seen in MS patients, and some thinking difficulties in ME/CFS appeared linked to depression rather than the illness itself.

Cognitive Impairment

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Prevalence of chronic fatigue syndrome in Italian patients with persistent fatigue.

A comparison of case definitions of chronic fatigue syndrome.

Chronic fatigue syndrome and a disorder resembling Sjögren's syndrome: preliminary report.

Immunological abnormalities in patients with chronic fatigue syndrome.

Hyperventilation and chronic fatigue syndrome.

A comparative review of systemic and neurological symptomatology in 12 outbreaks collectively described as chronic fatigue syndrome, epidemic neuromyasthenia, and myalgic encephalomyelitis.

Sympathetic overactivity in subjects complaining of unexplained fatigue.

Seasonal symptom variation in patients with chronic fatigue: comparison with major mood disorders.

[Viral infection and fibromyalgia].

High titers of anti-Epstein-Barr virus DNA polymerase are found in patients with severe fatiguing illness.

Simultaneous measurement of antibodies to Epstein-Barr virus, human herpesvirus 6, herpes simplex virus types 1 and 2, and 14 enteroviruses in chronic fatigue syndrome: is there evidence of activation of a nonspecific polyclonal immune response?

Detection of intracranial abnormalities in patients with chronic fatigue syndrome: comparison of MR imaging and SPECT.

Longitudinal study of outcome of chronic fatigue syndrome.

Single fibre EMG studies in chronic fatigue syndrome: a reappraisal.

Low grade pyrexia: is it chronic fatigue syndrome?

Fatigue secondary to chronic illness: postpolio syndrome, chronic fatigue syndrome, and multiple sclerosis.

[Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes].

Dimensional assessment of chronic fatigue syndrome.

Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities.

Cognitive functioning and depression in patients with chronic fatigue syndrome and multiple sclerosis.

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