ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

3321–3340 of 6,161 studies

E2 ModerateCohortPEM unclearCross-Sectional

Multiple mycoplasmal infections detected in blood of patients with chronic fatigue syndrome and/or fibromyalgia syndrome.

Nasralla, M, Haier, J, Nicolson, G L·European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology·1999

Researchers tested blood samples from 91 patients with ME/CFS and/or fibromyalgia who already tested positive for mycoplasma bacteria. They found that most patients carried multiple types of mycoplasma—particularly Mycoplasma pneumoniae and Mycoplasma fermentans—and some patients had two or even three different mycoplasma species at the same time. Patients with multiple infections tended to have been sick longer, suggesting they may have picked up additional infections over time.

E2 ModerateCohortPEM not requiredCross-Sectional

The 1microg short Synacthen test in chronic fatigue syndrome.

Hudson, M, Cleare, A J·Clinical endocrinology·1999

This study tested whether people with ME/CFS have lower levels of cortisol (a stress hormone) or weaker adrenal gland responses compared to healthy people. Researchers gave small doses of a hormone called Synacthen to 20 ME/CFS patients and 20 healthy controls, then measured cortisol levels over an hour. They found no significant differences between the two groups, suggesting that reduced adrenal reserve may not explain ME/CFS symptoms.

Endocrine Disruption

E2 ModerateBehavioralPEM unclearCross-Sectional

The role of depression in pain, psychophysiological syndromes and medically unexplained symptoms associated with chronic fatigue syndrome.

Morriss, R K, Ahmed, M, Wearden, A J et al.·Journal of affective disorders·1999

This study looked at whether depression makes ME/CFS symptoms worse. Researchers compared three groups: ME/CFS patients without depression, ME/CFS patients with depression, and people with depression alone. They found that depression did not increase pain, headaches, or other unexplained symptoms in ME/CFS patients, but it did make their social life more difficult.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCross-Sectional

Attention and information processing efficiency in patients with Chronic Fatigue Syndrome.

Michiels, V, de Gucht, V, Cluydts, R et al.·Journal of clinical and experimental neuropsychology·1999

This study tested thinking and memory skills in 29 people with ME/CFS and compared them to 22 healthy people of similar age and education. The results showed that people with ME/CFS had slower thinking speed and difficulty processing information efficiently, but their ability to shift attention or focus on specific visual tasks was not notably impaired. Interestingly, memory problems appeared to stem from difficulty storing new information initially, rather than trouble recalling it later.

Cognitive Impairment

E2 ModerateCohortPEM unclearCross-Sectional

Chronic Fatigue Syndrome and Primary Fibromyalgia Syndrome as recognized by GPs.

Bazelmans, E, Vercoulen, J H, Swanink, C M et al.·Family practice·1999

This Dutch study surveyed general practitioners (GPs) to understand how often they see patients with chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS) in their practices. About 60% of GPs responded, and most reported seeing patients with these conditions. The study estimated that roughly 112 out of every 100,000 people have CFS and 157 have FMS, though these numbers are likely underestimates since some cases may go unrecognized.

Diagnostics

E2 ModerateCohortPEM unclearLongitudinal

Prognostic factors for persons with idiopathic chronic fatigue.

Hartz, A J, Kuhn, E M, Bentler, S E et al.·Archives of family medicine·1999

This study followed 199 people with chronic fatigue for 2 years to understand which factors predicted who would improve. Researchers found that people who had clearer thinking, fewer additional symptoms, better sleep patterns, and were married tended to show the most improvement in fatigue. Interestingly, when patients improved in other symptoms like depression, muscle pain, or sleep problems, their fatigue also tended to improve together.

SleepCognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Human herpesviruses in chronic fatigue syndrome.

Wallace, H L, Natelson, B, Gause, W et al.·Clinical and diagnostic laboratory immunology·1999

Researchers tested whether common viruses (HHV6, HHV7, Epstein-Barr virus, and cytomegalovirus) are more active or present in people with ME/CFS compared to healthy people. They examined blood samples from ME/CFS patients and matched healthy controls, looking for both the viruses themselves and antibodies (immune markers) against these viruses. They found no significant differences between the two groups, suggesting these particular viruses may not be a primary driver of ME/CFS.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Idiopathic chronic fatigue and chronic fatigue syndrome: a comparison of two case-definitions.

Arpino, C, Carrieri, M P, Valesini, G et al.·Annali dell'Istituto superiore di sanita·1999

This study compared how many patients were diagnosed with ME/CFS using two different diagnostic definitions from 1988 and 1994. The researchers found that the 1994 definition diagnosed more patients as having CFS, but these additional patients were less likely to have had a sudden onset of illness or signs suggesting an infectious trigger like fever or sore throat. This suggests the two definitions captured somewhat different groups of people.

Diagnostics

E2 ModerateCohortPEM unclearCase-Control

Changes in immune parameters seen in Gulf War veterans but not in civilians with chronic fatigue syndrome.

Zhang, Q, Zhou, X D, Denny, T et al.·Clinical and diagnostic laboratory immunology·1999

This study compared immune system markers in people with ME/CFS, looking separately at Gulf War veterans and non-veterans. Researchers found that Gulf War veterans with ME/CFS had different immune patterns (more of certain types of T cells, fewer NK cells, and higher levels of inflammation markers) compared to healthy veterans. However, non-veterans with ME/CFS showed no such immune differences from healthy controls, suggesting Gulf War service may have affected the immune system differently than sporadic ME/CFS.

Immune System

E2 ModerateCohortPEM not requiredObservational

Approaches to coping with chronic fatigue syndrome (CFS).

Stark, F M, Sobetzko, H M·Zentralblatt fur Hygiene und Umweltmedizin = International journal of hygiene and environmental medicine·1999

This study looked at how people with ME/CFS can better manage their condition by following long-term care and support. The researchers observed a support group over time to understand what helps patients cope with this serious illness that causes extreme fatigue and reduces ability to work, study, and maintain social activities. They found that a personalized approach combining medical care from a regular doctor and participation in a support group was helpful for disease management.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Self-reported depression and suicide attempts among U.S. women physicians.

Frank, E, Dingle, A D·The American journal of psychiatry·1999

This study surveyed over 4,500 U.S. women doctors to understand how often they experience depression and attempt suicide. The researchers found that about 1 in 5 women physicians have experienced depression at some point in their lives, and about 1.5% have attempted suicide. Several factors increased the risk, including a history of abuse, substance use, chronic fatigue syndrome, and work-related stress.

E2 ModerateCohortPEM not requiredCross-Sectional

Acute fatigue in chronic fatigue syndrome patients.

Smith, A P, Borysiewicz, L, Pollock, J et al.·Psychological medicine·1999

This study tested whether people with ME/CFS get tired more quickly during mental tasks than healthy people. Researchers compared 67 ME/CFS patients with 126 healthy controls while they performed attention tests over a long session. ME/CFS patients performed worse than healthy people, and the gap widened as fatigue set in, suggesting they struggle more with mental tiredness.

Cognitive Impairment

E2 ModerateCohortPEM not requiredLongitudinal

Natural history of severe chronic fatigue syndrome.

Hill, N F, Tiersky, L A, Scavalla, V R et al.·Archives of physical medicine and rehabilitation·1999

This study followed 23 people with severe ME/CFS over approximately 4 years to see how their illness changed over time. The researchers found that most patients stayed severely ill or showed only modest improvement, with just one person (4%) fully recovering. The study suggests that severe ME/CFS has a very poor outlook for recovery in most patients.

Severe ME

E2 ModerateBehavioralPEM not requiredCase-Control

Critical life events, infections, and symptoms during the year preceding chronic fatigue syndrome (CFS): an examination of CFS patients and subjects with a nonspecific life crisis.

Theorell, T, Blomkvist, V, Lindh, G et al.·Psychosomatic medicine·1999

This study looked at whether stressful life events and infections in the months before ME/CFS develops might play a role in triggering the illness. Researchers interviewed 46 people with ME/CFS and 46 matched control subjects without the illness, asking them to recall what happened and how they felt month-by-month for a year. They found that people who developed ME/CFS experienced more infections and stressful events—especially in the 3 months right before onset—and their fatigue, pain, and fever symptoms stayed very high even after diagnosis, unlike the control group who recovered.

E2 ModerateCohortPEM not requiredCase-Control

Chronic fatigue syndrome and nickel allergy.

Marcusson, J A, Lindh, G, Evengård, B·Contact dermatitis·1999

This study tested 50 patients with ME/CFS and 73 healthy people for allergic reactions to eight different metals. Researchers found that people with ME/CFS were more likely to be allergic to nickel—36% of ME/CFS patients had nickel allergies compared to only 19% of healthy people. This difference was especially pronounced in women with ME/CFS, where over half (52%) showed nickel allergy. The researchers suggest that nickel exposure might somehow trigger or contribute to ME/CFS in some people.

Immune System

E2 ModerateCohortPEM not requiredObservational

Metal-specific lymphocytes: biomarkers of sensitivity in man.

Stejskal, Vera DM, Danersund, Antero, Lindvall, Anders et al.·Neuro endocrinology letters·1999

This study tested whether people with ME/CFS-like symptoms had immune reactions to metals in their dental fillings and other restorations. Researchers found that many patients had immune cells that reacted to metals like mercury, nickel, and gold, and that 76% of patients who replaced their metal restorations with non-metal alternatives reported feeling better. The study suggests that metal sensitivity might trigger inflammatory responses that contribute to chronic fatigue and related conditions.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Autonomic function in patients with chronic fatigue syndrome.

Soetekouw, P M, Lenders, J W, Bleijenberg, G et al.·Clinical autonomic research : official journal of the Clinical Autonomic Research Society·1999

Researchers tested whether ME/CFS patients have problems with the part of the nervous system that automatically controls heart rate and blood pressure. They compared 37 ME/CFS patients to 38 healthy people using several tests (like standing up quickly, holding their breath, and doing mental math). The study found only minor differences, suggesting that major autonomic problems may not be the primary issue in ME/CFS, though some specific responses to stress were reduced.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Orthostatic intolerance in the chronic fatigue syndrome.

Schondorf, R, Benoit, J, Wein, T et al.·Journal of the autonomic nervous system·1999

This study looked at whether ME/CFS patients experience problems with blood pressure and heart rate when standing up quickly, a condition called orthostatic intolerance. Researchers tested 75 ME/CFS patients and 48 healthy controls using a tilt table test and other physical challenges. They found that 40% of ME/CFS patients had orthostatic intolerance compared to fewer healthy controls, suggesting this may be an important symptom in some patients that could be treated.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCase-Control

Is depression associated with immune activation?

Natelson, B H, Denny, T, Zhou, X D et al.·Journal of affective disorders·1999

Researchers tested whether depression and ME/CFS are caused by an overactive immune system. They compared immune cell counts and immune signaling molecules in people with depression, people with ME/CFS who later developed depression, and healthy controls. Surprisingly, they found no signs of immune activation in either patient group—instead, the data suggested the immune system was actually downregulated (less active) in people with depression.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Increased postwar symptoms and psychological morbidity among U.S. Navy Gulf War veterans.

Gray, G C, Kaiser, K S, Hawksworth, A W et al.·The American journal of tropical medicine and hygiene·1999

This study compared Navy veterans who served in the Gulf War to those who did not, looking for differences in health symptoms and physical condition. Gulf War veterans reported significantly more health problems, psychological difficulties, and lower physical strength than non-deployed veterans. The researchers found higher levels of certain inflammatory markers in blood tests, but couldn't pinpoint exactly what caused these differences.

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Multiple mycoplasmal infections detected in blood of patients with chronic fatigue syndrome and/or fibromyalgia syndrome.

The 1microg short Synacthen test in chronic fatigue syndrome.

The role of depression in pain, psychophysiological syndromes and medically unexplained symptoms associated with chronic fatigue syndrome.

Attention and information processing efficiency in patients with Chronic Fatigue Syndrome.

Chronic Fatigue Syndrome and Primary Fibromyalgia Syndrome as recognized by GPs.

Prognostic factors for persons with idiopathic chronic fatigue.

Human herpesviruses in chronic fatigue syndrome.

Idiopathic chronic fatigue and chronic fatigue syndrome: a comparison of two case-definitions.

Changes in immune parameters seen in Gulf War veterans but not in civilians with chronic fatigue syndrome.

Approaches to coping with chronic fatigue syndrome (CFS).

Self-reported depression and suicide attempts among U.S. women physicians.

Acute fatigue in chronic fatigue syndrome patients.

Natural history of severe chronic fatigue syndrome.

Critical life events, infections, and symptoms during the year preceding chronic fatigue syndrome (CFS): an examination of CFS patients and subjects with a nonspecific life crisis.

Chronic fatigue syndrome and nickel allergy.

Metal-specific lymphocytes: biomarkers of sensitivity in man.

Autonomic function in patients with chronic fatigue syndrome.

Orthostatic intolerance in the chronic fatigue syndrome.

Is depression associated with immune activation?

Increased postwar symptoms and psychological morbidity among U.S. Navy Gulf War veterans.

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