ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2785 studies

2421–2440 of 2,785 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Lack of seasonal variation of symptoms in patients with chronic fatigue syndrome.

García-Borreguero, D, Dale, J K, Rosenthal, N E et al.·Psychiatry research·1998

Many people experience changes in energy, mood, appetite, and sleep across different seasons, often feeling worse in winter. This study tested whether ME/CFS patients experience these same seasonal changes. The researchers found that ME/CFS patients actually show much less seasonal variation in their symptoms compared to healthy people, suggesting their fatigue and other symptoms stay relatively constant year-round rather than fluctuating with the seasons.

Sleep

E2 ModerateCohortPEM not requiredCross-Sectional

Multiplex PCR for the detection of Mycoplasma fermentans, M. hominis and M. penetrans in cell cultures and blood samples of patients with chronic fatigue syndrome.

Choppa, P C, Vojdani, A, Tagle, C et al.·Molecular and cellular probes·1998

Researchers developed a test to detect three types of bacteria called mycoplasmas in blood samples from ME/CFS patients and healthy people. They found these bacteria were much more common in ME/CFS patients (52% had some mycoplasma species) compared to healthy controls (15%), suggesting a possible link between these infections and ME/CFS.

E2 ModerateCohortPEM not requiredCross-Sectional

Exploring the validity of the Chalder Fatigue scale in chronic fatigue syndrome.

Morriss, R K, Wearden, A J, Mullis, R·Journal of psychosomatic research·1998

This study tested whether the Chalder Fatigue Scale—a common questionnaire used to measure tiredness in ME/CFS patients—actually measures what it claims to measure. Researchers analyzed responses from 136 ME/CFS patients and found that fatigue has four distinct components: mental tiredness (linked to thinking problems), sleep difficulties, physical weakness (linked to low fitness), and depression. The results suggest the 11-item version of the scale works better than the original 14-item version for measuring fatigue in ME/CFS.

SleepCognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Cancer and a fatiguing illness in Northern Nevada--a causal hypothesis.

Levine, P H, Fears, T R, Cummings, P et al.·Annals of epidemiology·1998

Researchers compared cancer rates in two areas of Nevada where an unexplained fatiguing illness (including ME/CFS cases) occurred in the 1980s against an area with no reported illness. They found higher rates of non-Hodgkin lymphoma and brain tumors in the affected areas, but similar rates of breast and lung cancer. The authors suggest this could mean ME/CFS might increase cancer risk, but they emphasize it's too early to draw firm conclusions.

E2 ModerateCohortPEM not requiredObservational

Amplified amplitudes of circadian rhythms and nighttime hypotension in patients with chronic fatigue syndrome: improvement by inopamil but not by melatonin.

van de Luit, L, van der Meulen, J, Cleophas, T J et al.·Angiology·1998

This study found that people with ME/CFS have unusually large swings in heart rate and blood pressure throughout the day and night, even though the overall pattern matches healthy controls. Importantly, their nighttime blood pressure drops too low (below 100 mm Hg systolic), which may contribute to fatigue and other symptoms. When treated with a heart-strengthening medication called inopamil, nighttime blood pressure improved, but melatonin actually made it worse.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Long- and short-term blood pressure and RR-interval variability and psychosomatic distress in chronic fatigue syndrome.

Duprez, D A, De Buyzere, M L, Drieghe, B et al.·Clinical science (London, England : 1979)·1998

Researchers compared blood pressure and heart rate patterns in people with ME/CFS to healthy controls. They found that people with ME/CFS had normal blood pressure readings, but their heart rates were consistently higher. When lying down, people with ME/CFS also showed reduced variability in blood pressure patterns compared to healthy controls.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCase-Control

[Risk factors for ischemic heart disease in patients with chronic fatigue syndrome].

Vilikus, Z, Marecková, H, Janatková, I et al.·Sbornik lekarsky·1998

This study compared heart disease risk factors between people with ME/CFS and healthy controls. Researchers found that despite ME/CFS patients exercising less overall, they had no higher risk for heart disease than the control group. This suggests that reduced exercise activity in ME/CFS does not appear to increase cardiovascular risk in the way it might in other conditions.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Effects of exercise on cognitive and motor function in chronic fatigue syndrome and depression.

Blackwood, S K, MacHale, S M, Power, M J et al.·Journal of neurology, neurosurgery, and psychiatry·1998

This study compared how people with ME/CFS, people with depression, and healthy people performed on thinking and strength tests before and after exercise on a treadmill. People with ME/CFS reported feeling much more tired and struggling harder during the exercise than the other groups. After exercising, people with ME/CFS had bigger drops in their ability to focus and pay attention compared to healthy people, suggesting that exercise affects their thinking ability in a specific way.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Prevalence of chronic fatigue syndrome in a community population in Japan.

Kawakami, N, Iwata, N, Fujihara, S et al.·The Tohoku journal of experimental medicine·1998

This Japanese study looked at how common ME/CFS is in everyday communities by interviewing 137 people. Researchers found that about 1 in 67 people had severe, persistent fatigue that met ME/CFS criteria and significantly disrupted their daily life. The findings suggested ME/CFS might be more common in Japan than in Western countries studied previously.

Diagnostics

E2 ModerateBehavioralPEM not requiredCross-Sectional

Early life stress, negative paternal relationships, and chemical intolerance in middle-aged women: support for a neural sensitization model.

Bell, I R, Baldwin, C M, Russek, L G et al.·Journal of women's health·1998

This study looked at whether women with chemical sensitivity (difficulty tolerating everyday chemicals) had experienced more childhood stress or difficult relationships with their fathers compared to women with depression alone or women without these conditions. The researchers found that women with chemical sensitivity had weaker relationships with their fathers and showed signs of nervous system overactivity. The study suggests that repeated exposure to stress early in life might train the nervous system to react more strongly to chemicals and other triggers.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCase-Control

Chronic fatigue syndrome in psychiatric patients: lifetime and premorbid personal history of physical health.

Endicott, N A·Psychosomatic medicine·1998

This study compared 46 ME/CFS patients with two groups of psychiatric patients without ME/CFS to see if there were differences in their past physical health histories. Researchers found that ME/CFS patients reported more lifetime infections (including repeated mono-like illnesses), irritable bowel syndrome, and allergies before developing ME/CFS than the comparison groups. This suggests that a pattern of poor overall physical health earlier in life may play a role in developing ME/CFS.

E2 ModerateCohortPEM not requiredObservational

Alteration of spatial-temporal parameters of gait in Chronic Fatigue Syndrome patients.

Saggini, R, Pizzigallo, E, Vecchiet, J et al.·Journal of the neurological sciences·1998

This study looked at how people with ME/CFS walk compared to healthy people. Researchers used specialized movement analysis tools to measure walking patterns in 12 patients and found clear differences in how smoothly and symmetrically they walked. Interestingly, these walking problems appeared right from the start of walking, not after fatigue set in, suggesting the issue may be related to how the brain controls movement rather than muscle tiredness.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome and seasonal affective disorder: comorbidity, diagnostic overlap, and implications for treatment.

Terman, M, Levine, S M, Terman, J S et al.·The American journal of medicine·1998

This study looked at whether ME/CFS symptoms get worse during winter months, similar to seasonal depression. Researchers asked 110 ME/CFS patients about their symptoms in summer and winter, and found that about one-third showed a seasonal pattern with winter worsening. This suggests that some ME/CFS patients might benefit from light therapy, a treatment commonly used for seasonal depression.

Sleep

E2 ModerateCohortPEM not requiredCross-Sectional

Evaluating neuropsychological impairment in chronic fatigue syndrome.

Vercoulen, J H, Bazelmans, E, Swanink, C M et al.·Journal of clinical and experimental neuropsychology·1998

This study looked at whether people with ME/CFS have problems with thinking, memory, and concentration. Researchers tested patients using standard cognitive tests and also asked them to report their own memory and concentration difficulties. Surprisingly, most patients performed normally on the tests, and there was no clear connection between test results and what patients reported experiencing in daily life.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCase-Control

Naloxone-mediated activation of the hypothalamic-pituitary-adrenal axis in chronic fatigue syndrome.

Scott, L V, Burnett, F, Medbak, S et al.·Psychological medicine·1998

This study looked at whether an opioid-blocking drug called naloxone could trigger the body's stress hormone system in ME/CFS patients versus healthy people. The researchers found that when given naloxone, ME/CFS patients had a blunted response in one stress hormone (ACTH) compared to healthy controls, suggesting that excess opioids are not the primary cause of the stress hormone problems seen in ME/CFS.

Endocrine Disruption

E2 ModerateCohortPEM not requiredCross-Sectional

Diurnal variation of adrenocortical activity in chronic fatigue syndrome.

MacHale, S M, Cavanagh, J T, Bennie, J et al.·Neuropsychobiology·1998

This study measured stress hormone (cortisol) levels in 30 ME/CFS patients and 15 healthy controls at different times of day. The researchers found that while individual cortisol measurements were similar between groups, ME/CFS patients showed a flattened pattern—their cortisol levels didn't drop as much in the evening as they should. Higher evening cortisol levels were connected to worse overall health and physical functioning in ME/CFS patients.

Endocrine Disruption

E2 ModerateCohortPEM unclearCross-Sectional

Secretion of growth hormone in patients with chronic fatigue syndrome.

Berwaerts, J, Moorkens, G, Abs, R·Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society·1998

This study looked at growth hormone levels in people with ME/CFS, because low growth hormone has been seen in related conditions like fibromyalgia. Researchers tested 20 ME/CFS patients and compared them to healthy controls, measuring growth hormone in different ways. They found that ME/CFS patients had lower levels of a growth hormone marker (IGF-I) and tended to produce less growth hormone at night, though other growth hormone tests were similar between groups.

Endocrine Disruption

E2 ModerateBehavioralPEM not requiredCross-Sectional

Adaptive tasks, coping and quality of life of chronically ill patients: the cases of Parkinson's disease and chronic fatigue syndrome.

De Ridder, D T, Schreurs, K M, Bensing, J M·Journal of health psychology·1998

This study compared how people with Parkinson's disease and ME/CFS cope with the challenges their illnesses create and how this affects their quality of life. Researchers found that while both groups face similar types of challenges (like managing symptoms and adjusting daily life), the way these challenges affect quality of life differs between the two diseases. For people with ME/CFS, how patients think about and evaluate their illness challenges was more important in predicting their quality of life than the actual severity of their symptoms.

E2 ModerateCohortPEM not requiredCross-Sectional

Low levels of serum acylcarnitine in chronic fatigue syndrome and chronic hepatitis type C, but not seen in other diseases.

Kuratsune, H, Yamaguti, K, Lindh, G et al.·International journal of molecular medicine·1998

Researchers measured a substance called acylcarnitine in the blood of people with ME/CFS and compared it to healthy people and those with other diseases. They found that people with ME/CFS had significantly lower levels of this substance, and this same pattern appeared in both Japanese and Swedish patients. Importantly, this low level was only seen in ME/CFS and one other condition (chronic hepatitis C), not in other common diseases like diabetes or high blood pressure.

BiomarkersEnergy Metabolism

E2 ModerateCohortPEM not requiredCross-Sectional

Core body temperature is normal in chronic fatigue syndrome.

Hamilos, D L, Nutter, D, Gershtenson, J et al.·Biological psychiatry·1998

Many people with ME/CFS report feeling like they have a low body temperature or mild fever, but this study found that their actual core body temperature is normal. Researchers continuously measured body temperature every 5 minutes for 24 hours in people with ME/CFS and compared them to healthy people, those with allergies, and those with depression. All groups had similar normal temperatures and similar daily temperature patterns.

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Lack of seasonal variation of symptoms in patients with chronic fatigue syndrome.

Multiplex PCR for the detection of Mycoplasma fermentans, M. hominis and M. penetrans in cell cultures and blood samples of patients with chronic fatigue syndrome.

Exploring the validity of the Chalder Fatigue scale in chronic fatigue syndrome.

Cancer and a fatiguing illness in Northern Nevada--a causal hypothesis.

Amplified amplitudes of circadian rhythms and nighttime hypotension in patients with chronic fatigue syndrome: improvement by inopamil but not by melatonin.

Long- and short-term blood pressure and RR-interval variability and psychosomatic distress in chronic fatigue syndrome.

[Risk factors for ischemic heart disease in patients with chronic fatigue syndrome].

Effects of exercise on cognitive and motor function in chronic fatigue syndrome and depression.

Prevalence of chronic fatigue syndrome in a community population in Japan.

Early life stress, negative paternal relationships, and chemical intolerance in middle-aged women: support for a neural sensitization model.

Chronic fatigue syndrome in psychiatric patients: lifetime and premorbid personal history of physical health.

Alteration of spatial-temporal parameters of gait in Chronic Fatigue Syndrome patients.

Chronic fatigue syndrome and seasonal affective disorder: comorbidity, diagnostic overlap, and implications for treatment.

Evaluating neuropsychological impairment in chronic fatigue syndrome.

Naloxone-mediated activation of the hypothalamic-pituitary-adrenal axis in chronic fatigue syndrome.

Diurnal variation of adrenocortical activity in chronic fatigue syndrome.

Secretion of growth hormone in patients with chronic fatigue syndrome.

Adaptive tasks, coping and quality of life of chronically ill patients: the cases of Parkinson's disease and chronic fatigue syndrome.

Low levels of serum acylcarnitine in chronic fatigue syndrome and chronic hepatitis type C, but not seen in other diseases.

Core body temperature is normal in chronic fatigue syndrome.

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