ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2768 studies

2061–2080 of 2,768 studies

E2 ModerateCohortPEM not requiredCross-Sectional

The feeling of fatigue--fatigue severity by unidimensional versus composite questionnaires.

Naschitz, Jochanan E, Rozenbaum, Michael, Shaviv, Nomi et al.·Behavioral medicine (Washington, D.C.)·2004

This study compared two different questionnaires used to measure fatigue in ME/CFS patients and other groups with fatigue. Researchers found that a simple one-question fatigue scale and a more detailed multi-part fatigue scale gave very similar results, suggesting the simpler tool works just as well for tracking how severe someone's fatigue is.

E2 ModerateCohortPEM unclearCross-Sectional

Working memory deficits in chronic fatigue syndrome: differentiating between speed and accuracy of information processing.

Deluca, John, Christodoulou, Christopher, Diamond, Bruce J et al.·Journal of the International Neuropsychological Society : JINS·2004

This study tested how quickly people with ME/CFS can process information (like reading or hearing something fast) and how well they can hold information in their working memory (like remembering a phone number while writing it down). The researchers found that people with ME/CFS without mental health conditions had slower information processing speeds, but their memory ability was normal. Interestingly, people with ME/CFS who also had depression or anxiety showed similar results to healthy people.

Cognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Salivary cortisol response to awakening in chronic fatigue syndrome.

Roberts, Amanda D L, Wessely, Simon, Chalder, Trudie et al.·The British journal of psychiatry : the journal of mental science·2004

This study tested how well the body's stress response system (controlled by the brain and hormones) works in ME/CFS patients. Researchers measured cortisol, a stress hormone, in saliva when people first woke up and for an hour afterward. They found that people with ME/CFS had a weaker cortisol response compared to healthy people, suggesting their stress-response system may not be working properly.

Endocrine Disruption

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome and sexual dysfunction.

Vermeulen, Ruud C W, Scholte, Hans R·Journal of psychosomatic research·2004

This study examined whether women with ME/CFS experience more sexual problems than healthy women. Researchers surveyed 35 women with ME/CFS and 36 healthy women using questionnaires about fatigue and sexual function. Interestingly, the women with ME/CFS reported similar levels of sexual satisfaction as healthy women, even though they had significantly higher fatigue levels.

E2 ModerateCohortPEM not requiredCross-Sectional

Study of immune alterations in patients with chronic fatigue syndrome with different etiologies.

Racciatti, D, Dalessandro, M, Delle Donne, L et al.·International journal of immunopathology and pharmacology·2004

This study looked at immune system cells in people with ME/CFS to see if there were differences compared to healthy people. Researchers tested blood samples from 139 ME/CFS patients and 36 healthy controls, examining specific types of white blood cells. They found that people with ME/CFS had lower counts of certain immune cells, suggesting the immune system may play a role in causing or maintaining the condition.

Immune System

E2 ModerateBehavioralPEM not requiredObservational

Kinesiophobia in chronic fatigue syndrome: assessment and associations with disability.

Nijs, Jo, De Meirleir, Kenny, Duquet, William·Archives of physical medicine and rehabilitation·2004

This study looked at whether ME/CFS patients who fear movement (kinesiophobia) have more activity limitations than others. Researchers used a questionnaire to measure fear of movement and found that patients with higher fear of movement reported more difficulty with daily activities, but this fear did not actually relate to how much exercise capacity they had when tested on a bike.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Chronic fatigue syndrome impairs circadian rhythm of activity level.

Tryon, Warren W, Jason, Lenny, Frankenberry, Erin et al.·Physiology & behavior·2004

This study looked at how people with ME/CFS move and rest throughout the day and night by using activity monitors worn on the waist. Researchers found that people with ME/CFS were less active during the day and had less predictable patterns of activity and rest compared to healthy people. These disrupted patterns may help explain why ME/CFS patients experience fatigue and other symptoms.

Sleep

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue and indicators of long-term employment disability in psychosomatic inpatients.

Tritt, Karin, Nickel, Marius, Mitterlehner, Ferdinand et al.·Wiener klinische Wochenschrift·2004

This study looked at 1,000 patients at a hospital clinic to understand why some people with severe, persistent exhaustion become unable to work. The researchers found that patients who couldn't work had stronger focus on physical symptoms, difficulty recognizing their own feelings, and trouble getting along with coworkers—not necessarily because they were sicker, but because of how they coped with their condition.

E2 ModerateCohortPEM not requiredCase-Control

Monozygotic twins discordant for chronic fatigue syndrome: objective measures of sleep.

Ball, Nigel, Buchwald, Dedra S, Schmidt, Douglas et al.·Journal of psychosomatic research·2004

This study compared sleep patterns between people with ME/CFS and their healthy identical twins using objective sleep monitoring. While people with ME/CFS showed some differences—including more deep sleep, more REM sleep, and more breathing interruptions during sleep—most standard sleep measurements were similar between the two groups. The researchers concluded that sleep structure problems alone don't fully explain why ME/CFS patients experience such severe sleep complaints.

E2 ModerateCohortPEM not requiredCross-Sectional

Sociodemographic and symptom correlates of fatigue in an adolescent primary care sample.

Mears, Cynthia J, Taylor, Renee R, Jordan, Karen M et al.·The Journal of adolescent health : official publication of the Society for Adolescent Medicine·2004

This study looked at how common fatigue lasting more than one month is in teenagers visiting primary care clinics. Researchers found that about 8% of teens had prolonged fatigue and 4.4% had symptoms matching CFS-like illness. Teens with prolonged fatigue were more likely to also experience headaches, muscle pain, fever, and fatigue that worsened with exercise.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Sleep assessment in a population-based study of chronic fatigue syndrome.

Unger, Elizabeth R, Nisenbaum, Rosane, Moldofsky, Harvey et al.·BMC neurology·2004

This study looked at sleep problems in 339 people with ME/CFS from Kansas to understand how sleep issues relate to their fatigue. Researchers found that over 80% of ME/CFS patients had at least one sleep problem, with non-restorative sleep (sleep that doesn't feel refreshing) and restlessness being the most common. Interestingly, ME/CFS patients were not unusually sleepy during the day, which suggests their fatigue comes from a different mechanism than typical sleep deprivation.

Sleep

E2 ModerateCohortPEM not requiredObservational

Disability evaluation in chronic fatigue syndrome: associations between exercise capacity and activity limitations/participation restrictions.

Nijs, J, De Meirleir, K, Wolfs, S et al.·Clinical rehabilitation·2004

This study looked at whether ME/CFS patients with lower exercise capacity also have more difficulty with daily activities. Researchers tested 77 patients on an exercise bike and asked them to report how limited they were in everyday life. They found a modest connection between poor exercise performance and activity limitations, but the link was not strong enough to predict disability from exercise tests alone.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome: lack of association between pain-related fear of movement and exercise capacity and disability.

Nijs, Jo, Vanherberghen, Katrien, Duquet, William et al.·Physical therapy·2004

Many ME/CFS patients with pain avoid movement because they fear it will make them worse (a condition called kinesiophobia). This study tested whether this fear of movement actually relates to how much exercise patients can do or how disabled they are. Researchers found that fear of movement was common in ME/CFS patients, but surprisingly, it did not predict exercise capacity or activity limitations.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Objective assessment of personality disorder in chronic fatigue syndrome.

Henderson, Max, Tannock, Charles·Journal of psychosomatic research·2004

This study looked at whether people with ME/CFS have personality traits that might be associated with mental health conditions. Researchers interviewed 61 ME/CFS patients, 40 people with depression, and 45 healthy students using a structured clinical assessment tool. They found that 39% of ME/CFS patients had identifiable personality patterns, which was higher than healthy people but lower than those with depression—and importantly, this wasn't simply explained by having depression alongside ME/CFS.

E2 ModerateCohortPEM not requiredCase-Control

The distribution of white blood cell fat oxidation in health and disease.

Pendergast, D R, Fisher, N M, Meksawan, K et al.·Journal of inherited metabolic disease·2004

This study looked at how white blood cells use fat for energy in different groups of people, including those with ME/CFS. Researchers measured fat burning in blood cells from healthy controls, people with ME/CFS, people with other conditions, and athletes. They found that people with ME/CFS had unusually high fat oxidation in their white blood cells, while people with a genetic disorder (CPT II deficiency) had very low fat oxidation.

Energy Metabolism

E2 ModerateCohortPEM not requiredObservational

Prediction of peak oxygen uptake in patients fulfilling the 1994 CDC criteria for chronic fatigue syndrome.

Nijs, Jo, De Meirleir, Kenny·Clinical rehabilitation·2004

This study looked for a simple way to predict how much oxygen someone with ME/CFS can use during exercise (called VO2peak), which is a measure of exercise capacity. Researchers tested 240 ME/CFS patients on exercise bikes and found that by measuring the maximum workload a patient could achieve, they could estimate their oxygen use fairly accurately with a simple calculation.

E2 ModerateCohortPEM not requiredCase-Control

Gastric emptying is slow in chronic fatigue syndrome.

Burnet, Richard B, Chatterton, Barry E·BMC gastroenterology·2004

This study found that people with ME/CFS often have stomach problems that can be measured with special imaging tests. Researchers compared 32 ME/CFS patients with 45 healthy people and discovered that most ME/CFS patients had slower movement of food through their stomachs, particularly liquids. These measured stomach delays matched up with how severe patients' digestive symptoms were.

E2 ModerateCohortPEM not requiredCross-Sectional

The specificity of the CDC-1994 criteria for chronic fatigue syndrome: comparison of health status in three groups of patients who fulfill the criteria.

Kennedy, Gwen, Abbot, Neil C, Spence, Vance et al.·Annals of epidemiology·2004

This study looked at whether the standard definition of ME/CFS is specific enough to identify a single disease. Researchers compared three groups of patients who all met the official diagnostic criteria but got sick in different ways: some had gradual onset, some developed symptoms after Gulf War service, and some after pesticide exposure. They found important differences between these groups in their physical symptoms and emotional health, suggesting the current definition may be catching different conditions.

Diagnostics

E2 ModerateCohortPEM not requiredLongitudinal

Chronic fatigue syndrome in adolescents: a follow-up study.

Gill, Anna C, Dosen, Ana, Ziegler, John B·Archives of pediatrics & adolescent medicine·2004

This study followed teenagers with severe fatigue for up to 8 years to see how many got better. Teenagers who had been fatigued for less than 6 months all recovered completely. Those diagnosed with ME/CFS had worse outcomes, with less than a quarter showing near-complete improvement, though some did get partially better. Being admitted to the hospital did not change whether teenagers recovered or not.

E2 ModerateCohortPEM unclearCase-Control

Peripheral cholinergic function in humans with chronic fatigue syndrome, Gulf War syndrome and with illness following organophosphate exposure.

Khan, Faisel, Kennedy, Gwen, Spence, Vance A et al.·Clinical science (London, England : 1979)·2004

Researchers tested how blood vessels in the forearm respond to acetylcholine (a chemical messenger in the body) in people with ME/CFS, Gulf War illness, and pesticide exposure. They found that people with ME/CFS had an unusually strong vascular response to acetylcholine, but people with the other two conditions had normal responses. This suggests ME/CFS may involve a specific problem with how the body breaks down acetylcholine in blood vessels.

Autonomic Nervous System

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The feeling of fatigue--fatigue severity by unidimensional versus composite questionnaires.

Working memory deficits in chronic fatigue syndrome: differentiating between speed and accuracy of information processing.

Salivary cortisol response to awakening in chronic fatigue syndrome.

Chronic fatigue syndrome and sexual dysfunction.

Study of immune alterations in patients with chronic fatigue syndrome with different etiologies.

Kinesiophobia in chronic fatigue syndrome: assessment and associations with disability.

Chronic fatigue syndrome impairs circadian rhythm of activity level.

Chronic fatigue and indicators of long-term employment disability in psychosomatic inpatients.

Monozygotic twins discordant for chronic fatigue syndrome: objective measures of sleep.

Sociodemographic and symptom correlates of fatigue in an adolescent primary care sample.

Sleep assessment in a population-based study of chronic fatigue syndrome.

Disability evaluation in chronic fatigue syndrome: associations between exercise capacity and activity limitations/participation restrictions.

Chronic fatigue syndrome: lack of association between pain-related fear of movement and exercise capacity and disability.

Objective assessment of personality disorder in chronic fatigue syndrome.

The distribution of white blood cell fat oxidation in health and disease.

Prediction of peak oxygen uptake in patients fulfilling the 1994 CDC criteria for chronic fatigue syndrome.

Gastric emptying is slow in chronic fatigue syndrome.

The specificity of the CDC-1994 criteria for chronic fatigue syndrome: comparison of health status in three groups of patients who fulfill the criteria.

Chronic fatigue syndrome in adolescents: a follow-up study.

Peripheral cholinergic function in humans with chronic fatigue syndrome, Gulf War syndrome and with illness following organophosphate exposure.

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