ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

2781–2800 of 6,188 studies

E2 ModerateCohortPEM not requiredObservational

Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function.

Hurwitz, Barry E, Coryell, Virginia T, Parker, Meela et al.·Clinical science (London, England : 1979)·2009

This study found that people with severe ME/CFS have smaller hearts and significantly less blood volume compared to healthy controls. The reduced heart size appears to be caused by having less blood circulating in their bodies, not by weak heart muscle. The researchers suggest this blood volume deficit—a condition where the body has less circulating blood than normal—may be an important factor in ME/CFS symptoms.

E2 ModerateBehavioralPEM not requiredLongitudinal

Mental morbidities and chronic fatigue in severe acute respiratory syndrome survivors: long-term follow-up.

Lam, Marco Ho-Bun, Wing, Yun-Kwok, Yu, Mandy Wai-Man et al.·Archives of internal medicine·2009

This study followed SARS survivors for over 3 years and found that many experienced long-lasting mental health problems and severe tiredness. About 40% had psychiatric illnesses, 40% reported chronic fatigue, and 27% met criteria for chronic fatigue syndrome. Healthcare workers, unemployed survivors, and those who felt socially stigmatized were at higher risk for these problems.

E2 ModerateCohortPEM not requiredCross-Sectional

Electroencephalographic correlates of Chronic Fatigue Syndrome.

Decker, Michael J, Tabassum, Humyra, Lin, Jin-Mann S et al.·Behavioral and brain functions : BBF·2009

This study looked at brain wave patterns during sleep in people with ME/CFS compared to healthy controls using a sleep study test. Researchers found that people with ME/CFS had abnormal brain wave activity during different sleep stages, particularly weaker delta waves during deep sleep and weaker alpha waves during REM sleep. These findings suggest that the problem in ME/CFS may not be the structure of sleep itself, but rather how the brain regulates and maintains restorative sleep.

Sleep

E2 ModerateCohortPEM unclearCase-Control

Risk markers for both chronic fatigue and irritable bowel syndromes: a prospective case-control study in primary care.

Hamilton, W T, Gallagher, A M, Thomas, J M et al.·Psychological medicine·2009

This study looked at whether ME/CFS and irritable bowel syndrome (IBS) share common triggers or underlying causes. Researchers compared nearly 4,400 patients with fatigue syndromes to two control groups and found that infections—especially viral infections—appeared before ME/CFS developed, while stomach infections were more common before IBS. The findings suggest that while both conditions may have similar predisposing factors, the specific triggers that cause them to develop are different.

E2 ModerateCohortPEM not requiredCase-Control

Ventricular cerebrospinal fluid lactate is increased in chronic fatigue syndrome compared with generalized anxiety disorder: an in vivo 3.0 T (1)H MRS imaging study.

Mathew, Sanjay J, Mao, Xiangling, Keegan, Kathryn A et al.·NMR in biomedicine·2009

Researchers used a specialized brain scan to measure a substance called lactate in the fluid surrounding the brain in people with ME/CFS, people with anxiety disorder, and healthy people. They found that people with ME/CFS had about three times more lactate in their brain fluid than the other groups, suggesting their brain cells may not be using energy efficiently.

Biomarkers

E2 ModerateBehavioralPEM unclearCross-Sectional

The relationship of Fennell phases to symptoms among patients with chronic fatigue syndrome.

Reynolds, Nadia L, Brown, Molly M, Jason, Leonard A·Evaluation & the health professions·2009

This study looked at whether ME/CFS symptoms change over time in predictable phases. Researchers used a questionnaire called the Fennell Phase Inventory to sort 111 patients into three groups: those in crisis (worst symptoms), stabilization (middle ground), or resolution (improving). They found that patients in the crisis phase had more depression, anxiety, worse quality of life, and used less helpful coping strategies—like avoidance—compared to those improving or stable.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Does depression mediate the relation between fatigue severity and disability in chronic fatigue syndrome sufferers?

Hadlandsmyth, Katherine, Vowles, Kevin E·Journal of psychosomatic research·2009

This study looked at how depression, fatigue, and disability are connected in people with ME/CFS. Researchers found that depression plays an important role in explaining why severe fatigue leads to disability—especially difficulties with social and emotional functioning. This suggests that treating depression alongside fatigue management might be important for improving quality of life.

E2 ModerateCohortPEM unclearCross-Sectional

Increased 8-hydroxy-deoxyguanosine, a marker of oxidative damage to DNA, in major depression and myalgic encephalomyelitis / chronic fatigue syndrome.

Maes, Michael, Mihaylova, Ivanka, Kubera, Marta et al.·Neuro endocrinology letters·2009

This study measured a marker of DNA damage in the urine of people with ME/CFS, depression, both conditions together, and healthy controls. Researchers found that people with both ME/CFS and depression had the highest levels of this DNA damage marker, and the damage correlated with fatigue severity and flu-like symptoms. This suggests that oxidative stress—a type of cellular damage from harmful molecules—may play a role in both conditions.

E2 ModerateBehavioralPEM not requiredLongitudinal

A two-year follow-up study of chronic fatigue syndrome comorbid with psychiatric disorders.

Matsuda, Yasunori, Matsui, Tokuzo, Kataoka, Kouhei et al.·Psychiatry and clinical neurosciences·2009

This study followed 70 ME/CFS patients for two years to see how psychiatric conditions like depression and anxiety affected their illness. About half the patients had these psychiatric conditions at the start. The good news: treating depression and anxiety appeared to help some patients recover from those conditions, and having psychiatric illness didn't make ME/CFS recovery worse or better.

E2 ModerateCohortPEM unclearCross-Sectional

Illness intrusiveness in myalgic encephalomyelitis: an exploratory study.

Goudsmit, E M, Stouten, B, Howes, S·Journal of health psychology·2009

This study looked at how much ME disrupts different areas of patients' lives—work, social activities, hobbies, and relationships. Researchers asked 24 people with ME about their symptoms, how disabled they felt, and their mood. They found that ME significantly intrudes on daily life, and this intrusion was linked to fatigue, brain fog, disability, and depression. Patients who had ME plus other health conditions reported even more life disruption than those with ME alone.

Cognitive Impairment

E2 ModerateCohortPEM unclearCase-Control

Vaccination as teenagers against meningococcal disease and the risk of the chronic fatigue syndrome.

Magnus, Per, Brubakk, Oddbjørn, Nyland, Harald et al.·Vaccine·2009

This study investigated whether a meningococcal vaccine given to teenagers in Norway in 1988-1989 was linked to the later development of ME/CFS. Researchers compared 201 people diagnosed with ME/CFS to 389 people without the condition and found no meaningful difference in vaccination rates between the two groups. The findings suggest that receiving this particular vaccine as a teenager does not increase the risk of developing ME/CFS.

E2 ModerateCohortPEM not requiredCross-Sectional

An assessment of prospective memory retrieval in women with chronic fatigue syndrome using a virtual-reality environment: an initial study.

Attree, Elizabeth A, Dancey, Christine P, Pope, Alison L·Cyberpsychology & behavior : the impact of the Internet, multimedia and virtual reality on behavior and society·2009

This study examined memory problems in women with ME/CFS using a computer-based virtual environment. Researchers tested two types of memory: remembering things after they happen (like recalling a list of words) and remembering to do something in the future (like remembering to take medication). Women with ME/CFS showed noticeable difficulties with both types of memory, particularly with recalling information, though some future-memory tasks showed only subtle differences.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCross-Sectional

Chronic fatigue syndrome and DSM-IV personality disorders.

Courjaret, Joachime, Schotte, Christiaan K W, Wijnants, Herlindis et al.·Journal of psychosomatic research·2009

This study looked at whether ME/CFS patients have more personality disorders than people without ME/CFS. Researchers tested 50 women with ME/CFS and compared them to 50 healthy women and 50 women with psychiatric conditions. They found that women with ME/CFS had similar personality traits and rates of personality disorders as healthy women, suggesting that personality problems are not a major cause of ME/CFS.

E2 ModerateCohortPEM not requiredCross-Sectional

Association of peripheral inflammatory markers with chronic fatigue in a population-based sample.

Raison, Charles L, Lin, Jin-Mann S, Reeves, William C·Brain, behavior, and immunity·2009

Researchers measured inflammation markers in the blood of people with ME/CFS, people with fatigue that didn't quite meet ME/CFS criteria, and healthy controls. They found that inflammation markers were elevated in both fatigue groups compared to healthy people. However, when they accounted for factors like depression, weight, age, and medications, the connection to ME/CFS specifically became less clear, suggesting that general fatigue and unwellness—not ME/CFS alone—may be linked to immune activation.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Detection of herpesviruses and parvovirus B19 in gastric and intestinal mucosa of chronic fatigue syndrome patients.

Frémont, Marc, Metzger, Kristine, Rady, Hamada et al.·In vivo (Athens, Greece)·2009

Researchers looked for viral DNA from four viruses (HHV-6, HHV-7, EBV, and parvovirus B19) in the stomach and intestine samples from 48 ME/CFS patients and 35 healthy controls. They found that parvovirus B19 was much more common in patients with ME/CFS (40%) compared to healthy people (less than 15%), suggesting it may play a role in the illness for some patients. The other viruses were found at similar rates in both groups.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

A comparison of patients with chronic fatigue syndrome in two "ideologically" contrasting clinics.

Van Houdenhove, Boudewijn, Van Hoof, Elke, Becq, Katrien et al.·The Journal of nervous and mental disease·2009

This study compared ME/CFS patients from two Belgian clinics—one focused on biological causes and one on psychological/social factors. Researchers found that patients at both clinics were actually quite similar in terms of fatigue levels, mood problems, and confidence in managing their illness. However, patients who experienced a sudden illness onset and believed their condition was physical in nature were more likely to attend the biologically-focused clinic.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Memory for fatigue in chronic fatigue syndrome: relationships to fatigue variability, catastrophizing, and negative affect.

Sohl, Stephanie J, Friedberg, Fred·Behavioral medicine (Washington, D.C.)·2008

This study explored how ME/CFS patients remember their fatigue compared to what they actually experience day-to-day. Over 3 weeks, 53 patients recorded their fatigue levels as they happened, then recalled how fatigued they had been the previous week. The research found that people who had more variable fatigue, as well as those struggling with worry, depression, or anxiety, tended to remember their fatigue differently than they actually experienced it.

E2 ModerateCohortPEM not requiredCross-Sectional

Sexual dysfunction as related to severity of fatigue in women with CFS.

Blazquez, A, Ruiz, E, Vazquez, A et al.·Journal of sex & marital therapy·2008

This study looked at whether sexual function problems are connected to fatigue severity in women with ME/CFS. Researchers compared 27 women with ME/CFS to 15 healthy women and used questionnaires to measure sexual satisfaction, interest, and comfort. They found that women with more severe fatigue reported more sexual problems, including less satisfaction, avoiding sexual activity, and viewing sex negatively.

E2 ModerateBehavioralPEM not requiredObservational

Implementing cognitive behavior therapy for chronic fatigue syndrome in mental health care: a costs and outcomes analysis.

Scheeres, Korine, Wensing, Michel, Bleijenberg, Gijs et al.·BMC health services research·2008

This study tested whether cognitive behavior therapy (CBT), a talk-based treatment, could be successfully offered to ME/CFS patients at a mental health center and whether it was worth the cost. Researchers tracked 125 patients before and after treatment and found that 37% recovered from CFS, patients' healthcare costs went down, and overall costs to society were lower. The study suggests that offering CBT for ME/CFS in mental health settings could be both helpful and financially reasonable.

Interventions

E2 ModerateCohortPEM not requiredCross-Sectional

Memory for fatigue in chronic fatigue syndrome: the relation between weekly recall and momentary ratings.

Friedberg, Fred, Sohl, Stephanie J·International journal of behavioral medicine·2008

This study looked at how people with ME/CFS remember their fatigue levels compared to what they report in the moment. Over three weeks, 71 participants rated their fatigue six times daily using electronic diaries, then recalled their fatigue levels at the end of each week. The researchers found that people's weekly memories of fatigue were higher than their day-to-day ratings, but the two measures still matched moderately well overall.

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Evidence browser

Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function.

Mental morbidities and chronic fatigue in severe acute respiratory syndrome survivors: long-term follow-up.

Electroencephalographic correlates of Chronic Fatigue Syndrome.

Risk markers for both chronic fatigue and irritable bowel syndromes: a prospective case-control study in primary care.

Ventricular cerebrospinal fluid lactate is increased in chronic fatigue syndrome compared with generalized anxiety disorder: an in vivo 3.0 T (1)H MRS imaging study.

The relationship of Fennell phases to symptoms among patients with chronic fatigue syndrome.

Does depression mediate the relation between fatigue severity and disability in chronic fatigue syndrome sufferers?

Increased 8-hydroxy-deoxyguanosine, a marker of oxidative damage to DNA, in major depression and myalgic encephalomyelitis / chronic fatigue syndrome.

A two-year follow-up study of chronic fatigue syndrome comorbid with psychiatric disorders.

Illness intrusiveness in myalgic encephalomyelitis: an exploratory study.

Vaccination as teenagers against meningococcal disease and the risk of the chronic fatigue syndrome.

An assessment of prospective memory retrieval in women with chronic fatigue syndrome using a virtual-reality environment: an initial study.

Chronic fatigue syndrome and DSM-IV personality disorders.

Association of peripheral inflammatory markers with chronic fatigue in a population-based sample.

Detection of herpesviruses and parvovirus B19 in gastric and intestinal mucosa of chronic fatigue syndrome patients.

A comparison of patients with chronic fatigue syndrome in two "ideologically" contrasting clinics.

Memory for fatigue in chronic fatigue syndrome: relationships to fatigue variability, catastrophizing, and negative affect.

Sexual dysfunction as related to severity of fatigue in women with CFS.

Implementing cognitive behavior therapy for chronic fatigue syndrome in mental health care: a costs and outcomes analysis.

Memory for fatigue in chronic fatigue syndrome: the relation between weekly recall and momentary ratings.

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