ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

4741–4760 of 6,163 studies

E3 PreliminaryReviewPEM not requiredReview-Narrative

Fibromyalgia: A Critical and Comprehensive Review.

Borchers, Andrea T, Gershwin, M Eric·Clinical reviews in allergy & immunology·2015

Fibromyalgia is a condition that causes widespread pain, fatigue, and sleep problems, and it shares many symptoms with other conditions that are hard to diagnose. This review explains that while some people think fibromyalgia might be caused by infection, inflammation, or injury, there is not strong evidence supporting these ideas. The authors recommend that treatment should focus on education, exercise, physical therapy, and approved medications rather than opioids.

Pain and SensitizationSleepDiagnostics

E3 PreliminaryReviewPEM unclearReview-Narrative

Fibromyalgia and chronic fatigue: the underlying biology and related theoretical issues.

Romano, Graziella F, Tomassi, Simona, Russell, Alice et al.·Advances in psychosomatic medicine·2015

This review examines what scientists have learned about the biological causes of ME/CFS and fibromyalgia. Researchers have found that three main systems in the body appear to go wrong: inflammation (the body's immune response), oxidative stress (cellular damage from harmful molecules), and problems with hormones that control stress responses. These abnormalities may explain why patients experience fatigue, pain, memory problems, and mood changes.

Energy Metabolism

E3 PreliminaryReviewPEM unclearReview-Narrative

Central pathways causing fatigue in neuro-inflammatory and autoimmune illnesses.

Morris, Gerwyn, Berk, Michael, Walder, Ken et al.·BMC medicine·2015

This review proposes that ME/CFS fatigue may be caused by ongoing inflammation and immune system activation in the body, which then damages the brain's support cells (astrocytes) and energy-producing structures (mitochondria). The authors suggest that ME/CFS shares similar biological mechanisms with other inflammatory diseases like multiple sclerosis and lupus, and recommend that ME/CFS patients be tested for immune activation and receive specific brain imaging to look for evidence of inflammation.

NeuroinflammationImmune System

E3 PreliminaryMechanismPEM not requiredObservational

Sleep quality and the treatment of intestinal microbiota imbalance in Chronic Fatigue Syndrome: A pilot study.

Jackson, Melinda L, Butt, Henry, Ball, Michelle et al.·Sleep science (Sao Paulo, Brazil)·2015

This small study tested whether reducing certain bacteria in the gut could improve sleep in people with ME/CFS. Researchers gave 21 participants a short course of antibiotics and measured changes in their gut bacteria and sleep. Seven participants showed significant reduction in a type of bacteria called Streptococcus, and these people did sleep better after treatment. However, most participants' gut bacteria returned to their original state, suggesting the antibiotic effects didn't last.

Sleep

E3 PreliminaryDiagnosticPEM unclearMethods-Paper

Variability in Symptoms Complicates Utility of Case Definitions.

McManimen, Stephanie L, Jason, Leonard A, Williams, Yolonda J·Fatigue : biomedicine, health & behavior·2015

This study looked at how ME/CFS is defined and diagnosed across different research centers. Researchers found that when different studies measure key symptoms like post-exertional malaise (feeling worse after activity), unrefreshing sleep, and brain fog, they get very different numbers—suggesting that either different patients are being studied, or researchers are asking questions in different ways. The study concluded that ME/CFS research needs more standardized, consistent methods for measuring symptoms so findings can be compared fairly.

Post-Exertional Malaise

E3 PreliminaryMechanismPEM unclearObservational

B-Lymphocyte Depletion in Myalgic Encephalopathy/ Chronic Fatigue Syndrome. An Open-Label Phase II Study with Rituximab Maintenance Treatment.

Fluge, Øystein, Risa, Kristin, Lunde, Sigrid et al.·PloS one·2015

This study tested whether removing B-cells (immune cells) using a drug called rituximab could help ME/CFS patients. Twenty-nine patients received rituximab infusions over 15 months and were followed for 3 years. Eighteen patients (62%) showed lasting improvement in fatigue, with some staying better for over 2 years, though improvements took several months to appear.

Immune System

E3 PreliminaryReviewPEM requiredReview-Narrative

Review of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: an evidence-based approach to diagnosis and management by clinicians.

Bested, Alison C, Marshall, Lynn M·Reviews on environmental health·2015

This review helps doctors understand ME/CFS better by explaining what it is, how to diagnose it, and how to treat it. ME/CFS is a serious illness that causes extreme tiredness, brain fog, pain, and sleep problems that get worse after physical activity. The review emphasizes that pacing activities—carefully balancing rest with gentle exercise—is one of the most important strategies patients can use to manage their symptoms and avoid crashes.

Post-Exertional Malaise

E3 PreliminaryCommentaryPEM requiredEditorial

Reflections on the Institute of Medicine's systemic exertion intolerance disease.

Jason, Leonard A, Sunnquist, Madison, Brown, Abigail et al.·Polskie Archiwum Medycyny Wewnetrznej·2015

The Institute of Medicine proposed renaming chronic fatigue syndrome to 'systemic exertion intolerance disease' (SEID) and created new diagnostic criteria. This editorial critiques that change, noting that most patients rejected the new name and the new criteria were not tested on actual patient populations before being recommended. The new criteria may incorrectly identify more people as having the disease while missing key features that define it.

Post-Exertional Malaise

E3 PreliminaryCohortPEM not requiredCase-Control

Are stamina and fatigue polar opposites? A case study.

So, Suzanna, Evans, Meredyth, Jason, Leonard A et al.·Journal of prevention & intervention in the community·2015

This study looked at whether fatigue and stamina are opposite sides of the same coin in ME/CFS. The researchers found that some people with ME/CFS have low fatigue but still cannot do much physically, while others have high fatigue that stops them from being active. This suggests that fatigue and stamina may be separate issues, and current diagnostic criteria that focus mainly on fatigue might miss people who have low energy and endurance but don't report severe fatigue.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM unclearMethods-Paper

Test-Retest Reliability of the DePaul Symptom Questionnaire.

Jason, Leonard A, So, Suzanna, Brown, Abigail A et al.·Fatigue : biomedicine, health & behavior·2015

Researchers tested whether the DePaul Symptom Questionnaire (DSQ)—a tool designed to help doctors diagnose ME/CFS—gives consistent results when used multiple times. They asked 26 people with ME/CFS and 25 healthy people to answer the same questions at different times. The questionnaire proved reliable, meaning patients' answers were consistent, making it a trustworthy tool for identifying who has ME/CFS.

Diagnostics

E3 PreliminaryReviewPEM unclearReview-Narrative

Mitoprotective dietary approaches for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Caloric restriction, fasting, and ketogenic diets.

Craig, Courtney·Medical hypotheses·2015

This study explores whether certain dietary approaches—like eating fewer calories, fasting, or following a ketogenic (low-carb, high-fat) diet—might help ME/CFS symptoms by protecting the mitochondria, which are the energy-producing parts of our cells. The authors review evidence suggesting that ME/CFS involves problems with mitochondrial function and immune activation that exhausts these cellular power plants. They propose that these three dietary strategies may help restore mitochondrial health and reduce symptoms, though they note that more research is needed to test this in actual ME/CFS patients.

Immune System

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms.

Twisk, Frank Nm·World journal of methodology·2015

ME and CFS are often treated as the same condition, but they are actually different illnesses with some overlapping symptoms. ME has specific features like muscle weakness, brain fog, heart and circulation problems, and especially a distinctive symptom called post-exertional malaise—where patients feel much worse after even small amounts of activity. Because many ME/CFS symptoms feel subjective, some doctors have questioned whether they are real physical problems, but this article argues that objective medical tests can measure key symptoms and help doctors diagnose these conditions more accurately.

Cognitive ImpairmentPost-Exertional Malaise

E3 PreliminaryPEM unclear

"United We Stand": Framing Myalgic Encephalomyelitis in a Virtual Symbolic Community.

Lian, Olaug S, Nettleton, Sarah·Qualitative health research·2015

This study looked at how people with ME/CFS connect and support each other on Norwegian internet forums. Researchers analyzed discussions across 14 online communities to understand what brings these groups together and how they create shared meaning around their condition. The study found that these online communities help people with ME/CFS feel less alone and may influence how society views their illness.

E3 PreliminaryReviewPEM unclearReview-Narrative

Exercise, not to exercise, or how to exercise in patients with chronic pain? Applying science to practice.

Daenen, Liesbeth, Varkey, Emma, Kellmann, Michael et al.·The Clinical journal of pain·2015

This review examines how exercise affects people with chronic pain, including ME/CFS. While exercise helps many chronic pain conditions, some patients—especially those with ME/CFS, fibromyalgia, and chronic whiplash—experience worsening symptoms or 'crashes' after exercising. The authors emphasize that exercise programs need to be carefully tailored to each person, with proper recovery time built in, rather than using a one-size-fits-all approach.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

Problems in defining post-exertional malaise.

Jason, Leonard A, Evans, Meredyth, So, Suzanna et al.·Journal of prevention & intervention in the community·2015

This study looked at how post-exertional malaise (PEM)—the characteristic worsening of symptoms after physical or mental effort—is measured in ME/CFS patients. Researchers asked 32 people with CFS to answer survey questions about PEM and found that small changes in how questions are worded can change whether someone is diagnosed with PEM. This suggests that the current ways of diagnosing this condition may not be reliable or consistent.

Post-Exertional Malaise

E3 PreliminaryDiagnosticPEM not requiredMethods-Paper

Effects of Time Frame on the Recall Reliability of CFS Symptoms.

Evans, Meredyth, Jason, Leonard A·Evaluation & the health professions·2015

This study looked at how accurately people with ME/CFS can remember and report their symptoms depending on how far back they think about (one week, one month, or six months). Researchers found that asking patients to recall symptoms from the past six months was most reliable for most symptoms, though joint pain was best recalled over one month. This matters because doctors need to know the best time frame to ask about when diagnosing ME/CFS.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

TMD and chronic pain: a current view.

Furquim, Bruno D'Aurea, Flamengui, Lívia Maria Sales Pinto, Conti, Paulo César Rodrigues·Dental press journal of orthodontics·2015

This review examines how temporomandibular disorders (jaw joint and muscle problems) develop and persist. The authors found that chronic muscle pain in the jaw works similarly to other widespread pain conditions like fibromyalgia and ME/CFS—through a process called central sensitization where the nervous system becomes overly sensitive to pain signals. They explain that genetics and nervous system function influence whether symptoms improve or worsen.

Autonomic Nervous System

E3 PreliminaryDiagnosticPEM requiredMethods-Paper

Capturing the post-exertional exacerbation of fatigue following physical and cognitive challenge in patients with chronic fatigue syndrome.

Keech, Andrew, Sandler, Carolina X, Vollmer-Conna, Ute et al.·Journal of psychosomatic research·2015

This study developed a new questionnaire called the Fatigue and Energy Scale (FES) to measure the specific type of exhaustion that ME/CFS patients experience after physical or mental activity. Researchers talked with 19 patients to understand what their fatigue feels like, then tested the questionnaire with patients doing exercise, driving simulation, and everyday tasks. The results showed that the FES successfully captured both the physical tiredness and mental fog that worsens after activity in ME/CFS.

Post-Exertional Malaise

E3 PreliminaryReviewPEM unclearReview-Narrative

The Role of Toll-Like Receptors in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: A New Promising Therapeutic Approach?

Gambuzza, Maria Elsa, Salmeri, Francesca Maria, Soraci, Luca et al.·CNS & neurological disorders drug targets·2015

This review examines how certain immune system sensors called Toll-like receptors (TLRs) may contribute to ME/CFS. These receptors sit on cells in the gut and detect bacteria and other microbes, triggering inflammation that may spread to the brain and cause fatigue and other symptoms. The researchers suggest that targeting these TLRs with new medications might help reduce inflammation and improve symptoms.

NeuroinflammationGut MicrobiomeImmune System

E3 PreliminaryCommentaryPEM requiredEditorial

Living with ME/CFS. challenge for scientists?

Weiler, John J A·Neuro endocrinology letters·2015

This case describes a person with ME/CFS for 19 years who experienced an unusual pattern: they could run 10 kilometers without problems, but later that same day, 30 minutes of browsing for books triggered severe exhaustion, muscle pain, and brain fog lasting into the next day. This puzzling difference highlights how ME/CFS symptoms don't always follow expected patterns and suggests that exercise intolerance in ME/CFS may be more complex than previously thought.

Post-Exertional Malaise

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Fibromyalgia: A Critical and Comprehensive Review.

Fibromyalgia and chronic fatigue: the underlying biology and related theoretical issues.

Central pathways causing fatigue in neuro-inflammatory and autoimmune illnesses.

Sleep quality and the treatment of intestinal microbiota imbalance in Chronic Fatigue Syndrome: A pilot study.

Variability in Symptoms Complicates Utility of Case Definitions.

B-Lymphocyte Depletion in Myalgic Encephalopathy/ Chronic Fatigue Syndrome. An Open-Label Phase II Study with Rituximab Maintenance Treatment.

Review of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: an evidence-based approach to diagnosis and management by clinicians.

Reflections on the Institute of Medicine's systemic exertion intolerance disease.

Are stamina and fatigue polar opposites? A case study.

Test-Retest Reliability of the DePaul Symptom Questionnaire.

Mitoprotective dietary approaches for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Caloric restriction, fasting, and ketogenic diets.

Accurate diagnosis of myalgic encephalomyelitis and chronic fatigue syndrome based upon objective test methods for characteristic symptoms.

"United We Stand": Framing Myalgic Encephalomyelitis in a Virtual Symbolic Community.

Exercise, not to exercise, or how to exercise in patients with chronic pain? Applying science to practice.

Problems in defining post-exertional malaise.

Effects of Time Frame on the Recall Reliability of CFS Symptoms.

TMD and chronic pain: a current view.

Capturing the post-exertional exacerbation of fatigue following physical and cognitive challenge in patients with chronic fatigue syndrome.

The Role of Toll-Like Receptors in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: A New Promising Therapeutic Approach?

Living with ME/CFS. challenge for scientists?

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