ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

81–100 of 381 studies

E2 ModeratePEM unclearModerate confidenceCross-SectionalEditor reviewed

Phase-dependent trends in the prevalence of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) related to long COVID: A criteria-based retrospective study in Japan.

Morita, Satoru, Tokumasu, Kazuki, Otsuka, Yuki et al.·PloS one·2024

This study looked at 739 patients with long COVID to understand how many developed ME/CFS and what factors were involved. Researchers found that ME/CFS affected about 8% of long COVID patients, but the rate varied depending on which COVID variant caused the initial infection—it was much higher (24%) in early COVID but dropped significantly (3%) during the Omicron wave. Brain fog complaints increased over time, even as strict ME/CFS diagnoses became less common.

Cognitive Impairment

E2 ModeratePEM unclearModerate confidenceRegistry-ResourceEditor reviewed

Longterm course of neuropsychological symptoms and ME/CFS after SARS-CoV-2-infection: a prospective registry study.

Reuken, P A, Besteher, B, Finke, K et al.·European archives of psychiatry and clinical neuroscience·2024

This study followed over 1,000 people who had long-lasting symptoms after COVID-19 infection. Researchers found that about 31% of patients met the diagnostic criteria for ME/CFS at their first visit, but this dropped to 19% at a second visit months later. While patients reported feeling less fatigued and having fewer concentration problems over time, many continued to experience long-lasting symptoms that significantly affected their daily lives.

Cognitive ImpairmentLong COVID Overlap

E2 ModeratePEM unclearPreliminaryObservationalEditor reviewed

Low-dose Naltrexone Improves post-COVID-19 condition Symptoms.

Tamariz, Leonardo, Bast, Elizabeth, Klimas, Nancy et al.·Clinical therapeutics·2024

This study looked at whether treatments used for ME/CFS could help people with long COVID. Researchers reviewed records from 108 patients who tried different treatments including low-dose naltrexone, amitriptyline, duloxetine, and physical therapy. They found that patients taking low-dose naltrexone were about 5 times more likely to improve compared to those doing physical therapy alone, with improvements in both fatigue and pain.

Pain and SensitizationCognitive Impairment

E2 ModeratePEM not requiredModerate confidenceCross-SectionalEditor reviewed

Cognitive reserve as a protective factor against cognitive impairment in chronic fatigue syndrome.

Surendran, Gopika, Jose, Tony P·Applied neuropsychology. Adult·2024

This study examined whether people's life experiences and education—called 'cognitive reserve'—help protect them from the thinking and memory problems common in ME/CFS. Researchers tested 91 people with ME/CFS and found that those with more cognitive reserve had fewer cognitive problems. The severity of someone's ME/CFS was the main factor affecting both cognitive reserve and cognitive problems, rather than age or gender.

Cognitive Impairment

E2 ModeratePEM not requiredModerate confidenceCross-SectionalEditor reviewed

[The Significance of Chronic Fatigue in the Post-Covid Consultation and its Consequences for Outpatient Rehabilitation in the Context of Statutory Accident Insurance].

Dalichau, Stefan, Kordy, Henrike, Klüver, Janna et al.·Psychotherapie, Psychosomatik, medizinische Psychologie·2024

This study looked at 454 people (mostly women aged 40–60) who developed long-term fatigue after COVID-19. Nearly all of them reported severe tiredness, and over 73% also experienced brain fog. The fatigue lasted about 14–15 months on average and significantly affected their ability to work and enjoy daily life. The researchers recommend that treatment should focus on managing chronic fatigue similar to ME/CFS, using education and practical coping strategies rather than trying to 'cure' the condition.

Cognitive Impairment

E2 ModeratePEM unclearModerate confidenceCross-SectionalEditor reviewed

Plasma Neurofilament Light Chain: A Potential Biomarker for Neurological Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Azcue, Naiara, Tijero-Merino, Beatriz, Acera, Marian et al.·Biomedicines·2024

Researchers measured a protein called neurofilament light chain (NfL) in the blood of ME/CFS patients and healthy people. They found that ME/CFS patients had higher levels of this protein, which suggests nerve damage in the brain and nervous system. The patients with higher NfL levels also had more problems with memory, thinking clearly, and with their autonomic nervous system (the part that controls heart rate and other automatic body functions).

Autonomic Nervous SystemCognitive Impairment

E2 ModeratePEM not requiredPreliminaryCross-SectionalEditor reviewed

Investigating brain cortical activity in patients with post-COVID-19 brain fog.

Wojcik, Grzegorz M, Shriki, Oren, Kwasniewicz, Lukasz et al.·Frontiers in neuroscience·2023

This study looked at brain electrical activity in people who had COVID-19 and experienced 'brain fog'—persistent mental cloudiness that can last several months. Researchers compared three groups using advanced brain scans while people performed thinking tasks, and used computer algorithms to see if they could distinguish between those with brain fog, those without it, and healthy controls. They found measurable differences in brain activity patterns between the groups, suggesting brain fog has a detectable physical basis in the brain.

Cognitive Impairment

E2 ModeratePEM not requiredModerate confidenceCross-SectionalEditor reviewed

A comparison of pain, fatigue, and function between post-COVID-19 condition, fibromyalgia, and chronic fatigue syndrome: a survey study.

Haider, Saman, Janowski, Adam J, Lesnak, Joseph B et al.·Pain·2023

This study surveyed 707 people with post-COVID-19, fibromyalgia, and/or ME/CFS to compare their symptoms. Researchers found that all three conditions share similar patterns of pain, fatigue, brain fog, anxiety, and depression that impact daily life. People with post-COVID-19 reported somewhat less severe pain and fatigue than those with fibromyalgia or ME/CFS, but those with multiple diagnoses had worse symptoms overall.

Pain and SensitizationCognitive Impairment

E2 ModeratePEM unclearModerate confidenceObservationalEditor reviewed

Cognitive impairment in post-acute sequelae of COVID-19 and short duration myalgic encephalomyelitis patients is mediated by orthostatic hemodynamic changes.

Day, Heather, Yellman, Brayden, Hammer, Sarah et al.·Frontiers in neuroscience·2023

This study examined why people with ME/CFS and long COVID experience 'brain fog' and memory problems. Researchers tested how well people could think and remember before and after standing up quickly (which can make blood pressure drop). They found that people with these illnesses had more trouble thinking clearly after the standing test, and this was linked to unusual changes in their heart rate and blood pressure. The findings suggest that problems with blood flow to the brain during physical stress may be contributing to cognitive difficulties.

Autonomic Nervous SystemCognitive Impairment

E2 ModeratePEM unclearPreliminaryCross-SectionalEditor reviewed

Urine Metabolite Analysis to Identify Pathomechanisms of Long COVID: A Pilot Study.

Taenzer, Maja, Löffler-Ragg, Judith, Schroll, Andrea et al.·International journal of tryptophan research : IJTR·2023

This study examined urine samples from people with Long COVID and ME/CFS to look for chemical imbalances that might explain their symptoms. Researchers found that both groups had lower levels of certain amino acids and neurotransmitters (brain chemicals) compared to healthy people, particularly affecting energy production, mood, and sleep. These chemical signatures could potentially be used as simple urine tests to help doctors understand what is happening in patients and create personalized treatments.

SleepAutonomic Nervous SystemCognitive Impairment

E2 ModeratePEM unclearPreliminaryCross-SectionalEditor reviewed

Subcortical and default mode network connectivity is impaired in myalgic encephalomyelitis/chronic fatigue syndrome.

Inderyas, Maira, Thapaliya, Kiran, Marshall-Gradisnik, Sonya et al.·Frontiers in neuroscience·2023

This study used advanced brain imaging to compare how different brain regions communicate in people with ME/CFS versus healthy people. Researchers found that certain connections between the brainstem (the lower part of the brain) and cerebellum (involved in balance and coordination) are weakened in ME/CFS patients. These brain communication problems may help explain why people with ME/CFS experience fatigue, memory problems, and other symptoms.

Cognitive Impairment

E2 ModeratePEM not requiredModerate confidenceCross-SectionalEditor reviewed

The association between the number of symptoms and the severity of Post-COVID-Fatigue after SARS-CoV-2 infection treated in an outpatient setting.

Schmidbauer, Lena, Kirchberger, Inge, Goßlau, Yvonne et al.·Journal of neurology·2023

This study looked at 425 people who had mild-to-moderate COVID-19 treated as outpatients and followed them for about 8 months afterward. Researchers found that 37% of these people developed long-lasting fatigue (Post-COVID-Fatigue), and those who had more symptoms during their initial infection and ongoing symptoms were more likely to experience severe fatigue. The more symptoms someone had, the worse their fatigue tended to be.

Cognitive Impairment

E2 ModeratePEM unclearModerate confidenceCross-SectionalEditor reviewed

Dysautonomia and small fiber neuropathy in post-COVID condition and Chronic Fatigue Syndrome.

Azcue, N, Del Pino, R, Acera, M et al.·Journal of translational medicine·2023

This study compared how the nervous system works differently in people with ME/CFS, people with long COVID, and healthy people. Researchers tested heart rate responses, sweating patterns, and how nerves respond to temperature. They found that people with ME/CFS had more severe problems with heart rate regulation and nerve fiber damage than those with long COVID, and both groups had more problems than healthy controls.

Autonomic Nervous SystemCognitive Impairment

E2 ModeratePEM unclearModerate confidenceCross-SectionalEditor reviewed

The Conners Continuous Performance Test CPT3™: Is it a reliable marker to predict neurocognitive dysfunction in Myalgic encephalomyelitis/chronic fatigue syndrome?

Fernández-Quirós, Judith, Lacasa-Cazcarra, Marcos, Alegre-Martín, Jose et al.·Frontiers in psychology·2023

This study tested whether a computer-based attention test called CPT3™ can reliably detect thinking and concentration problems in ME/CFS patients. Researchers compared 158 ME/CFS patients with 67 healthy people and found that ME/CFS patients performed significantly worse on measures of attention, focus, and reaction speed. The test successfully identified differences between the two groups, suggesting it could be a useful tool for doctors to help diagnose or monitor ME/CFS.

Cognitive Impairment

E2 ModeratePEM not requiredModerate confidenceCase-ControlEditor reviewed

Post-acute sequelae of COVID-19 in young adults: Mental fatigue and decreased cognitive flexibility.

Sedat, Yasin, Erman, Altunisik, Yasemin, Firat Ekmekyapar·Ideggyogyaszati szemle·2023

This study looked at young adults who had COVID-19 and compared them to those who hadn't. Researchers found that people who had COVID-19 reported more mental fatigue (difficulty concentrating and feeling mentally tired) and had more trouble switching between different tasks. These problems lasted long after the initial infection, suggesting COVID-19 may have lasting effects on how the brain works.

Cognitive Impairment

E2 ModeratePEM unclearPreliminaryObservationalEditor reviewed

Physical Activity Effects on Muscle Fatigue in Sport in Active Adults with Long COVID-19: An Observational Study.

Coscia, Francesco, Mancinelli, Rosa, Gigliotti, Paola Virginia et al.·Diagnostics (Basel, Switzerland)·2023

This study looked at how physical activity affected fatigue and other symptoms in people with Long COVID-19. Researchers compared people who stayed active with those who were sedentary and tracked their symptoms over 6 to 12 months. They found that people who remained physically active experienced a larger drop in fatigue over time compared to those who were inactive, though both groups still had muscle weakness and sleep problems.

SleepCognitive Impairment

E2 ModeratePEM requiredModerate confidenceCross-SectionalEditor reviewed

Connectivity Between Salience and Default Mode Networks and Subcortical Nodes Distinguishes Between Two Classes of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Su, Jiasheng, Thapaliya, Kiran, Eaton-Fitch, Natalie et al.·Brain connectivity·2023

This study used brain imaging (fMRI) to examine how different brain networks communicate in people with ME/CFS compared to healthy controls. Researchers found that people with ME/CFS have different patterns of brain connectivity, particularly in networks involved in attention and the brain's rest-state activity. Importantly, the study discovered that two different diagnostic criteria for ME/CFS (ICC and Fukuda) appear to identify distinct brain differences, suggesting they may represent different disease types.

Cognitive Impairment

E2 ModeratePEM not requiredModerate confidenceObservationalEditor reviewed

Characteristics of Sleep Disturbance in Patients with Long COVID: A Retrospective Observational Study in Japan.

Sunada, Naruhiko, Nakano, Yasuhiro, Otsuka, Yuki et al.·Journal of clinical medicine·2022

This study looked at sleep problems in 363 long COVID patients in Japan and found that about 16.5% had significant sleep disturbance. People infected during the Omicron wave were twice as likely to have sleep problems compared to those infected during the Delta wave. Patients with sleep disturbance also reported more fatigue, brain fog, headaches, and anxiety, and had abnormal stress hormone levels suggesting their bodies were under persistent stress.

SleepCognitive Impairment

E2 ModeratePEM unclearModerate confidenceCross-SectionalEditor reviewed

Brain fog of post-COVID-19 condition and Chronic Fatigue Syndrome, same medical disorder?

Azcue, N, Gómez-Esteban, J C, Acera, M et al.·Journal of translational medicine·2022

This study compared brain fog and fatigue symptoms in people with ME/CFS and those recovering from COVID-19 to see if they might be the same condition triggered by different causes. Both groups showed similar problems with fatigue, sleep, and muscle pain, but people with ME/CFS had more severe cognitive difficulties like trouble concentrating and processing information. Interestingly, loss of smell that lasted a long time in COVID-19 patients appeared connected to their cognitive problems.

Cognitive Impairment

E2 ModeratePEM unclearModerate confidenceCross-SectionalEditor reviewed

Bright, but allergic and neurotic? A critical investigation of the "overexcitable genius" hypothesis.

Fries, Jonathan, Baudson, Tanja Gabriele, Kovacs, Kristof et al.·Frontiers in psychology·2022

This study looked at whether highly intelligent people (members of MENSA) experience more health problems than the general population. Researchers surveyed over 600 high-IQ individuals across five European countries and found that chronic fatigue syndrome was about 5.7 times more common in this group compared to the general public. Other conditions like depression, anxiety, and autism spectrum disorders were also significantly more common, but surprisingly, allergies and autoimmune diseases were not.

Cognitive Impairment

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Phase-dependent trends in the prevalence of myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) related to long COVID: A criteria-based retrospective study in Japan.

Longterm course of neuropsychological symptoms and ME/CFS after SARS-CoV-2-infection: a prospective registry study.

Low-dose Naltrexone Improves post-COVID-19 condition Symptoms.

Cognitive reserve as a protective factor against cognitive impairment in chronic fatigue syndrome.

[The Significance of Chronic Fatigue in the Post-Covid Consultation and its Consequences for Outpatient Rehabilitation in the Context of Statutory Accident Insurance].

Plasma Neurofilament Light Chain: A Potential Biomarker for Neurological Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Investigating brain cortical activity in patients with post-COVID-19 brain fog.

A comparison of pain, fatigue, and function between post-COVID-19 condition, fibromyalgia, and chronic fatigue syndrome: a survey study.

Cognitive impairment in post-acute sequelae of COVID-19 and short duration myalgic encephalomyelitis patients is mediated by orthostatic hemodynamic changes.

Urine Metabolite Analysis to Identify Pathomechanisms of Long COVID: A Pilot Study.

Subcortical and default mode network connectivity is impaired in myalgic encephalomyelitis/chronic fatigue syndrome.

The association between the number of symptoms and the severity of Post-COVID-Fatigue after SARS-CoV-2 infection treated in an outpatient setting.

Dysautonomia and small fiber neuropathy in post-COVID condition and Chronic Fatigue Syndrome.

The Conners Continuous Performance Test CPT3™: Is it a reliable marker to predict neurocognitive dysfunction in Myalgic encephalomyelitis/chronic fatigue syndrome?

Post-acute sequelae of COVID-19 in young adults: Mental fatigue and decreased cognitive flexibility.

Physical Activity Effects on Muscle Fatigue in Sport in Active Adults with Long COVID-19: An Observational Study.

Connectivity Between Salience and Default Mode Networks and Subcortical Nodes Distinguishes Between Two Classes of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Characteristics of Sleep Disturbance in Patients with Long COVID: A Retrospective Observational Study in Japan.

Brain fog of post-COVID-19 condition and Chronic Fatigue Syndrome, same medical disorder?

Bright, but allergic and neurotic? A critical investigation of the "overexcitable genius" hypothesis.

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