ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

1181–1200 of 6,157 studies

E2 ModerateCohortPEM not requiredCross-Sectional

Comprehensive Assessment of Autonomic Nervous System Profiles in Postural Orthostatic Tachycardia Syndrome Among Syncope, Chronic Fatigue, and Post-COVID-19 Patients.

Milovanovic, Branislav, Markovic, Nikola, Petrovic, Masa et al.·Diagnostics (Basel, Switzerland)·2025

This study examined how the nervous system functions differently in people with POTS (a condition causing rapid heart rate when standing) who also have fainting episodes, ME/CFS, or post-COVID illness. Researchers used heart rate monitors, tilt tests, and breathing exercises to measure how well the autonomic nervous system—which controls heart rate and blood pressure—works in each group. They found that POTS appears differently depending on what condition causes it: in syncope patients it involves sympathetic overdrive, while in ME/CFS patients it involves parasympathetic weakness.

Autonomic Nervous System

E2 ModerateCohortPEM unclearCross-Sectional

Babesia and Bartonella Species DNA in Blood and Enrichment Blood Cultures from People with Chronic Fatigue and Concurrent Neurological Symptoms.

Breitschwerdt, Edward B, Maggi, Ricardo G, Bush, Janice C et al.·Pathogens (Basel, Switzerland)·2025

This study looked for two types of bacteria—Babesia and Bartonella—in the blood of 50 people with ME/CFS and neurological symptoms. Researchers used special DNA tests to detect these bacteria. They found that about 24% of participants had Babesia infection and 26% had Bartonella infection, suggesting these bacteria might play a role in some ME/CFS cases.

E2 ModerateCohortPEM not requiredCross-Sectional

Adverse effects of obesity on overall health, quality of life, and related physical health metrics: A cross-sectional and longitudinal study from the All of Us Research Program.

Yao, Zhiqi, Tchang, Beverly G, Chae, Kacey et al.·Journal of internal medicine·2025

This study looked at over 323,000 people in the United States to understand how obesity affects overall health and quality of life. Researchers found that people with higher body weight reported worse health, more pain, more fatigue, and greater difficulty with physical activity compared to people of normal weight. The effects were strongest in people with the most severe obesity, who were nearly 4 times more likely to report poor health and severe pain.

Pain and SensitizationSleep

E2 ModerateCohortPEM unclearCross-Sectional

A Multidimensional Assessment of Sleep Disorders in Long COVID Using the Alliance Sleep Questionnaire.

Wilson, Alina, Ricciardiello Mejia, Giorgio Camillo, Lomba, Sara et al.·Healthcare (Basel, Switzerland)·2025

This study looked at sleep problems in 200 people with Long COVID seen at Stanford's clinic. Researchers found that more than half had breathing-related sleep issues, about 4 in 10 had insomnia, and about 3 in 10 had excessive daytime sleepiness. The study identified two different groups of patients: one with more severe sleep and systemic symptoms than the other.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

The Physical and Mental Health of Post-9/11 Female and Male Veterans: Findings from the Comparative Health Assessment Interview Research Study.

Dursa, Erin K, Cypel, Yasmin S, Culpepper, William J et al.·Journal of women's health (2002)·2025

This study surveyed thousands of veterans from recent U.S. military operations to compare the health problems experienced by female and male veterans. Female veterans reported chronic fatigue syndrome, along with several other conditions like arthritis, migraine, and depression, at higher rates than male veterans. The findings show that both female and male veterans who had deployed experienced more health problems overall compared to non-veterans.

E2 ModerateCohortPEM not requiredLongitudinal

Tracking Persistent Symptoms in Scotland (TraPSS): a longitudinal prospective cohort study of COVID-19 recovery after mild acute infection.

Sculthorpe, Nicholas F, McLaughlin, Marie, Cerexhe, Luke et al.·BMJ open·2025

This study followed 287 people in Scotland for 9 months after they had mild COVID-19 to track how long symptoms lasted. By month 9, only 3.1% still had ongoing symptoms matching Long-COVID criteria. Fatigue was the symptom that lasted longest, while cough improved quickly. The study found that older people were more likely to report pain and thinking problems, and women were more likely to experience headaches and post-exertional malaise (feeling worse after activity).

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Unmasking the Long-Term Effects of COVID-19 With a Focus on Chronic Fatigue Syndrome: A Community-Based Study From India.

Gupta, Arti, Rajan, Vishnu, Aravindakshan, Rajeev et al.·Cureus·2025

This study looked at 500 COVID-19 survivors in rural India to see how many developed chronic fatigue syndrome (CFS)—a condition causing severe, lasting tiredness and other symptoms. About 21% of the COVID-19 survivors developed CFS, with older people, women, and those with existing health conditions at higher risk. The study found that fatigue, joint pain, and muscle pain were common problems after COVID-19.

Long COVID Overlap

E2 ModerateCohortPEM unclearCross-Sectional

Putting the PASC Score to the Test: Clinical vs. Statistical Accuracy in Long COVID Diagnosis.

Azola, Alba, Dastgheyb, Raha M, Easter, Rebecca et al.·Journal of general internal medicine·2025

Researchers tested a scoring tool called the PASC score to see if it could correctly identify long COVID patients. They compared 130 long COVID patients with 60 people who recovered completely from COVID-19. The PASC score was very accurate at confirming who had long COVID, but missed about 20% of actual patients. A simpler approach using just three symptoms (loss of smell/taste, post-exertional malaise, or sexual dysfunction) worked even better at catching long COVID cases.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredObservational

Does Prenatal SARS-CoV-2 Infection Exacerbate Postpartum Lower Urinary Tract Symptoms? A Multicenter Retrospective Cohort Study.

Lyu, Yu Han, Li, Min, Yao, Hui Qing et al.·Biomedical and environmental sciences : BES·2025

This study examined whether pregnant people who had COVID-19 experienced more urinary symptoms (like leakage or urgency) after giving birth compared to those who didn't have COVID-19. Researchers surveyed 3,652 women at two hospitals in China and found that COVID-19 infection during pregnancy did not increase reported urinary problems. However, they did find that the muscles controlling urination showed different electrical activity in women who had COVID-19, suggesting the virus may affect how these muscles work at a deeper level.

E2 ModerateCohortPEM not requiredCross-Sectional

Cross-Sectional Study Evaluating the Role of Autonomic Nervous System Functional Diagnostics in Differentiating Post-Infectious Syndromes: Post-COVID Syndrome, Chronic Fatigue Syndrome, and Lyme Disease.

Milovanovic, Branislav, Markovic, Nikola, Petrovic, Masa et al.·Biomedicines·2025

This study compared how the nervous system functions differently in people with Post-COVID syndrome, ME/CFS (both COVID-related and unrelated), and late-stage Lyme disease—three conditions that often feel similar but may have different causes. Researchers tested 758 patients using heart rhythm monitors, tilt tests, and blood pressure measurements to see how their bodies responded to position changes and stress. They found that Lyme disease patients showed a distinct pattern of nerve dysfunction (adrenergic failure), while Post-COVID and ME/CFS patients had different types of nervous system imbalances.

Autonomic Nervous System

E2 ModerateCohortPEM not requiredCross-Sectional

Cognitive functioning in patients with chronic fatigue syndrome: Slowed information processing or a deficit in attentional selectivity?

Banovic, Ingrid, Šaban, Iva, Ayad, Adel et al.·Neuropsychology·2025

This study tested whether people with ME/CFS have trouble focusing their attention or simply process information more slowly. Researchers gave 83 ME/CFS patients and 83 healthy people a simple attention test (the Stroop task) where they had to name colors while ignoring conflicting words. The results showed that ME/CFS patients were slower overall, but their difficulty wasn't due to problems with attention—it was purely because their brains processed information more slowly.

Cognitive Impairment

E2 ModerateCohortPEM unclearLongitudinal

Three-Month Follow-Up of the Post-COVID Syndrome after Admission to a Specialised Post-COVID Centre-A Prospective Study Focusing on Mental Health with Patient Reported Outcome Measures (PROMs).

Schäfer, Isabel Cecil, Krehbiel, Johannes, Adler, Werner et al.·International journal of environmental research and public health·2024

Researchers followed 265 Post-COVID patients for about 5 months to understand how mental health symptoms changed over time. They found that most patients still had severe Post-COVID symptoms, with nearly 9 in 10 reporting extreme fatigue and about half experiencing depression. Importantly, while depression and anxiety improved somewhat over time, fatigue and post-exertional malaise (getting worse after activity) stayed at very high levels and did not improve.

Post-Exertional Malaise

E2 ModerateMechanismPEM unclearMechanistic

Data-independent LC-MS/MS analysis of ME/CFS plasma reveals a dysregulated coagulation system, endothelial dysfunction, downregulation of complement machinery.

Nunes, Massimo, Vlok, Mare, Proal, Amy et al.·Cardiovascular diabetology·2024

Researchers analyzed blood proteins in 15 ME/CFS patients and 10 healthy controls to look for differences that might explain ME/CFS symptoms. They found that ME/CFS patients had abnormal levels of proteins involved in blood clotting, blood vessel function, and immune system regulation. These findings suggest that problems with blood clotting and blood vessel health may play a role in ME/CFS.

BiomarkersImmune System

E2 ModerateCohortPEM not requiredCross-Sectional

Validity and diagnostic overlap of functional somatic syndrome diagnoses.

van der Meulen, Monica L, Bos, Martje, Bakker, Stephan J L et al.·Journal of psychosomatic research·2024

This study looked at how often three common conditions—ME/CFS, fibromyalgia, and irritable bowel syndrome—occur together in the general population. Researchers surveyed nearly 90,000 people and found that these conditions overlap far more often than would happen by pure chance, especially when they last longer and cause more serious symptoms. This suggests these conditions may share common underlying features.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Perceived misdiagnosis of psychiatric conditions in autistic adults.

Kentrou, Vasiliki, Livingston, Lucy A, Grove, Rachel et al.·EClinicalMedicine·2024

This study found that many autistic adults, especially women, were given different psychiatric diagnoses (like depression, anxiety, or personality disorders) before being correctly diagnosed with autism. About 1 in 4 autistic adults and 1 in 3 autistic women reported receiving at least one psychiatric diagnosis that they felt was wrong. This delayed their access to proper autism support and treatment.

E2 ModerateCohortPEM unclearCase-Control

Hypothalamus Connectivity in Adolescent Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Byrne, Hollie, Knight, Sarah J, Josev, Elisha K et al.·Journal of neuroscience research·2024

Researchers used brain imaging (MRI) to look at a small brain region called the hypothalamus in teenagers with ME/CFS compared to healthy teenagers. They found some differences in how the hypothalamus connects to other parts of the brain in people with ME/CFS, and these differences appeared related to how long someone had been sick and how severe their fatigue was. This is one of the first studies to examine this specific brain region in adolescents with ME/CFS.

E2 ModerateBehavioralPEM not requiredLongitudinal

All-or-Nothing Behavior and Catastrophic Thinking Predict Fatigue in Inflammatory Bowel Disease: A Prospective Cohort Study.

Moulton, Calum D, Jordan, Cheryl, Hayee, Bu'Hussain et al.·Inflammatory bowel diseases·2024

This study looked at people with inflammatory bowel disease (IBD) who experience fatigue and found that two behavior patterns predict worsening tiredness over time: all-or-nothing behavior (doing a lot of activity followed by needing extended rest) and catastrophic thinking (expecting the worst outcomes). These findings suggest that how patients think and behave may play an important role in their fatigue levels.

E2 ModerateCohortPEM not requiredCross-Sectional

An online survey among convalescents 5 months post SARS-CoV-2 infection in China.

Wang, Yalan, Liu, Maoshun, Guo, Yuanyuan et al.·Biosafety and health·2024

This study surveyed over 5,500 people in China about five months after they had COVID-19 to see what long-term health problems they experienced. The most common complaints were fatigue (tiredness), memory problems, post-exertional malaise (feeling much worse after physical activity), and brain fog. People with certain pre-existing conditions like heart disease, autoimmune diseases, or asthma were more likely to have moderate to severe symptoms.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Plasma and peritoneal fluid cytokine profiles in patient with Essure® implant: Towards a molecular signature?

Garnier, Lorna, Parant, François, Bulteau, Claire et al.·European journal of obstetrics, gynecology, and reproductive biology·2024

Researchers measured inflammation markers (cytokines) in blood and fluid from the abdomen in women with Essure implants, women with endometriosis, and healthy controls. They found that women with Essure implants had higher levels of two specific inflammation markers (MCP-1 and TNF-α) in their blood compared to controls. These same markers are known to be elevated in fibromyalgia and chronic fatigue syndrome, suggesting they might be relevant to understanding Essure-related symptoms.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Long-Term Impairment of Working Ability in Subjects under 60 Years of Age Hospitalised for COVID-19 at 2 Years of Follow-Up: A Cross-Sectional Study.

Frallonardo, Luisa, Ritacco, Annunziata Ilenia, Amendolara, Angela et al.·Viruses·2024

This study followed 322 people under age 60 who were hospitalized with COVID-19 and checked on them about 2 years later. Researchers found that 42% of these patients reported difficulty working compared to before they got sick, even though they had recovered from the acute infection. The study identified that women, people with diabetes, and those who needed oxygen during hospitalization were more likely to have lasting work problems.

Long COVID Overlap

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Comprehensive Assessment of Autonomic Nervous System Profiles in Postural Orthostatic Tachycardia Syndrome Among Syncope, Chronic Fatigue, and Post-COVID-19 Patients.

Babesia and Bartonella Species DNA in Blood and Enrichment Blood Cultures from People with Chronic Fatigue and Concurrent Neurological Symptoms.

Adverse effects of obesity on overall health, quality of life, and related physical health metrics: A cross-sectional and longitudinal study from the All of Us Research Program.

A Multidimensional Assessment of Sleep Disorders in Long COVID Using the Alliance Sleep Questionnaire.

The Physical and Mental Health of Post-9/11 Female and Male Veterans: Findings from the Comparative Health Assessment Interview Research Study.

Tracking Persistent Symptoms in Scotland (TraPSS): a longitudinal prospective cohort study of COVID-19 recovery after mild acute infection.

Unmasking the Long-Term Effects of COVID-19 With a Focus on Chronic Fatigue Syndrome: A Community-Based Study From India.

Putting the PASC Score to the Test: Clinical vs. Statistical Accuracy in Long COVID Diagnosis.

Does Prenatal SARS-CoV-2 Infection Exacerbate Postpartum Lower Urinary Tract Symptoms? A Multicenter Retrospective Cohort Study.

Cross-Sectional Study Evaluating the Role of Autonomic Nervous System Functional Diagnostics in Differentiating Post-Infectious Syndromes: Post-COVID Syndrome, Chronic Fatigue Syndrome, and Lyme Disease.

Cognitive functioning in patients with chronic fatigue syndrome: Slowed information processing or a deficit in attentional selectivity?

Three-Month Follow-Up of the Post-COVID Syndrome after Admission to a Specialised Post-COVID Centre-A Prospective Study Focusing on Mental Health with Patient Reported Outcome Measures (PROMs).

Data-independent LC-MS/MS analysis of ME/CFS plasma reveals a dysregulated coagulation system, endothelial dysfunction, downregulation of complement machinery.

Validity and diagnostic overlap of functional somatic syndrome diagnoses.

Perceived misdiagnosis of psychiatric conditions in autistic adults.

Hypothalamus Connectivity in Adolescent Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

All-or-Nothing Behavior and Catastrophic Thinking Predict Fatigue in Inflammatory Bowel Disease: A Prospective Cohort Study.

An online survey among convalescents 5 months post SARS-CoV-2 infection in China.

Plasma and peritoneal fluid cytokine profiles in patient with Essure® implant: Towards a molecular signature?

Long-Term Impairment of Working Ability in Subjects under 60 Years of Age Hospitalised for COVID-19 at 2 Years of Follow-Up: A Cross-Sectional Study.

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