ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

41–60 of 247 studies

E2 ModerateBehavioralPEM not requiredObservational

Prevalence of Bodily Distress Syndrome and Prediction of Patient Outcomes: Cohort Study of 3762 Individuals With Persistent Pain.

Landmark, Live, Sunde, Hans Fredrik, Fors, Egil A et al.·European journal of pain (London, England)·2026

This study looked at how multiple physical symptoms often occur together in people with chronic pain, using a framework called Bodily Distress Syndrome (BDS). Among 3,762 people attending a specialized pain clinic, 92.5% showed moderate to severe BDS, and those with BDS experienced more severe symptoms and psychological stress. After one year, people with BDS improved less and reported less benefit from treatment compared to those without BDS.

Pain and Sensitization

E2 ModerateCohortPEM not requiredLongitudinal

Long COVID longitudinal symptoms burden clusters within a national community-based cohort.

Shen, Yanhan, Shahn, Zach, Robertson, McKaylee M et al.·BMC infectious diseases·2026

This study followed over 500 people with long COVID for up to a year, tracking their symptoms over time. Researchers identified three groups based on symptom burden: one with persistent severe symptoms (including fatigue, brain fog, post-exertional malaise, and pain), one with moderate symptoms that improved, and one with minimal symptoms. The findings are preliminary and based on self-reported data, so the stability and generalisability of these groups to other long COVID populations remain to be confirmed.

Pain and SensitizationSleepAutonomic Nervous SystemCognitive Impairment

E2 ModerateBehavioralPEM not requiredCross-Sectional

Disentangling comorbidity: symptom dimensions of internalizing and functional disorders in a large general population sample.

Saini, Urvi, Aggen, Steven H, Oldehinkel, Albertine J et al.·BMC psychiatry·2026

This study looked at how symptoms of depression, anxiety, ME/CFS, fibromyalgia, and irritable bowel syndrome overlap in over 100,000 people. Researchers found that these conditions share common symptoms like fatigue, sleep problems, and difficulty concentrating—which they call 'general malaise'—rather than being completely separate diseases. Understanding these shared symptoms may help explain why people often have multiple conditions at the same time.

Pain and SensitizationCognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Clinical Importance of Central Sensitization and Neuropathic Pain in The Treatment and Follow-Up of Patients with Psoriasis and Psoriatic Arthritis.

Koca, Tuba Tülay, Göğebakan, Hasan, Nazik, Hülya et al.·Indian journal of dermatology·2026

This study looked at whether people with skin and joint conditions (psoriasis and psoriatic arthritis) experience unusual pain processing in their nervous system, similar to what happens in conditions like fibromyalgia. Researchers found that many patients with these conditions had signs of nervous system sensitization and neuropathic pain (nerve-related pain). The more active their disease was, the more likely they were to have these pain processing problems.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCross-Sectional

Altered Pain Perception and Modulation in Individuals With Post-COVID-Condition: Insights From Quantitative Sensory Testing.

Lange, Hannah, Reichert, Julian, Vock, Stephanie et al.·European journal of pain (London, England)·2026

This study tested how people with long COVID perceive and respond to pain compared to healthy people. Researchers applied pressure to participants' legs and measured when they first felt pain and when pain became unbearable. People with long COVID felt pain at lower pressure levels and their pain got worse more quickly than healthy controls, suggesting their nervous systems process pain differently.

Pain and Sensitization

E2 ModerateBehavioralPEM not requiredCross-Sectional

Network structure of functional somatic symptoms.

Litzenburger, Alexandra, Rothacher, Yannick, Hanusch, Kay-Uwe et al.·Journal of psychosomatic research·2025

This study looked at how symptoms cluster together in people with functional somatic syndromes (like ME/CFS, fibromyalgia, and others). Researchers surveyed over 3,000 young adults and used network analysis to map which symptoms tend to appear together. They found that fatigue and depression are particularly important symptoms that connect different symptom groups, and identified ten distinct clusters of related symptoms.

Pain and SensitizationCognitive Impairment

E2 ModerateCohortPEM requiredCross-Sectional

The association of fatigue and pain with cognitive test performance in patients with myalgic encephalomyelitis/chronic fatigue syndrome.

Oosterman, Joukje M, van der Schaaf, Marieke, de Kleijn, Willemien P E et al.·Journal of psychosomatic research·2025

This study looked at how fatigue and pain affect thinking and memory problems in people with ME/CFS. Researchers tested 1,375 patients on tasks like reaction time and attention, and found that both fatigue severity and pain severity were linked to worse cognitive performance. The effects were stronger in older patients, suggesting that age may play a role in how much fatigue and pain impact thinking abilities.

Pain and SensitizationCognitive Impairment

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 requiredCross-Sectional

Exploratory study on autoantibodies to arginine-rich human peptides mimicking Epstein-Barr virus in women with post-COVID and myalgic encephalomyelitis/chronic fatigue syndrome.

Hoheisel, Friederike, Fleischer, Kathrin Maria, Rubarth, Kerstin et al.·Frontiers in immunology·2025

This study looked for certain antibodies in the blood of women with post-COVID and ME/CFS that might mistakenly attack the body's own proteins. The researchers found that patients with these conditions had more of these problematic antibodies than healthy people, and these antibodies were linked to common ME/CFS symptoms like fatigue, brain fog, pain, and autonomic problems. The results suggest that a virus (EBV) may trigger the immune system to attack human proteins that look similar to viral proteins.

Pain and SensitizationAutonomic Nervous SystemCognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Identifying commonalities and differences between EHR representations of PASC and ME/CFS in the RECOVER EHR cohort.

Powers, John P, McIntee, Tomas J, Bhatia, Abhishek et al.·Communications medicine·2025

Researchers compared medical records from millions of patients to see how Long COVID (PASC) and ME/CFS are similar and different. They found that both conditions share common symptoms like fatigue, breathing difficulties, and trouble concentrating, but Long COVID tends to have more heart and lung problems, while ME/CFS more often involves pain and sleep issues. These similarities suggest that some treatment approaches might help both conditions.

Pain and SensitizationSleepCognitive Impairment

E2 ModerateCohortPEM not requiredObservational

Nonpelvic comorbid symptoms of 45 patients with pain of pelvic venous origin, before and after treatment.

Smith, Steven J, Smith, B Holly, Sichlau, Michael J et al.·Phlebology·2025

This study looked at 45 women with chronic pelvic pain caused by abnormal blood pooling in pelvic veins. These patients experienced many symptoms beyond pelvic pain—including brain fog, fatigue, migraines, constipation, and anxiety. After receiving a catheter-based procedure to fix the blood pooling, most of these systemic symptoms improved significantly (by 50% or more).

Pain and SensitizationAutonomic Nervous SystemCognitive Impairment

E2 ModerateCohortPEM not requiredCross-Sectional

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Impact on Quality of Life (QoL) of Persons with ME/CFS.

Muirhead, Nina L, Vyas, Jui, Ephgrave, Rachel et al.·Medicina (Kaunas, Lithuania)·2024

This study surveyed 876 people with ME/CFS from 26 countries to understand how the condition affects their daily lives. People with ME/CFS reported very poor quality of life, with an average health rating of 36 out of 100. The most common problems were difficulty doing everyday activities (97%), pain (92%), and trouble with movement (83%).

Pain and Sensitization

E2 ModerateCohortPEM unclearObservational

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 ModerateCohortPEM not requiredCross-Sectional

Presence of endometriosis and chronic overlapping pain conditions negatively impacts the pain experience in women with chronic pelvic-abdominal pain: A cross-sectional survey.

Bartley, Emily J, Alappattu, Meryl J, Manko, Kelsey et al.·Women's health (London, England)·2024

This study looked at 525 women with chronic pelvic and abdominal pain to understand how endometriosis (a condition where tissue grows outside the uterus) affects their pain experience. Women with endometriosis reported more severe pain, greater interference with daily life, and were more likely to have other overlapping pain conditions like fibromyalgia and chronic fatigue syndrome. The more pain conditions a woman had, the worse her overall pain burden became, regardless of whether she had endometriosis.

Pain and Sensitization

E2 ModerateCohortPEM requiredCross-Sectional

Dry eye symptoms and signs in United States Gulf War era veterans with myalgic encephalomyelitis/chronic fatigue syndrome.

Sanchez, Victor, Kim, Colin K, Locatelli, Elyana V T et al.·Clinical & experimental ophthalmology·2024

Researchers studied eye dryness and discomfort in Gulf War veterans with ME/CFS and compared them to veterans without the condition. They found that people with ME/CFS reported significantly more eye pain and dryness symptoms, even though physical examination of their eyes showed similar amounts of tear production and surface damage as the control group. This suggests that the eye pain experienced by ME/CFS patients may come from causes beyond just dry eyes.

Pain and Sensitization

E2 ModerateBehavioralPEM not requiredCross-Sectional

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 ModerateCohortPEM required

Brainstem volume changes in myalgic encephalomyelitis/chronic fatigue syndrome and long COVID patients.

Thapaliya, Kiran, Marshall-Gradisnik, Sonya, Barth, Markus et al.·Frontiers in neuroscience·2023

Researchers used advanced MRI scans to examine a part of the brain called the brainstem in patients with ME/CFS and long COVID, comparing them to healthy people. They found that both patient groups had larger volumes in certain brainstem areas compared to healthy controls. The size of specific brainstem regions also correlated with symptom severity, particularly pain and breathing difficulties.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCross-Sectional

Effect of Central Sensitization in Patients with Familial Mediterranean Fever, Axial Spondyloarthritis, and Both Diseases.

Kaya, Mehmet Nur, Kılıç, Özlem, Doğan, Abdullah et al.·Cureus·2023

This study looked at whether three groups of patients—those with familial Mediterranean fever (FMF), a type of spinal arthritis (axSpA), or both conditions—experience heightened pain sensitivity and related symptoms like fatigue and fibromyalgia compared to healthy people. Researchers used a questionnaire to measure 'central sensitization,' which is when the nervous system amplifies pain signals. They found that patients with these conditions did score higher on pain sensitivity measures than healthy controls, and chronic fatigue was particularly common in the FMF group.

Pain and Sensitization

E2 ModerateCohortPEM not requiredCase-Control

The Impact of Micro RNA-320a Serum Level on Severity of Symptoms and Cerebral Processing of Pain in Patients with Fibromyalgia.

Hussein, Mona, Fathy, Wael, Abdelaleem, Enas A et al.·Pain medicine (Malden, Mass.)·2022

Researchers measured a molecule called miR-320a in the blood of people with fibromyalgia and compared it to healthy people. They found that fibromyalgia patients had higher levels of this molecule, and those with higher levels tended to have worse symptoms like pain, fatigue, sleep problems, and depression. However, this molecule did not appear to affect how the brain processes pain signals.

Pain and SensitizationSleep

E2 ModerateCohortPEM not requiredObservational

The incidence and characteristics of chronic pain and fatigue after 12 months later admitting with COVID-19; The Post- COVID 19 syndrome.

Janbazi, Lobaneh, Kazemian, Alireza, Mansouri, Kourosh et al.·American journal of physical medicine & rehabilitation·2022

Researchers followed 157 people who were hospitalized with COVID-19 and checked on them 12 months later. They found that about 27% still had chronic fatigue and muscle weakness, and about 15% experienced chronic pain, mostly in the lower back and legs. Women were more likely than men to report these symptoms, and many patients were only using pain medications rather than receiving rehabilitation or mental health support.

Pain and Sensitization

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Prevalence of Bodily Distress Syndrome and Prediction of Patient Outcomes: Cohort Study of 3762 Individuals With Persistent Pain.

Long COVID longitudinal symptoms burden clusters within a national community-based cohort.

Disentangling comorbidity: symptom dimensions of internalizing and functional disorders in a large general population sample.

Clinical Importance of Central Sensitization and Neuropathic Pain in The Treatment and Follow-Up of Patients with Psoriasis and Psoriatic Arthritis.

Altered Pain Perception and Modulation in Individuals With Post-COVID-Condition: Insights From Quantitative Sensory Testing.

Network structure of functional somatic symptoms.

The association of fatigue and pain with cognitive test performance in patients with myalgic encephalomyelitis/chronic fatigue syndrome.

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.

Exploratory study on autoantibodies to arginine-rich human peptides mimicking Epstein-Barr virus in women with post-COVID and myalgic encephalomyelitis/chronic fatigue syndrome.

Identifying commonalities and differences between EHR representations of PASC and ME/CFS in the RECOVER EHR cohort.

Nonpelvic comorbid symptoms of 45 patients with pain of pelvic venous origin, before and after treatment.

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Impact on Quality of Life (QoL) of Persons with ME/CFS.

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

Presence of endometriosis and chronic overlapping pain conditions negatively impacts the pain experience in women with chronic pelvic-abdominal pain: A cross-sectional survey.

Dry eye symptoms and signs in United States Gulf War era veterans with myalgic encephalomyelitis/chronic fatigue syndrome.

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

Brainstem volume changes in myalgic encephalomyelitis/chronic fatigue syndrome and long COVID patients.

Effect of Central Sensitization in Patients with Familial Mediterranean Fever, Axial Spondyloarthritis, and Both Diseases.

The Impact of Micro RNA-320a Serum Level on Severity of Symptoms and Cerebral Processing of Pain in Patients with Fibromyalgia.

The incidence and characteristics of chronic pain and fatigue after 12 months later admitting with COVID-19; The Post- COVID 19 syndrome.

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