ME/CFS Evidence Browser — Classified Studies on Myalgic Encephalomyelitis

1821–1840 of 6,209 studies

E2 ModerateCohortPEM not requiredObservational

Hospital Records of Pain, Fatigue, or Circulatory Symptoms in Girls Exposed to Human Papillomavirus Vaccination: Cohort, Self-Controlled Case Series, and Population Time Trend Studies.

Thomsen, Reimar Wernich, Öztürk, Buket, Pedersen, Lars et al.·American journal of epidemiology·2020

This large Danish study looked at whether the HPV vaccine (which prevents cervical cancer) was linked to symptoms like pain, fatigue, or heart problems in girls. Researchers compared vaccinated and unvaccinated girls over 14 years and found no increase in hospital visits for these symptoms in vaccinated girls. The symptoms they tracked increased over time in both vaccinated and unvaccinated children, suggesting other factors were responsible.

E2 ModerateCohortPEM not requiredObservational

Association between quadrivalent human papillomavirus vaccination and selected syndromes with autonomic dysfunction in Danish females: population based, self-controlled, case series analysis.

Hviid, Anders, Thorsen, Nicklas M, Valentiner-Branth, Palle et al.·BMJ (Clinical research ed.)·2020

This study examined whether the HPV vaccine (used to prevent cervical cancer) was linked to ME/CFS, complex regional pain syndrome, or POTS in over 1.3 million Danish girls and women. Researchers found no evidence that the vaccine caused these conditions—the rates of these illnesses were similar whether or not girls received the vaccine.

Autonomic Nervous System

E2 ModerateBehavioralPEM not requiredCase-Control

A MAPP Network Case-control Study of Urological Chronic Pelvic Pain Compared With Nonurological Pain Conditions.

Afari, Niloofar, Buchwald, Dedra, Clauw, Daniel et al.·The Clinical journal of pain·2020

This study compared people with chronic pelvic pain conditions to people with other widespread chronic pain conditions like fibromyalgia and chronic fatigue syndrome, as well as healthy volunteers. Researchers found that while these conditions affect different parts of the body, people with all these conditions share similar emotional and psychological challenges—like anxiety, depression, and stress—suggesting they may share common underlying causes. The study suggests that treating these conditions effectively may require addressing both physical pain and psychological factors together.

E2 ModerateCohortPEM not requiredCross-Sectional

Metabolic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Not Due to Anti-mitochondrial Antibodies.

Nilsson, Isabell, Palmer, Jeremy, Apostolou, Eirini et al.·Frontiers in medicine·2020

Researchers tested whether ME/CFS patients have immune system antibodies that attack their mitochondria (the energy-producing parts of cells), similar to what happens in a different disease called primary biliary cholangitis. They found that ME/CFS patients almost never have these specific antibodies, while patients with the other disease have them consistently. This suggests that the energy problems seen in ME/CFS are caused by something other than the immune system attacking mitochondria.

Energy Metabolism

E2 ModerateCohortPEM not requiredCross-Sectional

Pain in adolescent chronic fatigue following Epstein-Barr virus infection.

Brodwall, Elias Myrstad, Pedersen, Maria, Asprusten, Tarjei Tørre et al.·Scandinavian journal of pain·2020

This study looked at pain symptoms in teenagers who developed chronic fatigue after a common virus infection (Epstein-Barr virus). Researchers compared teenagers who had the virus and became fatigued, those who had the virus but did not become fatigued, and healthy teenagers without the virus. They found that the fatigued group reported significantly more pain symptoms and that the amount of pain they experienced was strongly linked to their quality of life.

Pain and Sensitization

E2 ModerateCohortPEM not requiredObservational

Parasympathetic activity is reduced during slow-wave sleep, but not resting wakefulness, in patients with chronic fatigue syndrome.

Fatt, Scott J, Beilharz, Jessica E, Joubert, Michael et al.·Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine·2020

This study found that people with ME/CFS have reduced calming nervous system activity during deep sleep, compared to healthy people. This overactive state during sleep—even when the brain should be resting—is linked to poor sleep quality and feeling unwell. The findings suggest that the body's inability to fully relax during sleep may be a key problem in ME/CFS.

Autonomic Nervous System

E2 ModeratePEM not requiredRegistry-Resource

Exploring the concept of vigor and dys-vigor in men of 50-65 years: effects of Robuvit®.

Ledda, Andrea, Hosoi, Morio, Cesarone, Maria R et al.·Panminerva medica·2020

This small study tested whether a supplement called Robuvit® (made from oak wood extract) could help middle-aged men feel more energetic and less tired. Forty men aged 50-65 who felt exhausted took either standard lifestyle advice alone or the same advice plus the supplement for 4 weeks. Both groups improved, but the men taking Robuvit® reported significantly better energy levels and had lower markers of cellular stress in their blood.

E2 ModerateBehavioralPEM not requiredCross-Sectional

Prevalence of functional somatic syndromes and bodily distress syndrome in the Danish population: the DanFunD study.

Petersen, Marie Weinreich, Schröder, Andreas, Jørgensen, Torben et al.·Scandinavian journal of public health·2020

This study looked at how common six functional somatic syndromes—including ME/CFS, fibromyalgia, and IBS—are in the general Danish population. Researchers surveyed nearly 10,000 adults and found that about 16% had at least one of these conditions, with ME/CFS being the most common at 8.6%. People with these syndromes reported poor health, difficulty with daily activities, and higher rates of depression and anxiety, especially when they had multiple conditions.

E2 ModerateCohortPEM not requiredObservational

A cluster analysis of serious adverse event reports after human papillomavirus (HPV) vaccination in Danish girls and young women, September 2009 to August 2017.

Ward, Daniel, Thorsen, Nicklas Myrthue, Frisch, Morten et al.·Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin·2019

This study examined adverse event reports submitted to Danish health authorities after HPV vaccination between 2009 and 2017. Researchers found that fatigue, dizziness, and headache were common symptoms reported, and noticed that some clusters of reports—particularly those mentioning cognitive problems and sleep issues—were submitted during periods of increased media coverage about vaccine safety concerns.

Autonomic Nervous SystemCognitive Impairment

E2 ModerateDiagnosticPEM not requiredLongitudinal

A Validated Scale for Assessing the Severity of Acute Infectious Mononucleosis.

Katz, Ben Z, Reuter, Caroline, Lupovitch, Yair et al.·The Journal of pediatrics·2019

Researchers created a simple scoring system to measure how severe a case of infectious mononucleosis (mono) is when someone first gets sick. They found that students with higher severity scores were more likely to need hospitalization or steroid treatment, and importantly, those with higher scores were also more likely to develop ME/CFS within 6 months after their mono infection.

E2 ModerateReviewPEM not requiredMeta-Analysis

Self-Compassion and Adherence in Five Medical Samples: the Role of Stress.

Sirois, Fuschia M, Hirsch, Jameson K·Mindfulness·2019

This study looked at whether being kind and compassionate to yourself helps people with chronic illnesses—including ME/CFS—stick to their medical treatments. Researchers surveyed 709 patients across five different conditions and found that people who naturally practice self-compassion do tend to follow their treatment plans better. They also discovered that part of this benefit happens because self-compassion helps reduce stress.

E2 ModerateCohortPEM unclearObservational

MtDNA population variation in Myalgic encephalomyelitis/Chronic fatigue syndrome in two populations: a study of mildly deleterious variants.

Venter, Marianne, Tomas, Cara, Pienaar, Ilse S et al.·Scientific reports·2019

This study looked at mitochondrial DNA (the genetic material in the energy-producing parts of our cells) in people with ME/CFS to see if differences in this DNA might help explain the condition. Researchers compared DNA samples from ME/CFS patients in the UK and South Africa to look for variations. Interestingly, they found that ME/CFS patients were less likely to have certain common genetic variations that most people carry, but they did not find any confirmed disease-causing mutations.

Energy Metabolism

E2 ModerateCohortPEM requiredCross-Sectional

Deconstructing post-exertional malaise: An exploratory factor analysis.

McManimen, Stephanie L, Sunnquist, Madison L, Jason, Leonard A·Journal of health psychology·2019

This study looked at post-exertional malaise (PEM)—the worsening of symptoms that happens after physical activity in ME/CFS—to understand whether it is one unified experience or two different types. The researchers found that PEM actually consists of two separate experiences: a whole-body fatigue and a muscle-specific fatigue. This suggests that PEM is more complex than previously thought and may need to be understood as having distinct components.

Post-Exertional Malaise

E2 ModerateCohortPEM not requiredCross-Sectional

Clinical symptoms and markers of disease mechanisms in adolescent chronic fatigue following Epstein-Barr virus infection: An exploratory cross-sectional study.

Kristiansen, Miriam Skjerven, Stabursvik, Julie, O'Leary, Elise Catriona et al.·Brain, behavior, and immunity·2019

This study looked at adolescents who had Epstein-Barr virus (EBV) infection and tracked whether they developed chronic fatigue 6 months later. Researchers found that those with ongoing fatigue had more symptoms overall, but blood tests and heart-monitoring showed only small differences compared to those who recovered—mainly slightly higher inflammation markers and changes in nervous system activity. The study suggests that post-EBV fatigue in teenagers involves subtle changes in the body's stress and immune systems, even though the virus itself had cleared.

Immune System

E2 ModerateCohortPEM not requiredCross-Sectional

Performance of the American College of Rheumatology 2016 criteria for fibromyalgia in a referral care setting.

Ahmed, Sakir, Aggarwal, Amita, Lawrence, Able·Rheumatology international·2019

This study tested how well the 2016 fibromyalgia diagnostic criteria work in hospital specialty clinics, where patients often have multiple conditions. Researchers found that the newer criteria identified some patients that an experienced doctor using older criteria would not have diagnosed, and these patients were more likely to also have other conditions like restless leg syndrome, PTSD, or chronic fatigue syndrome. The 2016 criteria performed reasonably well, but doctors should be aware they may be catching patients with overlapping conditions rather than pure fibromyalgia.

Diagnostics

E2 ModerateCohortPEM not requiredCross-Sectional

Prevalence and characteristics of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) in Poland: a cross-sectional study.

Słomko, Joanna, Newton, Julia L, Kujawski, Sławomir et al.·BMJ open·2019

Researchers in Poland studied 1,400 people who reported feeling very tired to understand how common ME/CFS really is. They found that 69 people actually had ME/CFS based on standard diagnostic criteria. These patients experienced severe fatigue that lasted years, had trouble staying awake during the day, problems with dizziness when standing up, anxiety, and depression—all of which seriously affected their quality of life.

Sleep

E2 ModerateCohortPEM requiredObservational

Post-Exertional Malaise Is Associated with Hypermetabolism, Hypoacetylation and Purine Metabolism Deregulation in ME/CFS Cases.

McGregor, Neil R, Armstrong, Christopher W, Lewis, Donald P et al.·Diagnostics (Basel, Switzerland)·2019

This study looked at what happens in the body during post-exertional malaise (PEM)—the exhaustion and worsening of symptoms that ME/CFS patients experience after physical or mental activity. Researchers measured chemical changes in blood and urine over 7 days in 35 ME/CFS patients who reported PEM and compared them to healthy controls. They found that during PEM, the body shows signs of increased metabolism (burning energy faster), low levels of a molecule called hypoxanthine, and problems with how cells use and process energy, along with evidence that the body is breaking down muscle protein.

Post-Exertional Malaise

E2 ModerateCohortPEM requiredCross-Sectional

Systemic exertion intolerance disease/chronic fatigue syndrome is common in sleep centre patients with hypersomnolence: A retrospective pilot study.

Maness, Caroline, Saini, Prabhjyot, Bliwise, Donald L et al.·Journal of sleep research·2019

This study looked at people visiting sleep clinics who reported excessive daytime sleepiness and found that 21% of them also met criteria for ME/CFS (systemic exertion intolerance disease). People with both conditions reported more severe fatigue and were less likely to benefit from standard wake-promoting medications compared to those with only sleep disorders. The findings suggest that ME/CFS frequently occurs alongside sleep disorders and may make treatment more difficult.

Post-Exertional Malaise

E2 ModerateCohortPEM unclearCross-Sectional

Searching for Serum Antibodies to Neuronal Proteins in Patients With Myalgic Encephalopathy/Chronic Fatigue Syndrome.

Giannoccaro, Maria Pia, Cossins, Judith, Sørland, Kari et al.·Clinical therapeutics·2019

Researchers tested blood samples from 50 ME/CFS patients and 50 healthy people to see if ME/CFS patients had unusual antibodies (immune proteins) that attack nerve cells. While a small number of both patients and healthy people had some immune activity toward nerve proteins, only one ME/CFS patient had a specific antibody that could be clearly identified. Interestingly, the patients who did have these antibodies tended to have more severe symptoms and had become ill more recently.

Immune System

E2 ModerateCohortPEM unclearObservational

Relationship Between Exercise-induced Oxidative Stress Changes and Parasympathetic Activity in Chronic Fatigue Syndrome: An Observational Study in Patients and Healthy Subjects.

Polli, Andrea, Van Oosterwijck, Jessica, Nijs, Jo et al.·Clinical therapeutics·2019

This study looked at whether oxidative stress (cellular damage from normal metabolism) is related to pain in ME/CFS patients, and how it connects to the vagus nerve, which helps control the body's relaxation response. Researchers had ME/CFS patients and healthy people do a mild exercise test and measured their pain, oxidative stress levels, and nerve activity before and after. They found that oxidative stress was linked to pain in ME/CFS patients, but unlike healthy people, ME/CFS patients didn't show improvements in pain or oxidative stress after exercise.

Pain and SensitizationAutonomic Nervous System

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Evidence browser

Hospital Records of Pain, Fatigue, or Circulatory Symptoms in Girls Exposed to Human Papillomavirus Vaccination: Cohort, Self-Controlled Case Series, and Population Time Trend Studies.

Association between quadrivalent human papillomavirus vaccination and selected syndromes with autonomic dysfunction in Danish females: population based, self-controlled, case series analysis.

A MAPP Network Case-control Study of Urological Chronic Pelvic Pain Compared With Nonurological Pain Conditions.

Metabolic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Not Due to Anti-mitochondrial Antibodies.

Pain in adolescent chronic fatigue following Epstein-Barr virus infection.

Parasympathetic activity is reduced during slow-wave sleep, but not resting wakefulness, in patients with chronic fatigue syndrome.

Exploring the concept of vigor and dys-vigor in men of 50-65 years: effects of Robuvit®.

Prevalence of functional somatic syndromes and bodily distress syndrome in the Danish population: the DanFunD study.

A cluster analysis of serious adverse event reports after human papillomavirus (HPV) vaccination in Danish girls and young women, September 2009 to August 2017.

A Validated Scale for Assessing the Severity of Acute Infectious Mononucleosis.

Self-Compassion and Adherence in Five Medical Samples: the Role of Stress.

MtDNA population variation in Myalgic encephalomyelitis/Chronic fatigue syndrome in two populations: a study of mildly deleterious variants.

Deconstructing post-exertional malaise: An exploratory factor analysis.

Clinical symptoms and markers of disease mechanisms in adolescent chronic fatigue following Epstein-Barr virus infection: An exploratory cross-sectional study.

Performance of the American College of Rheumatology 2016 criteria for fibromyalgia in a referral care setting.

Prevalence and characteristics of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) in Poland: a cross-sectional study.

Post-Exertional Malaise Is Associated with Hypermetabolism, Hypoacetylation and Purine Metabolism Deregulation in ME/CFS Cases.

Systemic exertion intolerance disease/chronic fatigue syndrome is common in sleep centre patients with hypersomnolence: A retrospective pilot study.

Searching for Serum Antibodies to Neuronal Proteins in Patients With Myalgic Encephalopathy/Chronic Fatigue Syndrome.

Relationship Between Exercise-induced Oxidative Stress Changes and Parasympathetic Activity in Chronic Fatigue Syndrome: An Observational Study in Patients and Healthy Subjects.

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