Clinical trial Recruiting at 1 site Observational Ages 18 to 65

PEM: a starting point to understand ME/CFS

Official title: PEM, a Starting Point to Investigate and Understand ME/CFS

Run by University Medical Center Groningen · NCT07715838 · Data updated 2026-11-12

Researchers are studying post-exertional malaise to better understand ME/CFS in adults who report persistent fatigue and PEM.

Quick facts

Study typeObservational
Ages18 Years to 65 Years
SexAll
Enrollment100 (estimated)
SponsorUniversity Medical Center Groningen
Academic / other
Locations1 site (Groningen)
StatusRecruiting
StartedMay 1, 2024
Main results expectedOctober 31, 2026
Study endsJuly 31, 2027
Registry record updatedJuly 21, 2026
Trial IDNCT07715838 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults with ME/CFS who meet ICC or CCC criteria and have a self-reported history of persistent fatigue and PEM according to DSQ-2.

Probably not a fit

Patients without PEM or who do not meet ICC/CCC criteria may not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This observational study focuses on post-exertional malaise as the central symptom of ME/CFS. It aims to explore how minor physical or cognitive activity triggers responses across cardiovascular, metabolic, and molecular systems, using patient-reported questionnaires to characterize PEM. There is no active intervention; data will be collected from ME/CFS patients who meet ICC or CCC criteria and report PEM through the DSQ-2. The study seeks to clarify the relationship between PEM and broader ME/CFS symptoms to inform future diagnostic criteria and research directions. Participants provide informed consent and must be able to complete all study procedures.

Why it matters

Potential benefit: If successful, findings could improve understanding of PEM in ME/CFS and guide future diagnostic approaches and research.

How similar studies have gone: Prior research has shown PEM to be a central feature in ME/CFS, but comprehensive, standardized PEM-focused data remain limited, making this approach both informed and somewhat novel.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Willing and be able to complete all study procedures
* Able to provide informed consent

Additional inclusion criteria for ME/CFS patients

* ME/CFS patients have to meet the criteria of the ICC OR CCC.
* A self-reported illness narrative of the development of persistent fatigue and post-exertional malaise according to the DSQ-2. The persistent fatigue may have an acute onset or become progressively worse over 6 months.

Exclusion Criteria:

* Use of immune-modulating drugs in the past 3 months.
* A serious medical condition that may explain symptoms similar to ME/CFS, such as cancer, coronary artery disease, uncontrolled diabetes, chronic infection (hepatitis B and C, tuberculosis, HIV), inflammatory diseases, autoimmune diseases (e.g. such as rheumatoid arthritis, lupus or polymyositis), severe COPD or other severe persistent respiratory disease, severe anemia, renal failure, Addison's or Cushing's disease or severe neurological disease (such as Parkinson's disease).
* History of head injury with loss of consciousness or amnesia lasting greater than a few seconds within last five years or lasting greater than 5 minutes at any point during their lifetime. Persons with medical record evidence of post-concussive symptoms lasting more than six months are also excluded.
* Suspected, probable, or confirmed Lyme disease
* Current or substance use disorder within last 5 years
* A mood disorder or other psychiatric diagnosis prior to a diagnosis of ME/CFS.
* Pregnant, actively seeking to become or breastfeeding in the past 12 months.
* BMI \>35.
* having cognitive or communication problems which reduces the capacity to understand instructions.
* planned a change in medication during the testing period.
* Use of medication that affects the blood pressure (e.g. Beta-blockers, fludrocortisone, vasoconstrictors).
* Participation in a clinical protocol (e.g. anti-inflammatory drug intervention study) which includes an intervention that may affect the results of the current study.
* Claustrophobia
* Current (within 1 week) use of prescription or over-the-counter medications, herbal supplements, or nutraceuticals that may influence brain excitability that the potential participant is either unwilling or clinically unable to safely wean off for the duration of the period of the visits. The possibility for a potential participant to be weaned off medication will be cooperatively determined by both the clinical investigative team and personal physicians. Examples of medications that influence brain excitability include tricyclic antidepressants, hypnotic, antiepileptic, antipsychotic medication, stimulants, antihistamines, muscle relaxants, dopaminergic medications, and sleep medications.
* Use of B12 high dosage injections
* Being colorblind

Additional exclusion criteria for control subjects:

* performing high intensity or moderate intensity activities more than 30 minutes per week
* substantial fatigue as determined using MFIS fatigue questionnaire \>30

Where it's running

  • UMC Groningen
    Groningen, Netherlands
    Recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.