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Fatigue Syndrome, ChronicNCT03675087

Assessment of Exercise Response in Chronic Fatigue Syndrome / Myalgic Encephalomyelitis.

An observational study of Fatigue Syndrome, Chronic, run by Escuela Universitaria de Fisioterapia de la Once at 1 site in Spain.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
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Trial summary

This study evaluates the correlation between the 6-min walking test (6MWT) with gases measurement, and the peak cardiopulmonary exercise testing (CPET) using incremental cycling with gases and workload measurement, in order to determine if the 6MWT detects impairment in exercise tolerance and if it avoids the… Read more about this study

Who is it for?
Ages 18 to 65 years
Conditions the study is for
Fatigue Syndrome, Chronic
How many people
22 participants
Where
1 siteSpain
Study dates
27 Feb 2019to Dec 2025
Phase
Observational
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 65 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Study population: Chronic Fatigue Syndrome/ Myalgic Encephalomyelitis affected and derived by their specialist in internal medicine from Hospital Universitario La Paz or by the Asociación de Afectados por el Síndrome de Fatiga Crónica y el Síndrome de Sensibilidad Química Múltiple de la Comunidad de Madrid, to the Escuela Universitaria de Fisioterapia de la ONCE and to the Department of Functional Tests of the Pneumology Service of the Hospital Universitario La Paz, Madrid (Spain) from October 1st, 2018 to July 1st, 2025 and that fulfill the inclusion criteria and do not present any exclusion criteria.

Who may be able to join

  • To be diagnosed by a medical specialist in internal medicine with experience in this disease. For this, the participant must fulfill with the diagnostic criteria of CFS/ME, following the recommended criteria for the diagnosis of 2015.
  • Prior signing of the informed consent.

Who cannot join

  • Present any of the diagnoses considered excluding of the CFS/ME, according to the international criteria recommended for clinical diagnosis and the selection of subjects for research:
  • Primary psychiatric disorders
  • Somatoform disorders
  • or Substance abuse
  • Present any of the absolute or relative contraindications, to perform exercise tests, described in previous investigations:
  • Decompensated heart failure
Show all 32Show fewer
  • Acute myocardial infarction (less than 3 days)
  • Syncope
  • Unstable angina
  • Cardiac arrhythmia poorly controlled
  • Endocarditis, myocarditis or acute pericarditis
  • Acute pulmonary edema
  • Moderate or severe cardiac valvular stenosis
  • Suspected dissection or dissecting aortic aneurysm
  • O2 saturation at rest less than 85%
  • Acute renal failure
  • Untreated thyrotoxicosis
  • Acute infection
  • Uncontrolled hypertension (greater than 200-120 mmHg)
  • Hypertrophic obstructive cardiomyopathy
  • High-grade atrioventricular block
  • Significant pulmonary arterial hypertension
  • Advanced or risky pregnancy
  • Significant diselectrolithmia
  • Severe symptomatic aortic stenosis
  • Severe anemia
  • Pulmonary embolism
  • Acute thrombophlebitis
  • Traumatologic, orthopedic or neurological pathology that does not allow to walk or cycling.
  • Psychic incapacity to understand the instructions of the tests.
  • Present comorbidity of Multiple Chemical Sensitivity Syndrome.
  • Have performed the peak incremental CPET in the last 3 years.

Trial locations and contacts

1 site in 1 country. Contact the study team or a site near you to ask about taking part.

Susana García-Juez, Lecturer contact

915894500 ext. 4496

sgj@once.es

Irene Rodríguez-Andonaegui, Lecturer contact

915894500 ext. 4389

irra@once.es

Spain1 site, 1 recruiting

  • Escuela Universitaria de Fisioterapia de la ONCE

    Madrid, 28034

    Susana García-Juez, Lecturer, +0034915894500 ext. 4496, sgj@once.es

    Irene Rodríguez-Andonaegui, Lecturer, +0034915894500 ext. 4389, irra@once.es

    Recruiting

Other trials in Spain

About this study

This study evaluates the correlation between the 6-min walking test (6MWT) with gases measurement, and the peak cardiopulmonary exercise testing (CPET) using incremental cycling with gases and workload measurement, in order to determine if the 6MWT detects impairment in exercise tolerance and if it avoids the post-exertional malaise that the peak CPET causes on decreasing levels of physical activity, in participants affected by chronic fatigue syndrome/ myalgic encephalomyelitis (CFS/ME).

Physical activity level at baseline (usual activity, the parcipant will not be given any directions) will be recorded during 7 days, 24 hours/day. Afterwards, the 6MWT will be performed. After this test, the physical activity level will be collected again during 7 days, 24 hours/day. Peak CPET will be carried out 14 days after 6MWT to make sure that the basal levels are recovered, and finally, physical activity level will be collected again during 7 days, 24 hours/day.

Read the detailed description

Chronic fatigue syndrome/ myalgic encephalomyelitis presents with a significant deterioration of functional capacity, which seriously affects the quality of life. The peak or maximal incremental CPET is considered valid for the evaluation of exercise tolerance of those affected by CFS/ME, but its performance causes worsening of its symptomatology, decreasing its physical activity level after the test. It has not been verified whether the 6MWT (submaximal exercise test) with gases measurement is able to assess the exercise tolerance of those affected by SFC/EM without increasing their symptoms. So far, only the correlation between another submaximal test and a peak CPET in two different groups of participants have been analyzed and proven, which it makes necessary to check adequately whether there is a correlation by performing both tests on the same participants. In addition, it is necessary to compare the degree of worsening in physical activity level that both tests produce in participants, because they have not been objectively evaluated in any previous study. It could be useful to have a more innocuous and simple test for the assessment of exercise tolerance in CFS/ME in clinical practice, in order to evaluate the benefits of treatments like rehabilitation programs. 6MWT could respond to these characteristics because it reaches an identical value in peak VO2 than in the peak CPET in other pathologies and it generates less physical stress.

This research will be developed with the utmost respect for individual human rights, according to the postulates accepted internationally by the United Nations and the European Commission (Helsinki Act of 1964 and the Oviedo Convention of 1997) and Regulation (EU) 2016/679 of the European Parliament and the Council of April 27, 2016 on Data Protection (RGPD).

Participation in this study is entirely voluntary and does not imply any risk to health. Participants are entitled to refuse to participate or to leave the study at any time they choose.

All information will be treated confidentially. If it is decided to publish the results of the study, in these publications will not include individual data or the names of the participants, only information considered globally will be included.

This study has been approved in August 2018 by the Ethics and Research Committee of the La Paz University Hospital in Madrid (HULP Code: PI-3320).

The sample sizes were calculated in order to find the significance of the Pearson linear correlation coefficient between two variables, for a unilateral hypothesis test according to the formula: n = [Z1-α + Z1- β / ½ ln (1 + r / 1-r)]^2 + 3 and the largest has been chosen, which involve studying 22 participants.

Taking into account the data of a previous study with participants of similar characteristics, a correlation of the parameters that set up the primary outcome, peak VO2 of r = 0.7 is assumed.

An expected drop out in rate of 0.474 has been estimated from the data obtained in another related study.

Accepting an alpha risk of 0.05 and a beta risk of 0.20 in a unilateral contrast, 22 participants are required to detect a positive correlation between the variables of the exercise tests, equal to or greater than those found in the study used as reference.

This size will guarantee sufficient power to detect correlation in the purpose of the study. To guarantee this power, and since there is not enough information about the previous values, an intermediate analysis of the data, will be carried out in the middle of the study to recalculate the size of the final sample.

The incidental sampling will be carried out according to a non-probabilistic system of consecutive cases of people diagnosed with CFS/ME.

Data analysis / Statistical methods:

  1. Descriptive: Descriptive analysis of all variables collected will be carried out. For quantitative data, centralization and dispersion measures will be calculated according to the distribution of each variable, such as mean, standard deviation, minimum and maximum median. The qualitative data will be described by absolute frequency and percentage. It will be checked if the variables are distributed normally by means of the Kolmogórov-Smirnov test for a single sample.
  2. Correlation: A bivariate analysis will be performed to observe the association between the variables obtained in the 6MWT with gases measurement and those of the peak incremental CPET; between peak VO2 in the peak CPET and the distance achieved during the 6MWT; between peak VO2 and physical activity level at baseline and after each test; and between distance achieved in the 6MWT and physical activity level at baseline and after each test. In case of normality, the Pearson product-moment correlation coefficient will be used, and if any variable is not distributed normally, the Spearman correlation analysis will be used.
  3. Linear regression: If some variables of the 6MWT are strongly correlated with the corresponding variables of the peak incremental CPET, a linear regression analysis will be performed to construct a regression equation for the prediction of the peak test performance. If necessary, a multiple linear regression analysis will be carried out to control the possible confounding variables: medication intake, time of disease evolution, quality of life, multidimensional fatigue, physical activity level at baseline, age, sex, profession, weight, height and body mass index.
  4. Comparison: a comparative analysis of physical activity level at baseline and physical activity levels after each of the tests and between physical activity levels after each of the tests to compare decrease in physical activity level that generate both tests; using repeated measures ANOVA for related samples, if they meet the normal distribution or, if not, the Friedman test.

In case of drop out, the data collected will be taken into account for the analysis.

The analysis will assume a confidence level (1 - α) of 0.95 (significance level α = 0.05). The program SPSS® Statistics version 20.0 (SPSS Incorporation, Chicago, USA) will be used.

Keywords
Work Capacity Evaluation, Fatigue Syndrome,Chronic, Exercise Tests
Medical subject headings
Fatigue Syndrome, Chronic

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Mean Value of the Peak VO2 in both Exercise Tests (6MWT and Peak CPET) in Milillitres/ Minute.

    The portable spirometer Oxycon Mobile CPET from JaegerTM during 6MWT or the fixed spirometer Mijnhart Oxycon during peak CPET will be used for its measuring. Those instruments are validated. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

Secondary outcomes (33)

  1. Mean Age of Participants in Years.

    It will be measured with the date of birth, collected by data collection sheet. Mean and standard deviation will be calculated.

    Measured: 5 minutes.

  2. Percentage of Males and Females.

    It will be collected by data collection sheet. The percentage by gender will be calculated.

    Measured: 5 minutes.

  3. Percentage of Participants´ Professions.

    Profession is an open field, works, with or without salary. It will be collected by data collection sheet. The percentage by profession will be calculated.

    Measured: 5 minutes.

  4. Mean of Time of Evolution of the Disease in Years.

    It will be measured from the date of medical diagnosis. It will be collected by data collection sheet. Mean and standard deviation will be calculated.

    Measured: 5 minutes.

  5. Percentage of Participants with Autonomic Dysfunction.

    Options yes or not, presence of orthostatic postural tachycardias and/or alterations in the Heart Rate Variability. It will be collected by data collection sheet. Percentage of participants with or without autonomic dysfunction will be calculated.

    Measured: 5 minutes.

  6. Percentage of Medications Intake.

    The type of medications consumed is an open field. It will be collected by data collection sheet. Percentage by name of medication will be calculated.

    Measured: 10 minutes.

  7. Mean of Weight in Kilograms.

    It will be measured with the Pesperson precision scale. Range 200 grams-160 kilograms. Sensitivity 100 grams. Mean and standard deviation will be calculated.

    Measured: 5 minutes.

  8. Mean of Height in Meters.

    It will be measured with the Pesperson tape height meter, range 82-200cm. Sensitivity 1mm. Mean and standard deviation will be calculated.

    Measured: 5 minutes.

  9. Mean of Body Mass Index in Kilograms/ Meters^2.

    It is calculated by dividing the weight by the square of the height with the data obtained by the two previous outcomes. Mean and standard deviation will be calculated.

    Measured: 5 minutes.

  10. Mean of Physical Activity Level at Baseline on ActivPAL 4 Micro.

    The time that participant spends lying, sitting, standing or walking is measured 7 days, 24 hours/day before both exercise tests. It will be registered with the activity meter ActivPAL4 micro, which is validated as an instrument for detecting the activity and as a tool for estimating energy expenditure, and whose data are reproducible. Mean and standard deviation will be calculated.

    Measured: 7 days.

  11. Mean Forced Vital Capacity (FVC) on Forced Spirometry in Milillitres.

    It will be performed according to the American Thoracic Society protocol with three forced spirometries The portable spirometer Oxycon Mobile CPET from JaegerTM will be used for its measuring. Mean and standard deviation will be calculated.

    Measured: 15 minutes.

  12. Mean Forced Expiratory Volume in the First Second (FEV1) on Forced Spirometry in Milillitres.

    It will be performed according to the American Thoracic Society protocol with three forced spirometries. The portable spirometer Oxycon Mobile CPET from JaegerTM will be used for its measuring. Mean and standard deviation of FEV1 will be calculated.

    Measured: 15 minutes.

  13. Mean Tiffeneau Index (FEV1 / FVC) on Forced Spirometry in Percentage.

    It is calculated with the data provided by the two previous outcomes. Mean and standard deviation will be calculated.

    Measured: 15 minutes.

  14. Mean Change from Baseline in Medications Dosage at After Both Exercise Tests (6MWT and Peak CPET).

    Open field, daily medications dosage consumed before and after both tests. It will be collected by data collection sheet. Mean and standard deviation of the differences in the dose intake by type of medication will be calculated.

    Measured: 10 minutes on day and 10 minutes another day.

  15. Mean Change from Baseline in Quality of Life Related to Health on SF-36v2 at After Both Exercise Tests.

    It is measured from 0 to 100 points by the SF-36v2 (internal consistency value α of Cronbach of 0.94). This instrument provides a profile of health status, it is usually used in studies of research in the international field in the SFC/EM and a validated version is available in Spanish. Mean and standard deviation of the differences in the total questionnaire score and in the subscales of the questionnaire will be calculated.

    Measured: 20 minutes one day and 20 minutes another day.

  16. Mean Change from Baseline in Multidimensional Fatigue on MIF:S at After Both Exercise Tests.

    It is measured from 4 to 20 points with the Multidimensional Inventory of Fatigue in Spanish (MIF: S) (internal consistency value α of Cronbach of 0.91). Mean and standard deviation of the differences will be calculated.

    Measured: 10 minutes one day and 10 minutes another day.

  17. Mean Change from Baseline in Physical Activity Level on ActivPAL 4 Micro at After each of the Exercise Tests.

    The mean change in values of the time that participant spends lying, sitting, standing or walking is measured 7 days, 24 hours/day before both exercise tests and 7 days, 24 hours/day after the 6MWT and after the peak CPET. It will be registered with the activity meter ActivPAL4 micro, which is validated as an instrument for detecting the activity and as a tool for estimating energy expenditure, and whose data are reproducible.

    Measured: 21 days, in 3 periods of 7 days.

  18. Mean Value of the Peak VO2 Body Weight Adjusted in 6MWT and in Peak CPET in Milillitres/ Kilograms/ Minute.

    The portable spirometer Oxycon Mobile CPET from JaegerTM during 6MWT or the fixed spirometer Mijnhart Oxycon during peak CPET will be used for its measuring. Those instruments are validated. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  19. Percentage of Exercise Tolerance.

    Class 1, 2, 3 or 4, classification of the impairment in exercise tolerance of the American Medical Association that is based on the values of percentage of peak VO2 body weight adjusted achieved during the exercise tests in accordance with the values of overall population. Percentage of participants in each class will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  20. Mean Distance on the 6MWT in Metres.

    It will be obtained by the 6MWT with the American Thoracic Society protocol. Mean and standard deviation will be calculated.

    Measured: 3 hours.

  21. Mean Peak Work Load on the Peak CPET in Watts.

    It is measured through the Jaeger 900 cycle ergometer during the peak CPET with Snell CR. et al protocol. Mean and standard deviation of participants´ peak work load will be calculated.

    Measured: 2 hours.

  22. Mean Change from Baseline in O2 Saturation on Spirometer at After each of the Exercise Tests.

    It is measured in percentage with a portable spirometer Oxycon Mobile CPET of JaegerTM in the 6MWT or with a fixed spirometer Mijnhart Oxycon in the peak CPET. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  23. Mean Change from Baseline in Heart Rate on Pulsiometer or Electrocardiogram at Maximum Hearth Rate in both Exercise Tests.

    It is measured in beats per minute with the heart rate sensor of the Polar TM31 band in 6MWT or with the 12-lead JaegerTM ECG in the peak CPET. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  24. Mean Change from Baseline in Heart Rate on Pulsiometer or Elecrocardiogram at After each of the Exercise Tests.

    It is measured in beats per minute with the heart rate sensor of the Polar TM31 band in the 6MWT or with the 12-lead JaegerTM ECG in the peak CPET. Mean and standard deviation of the differences in hearth rate between baseline and after the 6MWT or peak CPET will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  25. Mean Change from Baseline in Blood Pressure on Tensiometer at After each of the Exercise Tests.

    It is measured in mmHg with Suntech Oscar 2 tensionmeter in the 6MWT or Riester tensionmeter in the peak CPET. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  26. Mean Change from Baseline in Total Heart Rate Variability on Pulsiometer or Electrocardiogram at After each of the Exercise Tests.

    It will be measured in milliseconds, standard deviation of all the variations in the time interval between heartbeats measured with the heart rate sensor of the TM31 Polar band in the 6MWT or with the 12-lead JaegerTM ECG in the peak CPET. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  27. Mean of the Maximum Heart Rate in Percentage.

    It will be calculated with the value of the maximum heart rate reached and the maximum theoretical heart rate (220-patient's age) in the 6MWT and in the peak CPET. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  28. Mean Change from Baseline in VO2 on Spirometer at the Peak VO2 of the 6MWT and the Peak CPET.

    It is measured in millilitres/ minute with a portable spirometer Oxycon Mobile CPET of JaegerTM in the 6MWT or with a fixed spirometer Mijnhart Oxycon in the peak CPET. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  29. Mean Change from Baseline in VO2 Body Weight Adjusted on Spirometer at the Peak VO2 of both Exercise Tests.

    It is measured in millilitres/ minute /kilograms with a portable spirometer Oxycon Mobile CPET of JaegerTM in the 6MWT or with a fixed spirometer Mijnhart Oxycon in the peak CPET. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  30. Mean Change from Baseline in Oxygen Pulse on Spirometer at the Peak VO2 of both Exercise Tests.

    It will be measured in millilitre/ cycle with a portable spirometer Oxycon Mobile CPET of JaegerTM in the 6MWT or with a fixed spirometer Mijnhart Oxycon in the peak CPET. Mean and standard deviation in differences in oxygen pulse at baseline and at peak VO2 in both exercise tests will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  31. Mean Change from Baseline in CO2 Production on Spirometer at the Peak VO2 of both Exercise Tests.

    It will be measured in millilitre/ min with a portable spirometer Oxycon Mobile CPET of JaegerTM in the 6MWT or with a fixed spirometer Mijnhart Oxycon in the peak CPET. Mean and standard deviation in differences in CO2 production between baseline and peak VO2 in both exercise tests will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  32. Mean Change from Baseline in Respiratory Exchange Ratio (RER) at the Peak VO2 of both Exercise Tests.

    It will be measured in millilitres/ minute, is calculated with the values of O2 consumption and CO2 production before tests and at peak VO2 of both exercise tests. Mean and standard deviation will be calculated.

    Measured: 3 hours one day and 2 hours another day.

  33. Mean Change from Baseline in Minute Ventilation at the Peak VO2 of both Exercise Tests.

    It will be measured in litres/ minute with a portable spirometer Oxycon Mobile CPET of JaegerTM in the 6MWT or with a fixed spirometer Mijnhart Oxycon in the peak CPET. Mean and standard deviation of differences between baseline and at peak VO2 of both exercise tests will be calculated.

    Measured: 3 hours one day and 2 hours another day.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted18 Sep 2018
  2. Study start27 Feb 2019
  3. Primary completionJul 2025 (estimated)
  4. Study completionDec 2025 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Case only
Time perspective
Cross-sectional
Enrolment
22 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT03675087
Sponsor's protocol ID
1
Status last verified
Mar 2025
First submitted
2 Sep 2018
Last updated
10 Mar 2025
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Bennett RM. Fibromyalgia and chronic fatigue syndrome. In: Goldman L, Ausiello DA, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007. Chapter 295.

  • Fukuda K, Straus SE, Hickie I, Sharpe MC, Dobbins JG, Komaroff A. The chronic fatigue syndrome: a comprehensive approach to its definition and study. International Chronic Fatigue Syndrome Study Group. Ann Intern Med. 1994 Dec 15;121(12):953-9. doi: 10.7326/0003-4819-121-12-199412150-00009.

    PubMed 7978722

  • World Health Organization. International statistical classification of diseases and related health problems. 10th revision. Fifth edition. 2016. [internet]. Ginebra: World Health Organization; 2016. In: http://apps.who.int/classifications/icd10/browse/2016/en.

  • Engleberg N. Síndrome de fatiga crónica. En: Mandell GL, Bennett JE, Dolin R, editores, Douglas RG, colaborador. Mandell, Douglas, y Bennett. Enfermedades Infecciosas: principios y práctica. 5ª ed. Buenos Aires: Ed. Panamericana, 2002. p.1871-1877.

  • Richardson RD, Engel CC Jr. Evaluation and management of medically unexplained physical symptoms. Neurologist. 2004 Jan;10(1):18-30. doi: 10.1097/01.nrl.0000106921.76055.24.

    PubMed 14720312

  • Johnston S, Brenu EW, Staines D, Marshall-Gradisnik S. The prevalence of chronic fatigue syndrome/ myalgic encephalomyelitis: a meta-analysis. Clin Epidemiol. 2013;5:105-10. doi: 10.2147/CLEP.S39876. Epub 2013 Mar 26.

    PubMed 23576883

  • Fernandez AA, Martin AP, Martinez MI. [Chronic fatigue syndrome. Consensus document]. Aten Primaria. 2009 Oct;41(10):529-31. doi: 10.1016/j.aprim.2009.06.013. Epub 2009 Sep 9. No abstract available. Spanish.

    PubMed 19740570

  • Baker R, Shaw EJ. Diagnosis and management of chronic fatigue syndrome or myalgic encephalomyelitis (or encephalopathy): summary of NICE guidance. BMJ. 2007 Sep 1;335(7617):446-8. doi: 10.1136/bmj.39302.509005.AE. No abstract available.

    PubMed 17762037

  • Collin SM, Crawley E, May MT, Sterne JA, Hollingworth W; UK CFS/ME National Outcomes Database. The impact of CFS/ME on employment and productivity in the UK: a cross-sectional study based on the CFS/ME national outcomes database. BMC Health Serv Res. 2011 Sep 15;11:217. doi: 10.1186/1472-6963-11-217.

    PubMed 21923897

  • Russell AS, Gulliver WP, Irvine EJ, Albani S, Dutz JP. Quality of life in patients with immune-mediated inflammatory diseases. J Rheumatol Suppl. 2011 Nov;88:7-19. doi: 10.3899/jrheum.110899.

    PubMed 22045973

  • Jason LA, Benton MC, Valentine L, Johnson A, Torres-Harding S. The economic impact of ME/CFS: individual and societal costs. Dyn Med. 2008 Apr 8;7:6. doi: 10.1186/1476-5918-7-6.

    PubMed 18397528

  • Beard DD. Chronic fatigue syndrome clinical practice guidelines: psychological factors. Med J Aust. 2002 Nov 4;177(9):526; author reply 526-7. doi: 10.5694/j.1326-5377.2002.tb04937.x. No abstract available.

    PubMed 12465628

  • Turnbull N, Shaw EJ, Baker R, Dunsdon S, Costin N, Britton G, et al. National Institute for Health and Clinical Excellence. Chronic fatigue syndrome/myalgic encephalomyelitis (or encephalopathy): diagnosis and management of CFS/ME in adults and children. London: Royal College of General Practitioners; 2007. In: http://guidance.nice.org.uk/CG053

  • Nijs J, Meeus M, Van Oosterwijck J, Ickmans K, Moorkens G, Hans G, De Clerck LS. In the mind or in the brain? Scientific evidence for central sensitisation in chronic fatigue syndrome. Eur J Clin Invest. 2012 Feb;42(2):203-12. doi: 10.1111/j.1365-2362.2011.02575.x. Epub 2011 Jul 27.

    PubMed 21793823

  • Twisk FN. The status of and future research into Myalgic Encephalomyelitis and Chronic Fatigue Syndrome: the need of accurate diagnosis, objective assessment, and acknowledging biological and clinical subgroups. Front Physiol. 2014 Mar 27;5:109. doi: 10.3389/fphys.2014.00109. eCollection 2014.

    PubMed 24734022

Questions about this trial

What is this clinical trial studying?

An observational study of Fatigue Syndrome, Chronic, run by Escuela Universitaria de Fisioterapia de la Once at 1 site in Spain.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 32 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 10 Mar 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Spain. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Susana García-Juez, Lecturer (915894500 ext. 4496, sgj@once.es), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Mean Value of the Peak VO2 in both Exercise Tests (6MWT and Peak CPET) in Milillitres/ Minute. (time frame: 3 hours one day and 2 hours another day.). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03675087, which also lists 68 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Mar 2025.

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