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Myalgic Encephalomyelitis Chronic Fatigue at the National Institutes of Health

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02669212
Enrollment
52
Registered
2016-02-01
Start date
2016-10-10
Completion date
2022-01-11
Last updated
2023-04-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Chronic Fatigue Syndrome

Keywords

Chronic Fatigue Syndrome, Lyme Disease, Healthy Volunteers, Movement Disorder

Brief summary

Background: Post-Infectious Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (PI-ME/CFS) refers to long-lasting and disabling fatigue or malaise, inability to recover after exercise, and physical and emotional discomfort that may occur after a person has an infection. Researchers want to learn more about its causes. Objective: To learn more about PI-ME/CFS. Eligibility: Adults ages 18-60 years who have finished at least 7th grade education and either: have ME/CFS that started after an infection OR had Lyme disease, were treated, and returned to normal health OR are healthy volunteers Design: Participants will initially have a 2-5 day inpatient visit at the National Institutes of Health Clinical Center in Bethesda. During the visit, participants will have: Medical history Physical exam Intravenous (IV) line. A thin plastic tube is inserted into a vein. Blood and urine collected Magnetic resonance imaging (MRI). Participants will lie in a machine that takes pictures of their brain. They may get a dye through their IV. Grip strength tested Saliva, cheek swab, and stool collected Tilt table test with measures of body functions such as sweating and breathing, blood pressure, and heart rate and blood and urine sample collection Collection of blood cells. Participants can choose to have the blood drawn through the IV or through a machine that filters blood cells and returns the liquid blood back into the participant s vein. Lumbar puncture. Fluid will be removed by placement of a needle between the back bones. Heart monitoring Sleep study for participants with PI ME/CFS Questions about the participant s life and how they are feeling Questions from a neuropsychologist Questions from an occupational therapist for participants with PI ME/CFS Questinos from a nutritionist After the initial visit participants will return home. Participants evaluated for PI-ME/CFS during the first visit will have their information reviewed by an adjudication panel of experts in the diagnosis and care of ME/CFS to determine if they are eligible to participate in the second study visit. Eligible participants will be invited back for a second study visit. If a participant was taking certain medications during the first visit, they may be asked to taper off of them prior to the second visit and report any problems. They will also receive an activity monitor, fatigue diary, and nutrition log to use for at least one week prior to their second visit. Participants who are eligible will return for a 5-10 day inpatient hospital visit at the National Institutes of Health Clinical Center. During the visit, participants will undergo measurements before and up to 96 hours after performing a stationary bike exercise test. The purpose of the exercise test is to provoke ME/CFS symptoms (post-exertional malaise). Tests will be performed before and after exercise testing. These include: Sleeping in a room that measures how the body uses energy with EEG monitoring Eating a controlled diet Performing vigorous exercise for 10-15 minutes Questions about how participants are feeling Questions about what participants usually eat Samples of saliva, blood, urine and stool Wearing an activity monitor Having an Xray that measures body composition Thinking and memory tests Heart monitoring Transcranial magnetic stimulation. A brief electrical current to the scalp creates a magnetic pulse that affects brain activity. Magnetic resonance imaging (MRI). Participants will lie in a machine that takes pictures of their brain. They will do thinking and exercise tasks during the MRI. Lumbar puncture. Fluid will be removed by placement of a needle between the back bones.

Detailed description

Objective: The primary objective is to explore the clinical and biological phenotypes of post-infectious myalgic encephalomyelitis/chronic fatigue syndrome (PI-ME/CFS). The secondary objective is to explore the pathophysiology of fatigue and post-exertional malaise (PEM). Study population: Up to 206 persons will be enrolled as part of this protocol. Up to 150 persons aged 18-60 will be part of 3 study groups: 50 ME/CFS patients whose fatigue began after an infection, 50 non-fatigued participants with a documented history of a full recovery from COVID-19 infection, and 50 healthy volunteers. The study has a target of completing all study procedures on 20 enrolled participants in each group. Up to an additional 36 persons reporting a community diagnosis of ME/CFS will be enrolled into focus groups to discuss the experience of post-exertional malaise. Up to an additional 10 healthy volunteers and 10 ME/CFS patients may be enrolled to refine the protocol's electrophysiological and neuroimaging techniques. Design: This is a single-center, exploratory, cross-sectional study of PI-ME/CFS. Participants will have a phenotyping visit, which will encompass a 2-5 day long inpatient admission at the NIH Clinical Center. Case status for ME/CFS participants will be determined after the phenotyping visit by a case adjudication process utilizing an expert physician committee and published guidelines. Adjudicated participants meeting inclusion criteria will be invited back to participate in an exercise stress visit, which will encompass a 5-10 day long inpatient admission. Detailed subjective and objective measurements and biological specimens will be serially collected before and up to 96 hours after a peak exercise test capable of inducing post-exertional malaise during this visit. All procedures will be completed on all three study groups to allow for optimal inter-group comparisons. Outcome measures: The primary purpose of this protocol is to perform exploratory analysis of collected samples for the generation of new hypotheses regarding ME/CFS. The types of analyses to be performed will be wide ranging. Planned areas of focus include: 1. Characterization of the immune system and inflammation at baseline 2. Characterization of the pattern of microbiome in collected samples at baseline 3. Characterization of bioenergetics, autonomic, and metabolic function in collected samples at baseline 4. Characterization of neurocognition at baseline 5. Characterization of autonomic function at baseline

Interventions

All participants will undergo an exercise stress test

Sponsors

National Institute of Neurological Disorders and Stroke (NINDS)
Lead SponsorNIH

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
SCREENING
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No

Inclusion criteria

* INCLUSION CRITERIA: * Inclusion criteria for all participants 1. Adult participants aged 18-60 years at the time of enrollment. 2. Self-reported completion of at least the 7th grade of school. 3. Ability to speak, read, and understand English. 4. Willing and able to complete all study procedures 5. Participant has a primary care physician at the time of enrollment. 6. Able to provide informed consent. * Additional inclusion criteria for participants with PI-ME/CFS for the phenotyping visit: 1. A self-reported illness narrative of the development of persistent fatigue and post-exertional malaise as the consequence of an acute infection. The persistent fatigue may have an acute onset or become progressively worse over 6 months. 2. Licensed Independent Practitioner documentation of ME/CFS onset: * Medical documentation of absence of symptoms within one year of ME/CFS onset. This may include medical records, letters, or information gathered from telephone calls with study personnel. * Documentation of a medical evaluation for symptoms of an acute infection or documentation of a medical evaluation of persistent symptoms within 2 months following an assumed infection. 3. Persistent fatigue and PEM onset less than 5 years prior to enrollment. * Additional inclusion criteria for participants with PI-ME/CFS for the exercise stress visit: 1. Be unanimously considered to be a case of PI-ME/CFS by the protocol s adjudication committee. 2. Meet the 1994 Fukuda Criteria or the 2003 Canadian Consensus Criteria for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome or the Institute of Medicine Diagnostic Criteria.. 3. Have moderate to severe clinical symptom severity: * Severe fatigue as determined using the Multidimensional Fatigue Inventory (MFI): score of greater than or equal to 13 on the general fatigue subscale or greater than or equal to 10 on the reduced activity subscale. * Functional impairment as determined using the Short-Form 36 (SF-36): score of less than or equal to 70 physical function subscale, or less than or equal to 50 on role physical subscale, or less than or equal to 75 on social function subscale * Additional inclusion criteria for healthy volunteer group: None * Additional inclusion criteria for COVID-19 Healthy Volunteers: documented prior COVID19 infection as evidenced by: 1. A history of clinical manifestations compatible with COVID-19 2. Laboratory evidence of Covid-19 infection: * Detectionof SARS-CoV-2RNA or antigen in nasopharyngeal swab, sputum, other sample source with Emergency Use Authorization/approval from the FDA; OR * A positive antibody test using an assay that has received Emergency Use Authorization/approval from the FDA 3. Has been recovered from the COVID-19 infection for at least six months and no more than five years.

Exclusion criteria

*

Design outcomes

Primary

MeasureTime frameDescription
Cardiopulmonary Exercise Test (CPET) - ATVO2relAt time of AT during CPETThe Relative Volume of Oxygen at the Anaerobic Threshold (ATVO2rel) was determined during a cardiopulmonary exercise test (CPET). ATVO2rel represents the volume of oxygen being consumed when a participant reaches AT, adjusted for their weight during the CPET. Results compared Healthy Volunteer Participants to ME/CFS Participants.
Cardiopulmonary Exercise Test (CPET) - RERAt time of AT during CPETThe Respiratory Exchange Ratio (VCO2/VO2) was determined during a cardiopulmonary exercise test (CPET). VCO2/VO2 is calculated by measuring the volume of carbon dioxide and oxygen the participant breathes during CPET. When the volume of carbon dioxide exceeds that of oxygen, it reflects a change from aerobic metabolism to anaerobic metabolism. When a participant has a Respiratory Exchange Ratio (RER) during CPET that is equal or greater than 1.1 it is considered a sufficient exercise effort. Results compared Healthy Volunteer Participants to ME/CFS Participants.

Other

MeasureTime frameDescription
Characterization of the Immune System and Inflammation - ESRBaselineBlood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the results of the Erythrocyte Sedimentation Rate (ESR), i.e., a measure of how quickly red blood cells settle at the bottom of a test tube, in the two populations is reported. A faster than normal rate of settling suggests inflammation.
Characterization of the Immune System and Inflammation - CRPBaselineBlood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the results of C-Reactive Protein (CRP), i.e., a measurement of a protein that is made by the liver, in the two populations is reported. A higher level than normal suggests inflammation.
Characterization of the Immune System and Inflammation - WBC in CFSBaselineBlood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the White Blood cell Count in Cerebrospinal Fluid (WBC in CFS), i.e., a measurement of the number of white blood cells in the cerebrospinal fluid, in the two populations is reported. Higher levels than normal suggest inflammation or infection in the central nervous system.
Mitochondrial Extracellular Flux AssayBaselineThe oxygen consumption rate of peripheral blood mononuclear cells per unit of time when the cells are in their normal, unprovoked state of function measured in Basal (units) was measured in Healthy and ME/CFS participants at baseline. This is a standard measure of mitochondrial respiration that is responsible for providing energy to cells.
Characterization of Total Body Energy Use (Bioenergetics/Metabolic)12 hoursThe total amount of energy expended per unit of time as measured by whole-room indirect calorimetry. This method measures the amount of oxygen consumed and carbon dioxide produced which can be used to calculate the amount of energy produced by biological oxidation and is measured by kilocalories per day. Measures were taken from Healthy and ME/CFS participants.
Clinical Response Effect of Tilt Table TestingBaselinePersons with autonomic dysfunction will often have symptoms provoked by having an up-to-40 minutes long tilt table test. The percentage of participants in each group having severe enough symptoms which required the test to be stopped in Healthy and ME/CFS participants at baseline.
Characterization of the Pattern of Microbiome in StoolBaselineStool samples were taken from Healthy and ME/CFS participants at baseline. The number of specific types of bacteria, using the Least Known Taxon (LTK) units, were measured with the Shotgun Metagenomic method.
Test of Variables of Attention (TOVA)BaselineThe TOVA is a measure of cognitive function that assesses attention and inhibitory control. The test is used to measure a number of variables involving the test taker's response to either a visual or auditory stimulus measured during a simple, yet boring, computer game. These measurements are then compared to the measurements of a group of people without attention disorders who took the T.O.V.A. The range of values for the score, after normalization to the population, is -10 to +10, with a lower score representing a worse attention score. The test was administered to Healthy and ME/CFS participants at baseline.
Paced Auditory Serial Addition Test (PASAT)BaselineThe PASAT is a measure of cognitive function that assesses auditory information processing speed and flexibility, as well as calculation ability. Single digits are presented every 3 seconds and the patient must add each new digit to the one immediately prior to it. The test score is the total number of correct trials out of a possible 60. The test was administered to Healthy and ME/CFS participants at baseline.
Effect of Maximal Exertion on Autonomic Function as Measured by SDNNi in Healthy and ME/CFS Participants.BaselineVariability of the time between heartbeats can be used to measure alterations in autonomic function. The Standard Deviation of the Normal-to-Normal Intervals (SDNNi) is a measure of the amount of beat to beat variability between each normal heartbeat collected over a 24 hour period. These results compare the SDNNi in healthy and ME/CFS participants at baseline.
Characterization of the Immune System and Inflammation - WBCBaselineBlood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the White Blood Cell (WBC) Count, i.e., a measurement of the number of white blood cells in the blood, in the two populations is reported. Low values can suggest immune deficiencies. High values can suggest infection or inflammation.

Countries

United States

Participant flow

Recruitment details

Participants were either referred to study investigators by their primary care physician or were self-referred either through the Patient Recruitment and Public Liaison (PRPL) office or direct contact. Interested participants were contacted by telephone to evaluate eligibility. Eligible participants were subsequently seen at the NIH Clinical Center for study visits. Recruitment began February 2016 and ended February 2020.

Pre-assignment details

Participants underwent telephone screening followed by a medical record review/discussion with the participant's physician to determine general eligibility. Participants were invited to campus to determine if they met inclusion/exclusion criteria for the phenotyping phase of the study. After the phenotyping visit, results were reviewed by a panel of expert adjudicators to determine case status and eligibility for the exercise phase of the protocol. No Lyme disease participants were recruited.

Participants by arm

ArmCount
Healthy Volunteer Participants
Participants found to be healthy after a medical and psychiatric evaluation.
25
ME/CFS Participants
Participants with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome
27
Total52

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyExcluded - determined NOT post-infectious04
Overall StudyLost to Follow-up10
Overall StudyMedical Condition34
Overall StudyWithdrawal by Subject02

Baseline characteristics

CharacteristicHealthy Volunteer ParticipantsME/CFS ParticipantsTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
25 Participants27 Participants52 Participants
Age, Continuous42.24 Years
STANDARD_DEVIATION 13.46
37.82 Years
STANDARD_DEVIATION 14.72
40.35 Years
STANDARD_DEVIATION 13.48
Ethnicity (NIH/OMB)
Hispanic or Latino
2 Participants2 Participants4 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
23 Participants25 Participants48 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants2 Participants2 Participants
Race (NIH/OMB)
Black or African American
1 Participants0 Participants1 Participants
Race (NIH/OMB)
More than one race
3 Participants0 Participants3 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
21 Participants25 Participants46 Participants
Sex: Female, Male
Female
13 Participants13 Participants26 Participants
Sex: Female, Male
Male
12 Participants14 Participants26 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 250 / 27
other
Total, other adverse events
14 / 2523 / 27
serious
Total, serious adverse events
0 / 250 / 27

Outcome results

Primary

Cardiopulmonary Exercise Test (CPET) - ATVO2rel

The Relative Volume of Oxygen at the Anaerobic Threshold (ATVO2rel) was determined during a cardiopulmonary exercise test (CPET). ATVO2rel represents the volume of oxygen being consumed when a participant reaches AT, adjusted for their weight during the CPET. Results compared Healthy Volunteer Participants to ME/CFS Participants.

Time frame: At time of AT during CPET

Population: COVID-19 pandemic halted return visit for participation in Exercise Phase of trial.

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCardiopulmonary Exercise Test (CPET) - ATVO2rel16.0 mL/kg/minStandard Deviation 4.3
ME/CFS ParticipantsCardiopulmonary Exercise Test (CPET) - ATVO2rel10.6 mL/kg/minStandard Deviation 3.8
Primary

Cardiopulmonary Exercise Test (CPET) - RER

The Respiratory Exchange Ratio (VCO2/VO2) was determined during a cardiopulmonary exercise test (CPET). VCO2/VO2 is calculated by measuring the volume of carbon dioxide and oxygen the participant breathes during CPET. When the volume of carbon dioxide exceeds that of oxygen, it reflects a change from aerobic metabolism to anaerobic metabolism. When a participant has a Respiratory Exchange Ratio (RER) during CPET that is equal or greater than 1.1 it is considered a sufficient exercise effort. Results compared Healthy Volunteer Participants to ME/CFS Participants.

Time frame: At time of AT during CPET

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCardiopulmonary Exercise Test (CPET) - RER1.3011 RatioStandard Deviation 0.0791
ME/CFS ParticipantsCardiopulmonary Exercise Test (CPET) - RER1.2415 RatioStandard Deviation 0.1156
Other Pre-specified

Characterization of the Immune System and Inflammation - CRP

Blood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the results of C-Reactive Protein (CRP), i.e., a measurement of a protein that is made by the liver, in the two populations is reported. A higher level than normal suggests inflammation.

Time frame: Baseline

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCharacterization of the Immune System and Inflammation - CRP3.29 mg/LStandard Deviation 6.85
ME/CFS ParticipantsCharacterization of the Immune System and Inflammation - CRP1.4 mg/LStandard Deviation 2.22
Other Pre-specified

Characterization of the Immune System and Inflammation - ESR

Blood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the results of the Erythrocyte Sedimentation Rate (ESR), i.e., a measure of how quickly red blood cells settle at the bottom of a test tube, in the two populations is reported. A faster than normal rate of settling suggests inflammation.

Time frame: Baseline

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCharacterization of the Immune System and Inflammation - ESR7.43 mm/hrStandard Deviation 6.13
ME/CFS ParticipantsCharacterization of the Immune System and Inflammation - ESR10.1 mm/hrStandard Deviation 11.9
Other Pre-specified

Characterization of the Immune System and Inflammation - WBC

Blood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the White Blood Cell (WBC) Count, i.e., a measurement of the number of white blood cells in the blood, in the two populations is reported. Low values can suggest immune deficiencies. High values can suggest infection or inflammation.

Time frame: Baseline

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCharacterization of the Immune System and Inflammation - WBC5.907 number of WBCs(K)/uLStandard Deviation 1.536
ME/CFS ParticipantsCharacterization of the Immune System and Inflammation - WBC6.143 number of WBCs(K)/uLStandard Deviation 1.243
Other Pre-specified

Characterization of the Immune System and Inflammation - WBC in CFS

Blood and CSF were collected from healthy and ME/CFS participants at baseline. A comparison of the White Blood cell Count in Cerebrospinal Fluid (WBC in CFS), i.e., a measurement of the number of white blood cells in the cerebrospinal fluid, in the two populations is reported. Higher levels than normal suggest inflammation or infection in the central nervous system.

Time frame: Baseline

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCharacterization of the Immune System and Inflammation - WBC in CFS1.0 number WBCs/uLStandard Deviation 1.124
ME/CFS ParticipantsCharacterization of the Immune System and Inflammation - WBC in CFS1.313 number WBCs/uLStandard Deviation 1.662
Other Pre-specified

Characterization of the Pattern of Microbiome in Stool

Stool samples were taken from Healthy and ME/CFS participants at baseline. The number of specific types of bacteria, using the Least Known Taxon (LTK) units, were measured with the Shotgun Metagenomic method.

Time frame: Baseline

Population: Single batch analyzed on subset of participants

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCharacterization of the Pattern of Microbiome in Stool477 LTKStandard Deviation 32.9
ME/CFS ParticipantsCharacterization of the Pattern of Microbiome in Stool427 LTKStandard Deviation 44.1
Other Pre-specified

Characterization of Total Body Energy Use (Bioenergetics/Metabolic)

The total amount of energy expended per unit of time as measured by whole-room indirect calorimetry. This method measures the amount of oxygen consumed and carbon dioxide produced which can be used to calculate the amount of energy produced by biological oxidation and is measured by kilocalories per day. Measures were taken from Healthy and ME/CFS participants.

Time frame: 12 hours

Population: Procedure added to Phenotyping Phase after enrollment started.

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersCharacterization of Total Body Energy Use (Bioenergetics/Metabolic)1858.9 kcal/dayStandard Deviation 353.3
ME/CFS ParticipantsCharacterization of Total Body Energy Use (Bioenergetics/Metabolic)1862.1 kcal/dayStandard Deviation 390.5
Other Pre-specified

Clinical Response Effect of Tilt Table Testing

Persons with autonomic dysfunction will often have symptoms provoked by having an up-to-40 minutes long tilt table test. The percentage of participants in each group having severe enough symptoms which required the test to be stopped in Healthy and ME/CFS participants at baseline.

Time frame: Baseline

Population: Two participants were unable to complete due to technical difficulties with procedure.

ArmMeasureValue (NUMBER)
Healthy VolunteersClinical Response Effect of Tilt Table Testing36.8 percentage of participants
ME/CFS ParticipantsClinical Response Effect of Tilt Table Testing58.8 percentage of participants
Other Pre-specified

Effect of Maximal Exertion on Autonomic Function as Measured by SDNNi in Healthy and ME/CFS Participants.

Variability of the time between heartbeats can be used to measure alterations in autonomic function. The Standard Deviation of the Normal-to-Normal Intervals (SDNNi) is a measure of the amount of beat to beat variability between each normal heartbeat collected over a 24 hour period. These results compare the SDNNi in healthy and ME/CFS participants at baseline.

Time frame: Baseline

Population: Data from participants on cardiac medications were excluded.

ArmMeasureValue (MEAN)
Healthy VolunteersEffect of Maximal Exertion on Autonomic Function as Measured by SDNNi in Healthy and ME/CFS Participants.67.8 ms
ME/CFS ParticipantsEffect of Maximal Exertion on Autonomic Function as Measured by SDNNi in Healthy and ME/CFS Participants.56.3 ms
Other Pre-specified

Mitochondrial Extracellular Flux Assay

The oxygen consumption rate of peripheral blood mononuclear cells per unit of time when the cells are in their normal, unprovoked state of function measured in Basal (units) was measured in Healthy and ME/CFS participants at baseline. This is a standard measure of mitochondrial respiration that is responsible for providing energy to cells.

Time frame: Baseline

Population: Technical issues with assay prevented complete dataset.

ArmMeasureValue (MEDIAN)
Healthy VolunteersMitochondrial Extracellular Flux Assay46.7 Pmol/min
ME/CFS ParticipantsMitochondrial Extracellular Flux Assay52.1 Pmol/min
Other Pre-specified

Paced Auditory Serial Addition Test (PASAT)

The PASAT is a measure of cognitive function that assesses auditory information processing speed and flexibility, as well as calculation ability. Single digits are presented every 3 seconds and the patient must add each new digit to the one immediately prior to it. The test score is the total number of correct trials out of a possible 60. The test was administered to Healthy and ME/CFS participants at baseline.

Time frame: Baseline

Population: Not all participants were able to complete test.

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersPaced Auditory Serial Addition Test (PASAT)52.4 score on a scaleStandard Deviation 12.1
ME/CFS ParticipantsPaced Auditory Serial Addition Test (PASAT)52 score on a scaleStandard Deviation 11
Other Pre-specified

Test of Variables of Attention (TOVA)

The TOVA is a measure of cognitive function that assesses attention and inhibitory control. The test is used to measure a number of variables involving the test taker's response to either a visual or auditory stimulus measured during a simple, yet boring, computer game. These measurements are then compared to the measurements of a group of people without attention disorders who took the T.O.V.A. The range of values for the score, after normalization to the population, is -10 to +10, with a lower score representing a worse attention score. The test was administered to Healthy and ME/CFS participants at baseline.

Time frame: Baseline

Population: Not all participants were able to complete test.

ArmMeasureValue (MEAN)Dispersion
Healthy VolunteersTest of Variables of Attention (TOVA)1.1 score on a scaleStandard Deviation 3.6
ME/CFS ParticipantsTest of Variables of Attention (TOVA)0.9 score on a scaleStandard Deviation 4.7

Source: ClinicalTrials.gov · Data processed: Feb 9, 2026