Pilot study to investigate if reducing serotonin levels in patients with chronic fatigue syndrome is effective.

ISRCTN ISRCTN07518149
DOI https://doi.org/10.1186/ISRCTN07518149
Secondary identifying numbers N/A
Submission date
18/11/2012
Registration date
23/04/2013
Last edited
11/06/2015
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Nervous System Diseases
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
Chronic fatigue syndrome (CFS) is still an enigmatic disorder. It is complex and has a huge impact on the lives of those affected. Full recovery without treatment is rare. We still do not have a somatic explanation for the fatigue is lacking. Enhanced serotonin metabolism could play an important role in CFS. This study investigates the effect of reducing serotonin levels in patients with CFS.

Who can participate?
Female CFS-patients between 18 and 40 years, fulfilling the US Center for Disease Control and Prevention criteria can participate. Exclusion criteria are: pregnancy, previous or current participation in CFS-research, use psychotropic medication (antidepressants, sleep medication) in the last month. Vegetarians and lactating women are excluded as well.

What does the study involve?
The effect on fatigue severity, concentration and mood will be assessed. Serotonin levels can temporarily be reduced by taking an amino-acid drink without tryptophan. Tryptophan is a precursor of serotonin. There are two test-days, one week apart. On each test day patients will receive an amino acid drink. Patients will receive a dummy amino-acid drink and on the other test day patients will receive the real amino acid drink that will reduce serotonin levels. At the end of the study we will compare the effects of the real and the dummy drinks.

What are the possible benefits and risks of participating?
The effect of lowering serotonin levels in CFS patients is under investigation. It is not clear whether there will be a positive effect. During the study blood sampling will take place. Bruising can occur. The amino acid mixtures have an unpleasant taste. Nausea can occur during and after drinking the mixtures.

Where is the study run from?
The study was set up by the Radboud University Nijmegen Medical Centre, Department of General Internal Medicine, Nijmegen Expert Centre Chronic Fatigue and Donders Institute for Brain, Cognition and Behaviour (Netherlands).

When is the study starting and how long is it expected to run for?
The study ran between June and December 2011.

Who is funding the study?
Funding was provided by Prof. dr. J.K. Buitelaar
Radboud University Nijmegen Medical Center Donders Institute for Brain, Cognition and Behavior
Dept of Cognitive Neuroscience
P.O. Box 9101 (204)
6500 HB Nijmegen

Who is the main contact?
Gerard The
gkh.the@gmail.com

Contact information

Mr Gerard The
Scientific

Glenn Millerlaan 10
Goes
4462LN
Netherlands

Phone +31 11 842 52 45
Email gkh.the@gmail.com

Study information

Study designPlacebo-controlled cross-over study
Primary study designInterventional
Secondary study designRandomised cross over trial
Study setting(s)Hospital
Study typeTreatment
Participant information sheet Not available in web format, please use the contact details below to request a patient information sheet
Scientific titleThe effect of acute tryptophan depletion in chronic fatigue syndrome, a pilot study.
Study objectivesThere is clinical and experimental evidence implicating enhanced serotonin metabolism in chronic fatigue syndrome. It is hypothesed that reducing central serotonin levels is effective in chronic fatigue syndrome.
Ethics approval(s)Radboud University Nijmegen Medical Centre, 01/09/2005, ref: 2005/167
Health condition(s) or problem(s) studiedPathophysiology of chronic fatigue syndrome
InterventionAcute Tryptophan Depletion (ATD) is a reliable and reversible challenge test for serotonin.
It has widely used to investigate the role of serotonin in a variety of psychiatric disorders.
ATD is a method that significantly reduces central serotonin in human subjects. ATD is a technique that uses a combination of low tryptophan diet and a tryptophan-deficient protein load containing large amounts of other large neutral amino acids to produce maximal brain tryptophan and serotonin depletion. Within a few hours serotonin depletion can be achieved.
The effect of ATD on CFS-related symptoms, like fatigue, concentration and mood will be assessed.
Tryptophan and other amino acids levels will be assessed.
There are two test-days. On each test day baseline assessments (self-report questionnaires and blood sampling) will take place in the morning. Five hours after ingestion of the ATD mixture or the dummy mixture the assessments will be repeated. Each test day starts at 8.00 hrs and ends at 16:00 hrs.
Intervention typeOther
Primary outcome measure1. Fatigue severity
2. Concentration
3. Mood
Secondary outcome measuresNo secondary outcome measures
Overall study start date01/06/2011
Completion date31/12/2011

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
SexFemale
Target number of participants5
Key inclusion criteria1. Female CFS-patients, according to CDC criteria
2. Aged 18 - 40 years
3. Written informed consent
Key exclusion criteria1. Nursing or pregnant women
2. Current psychiatric comorbidity
3. Vegetarians
4. Use of psychotropic drugs: current or previous month
5. Current or previous engagement in CFS research
Date of first enrolment01/06/2011
Date of final enrolment31/12/2011

Locations

Countries of recruitment

  • Netherlands

Study participating centre

Glenn Millerlaan 10
Goes
4462LN
Netherlands

Sponsor information

Radboud University Nijmegen Medical Center (Netherlands)
University/education

P.O. Box 9101 (547)
Nijmegen
6500 HB
Netherlands

Phone +31 24 361 11 11
Email gkh.the@gmail.com
Website http://www.umcn.nl
ROR logo "ROR" https://ror.org/05wg1m734

Funders

Funder type

University/education

Radboud University Nijmegen Medical Center (Netherlands)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 16/09/2014 Yes No