Turner And Klinefelter Treatment Target Study (TAKTT)
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ClinicalTrials.gov Identifier: NCT04803474 |
Recruitment Status :
Recruiting
First Posted : March 17, 2021
Last Update Posted : March 30, 2021
|
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Rationale: Health related Quality of life (HRQoL) is impaired in patients with Turner and Klinefelter syndrome (TS and KS). It is unknown what the optimal endocrine treatment target values are that maximize HRQoL in patients with these syndromes. Therefore the relation between HRQoL and biochemical parameters will be studied in large cohorts of patients with TS and KS. This information will give essential insight that will help to improve endocrine treatment and HRQoL in these patients.
Research objectives: To explore the relationship between biochemical parameters and HRQoL in patients with TS and KS.
Hypothesis: Biochemical parameters are related to HRQoL in patients with TS and KS.
Study design: Cross-sectional, observational, multicentre study Study population: Patients with KS or TS, 18 years or older Methods and procedures: To measure fatigue the Checklist Individual Strength (CIS-20) will be used, for QoL the 5-level EQ-5D (EQ-5D-L5) will be used and for stress the Perceived Stress Scale (PSS) and hair cortisol levels. For patients with KS the anxiety scale from the Liebowitz social anxiety scale (LSAS) will be used to measure social anxiety. To measure the long-term exposure to testosterone in KS patients, testosterone concentrations in hair will be measured. For patients with KS, all questions from the questionnaires will be discussed orally during a visit to the outpatients clinic. One extra tube of blood and a strand of hair will be collected during routine blood withdrawal. All other variables are already part of the standard patient care and are available in patient records. For patients with TS all information including the questionnaires and laboratory values is already available and will be collected from clinical records.
Main study parameters/endpoints: The relationship between different hormonal parameters and HRQoL as measured by questionnaires. The main hormonal parameter that will be investigated in KS is testosterone in hair. For patients with Turner syndrome, free thyroxine (FT4), thyroid stimulating hormone (TSH) and liver enzymes, which have already been collected, will be investigated. The relationships between the EQ-5D-L5 score and testosterone in hair (in patients with KS) and thyroid hormone status (in patients with TS) are the primary outcomes.
Condition or disease | Intervention/treatment |
---|---|
Klinefelter Syndrome Turner Syndrome | Diagnostic Test: Measurement of blood values, questionnaire scores and measurements of hormone levels in hair |

Study Type : | Observational |
Estimated Enrollment : | 370 participants |
Observational Model: | Cohort |
Time Perspective: | Prospective |
Official Title: | Turner And Klinefelter Treatment Target Study. Improving Endocrine Treatment by Linking Biochemical Parameters to Morbidity and Quality of Life in Patients With Turner and Klinefelter Syndrome |
Actual Study Start Date : | July 1, 2018 |
Estimated Primary Completion Date : | July 1, 2021 |
Estimated Study Completion Date : | December 1, 2021 |

Group/Cohort | Intervention/treatment |
---|---|
Klinefelter
Patients with Klinefelter syndrome
|
Diagnostic Test: Measurement of blood values, questionnaire scores and measurements of hormone levels in hair
Measurement of blood values, questionnaire scores and measurements of hormone levels in hair |
Turner
Patient with Turner syndrome
|
Diagnostic Test: Measurement of blood values, questionnaire scores and measurements of hormone levels in hair
Measurement of blood values, questionnaire scores and measurements of hormone levels in hair |
- The relationship between thyroid hormone status* and QoL as measured by the EQ-5D-5L in patients with TS. [ Time Frame: At study entry (cross-sectional study). There is just one visit per patient. The total study has an approximately duration of 3-4 years. ]
thyroid hormone status is a variable that consists of the following 6 categories:
- Overt hyperthyroidism (FT4>25pmol/L and TSH<0,4mU/L)
- Overt hypothyroidism (FT4 <11 pmol/L and TSH >4,3 mU/L)
- Subclinical hypothyroidism with TSH <10mU/L (FT4 11-25 pmol/L and TSH 4,3-10mU/L)
- Subclinical hypothyroidism with TSH >10mU/L (FT4 11-25 pmol/L and TSH > 10mU/L)
- Subclinical hyperthyroidism (FT4 11-25 pmol/L and TSH <0,4 mU/L)
- Euthyroidism (FT4 11-25 pmol/L and TSH 0,4- 4,3 mU/L)
The range of the EQ-5D-5L is from 0 to 100. A higher score means a better outcome.
- The relationship between testosterone concentrations in hair and QoL as measured by the EQ-5D-5L in patients with KS. [ Time Frame: At study entry (cross-sectional study). There is just one visit per patient. The total study has an approximately duration of 3-4 years. ]The range of the EQ-5D-5L is from 0 to 100. A higher score means a better outcome.
Biospecimen Retention: Samples With DNA

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Sampling Method: | Non-Probability Sample |
Inclusion Criteria:
- Klinefelter or Turner syndrome as confirmed by genetic testing
- Sufficient knowledge of the Dutch language to complete the questionnaires
- At least 18 years old
Exclusion Criteria:
- KS: Patients not under treatment in the EMC, AMC or VUmc or no planned visits during the study period
- TS: No laboratory values or no questionnaires available in patient records
- Severe psychiatric or neurologic disorders or other reasons for inability to complete the questionnaires as assessed by the treating physician.
- Failure to obtain informed consent

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04803474
Contact: Laura de Graaff, MD, PhD | +31618843010 | l.degraaff@erasmusmc.nl |
Netherlands | |
Erasmus Medical Center | Recruiting |
Rotterdam, Zuid-Holland, Netherlands, 3015 GD | |
Contact: Laura CG de Graaff, MD, PhD +31618843010 l.degraaff@erasmusmc.nl | |
Sub-Investigator: Sabine E Hannema |
Principal Investigator: | Laura de Graaff, MD, PhD | Department of Internal Medicine - Endocrinology, Erasmus MC, Rotterdam, the Netherlands |
Responsible Party: | dr. Laura C. G. de Graaff-Herder, Principal investigator, Erasmus Medical Center |
ClinicalTrials.gov Identifier: | NCT04803474 |
Other Study ID Numbers: |
NL65814.078.18 |
First Posted: | March 17, 2021 Key Record Dates |
Last Update Posted: | March 30, 2021 |
Last Verified: | March 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Plan Description: | Data available upon reasonable request |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Turner Syndrome Gonadal Dysgenesis Klinefelter Syndrome Syndrome Disease Pathologic Processes Disorders of Sex Development Urogenital Abnormalities Sex Chromosome Disorders of Sex Development Heart Defects, Congenital Cardiovascular Abnormalities Cardiovascular Diseases |
Heart Diseases Congenital Abnormalities Sex Chromosome Disorders Chromosome Disorders Genetic Diseases, Inborn Gonadal Disorders Endocrine System Diseases Hypogonadism Hormones Hormones, Hormone Substitutes, and Hormone Antagonists Physiological Effects of Drugs |