Clinical trial NCT03926585: Variations in the DIO2 and MCT10 Genes and Effect of Triiodothyronine Treatment
Official title: Longtime Effect of Combination Treatment With L-thyroxine (L-T4) and Liothyronine (L-T3) in Patients With Persistent Hypothyroid Symptoms - Relation to Polymorphisms (SNP) in the DIO2 and the MCT10 Gene
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Hypothyroidism
Lead sponsor: Herlev Hospital
Sponsor class: OTHER
First posted: 2019-04-24
Enrollment: 82
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients in this study have been diagnosed with hypothyroidism and have had persistent hypothyroid symptoms despite L-thyroxine mono-therapy. They have all been referred to the department of endocrinology and have been examined by a trained endocrinologist. All patients have at least one year before the study initiated combination therapy with L-thyroxine and Liothyronine.

Brief summary: Hypothesis: Variations in the deiodinase 2 gene and monocarboxylate transporter 10 gene is associated with improvement in quality of life after initiation of combination therapy with L-Thyroxine and Liothyronine in patients with persistent hypothyroid symptoms despite conventional L-thyroxine mono-therapy.

Purpose: To re-test this hypothesis in patients with continued perceived effect of Liothyronine treatment at least one year after initiation in a patient population more representing of daily clinical practice. The study will help determine whether testing of specific gene variations might predict longtime effect of combination therapy.


Eligibility criteria: Inclusion Criteria:

* Patients admitted to the department of endocrinology with the diagnose hypothyroidism because of persistent hypothyroid symptoms despite treatment with L-thyroxine mono-therapy and normal and stable TSH (for at least 6 months).
* Started in combination therapy with L-thyroxine and Liothyronine in an approximately 17/1 ratio
* Exclusion of an alternative explanation for persistent hypothyroid symptoms

Exclusion Criteria:

* Initiation of L-thyroxine treatment in patients with s-TSH below upper normal limit (with assay in current use, that is TSH \< 4 mU/L)
* Ongoing pregnancy
* Age below 18 years or above 80 years.
* Patients who do not read and understand information material given
* Patients who are not competent to give informed consent

Primary outcomes:
measure: Polymorphisms in DIO2/MCT10 and triiodothyronine treatment
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
Secondary outcomes:
measure: Proportion treated with triiodothyronine
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
measure: Quality of life questionnaire
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
measure: Who controls the treatment?
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
measure: How is current treatment controlled?
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
measure: Have therapy changed after the patient left the department of endocrinology?
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
measure: TSH
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
measure: Osteoporosis
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
measure: Risk of arrhythmia
timeFrame: Single assessment point, from 1-10 years after initiation of combination therapy
Other outcomes:
Locations:
city: Herlev
country: Denmark
facility: Herlev Hospital
Study officials:
affiliation: Herlev Hospital
name: Birte Nygaard, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References: