Clinical trial NCT05276856: Recovery Rate in Secondary Hypothyroidism
Official title: Rate of Recovery of Secondary Hypothyroidism in Patients With Pituitary Disorders.
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Secondary Hypothyroidism
Lead sponsor: Nova Scotia Health Authority
Sponsor class: OTHER
First posted: 2022-03-11
Enrollment: 90
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: All patients with pituitary disorders in the province of Nova Scotia are routinely enrolled in a computerized registry called the Halifax Neuropituitary (HNP) database. The database currently contains information on approximately 1800 patients. All pituitary hormonal dysfunctions are routinely identified in the HNP database. For this study, we will identify all patients with confirmed diagnosis of SHT who are currently taking T4 replacement therapy.

Brief summary: The aim of this project is to assess the rate of recovery of secondary hypothyroidism in patients with pituitary disorders.

Detailed description: The study will be conducted in three stages.

Stage 1 ( Patient identification and enrollment)

We will generate a list of all SHT patients from the HNP database and all patients will be contacted by the principal investigator (or their designate) regarding the study. Those patients who agree to participate in the study will be given a written consent form. We aim to enrol approximately 90 -100 patients for the study. Laboratory samples for serum TSH and T4 levels will be collected to confirm that all patients are adequately replaced for SHT. Those patients who are not adequately replaced and have low T4 will be excluded from the study.

Stage 2 (T4 withdrawal protocol)

Stepwise T4 replacement therapy will be initiated as follows.

Step 1:

* Reduce the dose of T4 therapy by 50% and recheck serum T4 after 2 weeks.
* If serum T4 is normal, go to step 2.
* If serum T4 drops to below normal then resume full T4 replacement (these patients will be considered as having withdrawal failure).

The rationale for testing serum T4 after 2 weeks is that the half life of T4 is up to 7 days and early testing will potentially give false results. Furthermore, serum T3 is not a reliable test in patients taking T4 therapy and will not be requested 6.

Step 2:

* Discontinue T4 therapy altogether and recheck serum TSH and T4 after 2 weeks.
* If serum T4 is normal, go to step 3.
* If serum T4 drops to below normal then resume full T4 replacement (these patients will be considered as having withdrawal failure).

Step 3:

* Recheck serum TSH and T4 after 8 weeks.
* If serum TSH and T4 levels are normal, these patients will be regarded as having successful T4 withdrawal.
* If T4 drops to below normal then resume full T4 replacement (these patients will be considered as having withdrawal failure).

Stage 3 (Analysis)

Eligibility criteria: Inclusion Criteria:

* Confirmed diagnosis of secondary hypothyroidism who are currently taking T4 replacement therapy

Exclusion Criteria:

* uncontrolled cardiovascular disease
* uncontrolled congestive heart failure
* uncontrolled mental health disorder
* not adequately replaced and have low T4 level.

Primary outcomes:
measure: Percentage of patients achieving euthyroid status
timeFrame: 12 weeks
Secondary outcomes:
Other outcomes:
Locations:
city: Halifax
country: Canada
facility: Nova Scotia Health
Study officials:
References:
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