Dosing of LT4 in Older Individuals

Hypothyroidism Clinical Trial

— DOT4  

Official title:

Levothyroxine Dosing in Older Individuals

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT06073665
• Other study ID #: 1R01AG081698-01
• Secondary ID: R01AG081698
• Status: Recruiting
• Phase: Phase 4
• Start date: January 31, 2024
• Est. completion date: April 1, 2028

Study information

• Verified date: February 2024
• Source: University of Pennsylvania
• Contact: Anne R. Cappola, M.D., Sc.M.
• Phone: 215-573-5359
• Email: acappola[@]pennmedicine.upenn.edu
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Our overall goal is to determine the clinical consequences of allowing greater flexibility in LT4 dosing in older individuals who take LT4.

Description:

Investigators will perform a randomized, parallel, double-blind clinical trial of two 6-month dosing strategies of levothyroxine (LT4) in patients aged 65 years and older who are already taking a stable dose of at least 1.2 mcg/kg/day of LT4 therapy, one to maintain a target thyroid stimulating hormone (TSH) level of 0.5-2.0 mU/L (lower TSH group) and another of a lower levothyroxine dose to achieve a target TSH of 5.5-7.0 mU/L (higher TSH group). Investigators will assess the effects of levothyroxine therapy at two different TSH targets on symptoms of hypothyroidism, mood, sleep, measures of memory and executive function, weight, lipids, and a marker of bone turnover.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 228
• Est. completion date: April 1, 2028
• Est. primary completion date: April 1, 2028
• Accepts healthy volunteers: No
• Gender: All
• Age group: 65 Years and older

Eligibility

Inclusion Criteria:

1. Provision of signed and dated informed consent form

2. Stated willingness to comply with all study procedures and availability for the duration of the study

3. Male or female, community dwelling, aged 65 years or older

4. Diagnosed with hypothyroidism of any etiology for at least 6 months, taking 75-200 mcg per day LT4 and a minimum of 1.2 mcg/kg/day with no dose adjustment since the last TSH test.

5. Ability to take oral medication and be willing to adhere to the medication regimen

Exclusion Criteria:

1. Hypopituitarism

2. History of thyroid cancer requiring suppression of TSH secretion

3. Current use of liothyronine (LT3), thyroid extracts, Tirosint liquid or capsules, and medications that interfere with thyroid function or thyroid function tests

4. GFR <30 ml/min/1.73 m2 within the prior 12 months

5. Unable to understand and comply with study requirements, as assessed by study staff and the PI, will be excluded.

6. Other conditions which, in the opinion of the investigators, would prevent them from participating in the full duration of the study.

Related Conditions & MeSH terms

• Hypothyroidism

Intervention

Drug:
• Levothyroxine Sodium
Levothyroxine dose will depend on dose at baseline and randomization group

Locations

Country	Name	City	State
United States	Penn Medicine, Smilow Translational Research Center	Philadelphia	Pennsylvania

Sponsors (2)

Lead Sponsor	Collaborator
University of Pennsylvania	National Institute on Aging (NIA)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Thyroid-Related Quality of Life Patient-Reported Outcome Quality of Life scale	22 items, scored 0-100, higher scores indicate worse status	6 months
Secondary	Thyroid-Related Quality of Life Patient-Reported Outcome Hypothyroidism subscale b. ThyPRO "Tiredness" subscale c. Thyroid Symptoms Questionnaire (TSQ)	4 items, scored 0-100, higher scores indicate worse status	6 months
Secondary	NIH Toolbox Fluid Cognition Composite Score	Adjusted scale score, based around median of 100, higher scores indicated higher function	6 months
Secondary	Geriatric Depression Scale	30 items, higher scores indicate more depressive symptoms	6 months
Secondary	Pittsburgh Sleep Quality Index	19 items, range of 0-21, higher scores indicate worse sleep	6 months
Secondary	Weight	kilograms	6 months
Secondary	LDL cholesterol	blood test, g/dL	6 months
Secondary	Satisfaction with randomized status	Participants will be asked if they can guess their randomization status and satisfaction with randomization status	6 months
Secondary	Beck Anxiety Inventory	Beck Anxiety Inventory, 21 items, range 0-63, higher scores indicate more anxiety	6 months
Secondary	Serum c-telopeptide (CTX)	Blood test, pg/mL	6 months