Contact information
Type
Scientific
Primary contact
Dr John David Spence
ORCID ID
Contact details
Stroke Prevention & Atherosclerosis Research Centre (SPARC)
Robarts Research Institute
Siebens-Drake Research Bldg.
1400 Western Rd
London
Ontario
N6G 2V2
Canada
+1 519 663 3113
dspence@robarts.ca
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
MCT-79197
Study information
Scientific title
Effect of L-thyroxine on progression of Carotid Atherosclerosis in Subclinical Hypothyroidism: a single centre, randomised, two-arm parallel, placebo-controlled drug intervention
Acronym
T4CASH
Study hypothesis
Primary hypothesis:
That treatment of patients with subclinical hypothyroidism with L-thyroxine to achieve a target thyroid stimulating hormone (TSH) less than 2 and greater than 0.4 mIU/L and free thyroxine (FT4) greater than 4 and less than 25 pmol/L, will slow progression of carotid plaque volume and carotid intima-media thickness (IMT), compared to placebo.
Secondary hypotheses:
That treatment with L-thyroxine will improve control of plasma lipids and homocysteine, and reduce levels of C-reactive protein, weight, waist circumference and insulin resistance.
Please note that as of 04/03/2009 the anticipated end date in this record was amended; the previous date at the time of registration was:
Initial anticipated end date: 31/07/2007
Ethics approval
Research Ethics Board of the University of Western Ontario gave approval on the 24th June 2004 (ref: 10458).
Study design
Single centre, randomised, double blind (participant, investigator, caregiver, outcome assessor and data analyst), two-arm parallel, placebo-controlled drug intervention
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Hospitals
Trial type
Treatment
Patient information sheet
Condition
Atherosclerosis, subclinical hypothyroidism
Intervention
1. L-thyroxine, beginning at 0.0125 and gradually increased to achieve target TSH level greater than 0.4 and less than 2 and FT4 greater than 4 and less than 25 pmol/L for 18 months
2. Matching placebo, with dummy dose adjustments for 18 months
Contact for public queries:
Tisha Mabb
Lab Manager
Stroke Prevention & Atherosclerosis Research Centre (SPARC)
Robarts Research Institute
Siebens-Drake Research Bldg.
1400 Western Rd
London, Ontario
N6G 2V2
Canada
Email: tisha@robarts.ca
Intervention type
Drug
Phase
Not Applicable
Drug names
L-thyroxine
Primary outcome measure
Rate of progression of carotid plaque volume (mm^3) measured by 3-D ultrasound at baseline and 18 months.
Secondary outcome measures
1. Intima-media thickness (IMT), measured at baseline and 18 months
2. Weight, waist circumference, measured every 6 months
3. Insulin resistance by Homeostasis Model Assessment (HOMA), homocysteine, lipids, measured at baseline and 19 months
Overall trial start date
01/07/2006
Overall trial end date
31/07/2010
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
Male or female patients:
1. With subclinical hypothyroidism, defined as a TSH of 3 to 10 mU/L, and a normal serum free thyroxine level (FT4 11 to 25 pmol/L), and
2. Measurable plaque in the carotid arteries
3. Aged greater than or equal to 45 years
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
254
Participant exclusion criteria
1. Unwilling to give informed consent
2. History of atrial fibrillation
3. Unstable angina, or angina requiring nitroglycerine as often as once a month
4. Unlikely to adhere to the protocol
5. Unlikely to survive 18 months because of severe illness such as cancer
6. At risk of pregnancy
Recruitment start date
01/07/2006
Recruitment end date
31/07/2010
Locations
Countries of recruitment
Canada
Trial participating centre
Stroke Prevention & Atherosclerosis Research Centre (SPARC)
London, Ontario
N6G 2V2
Canada
Sponsor information
Organisation
Robarts Research Institute (Canada)
Sponsor details
P.O. Box 5015
100 Perth Drive
London
Ontario
N6A 5K8
Canada
+1 519 663 5777
lchapman@robarts.ca
Sponsor type
Research organisation
Website
Funders
Funder type
Research organisation
Funder name
Canadian Institutes of Health Research (CIHR) (Canada) - http://www.cihr-irsc.gc.ca (ref: MCT-79197)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
Publication list