Condition category
Circulatory System
Date applied
21/05/2008
Date assigned
21/05/2008
Last edited
04/03/2009
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

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 measures

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

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

http://www.robarts.ca/home.php

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

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes