Thyroid Hormone Replacement for Subclinical Hypothyroidism
Status:
Completed
Trial end date:
2016-11-18
Target enrollment:
Participant gender:
Summary
Subclinical hypothyroidism (SCH) is a common condition among older men and women. Although by
definition SCH comprises biochemically mild thyroid hormone deficiency without overt
symptoms, it is a possible contributor to multiple problems in older age. Thyroid hormone has
effects on numerous physiological systems, including the vascular tree, heart, skeletal
muscle and brain. Therefore, thyroxine substitution to overcome thyroid hormone deficiency
has the potential to give multisystem benefits to older people with SCH.
Small studies have reported reduced atherosclerosis and improved heart function with
thyroxine replacement, but no large clinical trials have been performed. Therefore the
available evidence is limited, leading to major variations in guidelines and clinical
practice, with uncertainty regarding the indications for screening and treatment. The
investigators propose a multicentre randomised placebo controlled trial to assess the impact
of thyroxine replacement in a minimum of 540 older adults (maximum 750) with persisting SCH
(excluding those in whom it is a temporary phenomenon who are unlikely to benefit). The
investigators will include older men and women with a wide age range and of varying health
status. Outcomes include health related quality of life, muscle strength, executive cognitive
function and cardiovascular events, with a minimum of 1 year of follow up. Blood and urine
samples will be stored in a biobank, to allow future research on causes of ill health in
older people with SCH.
The investigators have the support of patient advocacy groups and a consortium with the wide
range of expertise and experience required to conduct large scale multicentre clinical
trials. The proposal explores the multisystem and quality of life benefits to older people of
a tailored approach to management of SCH.
This clinical trial should definitively clarify whether thyroxine treatment for SCH provides
benefits that are relevant for patients. This trial will provide strong evidence with the
potential to improve clinical practice, reduce health care costs and promote healthy ageing
of older adults.
Phase:
Phase 4
Details
Lead Sponsor:
NHS Greater Glasgow and Clyde
Collaborators:
Leiden University Medical Center University College Cork University of Bern University of Glasgow