Subclinical hypothyroidism is common in older people and its role in health and disease in people older than 80 years is inconclusive. Some studies suggest that it is harmful, while other studies suggest benefits, making it unclear whether treatment with levothyroxine would be clinically effective. In this publication we present the protocol of the IEMO 80+ Thyroid Study in order to provide the necessary evidence base. The IEMO 80+ Thyroid Study was conducted double blind in different research centers, with people aged 80 years and older with persistent subclinical hypothyroidism being treated with either levothyroxine or placebo on a daily basis. During the follow-up period of one to three years, the effect of levothyroxine on hypothyroid complaints and fatigue was examined.
We are currently analysing the IEMO 80+ Thyroid Study data, combined with data from participants of 80 years and older from the TRUST study (Thyroid hormone Replacement for Untreated older adults with Subclinical hypothyroidism randomized placebo controlled Trial). The combined analysis of participants from both studies will provide the largest experimental evidence for the clinical effects of treatment with levothyroxine in individuals aged 80 years and older to date.Study protocol: a randomised controlled trial on the clinical effects of levothyroxine treatment for subclinical hypothyroidism in people aged 80 years and over (, 2018)