Abstract
BackgroundSubclinical hypothyroidism (SCH) is a common condition in elderly people, defined as elevated serum thyroid-stimulating hormone (TSH) with normal circulating free thyroxine (fT4). Evidence is lacking about the effect of thyroid hormone treatment. We describe the protocol of a large randomised controlled trial (RCT) of Levothyroxine treatment for SCH.MethodsParticipants are community-dwelling subjects aged ≥65 years with SCH, diagnosed by elevated TSH levels (≥4.6 and ≤19.9 mU/L) on a minimum of two measures ≥ three months apart, with fT4 levels within laboratory reference range. The study is a randomised double-blind placebo-controlled parallel group trial, starting with levothyroxine 50 micrograms daily (25 micrograms in subjects <50Kg body weight or known coronary heart disease) with titration of dose in the active treatment group according to TSH level, and a mock titration in the placebo group. The primary outcomes are changes in two domains (hypothyroid symptoms and fatigue / vitality) on the thyroid-related quality of life questionnaire (ThyPRO) at one year. The study has 80% power (at p = 0.025, 2-tailed) to detect a change with levothyroxine treatment of 3.0% on the hypothyroid scale and 4.1% on the fatigue / vitality scale with a total target sample size of 750 patients.Secondary outcomes include general health-related quality of life (EuroQol), fatal and non-fatal cardiovascular events, handgrip strength, executive cognitive function (Letter Digit Coding Test), basic and instrumental activities of daily living, haemoglobin, blood pressure, weight, body mass index and waist circumference. Patients are monitored for specific adverse events of interest including incident atrial fibrillation, heart failure and bone fracture.DiscussionThis large multicentre RCT of levothyroxine treatment of subclinical hypothyroidism is powered to detect clinically relevant change in symptoms / quality of life and is likely to be highly influential in guiding treatment of this common condition.Trial registrationClinicaltrials.gov NCT01660126; registered 8th June 2012.
Highlights
Subclinical hypothyroidism (SCH) is a common condition in elderly people, defined as elevated serum thyroid-stimulating hormone (TSH) with normal circulating free thyroxine
Stott et al BMC Endocrine Disorders (2017) 17:6 (Continued from previous page). This large multicentre randomised controlled trial (RCT) of levothyroxine treatment of subclinical hypothyroidism is powered to detect clinically relevant change in symptoms / quality of life and is likely to be highly influential in guiding treatment of this common condition
What is subclinical hypothyroidism? Subclinical hypothyroidism means that the thyroid gland, which is found in your neck, may not be producing the right amount of thyroid hormones that your body needs to do its job well
Summary
Subclinical hypothyroidism (SCH) is a common condition in elderly people, defined as elevated serum thyroid-stimulating hormone (TSH) with normal circulating free thyroxine (fT4). Subclinical hypothyroidism (SCH) is defined as an elevated serum thyroid-stimulating hormone (TSH) with normal serum levels of free thyroxine (fT4) and few or no hypothyroid symptoms [1]. Subjects with SCH do not have the full symptom cluster of overt hypothyroidism; they often report non-specific symptoms such as tiredness, dry skin, feeling cold, puffy eyes, constipation and cognitive problems [6]. Muscle symptoms such as cramps, weakness and myalgia are more common in SCH than in euthyroid controls [7]. Subclinical hypothyroidism is a common condition among older men and women affecting up to 1 in 6 of over-65s
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
