The optimal healthy ranges of thyroid function defined by the risk of cardiovascular disease and mortality: systematic review and individual participant data meta-analysis.

Background: Reference intervals of thyroid-stimulating hormone (TSH) and free thyroxine (FT) are statistically defined by the 2·5-97·5th percentiles, without accounting for potential risk of clinical outcomes. We aimed to define the optimal healthy ranges of TSH and FT based on the risk of cardiovascular disease and mortality.

Methods: This systematic review and individual participant data (IPD) meta-analysis identified eligible prospective cohorts through the Thyroid Studies Collaboration, supplemented with a systematic search via Embase, MEDLINE (Ovid), Web of science, the Cochrane Central Register of Controlled Trials, and Google Scholar from Jan 1, 2011, to Feb 12, 2017 with an updated search to Oct 13, 2022 (cohorts found in the second search were not included in the IPD).

The Relation Between Thyroid Function and Anemia: A Pooled Analysis of Individual Participant Data.

Context: Anemia and thyroid dysfunction often co-occur, and both increase with age. Human data on relationships between thyroid disease and anemia are scarce.

Objective: To investigate the cross-sectional and longitudinal associations between clinical thyroid status and anemia.

Thyrotoxicosis associated with the use of amiodarone: the utility of ultrasound in patient management.

Amiodarone is an anti-arrhythmic drug that commonly affects the thyroid, causing hypothyroidism or thyrotoxicosis. Amiodarone-induced thyrotoxicosis (AIT) is caused by excessive thyroid hormone biosynthesis in response to iodine load in autonomously functioning thyroid glands with pre-existing nodular goitre or underlying Graves' disease (type 1 or AIT 1), or by a destructive thyroiditis typically occurring in normal glands (type 2 or AIT 2). Indeterminate or mixed forms are also recognized.

Thyroid antibody status, subclinical hypothyroidism, and the risk of coronary heart disease: an individual participant data analysis.

Context: Subclinical hypothyroidism has been associated with increased risk of coronary heart disease (CHD), particularly with thyrotropin levels of 10.0 mIU/L or greater. The measurement of thyroid antibodies helps predict the progression to overt hypothyroidism, but it is unclear whether thyroid autoimmunity independently affects CHD risk.

Subclinical thyroid disease.

Introduction: Subclinical thyroid disease is a common finding on testing of thyroid function and its management remains controversial.

Source Of Data: Epidemiological data from large population studies from USA and Europe.

Areas Of Agreement: There is an increased risk of progression to overt hypothyroidism or hyperthyroidism.

2012 ETA Guidelines: The Use of L-T4 + L-T3 in the Treatment of Hypothyroidism.

Background: Data suggest symptoms of hypothyroidism persist in 5-10% of levothyroxine (L-T4)-treated hypothyroid patients with normal serum thyrotrophin (TSH). The use of L-T4 + liothyronine (L-T3) combination therapy in such patients is controversial. The ETA nominated a task force to review the topic and formulate guidelines in this area.

The epidemiology of thyroid disease.

Introduction: Thyroid disorders are prevalent and their manifestations are determined by the dietary iodine availability.

Sources Of Data: Data from screening large population samples from USA and Europe.

Areas Of Agreement: The most common cause of thyroid disorders worldwide is iodine deficiency, leading to goitre formation and hypothyroidism.

Should we treat mild subclinical/mild hyperthyroidism? No.

The management of a patient with subclinical hyperthyroidism or mild thyroid over-activity is controversial. Subclinical hyperthyroidism is defined as a serum thyrotrophin (TSH) below the reference range but a normal thyroxine (T4) and triiodothyronine (T3) level in a patient who is either asymptomatic or has only non-specific symptoms. Epidemiological studies report an overall prevalence of approximately 3%, with men and women over 65 years and those in iodine deficient regions having the highest prevalence.

Iodine status of UK schoolgirls: a cross-sectional survey.

Background: Iodine deficiency is the most common cause of preventable mental impairment worldwide. It is defined by WHO as mild if the population median urinary iodine excretion is 50-99 μg/L, moderate if 20-49 μg/L, and severe if less than 20 μg/L. No contemporary data are available for the UK, which has no programme of food or salt iodination.

Subclinical hypothyroidism and the risk of coronary heart disease and mortality.

Context: Data regarding the association between subclinical hypothyroidism and cardiovascular disease outcomes are conflicting among large prospective cohort studies. This might reflect differences in participants' age, sex, thyroid-stimulating hormone (TSH) levels, or preexisting cardiovascular disease.

Objective: To assess the risks of coronary heart disease (CHD) and total mortality for adults with subclinical hypothyroidism.

Thyroid dysfunction in a UK hepatitis C population treated with interferon-alpha and ribavirin combination therapy.

Objective: To assess the incidence of thyroid dysfunction (TD) in a UK cohort of patients with hepatitis C virus (HCV) infection treated with interferon-alpha (IFNalpha) and ribavirin combination therapy (IFN/RBV).

Design, Patients And Measurements: A retrospective study of 288 patients who received IFN/RBV for HCV during a 2-year period from January 2006 was performed. Thyroid function was assessed during a 24-week or 48-week course of IFN/RBV.

How should we manage patients with mildly increased serum thyrotrophin concentrations?

A mildly increased serum thyrotrophin (TSH) is usually because of mild thyroid failure, and the most common aetiology in iodine-replete communities is chronic autoimmune thyroiditis. It is more common in women, and the prevalence increases with age in both men and women and is associated with the presence of antithyroid antibodies. The majority will have serum TSH levels between 5-10 mIU/l, normal free thyroxine (T4) levels and relatively few symptoms.

Thyroid hormone resistance.

Resistance to thyroid hormone (RTH) is a rare autosomal dominant inherited syndrome of reduced end-organ responsiveness to thyroid hormone. Patients with RTH have elevated serum free thyroxine (FT4) and free triiodothyronine (FT3) concentrations and normal or slightly elevated serum thyroid stimulating hormone (TSH) level. Despite a variable clinical presentation, the common characteristic clinical features are goitre but an absence of the usual symptoms and metabolic consequences of thyroid hormone excess.

Achieving compliance with the European Working Time Directive in a large teaching hospital: a strategic approach.

This paper describes the strategy which achieved European Working Time Directive (EWTD) compliance at the Royal Free Hampstead NHS Trust in medicine and surgery. Compliance with EWTD regulations was assessed by diary card exercise, clinical care assessed through critical incident reports, electronic handover documents and nursing reports, training opportunities assessed by unit training directors, cost controls assessed by finance department analysis, and workload assessed by staff attendance on wards, in casualty and in theatres. There was a change in focus of care to a consultant-led, specialist registrar- (SpR-)driven service extending into evenings and on weekends, coupled with a move to a multi-skilled team for night cover, and to a move from traditional on-call shifts to a full shift system across both medicine and surgery.

Epidemiology and prevention of clinical and subclinical hypothyroidism.

Iodine deficiency is the most common cause of hypothyroidism worldwide. In persons living in iodine-replete areas, causes are congenital, spontaneous because of chronic autoimmune disease (atrophic autoimmune thyroiditis or goitrous autoimmune thyroiditis [Hashimoto's thyroiditis]), or iatrogenic because of goitrogens, drugs, or destructive treatment for thyrotoxicosis. Screening for congenital hypothyroidism exists and its use prevents mental retardation.