Increasing prevalence and incidence of thyroid disease in Tayside, Scotland: The Thyroid Epidemiology Audit and Research Study (TEARS)

ArticleinClinical Endocrinology 68(2):311-6 · February 2008with18 Reads
DOI: 10.1111/j.1365-2265.2007.03051.x · Source: PubMed
We aimed to describe the changing incidence of thyroid disease in a population-based study in Tayside, Scotland (population 390 000) between 1994 and 2001. A retrospective, data-linkage, population-based study measuring the incidence and prevalence of thyroid disease. All patients with newly diagnosed, treated and stable thyroid disease in Tayside were identified by electronic linkage of six datasets, including all regional biochemistry data, hospital admissions, deaths and a thyroid follow-up register. The overall prevalence of thyroid dysfunction has increased from 2.3% to 3.8% (1994-2001). The prevalence of ever having had hyperthyroidism increased from 0.86% to 1.26% in females and 0.17% to 0.24% in males (P < 0.0001 for both). The standardized incidence of hyperthyroidism increased from 0.68 to 0.87 per 1000 females/year, representing a 6.3% annual increase (P < 0.0001). The prevalence of primary hypothyroidism increased from 3.12% to 5.14% in females and 0.51% to 0.88% in males (P < 0.0001 for both). The standardized incidence of primary hypothyroidism did not change and varied between 3.90 and 4.89 per 1000 females/year over the 8 years. Incidence of hypothyroidism in males increased from 0.65 to 1.01 per 1000 males/year (P = 0.0017). Mean age at diagnosis of primary hypothyroidism declined in females from 1994 to 2001. The prevalence of primary hypothyroidism and previous hyperthyroidism has increased in Tayside, Scotland. This is partly due to an increasing incidence of disease, increased ascertainment and earlier diagnosis of disease. This will result in an increased workload for endocrinologists and general practitioners.
    • "Treatment with the synthetic form of thyroxine (Levothyroxine or LT4) is the treatment of choice in these patients and patients are generally managed in primary care. LT4 is prescribed to 3–4 % of the general population and its use is increasing [3][4][5] . Thyroid function changes with age and several reports suggest that the upper limit of the TSH reference range increases with age [6][7][8][9][10]. "
    [Show abstract] [Hide abstract] ABSTRACT: Background Hypothyroidism is a common condition, particularly in the older population. Thyroid hormone requirements change with age and serum TSH levels also alter, especially in older patients. However, in practice laboratory reference ranges for thyroid function are not age-specific and treatment in older patients aims to achieve a similar target thyroid function level as younger age groups. MethodsA dual centre, single blind, randomised controlled trial was conducted to determine the feasibility of a future definitive RCT in hypothyroid individuals aged 80 years or older who were treated with levothyroxine. Potential participants were identified from 17 research-active GP practices (n = 377), by opportunistic invitations (n = 9) or in response to publicity (n = 4). Participants were randomly allocated to either usual (0.4–4.0 mU/L) or a higher (4.1–8.0 mU/L) target serum TSH range. Information on participants’ willingness to enter the trial, acceptability of study design, length of time to complete recruitment and dose titration strategy was collected. ResultsFifteen percent (57/390) of potentially eligible hypothyroid individuals consented to participate in this trial and 48 were randomised to trial medication for 24 weeks, giving a recruitment rate of 12 %. Recruitment averaged 5.5 participants per month over approximately 9 months. Eight participants withdrew (3/24 and 5/24 in the usual and higher TSH arms, respectively) with the commonest reason cited (5 patients) being tiredness. Interestingly, 3/5 participants withdrew from the site that required a visit to a Research Facility whereas only 5/43 participants withdrew from the site that offered home visits. In the higher TSH arm, of those participants who completed the study, approximately half of participants (10/19) reached target TSH. Conclusions It is feasible to perform a randomised controlled trial of thyroid hormones in hypothyroid patients aged 80 or older. A definitive trial would require collaboration with a large number of General Practices and the provision of home visits to achieve recruitment to time and target. Power calculations should take into account that approximately 12 % of those approached will be randomised and 1 in 6 participants are likely to withdraw from the study. Finally, several dose adjustments may be required to achieve target serum TSH levels in this age group. Trial registrationISRCTN Number: 16043724 Registered 22 June Number: NCT01647750EudraCT Number: 2011-004425-27
    Full-text · Article · Dec 2016
    • "Given the prevalence and severity of different forms of thyroid disease, the yearly number of tests performed worldwide is huge [1][2][3][4]. Clinicians mainly rely on the analysis of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) for the diagnosis of thyroid dysfunction and patient follow-up. The frequency of thyroid function testing translates in an enormous impact of the disease on the healthcare system. "
    [Show abstract] [Hide abstract] ABSTRACT: Clinicians diagnose thyroid dysfunction based on TSH and FT4 testing. However, the current lack of comparability between assays limits the optimal use of laboratory data. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) gave a mandate to the Committee for Standardization of Thyroid Function Tests (C-STFT) to resolve this limitation by standardization. Recently, the Committee members and their partners felt ready to set the step towards the technical recalibration. However, before implementation, they were furthered by the Food and Drugs Administration (FDA) to develop a tool to assess the sustainability of the new calibration basis. C-STFT began to use 2 online applications, i.e., the "Percentiler" and "Flagger", with the intention to assess their utility for this purpose. The tools monitor the course of instrument-specific moving medians of outpatient results (Percentiler) and flagging rates (Flagger) from data of individual laboratories grouped by instrument/assay peer. They additionally document the mid- to long-term medians, hence, are quality indicators of stability of performance of both laboratories and peers/assays. Here, the first experiences built up in the pre-standardization phase are reported. They suggest the suitability of both applications to document the sustainability of the calibration basis in the post-standardization phase.
    Full-text · Article · Apr 2016
    • "Subclinical hypothyroidism (SCH), which is defined as an isolated elevation of thyroid-stimulating hormone (TSH) levels with a normal free thyroxine (fT4) level, is a relatively common disorder. Most experts agree that SCH represents early, mild thyroid failure [1] and this issue is becoming increasingly recognized because the performance of thyroid function tests have substantially increased in primary care settings [2] . Despite the intuitive appeal of the relationship between elevated TSH levels or SCH and adverse cardiovascular (CV) outcomes, it remains unclear whether variations in thyroid hormone levels within the normal range are also associated with mortality end- points [3]. "
    [Show abstract] [Hide abstract] ABSTRACT: Subclinical hypothyroidism (SCH) is a common disorder that is characterized by elevated thyroid-stimulating hormone (TSH) levels in conjunction with free thyroxine (fT4) concentrations within the normal reference range. Thyroid hormones are known to affect the heart and vasculature and, as a result, the impact of SCH on the cardiovascular (CV) system has recently become an important topic of research. Strong evidence points to a link between SCH and CV risk factors such as alterations in blood pressure, lipid levels, and atherosclerosis. Additionally, accumulating evidence indicates that SCH is associated with metabolic syndrome and heart failure. The present review proposes that SCH may be a potentially modifiable risk factor of CV disease and mortality. However, large-scale clinical trials with appropriate power investigating the risks and benefits of SCH treatment are required to determine whether these benefits can be achieved with levothyroxine therapy.
    Full-text · Article · Aug 2015
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