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Importance: Thyroid hormones play a key role in modulating myocardial contractility. Subclinical hypothyroidism in patients with acute myocardial infarction is associated with poor prognosis. Objective: To evaluate the effect of levothyroxine treatment on left ventricular function in patients with acute myocardial infarction and subclinical hypothyroidism. Design, Setting, and Participants: A double-blind, randomized clinical trial conducted in 6 hospitals in the United Kingdom. Patients with acute myocardial infarction including ST-segment elevation and non-ST-segment elevation were recruited between February 2015 and December 2016, with the last participant being followed up in December 2017. Interventions: Levothyroxine treatment (n = 46) commencing at 25 µg titrated to aim for serum thyrotropin levels between 0.4 and 2.5 mU/L or identical placebo (n = 49), both provided in capsule form, once daily for 52 weeks. Main Outcomes and Measures: The primary outcome measure was left ventricular ejection fraction at 52 weeks, assessed by magnetic resonance imaging, adjusted for age, sex, type of acute myocardial infarction, affected coronary artery territory, and baseline left ventricular ejection fraction. Secondary measures were left ventricular volumes, infarct size (assessed in a subgroup [n = 60]), adverse events, and patient-reported outcome measures of health status, health-related quality of life, and depression. Results: Among the 95 participants randomized, the mean (SD) age was 63.5 (9.5) years, 72 (76.6%) were men, and 65 (69.1%) had ST-segment elevation myocardial infarction. The median serum thyrotropin level was 5.7 mU/L (interquartile range, 4.8-7.3 mU/L) and the mean (SD) free thyroxine level was 1.14 (0.16) ng/dL. The primary outcome measurements at 52 weeks were available in 85 patients (89.5%). The mean left ventricular ejection fraction at baseline and at 52 weeks was 51.3% and 53.8%, respectively, in the levothyroxine group compared with 54.0% and 56.1%, respectively, in the placebo group (adjusted difference in groups, 0.76% [95% CI, -0.93% to 2.46%]; P = .37). None of the 6 secondary outcomes showed a significant difference between the levothyroxine and placebo treatment groups. There were 15 (33.3%) and 18 (36.7%) cardiovascular adverse events in the levothyroxine and placebo groups, respectively. Conclusions and Relevance: In this preliminary study involving patients with subclinical hypothyroidism and acute myocardial infarction, treatment with levothyroxine, compared with placebo, did not significantly improve left ventricular ejection fraction after 52 weeks. These findings do not support treatment of subclinical hypothyroidism in patients with acute myocardial infarction. Trial Registration: isrctn.org Identifier: http://www.isrctn.com/ISRCTN52505169.
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Hipotireoidismo/complicações , Infarto do Miocárdio sem Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Volume Sistólico/efeitos dos fármacos , Tiroxina/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Depressão , Método Duplo-Cego , Feminino , Nível de Saúde , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/patologia , Infarto do Miocárdio sem Supradesnível do Segmento ST/fisiopatologia , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Infarto do Miocárdio com Supradesnível do Segmento ST/patologia , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Tamanho da Amostra , Tireotropina/sangue , Tiroxina/efeitos adversos , Fatores de Tempo , Reino UnidoRESUMO
OBJECTIVE: B lymphocyte activating factor (BAFF), a member of the tumour necrosis factor superfamily, is essential for B cell activation, differentiation and survival. Elevated circulating BAFF levels have been found in patients with several autoimmune conditions, including Graves' disease. In addition, BAFF gene variants have been associated with Graves' disease in a Taiwanese cohort, and with several other autoimmune conditions in non-Taiwanese populations. DESIGN AND METHODS: We performed a case-control association study to investigate two BAFF polymorphisms (rs9514828 and rs4000607) in a UK cohort of 444 patients with Graves' disease. Genotype frequencies were compared to those from 447 local controls and more than 5000 healthy controls from the Wellcome Trust case-control consortium (WTCCC2). RESULTS: There was a significant difference in the frequency of the AA genotype at rs4000607 between the Graves' disease cohort and both the local controls (P = 0.045) and the WTCCC2 controls (P = 4.56 × 10-6 ). Furthermore, the frequency of the A allele was found to be increased in the Graves' disease group compared to WTCCC2 controls (P = 0.02, OR 1.20 (95% CI 1.03-1.41). No association was observed at the rs9514828 locus. CONCLUSION: Dysfunction of the humoral immune system is an obligatory pathophysiological component of Graves' disease, hence BAFF is an excellent functional candidate gene. We have demonstrated, for the first time, a significant association of the BAFF polymorphism rs4000607 with Graves' disease in a UK cohort. Further work to elucidate the role of BAFF in the pathogenesis of Graves' disease is now warranted.
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Fator Ativador de Células B/genética , Doença de Graves/genética , Polimorfismo Genético , Alelos , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Reino UnidoRESUMO
BACKGROUND: Primary hypothyroidism is a common endocrine disorder, more so in an increasing UK ageing population. There is no qualitative research examining the older patient perspective of symptoms, treatment and self-management of hypothyroidism. OBJECTIVE: In this study we explored the experience of hypothyroidism in older people and examined how this may influence their understanding and acceptance of diagnosis, treatment with Levothyroxine and the monitoring process. DESIGN: We conducted semi-structured interviews with 18 participants aged between 80 and 93 years. Interview transcripts were analysed using a thematic approach. RESULTS: The themes involved older individuals' knowledge about symptoms, confidence in diagnosis and understanding of clinical management regimen to understand hypothyroidism. Interpretation of the themes was informed by the Health Belief Model. CONCLUSION: Our findings can help to inform the development of interventions by treating clinicians and support staff to engage older patients in the long-term management of this chronic condition.
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Doença Crônica , Hipotireoidismo/tratamento farmacológico , Autogestão , Tiroxina/uso terapêutico , Idoso de 80 Anos ou mais , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pesquisa Qualitativa , Reino UnidoRESUMO
OBJECTIVE: Hypothyroidism is more frequently diagnosed in women and older individuals. It has been suggested that the prevalence of hypothyroidism and the number of prescriptions for thyroid hormones are increasing. However, despite hypothyroidism being a common medical condition, contemporary data on prevalence, particularly across the various age groups, is limited. DESIGN: Information regarding number of individuals diagnosed with treated hypothyroidism (defined as patients prescribed levothyroxine) across ten General Practices (total population of 66 843) in the North-East of England in 2016 was obtained in an anonymized manner. Total as well as age group-specific point prevalence rates were calculated. In addition, corresponding population data for the United Kingdom were acquired, and national total and age-specific hypothyroidism prevalence rates were estimated. RESULTS: The overall prevalence of hypothyroidism in this community sample was 4.5% (n = 3004). Prevalence increased across the age groups from 0.1% in children aged 0-10 years to 15.1% in those aged more than 90 years. After adjusting for demographic differences between the North-East England and UK populations, it is estimated that the total UK-wide prevalence of hypothyroidism in 2016 is 3.6%; affecting more than 2.3 million individuals including nearly 800 000 individuals aged >70 years. CONCLUSIONS: Hypothyroidism affects millions of individuals in the UK and is currently a prevalent diagnosis in more than 1 in 10 individuals aged above 70 years. As the population ages this number is likely to increase. The clinical and economic effects of current management strategies for hypothyroidism, particularly in the older population, need to be evaluated.
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Hipotireoidismo/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Inglaterra/epidemiologia , Humanos , Lactente , Pessoa de Meia-Idade , Hormônios Tireóideos/sangue , Reino Unido/epidemiologia , Adulto JovemRESUMO
Objectives: To study the relationship between serum-free T3 (FT3), C-reactive protein (CRP) and all-cause mortality in patients with acute myocardial infarction (AMI). Design: Prospective multicentre longitudinal cohort study. Methods: Between December 2014 and December 2016, thyroid function and CRP were analysed in AMI (both ST-elevation (STEMI) and non-ST-elevation) patients from the Thyroxine in Acute Myocardial Infarction study. The relationship of FT3 and CRP at baseline with all-cause mortality up to June 2020 was assessed. Mediation analysis was performed to evaluate if CRP mediated the relationship between FT3 and mortality. Results: In 1919 AMI patients (29.2% women, mean (s.d.) age: 64.2 (12.1) years and 48.7% STEMI) followed over a median (interquartile range) period of 51 (46-58) months, there were 277 (14.4%) deaths. Overall, lower serum FT3 and higher CRP levels were associated with higher risk of mortality. When divided the patients into tertiles based on the levels of FT3 and CRP; the group with the lowest FT3 and highest CRP levels had a 2.5-fold increase in mortality risk (adjusted hazard ratio (95% CI) of 2.48 (1.82-3.16)) compared to the group with the highest FT3 and lowest CRP values. CRP mediated 9.8% (95% CI: 6.1-15.0%) of the relationship between FT3 and mortality. Conclusions: In AMI patients, lower serum FT3 levels on admission are associated with a higher mortality risk, which is partly mediated by inflammation. Adequately designed trials to explore the potential benefits of T3 in AMI patients are required.
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BACKGROUND AND AIMS: We aimed to validate a nurse-led process using electronic health records to identify those at risk of familial hypercholesterolaemia (FH) for genetic diagnosis in primary care. METHODS: Those at risk of FH were identified using searches developed and refined locally and implemented in primary care by a trained nurse; they were invited for further assessment and genetic testing if indicated. Family members at risk of FH were identified and invited for cascade testing. RESULTS: In total 94,444 patient records were screened (expected prevalence of FH (1 in 250); 377). Of 176 records which already had a diagnostic for FH, 15 had been genetically confirmed and one was undergoing DNA testing. A further 572 (0.61%) were identified as high risk of FH. After desktop screening, 113 (15%) were invited for further assessment. Of these, 73 individuals attended the primary care clinic (64%) of whom 61 (54%) underwent proband genetic testing. Pathogenic variants were detected in 22 cases (36%) and variants of unknown significance in a further 4 cases; a total of 26 probands (43%) were therefore referred for family cascade testing. CONCLUSIONS: An optimised FH identification pathway, based on the NICE CG71 recommendations for systematic searching of primary care electronic health records, can be deployed successfully in primary care settings.
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Hiperlipoproteinemia Tipo II , Medicina Estatal , Testes Genéticos , Humanos , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/epidemiologia , Hiperlipoproteinemia Tipo II/genética , Programas de Rastreamento , Atenção Primária à SaúdeRESUMO
INTRODUCTION: Serum thyroid-stimulating hormone (TSH) increases with age but target TSH is similar in younger and older hypothyroid patients on treatment. It is unknown if quality of life (QoL), hypothyroid symptoms and cardiovascular risk factors change in older hypothyroid patients treated to an age-appropriate reference range. OBJECTIVE: To assess if a higher target serum TSH of 4.01-8.0 mU/L is feasible in, and acceptable to, older treated hypothyroid patients. METHODS: A single-blind (participant) randomised controlled feasibility trial involving 48 hypothyroid patients aged ≥80 years on established and stable levothyroxine (LT4) therapy with serum TSH levels within the standard reference range (0.4-4.0 mU/L) was conducted. Standard (0.4-4.0 mU/L) or higher (4.1-8.0 mU/L) TSH target (standard TSH [ST] or higher TSH [HT] groups) LT4 for 24 weeks was administered. The outcome measures evaluated were thyroid function tests, QoL, hypothyroid symptoms, cardiovascular risk factors and serum marker of bone resorption in participants that completed the trial (n = 21/24 ST group, n = 19/24 HT group). RESULTS: At 24 weeks, in the ST and HT groups, respectively, median (interquartile range) serum TSH was 1.25 (0.76-1.72) and 5.50 (4.05-9.12) mU/L, mean (± SD) free thyroxine (FT4) was 19.4 ± 3.5 and 15.9 ± 2.4 pmol/L, and daily LT4 dose was 82.1 ± 26.4 and 59.2 ± 23.9 µg. There was no suggestion of adverse impact of a higher serum TSH in the HT group with regard to any of the outcomes assessed. CONCLUSIONS: In hypothyroid patients aged ≥80 years on LT4 therapy for 24 weeks, there was no evidence that a higher target serum TSH was associated with an adverse impact on patient reported outcomes, cardiovascular risk factors or bone resorption marker over 24 weeks. Longer-term trials assessing morbidity and mortality outcomes and health-utility in this age group are feasible and should be performed.
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OBJECTIVE: The objective of this study was to determine the impact of blood sample timing on the diagnosis of subclinical thyroid dysfunction (SCTD) and mortality in patients with acute myocardial infarction (AMI). PATIENTS, DESIGN, AND MAIN OUTCOME MEASURES: Patients with AMI had thyroid function evaluated on admission between December 2014 and December 2016 and those with abnormal serum thyrotropin (TSH) had repeat thyroid function assessed at least a week later. The association between sample timing and SCTD was evaluated by logistic regression analysis. Secondary outcomes were confirmation of SCTD on repeat testing and all-cause mortality up to June 2018. RESULTS: Of the 1806 patients [29.2% women, mean (± standard deviation) age of 64.2 (±12.1) years] analyzed, the prevalence of subclinical hypothyroidism (SCH) was 17.2% (n = 311) and subclinical hyperthyroidism (SHyper) was 1.2% (n = 22) using a uniform TSH reference interval. The risk of being diagnosed with SCTD varied by sample timing in fully-adjusted models. The risk of SCH was highest between 00.01 and 06.00 hours and lowest between 12.01 and 18.00 hours, P for trend <.001, and risk of SHyper was highest between 12.01 hours and 18.00 hours and lowest between 00.01 hours and 06.00 hours. Furthermore, time of the initial sample was associated with the risk of remaining in a SCH state subsequently. Mortality in SCH patients was not elevated when a uniform TSH reference interval was utilized. However, when time period-specific TSH reference ranges were utilized, the mortality risk was significantly higher in SCH patients with HR (95% CI) of 2.26 (1.01-5.19), P = .04. CONCLUSIONS: Sample timing impacts on the diagnosis and prognosis of SCH in AMI patients. If sample timing is not accounted for, SCH is systemically misclassified, and its measurable influence on mortality is lost.
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Infarto do Miocárdio/mortalidade , Manejo de Espécimes/normas , Doenças da Glândula Tireoide/mortalidade , Doença Aguda , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/etiologia , Doenças da Glândula Tireoide/metabolismo , Testes de Função Tireóidea , Fatores de TempoRESUMO
CONTEXT: Subclinical hypothyroidism (SCH) is defined as raised serum TSH levels with circulating thyroid hormones within the reference range. It is uncertain whether treatment of SCH with L-thyroxine improves cardiovascular (CV) risk factors and quality of life. OBJECTIVE: The objective of the study was to assess CV risk factors and patient-reported outcomes after treatment. DESIGN: This was a randomized, double-blind, crossover study of L-thyroxine and placebo. SETTING: The study was conducted with community-dwelling patients. PATIENTS: One hundred patients [mean age (sd) 53.8 (12) yr, 81 females] with SCH [mean TSH 6.6 (1.3) mIU/liter] without previously treated thyroid or vascular disease. INTERVENTION: Intervention consisted of 100 microg L-thyroxine or placebo daily for 12 wk each. MEASUREMENTS: Primary parameters were total cholesterol (TC) and endothelial function [brachial artery flow-mediated dilatation (FMD)], an early marker of atherosclerosis. Patient-reported outcomes were also assessed. RESULTS: L-thyroxine treatment reduced TC (vs. placebo) from 231.6 to 220 mg/dl, P < 0.001; low-density lipoprotein cholesterol from 142.9 to 131.3 mg/dl, P < 0.05; waist to hip ratio from 0.83 to 0.81, P < 0.006; and improved FMD from 4.2 to 5.9%, P < 0.001. Multivariate analysis showed that increased serum free T(4) level was the most significant variable predicting reduction in TC or improvement in FMD. Furthermore, the symptom of tiredness improved on L-thyroxine therapy, but other patient-reported outcomes were not significantly different after correction for multiple comparisons. CONCLUSION: SCH treated by L-thyroxine leads to a significant improvement in CV risk factors and symptoms of tiredness. The CV risk factor reduction is related to the increased level of achieved free T(4) concentration.
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Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Endotélio Vascular/efeitos dos fármacos , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/psicologia , Qualidade de Vida , Tiroxina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Índice de Massa Corporal , Peso Corporal/fisiologia , Artéria Braquial/diagnóstico por imagem , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiologia , Colesterol/sangue , Estudos Cross-Over , Método Duplo-Cego , Feminino , Nível de Saúde , Humanos , Hipotireoidismo/complicações , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Tamanho da Amostra , Resultado do Tratamento , Ultrassonografia , Vasodilatação/fisiologiaRESUMO
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. METHODS: A 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. RESULTS: Fifteen 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 REGISTRATION: ISRCTN Number: 16043724 Registered 22 June 2012 Clinicaltrial.gov Number: NCT01647750 EudraCT Number: 2011-004425-27.
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OBJECTIVE: Sub-clinical hypothyroidism (SCH) is a common disorder. People with this condition may have symptoms which could affect their perception of health. Therefore, the perceived health status of people with SCH was assessed and compared with population-matched norms. DESIGN: A prospective cross-sectional survey. METHODS: Seventy-one adults with SCH, age range 18-64 years were studied. Perceived health status was measured by the Short Form-36 (SF-36) version 2 questionaire, which has been validated in a UK population setting. The SF-36 has eight scales measuring physical functioning, role physical, bodily pain, general health, vitality, social functioning, role emotional and mental health. Their SF-36 scores were compared with UK normative data after matching for age and sex and are reported as z-scores. RESULTS: Scores of all eight SF-36 scales were significantly lower in people with SCH compared with the normative population. A negative score (compared with zero of the normative population) indicates worse health status. The most significantly impaired aspects of health status were vitality and role limitations due to physical problems (role physical scale) with z-scores (95% confidence intervals) of -1.01 (-0.74 to -1.29) and -0.73 (-0.43 to -1.04) respectively. Thyroid autoimmunity did not influence the results. CONCLUSION: Perceived health status is significantly impaired in people with SCH when compared with UK normative population scores. This needs to be taken into consideration by clinicians when managing patients with this disease.
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Atitude Frente a Saúde , Nível de Saúde , Hipotireoidismo/fisiopatologia , Hipotireoidismo/psicologia , Adulto , Coleta de Dados , Feminino , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Dor/psicologia , Percepção , Comportamento Social , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Cardiac disease is the most common cause of morbidity and mortality in the United Kingdom. Even minor changes in thyroid hormone concentration may impact adversely on the cardiovascular system. Subclinical hypothyroidism (SCH) after admission for an acute cardiac problem has been associated with an increase in cardiac mortality and overall death. We have designed protocols for a prospective observational study to assess the association of thyroid function at the time of acute myocardial infarction (AMI) with cardiovascular outcomes, and a double-blinded randomised placebo-controlled trial of levothyroxine to evaluate its effect on LV function and vascular health. METHODS/DESIGN: ThyrAMI 1: This will be a prospective longitudinal observational study of patients with AMI that will be followed for 24 months to study the association between thyroid status at the time of AMI (within 24 hours of diagnosis) with vascular outcomes. ThyrAMI 2: This will be a prospective double-blinded randomised placebo-controlled trial of levothyroxine of 12 months duration in patients with AMI and SCH. SETTING: Patients will be recruited from five hospitals in the North East of England. PARTICIPANTS: One hundred patients with thyroid function tests within the subclinical hypothyroid range upon admission with an AMI and no previous history of thyroid disease. INTERVENTION: Levothyroxine will be administered at a starting dose of 25 mcg once daily, which will be increased at intervals if needed to maintain a TSH level between 0.4 to 2.5 mU/L, versus a placebo. RANDOMISATION: Participants will be randomized with a computerised randomisation algorithm, stratified by type of MI (NSTEMI versus STEMI), in a 1:1 ratio to levothyroxine therapy or placebo (as container or bottle numbers), starting within 21 (+/- 7) days of AMI. BLINDING: Assignment to either the LT4 or placebo arm will be double-blinded. OUTCOMES: The outcome will be the effect of levothyroxine on ventricular function, endothelial function and blood coagulability and rheology. DISCUSSION: There is evidence to suggest that treatment of SCH can improve cardiovascular parameters. Therefore, ThyrAMI 1 and ThyrAMI 2 will be the first trials investigating SCH in AMI to give a better insight into whether thyroid hormone levels are a key target for improving cardiovascular outcomes. TRIAL REGISTRATION: ISRCTN number: ISRCTN52505169 . Date of registration: 09/01/2015.
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Hipotireoidismo/complicações , Hipotireoidismo/tratamento farmacológico , Infarto do Miocárdio/complicações , Tiroxina/uso terapêutico , Doenças Assintomáticas , Biomarcadores/sangue , Protocolos Clínicos , Método Duplo-Cego , Inglaterra , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Estudos Longitudinais , Masculino , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Estudos Prospectivos , Projetos de Pesquisa , Testes de Função Tireóidea , Tireotropina/sangue , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: The population of the UK is ageing. There is compelling evidence that thyroid stimulating hormone distribution levels increase with age. Currently, in UK clinical practice elderly hypothyroid patients are treated with levothyroxine to lower their thyroid stimulating hormone levels to a standard non-age-related range. Evidence suggests that mortality is negatively associated with thyroid stimulating hormone levels. We report the protocol of a feasibility study working towards a full-scale randomized controlled trial to test whether lower dose levothyroxine has beneficial cardiovascular outcomes in the oldest old. METHODS/DESIGN: SORTED is a mixed methods study with three components: SORTED A: A feasibility study of a dual-center single-blinded randomized controlled trial of elderly hypothyroid patients currently treated with levothyroxine. SETTING: Patients will be recruited from 20 general practices and two hospital trust endocrine units in Northumberland, Tyne and Wear. PARTICIPANTS: Target recruitment of 50 elderly hypothyroid patients currently treated with levothyroxine, identified in both primary and secondary care settings. INTERVENTION: Reduced dose of levothyroxine to achieve an elevated serum thyroid stimulating hormone (target range 4.1 to 8.0 mU/L) versus standard levothyroxine replacement (target range 0.4 to 4.0 mU/L). RANDOMIZATION: Using random permuted blocks, in a ratio of 1:1, randomization will be carried out by Newcastle Clinical Trials Unit. OUTCOMES: Study feasibility (recruitment and retention rates and medication compliance), acceptability of the trial design, assessment of mobility and falls risk, and change in cardiovascular risk factors. SORTED B: Qualitative study using in-depth interviews to understand patients' willingness to take part in a randomized controlled trial and participants' experience of the intervention. SORTED C: Retrospective cohort study of 400 treated hypothyroid patients aged 80 years or over registered in 2008 in primary care practices, studying their 4-year cardiovascular outcomes to inform the power of SORTED II. DISCUSSION: This is a study to evaluate the feasibility of conducting a randomized controlled trial in elderly hypothyroid patients in general practice and hospital settings. The results will inform the design of the definitive SORTED II trial to evaluate the effects of lower dose thyroxine in elderly hypothyroid patients. TRIAL REGISTRATION: Current Controlled Trials ISRCTN16043724.
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Terapia de Reposição Hormonal , Hipotireoidismo/tratamento farmacológico , Projetos de Pesquisa , Tiroxina/administração & dosagem , Fatores Etários , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Protocolos Clínicos , Estudos de Viabilidade , Medicina Geral , Conhecimentos, Atitudes e Prática em Saúde , Hospitais , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Retrospectivos , Método Simples-Cego , Tireotropina/sangue , Fatores de Tempo , Resultado do Tratamento , Reino UnidoRESUMO
CONTEXT: Subclinical hypothyroidism (SCH) is associated with cardiovascular (CV) risk factors, and possibly CV disease. However, its management remains controversial. Endothelial progenitor cells (EPC), expressing both endothelial and stem cell markers, are known to offer a novel CV risk marker. OBJECTIVE: The aim of the study was to ascertain whether EPC count or function is reduced in SCH and whether it improves with T(4) therapy. DESIGN AND INTERVENTION: EPC were studied in peripheral blood by fluorescence-activated cell sorter and following in vitro cultures before and after T(4) together with CV risk factors in 20 SCH and healthy controls (HC). MAIN OUTCOME MEASURE: EPC count was measured at baseline and after T(4) replacement in SCH. RESULTS: EPC count was significantly reduced in SCH compared to HC: median (range)-CD133+/VEGFR-2+, 0.09 (0.02-0.44) vs. 0.47 (0.17-2.12), P < 0.001; CD34+/VEGFR-2+, 0.10 (0.04-0.46) vs. 0.39 (0.11-2.13), P < 0.001; whereas EPC function was similar. There was a significant positive correlation between CD133+/VEGFR-2+ with free T(4) levels (r = 0.38; P = 0.02); high-density lipoprotein cholesterol levels (r = 0.51; P = 0.001); and negative correlation with TSH concentrations (r = -0.64; P < 0.001). After adjustment for conventional CV risk factors, SCH predicted lower EPC count, beta coefficient/P value: CD133+/VEGFR-2+ (-0.77/<0.001), and CD34+/VEGFR-2+ (-0.71/<0.001). In SCH participants, EPC count increased and was similar to HC after T(4); CD133+/VEGFR-2+, 0.32 (0.03-0.94) vs. 0.09 (0.02-0.44), P < 0.001; and CD34+/VEGFR-2+, 0.26 (0.06-0.88) vs. 0.10 (0.04-0.46), P < 0.001. CONCLUSION: SCH predicted lower EPC count, which improved with T(4) treatment, independent of other CV risk factors, providing additional evidence that T(4) replacement may improve CV risk in SCH.