亚临床甲状腺功能异常与心血管疾病的关系

临床研究显示,亚临床甲状腺功能异常与心血管疾病之间存在密切的关系.亚临床甲状腺功能减退通常伴有血脂异常、高凝状态、纤维蛋白溶解活性减低等心血管疾病危险因素,其与动脉粥样硬化、冠心病和心血管死亡的风险显著相关.另一方面,亚临床甲状腺功能亢进与心房颤动发生风险显著相关,但与心血管死亡风险的相关性尚不清楚.对于亚临床甲状腺功能异常进行治疗是否能够带来心血管获益,目前尚无确切结论.     

亚临床甲状腺功能异常与心血管疾病的关系

临床研究显示,亚临床甲状腺功能异常与心血管疾病之间存在密切的关系.亚临床甲状腺功能减退通常伴有血脂异常、高凝状态、纤维蛋白溶解活性减低等心血管疾病危险因素,其与动脉粥样硬化、冠心病和心血管死亡的风险显著相关.另一方面,亚临床甲状腺功能亢进与心房颤动发生风险显著相关,但与心血管死亡风险的相关性尚不清楚.对于亚临床甲状腺功能异常进行治疗是否能够带来心血管获益,目前尚无确切结论.     

增龄性亚临床甲状腺功能异常在抗衰老医学中的重要性

<正>神经和内分泌系统是人体两大中枢调控系统,二者相互协调,以维持人体内环境的平衡。甲状腺素分泌和释放受下丘脑-垂体-甲状腺轴调控,互为反馈,如亚临床甲状腺功能减退(及亢进)与促甲状腺释放激素(TSH)血清水平的升高(或降低)的关系。增龄性临床前甲状腺功能异常(又称亚临床甲状腺功能病STD)包括亚临床甲状腺功能减退(SHypo)、亚临床甲状腺功能亢进(SHyper)与一些疾病的相关关系必须给予重视。     

成人非老年亚临床甲状腺功能异常的管理

亚临床甲状腺功能异常在人群中普遍常见,其诊断依赖于实验室检查结果,分为亚临床甲状腺功能减退症和亚临床甲状腺功能亢进症.文章仅涉及成人非老年内源性亚临床甲状腺功能异常,结合近年国内外多个临床指南,重点介绍亚临床甲状腺功能减退和亚临床甲亢非妊娠和妊娠人群相关的管理内容.文章管理建议仅针对非老年(70岁以下的亚临床甲减和65...     

亚临床甲状腺疾病

亚临床甲状腺疾病是指无或有轻微甲状腺疾病相关症状、仅在实验室检查中或通过影像学手段发现的甲状腺异常，包括甲状腺意外结节、亚临床甲状腺功能亢进、轻微甲状腺功能减退先进。它们可影响正常的生理及代谢过程，部分患者可出现相关临床症状。亚临床甲状腺疾病应视患者的具体情况进行个体化处置。     

亚临床甲状腺功能减退症与心脏病

亚临床甲状腺功能减退症影响心血管系统,增加冠心病风险的报道近年增多,本文总结流行病学调查认为亚临床甲状腺功能减退症是冠心病的独立危险因素;并从影响血凝、血脂、脂蛋白a、C反应蛋白和同型半胱氨酸等指标探讨其增加血栓性疾病的风险因素;亚临床甲状腺功能减退症还会影响心脏传导功能并见心肌功能受损,以及L—T4激素替代治疗等方面,综述亚临床甲状腺功能减退症对心血管系统的影响。鉴于亚临床甲状腺功能减退症的病理改变具有可逆性,评估亚临床甲状腺功能减退症病人L—T4治疗潜在的益处和危险是必要的。这将为临床医生进行针对性的治疗提供依据。     

亚临床甲状腺疾病

亚临床甲状腺疾病是指无或有轻微甲状腺疾病相关症状、仅在实验室检查中或通过影像学手段发现的甲状腺异常 ,包括甲状腺意外结节、亚临床甲状腺功能亢进、轻微甲状腺功能减退等。它们可影响正常的生理及代谢过程 ,部分患者可出现相关临床症状。亚临床甲状腺疾病应视患者的具体情况进行个体化处置     

妊娠中晚期孕妇甲状腺功能异常和自身抗体筛查的研究

目的 研究妊娠中晚期孕妇甲状腺功能异常及自身抗体阳性的患病率,探讨在孕妇群体中进行甲状腺筛查的必要性.方法 研究对象为2006年6月至2008年2月期间在上海交通大学附属第一人民医院就诊的妊娠中晚期孕妇,以问卷调查方式采集病史资料,根据孕妇是否有甲状腺疾病既往史、家族史或其他相关疾病既往史,分为高甲状腺疾病风险组(高风险组)和低甲状腺疾病风险组(低风险组).对所有孕妇检测血清FT3、FT4、TSH、甲状腺过氧化物酶抗体(TPOAb)和促甲状腺激素受体抗体水平.结果 共筛查孕妇2 101名,发现有各种甲状腺功能异常或甲状腺抗体阳性712例(33.89％).高风险组孕妇中有较高比例的甲状腺功能异常,而低风险组1 983名孕妇中亦有2.27％(45例)诊断为甲状腺功能减退,11.60％(230例)为亚临床甲状腺功能减退,0.20％(4例)为甲状腺功能亢进,1.06％(21例)为亚临床甲状腺功能亢进,6.45％(128例)为低甲状腺素血症,10.74％(213例)甲状腺功能正常但TPOAb阳性.在TPOAb阳性孕妇中,甲状腺功能异常者更多见.其中79.74％甲状腺功能异常或TPOAb阳性孕妇经本次筛查发现.结论 妊娠中晚期孕妇中进行甲状腺筛查可发现33.89％孕妇存在甲状腺功能异常或TPOAb阳性,TPOAb阳性孕妇出现甲状腺功能异常的患病率增加.如果仅对高风险孕妇进行甲状腺筛查,则可能导致高达79.74％患者漏诊.     

亚临床甲状腺功能紊乱对急性心力衰竭患者远期预后的影响

目的评价亚临床甲状腺功能紊乱对急性心力衰竭患者远期预后的影响。方法纳入420例急性心力衰竭(AHF)患者。入院24 h内测定甲状腺激素、脑利钠肽(BNP)并行超声心动图检查。应用Logistic回归和Cox风险模型分析亚临床甲状腺功能紊乱与全因死亡的关系。结果在6~49个月随访期间,119例(28.3%)患者死亡,甲状腺功能正常组与亚临床甲状腺功能减退(SHypo)组、亚临床甲状腺功能亢进(SHyper)组的全因死亡率存在差异(分别为26.5%、51.1%、34.5%,log-rankχ~2=6.172,P=0.046)。多因素Cox风险模型分析显示,年龄、BNP、左室射血分数、甲状腺激素、游离甲状腺激素、SHypo(危险比:1.147,95%CI:0.971~1.352,P=0.012)是AHF患者全因死亡的预测因素。血清三碘甲状腺原氨酸,游离三碘甲状腺原氨酸和SHyper不是全因死亡的预测因素。结论 SHypo是AHF患者的全因死亡独立预测因素,而SHyper不是全因死亡预测因素。     

老年人甲状腺功能异常与心血管疾病

甲状腺功能异常与心血管疾病密切相关。老年人促甲状腺激素分布曲线向高水平方向偏移,因此,需应用年龄特异的参考范围判断甲状腺功能状态。近来,亚临床甲状腺疾病日益得到重视。研究表明亚临床甲状腺功能亢进（亚甲亢）可引起心脏结构和功能的改变,可引起房颤的发生率增加。而亚临床甲状腺功能减退（亚甲减）可能是心力衰竭、缺血性心脏病、全因死亡的一个潜在危险。异常甲状腺功能经纠正后,与甲亢和甲减相关的心血管疾病可得到缓解。基于老老年患者中亚临床甲减可能有保护作用,因此,亚临床甲状腺功能异常对心血管疾病的影响以及何种患者经过治疗可以获益,需要更多的循证医学的证据用以指导临床实践。     

Cardiovascular risk with subclinical hyperthyroidism and hypothyroidism: pathophysiology and management

Previous studies have suggested that subclinical thyroid dysfunction, as manifested by abnormalities in thyroid-stimulating hormone (TSH) levels, are associated with detrimental effects on the cardiovascular system. Subclinical hypothyroidism is characterized by abnormal lipid metabolism, cardiac dysfunction, diastolic hypertension conferring an elevated risk of atherosclerosis, and ischemic heart disease. Similarly, patients with subclinical hyperthyroidism have nearly 3 times the likelihood of atrial fibrillation over a 10-year follow-up interval, raising the question of whether patients with subclinical hyperthyroidism should be treated to prevent atrial fibrillation. A single measurement of low serum TSH in individuals aged 60 years or older has been reported to be associated with increased mortality from all causes and in particular from circulatory and cardiovascular disease in a 10-year follow-up study. Subclinical thyroid dysfunction is currently the subject of numerous studies and remains controversial, particularly as it relates to cardiovascular morbidity and mortality and clinical applications.     

Pericardial effusion associated with subclinical hypothyroidism

Previous studies have suggested that subclinical thyroid dysfunction, as manifested by abnormalities in thyroid-stimulating hormone (TSH) levels, are associated with detrimental effects on the cardiovascular system. Subclinical hyperthyroidism is an increasingly recognized entity that is defined as a normal serum free thyroxine and free triiodothyronine levels with a thyroid-stimulating hormone level suppressed below the normal range and usually undetectable. It has been reported that subclinical hyperthyroidism is not associated with coronary heart disease or mortality from cardiovascular causes but it is sufficient to induce arrhythmias including atrial fibrillation and atrial flutter. It has also been reported that increased factor X activity in patients with subclinical hyperthyroidism represents a potential hypercoagulable state. Subclinical hypothyroidism is defined by elevated serum levels of TSH with normal levels of free thyroid hormones. Subclinical hypothyroidism is characterized by abnormal lipid metabolism, cardiac dysfunction, diastolic hypertension conferring an elevated risk of atherosclerosis, and ischemic heart disease. It has been reported that sub-clinical hypothyroidism is associated with both, a significant risk of coronary heart disease at baseline and at follow-up and that mortality from cardiovascular causes is significantly higher at follow-up. However subclinical thyroid dysfunction is currently the subject of numerous studies and remains controversial, particularly as it relates to cardiovascular morbidity and mortality and clinical applications. Pericardial effusion can be present in systemic disorders including hypothyroidism. We present a case of subclinical hypothyroidism in a 41-year-old Italian woman with an ubiquitary pericardial effusion. Also this case focuses attention on subclinical hypothyroidism.     

Subclinical hyperthyroidism in patients with type 2 diabetes

Both subclinical hyperthyroidism and type 2 diabetes (T2D) have been associated with an increase in cardiovascular disease risk and mortality. We aimed to assess the prevalence of newly diagnosed subclinical hyperthyroidism in a cohort of patients with T2D, and also to analyse the relationships between diabetes-related characteristics and the presence of subclinical hyperthyroidism. 933 diabetic patients without previous history of thyroid disease (45.4% females, mean age 66.3 years, median duration of diabetes 10 years) were evaluated. A sample of 911 non-diabetic subjects without known thyroid dysfunction was studied as control group. Serum concentrations of thyrotropin were measured in all subjects. Subclinical hyperthyroidism was present in 4.3% of female and 3.5% of male diabetic patients. Relative risk was significant only for the female gender (OR 3.69, 95% CI 1.56-8.71). In comparison with diabetic patients without thyroid hyperfunction, patients with subclinical hyperthyroidism were older, had longer duration of diabetes, showed lower fasting glucose levels, had greater proportion of goitre and diet therapy, and had lower proportion of treatment with oral agents. Logistic regression analysis showed that age and the presence of goitre were significantly related to subclinical hyperthyroidism in patients with T2D. The risk for subclinical hyperthyroidism is increased in women with T2D. Advanced age and the presence of goitre are significantly and independently related with the presence of subclinical hyperthyroidism in diabetic population.     

Relationship of low-density lipoprotein (LDL) particle size to thyroid function status in Koreans

Objective  Dyslipidaemia is a well-known manifestation of thyroid dysfunction. Recently, small low-density lipoprotein (LDL) particle size has been linked with development of cardiovascular disease. To better understand the effects of thyroid dysfunction on the development of cardiovascular disease, we examined LDL particle size and lipid profiles in subjects with different thyroid function.
Methods  Included were 46 patients with overt hypothyroidism, 57 patients with subclinical hypothyroidism, 46 patients with overt hyperthyroidism, 51 patients with subclinical hyperthyroidism, and 110 age- and sex-matched healthy control subjects. We measured LDL particle size and lipid profiles in these subjects.
Results  No significant differences were found in LDL particle size between the groups with different thyroid function. Serum total cholesterol and LDL-cholesterol levels were significantly higher in the cases of hypothyroidism than in the cases of hyperthyroidism and the healthy control subjects. Serum triglyceride levels were higher in subjects with overt hypothyroidism than in those with overt hyperthyroidism or healthy control subjects.
Conclusions  LDL particle size, the emerging risk factor for atherosclerosis, did not appear to be significantly affected by the degree of thyroid dysfunction. Increased risk of atherosclerosis in hypothyroidism does not appear to be associated with LDL particle size, the non-traditional cardiovascular risk factor.     

Cardiovascular morbidity and mortality in thyroid dysfunction

This review summarizes present knowledge from clinical and epidemiological studies with respect to cardiovascular complications in thyroid disorders, focusing on cardiovascular morbidity and mortality. Consistently, good evidence exists for an increased cardiovascular morbidity in overt hyperthyroidism, and an association with predictors of cardiovascular mortality like ventricular hypertrophy, ventricular dysfunction, and atrial fibrillation. As for subclinical hyperthyroidism evidence is conclusive only with respect to an up to 5.2-fold elevated risk for atrial fibrillation. The cardiovascular risk profile of overt hypothyroidism is characterized mainly by risk factors of atherosclerosis such as hypercholesterolemia and hypertension, but also by possible development of heart failure. In contrast, data on such parameters are inconsistent for subclinical hypothyroidism. Although many of these cardiovascular alterations may hypothetically worsen prognosis, results from cohort and retrospective studies do not consistently point towards increased mortality. Only for overt hyperthyroidism an up to 1.7 fold elevated risk for cardiovascular diseases and up to 1.7 fold increased cardiovascular mortality rates have been demonstrated. However, the evidence for similarly increased cardiovascular morbidity and mortality rates in subclinical hyperthyroidism and hypothyroidism is inconclusive, and the evidence is non-existent for overt hypothyroidism. Further randomized clinical studies and population-based cohort-studies are required and should consider major cardiovascular risk factors and adverse cardiovascular events and mortality.     

Thyroid hormone in health and disease

Thyroid disease is common, affecting around 2% of women and 0.2% of men in the UK. Our understanding of the effects of thyroid hormones under physiological circumstances, as well as in pathological conditions, has increased dramatically during the last two centuries and it has become clear that overt thyroid dysfunction is associated with significant morbidity and mortality. Both hypo-and hyperthyroidism and their treatments have been linked with increased risk from cardiovascular disease and the adverse effects of thyrotoxicosis in terms of osteoporosis risk are well established. Although the evidence suggests that successful treatment of overt thyroid dysfunction significantly improves overall survival, the issue of treating mild or subclinical hyper- and hypothyroidism remains controversial. Furthermore, the now well-established effects of thyroid hormones on neurodevelopment have sparked a whole new debate regarding the need to screen pregnant women for thyroid function abnormalities. This review describes the current evidence of the effects of thyroid hormone on the cardiovascular, skeletal and neurological systems, as well as the influence of thyroid diseases and their treatments on the development of malignancy. Furthermore we will describe some recent developments in our understanding of the relationship between thyroid status and health.     

Recognition and management of cardiovascular disease related to thyroid dysfunction

Hypothyroidism and hyperthyroidism are both associated with clinically significant cardiovascular derangements. In hypothyroidism, these include pericardial effusion, heart failure, and the complex interrelationship between hypothyroidism and ischemic heart disease. Cardiovascular disorders associated with hyperthyroidism include atrial tachyarrhythmias, mitral valve dysfunction, and heart failure. Although these usually occur in individuals with intrinsic heart disease, thyroid dysfunction alone rarely causes serious but reversible cardiovascular dysfunction. Patients with commonly encountered cardiac disorders, e.g., idiopathic cardiomyopathy and atrial fibrillation, should be screened for potentially contributing subclinical thyroid diseases. In patients with heart failure and hypothyroidism, initial management should focus on diagnosis and optimal management of any primary cardiac disease, whereas in hyperthyroidism, aggressive measures to control excess thyroid hormone action should generally have the highest priority.