Division of Clinical Laboratory Science, School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
J Clin Endocrinol Metab. 2013 Jun;98(6):2308-17. doi: 10.1210/jc.2012-4065. Epub 2013 Mar 28.
Subclinical hypothyroidism (SCH) has been associated with an increased risk for cardiovascular disease. However, few studies have specifically examined the association between SCH and myocardial infarction (MI), and the relationship is poorly understood.
The purpose of this study was to evaluate incident MI risk in relation to SCH and severities of SCH among postmenopausal women.
We used a population-based nested case-cohort design within the Women's Health Initiative observational study to examine the association between SCH and incident first-time MI risk among postmenopausal women in the United States. SCH was assessed using blood specimens collected at baseline. Participants presenting with normal free T4 levels and with thyrotropin levels of greater than 4.68-6.99 mU/L or 7.00 mU/L or greater were defined as having mild SCH or moderate/severe SCH, respectively. MI cases were centrally adjudicated by trained Women's Health Initiative staff. The primary analysis included 736 incident MI cases and 2927 randomly selected subcohort members. Multivariable adjusted Cox-proportional hazard models were used to assess MI risk in relation to SCH.
Compared with euthyroid participants, the multivariable adjusted hazard ratio (HR) for participants with any SCH was 1.05 [95% confidence interval (CI) 0.77-1.44]. HRs for participants with mild SCH, moderate/severe SCH, and moderate/severe SCH and the presence of antithyroid peroxidase antibodies (TPOAb) were 0.99 (95% CI 0.67-1.46), 1.19 (95% CI 0.72-1.96), and 0.90 (95% CI 0.47-1.74), respectively.
We did not find evidence to suggest that SCH is associated with increased MI risk among a population of predominantly older postmenopausal women with no prior history of MI.
亚临床甲状腺功能减退症（SCH）与心血管疾病风险增加有关。然而，很少有研究专门研究 SCH 与心肌梗死（MI）之间的关系，且其关系尚未得到充分理解。
本研究旨在评估绝经后妇女中 SCH 与心肌梗死（MI）发病风险之间的关系以及 SCH 的严重程度。
我们使用美国妇女健康倡议观察性研究中的基于人群的巢式病例对照设计，研究了 SCH 与绝经后妇女首次发生 MI 风险之间的关系。SCH 是使用基线时采集的血液样本进行评估的。研究将游离 T4 水平正常且促甲状腺激素水平大于 4.68-6.99 mU/L 或 7.00 mU/L 的患者定义为患有轻度 SCH 或中重度 SCH。MI 病例由经过培训的妇女健康倡议工作人员进行中心裁决。主要分析包括 736 例 MI 病例和 2927 名随机选择的亚组成员。多变量调整后的 Cox 比例风险模型用于评估 SCH 与 MI 风险之间的关系。
与甲状腺功能正常的参与者相比，任何 SCH 患者的多变量调整后的危险比（HR）为 1.05（95%置信区间[CI]：0.77-1.44）。轻度 SCH、中重度 SCH 和中重度 SCH 且存在抗甲状腺过氧化物酶抗体（TPOAb）的患者的 HR 分别为 0.99（95% CI：0.67-1.46）、1.19（95% CI：0.72-1.96）和 0.90（95% CI：0.47-1.74）。
在没有先前 MI 病史的大多数年龄较大的绝经后妇女人群中，我们没有发现 SCH 与 MI 风险增加相关的证据。
