亚临床甲状腺功能减退症

亚临床甲状腺功能减退症(甲减)是一种业临床甲状腺疾病.诊断标准是血清促甲状腺激素(TSH)水平高于正常上限而游离T4水平尚在正常范围.目前全世界业临床甲减的平均患病率为4%～10%,主要发生在女性和老年人群.桥本甲状腺炎是最常见的病因.其卡要的临床危害包括引起血脂异常、导致动脉粥样硬化和,冠心病、影响认知功能,还可导致不孕和流产.治疗主要针对血清TSH10 mIU/L的患者,应用左旋-T4替代治疗.对于血清TSH 4～10 mIU/L,特别是甲状腺自身抗体阳性者需密切监测.此外,对妊娠期亚临床甲减患者的治疗要求控制TSH<2.5 mlU/L.

Subclinical hypothyroidism

Subclinical hypothyroidism is one of subclinical thyroid diseases, which is defined as a serum thyroid stimulating hormone(TSH) concentration above the statistically defined upper limit of the ref-erence range when serum free T4 concentration is within its reference range. The average worldwide preva-lence has been reported to be in the range of 4%-10% ,mainly among women and the elderly. The most com-monly cause of subclinical hypothyroidism is Hashimoto's thyroiditis. Subclinical hypothyroidism is associated with disorders of serum lipid, development of atherosclerosis and cardiovascular disease, presence of cognitive impairment,infertility and miscarriage. L-thyroxine substitutive therapy is recommended when TSH is above 10 mIU/L. Patients with serum TSH between 4 and 10 mIU/L should be monitored frequently especially if thyroperoxidase antibody is positive. The goal of the therapy for the pregnant women with subclinical hypothy-roidism is serum TSH less than 2.5 mIU/L.