Section of Endocrinology, Diabetes, and Metabolism, University of Chicago, Chicago, Illinois, USA.
Curr Opin Endocrinol Diabetes Obes. 2023 Oct 1;30(5):218-224. doi: 10.1097/MED.0000000000000818. Epub 2023 Jun 8.
Subclinical thyroid disease is defined by a thyroid stimulating hormone (TSH) level outside of the normal range with normal circulating thyroid hormone levels. Excess adverse cardiovascular outcomes have been observed in certain patient populations with subclinical hypothyroidism (SCH) and hyperthyroidism (SCHr). The role of thyroid hormone and antithyroid treatments for subclinical thyroid disease remains debated.
Cardiovascular disease appears to be a major mediator of all-cause mortality in patients with SCH, in particular those aged at least 60 years of age. In contrast, pooled clinical trial results did not find that levothyroxine reduced the incidence of cardiovascular events or mortality in this patient population. The association between SCHr and atrial fibrillation is well established; however, a 5-year follow-up of older patients with mild (TSH 0.1-0.4 mIU/l) SCHr found no increased incidence of atrial fibrillation. Separately, SCHr was associated with derangements in endothelial progenitor cell function that may underlie vascular disease independent from effects on cardiac function.
The impact of treatment of subclinical thyroid disease on cardiovascular outcomes remains uncertain. Additional prospective and trial data are needed to evaluate treatment effects on cardiovascular outcomes in younger populations.
亚临床甲状腺疾病的定义是促甲状腺激素（TSH）水平超出正常范围，而循环甲状腺激素水平正常。在某些亚临床甲状腺功能减退症（SCH）和甲状腺功能亢进症（SCHr）患者群体中观察到了过多的不良心血管结局。甲状腺激素和抗甲状腺治疗在亚临床甲状腺疾病中的作用仍存在争议。
心血管疾病似乎是 SCH 患者全因死亡率的主要介导因素，尤其是年龄至少 60 岁的患者。相比之下，汇总的临床试验结果并未发现左甲状腺素可降低该患者人群的心血管事件发生率或死亡率。SCHr 与心房颤动之间的关联已得到充分证实；然而，对轻度（TSH 0.1-0.4 mIU/l）SCHr 的老年患者进行的 5 年随访并未发现心房颤动发生率增加。此外，SCHr 与内皮祖细胞功能障碍有关，这可能与心脏功能无关的血管疾病有关。
治疗亚临床甲状腺疾病对心血管结局的影响仍不确定。需要额外的前瞻性和试验数据来评估治疗对年轻人群心血管结局的影响。
