Parle J V, Maisonneuve P, Sheppard M C, Boyle P, Franklyn J A
Division of Primary Care, Public and Occupational Health, Birmingham, UK.
Lancet. 2001 Sep 15;358(9285):861-5. doi: 10.1016/S0140-6736(01)06067-6.
Low serum thyrotropin, in combination with normal concentrations of circulating thyroid hormones, is common, especially in elderly people and in individuals with a history of thyroid disease. We aimed to assess the long-term effects of subclinical hyperthyroidism on mortality.
We did a population-based study of mortality in a cohort of 1191 individuals not on thyroxine or antithyroid medication. All participants were aged 60 years or older. We measured concentration of thyrotropin in serum at baseline in 1988-89. We recorded vital status on June 1, 1999, and ascertained causes of death for those who had died. We compared data for causes of death with age-specific, sex-specific, and year-specific data for England and Wales. We also compared mortality within the cohort according to initial thyrotropin measurement.
During 9733 person-years of follow-up, 509 of 1191 people died, the expected number of deaths being 496 (standardised mortality ratio [SMR] 1.0, 95% CI 0.9-1.1). Mortality from all causes was significantly increased at 2 (SMR 2.1), 3 (2.1), 4 (1.7), and 5 (1.8) years after first measurement in those with low serum thyrotropin (n471). These increases were largely accounted for by significant increases in mortality due to circulatory diseases (SMR 2.1, 2.2, 1.9, 2.0, at years 2, 3, 4, and 5 respectively). Increases in mortality from all causes in years 2-5 were higher in patients with low serum thyrotropin than in the rest of the cohort (hazard ratios for years 2, 3, 4, and 5 were 2.1, 2.2, 1.8, and 1.8, respectively). This result reflects an increase in mortality from circulatory diseases (hazard ratios at years 2, 3, 4, and 5 were 2.3, 2.6, 2.3, 2.3), and specifically from cardiovascular diseases (hazard ratios at years 2, 3, 4, and 5 were 3.3, 3.0, 2.3, 2.2).
A single measurement of low serum thyrotropin in individuals aged 60 years or older is associated with increased mortality from all causes, and in particular mortality due to circulatory and cardiovascular diseases.
血清促甲状腺激素水平低，同时循环甲状腺激素浓度正常的情况很常见，尤其是在老年人和有甲状腺疾病史的个体中。我们旨在评估亚临床甲状腺功能亢进对死亡率的长期影响。
我们对1191名未服用甲状腺素或抗甲状腺药物的人群进行了一项基于人群的死亡率研究。所有参与者年龄均在60岁及以上。我们在1988 - 1989年基线时测量了血清促甲状腺激素浓度。我们记录了1999年6月1日的生命状态，并确定了死亡者的死因。我们将死因数据与英格兰和威尔士的年龄、性别及年份特异性数据进行了比较。我们还根据最初的促甲状腺激素测量结果比较了队列中的死亡率。
在9733人年的随访期间，1191人中509人死亡，预期死亡人数为496人（标准化死亡率[SMR]为1.0，95%可信区间为0.9 - 1.1）。血清促甲状腺激素水平低的人群（n = 471）在首次测量后2年（SMR为2.1）、3年（2.1）、4年（1.7）和5年（1.8）时，全因死亡率显著增加。这些增加主要是由于循环系统疾病导致的死亡率显著上升（分别在第2、3、4和5年时SMR为2.1、2.2、1.9、2.0）。血清促甲状腺激素水平低的患者在第2 - 5年的全因死亡率增加高于队列中的其他人群（第2、3、4和5年的风险比分别为2.1、2.2、1.8和1.8）。这一结果反映了循环系统疾病死亡率的增加（第2、3、4和5年的风险比分别为2.3、2.6、2.3、2.3），特别是心血管疾病死亡率的增加（第2、3、4和5年的风险比分别为3.3、3.0、2.3、2.2）。
对60岁及以上个体单次测量血清促甲状腺激素水平低与全因死亡率增加相关，尤其是循环系统和心血管疾病导致的死亡率增加。
