甲狀腺功能和突發性心因猝死

最近一位副甲狀腺亢進洗腎患者去把副甲狀腺開掉了，但因為她也有thyroid goiter影響到呼吸道，所以順便也做了total thyroidectomy，所以外科醫師開了thyroxine給患者吃。然而，到底thyroxine要用到那一種劑量？怎麼看TSH/FT4 報告？以下這研究可以給大家一個意見參考。

結論：即使在euthyroid狀態下(依TSH在正常範圍內)，有較高的FT4患者，突發性心因猝死的機會較高。

註：這讓我想起，以前在新陳代謝科學習時，前輩都說，thyroxine補最低有較劑量即可。

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Thyroid Function and Sudden Cardiac Death

A Prospective Population-Based Cohort Study

Circulation

http://dx.doi.org/10.1161/CIRCULATIONAHA.115.020789

Published: September 6, 2016

BACKGROUND: The association between thyroid function and cardiovascular disease is well established, but no study to date has assessed whether it is a risk factor for sudden cardiac death (SCD). Therefore, we studied the association of thyroid function with SCD in a prospective population-based cohort.

METHODS: Participants from the Rotterdam Study ≥45 years with thyroid-stimulating hormone or free thyroxine (FT4) measurements and clinical follow-up were eligible. We assessed the association of thyroid-stimulating hormone and FT4 with the risk of SCD by using an age- and sex-adjusted Cox proportional-hazards model, in all participants and also after restricting the analysis to euthyroid participants (defined by thyroid-stimulating hormone 0.4–4.0 mIU/L). Additional adjustment included cardiovascular risk factors, notably hypertension, serum cholesterol, and smoking. We stratified by age and sex and performed sensitivity analyses by excluding participants with abnormal FT4 values (reference range of 0.85–1.95 ng/dL) and including only witnessed SCDs as outcome. Absolute risks were calculated in a competing risk model by taking death by other causes into account.

RESULTS: We included 10 318 participants with 261 incident SCDs (median follow-up, 9.1 years). Higher levels of FT4 were associated with an increased SCD risk, even in the normal range of thyroid function (hazard ratio, 2.28 per 1 ng/dL FT4; 95% confidence interval, 1.31–3.97). Stratification by age or sex and sensitivity analyses did not change the risk estimates substantially. The absolute 10-year risk of SCD increased in euthyroid participants from 1% to 4% with increasing FT4 levels.

Conclusions: Higher FT4 levels are associated with an increased risk of SCD, even in euthyroid participants.