LAUSR

The existence of a physiological link between the heart and the thyroid is known since the end of XVIII century when Dr. Caleb Parry described the association between a swollen thyroid gland and an enlarged heart in a patient lamenting palpitations [1]. In the following years, the fundamental work of Graves, von Basedow, and Zondek has certified the basic knowledge of modern physiology that places thyroid hormones at the fine tuning of cardiac function. Two hundred andmore years later, the field is still open for investigation, and recent papers have reignited the passionate quest of the cardiovascular effects of the thyroid hormones, this time with a particular emphasis on the cardiovascular outcomes. In this issue of the International Journal of Cardiology, Golledge et al. report that older euthyroid patients with normal-high levels of serum FT4 are at higher risk of new major cardiovascular events, especially myocardial infarction [2]. This observation builds momentum to reconsider the role of thyroid function in the elderly. Indeed, the assessment of FT4 levels in older patients might help to predict both the all-cause mortality and the incidence of new cardiovascular events and stratify this population in groups with different outcomes. Furthermore, the confirmation of a causal relationship between FT4 levels in the upper quartile and risk of overall mortality or incidence of new cardiovascular events could lead to a redefinition of the reference ranges for FT4 in the elderly [3] and to the identification of a new pathological entity, specific of aging, in which the coexistence of normal thyrotropin levels and higher FT4 levels within the normality range is associated with poorer outcomes. The issue of age has been previously investigated. The consensus is on the reciprocal relationship between all-cause mortality and serum levels of FT4 in euthyroid patients. In particular, the negative effect of normal-high FT4 levels on old patients' outcome might be cumulative