Age-related variation in thyroid function – a narrative review highlighting important implications for research and clinical practice

Thyroid Research

Review

Justyna Witczak¹  Rahim Khan¹  Andrew Lansdown¹  Colin M. Dayan²  Peter N. Taylor³  Aled Rees⁴  Onyebuchi Okosieme⁵ 

[1] Department of Endocrinology, University Hospital of Wales, Cardiff, UK;Thyroid Research Group Institute of Molecular and Experimental Medicine, C2 link corridor, UHW, Cardiff University School of Medicine, Heath Park, Cardiff, UK;Thyroid Research Group Institute of Molecular and Experimental Medicine, C2 link corridor, UHW, Cardiff University School of Medicine, Heath Park, Cardiff, UK;Department of Endocrinology, University Hospital of Wales, Cardiff, UK;Thyroid Research Group Institute of Molecular and Experimental Medicine, C2 link corridor, UHW, Cardiff University School of Medicine, Heath Park, Cardiff, UK;Department of Endocrinology, University Hospital of Wales, Cardiff, UK;Neuroscience and Mental Health Research Institute, Cardiff University School of Medicine, Cardiff, UK;Thyroid Research Group Institute of Molecular and Experimental Medicine, C2 link corridor, UHW, Cardiff University School of Medicine, Heath Park, Cardiff, UK;Diabetes Department, Prince Charles Hospital, Cwm Taf Morgannwg University Health Board, Merthyr Tydfil, UK;

关键词: Thyroid function;    TSH;    FT4;    Reference interval;    Children;    Adolescents;    Aging;    Elderly;    T4;    T3;    Tri-iodothyronine;    Thyroxine;   

DOI  :  10.1186/s13044-023-00149-5

 received in 2022-12-27, accepted in 2023-02-05,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundThyroid hormones are key determinants of health and well-being. Normal thyroid function is defined according to the standard 95% confidence interval of the disease-free population. Such standard laboratory reference intervals are widely applied in research and clinical practice, irrespective of age. However, thyroid hormones vary with age and current reference intervals may not be appropriate across all age groups. In this review, we summarize the recent literature on age-related variation in thyroid function and discuss important implications of such variation for research and clinical practice.Main textThere is now substantial evidence that normal thyroid status changes with age throughout the course of life. Thyroid stimulating hormone (TSH) concentrations are higher at the extremes of life and show a U-shaped longitudinal trend in iodine sufficient Caucasian populations. Free triiodothyronine (FT3) levels fall with age and appear to play a role in pubertal development, during which it shows a strong relationship with fat mass. Furthermore, the aging process exerts differential effects on the health consequences of thyroid hormone variations. Older individuals with declining thyroid function appear to have survival advantages compared to individuals with normal or high-normal thyroid function. In contrast younger or middle-aged individuals with low-normal thyroid function suffer an increased risk of adverse cardiovascular and metabolic outcomes while those with high-normal function have adverse bone outcomes including osteoporosis and fractures.ConclusionThyroid hormone reference intervals have differential effects across age groups. Current reference ranges could potentially lead to inappropriate treatment in older individuals but on the other hand could result in missed opportunities for risk factor modification in the younger and middle-aged groups. Further studies are now needed to determine the validity of age-appropriate reference intervals and to understand the impact of thyroid hormone variations in younger individuals.

【 授权许可】

CC BY   
© The Author(s) 2023. corrected publication 2023

【 图 表 】

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