Читать книгу Pathy's Principles and Practice of Geriatric Medicine - Группа авторов - Страница 58

The blood level of thyroxine remains unchanged as its production and clearance decrease. The triiodothyronine (T3) level decreases because of reduced transformation from thyroxine which results in increased reverse T3.

Table 2.2 Changes in hormone levels with age.

Source: Morley and McKee³³. © 2017 Elsevier.

Increased	Decreased
Adrenocorticotropic hormone	Growth hormone
Cortisol	Testosterone
Thyroid Stimulating Hormone	Oestrogen
Follicule stimulating hormone, luteinising hormone	Dehydroepiandrosterone sulfate
Arginine‐Vasopressin (daytime)	Arginine‐Vasopressin (nocturnal)
Norepinephrine	Aldosterone

The prevalence of thyroid nodules and thyroid neoplasm increases with age. Ageing is also associated with a tendency for hypothyroidism. Thus, annual TSH level measurement is suggested over the age of 60 even if the person is asymptomatic for hypothyroidism.

Previous studies suggest that there is a relationship between a mild increase in TSH level and longevity.^34‐35