Chapter 106 - Hypothyroidism in the Middle Aged and Elderly: Clinical Aspects

Abstract

Thyroid hypofunction is common in adults in middle age and in the elderly, especially among women. Autoimmune thyroiditis is the most frequent etiology of hypothyroidism in iodine-sufficient areas. Postoperative hypothyroidism, treatment of hyperthyroidism, thyrotropin deficiency, iodine excess, use of certain drugs, and subacute and painless thyroiditis are also recognizable causes of thyroid hypofunction. Symptoms of hypothyroidism are highly variable, depending on age, time of evolution and degree of thyroid failure. Clinical diagnosis of hypothyroidism may be difficult because of the lack of typical symptoms, or because the lack of specificity of symptoms in the elderly. Usually elevated serum TSH levels and low T4 levels are enough to diagnose primary hypothyroidism in aged people, however, thyroid function tests may be affected by the ageing process, nonthyroidal illnesses and drugs. Low T4 levels with normal-low TSH levels are characteristically found in patients with central hypothyroidism. In most patients, clinical history and physical examination and a limited number of investigations are enough to diagnose the cause of thyroid hypofunction. Because of the clinical peculiarities of hypothyroidism in the elderly, this hormonal deficiency should be taken into account by all clinicians taking care of elderly people.