Thyroid diseases are the commonest endocrine disorders in the general population. In most of the cases, they are consistent with benign conditions which may be asymptomatic or affect people at a variable extent. Since they often represent
chronic conditions their prevalence increases by age and reaches in elderly the highest rates.
Thyroid nodules are a common clinical finding. Most subjects with
thyroid nodules have few or no symptoms.
Thyroid nodules are more commonly non-functioning. However, in elderly, toxic multinodular
goiter is the most frequent cause of spontaneous
hyperthyroidism and often, it emerges insidiously from nontoxic multinodular
goiter. Although
autoimmune thyroiditis is the most common cause of
hypothyroidism in elderly subjects, other causes, such as drugs, neck
radiotherapy,
thyroidectomy or radioiodine
therapy, are frequently observed among these subjects. A small subset of medications including
dopamine agonists,
glucocorticoids and
somatostatin analogs affect thyroid function through suppression of TSH. Other medications that may affect TSH levels are
metformin,
antiepileptic medications,
lithium carbonate and
iodine-containing medications. Other drugs can alter T4 absorption, T4 and T3 transport in serum and metabolism of T4 and T3, such as
proton-pump inhibitors and
antacids,
estrogens,
mitotane and
fluorouracil,
phenobarbital and
rifampin.
Amiodarone administration is associated with
thyrotoxicosis or
hypothyroidism.
Thyroid cancer has similar characteristics in elderly as in general population, however the rate of aggressive forms such as the anaplastic histotype, is higher in older than younger subjects. Diagnosis of
thyroid diseases includes a comprehensive medical history and physical examination and appropriate laboratory tests. A correct diagnosis of
thyroid diseases in the elderly is crucial for proper treatment, which consists in the removal of medications that may alter thyroid function, in the use of levo-
thyroxine in case of
hypothyroidism, anti-thyroid drugs in case of
hyperthyroidism and use of surgery, radioiodine
therapy and percutaneous ablative procedures in selected cases. In conclusion,
thyroid diseases in patients older than 60 years deserve attention from different points of view: the prevalence is different from the young adult; symptoms are more nuanced and makes difficult the diagnosis; age and comorbidity often force therapeutic choices and may limit safety and efficacy of
therapy. Finally, in elderly patients for whom specific
therapy is necessary, more gradual and careful therapeutic approach and close follow-up are recommended in order to minimize the alterations of thyroid function which are induced by many drugs commonly used in clinical practice.