Definition, Causes, Pathophysiology, and Management of Hypothyroidism

Abstract

The thyroid gland produces insufficient amounts of thyroid hormone, which is known as hypothyroidism. It can be primary (caused by an abnormality in the thyroid gland itself) or secondary/central. Between 3.8% and 4.6% of the general population has hypothyroidism. Hypothyroidism can also develop secondary to hypothalamic and pituitary disorders. These endocrine conditions occur primarily in patients who have undergone intracranial irradiation or surgical removal of a pituitary adenoma. Diagnosis of hypothyroidism is not easy because most of the symptoms, especially in mild cases, are nonspecific and are frequently attributed to other causes or to the aging process itself. Levothyroxine dosage selection, patient-appropriate serum thyrotropin (thyroid stimulating hormone) goal selection, and maintenance of that goal are the fundamental components of treating hypothyroidism. Although liothyronine (synthetic T3) has uniform potency, it is more expensive, harder to monitor with standard laboratory testing, and has a higher rate of severe cardiac effects.