Which statement about hypothyroidism is false?

The statement that the rate of hypothyroidism decreases with age is false. In fact, the prevalence of hypothyroidism tends to increase with age, particularly in older adults. Various factors contribute to this trend, including an increase in autoimmune disorders, such as Hashimoto thyroiditis, which is known to cause hypothyroidism, and a general decline in thyroid function that can occur as people age.

In contrast, the other statements are accurate. Iodine deficiency is the leading cause of hypothyroidism globally, particularly in regions where iodine intake is insufficient. Hashimoto thyroiditis is indeed the most common form of autoimmune hypothyroidism; it is characterized by the immune system attacking the thyroid gland, leading to decreased hormone production. Additionally, certain medications, including lithium, are recognized as risk factors for developing hypothyroidism due to their effects on thyroid metabolism and hormone synthesis.