Hypothyroidism - Treatment

Treatment

Various tests are used when deciding whether to treat a patient for hypothyroidism:

First, an elevated TSH (thyrotropin) level should be confirmed and thyroxine (T4) level determined.

Testing for antithyroid antibodies and determining cholesterol levels is also important.

Treating Hypothyroidism. Patients with full-blown hypothyroidism, indicated by clear symptoms and blood tests that show high TSH (generally 10 mU/L and above) and low thyroxine (T4) levels, must be treated with thyroid replacement.

Treating Subclinical Hypothyroidism. Considerable debate exists about whether to treat patients with subclinical hypothyroidism (slightly higher than normal TSH levels, normal thyroxine levels, and no obvious symptoms). Some doctors opt for treatment because of the following benefits, although evidence remains uncertain:

Preventing progression to full-blown hypothyroidism. Treating subclinical hypothyroidism will prevent progression to overt hypothyroidism. Only a minority of people with subclinical hypothyroidism go on to develop the active condition, however.

Preventing heart disease. Some studies have shown that treating subclinical hypothyroidism lowers cholesterol levels and may improve other heart functions, including blood pressure, endothelial function, and heart rate. However, current research from 2006 suggests that subclinical hypothyroidism poses little risk for heart disease and that untreated subclinical hypothyroidism will not increase heart disease risks.

Improving well-being. Some studies report that treating subclinical hypothyroidism may improve mild psychological symptoms, such as impaired mental functioning and depression. About 25% of patients with subclinical hypothyroidism report feeling better after taking thyroid medication even if they have not previously reported symptoms.

It is not clear, then, if the benefits of treating subclinical hypothyroidism outweigh the higher costs of testing and treatments. Experts against treatment argue that thyroid levels can vary widely, and subclinical hypothyroidism may not persist. In such cases, overtreatment leading to hyperthyroidism is a real risk.