Disclosing subclinical thyroid disease. An approach to mild laboratory abnormalities and vague or absent symptoms.

Patients with subclinical thyroid disease often have no apparent symptoms or only nonspecific complaints. However, increasing evidence that early disease is associated with behavioral, psychiatric, biochemical, and organ-specific abnormalities has led several specialty organizations to publish or modify position papers. Serum TSH testing is the most sensitive method of identifying early thyroid dysfunction. It should be considered in patients who have risk factors for mild thyroid failure, have symptoms that could be related to thyroid disease, or are taking exogenous thyroid hormone. T4 therapy should be strongly considered in patients with a TSH level of 10 mIU/L or more. If observation is elected in asymptomatic patients with lesser TSH elevation, periodic measurements are advised. In patients with TSH suppression who are taking thyroid hormone, the dose should be lowered. If the TSH level is decreased because of endogenous suppression and free-T4 and T3 levels are normal, options include observation and treatment with an antithyroid drug or thyroid ablation. Early therapy should be considered in older patients and those with heart disease or nodular thyroid disease. The goal of all treatment methods should be to keep the TSH level in the normal range.