Thyroid Guidelines

ABSTRACT & COMMENTARY

Source: Ladenson PW, et al. American Thyroid Association guidelines for detection of thyroid dysfunction. Arch Intern Med 2000;160(11):1573-1575.

There is a well known, albeit poorly understood, relationship between psychiatric disorders and thyroid dysfunction. The current article presents concuss guidelines from the American Thyroid Association regarding the detection of thyroid dysfunction. The guidelines were drafted by an eight-member committee, reviewed by the association’s 780 members, and modified as needed to develop consensus. In summary, the American Thyroid Association recommends that adults be screened for thyroid dysfunction by the measurement of serum thyrotropin concentration, beginning at age 35 years and every five years thereafter. Routine laboratory screening, typically via the measurement of serum thyrotropin concentration, is warranted because hypothyroidism and hyperthyroidism are treatable and clinical diagnosis of milder cases is not reliable. More frequent screening is indicated in the case of personal or family risk factors for thyroid disease. Screening is particularly important in women but is also justified and cost effective in men. The article reviews abnormalities in common laboratory tests that may suggest thyroid dysfunction.

Findings of these tests for hypothyroidism may include: hypercholesterolemia (1), hyponatremia (2), anemia (3), creatine phosphokinase and lactate dehydrogenase elevations (4), and hyperproglactinemia (5); and for hyperthyroidism: hypercalcemia (1), alkaline phosphatase elevation (2), and hepatocellular enzyme elevation (3). Any of these clinical and laboratory findings justify thyroid function testing, particularly if they are sustained for two weeks or more, occur in combination, have not been present previously during documented euthyroidism, or occur in individuals with increased risk of thyroid disease.

COMMENT BY LAUREN B. MARANGELL, MD

It has long been recognized that abnormalities in thyroid function can induce disturbances in mood. Similarly, mood disorders are often associated with alterations in peripheral thyroid hormones. The use of ultra sensitive immuno-radiometric assay to measure thyrotropin-stimulating hormone (TSH) has increased the reliability assessing the thyroid access. Indeed, peripheral TSH levels correlate inversely with cerebral activity as assessed with positron emission tomography in patients with mood disorders. New findings will continue to clarify the complex relationship between mood and thyroid hormone status. In the meantime, it is particularly important to assess thyroid status in patients with mood disorders who are not responding to standard treatments. In addition, it is reasonable to have a lower threshold for thyroid supplementation for individuals with mood disorders and residual symptoms such as fatigue.