The announcement that new clinical practice guidelines for the diagnosis and treatment of hypothyroidism are published in the current issue of Thyroid was made by The American Thyroid Association (ATA). The Guidelines were developed jointly by the ATA and the American Association of Clinical Endocrinologists (AACE) and will be presented on Sunday, Sept. 23, during the 82nd Annual Meeting of the American Thyroid Association in QuĂ©bec City, QuĂ©bec, Canada.
Hypothyroidism is caused by an underactive thyroid gland that cannot produce enough thyroid hormone. Symptoms of hypothyroidism are often mild and commonly include dry skin, cold sensitivity, fatigue, sluggishness, muscle cramps, voice changes, and constipation. Environmental iodine deficiency is the most common cause of hypothyroidism on a worldwide basis. However, in areas of iodine sufficiency, such as the United States, the most common cause of hypothyroidism is chronic autoimmune thyroiditis (Hashimoto''s thyroiditis).
The Guidelines present 52 evidence-based recommendations developed by a join ATA and AACE task force of experts in thyroidology, led by Jeffrey R. Garber, MD, , president of the American College of Endocrinology (ACE) and Harvard Vanguard Medical Associates'' endocrine division chief. The Guidelines were developed following a rigorous review of relevant medical literature and the current standards of care, and drew upon the task force''s collective knowledge and experience in diagnosing and caring for patients with hypothyroidism. (The task force defined overt hypothyroidism as a Thyroid Stimulating Hormone (TSH) level above 10 mIU/L, and subclinical hypothyroidism as a TSH less than 10 mIU/L, with lower Free Thyroxine (Free T4) levels.)
"The Clinical Practice Guideline for Management of Hypothyroidism'' is based on a comprehensive review and assessment by experts of what has been published about hypothyroidism," said Dr. Garber. "We trust that by providing evidenced-based guidelines for patients with hypothyroidism the quality of care for this common, important and readily treatable condition will improve."
Key recommendations include:
- An endocrinologist should be consulted when children and infants, pregnant patients and women planning conception, those with heart disease, and those with other endocrine diseases such as adrenal and pituitary disorders, are affected.
- Serum TSH is the single best screening test for hypothyroidism. It is not sufficient for assessing hospitalized patients or when central hypothyroidism is present or suspected (central hypothyroidism is due to a decrease in the secretion of TSH from the pituitary gland).
- Hypothyroidism should be treated with Levothyroxine (T4).
- No clinical data exists to support the effectiveness of over-the-counter products marketed for "thyroid support" or to promote "thyroid health."
- Levothyroxine (T4) and Levotriiodothyronine (T3) combinations, including desiccated thyroid, should not be used during pregnancy or in those who are planning pregnancy.
- Mild TSH elevations in the elderly may be a normal manifestation of aging and not necessarily indicate hypothyroidism.