How Selective Are the New Guidelines for Treatment of Subclinical Hypothyroidism for Patients with Thyrotropin Levels At or Below 10 mIU/L?

Abstract

By consensus, a thyrotropin (TSH) level persistently >10 mIU/L is an indication for the treatment of subclinical hypothyroidism (SCH). Controversy exists regarding patients whose TSH level is elevated but <10 mIU/L. Recently, the American Thyroid Association (ATA) and the American Association of Clinical Endocrinologists (AACE) published their position about factors that should be considered in the decision on treating SCH. This study evaluated the frequency of these factors among adult (non-pregnant) women with SCH whose TSH levels are ≤10 mIU/L. The presence of the conditions that should be considered for the treatment of SCH according to ATA and AACE was evaluated in 252 women who were diagnosed with SCH and had TSH levels ≤10 mIU/L. Pregnant women were excluded. Antithyroperoxidase antibodies (TPOAbs) were detected in 137 (54.3%) women. A high cardiovascular risk was observed in 43 (17%) women. Eighty (31.7%) women who were not at high cardiovascular risk presented at least one classical risk factor (arterial hypertension, elevated level of low-density lipoprotein-cholesterol or low level of high-density lipoprotein-cholesterol, smoking, or first-degree family history of premature coronary artery disease). At least one symptom or sign of hypothyroidism that could not be explained by another condition was observed in 180 (71.4%) women. Two hundred thirty-two (92%) women had positive TPOAbs, or at least one classical cardiovascular risk factor, or at least one symptom or sign of hypothyroidism. According to the new ATA and AACE guidelines, L-T4 therapy would be considered for 92% of women with SCH and TSH ≤10 mIU/L.