Abstract
Subclinical hypothyroidism can be diagnosed in 1% to 10% of the adult population, is more common in women, and increases with age. In many patients, treatment with L-thyroxine reduces low-density lipoprotein cholesterol, improves cardiac function, reduces symptoms of hypothyroidism, and diminishes neuropsychiatric symptoms. Treatment also reduces the likelihood of statin-induced myopathy. However, in double-blind, placebo-controlled trials of L-thyroxine therapy in subclinical hypothyroidism, cardiovascular and symptomatic benefits have been neither uniform nor definitive. In the absence of a large-scale, multicenter, randomized trial, physicians have to individualize therapy for each patient. Benefits of therapy are most likely to be realized in patients with thyroid-stimulating hormone levels greater than 10 mU/L on repeated measures, those with hypothyroid symptoms, those who are pregnant, those with a documented family history of hypothyroidism, and those with severe hyperlipidemia.
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Glueck, C.J., Streicher, P. Cardiovascular and medical ramifications of treatment of subclinical hypothyroidism. Curr Atheroscler Rep 5, 73–77 (2003). https://doi.org/10.1007/s11883-003-0071-5
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DOI: https://doi.org/10.1007/s11883-003-0071-5