Subclinical Hypothyroidism: an Update for Primary Care Physicians

Overview

Journal Mayo Clin Proc

Specialty General Medicine

Date 2009 Jan 6

PMID 19121255

Citations 91

Authors

Vahab Fatourechi

Affiliations

Soon will be listed here.

Abstract

Subclinical hypothyroidism (SCH), also called mild thyroid failure, is diagnosed when peripheral thyroid hormone levels are within normal reference laboratory range but serum thyroid-stimulating hormone (TSH) levels are mildly elevated. This condition occurs in 3% to 8% of the general population. It is more common in women than men, and its prevalence increases with age. Of patients with SCH, 80% have a serum TSH of less than 10 mIU/L. The most important implication of SCH is high likelihood of progression to clinical hypothyroidism. The possibility that it is a cardiovascular risk factor has been a subject of debate. Large-scale randomized studies are needed for evidence-based recommendations regarding screening for mild thyroid failure and levothyroxine therapy for this condition. Currently, the practical approach is routine levothyroxine therapy for persons with a persistent serum TSH of more than 10.0 mIU/L and individualized therapy for those with a TSH of less than 10.0 mIU/L.

Citing Articles

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Characteristics of blood lipid and metabolic indicators in subclinical hypothyroidism patients: a retrospective study.

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