Semin Thromb Hemost 2011; 37(1): 027-034
DOI: 10.1055/s-0030-1270068
© Thieme Medical Publishers

New Insights into Subclinical Hypothyroidism and Cardiovascular Risk

Leonidas H. Duntas1 , Bernadette Biondi2
  • 1Endocrine Unit, Evgenidion Hospital, University of Athens, Medical School, Athens, Greece
  • 2Department of Clinical and Molecular Endocrinology and Oncology, School of Medicine, University of Naples Federico II, Naples, Italy
Further Information

Publication History

Publication Date:
19 January 2011 (online)

ABSTRACT

Subclinical hypothyroidism (SH) is a frequent condition affecting millions of people around the world. Defined by increased thyrotropin-stimulating hormone (TSH) and accompanied by normal thyroid hormone levels, SH reflects a mild tissue hypothyroidism that has been associated with metabolic derangements and—although this issue is still contentious—possibly with increased cardiovascular risk. Depending on the degree of TSH elevation, SH has accordingly been associated with hyperlipidemia, arterial hypertension, and cardiovascular disease (CVD), as well as, increasingly, newly emerging CVD risk factors such as serum C-reactive protein and retinol binding protein 4 levels. There have also been reports of abnormalities in glucose metabolism and of hemostatic parameters, mainly underscored by the increased activity of factor VII. This review discusses the results of the latest studies on the various parameters affected by SH while highlighting the need for timely treatment with levothyroxine.

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Leonidas H DuntasM.D. 

Professor of Endocrinology, Endocrine Unit, Evgenidion Hospital, University of Athens

20 Papadiamantopoulou Street, 115 28 Athens, Greece

Email: ledunt@otenet.gr