title: [Is subclinical hypothyroidism a cardiovascular risk factor?].
abstract: OBJECTIVE
  Subclinical hypothyroidism defined by the presence of elevated TSH levels but normal free T4 level is a common situation. Its consequences on health are yet on debate and the interest of a precocious treatment remains surrounded by controversy.
  
  
  CONCLUSIONS
  The relationship between subclinical hypothyroidism and cardiovascular disease has been evaluated by several cross-sectional and longitudinal studies. Subclinical hypothyroidism has direct but subtle effects on the heart function, on the peripheral vascular resistance, and is associated with a mild elevation of LDL-cholesterol levels; all abnormalities may be partly reversed by a thyroxine supplementation. Data of the literature give insufficient evidence as to whether subclinical hypothyroidism is an independent cardiovascular risk factor. However treatment of subjects with TSH levels up or near to 10 mU/l would probably be beneficial in the prevention of cardiovascular disease.
  
  
  CONCLUSIONS
  Based on observational and interventional studies there are some arguments on the benefit of euthyroidism restoration only in patients with TSH levels superior to 10 mU/l.
authors.affiliation: Service de médecine interne, CHU de Hautepierre, 67098 Strasbourg cedex, France. jean-louis.schlienger@chru-strasbourg.fr
authors.forename: J-L
authors.initials: JL
authors.lastname: Schlienger
authors.forename: S
authors.initials: S
authors.lastname: Vinzio
authors.forename: F
authors.initials: F
authors.lastname: Grunenberger
authors.forename: F
authors.initials: F
authors.lastname: Luca
authors.forename: B
authors.initials: B
authors.lastname: Goichot
mesh_terms: D002318:Cardiovascular Diseases / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D008078:Cholesterol, LDL / Q000097:blood; D003430:Cross-Sectional Studies; D005602:France / Q000453:epidemiology; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D015994:Incidence; D008137:Longitudinal Studies; D015995:Prevalence; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood
chemical_list: D008078:Cholesterol, LDL; D013972:Thyrotropin; D013974:Thyroxine