Background
: There are several reports on the association between hypothyroidism and coronary heart disease. But, it is not convincing whether the subclinical hypothyroidism is associated with the coronary heart disease or not. We have attempted to investigate the association between subclinical hypothyroidism and several coronary risk factors, and the difference of Framingham risk score between subclinical hypothyroidism and normal control subjects in women above 55 years old, who have higher prevalence in subclinical hypothyroidism.

Methods : This study involved th subjects above age 55, who visited the health promotion center in a university hospital from 1995 to 2000. Subclinical hypothyroidism was defined as a TSH level greater than 4.1 uIU/mL in the presence of a normal T3 (87-184 ng/dL) and T4 (5.6-13.1ug/dL) level. We measured thyroid function test(TSH, T3, T4) and the coronary risk factors (systolic and diastolic blood pressure, total cholesterol, LDL cholesterol, HDL cholesterol, triglyceride, fasting glucose, uric acid, C-reactive protein, and body mass index). Also, we calculated the Framingham risk score from their sum.

Results : There were no significant differences between the subclinical hypothyroidism patients and normal control subjects with coronary risk assessment in women above 55-years-old.