Abstract
OBJECTIVE: Thyroid hormone influences lipoprotein metabolism. The role of menopausal status in this association has not been extensively studied. The aim of the present study is to evaluate the association between lipid parameters and mild elevations of thyrotropin (TSH), and whether menopause influences this relationship. STUDY DESIGN: A cross-sectional study was conducted with a sample of 2,914 women (aged 14-102 years) from the SardiNIA study. MAIN OUTCOME MEASURES: The association of TSH with blood lipid levels was examined using regression analyses, according to menopausal status. RESULTS: Postmenopausal women had lower serum TSH concentrations and higher levels of total cholesterol, low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), and triglycerides than did premenopausal women (p=0.001 or less for all). In premenopausal women, after adjusting for the confounders age, BMI, smoking, insulin and glycaemia, TSH showed a direct relation to the levels of total cholesterol (β=0.046, p=0.010), LDLc (β=0.044, p=0.016) and triglycerides (β=0.085, p<0.001), but no association with HDLc level. In the postmenopausal group, TSH was directly associated only with triglyceride levels (β=0.103, p=0.014). CONCLUSIONS: The association between mild elevation of TSH and lipid levels is influenced by menopausal status. Further research is needed to clarify this finding.