Author: Herr Dr. Amoneit
Last saved by: Saritas, Sevim

The Association of Changes in Thyrotropin with Lipid profile and Metabolic syndrome in Healthy Adults
Ji-Eun Kim, M.D., Suwon,KR, Kang-Kun Lee, M.D. Seoul,KR,
Keun-Sang Yum, M.D., Seoul,KR. 
Department of Family Medicine, St. Vincent’s Hospital, The Catholic University of Korea.,
93 Jungbudaero, Paldalgu, Suwon, Korea

Background: Overt hypothyroidism is associated with metabolic syndrome by the effects of thyroid hormone on lipid and glucose metabolism. This relationship remains controversial in subclinical hypothyroidism; however, recent studies imply that increasing TSH level is positively associated with metabolic syndrome by changes in lipid profile.^,  Thus, to further examine the potential effects of increased TSH level, changes in TSH level were evaluated in association to lipid profile and other metabolic syndrome components. 

Cappola AR et al. Thyroid status, cardiovascular risk, and mortality in older adults. JAMA 2006;295:1033-41.

Rodondi N et al. Subclinical hypothyroidism and the risk of heart failure, other cardiovascular events, and death. Arch Intern Med 2005;165:2460-6.

Iqbal A et al. Serum lipid levels in relation to serum thyroid-stimulating hormone and the effect of thyroxine treatment on serum lipid levels in subjects with subclinical hypothyroidism: the Tromso Study. J Intern Med 2006;260:53-61.

Methods: A retrospective longitudinal study was performed on subjects who had undergone health examinations twice, with follow up interval of 2 years. Among 7127 subjects, 5544 (mean age 46.1 ± 10.4 years; 61% men) were included. Metabolic syndrome components were analyzed in accordance to TSH changes. 
Results: The prevalence of metabolic syndrome in this study was 19.7 %. TSH levels were positively associated with total cholesterol, HDL-C, LDL-C and negatively associated with fasting glucose. After average of 2 years of follow up, changes in waist circumference, systolic BP, diastolic BP, total cholesterol and triglyceride were positively associated in predicting changes in TSH levels. However, no significant association was seen between increase in TSH level and metabolic syndrome. 
Discussion: Lipid profiles of total cholesterol, LDL-C and HDL-C levels are significantly associated with increase in TSH levels, and the changes in such metabolic components may bring changes in TSH levels. However, the prevalence of metabolic syndrome is not directly related to changes in TSH levels.