The Research On Correlation Between Thyroid Disease And Serum Lipid Metabolism

Objective:Thyroid hormone (TH) is one kind of important endocrine hormones in the human body that can regulate the human body growth and has many influences to material and energy metabolism. The thyroid function exceptionally may cause dyslipidemia, the cardiovascular disease and the cerebrovascular disease. The former literatures have researched hypothyroidism or hyperthyroidism and Serum lipid metabolism relations, and the findings are inconsistent. This article explores the characteristic of lipid metabolism under different thyroid diseases and course, thus thyroid diseases and complications are further understanded.Methods:We collected 207 individuals with hyperthyroidism, hypothyroidism, subclinical hyperthyroidism, thyroiditis and euthyroidism. Thyroid hormone (free triiodothyronine, free thyroxine, Thyrotrophin) and serum lipid level (triglyceride, total cholesterol, high density lipoprotein, low density lipoprotein, apolipoprotein A, apolipoprotein B, lipoprotein (a)) were determined in all objects of the study. To analyze the difference in serum lipid and course of disese among each group, and identify determinants using correlation analysis.Results:1. TC, LDL, ApoB and Lpa are raised in the hypothyroidism group compared to the control group (P<0.05), while TC and LDL are reduced in the hyperthyroidism group (P<0.05). Lp(a) are raised in the subclinical hypothyroidism group compared to the control group (P<0.05). TC, TG, LDL and ApoB are raised in the hypothyroidism group compared to the subclinical hypothyroidism group (P<0.05).2. TSH have positive correlations with TC, LDL, ApoB, TG, HDL, ApoA and Lpa (r=0.748,0.686,0.616,0.386,0.338,0.327,0.207, P<0.01), FT3 have negative correlation correlations with TC, LDL, ApoB, TG, ApoA, HDL and Lpa (r=-0.765,-0.713,-0.656,-0.434,-0.318,-0.310,-0.208, P<0.01), FT4 have negative correlations with TC, LDL, ApoB, TG, ApoA, HDL and Lpa(r=-0.734,-0.675,-0.642,-0.424,-0.296,-0.285,-0.158, P<0.01).3. The course of hyperthyroidism is longer than thyroiditis (P<0.01)4. The courses of hyperthyroidism and thyroiditis have negative correlations with TC. ApoB and TG (r=-0.273,-0.263,-0.217, P<0.05).Conclusion: 1. TC and LDL are are closely related to thyroid function. TC and LDL are reduced in the hyperthyroidism group. TC and LDL are raised in the hypothyroidism group.2. ApoB and Lpa are closely related to hypothyroidism. ApoB and Lp(a) are raised in the hypothyroidism group. Lp(a) are raised in the subclinical hypothyroidism group. Hypothyroidism and subclinical hypothyroidism can cause cardiovascular and cerebrovascular diseases. And Hypothyroidism and subclinical hypothyroidism are important risk factors of atherosclerotic infarct of brain and myocardial infarction.3. TSH have positive correlations with Serum lipid spectrum. And TSH have significant positive correlations with TC,LDL,ApoB. FT3 and FT4 have negtive correlations with serum lipid spectrum. And FT3 and FT4 have significant negtive correlations with TC> LDL,ApoB. Thyroid function are closely related to serum lipid spectrum.4. TC, ApoB and TG are reduced along with progress of thyrotoxicosis.