Background: Thyroid function, insulin resistance, serum lipid, C-reactive protein (CRP) and homocysteine are associated with an increased cardiovascular risk in patients with autoimmune thyroiditis (AIT).
Objective: To evaluate the interrelations between thyroid function, insulin resistance, serum lipid concentrations, CRP and homocysteine in patients with AIT and subclinical hypothyroidism.
Subjects and methods: We recorded thyroid function tests, BMI and the levels of total cholesterol (TC), HDL, LDL-cholesterol, triglycerides (TG), apolipoprotein B (ApoB), ApoA1, lipoprotein (a) (Lp[a]), homocysteine, CRP, folic acid, vitamin B12, and insulin resistance markers comprising the HOMA-IR, HISI (Hepatic Insulin Sensitivity Index), WBISI (Whole-Body Insulin Sensitivity Index), IGI (Insulinogenic Index) in 500 patients with AIT, with a mean age of 47.2±14.8 years. A 75-g OGTT was performed in the morning, and blood samples were obtained every 30 min for 120 min for measurements of plasma glucose, insulin, and C-peptide. Statistical analysis was performed with ANOVA and Pearsons Correlations test. A two-tailed P value < 0.05 was considered significant.
Results: TSH levels were 3.680±11.877 UI/ml and BMI was 27.5±5.6 kg/m2. There were significant positive correlations between TSH and serum TC (r=0.167; P<0.001), LDL (r=0.131; P=0.004), TG (r=0.168; P<0.001), and ApoB (0.141; P=0.008). We found significant positive correlations between IGI and anti-TPO (r=0.179; P=0.005), CRP (r=0.162; P=0.02), and TSH (r=0.126; P=0.048). We also found significant positive correlations between HISI and TSH (r=0.173; P=0.006), and significant negative correlations between WBISI and CRP (r=−0.181; P=0.008).
Conclusions: In patients with AIT, there are positive associations between the levels of TSH, the lipid profile, and insulin resistance markers, such as IGI, and HISI.
Prague, Czech Republic
24 - 28 Apr 2010
European Society of Endocrinology