Low serum free XXXX concentrations associate with increased arterial stiffness in euthyroid subjects: a population-based cross-sectional study.

@entity1 @entity455 @entity1294 @entity8789 @entity1955 @entity65 @entity413 @entity1954
UNASSIGNED: Some studies suggest that even in euthyroid subjects, thyroid function may affect @entity1294 factors. We aimed to determine whether @entity8789 or thyroid autoantibodies are associated with arterial stiffness in middle-aged and elderly Chinese subjects with euthyroidism. A cross-sectional, population-based study was conducted in Nanjing, China. A total of 812 euthyroid subjects (mean age [56.75      8.34] years; 402 @entity1 ) without @entity455 and major @entity1294 factors were included. Clinical factors, oral @entity413 tolerance test results, homeostasis model assessment for insulin resistance (HOMA-IR) results, and serum levels of lipids, free @entity1954 (FT3), free @entity1955 (FT4), thyroid-stimulating hormone (TSH), and thyroid autoantibodies were measured. Arterial stiffness was assessed using brachial-ankle pulse wave velocity (baPWV). In Pearson correlation analyses, baPWV correlated inversely with FT4 (r  =  -0.146, P  <  0.001), but not with FT3 (r  =  0.008, P  =  0.816) or TSH (r  =  0.055, P  =  0.118). Subsequently, a multiple stepwise regression analysis revealed a significant and independent association of FT4 with baPWV in euthyroid subjects (b  =  -0.076, P  =  0.005). After adjusting for potential cardiovascular risk factors, mean diastolic blood pressure (DBP), HOMA-IR, and baPWV levels decreased across increasing FT4 quartiles (DBP, P  <  0.001; HOMA-IR, P  <  0.001; baPWV, P  =  0.003). No difference in baPWV was observed between the positive and the negative thyroid antibody groups (15.23      3.30  m/s vs. 15.73      3.05  m/s, P  >  0.05). FT4 levels were inversely associated with arterial stiffness in euthyroid subjects. A prospective study is warranted to validate whether subjects with low-normal FT4 levels have a high incidence of @entity65 .
