title: Association between the serum concentration of triiodothyronine with components of metabolic syndrome, cardiovascular risk, and diet in euthyroid post-menopausal women without and with metabolic syndrome.
abstract: OBJECTIVE
  To determine the association between the serum concentration of triiodothyronine (T3) with components of metabolic syndrome (MetS), cardiovascular risk (CVR), and diet in euthyroid post-menopausal women without and with MetS.
  
  
  METHODS
  A cross-sectional study was performed in 120 voluntary women of an indigenous population from Tlaxcala-México. Euthyroid status was assessed measuring the serum concentration of thyrotropin (TSH) and thyroid hormones, while that of estradiol was measured to confirm the postmenopausal condition. MetS was diagnosed using the American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement (AHA/NHLBI) criterion. Estimation of CVR was calculated based on the Framingham scale. Diet components were evaluated based on survey applications. Correlations, logistic regression analyses, ANOVA or Kruskall-Wallis, and chi-square tests were used to determine significant differences (P ≤ 0.05) between women without MetS and women with MetS having different serum concentrations of T3.
  
  
  RESULTS
  Triiodothyronine was positively correlated with insulin but negatively correlated with glucose, high-density lipoprotein cholesterol (HDL-C), and CVR. Compared to women without MetS, women with MetS and low-normal T3 concentration showed a high risk for hyperglycemia and moderate/high risk for CVR. In contrast, a high-normal T3 concentration increased the risk to have a big waist circumference, a high concentration of HDL-C, and insulin resistance. Diet analysis showed a high grade of malnutrition in women from all groups. The intake of calories was positively affected by the T3 concentration, albeit it did not affect the extent of malnutrition.
  
  
  CONCLUSIONS
  In contrast to concentrations of TSH, total thyroxin (T4), and free T4, the concentration of serum T3 was strongly correlated with cardio-metabolic variables in euthyroid postmenopausal women. In comparison to women without MetS, a high-normal serum concentration of T3 in women with MetS is positively associated with reduced glycaemia and CVR but negatively related to body mass index (BMI), insulin, insulin resistance, and HDL-C. Although the analyzed population had a nutritional deficiency, both calories and iron intake were positively affected by the T3 concentration. Our results suggest the necessity of health programs monitoring T3 in old people in order to treat hyperglycemia, cardio-metabolic components, and the ageing anorexia.
authors.affiliation: Maestría en Ciencias Biológicas, Universidad Autónoma de Tlaxcala, Tlaxcala, México.
authors.forename: Fabiola
authors.initials: F
authors.lastname: Luna-Vazquez
authors.affiliation: Doctorado en Ciencias Naturales, Universidad Autónoma de Tlaxcala, Tlaxcala, México.
authors.forename: Rosalía
authors.initials: R
authors.lastname: Cruz-Lumbreras
authors.affiliation: Maestría en Ciencias Biológicas, Universidad Autónoma de Tlaxcala, Tlaxcala, México.
authors.forename: Julia
authors.initials: J
authors.lastname: Rodríguez-Castelán
authors.affiliation: Doctorado en Neuroetología, Universidad Veracruzana, Xalapa, México.
authors.forename: Margarita
authors.initials: M
authors.lastname: Cervantes-Rodríguez
authors.affiliation: Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Carretera Tlaxcala-Puebla Km 1.5., Tlaxcala, C.P. 90070 México.
authors.forename: Jorge
authors.initials: J
authors.lastname: Rodríguez-Antolín
authors.affiliation: Instituto de Salud Pública, Universidad Veracruzana, Xalapa, México.
authors.forename: Omar
authors.initials: O
authors.lastname: Arroyo-Helguera
authors.affiliation: Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Carretera Tlaxcala-Puebla Km 1.5., Tlaxcala, C.P. 90070 México.
authors.forename: Francisco
authors.initials: F
authors.lastname: Castelán
authors.affiliation: Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Carretera Tlaxcala-Puebla Km 1.5., Tlaxcala, C.P. 90070 México ; Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Coyoacán, México.
authors.forename: Margarita
authors.initials: M
authors.lastname: Martínez-Gómez
authors.affiliation: Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala, Carretera Tlaxcala-Puebla Km 1.5., Tlaxcala, C.P. 90070 México.
authors.forename: Estela
authors.initials: E
authors.lastname: Cuevas
keywords: Calorie intake; Cardiovascular risk; Hyperglycemia; Metabolic syndrome; Thyroid hormone; Thyrotropin