title: Testosterone, SHBG and risk of type 2 diabetes in the second evaluation of the Pizarra cohort study.
abstract: OBJECTIVE
  To evaluate the association between serum levels of testosterone, sex hormone-binding globulin (SHBG) and calculated bioavailable testosterone (bioT), and the risk of type 2 diabetes mellitus (T2D) in a prospective cohort from southern Spain (Pizarra study).
  
  
  METHODS
  The study was performed in the Pizarra Cohort Study, a prospective study started in 1995 with a follow-up of 11 years. Anthropometric and metabolic variables were measured at baseline and at 6 and 11 years of follow-up. Total testosterone (TT), SHBG and calculated bioT were determined at the 6-year follow-up.
  
  
  RESULTS
  The levels of TT and bioT in men were negatively associated with the risk of obesity, T2D and the metabolic syndrome. In women, the levels of TT and bioT were associated positively with the risk of insulin resistance. The levels of SHBG were associated negatively with the risk of T2D, obesity and insulin resistance in both men and women. For all groups, the association was higher at the 11-year follow-up.
  
  
  CONCLUSIONS
  Low levels of testosterone and SHBG increase the risk of T2D in men, and high levels of testosterone increase the risk of insulin resistance in women. The association between TT levels and the risk of T2D is not completely independent of other variables, such as exposure time, adiposity, insulin resistance or SHBG levels. This study also shows that the different responses between men and women are probably because of the protective effect of SHBG, levels of which are higher in women than in men.
authors.affiliation: Servicio de Endocrinología y Nutrición, Hospital Universitario Carlos Haya, Malaga, Madrid, Spain.
authors.forename: Federico
authors.initials: F
authors.lastname: Soriguer
authors.forename: Elehazara
authors.initials: E
authors.lastname: Rubio-Martín
authors.forename: David
authors.initials: D
authors.lastname: Fernández
authors.forename: Sergio
authors.initials: S
authors.lastname: Valdés
authors.forename: Eva
authors.initials: E
authors.lastname: García-Escobar
authors.forename: Gracia M
authors.initials: GM
authors.lastname: Martín-Núñez
authors.forename: Isabel
authors.initials: I
authors.lastname: Esteva
authors.forename: Mari Cruz
authors.initials: MC
authors.lastname: Almaraz
authors.forename: Gemma
authors.initials: G
authors.lastname: Rojo-Martínez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001682:Biological Availability; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism*; D013030:Spain; D013739:Testosterone / Q000097:blood*; D055815:Young Adult
chemical_list: D012738:Sex Hormone-Binding Globulin; D013739:Testosterone