Testosterone and temperament traits in men: Longitudinal analysis.

Testosterone is the main male hormone that has been associated with various behavioral traits in humans and other animals. We investigated whether levels of total testosterone, free testosterone, and sex hormone binding globulin were associated with temperament traits in a population-based sample of Finnish men at two measurement times taken 6 years apart (n=686 in year 2001, n=727 in year 2007). Temperament was assessed using the Temperament and Character Inventory that consists of four temperament traits: novelty seeking, harm avoidance, reward dependence, and persistence.

Relation of total and free testosterone and sex hormone-binding globulin with cardiovascular risk factors in men aged 24-45 years. The Cardiovascular Risk in Young Finns Study.

Background: Total and free testosterone decrease gradually in men with advancing age but it is not completely known how lower levels of testosterone are related with various cardiovascular risk factors. We studied the levels of total testosterone, calculated free testosterone and sex hormone-binding globulin (SHBG), and their relations with cardiovascular risk factors in young Finnish men.

Methods: The study cohort consisted of 24-45-year-old men participating the Cardiovascular Risk in Young Finns Study in the follow-up surveys performed in 2001 (N=1024) and 2007 (N=991).