Age, body mass index, race and other determinants of steroid hormone variability: the HERITAGE Family Study

Objective and methods: To investigate from the HERITAGE Family Study databa se, 13 steroid hormones (androstane-3 alpha. 17 beta -diol glucuronide, and rosterone glucuronide, cortisol, dehydroepiandrosterone (DHEA), DHEA ester (DHEAE), DHEA sulfate (DHEAS), dihydrotestosterone (DHT), estradiol, 17-hyd roxyprogesterone. progesterone, pregnenolone ester, sex hormone binding glo bulin (SHBG) and testosterone in each sex for their relationships with age, body mass index (BMI), race and key lifestyle variables. Sample sizes vari ed from 676 to 750 per hormone. Incremental regression methods were used to examine the contributions of the variables to steroid hormone variability. Results: Age was a major predictor for most steroid hormones. The greatest contribution of age was a negative relationship with DHEAS (R-2 = 0.39). BM I was also associated with the variability of several steroid hormones, bei ng the most important predictor of SHBG (R-2 = 0.20) and of testosterone (R -2 = 0.12) concentrations. When age and BMI were included, race still contr ibuted significantly to the variations in cortisol (R-2 = 0.02 for men and 0.04 for women), DHT (R-2 = 0.02 for men and 0.03 for women), and progester one (R-2 = 0.03 for women). Nevertheless, race appeared to be less importan t than age and BMI. In addition, lifestyle indicators (food and nutrient in takes, smoking and physical activity) influenced steroid hormone variabilit y. Their contributions, however, were minor in most cases once age, BMI and race had been taken into account. Conclusions: We conclude that age was th e most important factor, followed by BMI, race and lifestyle factors in exp laining steroid hormone variability.