Abstract A133: Racial/ethnic differences in serum sex steroid hormone concentrations in a nationally representative sample of U.S. adolescent males

Abstract

Abstract Background: Contrary to the hypothesis that the racial/ethnic disparity in prostate cancer (PCa) has a hormonal basis, we did not observe a statistically significant difference in serum testosterone concentration between non-Hispanic black (NHB) and non-Hispanic white (NHW) adult men in the nationally-representative Third National Health and Nutrition Examination Survey (NHANES III), although NHB men had a higher estradiol level. Unexpectedly Mexican-American men (MA) had the highest testosterone level. In this study, we evaluated racial/ethnic differences in hormone concentrations during puberty, the time of prostate maturation. Methods: We measured serum testosterone, estradiol, and sex hormone binding globulin (SHBG) concentrations by immunoassay for 161 adolescent males aged 12–19 who participated in the morning examination of Phase I of NHANES III. Free testosterone and free estradiol were estimated. Geometric mean concentrations were compared by race/ethnicity using linear regression adjusting for age, Tanner (puberty) stage, percent body fat (%BF), waist circumference (WC), physical activity, smoking, and the other hormones. Results: In 12–15 year olds, MA males had the highest total and free testosterone concentration (MA vs NHB: P<0.05). In 16–19 year olds, the pattern for total testosterone was similar to that for younger adolescents, whereas free testosterone did not differ by race/ethnicity. In 12–15 year olds, MAs had the lowest total (MA vs NHW: P<0.05) and free estradiol. In 16–19 year olds, NHBs had the highest and MAs the lowest total and free estradiol levels (NHB vs MA: P<0.05). Conclusion: MA male adolescents had the highest testosterone and older NHB male adolescents had the highest estradiol levels, patterns similar to adult males in NHANES III. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A133.