Objective: Because studies have reported that higher birth weight is associated with higher prostate cancer risk later in life, we hypothesized that racial differences in utero affecting birth weight contribute to the racial disparity in prostate cancer risk. Leptin is a candidate for evaluating this hypothesis because it may influence fetal development, and levels in adulthood have been associated with prostate cancer risk in some studies.

Methods: Leptin concentration was measured by ELISA in venous cord blood collected from 70 African‐American and 37 white male full‐term births. Sex steroid hormones and insulin‐like growth factor (IGF) axis concentrations were measured previously. Separately by race, we calculated geometric mean leptin concentrations and estimated adjusted geometric means using linear regression.

Results: Leptin was positively correlated with birth (r=0.34) and placental (r=0.25) weights, IGF‐1 (r=0.21), and IGF binding protein (BP)‐3 (r=0.29) adjusting for race. Mean (± standard error) birth weight was lower (p=0.0011) in African‐American (3,237 ± 342 g) than white (3,477 ± 395 g) male babies. Unadjusted geometric mean leptin did not differ (p=0.92) between African Americans (5,280 pg/mL; 95% CI: 4,322–6,451) and whites (5,187 pg/mL; 95% CI: 3,938–6,832). However, adjusted geometric mean leptin was nonstatistically significantly higher (p=0.15) in African Americans (5,954 pg/mL; 95% CI: 4,725–7,502) than whites (4,133 pg/mL; 95% CI: 2,890–5,910).

Conclusion: We observed a non‐significantly higher adjusted cord blood leptin concentration in African‐American compared with white male babies, although unadjusted levels were similar. If our hypothesis were correct, we would have expected higher unadjusted leptin levels and birth weight among African‐American babies. Funding: NCI grants U54 CA091409, U54 CA091431, T32 CA009314; doctoral research fund, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B119.

Copyright © January 7, 2010, American Association for Cancer Research
2010