Background. Age and androgens are key determinants of benign prostate hyperplasia (BPH) but the mechanisms remain unclear. We examine the relationship between androgens and total, central and peripheral prostate volume with a focus on early life factor.

Methods. A cross-sectional observational study of 406 community-dwelling Australian men aged 20 to 82 yr old without known prostate disease. Prostate zonal (total, central and peripheral) volumes were measured by planimetric transrectal ultrasound. Participants completed questionnaires, underwent physical examination and provided blood samples to measure total, free and bioavailable testosterone, dihydrotestosterone, estradiol, SHBG, LH, FSH and prostate-specific antigen (PSA).

Results. Prostate zonal volumes were positively associated with age, PSA, early onset of puberty, current height, body surface area (BSA), lean body mass, hip and waist circumference as well as recalled height and weight during puberty and adolescence but not current weight, fat mass or BMI. Stepwise multivariate regression modeling indicated that age and height were the only independent predictors of prostate zonal volumes. When adjusted for age and sampling time of day, the negative correlations of age-adjusted prostate zonal volumes with current blood total, free and bioavailable testosterone and the positive correlation with blood SHBG, were no longer significant.

Conclusions. This study suggests that early and long-term androgen exposure may have long-acting effects on mature prostate zonal volumes whereas relationships with current blood androgens and related hormones levels were mostly due to confounding by age. Further studies on the mechanism of androgen effects on late-life prostate diseases should consider lasting effects of early life androgen exposure.