Age-specific population centiles for androgen status in men.

AIM The age-specific population profiles in men of circulating testosterone and its two bioactive metabolites dihydrotestosterone (DHT) and estradiol (E2) across the adult lifespan and its determinants are not well described. OBJECTIVE Our objective was to deduce smoothed age-specific centiles of circulating testosterone, DHT, and E2 in men using pooled data from population-based studies in three Australian cities from liquid chromatography-mass spectrometry steroid measurements in a single laboratory. DESIGN, SETTING, AND PARTICIPANTS We pooled data of 10 904 serum samples (serum testosterone, DHT, E2, age, height, and weight) from observational population-based studies in three major cities across Australia. MAIN OUTCOME MEASURES Age-specific smoothed centiles for serum testosterone, DHT, and E2 in men aged 35-100 years were deduced by large sample data analysis methods. RESULTS We found that serum testosterone, DHT, and E2 decline gradually from ages 35 onwards with a more marked decline after 80 years of age. Higher weight, BMI, and body surface area as well as shorter stature are associated with reduced serum testosterone, DHT, and E2. CONCLUSIONS Among Australian men, there is a gradual progressive population-wide decline in androgen status during male aging until the age of 80 years after which there is a more marked decline. Obesity and short stature are associated with reduced androgen status. Research into the age-related decline in androgen status should focus on the progressive accumulation of age-related comorbidities to better inform optimal clinical trial design.