Serum androgen levels in men:: Impact of health status and age

Objectives. To investigate the impact of health status on androgen levels in men and to assess the age-related changes in androgen levels. Methods. Sera were obtained from 526 men (age 20 to 89 years) participating in a health screening project and 35 men selected according to the SENIEUR protocol, which excludes those with underlying disease. The health screening project participants were divided into two groups: healthy men (n = 133; group 1) and the remainder (n = 393; group 2). The total testosterone and sex hormone-binding globulin levels were quantified, and the amount of free testosterone (cfT) was calculated. Results. The lowest annual declines in androgen level were observed in group 3 (testosterone 0.2%; cfT 0.4%), followed by group 1 (testosterone 0.4%; cfT 0.8%) and group 2 (testosterone 0.8%; cfT 0.9%). Body mass index and levels of cholesterol, triglycerides, and glucose correlated negatively (P <0.01) with testosterone and cfT. Decade-adjusted reference values (mean 2 standard deviations) for testosterone and cfT were defined. The proposed lower testosterone reference value declined gradually from 3.1 ng/mL (20 to 29 years) to 1.7 ng/mL (70 years or older). Conclusions. In this cross-sectional study, serum androgens declined in aging men, and the extent of this decrease correlated with health status. A fixed, non-age-adjusted reference value does not adequately reflect this and might lead to a false diagnosis of androgen deficiency, particularly in elderly men. The clinical value of age-related reference values, however, needs to be determined in prospective studies. (C) 2003, Elsevier Science Inc.