Subnormal serum testosterone levels in male internal medicine residents

The consequences of sleep deprivation and stress in residency training have not been quantified. In the course of assembling a control group for other studies, we unexpectedly observed a significant (P < 0.005) and marked depression of serum testosterone levels in healthy male internal medicine residents (x = 20.6 ± 5.3 nmol/L, n = 7) compared with other hospital personnel (x = 11.8 ± 1.1 nmol/L, n = 18) Testosterone concentrations in the two groups were entirely nonoverlapping, while luteinizing hormone levels were not significantly different. We conclude that the stress of residency training leads to a quantifiable depression of gonadal function, and that gonadal steroid concentrations may be useful in evaluating measures intended to reduce that stress.