Reduction of Serum Testosterone Levels During Chronic Glucocorticoid Therapy

TLDR

The study examined the impact of chronic glucocorticoid therapy on serum testosterone levels in men with chronic pulmonary disease. Chronic glucocorticoid therapy lowered serum testosterone in older men, with a dose‑dependent inverse correlation, while gonadotrophin levels remained unchanged and GnRH responses were preserved, indicating suppression via altered hypothalamic GnRH secretion.

Abstract

The effect of chronic glucocorticoid therapy on serum testosterone levels was studied in men aged 67 ± 4 (SD) years with chronic pulmonary disease. The serum testosterone level was reduced in 14 of 16 patients to a mean value of 211 ± 93 ng/dL, compared with 449 ± 111 ng/dL in 11 age- and disease-matched control patients (p < 0.001). The corticosteroid dosage and the serum testosterone level were inversely related (r = -0.78). Testosterone binding to serum proteins was not significantly affected. Basal gonadotrophin levels were not elevated while their secretory responses to exogenous gonadotrophin-releasing hormone (GnRH) were intact. We conclude that glucocorticoid therapy commonly reduces serum testosterone levels in older men due to alteration of hypothalamic GnRH secretion.