In their review article, Belmaker and Agam (Jan. 3 issue)1 examine several mechanisms involved in depressive disorders, but they do not mention evidence that androgen-deprivation therapy, which is frequently used in the management of prostate cancer, can cause major depression.2 The mechanisms underlying this association may include loss of sexual potency, fatigue, cognitive impairment, and changes in body composition, which lead to deterioration of a patient's perception of his body.3 A direct effect of testosterone, however, cannot be ruled out. A cross-sectional study of the relation between testosterone levels and depressive symptoms in 856 community-dwelling older men showed that depression was inversely associated with bioavailable testosterone independently of age, weight change, and physical activity.4 Bioavailable estradiol was not associated with depressed mood.