The effect of short-term estradiol therapy on cognitive function in older men receiving hormonal suppression therapy for prostate cancer.

OBJECTIVES To determine the effect of estrogen (E) alone (without the influence of testosterone (T)) on cognitive function in older men, using 17-beta micronized estradiol versus placebo in older men rendered hypogonadal (low T and E) by treatment for prostate cancer. DESIGN Short-term double-blind, randomized, controlled trial. SETTING An outpatient General Clinical Research Center. PARTICIPANTS Twenty-seven community-dwelling men aged 65 and older receiving neoadjuvant or established therapy with luteinizing-hormone releasing-hormone agonists for treatment of prostate cancer enrolled in a short-term randomized, controlled trial of 17-beta micronized estradiol versus placebo on the effect on biochemical markers of bone turnover. MEASUREMENTS Hormone levels, including E, T, and sex hormone-binding globulin; standardized neurocognitive tests, including measures of sustained attention, executive function, and memory; and questionnaires to assess subjects' perception of cognitive deficits and symptoms of depression. RESULTS There were no significant differences between patients receiving E or placebo on 15 of 17 neurocognitive measures and no significant differences in self-reported cognitive deficits or number of depressive symptoms. CONCLUSION Although studies have suggested that E replacement therapy may improve cognitive function, most notably memory performance in postmenopausal woman, there was no evidence in the present study that the addition of short-term E therapy was more beneficial than placebo in tests of cognitive performance in hypogonadal men.