"Add-back" Estrogen Reverses Cognitive Deficits Induced by a Gonadotropin-releasing Hormone Agonist in Women with Leiomyomata Uteri

Treatment of women with uterine myomas with GnRH agonists results in symptoms of hypoestrogenism which can be prevented by concurrent "add-back" estrogen administration. We took advantage of these induced endocrine changes to investigate their effects on cognitive functioning in young women with myomas. Nineteen women with uterine myomas were tested before treatment. They all received the GnRH agonist, leuprolide acetate depot (LAD), every 4 weeks for 12 weeks and were then randomized to receive LAD plus estrogen or LAD plus placebo every 4 weeks for 8 additional weeks. Levels of all sex hormones decreased after 12 weeks of LAD treatment (P < 0.01), and only estradiol (E2) levels increased (P < 0.01) following 8 weeks of subsequent treatment in the group that received LAD plus E2. Scores on neuropsychological tests of verbal memory decreased from pretreatment to 12 weeks posttreatment with LAD (P < 0.05). These memory deficits were reversed in the group that received LAD plus E2 for 8 weeks coincident with an increase in plasma E2, whereas memory scores remained depressed in the group that received LAD plus placebo. These findings are consistent with those from studies on surgically menopausal women and strongly suggest that estrogen serves to maintain verbal memory in women. These results provide support for the efficacy of add-back estrogen regimens in women treated with GnRH agonists and also imply that estrogen may be important for maintaining memory in the postmenopause.