Two weeks of transdermal estradiol treatment in postmenopausal elderly women and its effect on memory and mood: verbal memory changes are associated with the treatment induced estradiol levels

The present randomized double blind study investigated the effects of a 2 w eek transdermal estradiol treatment on memory performance in 38 healthy eld erly women. Cognitive performance was tested at baseline and after 2 weeks of estradiol or placebo treatment using verbal, semantic, and spatial memor y tests as well as a mental relation task and the Stroop. Initial results s howed no differences after treatment between placebo or estradiol treated s ubjects. However, within treatment group analysis revealed that estradiol t reated subjects who reached higher estradiol levels (larger than 29 pg/ml) performed significantly better after treatment in the delayed recall of the paired associate test (verbal memory) than subjects who reached lower estr adiol levels (P<0.05). A nonsignificant trend was observed for the immediat e recall condition (P<0.10) These findings were strengthened by correlation s between treatment-induced estradiol levels and changes in verbal memory p erformance. In addition, there was an association between estradiol levels and mood changes. However mood changes were not significantly associated wi th changes in verbal memory performance (P>0.20). The present study support s the idea that estradiol replacement has specific effects on verbal memory in healthy postmenopausal women, with delayed recall being more affected. It suggests that these effects can occur relatively rapidly, and that there may be a dose response relationship of estradiol to memory enhancement. Fu rthermore, the fact that these results were obtained in women who had been menopausal for an average of 17 years before entering the study indicates t hat the brain maintains a sensitivity for estrogens even after years of low estradiol plasma concentrations. (C) 1999 Elsevier Science Ltd. All rights reserved.