Menopause represents a major change in a woman's life and body, and researchers have long sought to determine whether hormonal shifts associated with "The Change" also influence what happens in the brain. Now, an analysis led by a researcher here shows that post-menopausal hormone levels are largely unrelated to cognition and mood. As I describe in a release:
For their study, [Victor Henderson, MD,] and his colleagues analyzed data on 643 healthy postmenopausal women who were part of the ongoing Early Versus Late Intervention Trial With Estradiol. The women, none of whom were on hormone therapy, ranged in age from 41 to 84.
They were sorted into two categories: those who had gone into menopause less than six years previously, and those who had gone into menopause more than 10 years previously. The researchers gave the women a series of neuropsychological tests to gauge their memory and overall cognition. Then, the researchers assessed them for depression and measured their levels of estradiol, estrone, progesterone and testosterone.
Based on the critical-window theory [i.e. that the effect of estrogen on cognitive aging might differ depending on when exposure occurs], along with results of past animal studies showing that the timing of estradiol replacement affects memory, Henderson said he and his colleagues had hypothesized that higher levels of estradiol would be positively associated with memory performance in women who had experienced menopause more recently but not those who had experienced it longer ago. "Instead, we found no significant link -- positive or negative -- in either group," he said.
The research is the first to investigate links between sex hormones and cognition in both younger and older postmenopausal women, and to determine whether the hormones affect women differently based on their age and how much time has elapsed since they reached menopause. Henderson told me the findings don't "necessarily mean that estrogens are irrelevant to cognition, since we have no way of measuring estrogen directly at the brain level. But they imply that boosting blood levels of estradiol or estrone -- even in younger postmenopausal women -- may not have a substantial effect on cognitive skills one way or the other."
The work (subscription required) appears online today in the Proceedings of the National Academy of Sciences.
Previously: No long-term cognitive effects seen in younger post-menopausal women on hormone therapy, Hormone therapy soon after menopause onset may reduce Alzheimer's risk and Studying ways to combat mental decline in aging