Emerging research suggests a longer period of estrogen replacement therapy provides a prolonged cognitive benefit. However, investigators acknowledge that the risk-to-benefit balance of hormone therapy use is complicated and must be individualized.
Research has determined that estrogen has a significant role in overall brain health and cognitive function. This knowledge has fostered various studies on the prevention of cognitive decline as related to reduced estrogen levels during the menopause transition.
The new study suggests a cognitive benefit from a longer reproductive window complemented with hormone therapy. The study, “Lifetime estrogen exposure and cognition in late life: The Cache County Study,” appears online in Menopause, the journal of The North American Menopause Society (NAMS).
Because women comprise two-thirds of the 5.5 million cases of Alzheimer disease in the United States, researchers have long suspected that sex-specific factors such as estrogen may contribute to women’s increased risk for the disease. Moreover, multiple studies have suggested a role for estrogen in promoting memory and learning.
In this newest study involving more than 2,000 postmenopausal women, researchers followed participants over a 12-year period to examine the association between estrogen and cognitive decline.
More specifically, they focused on the duration of a woman’s exposure to estrogen, taking into account such factors as time of menarche to menopause, number of pregnancies, duration of breastfeeding, and use of hormone therapy.
Investigators concluded that a longer duration of estrogen exposure is associated with better cognitive status in older adult women. Furthermore, they documented that these beneficial effects are extended with the use of hormone therapy, especially in the oldest women in the sample.
Women who initiated hormone therapy earlier showed higher cognitive test scores than those who started taking hormones later, providing some support for the critical window hypothesis of hormone therapy.
“Although the assessment of the risk-to-benefit balance of hormone therapy use is complicated and must be individualized, this study provides additional evidence for beneficial cognitive effects of hormone therapy, particularly when initiated early after menopause.
This study also underscores the potential adverse effects of early estrogen deprivation on cognitive health in the setting of premature or early menopause without adequate estrogen replacement,” says Dr. Stephanie Faubion, NAMS medical director.