Hormone therapy associated with improved cognition

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. Multiple studies have previously 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.

The researchers 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.

Study results appear in the article "Lifetime estrogen exposure and cognition in late life: The Cache County Study."

"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.