Patient follow-up 10 years after hormone replacement therapy treatment revealed there were no long-term negative cognitive effects.
Short-term hormone therapy lasting four years initiated within three years of the last menstrual cycle had no long-term cognitive effects when compared with placebo, according to new follow-up research done a decade later and published in PLOS Medicine yesterday.
A team of researchers led by Carey E. Gleason, Ph.D., geriatrics and gerontology professor at the University of Wisconsin, N. Maritza Dowling, Ph.D., associate nursing professor at George Washington University and Firat Kara, Ph.D., assistant professor of radiology at the Mayo Clinic used data from the Kronos Early Estrogen Prevention Study (KEEPS) in which 727 women were given a transdermal patch of estradiol or oral conjugated equine estrogens in addition to micronized progesterone for four years. The original KEEPS study was conducted from 2005 to 2008. Cognition was assessed at month 18, 36 and 48.
Roughly a decade later, in the recent KEEPS Continuation Study, which was conducted from 2017 to 2022, researchers identified 275 out of the original 727 women enrolled the first KEEPS study. The women then completed a series of cognitive tests examining memory, mental flexibility and visual and auditory attention, to determine if their four-year-long hormone therapy treatment had any long-term effects. The researchers determined there were none.
“These findings highlight the need for further research to explore other potential long-term health outcomes associated with [menopausal hormone therapy], beyond cognitive performance,” the researchers write in the study. “Future studies could focus on areas such as mood and Alzheimer’s disease biomarkers.”
Hormone therapies are a common choice for women in early menopause suffering from symptoms such as hot flashes, mood swings, sleep disturbances and sexual dysfunction, all due to a drop in estrogen. There has been ongoing debate about the health effects of these medications. A 2002 study linked hormone therapy to a significant increased risk for breast cancer, but a follow-up study published in May 2024 revealed that although breast cancer risk increased with longer use of combination hormone therapy, the absolute riskof developing breast cancer was relatively low, compared to placebo.The study also showed that estrogen only hormone therapy decreased breast cancer risk in women with prior hysterectomies.