The University of Eastern Finland has found an association between postmenopausal estrogen-based hormone therapy and a decreased risk of Alzheimer’s disease. Alzheimer’s is one of the most prevalent forms of dementia, especially among women, so these findings indicate that the female sex hormones—estrogen and progesterone—may be useful in preventing its onset and preserving cognitive ability in women.
This link was discovered using a variety of studies that followed approximately 230,000 Finnish women that were undergoing long-term postmenopausal estrogen-based hormone therapy over the course of 20 years. This long-term use of hormone replacement therapy was linked with better global cognition and episodic memory, as well as a lower risk of developing Alzheimer’s.
However, short-term use was found to have no significant impact on the risk of dementia, meaning the treatment’s protective effects were only seen if done consistently over a long period of time. Also, one cohort displayed an increased risk of dementia after starting hormone therapy later in the postmenopausal period, meaning timing is also an important factor.
This research shows that long-term postmenopausal hormone therapy may be useful in preventing or slowing cognitive decline and the progression of dementia, so long as treatment begins at the right time.