A recent study presented at the American Neurological Association’s annual meeting suggests a significant connection between hormone therapy (HT) for menopausal women and the risk of Alzheimer's disease. The findings indicate that women who commence hormone therapy within five years of entering menopause may experience a 32 percent lower risk of developing Alzheimer’s disease. Conversely, starting hormone therapy at age 65 or older, particularly if the treatment includes progestin, was associated with a 38 percent higher risk of developing Alzheimer's disease.

Hormone therapy, which aims to alleviate menopausal symptoms like hot flashes and sleep disturbances by supplementing lost estrogen and progestin, has seen a resurgence in recent years. It is available in various forms, including pills and patches, and can involve estrogen-only treatments, combinations of estrogen and progestin, or estrogen with selective estrogen receptor modulators (SERMs).

The treatment's past is marked by controversy, largely due to flawed preliminary findings from the Women’s Health Initiative (WHI) clinical trial in 2002, which initially linked HT to higher risks of serious health complications such as heart disease and stroke. However, subsequent research has re-evaluated the original data, clarifying that HT can be a safe option for women in early menopause. Modern understanding suggests that hormone therapy may also support heart health and bone density as women age.

The decision to undertake hormone therapy is highly individualized and should be made in consultation with a healthcare provider. While HT is considered a valuable option by many experts, it is not suitable for everyone, particularly women with a history of breast or uterine cancer, blood clots, stroke, or heart attack. Despite its potential benefits, only about 5 percent of American women use HT as of September 2024, a notable decrease from 26 percent in 1999.

Experts like Dr. Jessica Shepherd, an ob/gyn, and Dr. Rhonda Voskuhl, a neurologist, emphasize the importance of discussing HT with a healthcare provider who understands its benefits and appropriate dosing. They highlight estrogen's protective role for multiple organ systems, including the brain, heart, and skin, and underscore that the decline in estrogen during menopause can hinder brain cell communication, reduce inflammation, and decrease protection against plaque formation linked to Alzheimer’s.

The proposed mechanism behind HT's potential protective effect on the brain is based on the