Longer estrogen exposure ties to 8% lower brain-vessel disease odds

A Neurology study published Nov. 4 linked longer lifetime estrogen exposure to fewer signs of brain small-vessel disease in 352 cisgender women averaging age 70.

In the Nov. 4 study, menopausal hormone therapy was also associated with fewer small-vessel disease markers and better white matter integrity, a brain wiring measure. The result is observational, so it cannot establish whether hormone therapy changes dementia risk.

The researchers used data from the Gothenburg H70-1944 Birth Cohort, a longitudinal study of people born in 1944 and living in Gothenburg, Sweden. The final analysis included women without neurological disorders and with reliable self-reported information on reproductive history and hormone exposure.

Estrogen exposure was estimated from structured interviews covering age at first menstruation, age at menopause, whether menopause was surgical or natural, oral contraceptive use and menopausal hormone therapy use. The study did not measure hormone levels directly.

Participants had brain magnetic resonance imaging at baseline and again five years later. Women with a longer reproductive life span had about 8% lower odds of having two or more signs of small-vessel disease, with later menopause appearing to drive the association more than earlier menstruation.

Small-vessel disease refers to damage in the brain’s smaller blood vessels and is often assessed on imaging. The study also reported that hormone therapy users tended to have fewer signs of this damage and stronger white matter microstructure.

The associations differed by APOE-ε4, a genetic variant linked with higher Alzheimer’s disease risk. Among carriers, hormone therapy was associated with greater cortical thickness in Alzheimer’s-vulnerable brain regions; the same association was not seen in non-carriers.

Dung Trinh, an internist at MemorialCare Medical Group and chief medical officer of Healthy Brain Clinic in Irvine, Calif., who was not involved in the study, told Healthline that estrogen influences communication between brain cells, glucose use, neurotransmitters, blood vessels, inflammation and oxidative stress.

Sherry Ross, an OB/GYN and women’s health expert at Providence Saint John’s Health Center in Santa Monica, Calif., who was also not involved, told Healthline that the results support an individualized approach. “The goal should be to individualize treatment based on a woman’s symptoms, medical history, and overall health rather than taking a one-size-fits-all approach,” Ross said.

The study cannot determine whether estrogen exposure or hormone therapy was linked to better brain aging independently of other factors. It relied on self-reported reproductive and treatment history, used that history as a proxy for estrogen exposure and studied a specific Swedish birth cohort, so the findings may not apply equally to younger women, people with neurological disease or broader populations.

The practical message is narrow: the research adds to evidence that timing, genetics and health history may matter when studying menopause treatment and brain aging. It does not change current dementia guidance or establish hormone therapy as an Alzheimer’s disease treatment.

Source: Healthline News, Nov. 15; Neurology study, Nov. 4.

Atlas360 reports health research and does not provide medical advice.