A new international study has concluded that menopause at an early age is associated with an increased risk of dementia, and the study also showed that hormone replacement therapy after menopause was associated with a lower risk.
Menopause is a time point that occurs 12 months after a woman’s last menstrual period.
In the years before this point, women experience changes in their menstrual cycles, and they may suffer from hot flashes or other symptoms, which is called the “perimenopause” period.
The study was conducted by a research team from the University of Galway in Ireland and Boston University in the United States, and its results were published in the Journal of Alzheimer’s Disease on September 9, and the Eurek Alert website wrote about it.
It was conducted on 1,329 women who were in good cognitive health, through the Framingham Heart Study, to analyze the relationship between reproductive factors and signs of brain aging.
Increased exposure to estrogen during childbearing has been associated with enhanced cognitive performance and increased brain size.
Increasing the number of children a mother has had, higher blood estrogen levels, and older age at menopause were also associated with better performance on cognitive tests, specifically better visuospatial skills (i.e., the ability to perceive, analyze, and mentally manipulate visual and spatial information).
Longevity and reproductive health
Women have a greater risk of developing dementia than men, with women accounting for approximately two-thirds of those with Alzheimer’s disease.
The study looked at the woman’s age at her first menstrual period, the age at which menopause began, the length of her reproductive life, estrogen levels in the blood, and whether or not the woman used hormone replacement therapy after menopause.
These factors have been linked to performance on neurocognitive tests, signs of brain shrinkage on MRI scans, and a woman’s risk of developing dementia in the future.
Despite the health importance of this topic, understanding of the relationship between sex differences in Alzheimer’s disease and related types of dementia remains significantly behind compared to cardiovascular disease.
While women’s longer life expectancy may explain part of their higher risk, factors such as women’s reproductive health and hormone levels may also play an important role.