Menopause Linked to Reduced Brain Grey Matter in Large Study

Recent research has identified structural brain changes associated with menopause, based on findings from a large-scale study involving tens of thousands of women.

The University of Cambridge study analysed data from about 124,780 women, focusing on differences in brain structure between post-menopausal and pre-menopausal participants. The research found that post-menopausal women had lower grey matter volume in several brain regions, including the hippocampus, entorhinal cortex, and anterior cingulate cortex.

Approximately 11,000 women in the study underwent MRI scans to provide detailed assessments of brain structure. The study also recorded the average age of menopause onset at 49.5 years, with hormone replacement therapy typically starting at around 49 years among participants.

Researchers observed that post-menopausal women were more likely to report symptoms such as insomnia, fatigue, anxiety, and depression compared to those who had not yet reached menopause. The study further found that hormone replacement therapy did not stop the loss of grey matter, but it was associated with a slower decline in reaction times.

What the numbers show

• 124,780 women participated in the Cambridge study
• About 11,000 participants received MRI brain scans
• Average menopause onset was 49.5 years; hormone therapy began at 49 years

Additional research supports the link between menopause timing and brain health. A UK Biobank study involving over 154,000 post-menopausal women found that menopause before age 50 was linked to both lower grey matter indices and a higher risk of dementia from all causes.

Similar findings were reported in an Indian cohort study, where women who experienced menopause at or before age 45 had lower total grey matter and frontal lobe volumes, as well as poorer cognitive performance, compared to women with later menopause.

Observational studies have also indicated that greater lifetime exposure to estrogen, including longer reproductive periods, more pregnancies, and hormone therapy use, is associated with higher grey matter volume in brain regions that are vulnerable to Alzheimer’s disease.

According to the Alzheimer’s Society, women make up about two-thirds of people living with Alzheimer’s disease in the UK. This background provides context for ongoing research into how menopause and related factors may influence brain health in later life.

* This article is based on publicly available information at the time of writing.