Menopause associated with increased dementia risk, research finds

A new international study led by University of Galway has found that entering menopause at an earlier age is associated with an increased risk of dementia.

The research also showed that hormone replacement therapy (HRT) after menopause appears to be associated with a reduced risk of dementia.

The research team from University of Galway and Boston University carried out the study with 1,329 cognitively healthy women from The Framingham Heart Study, to analyse the association between reproductive factors and markers of brain aging. It found:

1. Entering menopause at an earlier age is associated with an increased risk of dementia
2. HRT after menopause appears to be associated with a reduced risk of dementia
3. Greater exposure to oestrogen over the reproductive lifespan was associated with enhanced cognitive performance and larger brain
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5. Having more children, higher blood oestrogen levels and being older at the time of menopause were also associated with better cognitive test performance, specifically better visuospatial skills – the ability to perceive, analyse and mentally manipulate visual and spatial information.

Prof Emer McGrath, lead author and associate professor in medicine at University of Galway, and consultant neurologist, Galway University Hospital, said: “Our study explored the association between reproductive and hormonal factors across a woman’s lifespan and risk of brain aging. We looked at neurocognitive and neuroimaging markers from MRI brain scans, as well as cognitive test performance, including tests of memory, reasoning skills and visuospatial skills. We also looked at the future risk of dementia in relation to these reproductive factors. We found that entering menopause at an earlier age appears to be associated with an increased risk of dementia, while post-menopause HRT appears to be associated with a lower risk of dementia. Although our results suggest positive cognitive benefits of greater lifetime oestrogen exposure, they do require further validation.”

The research investigated the age at the time of a woman’s first period; the age at onset of menopause; the duration of a woman’s reproductive lifespan; levels of oestrogen and whether a woman used post-menopausal HRT or not. These factors were then related to performance on neurocognitive testing, MRI scans and a woman’s future risk of developing dementia.