Menopause linked to Alzheimer’s-like brain changes

Menopause is linked to changes in the brain similar to those seen in Alzheimer’s disease, according to a large British study.

Loss of gray matter in areas involved in memory and emotion could partly explain why women are generally at greater risk of dementia than men, researchers speculate.

The results come from nearly 125,000 women, 11,000 of whom underwent brain MRIs.

In the study published in the journal Psychological Medicine, the use of hormone replacement therapy (HRT) did not appear to prevent gray matter loss.

Lead author Professor Barbara Sahakian, from the University of Cambridge, said: “The regions of the brain where we observed these differences are those that tend to be affected by Alzheimer’s disease.

“Menopause could make these women vulnerable later. While that’s not all, it may help explain why we see almost twice as many cases of dementia in women as in men.”

Brain changes occurred in:

• an area that plays a major role in learning and memory – the hippocampus
• a region essential for the formation of memories and spatial navigation – the entorhinal cortex
• a part that helps with attention and regulating emotions – the anterior cingulate cortex

Both white matter and gray matter are essential parts of the brain and spinal cord.

Gray matter is made up of neuronal cell bodies and their dendrites – short protrusions that communicate with nearby neurons.

White matter is made up of long axons of neurons that transmit impulses to more distant regions of the brain and spinal cord.

According to NHS guidelines, HRT may be considered for menopausal symptoms such as sleep problems and hot flashes.

According to researchers, the effects of menopause and HRT use on the brain, memory and mood are limited.

The study found that women on HRT were more likely to suffer from poor mental health. But many of them already had worse mental health before they were prescribed the drug.

Co-researcher Dr Christelle Langley said it was important to recognize the variety of difficulties that can accompany the menopause.

“We all need to be more sensitive to not only the physical, but also the mental health of women during menopause.

“There should be no shame in letting others know what you are going through and asking for help.”

Professor Channa Jayasena, a hormone expert from Imperial College London, said: “The effect of HRT on brain health during menopause continues to be a subject of debate, and past clinical trials like the Women’s Health Initiative have failed to answer this question.

Michelle Dyson, of the Alzheimer’s Society, said women make up around two thirds of people living with Alzheimer’s in the UK.

“And while we don’t yet fully understand why they are more sensitive than men, it is thought that hormones could play a role,” she said.

“This large study adds to the evidence demonstrating the impact of menopause on the brain, including physical changes such as loss of brain volume.

“But without long-term follow-up of participants, to check whether they later develop dementia, we cannot be sure whether these brain changes associated with menopause also increase the risk of dementia.”

She said exercising regularly, not smoking and limiting alcohol intake could help reduce the risk of dementia.