Early menopause increases the risk of Alzheimer’s, study suggests
Women who go through the menopause early are more likely to develop Alzheimer’s at a younger age, new research suggests.
Those who experience the hormonal change in their early 40s develop symptoms of the memory-robbing disease almost two years before other patients.
Entering the menopause at around 45 is linked with 15 per cent more dementia-related brain damage than if it happens five years later.
Researchers from the University of California San Francisco explained that the sex hormone oestrogen – which dramatically declines during the menopause – is known to protect against cognitive decline.
Writing in the publication JAMA Neurology, the experts suggest the age at which a woman begins menopause could serve as an ‘early marker’ of Alzheimer’s ‘well before cognitive changes become apparent’.
For the study, researchers analysed data from more than 2,600 women in the US with an average age of 78.
Around two-thirds of participants experienced a natural, age-related drop in hormones, while the remainder had a surgical menopause – triggered by the removal of the ovaries, for example.
The women disclosed the age they became menopausal – 49, on average – and underwent regular memory and thinking tests.
Research has suggested that women are more likely to suffer dementia than men because they lose grey matter as they go through the menopause
Everyone experiences dementia differently. Use this checklist to help you make a note of your symptoms before you talk to your GP.
Researchers also conducted brain scans in hundreds of the participants in order to track changes over time.
Earlier menopause was associated with poorer cognitive outcomes, earlier Alzheimer’s onset and more rapid brain shrinkage in later life.
Specifically, women who experienced natural menopause at around 45 developed 15 per cent more age-related brain damage over a decade compared with those who started the menopause at 50, the researchers estimated.
The damage affected white matter, which is responsible for carrying messages between brain cells and known to dwindle when dementia develops.
Overall, the researchers estimated that women who went through the menopause ten years earlier than the average age of 49 had around 1.8 fewer years without an Alzheimer’s diagnosis than those whose menopause occurred a decade later.
Earlier menopause was also linked to a faster decline in episodic memory, the ability to remember events and experiences, as measured by yearly cognitive tests.
Surgical menopause was more strongly linked to Alzheimer’s risk and memory decline, while earlier natural menopause was more strongly linked to signs of brain ageing on scans.
The researchers suggested this could be because when both ovaries are removed, hormone levels drop dramatically, rather than gradually over time.
Researchers believe oestrogen helps protect the brain by supporting communication between brain cells, maintaining the protective coating around nerves and warding off inflammation.
Experts stressed, however, that the findings do not mean women who experience an early menopause will inevitably develop Alzheimer’s.
But they added, those who go through menopause early should be looking to mitigate their risk.
It comes as the Daily Mail and Alzheimer’s Society have partnered in a drive to beat dementia, which claims 76,000 lives each year and is the UK’s biggest killer.
The Defeating Dementia campaign aims to raise awareness of the disease, in an effort to increase early diagnosis, boost research and improve care.
Michelle Dyson, chief executive of the Alzheimer’s Society, said women account for around two-thirds of the 982,000 people living with dementia in the UK – of which Alzheimer’s is the most common type.
‘And while we still don’t fully understand why they are more susceptible than men, it is thought that hormones may play a role,’ she said.
‘There are steps that women – and men – can take today to reduce their risk of dementia and these include regular exercise, not smoking and reducing alcohol consumption.
‘If you’re worried about yourself or a loved one, Alzheimer’s Society’s dementia symptoms checklist is a helpful first step in starting a conversation with your GP.’
Menopause typically occurs between the ages of 45 and 55 and is when sex hormone levels drop permanently and periods stop.
The most common symptoms include hot flushes, sleep issues, mood swings and vaginal dryness. Up to 80 per cent of women are thought to suffer with these symptoms, while a quarter endure anxiety, brain fog and memory problems.
