Women who begin their period late or go through early menopause have an increased risk of dementia, a new study says.
Researchers from Kaiser Permanente in California found women who had their first menstrual cycle at age 16 or older were nearly 25 percent more likely to be diagnosed with the age-related brain disease.
And those who entered menopause prior to age 47 had an almost 20 percent greater risk of developing dementia.
‘This adds to a growing body of research that shows dementia doesn’t just happen when you’re 65 or older,’ Dr Keith Fargo, director of scientific programs and outreach at the Alzheimer’s Association, who was not involved in the study, told DailyMail.com.
‘And it shows that things that happen even when you’re a teenager can affect your dementia risk.’
An estimated 5.7 million Americans of all ages are living with Alzheimer’s disease in 2019. Of this number, two-thirds are women.
By 2050, this number is estimated to rise to almost 14 million, according to the Alzheimer’s Association.
Sufferers experience a decline in cognitive, behavioural and physical abilities and there is no cure.
Women are 50 percent more likely to develop dementia over their lifetimes than men.
‘It’s important to study any risk factors that are specific to women that could eventually lead us to potential points of intervention,’ said lead author Dr Paola Gilsanz, a staff scientist in the division of research at Kaiser Permanente.
For the study, published in Neurology, the team looked at more than 6,000 female Kaiser patients.
The participants underwent medical exams and completed questionnaires that asked when they had their first period, if they had gone through menopause and if they had had a hysterectomy, an operation to remove all or part of the uterus.
Next, researchers calculated each woman’s number of reproductive years.
About 42 percent of the women developed dementia later in life.
Researchers found women who had their first period at 16 years old or older were 23 percent more likely to develop dementia than those who had their first period at age 13 or younger.
The team also found that women who entered menopause before age 47 were 19 percent more likely to develop dementia than those who had it after age 47.
When it came to total reproductive years – the years from the first period until menopause – women with fewer than 34 years were 20 percent more likely to develop dementia.
Additionally, women who had undergone hysterectomies had an eight percent greater risk of dementia than women who didn’t have the procedure.
Dr Fargo says he doesn’t want women to view this risk as a reason to decide against getting a hysterectomy.
‘I don’t want to anyone to say: “I have to avoid a hysterectomy at all costs”,’ he said.
‘You can’t know why this or that happened. There are all sorts of other variables that determine who’s at risk of needing a hysterectomy and who has dementia risk.’
Although the researchers are not sure why a shorter reproductive window is linked to a higher dementia risk, they believe hormone levels may play a role.
Previous research has shown estrogen stimulates energy expenditure and has anti-inflammatory properties, which may increase the risk of a dementia diagnosis.
‘Estrogen levels can go up and down throughout a woman’s lifetime,’ said Dr Gilsanz.
‘Our results show that less exposure to estrogen over the course of a lifetime is linked to an increased risk of dementia.’
She added, however, that further studies are needed to account for factors that affect estrogen levels such as birth control and pregnancies.
Dr Fargo says that while women can’t necessarily control when their reproductive years begin and end, there’s plenty they can safely do to lower their dementia risk.
‘Exercise, make healthy eating choices, staying socially and mentally active,’ he said.
‘Not only have these things been proven to lower the risk, but have a whole host of other positive benefits as well.’
Culled from Dailymail.com