Women who undergo a common yet invasive surgery before hitting menopause could be at an increased risk of dementia and general cognitive decline, according to new research. The study suggests that the prevalence of all forms of dementia is higher in women, with twice as many cases of Alzheimer’s disease compared to men.
This groundbreaking research could provide scientists with a deeper understanding of the underlying risk factors that make women more susceptible to these neurodegenerative diseases. The study scrutinised the brains of women who had their ovaries removed before reaching menopause and discovered a significant decrease in their brain health.
A reduction in the brain’s white matter can lead to cognitive decline and is closely linked to the effects of dementia. After analysing the MRI results of over 1000 women, researchers from Wake Forest University identified a connection between dementia and women who had undergone Bilateral Salpingo Oophorectomy (BSO), a procedure involving the removal of the ovaries.
Typically, women opt for this surgery pre-menopause to mitigate the future risk of ovarian cancer, a disease that claims the lives of more than 4000 Brits annually. Other reasons may include endometriosis and ovarian cysts. However, this latest research indicates that this routine procedure could have subsequent implications on brain health years down the line, reports Gloucestershire Live.
When a woman undergoes an operation to remove her ovaries, it alters the hormone cycle within her body, a change that typically doesn’t occur until menopause. Professor Michelle Mielke at WFU was intrigued to investigate if this observed correlation between hormone production and cognitive decline could also be evident in women who have had BSO.
So, what does this all mean?
Your brain is made up of two distinct types of matter: grey and white. In simple terms, your grey matter largely controls your movement and other brain functions, including memory, while your white matter transmits information and signals throughout your brain and to your nervous system.
Both these components of your brain are known to diminish with age, but can be severely impacted if you develop a form of dementia. Some forms, like Alzheimer’s disease, predominantly affect the grey areas of your brain, while others can cause your white matter to significantly shrink – leading to a decrease in your cognitive abilities.
The research discovered a strong association between ovary removal and those whose white matter had begun to shrink. Undergoing a BSO results in an “abrupt endocrine dysfunction. as a result of removing the ovaries” – something study lead Professor Mielke was keen to delve into further.
Of the 1011 MRI scans analysed, patients were categorised by age and whether they had undergone ovary removal surgery. A staggering majority of 907 women hadn’t had a bilateral salpingo-oophorectomy (BSO), while 22 underwent the procedure before turning 40, another 43 between the ages of 40 and 45, and 39 participants aged 46 to 49 had their ovaries removed.
Upon cross-referencing with the extensive MRI data, Professor Mielke discovered that women who had a BSO before hitting 40 experienced a more pronounced decline in white matter. The professor remarked: “Females who had BSO before the age of 40 had significantly reduced white matter integrity in multiple regions of the brain.”
Interestingly, the older women who underwent the surgery showed a lesser degree of white matter deterioration, which, although not the sole marker for conditions like dementia, is an important factor in the diagnostic process.
Dr Verna Porter delved into the reasons behind the impact of such surgeries on brain health, discussing with Medical News Today the importance of hormones like oestrogen and testosterone: “Both hormones contribute to overall brain health, influencing mood, cognition, and neuroprotection.”
They further explained the potential benefits of hormone therapy: “Oestrogen therapy, particularly when started soon after oophorectomy and within certain therapeutic windows, may help preserve white matter integrity and cognitive function.”
“Women who had their ovaries removed before age 40 showed reduced white matter integrity, which suggests an increased risk for cognitive impairment and dementia. This emphasises the critical role of ovarian hormone regulation in maintaining brain structure/ function, particularly in preserving white matter integrity.”