A new study suggests that women who undergo ovary removal before menopause, especially before the age of 40, experience a decrease in the integrity of the white matter in various parts of the brain later in life. White matter is the nerve fibers that connect neurons in different areas of the brain. The study’s findings are available online.Today in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, Michelle Mielke, Ph.D., professor and chair of epidemiology and prevention at Wake Forest University School of Medicine, stated that the removal of both ovaries before natural menopause can lead to sudden hormonal imbalances, which in turn raises the risk of cognitive impairment and dementia. She also mentioned that there have been limited neuroimaging studies to understand the underlying causes of this phenomenon.
In their study, the research team used data from the Mayo Clinic Study of Aging to identify women over the age of 50 with available diffusion tensor imaging.
The article discusses a study that used diffusion tensor imaging (DTI) to measure white matter in the brain. The study included 22 participants who had premenopausal bilateral oophorectomy (PBO) before the age of 40, 43 participants who had PBO between the ages of 40 and 45, 39 participants who had PBO between the ages of 46 and 49, and 907 participants who did not have PBO before the age of 50.
According to the study’s corresponding author, Mielke, females who had premenopausal bilateral oophorectomy before the age of 40 showed significantly reduced white matter integrity in multiple regions of the brain.
There were changes in certain areas of the brain where women aged 40-44 or 45-49 who had undergone PBO showed reduced white matter integrity, but many of these findings were not statistically significant. Mielke stated that 80% of participants who had their ovaries removed also had a history of estrogen replacement therapy. As a result, the study could not determine whether the use of estrogen replacement therapy after PBO lessened the impact of PBO on white matter integrity. She also noted that the ovaries produce hormones both before (mainly estrogen, progesterone, and testosterone) and after menopause (mainly testosterone).
When both ovaries are removed, there is a sudden decrease in estrogen and testosterone in women, which could explain the results,” Mielke explained. She also stated that more research is necessary to fully comprehend the connection between white matter changes and cognitive impairment.
“These findings are significant for women considering premenopausal bilateral oophorectomy for non-cancerous conditions, but we require a larger and more diverse group of women to confirm these results,” Mielke added.
