According to the results of a study published in the journal Neurology, premenopausal women who have one or both ovaries removed face an increased risk of cognitive problems or dementia later in life. Use of hormone replacement therapy until the age of natural menopause appeared to reduce this risk.
Women at very high risk of developing breast or ovarian cancer as a result of a hereditary cancer syndrome have the options of undergoing close surveillance for the development of cancer or of undergoing prophylactic (preventive) surgery to remove the breasts and/or ovaries.
A bilateral prophylactic salpingo-oophorectomy (BPSO) is a surgical procedure in which both the ovaries and the fallopian tubes are removed. In addition to reducing the risk of ovarian cancer, this procedure also reduces the risk of breast cancer; hormones produced by the ovaries (such as estrogen) contribute to the growth of many breast cancers.
Because estrogen may have a beneficial effect on cognitive function, it’s possible that removal of one or both ovaries before menopause (when the ovaries are still producing estrogen) may have a negative impact on cognitive function. To explore this possibility, researchers conducted a study among 813 women who had one ovary removed before menopause, 676 women who had both ovaries removed before menopause, and a comparison group of 1,472 women who still had both ovaries.
Among the women who had one or both ovaries removed, the reasons for ovary removal were either treatment of a benign condition (such as ovarian cysts) or prevention of cancer. Women who already had cancer were excluded from the study.
The occurrence of cognitive impairment or dementia was assessed over a follow-up period of roughly 25 years.
- Removal of either one or both ovaries was linked with an increased risk of cognitive impairment or dementia. Risk was highest among the women who were the youngest at the time of their oophorectomy.
- Among women who had both ovaries removed before the age of 49, those who used hormone replacement therapy until at least the age of 50 did not have an increased risk of cognitive impairment or dementia.
The researchers conclude that unilateral or bilateral oophorectomy before menopause appears to increase the risk of cognitive impairment or dementia. Although use of hormone replacement therapy until the age of natural menopause may decrease this risk, an accompanying editorial notes that many questions remain about the relationship between estrogen therapy and cognition.