Women who had their ovaries and fallopian tubes surgically removed before the age of 43 were 1.6 times more likely to develop glaucoma compared to women who had the procedure after that age, according to a report published in the April edition of the journal Menopause.
Glaucoma is the progressive deterioration of the optic nerve and can result in blindness. Because glaucoma is more prevalent among post-menopausal women than pre-menopausal women, researchers suspect that glaucoma may be related to the reduced estrogen level associated with life after menopause.
Removing the ovaries, which produce estrogen, is sometimes referred to as “surgically-induced menopause” because the estrogen levels in women who undergo this procedure drop similarly to levels in post-menopausal women.
“Glaucoma is disease we know is related to aging, and in women, many age-related diseases and conditions are related to the drop in estrogen levels that takes place after the onset of menopause,” said Dr. Thasarat S. Vajaranant, associate professor of ophthalmology, director of glaucoma services in the UIC department of ophthalmology and visual sciences and lead author of the study.
To study the effect of reduced estrogen levels and glaucoma, Vajaranant looked at women who had their ovaries and fallopian tubes removed before age 50, the average age of onset for menopause.
Vajaranant collaborated with researchers at Mayo Clinic led by Dr. Walter Rocca, professor of neurology and epidemiology, and co-director the Rochester Epidemiology Project. The study looked at data from 1,044 women who underwent bilateral oophorectomy (surgical removal of both ovaries and fallopian tubes) in Olmsted County, Minnesota between 1950 and 1987 who had the procedure before age 50, the average age of onset for menopause.
The average age of the women who underwent the procedure was 46 years old. None of the women had an estrogen-related cancer, such as breast or ovarian cancer, and none of the women were diagnosed with glaucoma before the procedure.
These women were compared to an age-matched control group of 1,070 women who did not undergo bilateral oophorectomy. Both groups were followed for an average of 26 years.
The researchers found that of the women who underwent oophorectomy, 14 percent developed glaucoma, and among the women who did not have the procedure, 12 percent developed glaucoma over the follow-up period.
Women who underwent oophorectomy before age 43 had a 60 percent increased risk of developing glaucoma compared to women who had the procedure after age 43.
Vajaranant believes that the increased risk for glaucoma among these younger women may be due to the longer period of time they experienced reduced estrogen levels.
Brandon Grossardt, Dr. Arthur Sit, and Dr. Lynne Shuster of the Mayo Clinic, Pauline Maki of the University of Illinois at Chicago, and Dr. Louis Pasquale of the Harvard School of Medicine were co-authors of the study.
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