Birth Control Pills May Raise Glaucoma RiskNov 21, 2013
New research suggests that women who use birth control pills for several years or longer should consider having their eyes checked more regularly as they get older. The pills may double a woman’s lifetime risk of developing glaucoma, which can lead to blindness if left untreated.
The researchers said their findings should not discourage women from using oral contraceptives, since the risk of glaucoma is fairly low. Doctors should be aware of the link, the researchers say, and the estimated 11 million women who take oral contraceptives should monitor their long-term eye health, The New York Times reports.
The new study examined data on 3,406 women over the age of 40 who were part of the National Health and Nutrition Examination Survey for years, the Times reports. The women underwent regular eye exams and answered questions about their reproductive health and medical histories. Women who had used any type of birth control pills for three years or longer had a 5 percent risk of developing glaucoma, compared with a risk of about 2.5 percent in the general population, said Dr. Shan Lin, a professor of clinical ophthalmology and the director of the glaucoma service at the University of California, San Francisco medical school. Dr. Lin presented the findings this week at a meeting of the American Academy of Ophthalmology in New Orleans.
It is not clear why oral contraceptives might play a role in glaucoma, but earlier research suggests that the pills may interfere with cells in the optic nerve believed to play a role in protecting the eyes from age-related decline by depressing estrogen levels, the Times reports. Researcher previously found that women who experience early menopause or take estrogen-blocking medications, like drugs used against breast cancer, also have an elevated risk of glaucoma.
Dr. Lin cautioned that his findings were preliminary and showed a correlation, not causation. But, Lin said, these findings, taken together with data from previous studies, suggest that there is a relationship between estrogen levels and the development of eye disease, according to the Times.