A study published in the Archives of Ophthalmology reports
that there is an association between women who take postmenopausal
hormones and the risk of developing age-related macular degeneration.
Diane Feskanich, Sc.D., (Brigham and Women’s Hospital and Harvard
Medical School, Boston) and colleagues found that, especially for women
who had taken oral contraceptives, postmenopausal hormones
reduced the risk of progressing to advanced stages of the eye disease.
Among older adults, age-related macular degeneration (AMD) is the chief
cause of blindness and loss of vision. The condition is responsible for
profound vision loss in 1.75 million
Americans.
“Although genetics plays a key role in susceptibility to AMD,
environmental factors, such as smoking, are also important,” write
Feskanich and colleagues. “Evidence of higher rates of AMD in women
than in men
and links between AMD and cardiovascular disease suggested a role for
estrogen,” in how the disease develops.
The researchers used data from the Nurses’ Health Study to analyze AMD
and factors related to estrogen such as postmenopausal
hormone use, oral contraceptive use, ages of menarche (first period)
and
menopause, and history of childbirth. Of the 74,996 post-menopausal
women in the sample, 554 and 334 developed beginning-stage and
neovascular AMD, respectively, between 1980 and 2002. The neovascular
stage of AMD is more advanced and results in the development of new
blood vessels.
The researchers found that, “Current postmenopausal hormone users had a
notable 48 percent lower
risk of neovascular AMD compared with those who had never used
postmenopausal hormones, although risk did not decline linearly with
longer durations of use. Risk was lowest for
postmenopausal hormone users who had used oral contraceptives in the
past.”
However, oral contraceptive use was not linked to early AMD risk, and
current postmenopausal hormone users were 34% more likely to develop
early stage AMD than non-users. “The higher risk of early AMD among
postmenopausal hormone users was unexpected and in apparent conflict
with the observed inverse association for neovascular AMD,” write the
researchers.
In addition, researchers found a 26% lower risk of early AMD among
women who had given birth.
The authors conclude that, “Taken together, these findings suggest a
role for estrogen in the
pathogenesis of AMD that requires further research in specific early
and late signs of disease.”
Menopausal and Reproductive Factors and Risk of Age-Related
Macular Degeneration
Diane Feskanich, ScD; Eunyoung Cho, ScD; Debra A. Schaumberg, ScD, OD,
MPH; Graham A. Colditz, MD, DrPH; Susan E. Hankinson, ScD
Archives of Ophthalmology (2008). 126[4]:
519-524.
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Here to View Abstract
: Peter M Crosta