Major Finding: Women who had ever used hormone therapy had a 14% higher risk for cataract extraction and current HT users had an 18% higher risk, compared with women who never used HT.
Data Source: A 98-month Swedish prospective study of 30,861 postmenopausal women.
Disclosures: Dr. Lindblad and her associates reported having no conflicts of interest related to the study, which was funded by Swedish government agencies and research foundations.
Women who used hormone therapy were more likely to need cataract surgery, a risk potentiated by drinking alcohol, a large Swedish prospective study found.
In a 98-month study of 30,861 postmenopausal women, those who had ever used hormone therapy (HT) had a 14% higher risk for cataract extraction and current HT users had an 18% higher risk, compared with women who had never used HT, in a multivariate adjusted analysis, Dr. Birgitta Ejdervik Lindblad and her associates reported. The study appears in the journal Ophthalmology (doi:10.1016/j.ophtha.2009.07.046).
Cataract extraction was even more likely in women who were using HT and drank alcohol. Among current HT users, any alcohol consumption was associated with a 29% higher risk for cataract extraction, and those who drank more than one alcoholic drink per day had a 42% higher risk, compared with women who were neither using HT nor drinking alcohol. (One drink was defined as about 13 g of alcohol, roughly equal to one glass of wine, bottle of beer, or drink of liquor.) Drinking alcohol has been associated with increased levels of plasma estrogen in postmenopausal women in prior studies.
Investigators collected data from women in the Swedish Mammography Cohort who completed questionnaires in September 1997 about hormone status, use of hormone therapy, and lifestyle factors. The researchers followed them through October 2005 and compared their names with those on Swedish registers of cataract surgeries, which identified 4,324 women who underwent cataract surgery during the study period.
Among women aged 65 years or older, the risk for cataract surgery was 73% higher in those using hormone therapy, compared with women who never used HT, after the researchers adjusted for the effects of alcohol consumption, smoking, diabetes, hypertension, steroid or vitamin use, body mass index, and education level.
Longer use of HT was associated with a higher risk for cataract extraction in a linear fashion, added Dr. Lindblad of the Karolinska Institute, Stockholm. Current users of hormone therapy reported a longer duration of HT (a mean of 6 years) compared with past users (4 years). Women who used HT for more than 10 years had a 20% higher risk of cataract extraction, compared with women who never used HT.
Dr. Lindblad and her associates advised caution in comparing their study with those conducted outside of Sweden because HT preparations and clinical practices vary between countries. Hormone therapy with estrogen alone is more common in the United States. And U.S. versions of HT for postmenopausal symptoms like hot flushes most commonly use conjugated estrogens alone or in combination with progesteronelike progestins, while in Sweden the predominant hormone therapy is a combination of estradiol with testosteronelike progestins. The different chemistries might have different effects on the body.