Does vaginal estrogen increase risk of heart disease and some cancers?
Results of a new study in Menopause appear to indicate that postmenopausal women who use vaginal estrogen are not at increased risk of cancer and various other diseases like coronary heart disease (CHD), stroke, and deep vein thrombosis.
The researchers used data from participants in the Women’s Health Initiative Observational Study, which recruited from 40 US clinical centers. The women studied were aged 50 to 79 years at baseline and did not use systemic estrogen therapy during follow-up (n = 45,663, median follow-up 7.2 years). The authors collected data on CHD, invasive breast cancer, stroke, pulmonary embolism, hip fracture, colorectal cancer, endometrial cancer, death, and self-reported use of vaginal estrogen (cream, tablet). Adjustment for covariates was done with Cox proportional-hazards regression models.
Among women who had an intact uterus, risks of colorectal cancer, endometrial cancer, pulmonary embolism/deep vein thrombosis, and invasive breast cancer were not significantly different for use or nonuse of vaginal estrogen. Risks of CHD, all-cause mortality, global index events (GIEs), and fracture were lower among women who used vaginal estrogen than among the nonusers (GIE adjusted hazard ratio 0.68, 95% confidence interval 0.55-0.86). In women who had undergone hysterectomy, the risk of each GIE component and overall GIE showed no significant difference between users and nonusers (GIE adjusted hazard ratio 0.94, 95% confidence interval 0.70-1.26).
The investigators concluded that risks of cardiovascular disease and certain cancers were not increased in postmenopausal women who use vaginal estrogen.