Abstract 36: Hormone Replacement Therapy Increases The Risk Of Subarachnoid Hemorrhage In Post Menopausal Women
Background: The incidence of subarachnoid hemorrhage (SAH) increases after menopause and anecdotal data suggest that hormone replacement therapy (HRT) may reduce the rate of SAH and aneurysm formation in women.
Objective: To determine the effect of HRT on occurrence of SAH in a large cohort of women.
Methods: We analyzed the data for 93,676 women aged 50-79 years who were enrolled in the observational arm of the Women's Health Initiative Study. We determined the effect of HRT on risk of SAH over a mean period (±SD) of 12±1 years using Cox Proportional Hazards analysis after adjusting for potential confounders. We performed additional analysis to identify the risk associated with “estrogen only” and “estrogen and progesterone” HRT among women.
Results: A total of 114 (0.1%) of the 93676 participants developed SAH during the follow-up period. The rate of SAH was higher among women on HRT compared with those without HRT (0.14% versus 0.11%, p= <.0001). The rate was non significantly higher with “estrogen only” (32.5%) compared with “estrogen and progesterone” (18.4%, p=0.2) among women. The risk of SAH was higher among women on HRT compared to those without HRT (relative risk [RR] 1.5, 95% confidence interval [CI] 1.0_2.2) after adjusting for age, systolic blood pressure, and active cigarette smoking. The risk of SAH was higher among women on “estrogen only” HRT (RR 1.5 95% CI 1.0_2.2) and “estrogen and progesterone” HRT (RR 1.1, 95% CI 0.7_1.8).
Conclusions: Post menopausal women, particularly those at risk for SAH due to presence of unruptured aneurysms, family history, or cardiovascular risk factors, should be counseled against use of HRT.
Author Disclosures: O. Saeed: None. A.A. Malik: None. A.I. Qureshi: None.
- © 2015 by American Heart Association, Inc.