Plasma Estrogen Levels and Aneurysmal Subarachnoid Hemorrhage in Women

Objective: Aneurysmal subarachnoid hemorrhage (aSAH) is more prevalent in postmenopausal women, and it has been postulated that this relationship is hormonally driven by lower circulating levels of estrogens. We examined the association between circulating plasma estrogen levels and subsequent development of aSAH in women. Methods: Women from the Nurses' Health Study with confirmed aSAH (n = 38) were matched with controls (n = 38) on age, smoking, menopausal status, and other reproductive factors. Plasma estriol, estradiol, and sex hormone-binding globulin were measured at baseline, prior to the development of aSAH. Conditional logistic regressions were performed to assess the association between hormone levels and incident aSAH. Results: Plasma estradiol, estriol, and sex hormone-binding globulin were not associated with the subsequent development of aSAH. Women with a history of current or former smoking were associated with lower levels of circulating estriol (β = −0.35 ± 0.12, P = 0.004) and estradiol (β = −0.63 ± 0.16, P = 0.0002). Conclusions: In this study, we did not find an association between estrogen levels and the incidence of aSAH in women.