Subarachnoid hemorrhage and the female sex: analysis of risk factors, aneurysm characteristics, and outcomes

Abstract

Object The pathophysiology of aneurysmal subarachnoid hemorrhage (aSAH) is unclear. Sex may play a role in the outcome of patients with aSAH. Methods The authors retrospectively identified 617 patients with aSAH (April 2005 to February 2010) and analyzed sex differences in risk factors (age, hypertension, smoking, alcohol consumption, and family history), admission-related factors (World Federation of Neurosurgical Societies grade and admission delay), aneurysm characteristics (site, side, location, and multiplicity), and outcomes (treatment modalities [coiling/clipping/both/conservative], complications [vasospasm and hydrocephalus], length of stay, and modified Rankin Scale score at 3 months). Results The female patients with aSAH were older than the male patients (mean age 56.6 vs 51.9 years, respectively, p < 0.001), and more women than men were ≥ 55 years old (56.2% vs 40.4%, respectively, p < 0.001). Women exhibited higher rates of bilateral (6.8% vs 2.6%, respectively, p < 0.05), multiple (11.5% vs 5.2%, respectively, p < 0.05), and internal carotid artery (ICA) (36.9% vs 17.5%, respectively, p < 0.001) aneurysms and a lower rate of anterior cerebral artery aneurysms (26.3% vs 44.8%, respectively, p < 0.001) than the men, but no side differences were noted. There were no sex differences in risk factors, admission-related factors, or outcome measures. For both sexes, outcomes varied according to aneurysm location, with odds ratios for a poor outcome of 1.62 (95% CI 0.91–2.86, p = 0.1) for middle cerebral artery, 2.41 (95% CI 1.29–4.51, p = 0.01) for ICA, and 2.41 (95% CI 1.29–4.51, p = 0.006) for posterior circulation aneurysms compared with those for anterior cerebral artery aneurysms. The odds ratio for poor outcome (modified Rankin Scale score of 4–6) in women compared with men after adjusting for significant prognostic factors was 0.71 (95% CI 0.45–1.11, p > 0.05). Conclusions The overall outcomes after aSAH between women and men are similar.

MRI Characterization in the Acute Phase of Experimental Subarachnoid Hemorrhage

“…Estrogen deficiency, such as after menopause, is associated with increased risk for SAH (60) and hormone replacement therapy is associated with decreased risk SAH as well as ameliorating subsequent brain injury (52, 58, 61). However, no significant difference of overall outcomes after aneurysmal SAH was found between women and men in another study, despite differences in age and aneurysm characteristics (53). In animal models of other central nervous system injuries, such as traumatic brain injury (62, 63), intracerebral hemorrhage (54, 64), or ischemic stroke (65), estrogen plays a neuroprotective role, leading to less brain injury.…”

“…The relationship between gender and cerebral hemorrhage has been examined previously both clinically (52, 53) and experimentally (54-56). We previously found that acute hydrocephalus occurs more frequently in female rats after SAH (6).…”

A magnetic resonance imaging grading system for subarachnoid hemorrhage severity in a rat model

“…Little is known about the relationships between gender and mechanisms of brain injury after SAH in clinical and experimental studies. In a clinical study, the overall outcomes between women and men were similar (Hamdan et al, 2014). In an experimental study, Friedrich and colleagues found that gender influences the impact of SAH with male rats having greater bleeding and worse brain injury in comparison to female rats (Friedrich et al, 2013).…”

Development of a statistical model for discrimination of rupture status in posterior communicating artery aneurysms

“…It is known that females have a higher incidence of aneurysms both in general and particularly in those located at the PCOM [16]. The association between gender and risk of aneurysm rupture, however, is not clear in the literature [18, 34].…”