Elderly Women Regulate Brain Blood Flow Better Than Men Do

Abstract

Background and Purpose-Orthostatic intolerance and falls differ between sexes and change with age. However, it remains unclear what role cerebral autoregulation may play in this response. This study was designed to determine whether cerebral autoregulation, assessed using transcranial Doppler ultrasound, is more effective in elderly females than in males. Methods-We used transcranial Doppler ultrasound to evaluate cerebral autoregulation in 544 (236 male) subjects older than age 70 years recruited as part of the MOBILIZE Boston study. The MOBILIZE Boston study is a prospective cohort study of a unique set of risk factors for falls in seniors in the Boston area. We assessed CO 2 reactivity and transfer function gain, phase, and coherence during 5 minutes of quiet sitting and autoregulatory index during sit-to-stand tests. Pϭ0.002) in the autoregulatory band, implying less effective cerebral autoregulation. However, reduced autoregulation in males was not below the normal range, indicating autoregulation was intact but less effective. Conclusions-Female subjects were better able to maintain cerebral flow velocities during postural changes and demonstrated better cerebral autoregulation. The mechanisms of sex-based differences in autoregulation remain unclear but may partially explain the higher rates of orthostatic hypotension-related hospitalizations in elderly men. (Stroke.

Insights into the clinical management of the syndrome of supine hypertension – orthostatic hypotension (SH-OH): The Irish Longitudinal Study on Ageing (TILDA)

“…Again, these age and sex effects merit further investigation but, since they are not modifiable, were not the focus of our study. Previous studies have focused on sex-related differences in OI [53,54]. As regards the age effect, a previous study investigating the changing face of orthostatic and neurocardiogenic syncope with age found that symptomatic patients were significantly younger than asymptomatic [55], which is in keeping with our results.…”

Targeting secondary injury in intracerebral haemorrhage—perihaematomal oedema

“…69 Men are more susceptible than women to this dysfunction and, thus, might develop a greater volume of PHO. 77 A history of hypertension and lower systolic blood pres sure have been reported as independent predictors of PHO growth. 8 The former might relate to the effects of increased hydrostatic force on PHO, whereas the latter might reflect the contribution of blood pressure fluctuations to PHO formation.…”

Sex-specific risk of cardiovascular disease and cognitive decline: pregnancy and menopause

“…However, this may be due, in part, to the higher baseline cerebral blood flow velocity in women of any age group. Although autoregulation should prevent changes in blood pressure from altering cerebral blood flow, emerging evidence suggests that sex differences in dynamic autoregulation exist [133]. Therefore, sex differences in “true” cerebral vasodilator capacity, when accounting for baseline flow velocity and acute changes in blood pressure, and their underlying mechanisms are unclear.…”