Abstract W P373: Resting Cerebral Blood Flow in Healthy Subjects Varies by Gender and Blood Pressure

Abstract

Background: Quantitative measurement of cerebral blood flow is a critical parameter in neurovascular research. Relatively little is known about factors altering resting CBF in healthy subjects. Methods: We performed the Anatomy and Cerebral Hemodynamic Evaluation of Migraine (ACHE-M) study, a prospective, observational, case-control study. Migraine with aura (MWA), migraine without aura (MwoA), and control subjects between the age of 25-50 were enrolled in a 1:1:1 ratio. Subjects with manifest vascular disease of any type were excluded. 3T arterial spin labeled perfusion MRI was performed to measure CBF. Blood pressure was measured with an automated cuff at study enrollment. As there were no differences in CBF between migraine and control groups, data were pooled for overall analysis Results: Mean age of the 156 included subjects was 33 ± 7 years; 78% were female. Baseline SBP was 126 ± 18 mmHg, and DBP 82 ± 12 mmHg. A history of hypertension was present in 4% of subjects. CBF (ml/100g/min) was similar between MWA, MwoA, and control subjects (MWA 51 ± 11, MwoA 51 ± 12, control 51 ± 11, p=0.97), but significantly higher in women compared to men (53 ± 11 vs. 44 ± 10, p <0.001). Global CBF was inversely related to SBP (r= -0.23, p=0.004) and DBP (r= -0.24, p=0.003). While global CBF declined with increasing age, this finding was not significant (r=-0.12. p=0.14). After adjustment for age and sex, the association between SBP and CBF was attenuated (p=0.32), however the association with DBP remained significant (p=0.01). Conclusions: Resting CBF is substantially higher in women than men, and inversely related to DBP. These critical factors must be considered in studies utilizing CBF measurement.