Table 2.

Baseline cardiovascular and cerebrovascular variables

	Model 1: Age			Model 2: Age and Sex					Model 3: Interaction (Age × Sex)
				Age		Sex
	P value	R 2	β	P value	β	P value	β	Combined R2	P value	R 2	β Males	β Females
Intracranial cerebrovascular parameters (n = 73, females = 39)
MCAv, cm/s	0.005	0.11	−0.29 ± 0.10	0.001	−0.33 ± 0.09	0.003	10.2 ± 3.3	0.21	0.41	0.22	−0.41 ± 0.13	−0.25 ± 0.14
CVCi, cm/s/mmHg	<0.001	0.33	−0.006 ± 0.001	<0.001	−0.007 ± 0.001	0.006	0.11 ± 0.04	0.37	0.80	0.37	−0.007 ± 0.002	−0.006 ± 0.002
CVRi, mmHg/cm/s	<0.001	0.30	0.016 ± 0.003	<0.001	0.016 ± 0.003	0.09	0.17 ± 0.10	0.33	0.49	0.34	0.014 ± 0.004	0.018 ± 0.004
PI, AU	0.29	0.016	0.001 ± 0.001	0.25	0.001 ± 0.001	0.42	−0.027 ± 0.033	0.025	0.002	0.14	−0.001 ± 0.001	0.004 ± 0.001
Cardiovascular parameters (n = 73, females = 39)
MAP, mmHg	<0.001	0.25	0.49 ± 0.10	<0.001	0.47 ± 0.10	0.15	5.20 ± 3.50	0.27	0.92	0.27	0.48 ± 0.14	0.46 ± 0.15
$\text{P}{\text{ET}}_{\text{C}{\text{O}}_2}$, mmHg	0.06	0.048	−0.09 ± 0.05	0.07	−0.10 ± 0.05	0.93	−0.15 ± 1.7	0.048	0.16	0.075	−0.16 ± 0.07	−0.02 ± 0.07
V̇e, L/min	0.28	0.02	−0.031 ± 0.03	0.31	−0.029 ± 0.03	0.57	−0.57 ± 0.9	0.02	0.45	0.03	−0.009 ± 0.04	−0.05 ± 0.04
Extracranial internal carotid artery parameters (n = 58, females = 31)
ICA diameter, cm	0.09	0.05	0.001 ± 0.001	0.08	0.002 ± 0.001	0.001	−0.09 ± 0.02	0.23	0.73	0.23	0.002 ± 0.001	0.001 ± 0.001
Peak systolic velocity, cm/s	0.31	0.02	0.08 ± 0.08	0.44	0.06 ± 0.06	0.07	5.4 ± 2.8	0.08	0.70	0.08	0.094 ± 0.12	0.03 ± 0.12
Mean blood flow, mL/min	0.14	0.04	2.9 ± 1.9	0.12	3.0 ± 1.9	0.38	−60.5 ± 67.9	0.06	0.24	0.08	0.91 ± 2.7	5.5 ± 2.8
Shear rate, s−1	0.48	0.009	−0.47 ± 0.65	0.34	−0.60 ± 0.62	0.007	59.2 ± 21.3	0.14	0.49	0.14	−0.17 ± 0.8	−1.0 ± 0.9

Values are means ± SD. Boldface indicates significant relationship (P < 0.05). Model 1 presents the relationship between age and the indicated variable. Model 2 presents the addition of sex to the model and the relationship between age and sex with the indicated variable. Model 3 indicates if sex moderates the relationship between age and the indicated variable, with individual unstandardized β Coefficients shown for males and females. In models 1–3, R² value reflects the full model. In models 1 and 3, β represents the unstandardized β coefficient representing the change in variable units for every year increase in age. In model 2, the β coefficient provides the difference in females vs. males in the variable units. CVCi, cerebrovascular conductance index; CVRi; cerebrovascular resistance index; ICA, internal carotid artery; MAP, mean arterial pressure; MCAv, middle cerebral artery velocity; $\text{P}{\text{ET}}_{\text{C}{\text{O}}_2}$, end-tidal carbon dioxide; PI, pulsatility index; V̇e, minute ventilation.