Carotid intima media thickness and white matter hyperintensity volume among midlife women.

Introduction: Carotid atherosclerosis may be associated with brain white matter hyperintensities (WMH). Few studies consider women at midlife, a critical time for women's cardiovascular and brain health. We tested the hypothesis that higher carotid intima media thickness (IMT) would be associated with greater WMH volume (WMHV) among midlife women. We explored interactions by apolipoprotein E (APOE) ε4 status.

Methods: Two hundred thirty-nine women aged 45 to 67 underwent carotid artery ultrasound, phlebotomy, and magnetic resonance imaging (MRI). One hundred seventy participants had undergone an ultrasound 5 years earlier.

Results: Higher IMT was associated with greater whole brain (B[standard error (SE)] = 0.77 [.31], P = 0.01; multivariable) and periventricular (B[SE] = 0.80 [.30], P = 0.008; multivariable) WMHV. Associations were observed for IMT assessed contemporaneously with the MRI and 5 years prior to the MRI. Associations were strongest for APOE ε4-positive women.

Discussion: Among midlife women, higher IMT was associated with greater WMHV. Vascular risk is critical to midlife brain health, particularly for APOE ε4-positive women.