Vascular Health is Associated with Amyloid- in Cognitively Normal Older Adults

Journal of Alzheimer’s Disease 70 (2019) 467–475 DOI 10.3233/JAD-181268

Yumei Liu^a, Sophy J. Perdomo^a, Jaimie Ward^a, Eric D. Vidoni^b, Jason F. Sisante^a,c,Kiersten Kirkendoll^a, Jeffrey M. Burns^b and Sandra A. Billinger^a,∗

a Department of Physical Therapy and Rehabilitation Science, University of Kansas Medical Center,Kansas City, KS, USA
b University of Kansas Alzheimer’s Disease Center, Fairway, KS, USA
c Department of Physical Medicine and Rehabilitation, University of Kansas Medical Center, Kansas City,KS, USA

Abstract.
Background: Vascular health is closely related to Alzheimer’s disease (AD). Vascular function measured by flow mediated dilation (FMD) or pulsatility index (PI) can be used as marker of peripheral and central vascular health but is poorly characterized in those at risk for AD.
Objective: To assess the relationship of peripheral and central vascular function with amyloid- (A) and white matter lesion burden among cognitively normal older adults.
Methods: We enrolled participants 65 years of age and older. Using Doppler ultrasound, we assessed brachial artery FMD,and middle cerebral artery (PI). Global A burden, quantified using [18F] Florbetapir PET imaging, and white matter lesion volume (WML) were used as measures of AD pathology and vascular brain injury.
Results: After adjusting for age and cardiovascular risk factors, the data (n = 83) showed a negative association between FMD and A burden ( = –0.03, p < 0.001). FMD at a cut-off of 4.45% had 88% specificity and 75% sensitivity to elevated A (AUC= 0.86, 95%CI: 0.77–0.95). FMD was not related to WML volume (p = 0.8), and PI was unrelated to A burdenor WML volume (0 > 0.4).
Conclusions: Among cognitively normal older adults, blunted peripheral vascular function, as measured by brachial artery FMD, is associated with A burden. These findings provide support for further exploration into the pathophysiological relationship of vascular health and AD risk as measured by A.
Keywords: Amyloid- protein, pulsatile flow, transcranial doppler sonography, vascular endothelium

Vascular Health is Associated with Amyloid-β in Cognitively Normal Older Adults..pdf