Low carotid artery wall shear stress is independently associated with brain white-matter hyperintensities and cognitive impairment in older patients

Abstract Background & aims Brain white-matter lesions and cognitive impairment are increasing because of the increasing number of patients aged ≥80 y. Wall shear stress (WSS) plays a pivotal role as a fluid mechanical mediator in vascular reactivity and atherosclerosis. In this study, we investigated the associations among common carotid artery (CCA) WSS, white-matter lesions, and cognitive impairment in patients aged ≥80 y Methods We enrolled 384 patients aged ≥80 y. All subjects had CCA-WSS, brain white-matter hyperintensities (WMH), and Mini-Mental State Examination (MMSE) assessments and were divided into three groups using tertiles of mean and peak CCA-WSS. Results For groups classified by the tertile of mean CCA-WSS, WMH, and WMH fraction were decreased; the MMSE score increased from low to high in the respective groups. Differences in WMH, WMH fraction, and the MMSE score were significant between any two groups (all adjusted p