Carotid circumferential wall stress is not associated with cognitive performance among individuals in late middle...

Arterial remodelling aims at normalising circumferential wall stress (CWS). Greater CWS in the carotid artery has previously been associated with the prevalence and severity of cerebral small vessel disease, a major cause of ageing-related cognitive decline. Here we test the hypothesis that greater carotid CWS is associated with poorer cognitive performance.

We studied 722 individuals (60 ± 8 years, 55% men, 42.5% highly educated, blood pressure 137 ± 19/77 ± 11 mmHg, n = 197 with type 2 diabetes) who completed a neuropsychological assessment and underwent vascular ultrasound to measure the intima-media thickness (IMT) and interadventitial diameter (IAD) of the left common carotid artery at a plaque-free site. From IMT and IAD, lumen diameter (LD) was calculated. These structural measures were then combined with local carotid pulse pressure and brachial mean arterial pressure to obtain a measure of pulsatile (CWS_pulsatile) and average (CWS_mean) mechanical load on the vessel wall. Cognitive domains assessed were memory, executive function and attention, and processing speed.

After adjustment for age, sex, and education, regression analyses showed that neither CWS_pulsatile nor CWS_mean were associated with measures of cognitive performance (p-values ≥0.31). This null association did not differ by age or educational level, and was observed in both individuals with and without carotid plaque, diabetes and/or hypertension. In addition, none of the individual measures of carotid structure (i.e. IMT, IAD, and LD) was related to cognitive performance.

The present cross-sectional study shows that carotid CWS is not associated with cognitive performance, at least not among relatively highly educated individuals in late middle age with adequately controlled cardiovascular risk factors.