Abstract Number: Esoc2026a1986 Carotid Wall Shear Stress Across Sex and Age in the General Population: The Rotterdam Study

Abstract Background and aims Arterial wall shear stress (WSS) plays an important role in the pathogenesis of atherosclerosis, however, population-level data on carotid WSS is limited. We used a novel pipeline to assess carotid WSS across sex and age in the general population. Methods Using a semi-automated computational fluid dynamics pipeline, we performed simulations on 1452 participants of the Rotterdam Study based on carotid magnetic resonance imaging. From the simulations, mean and 95th percentile WSS were determined in the common (CCA) and internal carotid arteries (ICA). Linear mixed models assessed differences in WSS by sex and 5-year age groups. Results We included 2322 carotid arteries from 1314 participants (mean age 71 years, 45.3% female). Of the initial sample, 14% of carotids were excluded due to imaging artefacts and 3% due to unsuccessful simulations. Mean and 95th percentile WSS were 0.52 (95% CI 0.52-0.59) and 0.91 (95% CI 0.88-0.93) Pa in the CCA, and 1.27 (95% CI 1.24-1.30) and 2.98 (95% CI 2.90-3.06) Pa in the ICA. In both carotid segments, increasing age was related to decreasing WSS for both sexes (p0.001), see figure. In the CCA, females showed higher WSS values compared to males (β=0.12Pa for mean and β=0.21Pa for 95th percentile WSS, p0.001). No interaction effect of sex and age was observed. Conclusions Using the novel pipeline, we found that carotid WSS varies by sex and age, with higher values in females in the CCA and a decrease in WSS with increasing age in both carotid segments. These findings provide population-based insights into carotid hemodynamics. Conflict of interest S.C.M. van Kuijk: nothing to disclose. D. Bos: nothing to disclose. A. Akyildiz: nothing to disclose. M.K. Ikram: nothing to disclose. J.J. Wentzel: nothing to disclose. Figure 1 - belongs to Results