Prevalence and Characteristics of Symptomatic Intracranial Atherosclerotic Plaques in People Residing at Middle and High Altitudes: A Preliminary Study

Abstract

Background: This study aims to determine how atherosclerotic plaque prevalence and characteristics vary between individuals residing year-round at middle and high altitudes who have intracranial atherosclerotic disease. Methods: We conducted a retrospective analysis of patient data from our hospital, focusing on individuals with cerebrovascular symptoms who underwent high-resolution vessel wall imaging (HR-VWI). Patients who had lived at an altitude of <2500 meters for an extended period were classified in group A (n = 91), while those residing at an altitude of ≥2500 meters were placed in group B (n = 75). We examined the differences in plaque prevalence and characteristics between these two groups. Results: The detection rate of basilar artery plaque was higher in group A compared to group B (16% vs. 7.6%, p = 0.036). Conversely, the detection rate of anterior cerebral artery plaque was significantly lower in group A than in group B (4% vs. 11.8%, p = 0.016). The eccentricity index (EI) was greater in group B than in group A (0.72 ± 0.11 vs. 0.68 ± 0.12, p = 0.012). The prevalence of intraplaque hemorrhage (IPH) was lower in group B than in group A (39.5% vs. 58.7%, p = 0.002). Conclusions: IPH prevalence was lower in patients residing at high altitudes than in those residing at middle altitudes. However, patients living at high altitudes had a higher EI compared to those residing at middle altitudes. These findings underscore the presence of disparities in the prevalence and characteristics of intracranial atherosclerotic plaques between individuals residing at medium and high altitudes. It is essential to account for these distinctions when diagnosing plaques.