Progression of brain white matter hyperintensities in asymptomatic patients with carotid atherosclerotic plaques and no indication for revascularization

Abstract

Background and aimsBrain white matter hyperintensities (WMHs) have been associated with an increased risk of ischemic stroke and considered as markers of brain ischemia. Progression of WMHs in asymptomatic patients with non-hemodynamically significant carotid plaque could represent a putative marker of plaque vulnerability. We prospectively evaluate progression and determinants of WMHs in this population. MethodsThis prospective study included 51 asymptomatic patients with carotid stenosis <70% that underwent brain magnetic resonance imaging scans at baseline and after a median follow up of 595 days (interquartile range 553–641 days). Patients (mean age of 69 years and 45% females) underwent baseline carotid computed tomography angiography, contrast-enhanced ultrasound for carotid plaque characterization and analysis of subsets of circulating lymphocytes and monocytes by flow cytometry. ResultsSeventeen subjects (33.3%) had carotid stenoses of 50–70% (Doppler flow velocity) while the rest had stenoses of <50%. In 25 (49.0%) patients, new WMHs, with 5 new lesions on average and a median volume of 134 mm3, were detected at follow-up. None of the plaque characteristics or of the circulating cellular biomarkers investigated were associated with the global and ipsilateral occurrence of new WMHs whereas, at multivariate analysis, female sex, hypercholesterolemia, and lower glomerular filtration rate (GFR) emerged as independent variables associated with new WMHs. ConclusionsHalf of the patients with carotid plaques of intermediate severity had evidence of WMH progression at follow up. Female gender and systemic factors such as hypercholesterolemia, and lower GFR, but not plaque characteristics or circulating cellular biomarkers, are associated with WMH progression.