Aterosclerose Carotídea e Hipodensidades da Substância Branca: uma Relação Controversa

Abstract

Introduction:White matter hypodensities of presumed vascular origin, are recognized as an important cause of morbidity with established clinical and cognitive consequences. Nonetheless, many doubts remain on its physiopathology. Our goal is to clarify the potential role of carotid atherosclerosis and other vascular risk factors in the development of white matter hypodensities of presumed vascular origin. Material and Methods:We included patients that underwent CT brain scan and neurosonologic evaluation within a one-month period. Full assessment of vascular risks factors was performed. We seek to find independent associations between white matter hypodensities of presumed vascular origin, carotid intima-media thickness and vascular risk factors. Results: 472 patients were included, mean age was 67.32 (SD: 14.75), 274 (58.1%) were male. The independent predictors of white matter hypodensities of presumed vascular origin were age (OR: 1.067, 95% IC: 1.049 -1.086, p < 0.001) and hypertension (OR: 1.726, 95% IC: 1.097 -2.715, p = 0.018). No association was found between IMT (OR: 2.613, 95% IC: 0.886 -7.708, p = 0.082) or carotid artery stenosis (OR: 1.021, 95% IC: 0.785 -1.328, p = 0.877) and white matter hypodensities of presumed vascular origin. Discussion: Only age and hypertension proved to have an independent association with white matter hypodensities of presumed vascular origin. Carotid atherosclerosis, evaluated by IMT and the degree of carotid artery stenosis, showed no association with white matter hypodensities of presumed vascular origin. Since atherosclerosis is a systemic pathology, these results suggest that alternative mechanisms are responsible for the development of white matter hypodensities of presumed vascular origin. Conclusion: Age and hypertension seem to be the main factors in the development of white matter hypodensities of presumed vascular origin. No association was found between carotid atherosclerosis and white matter hypodensities of presumed vascular origin.

Are Cerebral White Matter Lesions Related to the Presence of Bilateral Internal Carotid Artery Stenosis or to the Length of Stenosis Among Patients With Ischemic Cerebrovascular Events?

“…In a large population-based study, the periventricular but not deep WMLs were significantly associated with an increased number of plaques in the carotid artery (20). On the other hand, several studies found no relation between carotid atherosclerosis and white matter lesions (15, 16). For example, Potter et al found no association between ipsi- or contralateral ICAS and WMLs, before or after adjusting for other risk factors and suggested that the association between ICAS and WMLs are due to these underlying risk factors (15).…”

“…Another pathophysiological mechanism explaining this association came from animal models with induced ICAS, where chronic hemodynamic impairment caused the delayed development of WMLs (13, 14). On the other hand, several studies found no relation between ICAS, and WMLs, and hence it was suggested that both are the result of the underlying risk factors like age or hypertension (15, 16). To explain these contradicting results, we speculate that special characteristics related to the ICAS might be related to the WMLs and hence in absence of these characteristics, ICAS would not be associated with WMLs.…”