High-risk carotid plaque and cognition: cerebral small vessel disease, statin intensity, and the asymptomatic paradox

We read with great interest the cross-sectional study by Masini et al.1 investigating the associations between high-risk carotid plaque features, covert brain infarcts and cognitive performance in patients with asymptomatic intermediate carotid artery stenosis. This work provides valuable multimodal imaging evidence for carotid atherosclerosis risk stratification. However, we suggest that the reported associations should be interpreted in light of three underdeveloped issues: the burden of cerebral small vessel disease (SVD), the intensity of lipid-lowering therapy, and the clinical meaning of ‘asymptomatic’ status in the presence of measurable cognitive impairment. First, the high burden of cerebral SVD in this cohort (71%) may have confounded the cognitive analyses. The authors attributed the lack of significant association between high-risk plaque features and cognitive performance to limited statistical power. However, an alternative explanation is the ‘masking effect’ of concomitant SVD. Emerging evidence establishes SVD as a primary driver of vascular cognitive impairment through mechanisms including blood-brain barrier disruption and chronic hypoperfusion.2 In a cohort where nearly three-quarters of participants have SVD, this diffuse microvascular pathology may obscure any specific cognitive contribution from focal carotid embolism. The observed visuospatial and memory impairments (60% and 31%, respectively) are more characteristic of SVD-related cognitive profiles than territorial embolic infarcts. Thus, future studies should adjust for SVD severity as a competing risk rather than a binary covariate.