Pericarotid fat density: a novel predictor of cognitive and functional outcomes in cerebral small vessel disease

Pericarotid fat density (PFD) obtained by computed tomography angiography (CTA) could serve as a surrogate biomarker reflecting local inflammation. The study aimed to quantitatively estimate the impact of PFD on cognitive and functional outcomes in patients with cerebral small vessel disease (CSVD).

A total of 71 symptomatic and 55 asymptomatic CSVD patients were prospectively recruited. Imaging characteristics comprising CSVD markers and carotid artery markers (PFD values, calcification, stenosis degree, ulceration, and maximum wall thickness) were analyzed. Cognitive assessments were performed 90 days after acute infarcts, including diverse neuropsychological scales (the Montreal Cognitive Assessment, the Shape Trail Test, the Stroop test, and the Rey-Osterrieth Complex Figure Test) and sensitive event-related potential (ERP) detection. Worse functional outcomes were defined as a Modified Rankin Scale change score (ΔmRS) ≥ 0 (ΔmRS = mRS_90-day-mRS_baseline) in the symptomatic CSVD cohort.

Symptomatic CSVD showed significantly higher PFD values than asymptomatic CSVD. As indicated by multiple scales and P3a/P3b amplitude, cognitive function in symptomatic CSVD was poorer than that in asymptomatic CSVD. Symptomatic CSVD showed numerically stronger correlations between PFD values and cognitive impairment, with more parameters involved and the strongest correlations existing among ERP data. Maximum PFD was identified as an independent predictor of adverse functional outcomes (p < 0.001), and a predictive model incorporating maximum PFD showed better performance (AUC = 0.939).

The increased PFD values were closely associated with cognitive impairment and adverse functional outcomes in CSVD patients, especially among those with symptoms. Our findings could assist in the risk stratification and tailored treatment of CSVD patients to facilitate prognosis.