Carotid artery calcification score and its association with cognitive impairment

Abstract

Purpose

To retrospectively investigate the possible association between carotid artery calcification score (CS) and cognitive impairment in carotid artery stenosis (CAS) patients.

Patients and methods

Carotid artery was measured in 102 patients with cervical carotid arteries using Color Doppler ultrasound, multi-detector row spiral CT angiography and MRI scanning. Correlation analysis between CSs obtained by MD CT and cognitive scores was performed, and the correlation between CSs and vascular stenosis degree and MRI-measured plaque histological (lipid-rich necrotic nucleus [LRNC], intraplaque hemorrhage and fibrous cap surface rupture) and morphological parameters (lumen area [LA], wall area [WA], total area of blood vessels [TVA], plaque burden [PB]) was analyzed. Follow-up review analysis was conducted on 38 postoperative patients.

Results

Significant negative correlation was discovered between CS value and cognitive scores in CAS patients (R=−0.359, P<0.001), which did not exist in postoperative patients (P=0.348); CS value also showed significant correlation with WA (R=0.521, P=0.042), TVA (R=0.215, P=0.017) and PB (R=0.237, P=0.003) and had a certain predictive value for the occurrence probability of carotid plaque LRNC (P=0.029, AUC =0.780) in preoperative patients.

Conclusion

Carotid artery CSs have significant correlation with cognitive scores, which could be used as risk factor for early screening of cognitive impairment in CAS patients. The possible mechanism may be related to the calcification impact on the plaque burden.

Keywords:

• calcification score
• carotid artery stenosis
• cognitive impairment
• plaque burden

Disclosure

The authors report no conflicts of interest in this work.

Supplementary materials

A pre-experiment was executed to rule out personal error in data processing. Two qualified physicians not informed in advance were selected to process data analysis of the same ten samples, with results obtained from data paired sample test:

To avoid false positive results caused by CT scan box settings, all specimens of patients with CAS underwent calcium staining (Figure S1). Stained slices of calcium were sent to IMAGE PLUS quantization process; no significant difference was found between calcification score and calcium staining.

Figure S1 Carotid plaque calcium staining. Stained deposition of calcium presented as black annular, and plaque rupture occurred in the “right shoulder” of fibrous cap.

Table S1 Paired sample test results of the two physicians’ analysis

Table S2 Baseline characteristics of left and right CAS patients