Relationship between carotid atherosclerosis and cognitive impairment: a cross-seciional study based on a populaiion aged 40 years and older at high risk of stroke in a rural area of Xi'an City

Objective To explore the relationship between carotid atherosclerosis (CAS) and cognitive impairment in the stroke high-risk population aged 40 years and above in the rural area of Xi'an City and determine whether CAS is a risk factor for cognitive impairment. Methods In this study, stroke high-risk population found in the Community and Rural Population Stroke High-risk Group Screening and Intervention Project carried out in Huyi District, Xi'an City, from October 2014 to March 2015 were selected as the research subjects. Color Doppler ultrasound was used to evaluate CAS, and CAS was defined as:carotid intima-media thickness (CIMT) ≥1.0mm, or carotid arteries (including common carotid artery, carotid sinus, internal carotid artery, and external carotid artery) have atherosclerotic plaques, or carotid stenosis. Mini-Mental State Examination (MMSE) was used to assess cognitive function. The MMSE score lower than the cut-off value (illiteracy ≤17, primary school ≤20 points, and junior high school and above education level ≤24 points) is defined as cognitive impairment. The study population was grouped according to the presence of CAS or cognitive impairment; univariate difference test and bivariate logistic regression were used to analyze the relationship between CASandcognitiveimpairment. Results A total of 451 subjects were included in the analysis. The average age of the subjects was (58.7±9.83) years old, and 44.3% were female.Among them, 329 cases (72.9%) had CAS and 57 cases (12.6%)met the diagnostic criteria for cognitive impairment. The prevalence of cognitive impairment in CAS group was significantly higher than that in non-CAS group (14.6%vs. 7.4%, P=0.041).Multivariate logistic regression analysis showed that cognitive impairment was significantly correlated with age (OR=1.121, 95% CI ：1.056-1.189, P＜0.001), but not with CAS (OR=1.008, 95%CI ：0.202-5.170, P=0.992). Conclusion No significant association between CAS and cognitive impairment was found in high stroke risk group aged 40 and above in rural areas of Xi'an.