Research Study On The Risk Factors For Vascular Cognitive Impairment And The Association With Cerebral Hemodynamics

Background:With the problem of population ageing becomes severe in China, the incidence of cerebrovascular disease and dementia shows a rising trend.Vascular dementia (VaD), following Alzheimer’s disease (AD), represents the second most common cause of dementia. In recent years, vascular cognitive impairment (VCI) has been one of the most popular research topics in the medical field with its yearly increased morbidity and early intervention, Which covers the whole pathogenesis of cognitive impairment caused by vascular factors. It promotes people to focus on the early diagnosis and treatment of VCI. A follow-up study showed that about 50% patients vascular cognitive impairment with no dementia would translate into VaD within five years, and early intervention could delay or prevent its progression. Therefore, it is of great significance to screen VCI as early as possible.Objectives:To assess the risk factors in patients with vascular cognitive impairment(VCI) secondary to ischemic cerebrovascular disease, analyze the characteristics of impaired cognitive functions in patience with VCI, and explore the correlation between cerebral hemodynamics and cognitive function.Methods:We retrospectively investigated patients with ischemic cerebrovascular disease in Department of Neurology, Affiliated Zhongda Hospital of Southeast University from February 2015 to February 2016. A total of 91 patients who met the inclusion criterias were finally enrolled in our study. The enrolled patients’ demographic datas (age, sex, education level) and cerebrovascular disease risk factors (history of smoking and alcohol consumption, hypertension, diabetes, coronary atherosclerotic heart disease and atrial fibrillation, dyslipidemia) were gathered then. We assessed cognitive function of subjects with Montreal Cognitive Assessment. Based on MoCA score results, the patients were divided into normal cognitive function (MoCA≥26分) and cognitive dysfunction group(MoCA<26分), we analyzed the differences of demographic datas and cerebrovascular disease risk factors between the two groups. By transcranial doppler detection, we got mean velocity(Vm) and pulsatility index (PI) of intracranial arteries of each subject (Vm, PI were mean of bilateral test results). By comparison with MoCA scores, we implored the correlation between Vm, PI and cognitive function,and compared the differences of Vm、PI as well as the cognitive domain scoresg (including visuospatial and executive functions, naming, attention, language, abstract, memory and orientation) between the two groups.Result:Among the 91 patients with ischemic cerebrovascular disease included,58 developed cognitive dysfunction. The incidence was 63.74%. VCI were associated with older age (p<0.001), low levels of education (p<0.001) and heart disease (coronary atherosclerotic heart disease or atrial fibrillation) (p=0.037), and older age and low levels of education were independently associated with VCI. Gender, smoking, alcohol consumption, hypertension, diabetes, dyslipidemia had no significant effect on VCI secondary to ischemic cerebrovascular disease. In terms of MoCA scores, the differences in visuospatial and executive functions, naming, attention, language and memory between the two groups was statistically significant (P<0.05). The difference in PI of intracranial arteries between the two groups was statistically significant (p<0.05), and PI of normal cognitive function group were lower than that in cognitive dysfunction group. In addition, MCA-PI was negatively correlated with MoCA (p=0.032, r=-0.229), the higher the MCA-PI, the lower the MoCA score.Conclusion:Patients with VCI was associated with higher PI than that in the normal, and the higher the MCA-PI, the more severe cognitive impairment. VCI were associated with older age, low levels of education and heart disease (coronary atherosclerotic heart disease or atrial fibrillation), and older age and low levels of education are independent risk factors of VCI.Patients with VCI showed a wide range of cognitive domains dysfunction:including visuospatial and executive functions, naming, attention, language and memory, and visuospatial and executive functions were the most damaged.