Study On The Correlation Between Cerebrovascular Reactivity Detected By TCD And Mild Cognitive Impairment

Objective Mild cognitive impairment (MCI) is a syndrome with mild cognitive injuries not reaching dementia and normal total cognitive function and activity of daily life, caused by multiple reasons. It mainly divided into amnestic mild cognitive impairment(aMCI) and vascular cognitive impairment-no dementia(VCIND). It is a medium between normal aging and dementia. there are no effective therapeutic methods for all kinds of dementia, while MCI is the early stage of dementia that is recognizable and easy to intervene, it is the hotspot of study for professionals in many countries. Cerebrovascular reactivity (CVR) is a compensatory ability of cerebral micro vessels to maintain the stability of cerebral blood flow by vasodilation or vasoconstriction. Impaired CVR is concerned with dementia..Breath-holding index(BHI) is an index of CVR assessment. Our study aimed to making an attempt to provide the reference basis for that whether TCD with breath-holding test can be used in early study of MCI and for differentiation of aMCI and VCIND.Methods All object of study come from March2011to December2011in the first people’s hospital of changde. Using mini mental state examination(MMSE) and Montreal cognitive assessment(MoCA) packaging screening MCI.Then divided into the aMCI group with30cases,the VCIND group with30cases and the control group with30cases(matched for age,gender and educational level).Three groups carried out TCD with breath-holding test. Record the mean blood flow veclocity(MBFV) of middle cerebral artery(MCA) at the start and the end of breath-holding.Velocity trend graph recording and BHI calculation were performed. The features of BHI, MBFV and vascular risk factors were compared among the three groups.The relations of CVR and cognitive score were analyzed.Results1. Compared to the control group, BHI was significantly decreased in the aMCI group and the VCIND group(P<0.001), but there was no significant difference of BHI between VCIND and aMCI(P>0.05); Compared to the control group, MBFV was decreased in the aMCI group and the VCIND group, but there was no significant difference of MBFV among VCIND, aMCI and the control(P>0.05).2. BHI had positive correlation with MMSE and MoCA. The higher the MMSE and MoCA were, the higher the BHI was, and it was significant (P<0.001).3. There was significant difference of systolic pressure, fasting blood-glucose, total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol(LDL-C), triglyceride(TG), diabetes between the control group and the aMCI group or the VCIND group(P<0.05). But there was no significant difference between the aMCI group and the VCIND group(P>0.05).Conclusions1.Impaired CVR may be related to mild cognitive impairment;2.TCD with breath-holding test can not identify aMCI and VCIND;3.To assess the CVR by means of TCD with breath-holding test has important significance for early finding cerebral microvessel disease in MCI patient.