Relationship Between Plasma Homocysteine, Folacin And Vitamin B12 Levels In Vascular Cognitive Impairment

PrefaceDementia affects around 7% of the general population older than 65 years, and 30% of people older than 80 years. In the studies of the gerontic dementias, vascular dementia(VaD) and Alzheimer disease (AD) are the most two frequent types.Vascular cognitive impairment (VCI) can be divided into three subtypes with the degree of severity and the clinical features: Vascular Cognitive Impairment No Dementia (VCIND) , Vascular Dementia and Mixed AD/ VaD. VCI is a concept which contains the changes of cognition with the vascular factors, containing the whole process of vascular cognitive impairment from light to heavy degree , it emphasizes the early discovery and prevention, has the practical clinical meaning.Recent studies have found that plasma homocysteine levels are closely associated with the occurrence of gerontic dementia, the purpose of this study was to investigate the relationship of plasma homocysteine levels and the two subtypes of VCI( VCIND and VaD ).Subjects and methods1. Subject:(1) VCIND group:22 patients of both sexes (16 male,6 female) ,mean age 72. 91 ± 4. 29,mean years of education 9. 40 ±2. 59. (2) VaD group:21 patients of both sexes ( 16 male,5 female ) , mean age 71. 34 ±4. 35 ,mean yearsof education 9. 52 ±3. 19. (3) healthy control group: 18 person of both sexes (14 male and 4 female) , mean age 72. 22 ± 5.42, mean years of education 9.72 ± 2. 51. All patients and control subjects were comparable for age , education level, sex distribution.2. Methods;( 1 ) Neuropsychologic examinations: mini - mental state examination (MMSE) , activities of daily living scale ( ADL) , Preffer outpatient disability questionnair( POD) , clock drawing test(CDT) , clinical dementia rating scale (CDR) , Hachinski ischemic scale (HIS) , center for epidemiological studies depression scale(CES -D). (2) Measurement of serum Hey, folacin and vitamin B12;plasma Hey was measured with fluorescence polarization immunoassay, tachyphylaxis analytical system and correlated reactant. Plasma folacin and vitamin B12 were measured with electrochemiluminescence analytical technique. (3 ) Measurement of carotid with color Doppler ultrasonograph;measure the inti-ma - media thickness (IMT) of posterior wall of the carotid.3. Statistics analysis: All data is displayed with mean ± standard deviation, compared measurement data with analysis of variance, t -test, compared numeration data with chi square test, regard the difference significant when P < 0.05.Results1. The difference of the scores of ADL,POD,CDR,HIS and CES - D were not significantly in the VCIND group and normal control group(P >0. 05) ,the scores of MMSE and CDT in the VCIND group were significantly lower than those in the normal control group ( P < 0. 05). The scores in the VCIND group were significantly lower than those in the normal control group in the aspects of place orientation , time orientation , attention and calculation, verbal recognition memory,writing ability,structure ability( P < 0. 05 ) .2. The plasma Hey levels were significantly increased in the two groups (divided according to the existence of cerebral infarction on MRI) as compared to normal control group, while the levels of folacin and vitamin B12 showed re-duced levels in the two groups . The plasma Hey levels were significantly increased in VaD group as compared to VCIND group(P <0. 05) , while the levels of folacin and vitamin B12 showed reduced levels in VCIND group( P <0. 05) . The plasma Hey levels were significantly increased in VCIND group than in the normal control group( P < 0. 05 ) , the levels of folacin and vitamin B12 in VCIND group were significantly lower than in the normal control group( P <0. 05) .3. The scores of MMSE in the IMT < 1. 0mm group were higher than in the IMT > 1. 0mm group( P <0. 05 ).Conclusions1. High level of Hey can induce cognitive impairment with no dementia, e-ven higher level Hey can induce the development of VaD. High level of Hey induce the development of the cognitive impairmet may be depended on not only the vascular lesion,but also the neurotoxicity.2. The drug Intervention with folacin and vitamin B12 to the patients with high level Hey may achieved the purpose of treating the dementia or delaying the progression of disease.3. The more severity of carotid artherosclerosis, the poor scores of cognition-al tests. Active intervention and treatment of carotid artherosclerosis may lesson the cerebral ischemic damage, and it is in favour of the restoration of cognition function and neurofunction.