Study Of Relationship Between Hyperhomocysteinemia With Cerebral Small Vessel Disease And Cognitive Function

Objective: To investigate the relationship between hyperhomocysteinemia withCerebral small vessel disease(SVD) and cognitive function.Methods: 142 patients and out-patients with SVD in the endoneural departmentwere selected from March 2005to May 2006. Which were divided into three groupsaccording to the head computer tomography: Lacunar infarction and Leukoaraiosisgroup (LA+LI) with 67 patients, Lacunar infarction group(LI) with 45 patients,Leukoaraiosis group(LA) with 30 patients. And 30 normal controls of similar age sexand education were selected. Plasma homocysteine (Hcy) and other risk factors weremeasured. Cognitive status was assessed wth Mini-Mental StateExamination(MMSE) and Clock drawing test.Results:1. Mean Hcy level in SVD group was 17.92μmol/L, which was significantlyhigher than control group of 10.76μmol/L (P＜0.05). Because ages were differentbetween LA+LI group LA group and LI group, covariance analysis was used toanalysis the mean Hcy level of three groups. LA+LI group mean Hcy level was25.15μmol/L.LA group Mean Hcy level was 16.87μmol.LI group mean Hcy levelwas 14.39μmol/L. Hcy level were higher in LA+LI group than LA group (P＜0.05)and Hcy level were higher in LA group than LI group(P＜0.05).2. Associations between Hcy levels, smoking history, history of stroke, historyof hypertension, diabetes, history of coronary heart disease and the presence of SVDwere shown in univariate analysis. Those factors as independent variables, enteredinto Multiple Logistic regression analysis. The results showed elevated Hcy level was an independent risk factor for SVD, odds ratio was 1.587. In addition, hypertensionand diabetes also were independent risk factors for SVD, odds ratio were 5.802 and6.341.3. To explore whether elevated Hcy level had different dangerous for differentSVD subtypes, Hcy, age, history of hypertension, smoking history, diabetes, coronaryheart disease history, stroke history as variables, to be entered Multiple Logisticregression analysis. Results showed that elevated Hcy level was risk factor for LAand LI, their odds ratio were 1.212 and 1.098 respectively.4. MMSE total score, orientation function, short-term memory, Language andCalculation function and Clock drawing test CDIS scores were significantly lower inpatients with SVD than in controls(P＜0.05). There was no significant difference inimmediate memory between SVD and controls. MMSE score and CDIS score werelower in LA+LI than LA group, and MMSE score and CDIS score were lower in LAgroup than LI group. There were no statistical difference in orientation and short-termmemory score between LA+LI group and LA group(P=0.241. P=0.262).Butorientation and short-term memory score in those two groups were lower than LIgroup (P=0.024,P=0.003). Attention and Calculation,language scores were lowerin LA+LI group than LA group and LI group (P=0.000. P=0.008).While those twocognitive functions were similar in LA group and LI group (P=0.535, P=0.609).Immediate memory had no significant difference among three SVD subtype groups.5. Multiple linear regression analysis was performed to explore the relationshipbetween Hcy and cognitive function. Hcy, age, sex, educational level, smoking, bloodpressure, glucose, kidney function as independent variables,MMSE scores and CDISscores as dependent variables. Multiple regression analysis result indicate that MMSEscore of SVD patients=45.771-7.314×log tHcy-0.171×age. CDIS score of SVDpatients=31.289-5.325×log Hcy-0.122×age. 6. To further explore whether elevated Hcy level was an independent risk ofcognitive function or not,Multiple Logistic regression analysis was performed. Theresults showed that after adjustment for age, educational level, history of stroke,leukoaraiosis, lacunar and other factors, elevated Hcy level was an independent riskfactor for cognitive impairment. For MMSE total score, orientation, Language,visual-spatial, executive respectively, odds ratio were 1.044,1.057,1.040 and 1.251.respectively. After adjustment for age,education level, history of stroke and otherconvertional vascular risk factors, elevated Hcy level was not an independent riskfactor for short-term memory and Attemion and Calculation.Conclusions:1. Elevated Hcy level is an independent risk factor for SVD.2. Elevated Hcy level may be more risk factors for LA compared for LI.3. Elevated Hcy level is an independent risk factor for cognitive functionimpairment and orientation, language and visual-spatial and executive functionimpairment. But not independent with short-term memory and attention andCalculation.4. LI patients with LA have more serious cognitive impairmen.