Yan Lin

Diffusion tensor imaging changes correlate with cognition better than conventional MRI findings in patients with subcortical ischemic vascular disease.

Background/Aims: To investigate whether diffusion tensor imaging (DTI) is more sensitive than conventional MRI at detecting cognitive deterioration in patients with subcortical ischemic vascular disease (SIVD). Methods: Forty-two SIVD patients had a diagnosis of no cognitive impairment (NCI), vascular cognitive impairment/no dementia or vascular dementia (VaD). Whole-brain DTI histography and routine MRI were performed on these participants. Results: There were significant differences between cognitively impaired patients and NCI subjects in mean diffusivity and fractional anisotropy in either whole-brain white matter (WBWM) or in normal-appearing white matter (NAWM). All DTI indices within either WBWM or NAWM were found to be significantly correlated with both the attention-executive and memory measures in SIVD subjects. Lacune numbers and T2-weighted lesions correlated only with attention-executive measures, whereas hippocampal volumes correlated only weakly with memory measures. Whole-brain gray matter volumes correlated with Z scores for all cognitive domains but language. After VaD patients had been excluded from the analysis, cognitive measures remained significantly correlated with some of the DTI indices, but not with conventional MRI findings. Conclusions: Compared with conventional MRI, whole-brain DTI is a more reliable and sensitive technique for the early detection of cognitive impairment in SIVD patients.

Brief Screening for Mild Cognitive Impairment in Subcortical Ischemic Vascular Disease: A Comparison Study of the Montreal Cognitive Assessment with the Mini-Mental State Examination

Background and Purpose: To assess the validity of the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE) in the detection of vascular mild cognitive impairment (VaMCI) in patients with subcortical ischemic vascular disease (SIVD). Methods: Among 102 SIVD patients, both cutoff scores of the MMSE and MoCA for differentiating VaMCI from no cognitive impairment (NCI) or differentiating VaMCI from vascular dementia (VaD) were determined by the receiver operator characteristic (ROC) analysis. Optimal sensitivity with specificity of cutoff scores was obtained after the raw scores were adjusted for education. Results: After adjusting for education, the MoCA cutoff score for differentiating VaMCI from NCI was at 24/25 and that for differentiating VaMCI from VaD was at 18/19. After applying the adjusted MoCA scores from 19 to 24 to identify VaMCI in all SIVD patients, sensitivity was at 76.7% and specificity was at 81.4% (κ = 0.579). The adjusted cutoff score of the MMSE for differentiating VaMCI from NCI was at 28/29 and that for differentiating VaMCI from VaD was at 25/26. The sensitivity and specificity of the adjusted MMSE was at 58.1 and 71.2%, respectively, when using the score from 26 to 28 to identify VaMCI in SIVD patients (κ = 0.294). Conclusions: The MoCA detected subcortical VaMCI better than the MMSE.

Age- and Gender-Specific Prevalence of Risk Factors in Patients with First-Ever Ischemic Stroke in China

Background. Evidences are accumulating that age and gender have great impact on the distribution of stroke risk factors. Such data are lacking in Chinese population. Methods. 1027 patients with first-ever ischemic stroke (IS) were recruited and divided into young adult (<50 years), middle-aged (50∼80 years), and very old (>80 years) groups according to stroke onset ages. Vascular risk factors were collected and compared among groups. Results. Female patients were globally older than male patients at stroke onset and having higher prevalence of diabetes mellitus (DM), heart diseases, and atrial fibrillation (AF). However, females were less likely to drink heavily or smoke than males. Young patients had a much higher proportion of smoking and drinking than middle-aged and very old patients and the highest family history of hypertension, while very old patients had the highest prevalence of heart diseases and AF but lowest proportion of positive family history of vascular diseases. Hypertension and DM were equally frequent among three groups. Conclusion. Our study showed that vascular risk factors had a specific age and gender distribution pattern in Chinese IS patients. Secondary prevention strategy should emphasize on the control of different risk factors based on patients age and gender.

Early Use of Statin in Patients Treated with Alteplase for Acute Ischemic Stroke

Studies have reported that statin usage before stroke can increase the incidence of intracerebral hemorrhage after thrombolytic treatment. However, whether the administration of statin at an early stage of ischemic stroke increases hemorrhage occurrence is unknown. The aim of this study was to assess the effect of statin on neurological imaging and functional outcomes after intravenous alteplase treatment, within 24 h of acute ischemic stroke attack. A total of 119 consecutive acute ischemic stroke patients treated by intravenous alteplase were recruited, of which 71 patients (59.7 %) were given statin therapy within 24 h of stroke onset. The physiological parameters, including demography, vascular risk factors, and clinical characteristics were recorded. The occurrence of intracerebral hemorrhage (ICH), symptomatic intracerebral hemorrhage (sICH), 90-day functional outcomes, and mortality in the patients were further analyzed. There were 24 occurrences of ICH after alteplase treatment (20.2 %) and there was no difference when patients were treated with statin (p = 0.280). Multivariate logistic regression analysis showed no significant correlation between the administration of statin and the occurrence of ICH (p = 0.230) or sICH (p = 0.949). There was a trend toward better neurological function with higher statin dose. The use of statin in the early stage of ischemic stroke is safe and does not increase the risk of intracerebral hemorrhage after alteplase treatment, suggesting that a clinical trial of early statin treatment on a large scale following thrombolysis is needed for further evaluation.

Correlation analysis of the risk factors for subcortical vascular cognitive impairment

Objective Subcortical ischemic vascular disease (SIVD), characterised by multiple lacunar infarcts and white matter lesion (WML), has been considered as a major cause of subcortical vascular cognitive impairment (SVCI). The objective of the study is to identify the risk factors for SVCI in a group of SIVD patients who were registered in a stroke secondary prevention clinic. Methods Based on the detailed neuropsychological investigation and clinical interview, 61 cases that met the criteria of SIVD were recruited and classified as 3 groups of different cognitive state: no cognitive impairment (NCI), vascular cognitive impairment no dementia (VCI⁃ND) and vascular dementia (VaD). The latter two were further grouped as vascular cognitive impairment (VCI). Their demographic data, vascular risk factors and neuroimaging information were documented. Results 1) The total prevalence of VCI (VCI⁃ND and VaD) was 63.93% (39/61). The prevalence of VCI ⁃ ND and VaD were 36.07% (22/61) and 27.87% (17/61), respectively. 2) There were significant differences of age and educational years among NCI, VCI⁃ND and VaD groups (P = 0.032, 0.019). Paired comparison showed that VaD patients were older and less educated than NCI patients (P = 0.029, 0.022). The age difference between NCI and VCI groups nearly approached statistical significance (t = 3.740, P = 0.058), while the year of education of VCI was significantly lower than that of NCI (t = 7.888, P = 0.007). 3) There were significant differences of diabetes mellitus (DM) cases among NCI, VCI ⁃ ND and VaD groups (P = 0.037). There were more DM cases in VCI group than those in NCI group (P = 0.012), but no significant statistical difference was found among other vascular risk factors. 4) There was no difference of lacunar infarcts in different site of subcortical grey matter among these groups, respectively (P > 0.05, for all). Significant differences of subcortical white matter infarcts, WML scores and medial temporal atrophy (MTA) scores were found in patients in NCI, VCI⁃ND and VaD group (P = 0.020, 0.001, 0.000). The number of lacunar infarcts within white matter in VaD group was higher than that in NCI group (P = 0.027). The WML scores of VaD was much higher than that of VCI⁃ND and NCI (P = 0.001, 0.017). The MTA scores of VaD patients was much higher than that of VCI⁃ND and NCI patients (P = 0.001, 0.000). The number of white matter lacunar infarcts, the WML scores and the MTA scores of VCI was much higher than that of NCI (t = ⁃ 2.661, P = 0.003; t = ⁃ 2.953, P = 0.005; t = ⁃ 4.712, P = 0.000). 5) Logistic regression showed that DM, the number of white matter infarcts and MTA scores were independent risk factors for SVCI. Conclusion SVCI is common in SIVD patients and related to DM, ischemic and degenerative injuries of the brain. DOI：10.3969/j.issn.1672-6731.2010.03.012