Polly S. Richards

Frequency and Determinants of Poststroke Dementia in Chinese

Background and Purpose— Both dementia and stroke are major health problems in Chinese societies. Stroke is a frequent cause of dementia. Only a few studies have been published on poststroke dementia (PSDE), none of which has investigated a consecutive stroke cohort in Asian patient populations. The objective of this study was to examine the prevalence and clinical correlates of PSDE in Chinese stroke patients in Hong Kong. Methods— Two hundred eighty stroke patients consecutively admitted to the medical wards of a university-affiliated regional hospital were interviewed by a psychiatrist 3 months after stroke. The presence of dementia and vascular dementia was diagnosed according to the Diagnostic and Statistical Manual, 4th edition. In addition, a wide range of demographic and clinical variables were examined. Results— Fifty-five participants (20%) had PSDE. Univariate analysis found that PSDE was associated with age; level of education; prestroke Rankin Scale score; prestroke Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) score; National Institutes of Health Stroke Scale (NIHSS) best language score, dysarthria score, and total score; urinary incontinence; cortical infarct; leukoaraiosis; bilateral lesions; number of lesions; involvement of middle cerebral artery circulation; and cerebral atrophy index. Multivariate logistic regression suggested that prestroke IQCODE score, NIHSS total score, leukoaraiosis, involvement of middle cerebral artery territory, and cerebral atrophy index were independent risk factors of PSDE. After removal of 22 patients with prestroke dementia, which was defined as a prestroke IQCODE score ≥4.0, the frequency of PSDE dropped to 15.5%. Furthermore, involvement of the middle cerebral artery territory and cerebral atrophy index were replaced by level of education and bilateral lesions as independent predictors in the final logistic model. Conclusions— PSDE is common among Chinese stroke patients in Hong Kong. Its frequency is comparable to that in white populations. The clinical determinants of PSDE, after the exclusion of patients with prestroke dementia, include premorbid level of cognitive function, severity of stroke, leukoaraiosis, level of education, and bilateral lesions.

Poststroke Depression in Chinese Patients: Frequency, Psychosocial, Clinical, and Radiological Determinants:

This study attempted to evaluate the psychosocial, clinical, and radiological predictors of poststroke depression (PSD) in Chinese patients. One hundred eighty-nine patients participated in the study. Three months after the index stroke, a psychiatrist administered the Structured Clinical Interview for DSM-IV to all of the patients and made a DSM-IV diagnosis of depression. In addition, a host of demographic, clinical, and radiological variables were examined. Thirty-one (16.4%) of the patients had a diagnosis of PSD that included major depression (n = 11, 5.8%,), minor depression (n = 16, 8.5%), or dysthymia (n = 4, 2.1%). Univariate analysis revealed that PSD was associated with female gender, a lower level of education, a lower Lubben Social Network Scale (LSNS) score, subcortical infarcts, and lesions in the anterior cerebral artery (ACA) territory, and the Modified Life Event Scale (MLES) score was borderline for statistical significance. Multivariate logistic regression analysis suggested that female gender, a high MLES score, and subcortical and ACA lesions were independent risk factors for PSD and that a high LSNS score was a protective factor. (J Geriatr Psychiatry Neurol 2005; 18:45-51)

Frequency and determinants of prestroke dementia in a Chinese cohort

Abstract.Pre-existing dementia among patients with acute stroke is common, and adversely affects outcomes. Only a few studies have been published on prestroke dementia (PSD), none of which have investigated a consecutive stroke cohort in an Asian patient population. The objective of this study was to examine the prevalence and clinical correlates of PSD in Chinese stroke patients in Hong Kong.Close and reliable informants of 289 stroke patients who were consecutively admitted to the medical wards of a university-affiliated regional hospital completed the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) within 1 week after their relative’s admission. The presence of PSD was defined as an average IQCODE score of ≥ 4.00. In addition, a wide range of demographic and clinical variables were examined and recorded.Twenty-two participants (7.6%) had PSD. The frequency of PSD in the group of subjects (n = 73) who were assessed within 48 hours after their admission was 12.3%. Univariate analysis found that PSD was associated with age, marital status, atrial fibrillation (AF), previous transient ischaemic attack (TIA), leukoaraiosis, and cerebral atrophy index (CAI). Multivariate logistic regression suggested that CAI, age, AF, and past TIA were independent risk factors for PSD. The low prevalence of PSD in Chinese patients in comparison with their Caucasian counterparts may be due to the difference in the time frame of the assessment. Comparative studies involving both Caucasian and Chinese stroke patients are required to further explore the role of AF and TIA in the development of PSD in both Chinese and Caucasian patients.

Accuracy of High-resolution Sonography Compared with Magnetic Resonance Imaging in the Diagnosis of Head and Neck Venous Vascular Malformations

AIMS To evaluate whether modern ultrasound examination helps to establish the diagnosis of head and neck venous vascular malformations (VVMs) and whether it can delineate their full extent. MATERIALS AND METHODS Sonographic appearances of 30 head and neck VVMs were assessed for: location, extent, internal architecture, presence of flow and phleboliths. These results were compared with the magnetic resonance imaging (MRI) of the same patients. RESULTS The lesions showed well-defined margins (22 of 30, 73%), heterogeneous (30 of 30, 100%) and hypoechoic echo pattern (27 of 30, 90%), with sinusoidal spaces (28 of 30, 93%) and phleboliths (24 of 30, 80%) on grey-scale imaging, and flow signal on Doppler (28 of 30, 93%). For delineating the extent, ultrasound was comparable with MRI in 53% (16 of 30) and inferior to MRI in 47% (14 of 30). Ultrasound did not detect deeper extent, intra-osseous involvement and other clinically occult VVMs. CONCLUSION Ultrasound with high-resolution transducers can confidently suggest the diagnosis of head and neck VVMs in up to 90% of cases, and delineate the full extent of some superficial lesions. The major disadvantage is its inability to evaluate intra-osseous involvement and the entire extent of large, deep-seated lesions.

Frequency and clinical determinants of poststroke cognitive impairment in nondemented stroke patients.

The objective of this study was to examine the prevalence and clinical correlates of poststroke cognitive impairment in Chinese stroke patients in Hong Kong. One hundred seventy-nine stroke patients were interviewed by a psychiatrist 3 months after their stroke. Cognitive impairment was determined according to the Mini-Mental State Examination score. Thirty-nine participants (21.8%) had cognitive impairment. Univariate analysis found that cognitive impairment was associated with age, female sex, level of education, previous stroke, prestroke Rankin score, National Institutes of Health Stroke Scale dysarthria and total scores, urinary incontinence, and cerebral atrophy index. Multivariate logistic regression suggested that female sex, education, National Institutes of Health Stroke Scale dysarthria score, urinary incontinence, and atrial fibrillation were independent risk factors of poststroke cognitive impairment. After removal of 54 patients with previous stroke from the sample, the frequency of cognitive impairment decreased to 18.4%. It was concluded that cognitive impairment is common among nondemented Chinese stroke patients in Hong Kong.

Neuroimaging determinants of cognitive performances in stroke associated with small vessel disease.

Background and Purpose. Controversies still exist as to the neuroimaging determinants of cognitive impairment in cerebral small vessel disease (SVD). The authors studied the neuroimaging correlates of cognitive performances among patients with stroke associated with SVD. Methods. The authors per formed cerebral computed tomography, magnetic resonance imaging, and diffusion‐weighted imaging among 74 consecu tive patients admitted to the acute stroke unit because of stroke associated with SVD. They examined the association between cognitive performances and the following neuroimaging features: volume of white matter changes (WMC), multiplicity of lacunae, location of lacunae, total cerebral atrophy, and frontal and medial temporal lobe atrophy. Results. Apart from age and education, univariate linear regression analyses revealed that WMC volume, presence of thalamic lacunae, cerebral atrophy, and left frontal lobe atrophy predicted performance on the Mini‐Mental State Examination while WMC volume, presence of thalamic infarcts, cerebral atrophy, and frontal lobe atrophy of both sides predicted performance on the Mattis Dementia Rat ing Scale‐Initiation/Preservation subscale. In the multivariate analyses, education (R2= 0.22, P < .001), left frontal lobe atrophy (R2= 0.10, P= .004), and presence of thalamic lacunae (R2= 0.04, P= .049) were found to predict performance on the Mini‐Mental State Examination while age (R2= 0.23, P < .001) and presence of thalamic lacunae (R2= 0.08, P= .011) were found to predict performance on the Mattis Dementia Rating Scale‐Initiation/Preservation. Conclusions. Among patients with stroke associated with SVD, thalamic lacunae and frontal lobe atrophy are key determinants of cognitive performances.

Determinants of Prestroke Cognitive Impairment in Stroke Associated with Small Vessel Disease

Understanding the determinants of prestroke cognitive impairment (PCI) in stroke associated with small vessel disease (SVD) may shed light on how to prevent further cognitive deterioration after stroke. We administered the Informant Questionnaire on Cognitive Decline (IQCODE) to close informants of 78 consecutive stroke patients who had SVD. PCI, as defined by an average score of IQCODE ≧3.4 was found in 19 (24%) patients. Regression analyses were performed on the following risk factors for PCI: age, years of education, gender, previous stroke, volume of white matter changes, measures of silent lacunes, cerebral atrophy index, medial temporal lobe atrophy and frontal lobe atrophy. Multivariate regression analyses revealed that only cerebral atrophy index (OR 1.5, CI 1.2–1.9, p < 0.001) predicted PCI among patients with SVD.

Impact of Applying NINDS-AIREN Criteria of Probable Vascular Dementia to Clinical and Radiological Characteristics of a Stroke Cohort with Dementia

Background: There are no data concerning the relative representation of clinical vascular risk factors and radiological lesions in cases that have been ruled in and ruled out for probable vascular dementia (VaD) according to NINDS-AIREN criteria. Methods: Three months after their index stroke, a psychiatrist interviewed patients and made a diagnosis of VaD according to both DSM-IV and NINDS-AIREN criteria for probable VaD. Patients who fulfilled the DSM-IV criteria for VaD were divided into two groups: those who were ruled in and ruled out according to NINDS-AIREN criteria as probable VaD. Demographic characteristics, vascular risk factors, clinical features of the index stroke and radiological findings were then compared between the two groups. Results: Of the 297 patients screened, 56 (18.8%) had a DSM-IV diagnosis of dementia. Among these demented patients, 55 (98.2%) and 22 (39.3%) fulfilled DSM-IV and NINDS-AIREN diagnosis of VaD, respectively. The concordance and level of agreement (kappa statistic) between DSM-IV and NINDS-AIREN diagnoses were 40% and 0.02, respectively. Reasons of failure to meet NINDS-AIREN criteria included the lack of temporal relationship between dementia and stroke (n = 20), the absence of focal neurological signs and/or radiological evidence of stroke (n = 6) and both of the above (n = 7). There was no significant difference between the above two groups in terms of demographic data, features of index stroke, vascular risk factors and CT scan findings, except that leukoaraiosis (p = 0.021) and bilateral lesions (p = 0.015) were more frequent in subjects diagnosed according to NINDS-AIREN criteria of probable VaD. The difference between these two groups with respect to the number of lesions was borderline for significance (p = 0.052). Conclusions: The use of NINDS-AIREN criteria for VaD for case selection in poststroke dementia research may exclude a number of subjects with VaD.