Reliability of the global cortical atrophy visual rating scale applied to computed tomography versus magnetic resonance imaging scans in acute stroke

INTRODUCTION

Research using magnetic resonance imaging (MRI) suggests regional cerebral atrophy measures (e.g., frontal lobe, temporal lobe) may predict post-stroke outcomes. Clinical CT scans have excellent potential for use in research but it is unclear whether regional atrophy measures from CT are reliable compared to MRI reference standards.

METHODS

We used the Global Cortical Atrophy (GCA) scale to investigate reliability of atrophy measures on CT versus MRI scans from stroke patients originally recruited to the Oxford Cognitive Screening programme. Two raters provided standardised visual ratings at two timepoints. Weighted Kappa statistics assessed the reliability of regional atrophy scores. Spearman's correlation and a two-way repeated measures ANOVA assessed the reliability of the total score.

RESULTS

On clinically acquired neuroimaging from 98 stroke patients (mean/SD age = 70.97/11.99, 42 female, 84 ischaemic stroke), regional GCA scores on CT versus MRI showed fair to almost perfect intra-rater agreement (κ = .50-.87), substantial to almost perfect intra-rater agreement on CT (κ = .67-.88), and moderate to almost perfect intra-rater reliability on MRI (κ = .50-.89). Regional GCA scores showed mostly moderate to substantial inter-rater reliability on both CT and MRI (κ = .43-.69), except the temporal horns and parieto-occipital region. There was a strong correlation between total GCA scores on CT and MRI (r (96) = .87-.88, p < .001).

CONCLUSIONS

These results support the use of cerebral atrophy measures from CT in clinical research, as visual ratings showed generally good agreement between CT and MRI, between raters, and between timepoints.

Multimodality neuroimaging in vascular mild cognitive impairment: A narrative review of current evidence

The vascular mild cognitive impairment (VaMCI) is generally accepted as the premonition stage of vascular dementia (VaD). However, most studies are focused mainly on VaD as a diagnosis in patients, thus neglecting the VaMCI stage. VaMCI stage, though, is easily diagnosed by vascular injuries and represents a high-risk period for the future decline of patients’ cognitive functions. The existing studies in China and abroad have found that magnetic resonance imaging technology can provide imaging markers related to the occurrence and development of VaMCI, which is an important tool for detecting the changes in microstructure and function of VaMCI patients. Nevertheless, most of the existing studies evaluate the information of a single modal image. Due to the different imaging principles, the data provided by a single modal image are limited. In contrast, multi-modal magnetic resonance imaging research can provide multiple comprehensive data such as tissue anatomy and function. Here, a narrative review of published articles on multimodality neuroimaging in VaMCI diagnosis was conducted，and the utilization of certain neuroimaging bio-markers in clinical applications was narrated. These markers include evaluation of vascular dysfunction before tissue damages and quantification of the extent of network connectivity disruption. We further provide recommendations for early detection, progress, prompt treatment response of VaMCI, as well as optimization of the personalized treatment plan.

Biological and imaging predictors of cognitive impairment after stroke: a systematic review

BACKGROUND

Cognitive impairment is frequent after stroke, and several studies have suggested that biological and imaging characteristics present before stroke are associated with the development of post-stroke cognitive impairment.

OBJECTIVE

The aim of our study was to systematically review biological and imaging predictors of cognitive impairment after stroke.

METHOD

Studies were identified from bibliographic databases and reference lists, and were included if conducted in patients with acute stroke, with at least 30 patients, and a follow-up of at least 3 months. We included articles on potential biomarkers of cognitive impairment that pre-existed to stroke.

RESULTS

We identified 22,169 articles, including 20,349 with abstract. After analysis, 66 studies conducted in 42 cohorts met selection criteria. They included 30-9522 patients [median 170; interquartile range (IQR) 104-251] with a median follow-up of 12 months (IQR 3-36). All studies met quality criteria for description of the study population and standardization of biomarkers. Twenty-nine studies met all quality criteria. There was no convincing evidence that any biological marker may predict cognitive impairment. The most consistent predictors of cognitive impairment after stroke were global atrophy and medial temporal lobe atrophy.

CONCLUSION

Pre-existing cerebral atrophy is the most consistent predictor of cognitive impairment that can be identified in patients with an acute stroke.

Influence of Amyloid-β on Cognitive Decline After Stroke/Transient Ischemic Attack: Three-Year Longitudinal Study

BACKGROUND AND PURPOSE

We hypothesized that comorbid amyloid-beta (Aβ) deposition played a key role in long-term cognitive decline in subjects with stroke/transient ischemic attack.

METHODS

We recruited 72 subjects with cognitive impairment after stroke/transient ischemic attack to receive Carbon-11-labeled Pittsburgh compound B positron emission tomography. We excluded subjects with known clinical Alzheimer's disease. Those with and without Alzheimer's disease-like Aβ deposition were classified as mixed vascular cognitive impairment (mVCI, n=14) and pure VCI (pVCI, n=58), respectively. We performed Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment to evaluate global cognition and cognitive domains (memory, visuospatial function, language, attention, and executive function) at 3 to 6 months (baseline) and annually for 3 years after the index event. We compared cognitive changes between mVCI and pVCI using linear mixed models and analysis of covariance adjusted for age and education.

RESULTS

Over 3 years, there were significant differences between mVCI and pVCI on change of MMSE score over time (group×time interaction, P=0.007). We observed a significant decline on MMSE score (P=0.020) in the mVCI group but not in the pVCI group (P=0.208). The annual rates of decline on MMSE (P=0.023) and Montreal Cognitive Assessment score (P=0.003) were greater in the mVCI group than in the pVCI group. Memory, visuospatial, and executive function domain scores on the Montreal Cognitive Assessment were related to Aβ deposition.

CONCLUSIONS

Compared with subjects without Alzheimer's disease-like Aβ deposition, those with Aβ deposition experienced a more severe and rapid cognitive decline over 3 years after stroke/transient ischemic attack. Aβ was associated with changes in multiple cognitive domains.

The synergistic effect of acupuncture and computer-based cognitive training on post-stroke cognitive dysfunction: a study protocol for a randomized controlled trial of 2 × 2 factorial design

Background

Stroke is one of the most common causes of cognitive impairment. Up to 75% of stroke survivors may be considered to have cognitive impairment, which severely limit individual autonomy for successful reintegration into family, work and social life. The clinical efficacy of acupuncture with Baihui (DU20) and Shenting (DU24) in stroke and post-stroke cognitive impairment has been previously demonstrated. Computer-assisted cognitive training is part of conventional cognitive rehabilitation and has also shown to be effective in improvement of cognitive function of affected patients. However, the cognitive impairment after stroke is so complexity that one single treatment cannot resolve effectively. Besides, the effects of acupuncture and RehaCom cognitive training have not been systematically compared, nor has the possibility of a synergistic effect of combination of the two therapeutic modalities been evaluated. Our primary aim of this trial is to evaluate the synergistic effect of acupuncture and RehaCom cognitive training on cognitive dysfunction after stroke.

Method/Design

A randomized controlled trial of 2 × 2 factorial design will be conducted in the Rehabilitation Hospital Affiliated to Fujian University of Traditional Chinese Medicine. A total of 240 patients with cognitive dysfunction after stroke who meet the eligibility criteria will be recruited and randomized into RehaCom training group, acupuncture group, a combination of both or control group in a 1:1:1:1 ratio. All patients will receive conventional treatment. The interventions will last for 12 weeks (30 min per day, Monday to Friday every week). Evaluations will be conducted by blinded assessors at baseline and again at 4, 8 and 12 weeks. Outcome measurements include mini–mental state examination (MMSE), Montreal cognitive assessments (MoCA), functional independence measure scale (FIM) and adverse events.

Discussion

The results of this trial are expected to clarify the synergistic effect of acupuncture and RehaCom cognitive training on cognitive dysfunction after stroke. Furthermore, to confirm whether combined or alone of acupuncture and RehaCom cognitive training, is more effective than conventional treatment in the management of post-stroke cognitive dysfunction.

Trial registration

Chinese Clinical Trial Registry: ChiCTR-TRC-13003704.

Registration date: 4 September, 2013.

Relationship between poststroke cognition, baseline factors, and functional outcome: data from "efficacy of nitric oxide in stroke" trial

BACKGROUND

Poststroke cognitive impairment is common and identification of prognostic factors associated with it and its relationship with other functional outcomes may help in developing preventative strategies.

METHODS

Previously independent patients with acute stroke, enrolled into the ongoing "Efficacy of Nitric Oxide in Stroke" trial, were assessed by telephone on day 90 for cognitive impairment using modified versions of "Mini Mental State Examination" (MMSE-M) and "Telephone Instrument for Cognitive Status" (TICS-M) scales and category fluency. The relationship of cognitive impairment with baseline prognostic factors and other functional outcomes at day 90 were studied.

RESULTS

The analysis included 1572 patients, mean age 69 years (standard deviation, 12), and female 40%. By 90 days, 246 patients had died, and cognitive impairment was present in 38%. Increasing age, stroke severity, heart rate, and presence of cerebral atrophy on baseline neuroimaging were associated with cognitive impairment (all P < .001). Hypertension and atrial fibrillation were also associated with category fluency and MMSE-M, respectively. Cognition was significantly related to other functional outcomes, TICS-M with dependency (modified Rankin Scale, rs = -.562, P < .001); disability (Barthel Index, rs = .577, P < .001); mood (Zung Depression Score, rs = -.542, P < .001); and quality of life (Euro Quality of life-5 Descriptor, rs = .519, P < .001).

CONCLUSIONS

In previously independent individuals, cognitive impairment was common 3 months after stroke and related to increasing age, stroke severity, hypertension, atrial fibrillation, and cerebral atrophy on brain scanning. Cognition was related to dependency, disability, low mood, and quality of life. Hence, treatment directed toward reducing dependency might also reduce cognitive impairment.

Electroacupuncture ameliorates cognitive impairment through inhibition of NF-κB-mediated neuronal cell apoptosis in cerebral ischemia-reperfusion injured rats

Cognitive impairment is a serious mental deficit following stroke that severely affects the quality of life of stroke survivors. Nuclear factor‑κB (NF-κB)-mediated neuronal cell apoptosis is involved in the development of post-stroke cognitive impairment; therefore, it has become a promising target for the treatment of impaired cognition. Acupuncture at the Baihui (DU20) and Shenting (DU24) acupoints is commonly used in China to clinically treat post‑stroke cognitive impairment; however, the precise mechanism of its action is largely unknown. In the present study, we evaluated the therapeutic efficacy of electroacupuncture against post-stroke cognitive impairment and investigated the underlying molecular mechanisms using a rat model of focal cerebral ischemia-reperfusion (I/R) injury. Electroacupuncture at Baihui and Shenting was identified to significantly ameliorate neurological deficits and reduce cerebral infarct volume. Additionally, electroacupuncture improved learning and memory ability in cerebral I/R injured rats, demonstrating its therapeutic efficacy against post-stroke cognitive impairment. Furthermore, electroacupuncture significantly suppressed the I/R-induced activation of NF-κB signaling in ischemic cerebral tissues. The inhibitory effect of electroacupuncture on NF-κB activation led to the inhibition of cerebral cell apoptosis. Finally, electroacupuncture markedly downregulated the expression of pro-apoptotic Bax and Fas, two critical downstream target genes of the NF-κB pathway. Collectively, our findings suggest that inhibition of NF-κB‑mediated neuronal cell apoptosis may be one mechanism via which electroacupuncture at Baihui and Shenting exerts a therapeutic effect on post-stroke cognitive impairment.

Long-term prognosis of Chinese patients with a lacunar infarct associated with small vessel disease: a five-year longitudinal study

RATIONALE

Lacunar infarct associated with small vessel disease is a common stroke subtype in China and has a favorable short-term prognosis. Data on its long-term prognosis among Chinese patients are lacking.

AIMS

We aimed to study its long-term prognosis and predictors for poor outcomes.

DESIGN

We followed up to 75 consecutive Chinese stroke patients who had a lacunar infarct for a period of 5 years. Clinical outcomes with respect to mortality and recurrent stroke were noted. We evaluated baseline clinical and imaging predictors for such outcomes using the Cox regression analysis.

STUDY OUTCOMES

Sixteen (21.3%) patients died and 12 (16%) patients had recurrent stroke during follow-up. Twenty-one (28%) patients had combined events of either death and/or recurrent stroke. Univariate Cox regression analysis showed that age, literacy, National Institute of Health Stroke Scale, incident stroke/transient ischemic attack, and white matter lesion volume predicted survival, while, age, National Institute of Health Stroke Scale, systolic blood pressure, hyperhomocysteinemia, silent lacunes, microbleeds, and white matter lesion volume predicted recurrent stroke. Multivariate Cox regression analysis showed that National Institute of Health Stroke Scale (HR 1.25, 95% CI 1.05-1.48) and white matter lesion volume (HR 1.46, 95% CI 1.11-1.92) predicted combined events of mortality and/or recurrent stroke after age adjustment.

CONCLUSION

Approximately one in four patients either died and/or had recurrent stroke within 5 years after a lacunar infarct. Age, stroke severity, and volume of white matter lesion predict a poor long-term prognosis.

Comparing Mattis Dementia Rating Scale--initiation/perseveration subset and frontal assessment battery in stroke associated with small vessel disease

Forty-two controls and 32 patients with stroke associated with small vessel disease (SSVD) were administered the Mattis Dementia Rating Scale Initiation / Perseveration subset (MDRS I/P) and Frontal Assessment Battery (FAB). Both tests showed comparably good ability in Receiver Operating Characteristics curves analysis (AUCMDRS I/P=0.887; AUC FAB=0.854, p=.833) in discriminating between controls and patients and correctly classified over 78% of subjects. Verbal fluency and motor programming contributed most to the discriminating power in the two tests. The MDRS I/P and FAB are useful in discriminating between controls and SSVD patients in a hospital setting.

Mild cognitive impairment after lacunar infarction: voxel-based morphometry and neuropsychological assessment

BACKGROUND

The aim of the present study was to investigate whether there were differences in neuroradiological features, including white-matter lesions and gray-matter volumes, between patients with lacunar infarction with and without mild cognitive impairment of the vascular type (MCI-V).

METHODS

A total of 40 patients with lacunar infarction were studied within 1 month after stroke.

RESULTS

MCI-V was found in 22 patients, who in comparison with patients without cognitive impairment were significantly older and had fewer years of formal education. MRI subcortical hyperintensities especially in the basal ganglia (putamen and thalamus) were significantly more frequent in the MCI-V group. In the voxel-based morphometric study, patients with MCI-V showed more atrophy bilaterally in the middle temporal gyrus, right and left frontal and posterior bilateral occipitoparietal regions including the posterior cingulate as well as in the cerebellum. A region of interest analysis restricted to the parahippocampi and hippocampi showed further reduced bilateral parahippocampal gyrus and right hippocampus volume reductions in this group of patients. Finally, the amount of white-matter lesions among MCI-V showed negative correlations with gray-matter volume in frontal and temporal areas as well as with the thalamus and mesencephalon.

CONCLUSIONS

The present findings provide support for an anatomical substrate of the MCI entity in patients with lacunar infarction. Both gray- and white-matter changes seem to contribute to the cognitive impairment of such patients.

Hyperhomocysteinemia is associated with volumetric white matter change in patients with small vessel disease

BACKGROUND

Hyperhomocysteinemia is associated with cerebral small vessel disease (SVD). We examined the relationship between homocysteine and 1) volumetric measure of white matter change (WMC), 2) silent brain infarcts, 3) cerebral atrophy on MRI and 4) cognition on a consecutive cohort of patients with stroke associated with SVD.

SUBJECTS AND METHODS

Fifty-seven patients consecutively admitted to the Acute Stroke Unit in a university hospital due to stroke associated with SVD were recruited and assessed three months after the stroke. Non-fasting homocysteine was obtained. Using MRI, the number of infarcts, volume of WMC and cerebral atrophy were measured. General cognitive functions were assessed using the Mini Mental State Examination and Alzheimer's disease Assessment Scale. Mattis Dementia Rating Scale - Initiation/Perseveration subset was used to assess executive cognitive functions.

RESULTS

Hyperhomocysteinemia (> or = 14.88 micromol/L) significantly accounted for the volume of WMC on MRI in a multivariate stepwise regression model (adjusted R(2)=0.058, p <0.05) after adjustment for age and folate level. Patients in the highest quartile of WMC volume had significantly higher levels of homocysteine than those in lowest quartile (p <0.001). No significant relationship was found between homocysteine and silent brain infarcts, cerebral atrophy and performance on psychometric tests.

CONCLUSION

Hyperhomocysteinemia is associated with volumetric measure of WMC among patients with SVD. The role of homocysteine in the development of silent brain infarcts and cerebral atrophy as previously reported cannot be ascertained in this study. No direct relationship was found between homocysteine and cognitive functions.