Refinement of Imaging Predictors of Recurrent Events following Transient Ischemic Attack and Minor Stroke

Background

TIA and minor stroke have a high risk of recurrent stroke. Abnormalities on CT/CTA and MRI predict recurrent events in TIA and minor stroke. However there are many other imaging abnormalities that could potentially predict outcome that have not been assessed in this population. Also the definition of recurrent events used includes deterioration due to stroke progression or recurrent stroke and whether imaging is either of these is not known.

Aims

To improve upon the clinical, CT/CTA and MRI parameters that predict recurrent events after TIA and minor stroke by assessing further imaging parameters. Secondary aim was to explore predictors of stroke progression versus recurrent stroke.

Methods

510 consecutive TIA and minor stroke patients had CT/CTA and most had MRI. Primary outcome was recurrent events (stroke progression or recurrent stroke) within 90 days. Further imaging parameters were assessed for prediction of recurrent events (combined outcome of stroke progression and recurrent stroke). We also explored predictors of symptom progression versus recurrence individually.

Results

36 recurrent events (36/510, 7.1% (95% CI: 5.0–9.6)) including 19 progression and 17 recurrent strokes. On CT/CTA: white matter disease, prior stroke, aortic arch focal plaque≥4 mm, or intraluminal thrombus did not predict recurrent events (progression or recurrent stroke). On MRI: white matter disease, prior stroke, and microbleeds did not predict recurrent events. Parameters predicting the individual outcome of symptom progression included: ongoing symptoms at initial assessment, symptom fluctuation, intracranial occlusion, intracranial occlusion or stenosis, and the CT/CTA metric. No parameter was strongly predictive of a distinct recurrent stroke.

Conclusions

There was no imaging parameter that could improve upon our original CT/CTA or MRI metrics to predict the combined outcome of stroke progression or a recurrent stroke after TIA and minor stroke. We are better at using imaging to predict stroke progression rather than recurrent stroke.     

Aberrant Functional Connectivity of Resting State Networks in Transient Ischemic Attack

Background

Transient ischemic attack (TIA) is usually defined as a neurologic ischemic disorder without permanent cerebral infarction. Studies have showed that patients with TIA can have lasting cognitive functional impairment. Inherent brain activity in the resting state is spatially organized in a set of specific coherent patterns named resting state networks (RSNs), which epitomize the functional architecture of memory, language, attention, visual, auditory and somato-motor networks. Here, we aimed to detect differences in RSNs between TIA patients and healthy controls (HCs).

Methods

Twenty one TIA patients suffered an ischemic event and 21 matched HCs were enrolled in the study. All subjects were investigated using cognitive tests, psychiatric tests and functional magnetic resonance imaging (fMRI). Independent component analysis (ICA) was adopted to acquire the eight brain RSNs. Then one-sample t-tests were calculated in each group to gather the spatial maps of each RSNs, followed by second level analysis to investigate statistical differences on RSNs between twenty one TIA patients and 21 controls. Furthermore, a correlation analysis was performed to explore the relationship between functional connectivity (FC) and cognitive and psychiatric scales in TIA group.

Results

Compared with the controls, TIA patients exhibited both decreased and increased functional connectivity in default mode network (DMN) and self-referential network (SRN), and decreased functional connectivity in dorsal attention network (DAN), central-executive network (CEN), core network (CN), somato-motor network (SMN), visual network (VN) and auditory network (AN). There was no correlation between neuropsychological scores and functional connectivity in regions of RSNs.

Conclusions

We observed selective impairments of RSN intrinsic FC in TIA patients, whose all eight RSNs had aberrant functional connectivity. These changes indicate that TIA is a disease with widely abnormal brain networks. Our results might put forward a novel way to look into neuro-pathophysiological mechanisms in TIA patients.     

短暂性脑缺血发作患者血脂水平与ABCD2评分的相关性研究

目的：探讨短暂性脑缺血发作（transient ischemia attach,TIA）患者血脂水平对预后的影响及其临床意义。方法：回顾性分析以2009年最新定义为诊断标准的我院TIA患者62例,根据ABCD2评分进行危险分级。其中,低危组（0--3分）患者16例、中危组（4～5分）患者20例,高危组（6～7分）患者26例,比较三组患者血脂水平的差异及其预后效果的影响。结果：三组患者中血脂水平从高到低依次为：高危组、中危组与低危组,其中高危组血脂水平与其它两组患者血脂水平的差异均有统计学意义（P〈0．05）,但中危组与低危组间差异无统计学意义（P〉0．05）。低、中危组患者血脂平均水平随ABCD2分值增高呈轻度上升趋势,高危组患者血脂平均水平随ABCD2分值明显增高。血脂水平越高其预后效果相对越差。结论：血脂水平与TIA患者ABCD2评分呈正相关的趋势,而与预后效果呈负相关的趋势。     

短暂性脑缺血发作患者血脂水平与ABCD2 评分的相关性研究

目的:探讨短暂性脑缺血发作(transient ischemia attach,TIA)患者血脂水平对预后的影响及其临床意义。方法:回顾性分析以2009年最新定义为诊断标准的我院TIA患者62例,根据ABCD2评分进行危险分级。其中,低危组(0～3分)患者16例、中危组(4～5分)患者20例,高危组(6～7分)患者26例,比较三组患者血脂水平的差异及其预后效果的影响。结果:三组患者中血脂水平从高到低依次为:高危组、中危组与低危组,其中高危组血脂水平与其它两组患者血脂水平的差异均有统计学意义(P<0.05),但中危组与低危组间差异无统计学意义(P>0.05)。低、中危组患者血脂平均水平随ABCD2分值增高呈轻度上升趋势,高危组患者血脂平均水平随ABCD2分值明显增高。血脂水平越高其预后效果相对越差。结论:血脂水平与TIA患者ABCD2评分呈正相关的趋势,而与预后效果呈负相关的趋势。     

丁苯酞软胶囊联合奥扎格雷钠治疗短暂性脑缺血发作的临床观察

目的:探讨丁苯酞软胶囊联合奥扎格雷钠在短暂性脑缺血发作(TIA)病情治疗中的临床效果.方法:选取住院确诊为TIA患者60例,随机分为用药组和对照组,每组30例,对照组使用奥扎格雷钠治疗,用药组使用丁苯酞软胶囊和奥扎格雷钠联合治疗.观察两组的临床疗效.结果:用药组的终止发作时间短于对照组(P＜0.05).治疗后纤维蛋白原含量和甘油三酯含量与治疗前相比较,两种的变化差异均有统计学意义(P＜0.05),但两组治疗后纤维蛋白原含量和甘油三酯含量的分布上差异均有统计学意义(P＜0.05),用药组的治疗效果要明显优于对照组.两组3个月、6个月及9个月TIA复发率及卒中发生率差异有统计学意义(P＜0.05).结论:丁苯酞软胶囊与奥扎格雷钠联用治疗TIA安全有效,复发率及脑卒中的发生率低,值得临床广泛应用.     

Acute Endovascular Reperfusion Therapy in Ischemic Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Randomized controlled trials (RCTs) of endovascular therapy for acute ischemic stroke have had inconsistent results. We evaluated the efficacy and safety of endovascular therapy in published RCTs.

Methods

We performed a systematic review of RCTs of endovascular therapy with thrombolytic or mechanical reperfusion compared with interventions without endovascular therapy. Primary outcome was the frequency of good functional outcome (modified Rankin scale (mRS) of 0-2 at 90 days) and secondary outcomes were mortality at 90 days and symptomatic intracranial hemorrhage (sICH). Random-effects meta-analysis was performed and the Cochrane risk of bias assessment was used to evaluate quality of evidence.

Results

Ten studies involving 1,612 subjects were included. Endovascular therapy was not significantly associated with good functional outcome (Relative Risk [RR] =1.17; 95% CI, 0.97 to 1.42; p=0.10 and Absolute Risk Difference [ARD] =7%; 95%CI -0.1% to 14%; p=0.05); heterogeneity was moderate among studies (I²=30%). Mortality was unchanged with endovascular therapy (RR=0.92; 95 % CI, 0.75 to 1.13; p=0.45) and there was no difference in sICH (RR=1.20; 95 % CI, 0.79 to 1.82; p=0.39). The quality of evidence was low for all outcomes and the recommendation is weak for the use of endovascular therapy as per GRADE methodology.

Conclusions

Intra-arterial therapy did not show significant increase in good outcomes and no changes in either mortality or sICH in patients with acute ischemic stroke. We need further RCTs with better design and quality to evaluate the true efficacy of endovascular therapy.     

Preliminary Investigation: Acupoint-Skin Conductance in Stroke Survivors

It has been reported that patients with rheumatoid arthritis or asthma have skin conductance over the acupoints that is lower than that of their healthy counterparts; this has been regarded as indirect evidence of the existence of acupoints and the energy-based model of diseases. In order to investigate the potential application of acupoint-skin conductance measurement that may reflect pathology of ischemic stroke, the present study recruited 34 stroke survivors with hemiparesis, whose skin conductance of a hand acupoint and an adjacent non-acupoint and the finger temperature in both affected and unaffected hands were simultaneously measured; the data revealed that the skin conductance and finger temperature were statistically higher in the unaffected hand than that of the affected, and the skin conductance of the acupoint and the non-acupoint were comparable in the affected and unaffected hands respectively. We attribute the observed drop in the skin conductance to the diminished peripheral blood flow of the affected hand that is signified by relatively lower finger temperature. As such, it should be advisable when studying skin conductance over acupoints, monitoring the adjacent non-acupoint skin and local vascular circulation is essential.     

Prevalence,Incidence, and Mortality of Stroke in the Chinese Island Populations: A Systematic Review

Background

In China, there are 2.5 million new stroke cases each year and 7.5 million stroke survivors. However, stroke incidence in some island populations is obviously lower compared with inland regions, perhaps due to differences in diet and lifestyle. As the lifestyle in China has changed significantly, along with dramatic transformations in social, economic and environmental conditions, such changes have also been seen in island regions. Thus, we analyzed stroke in the Chinese island regions over the past 30 years.

Methods

We conducted a systematic review to identify reliable and comparable epidemiologic evidence about stroke in the Chinese island regions between 1980 and 2013. Two authors independently assessed the eligibility and the quality of the articles and disagreement was resolved by discussion. Owing to the great heterogeneity among individual study estimates, a random-effects or fixed-effects model was used to incorporate the heterogeneity among records into a pooled estimate for age-standardized rates. Age-standardized rates were calculated by the direct method with the 2000 world population if included records provided the necessary information.

Results

During the past three decades, the overall pooled age-standardized prevalence of stroke is 6.17 per 1000 (95% CI 4.56–7.78), an increase from 5.54 per 1000 (95% CI 3.88–7.20) prior to 2000 to 8.34 per 1000 (95% CI 5.98–10.69) after 2000. However, this difference was not found to be statistically significant. The overall pooled age-standardized incidence of stroke is 120.42 per 100,000 person years (95% CI 26.17–214.67). Between 1982 and 2008, the incidence of stroke increased and mortality declined over time.

Conclusions

Effective intervention and specific policy recommendations on stroke prevention should be required, and formulated in a timely fashion to effectively curb the increased trend of stroke in Chinese island regions.     

临床路径对短暂性脑缺血患者影响的ITS分析

目的 了解某医院实施临床路径改革对短暂性脑缺血发作（transient ischemic attack,TIA）患者药费、检查费和住院日的影响。方法 使用间断时间序列分析方法（ITS）分析方法对医院2012年12月至2015年5月TIA患者药费、检查费和住院日进行分析。结果 检查费、住院日显著性下降,药费下降但无统计学意义。结论 实施临床路径改革对缩短患者住院日和控制医疗费用具有积极作用。     

A Systematic Review of PTSD Prevalence and Trajectories in DSM-5 Defined Trauma Exposed Populations: Intentional and Non-Intentional Traumatic Events

Objective

We conducted a systematic review of the literature to explore the longitudinal course of PTSD in DSM-5-defined trauma exposed populations to identify the course of illness and recovery for individuals and populations experiencing PTSD.

Methods

We reviewed the published literature from January 1, 1998 to December 31, 2010 for longitudinal studies of directly exposed trauma populations in order to: (1) review rates of PTSD in the first year after a traumatic event; (2) examine potential types of proposed DSM-5 direct trauma exposure (intentional and non-intentional); and (3) identify the clinical course of PTSD (early onset, later onset, chronicity, remission, and resilience). Of the 2537 identified articles, 58 articles representing 35 unique subject populations met the proposed DSM-5 criteria for experiencing a traumatic event, and assessed PTSD at two or more time points within 12 months of the traumatic event.

Results

The mean prevalence of PTSD across all studies decreases from 28.8% (range  = 3.1–87.5%) at 1 month to 17.0% (range  = 0.6–43.8%) at 12 months. However, when traumatic events are classified into intentional and non-intentional, the median prevalences trend down for the non-intentional trauma exposed populations, while the median prevalences in the intentional trauma category steadily increase from 11.8% to 23.3%. Across five studies with sufficient data, 37.1% of those exposed to intentional trauma develop PTSD. Among those with PTSD, about one third (34.8%) remit after 3 months. Nearly 40% of those with PTSD (39.1%) have a chronic course, and only a very small fraction (3.5%) of new PTSD cases appears after three months.

Conclusions

Understanding the trajectories of PTSD over time, and how it may vary by type of traumatic event (intentional vs. non-intentional) will assist public health planning and treatment.     

Dietary Habits in Patients with Ischemic Stroke: A Case-Control Study

Background and Aims

Diet appears to have some role in stroke development. The objective of our study was to describe the dietary habits in patients admitted with acute ischemic stroke and compare selected dietary components with healthy controls. Adherence to healthy diet behaviors was also assessed.

Methods

A case-control study of consecutive patients with acute ischemic stroke admitted to the Neurology Department of Hospital del Mar from 2007 to 2010. Patients were matched by age and sex with control subjects. A previously validated nutritional survey was administered to patients and controls. Demographic data, vascular risk factors, caloric intake and dietary nutrients were evaluated. Intention to follow a healthy diet was also assessed in both groups.

Results

A total of 300 acute ischemic stroke patients and 300 controls with evaluation of dietary habits. No differences were observed in vascular risk factors, except smoking habit, diabetes and ischemic heart disease. Stroke patients reported a higher caloric intake: 2444.8(1736.8–3244.5) vs 2208.7(1753.1–2860.7) Kcal, p = 0.001. After adjusting for energy intake, patients had higher intake of proteins (p<0.001; OR 1.02), total cholesterol (p = 0.001; OR 1.04), and breaded foods (p = 0.001; OR 1.94) and lower consumption of probiotic yogurt (p = 0.002; OR 0.88). Compared to patients, control participants indicated greater intention to eat vegetables (p = 0.002; OR 1.5) and whole foods (p = 0.000; OR 2.4) and reduce their intake of salt (p = 0.002; OR 1.7), fat (p = 0.000; OR 3.7) and sweets (p = 0.004; OR 1.7) than patients.

Conclusion

We observed different dietary patterns between stroke patients and controls. Stroke patients have a higher caloric intake and are less concerned about maintaining healthy nutritional habits.     

Association between Ischemic Stroke and Iron-Deficiency Anemia: A Population-Based Study

Background

Very little is known about the relationship between non-sickle cell anemia and stroke. The purpose of this study is to evaluate the association of iron-deficiency anemia (IDA) with stroke based on a nationwide coverage database in Taiwan.

Methods

The case-control study subjects were obtained from the Taiwanese Longitudinal Health Insurance Database 2000. We included 51,093 subjects with stroke as cases and randomly selected 153,279 controls (3 controls per case) in this study.Separate conditional logistic regression analyses were used to calculate the odds ratio (OR) for having been previously diagnosed with IDA between cases and controls.We further analyzed the association between stroke and IDA by stroke subtype.

Results

Results showed that 3,685 study subjects (1.81%) had been diagnosed with IDA prior to the index date; of those subjects, 1,268 (2.48%) were cases and 2,417 (1.58%) were controls (p<0.001). Conditional logistic regression shows that the OR of having previously received an IDA diagnosis among cases was 1.49 (95% CI: 1.39~1.60; p < 0.01) that of controls after adjusting for monthly income, geographic region, hypertension, diabetes, coronary heart disease, atrial fibrillation, heart failure, hyperlipidemia, tobacco use disorder, and alcohol abuse/alcohol dependency syndrome. Furthermore, the adjusted OR of prior IDA for cases with ischemic stroke was found to be 1.45 (95% CI: 1.34~1.58) compared to controls. However, we did not find any significant relationship between IDA and subarachnoid/intracerebral hemorrhage even adjusting for other confounding factors (OR=1.17, 95% CI=0.97~1.40).

Conclusion

There is a significant association between prior IDA and ischemic stroke.     

磁共振弥散加权成像在检测短暂性脑缺血责任病灶的临床价值

目的:探讨磁共振弥散加权成像显示短暂性脑缺血责任病灶的敏感性及其临床应用价值.方法:对连续的39例资料完整的住院TIA患者进行了常规磁共振成像和弥散加权磁共振成像(diffusion-weighted MRI,DWI)检查,对比不同成像序列对短暂性脑缺血责任病灶的检出率.结果:在39例TIA患者中,快速自旋回波序列(FSET1WI和FSET2WI)检出TIA责任病灶9例(9/39);翻转恢复序列(FLAIR)检出11例(11/39);弥散加权序列检出15例(15/39).不同序列检出率比较运用单因素的方差分析显示有明显差异(P=0.001),弥散加权序列检出率最高.结论:DWI序列对TIA责任病灶的检出率明显高于常规MR,可为TIA患者的临床处理提供可靠诊断信息.     

Nurse-Led,Telephone-Based,Secondary Preventive Follow-Up after Stroke or Transient Ischemic Attack Improves Blood Pressure and LDL Cholesterol: Results from the First 12 Months of the Randomized,Controlled NAILED Stroke Risk Factor Trial

Background

Enhanced secondary preventive follow-up after stroke or transient ischemic attack (TIA) is necessary for improved adherence to recommendations regarding blood pressure (BP) and low-density lipoprotein cholesterol (LDL-C) levels. We investigated whether nurse-led, telephone-based follow-up was more efficient than usual care at improving BP and LDL-C levels at 12 months after hospital discharge.

Methods

We randomized 537 patients to either nurse-led, telephone-based follow-up (intervention) or usual care (control). BP and LDL-C measurements were performed at 1 month (baseline) and 12 months post-discharge. Intervention group patients who did not meet target values at baseline received additional follow-up, including titration of medication and lifestyle counselling, to reach treatment goals (BP < 140/90 mmHg, LDL-C < 2.5 mmol/L).

Results

At 12 months, mean systolic BP, diastolic BP and LDL-C was 3.3 (95% CI 0.3 to 6.3) mmHg, 2.3 mmHg (95% CI 0.5 to 4.2) and 0.3 mmol/L (95% CI 0.1 to 0.4) lower in the intervention group compared to controls. Among participants with values above the treatment goal at baseline, the difference in systolic BP and LDL-C was more pronounced (8.0 mmHg, 95% CI 4.0 to 12.1, and 0.6 mmol/L, 95% CI 0.4 to 0.9). A larger proportion of the intervention group reached the treatment goal for systolic BP (68.5 vs. 56.8%, p = 0.008) and LDL-C (69.7% vs. 50.4%, p < 0.001).

Conclusions

Nurse-led, telephone-based secondary preventive follow-up, including medication adjustment, was significantly more efficient than usual care at improving BP and LDL-C levels by 12 months post-discharge.

Trial Registration

ISRCTN Registry ISRCTN23868518     

A Meta-Analytic Review of Stand-Alone Interventions to Improve Body Image

Objective

Numerous stand-alone interventions to improve body image have been developed. The present review used meta-analysis to estimate the effectiveness of such interventions, and to identify the specific change techniques that lead to improvement in body image.

Methods

The inclusion criteria were that (a) the intervention was stand-alone (i.e., solely focused on improving body image), (b) a control group was used, (c) participants were randomly assigned to conditions, and (d) at least one pretest and one posttest measure of body image was taken. Effect sizes were meta-analysed and moderator analyses were conducted. A taxonomy of 48 change techniques used in interventions targeted at body image was developed; all interventions were coded using this taxonomy.

Results

The literature search identified 62 tests of interventions (N = 3,846). Interventions produced a small-to-medium improvement in body image (d ₊ = 0.38), a small-to-medium reduction in beauty ideal internalisation (d ₊ = -0.37), and a large reduction in social comparison tendencies (d ₊ = -0.72). However, the effect size for body image was inflated by bias both within and across studies, and was reliable but of small magnitude once corrections for bias were applied. Effect sizes for the other outcomes were no longer reliable once corrections for bias were applied. Several features of the sample, intervention, and methodology moderated intervention effects. Twelve change techniques were associated with improvements in body image, and three techniques were contra-indicated.

Conclusions

The findings show that interventions engender only small improvements in body image, and underline the need for large-scale, high-quality trials in this area. The review identifies effective techniques that could be deployed in future interventions.     

Classifiers for Ischemic Stroke Lesion Segmentation: A Comparison Study

Motivation

Ischemic stroke, triggered by an obstruction in the cerebral blood supply, leads to infarction of the affected brain tissue. An accurate and reproducible automatic segmentation is of high interest, since the lesion volume is an important end-point for clinical trials. However, various factors, such as the high variance in lesion shape, location and appearance, render it a difficult task.

Methods

In this article, nine classification methods (e.g. Generalized Linear Models, Random Decision Forests and Convolutional Neural Networks) are evaluated and compared with each other using 37 multiparametric MRI datasets of ischemic stroke patients in the sub-acute phase in terms of their accuracy and reliability for ischemic stroke lesion segmentation. Within this context, a multi-spectral classification approach is compared against mono-spectral classification performance using only FLAIR MRI datasets and two sets of expert segmentations are used for inter-observer agreement evaluation.

Results and Conclusion

The results of this study reveal that high-level machine learning methods lead to significantly better segmentation results compared to the rather simple classification methods, pointing towards a difficult non-linear problem. The overall best segmentation results were achieved by a Random Decision Forest and a Convolutional Neural Networks classification approach, even outperforming all previously published results. However, none of the methods tested in this work are capable of achieving results in the range of the human observer agreement and the automatic ischemic stroke lesion segmentation remains a complicated problem that needs to be explored in more detail to improve the segmentation results.     

Rodent Gymnastics: Neurobehavioral Assays in Ischemic Stroke

Despite years of research, most preclinical trials on ischemic stroke have remained unsuccessful owing to poor methodological and statistical standards leading to “translational roadblocks.” Various behavioral tests have been established to evaluate traits such as sensorimotor function, cognitive and social interactions, and anxiety-like and depression-like behavior. A test’s validity is of cardinal importance as it influences the chance of a successful translation of preclinical results to clinical settings. The mission of choosing a behavioral test for a particular project is, therefore, imperative and the present review aims to provide a structured way to evaluate rodent behavioral tests with implications in ischemic stroke.