ABCD2 score and secondary stroke prevention: meta-analysis and effect per 1,000 patients triaged

Corneal nerve and endothelial cell damage in patients with transient ischemic attack and minor ischemic stroke

OBJECTIVE

To determine if corneal confocal microscopy can identify corneal nerve and endothelial cell abnormalities and may be useful in the prognostication of patients with transient ischemic attack [1] or minor ischemic stroke (IS).

METHODS

Thirty-six patients admitted with TIA (n = 14) or minor IS (n = 22) underwent transcranial Doppler evaluation and corneal confocal microscopy and were compared with 18 healthy controls.

RESULTS

Corneal nerve fiber density (P = 0.002), branch density (P = 0.004) and fiber length (P = 0.004) were significantly lower in patients with TIA or minor IS compared to controls, with no difference between patients with TIA and minor IS. Endothelial cell density (P = 0.003) was lower and endothelial cell area (P = 0.003) and perimeter (P = 0.006) were significantly higher in patients with TIA or minor IS compared to controls, with no difference between patients with TIA and minor IS. There were no differences in corneal nerve or endothelial cell morphology between patients with and without abnormal cerebrovascular reactivity. HbA1c was independently associated with CNFL, and endothelial cell polymegathism and pleomorphism were associated with both HbA1c and total cholesterol.

CONCLUSION

Corneal confocal microscopy identifies corneal nerve fiber loss and endothelial cell abnormalities in patients with TIA and minor IS and independent associations with HbA1c and cholesterol.

Early Identification of High-Risk TIA or Minor Stroke Using Artificial Neural Network

Background and Purpose: The risk of recurrent stroke following a transient ischemic attack (TIA) or minor stroke is high, despite of a significant reduction in the past decade. In this study, we investigated the feasibility of using artificial neural network (ANN) for risk stratification of TIA or minor stroke patients.

Methods: Consecutive patients with acute TIA or minor ischemic stroke presenting at a tertiary hospital during a 2-year period were recruited. We collected demographics, clinical and imaging data at baseline. The primary outcome was recurrent ischemic stroke within 1 year. We developed ANN models to predict the primary outcome. We randomly down-sampled patients without a primary outcome to 1:1 match with those with a primary outcome to mitigate data imbalance. We used a 5-fold cross-validation approach to train and test the ANN models to avoid overfitting. We employed 19 independent variables at baseline as the input neurons in the ANN models, using a learning algorithm based on backpropagation to minimize the loss function. We obtained the sensitivity, specificity, accuracy and the c statistic of each ANN model from the 5 rounds of cross-validation and compared that of support vector machine (SVM) and Naïve Bayes classifier in risk stratification of the patients.

Results: A total of 451 acute TIA or minor stroke patients were enrolled. Forty (8.9%) patients had a recurrent ischemic stroke within 1 year. Another 40 patients were randomly selected from those with no recurrent stroke, so that data from 80 patients in total were used for 5 rounds of training and testing of ANN models. The median sensitivity, specificity, accuracy and c statistic of the ANN models to predict recurrent stroke at 1 year was 75%, 75%, 75%, and 0.77, respectively. ANN model outperformed SVM and Naïve Bayes classifier in our dataset for predicting relapse after TIA or minor stroke.

Conclusion: This pilot study indicated that ANN may yield a novel and effective method in risk stratification of TIA and minor stroke. Further studies are warranted for verification and improvement of the current ANN model.

Transient ischemic attack: Incidence and early risk of stroke in northern Portugal from 1998–2000 to 2009–2011

Objective

A decline in TIA incidence would be expected mirroring stroke trends, but patient's awareness of symptoms/signs, improved diagnostic procedures and changes in severity of vascular disease may raise TIA incidence. We aimed to estimate changes in TIA incidence and 30-day stroke risk in Portugal.

Methods

Data from two prospective community-based registers of first-ever TIA in 104,700 (1998–2000) and 118,232 (2009–2011) persons were collected using comprehensive case ascertainment methods. Incidence and stroke risk from TIA onset were compared using different inception cohorts. ABCD2 was used to stratified stroke risk.

Results

Overall, 141 patients were included in 1998–2000 and 174 in 2009–2011. Crude annual incidence rate increased from 67 to 74/100,000 (IRR=1.12; 95% CI, 0.90–1.40), particularly in men under 65 years (IRR=1.79; 95% CI, 1.06–3.04). Male/female IRR increased from 1.20 (0.86–1.68) in 1998–2000 to 1.77 (1.31–2.39) in 2009–2011, after adjustment for age. Better control of vascular risk factors (VRFs) accounted for lower ABCD2 scores in 2009–2011. The 30-day stroke risk was similar in study periods (18.4% vs. 16.7%, p > 0.7), decreasing from 16.1% to 8.2% ( p < 0.042) excluding patients reporting TIA after stroke occurrence and from 12.2% to 4.0% ( p < 0.011) further excluding patients who had stroke in ambulance/hospital. ABCD2 discriminated stroke risk only in 1998–2000; stroke severity decreased while posterior circulation stroke was more common in 2009–2011.

Conclusion

Despite a stable TIA incidence across periods, the risk increased in men compared to women. Better control of VRF accounted for lower ABCD2 scores and secondary prevention reduced stroke risk. Men under 65 years emerge as a preferential target for primary and secondary prevention.

Stroke risk after transient ischemic attack in a Norwegian prospective cohort

BACKGROUND

Transient ischemic attack (TIA) is a risk factor of stroke. Modern treatment regimens and changing risk factors in the population justify new estimates of stroke risk after TIA, and evaluation of the recommended ABCD² stroke risk score.

METHODS

From October, 2012, to July, 2014, we performed a prospective, multicenter study in Central Norway, enrolling patients with a TIA within the previous 2 weeks. Our aim was to assess stroke risk at 1 week, 3 months and 1 year after TIA, and to determine the predictive value of the dichotomized ABCD² score (0-3 vs 4-7) at each time point. We used data obtained by telephone follow-up and registry data from the Norwegian Stroke Register.

RESULTS

Five hundred and seventy-seven patients with TIA were enrolled of which 85% were examined by a stroke specialist within 24 h after symptom onset. The cumulative incidence of stroke within 1 week, 3 months and 1 year of TIA was 0.9% (95% CI, 0.37-2.0), 3.3% (95% CI, 2.1-5.1) and 5.4% (95% CI, 3.9-7.6), respectively. The accuracy of the ABCD² score provided by c-statistics at 7 days, 3 months and 1 year was 0.62 (95% CI, 0.39-0.85), 0.62 (95% CI, 0.51-0.74) and 0.64 (95% CI, 0.54-0.75), respectively.

CONCLUSIONS

We found a lower stroke risk after TIA than reported in earlier studies. The ABCD² score did not reliably discriminate between low and high risk patients, suggesting that it may be less useful in populations with a low risk of stroke after TIA.

TRIAL REGISTRATION

Unique identifier: NCT02038725 (retrospectively registered, January 16, 2014).

Predictive Value of A2HD Scoring for Transient Symptoms Associated with Infarction

Background

Effective early management of cerebral infarction patients with transient ischemic attack (TIA) is undermined by an inability to predict who is at highest risk of stroke.

Material/Methods

A total of 577 TIA patients with symptoms lasting no more than 1 hour were prospectively investigated and divided into a TIA group and a transient symptoms associated with infarction (TSI) group based on diffusion-weighted magnetic resonance imaging findings after hospital admission. The baseline characteristics, symptoms of TIA, features of disease onset, and findings from clinical examinations were compared between the 2 groups. Factors related to TSI were further analyzed.

Results

Of 577 TIA patients, 127 patients were in the TSI group and 450 were in the TIA group. Anterior circulation events, hemiplegia, aphasia, multiple seizures, maximal duration, atrial fibrillation, and hypointense plaques were included as risk factors for stroke in a model of multivariate analysis, and results showed that hemiplegia, aphasia, multiple seizures, and atrial fibrillation were independent risk factors for TSI. In the final mode, the area under the curve (AUC) was 0.766 (95% confidence interval: 0.729–0.800). According to the A2HD score and odds ratio, hemiplegia (score 2), aphasia (score 2), multiple seizures (score 2), and atrial fibrillation (score 1) were scored, and any increment in the score increased the risk for cerebral infarction by 1.893-fold (95% confidence interval: 1.643–2.181).

Conclusions

Risk of TSI seems to be highly predictable. The A2HD score can be used in clinical practice to identify high-risk cerebral infarction patients with TIA who need emergency diagnosis and treatment.

Predictive Value of Head-Neck CTA Combined with ABCD2 Scale Score for Patients with Cerebral Infarction of Vertebrobasilar Transient Ischemic Attack (TIA)

Background

The present study was designed to evaluate the predictive value of head-neck computed tomography angiography (CTA) combined with ABCD2 score scale for patients with cerebral infarction of vertebrobasilar transient ischemic attack (TIA).

Material/Methods

A total of 92 patients with TIA who were admitted to our hospital from January 2014 to June 2015 were enrolled in this study. ABCD2 score and CTA combined with ABCD2 score were assessed.

Results

The incidence of cerebral infarction was highest in the high-risk group, followed by the middle-risk group and low-risk group. The incidence of cerebral infarction was related to the degree of stenosis in head-neck CTA, which was highest in the severe stenosis group, followed by the moderate stenosis group and mild stenosis/normal group, with significant differences. The incidence of cerebral infarction in patients with cerebral artery stenosis was correlated with the incidence of cerebral infarction in the head and neck CTA, which was severe > medium > normal/low (P<0.05).

Conclusions

The ABCD2 score can accurately predict the early development from TIA to cerebral infarction. If it is used in combination with head-neck CTA; CTA combined ABCD2 score can further improve the accuracy of prediction, which makes it feasible for use in prediction of the development of vertebrobasilar TIA to cerebral infarction.

Predicting Long-Term Cardiovascular Events after Transient Ischemic Attacks: Carotid Artery Intima-Media Thickness or ABCD2 Score or Both?

Background

Patients who experienced transient ischemic attack (TIA) are at high-risk for cardiovascular events. This study aims to evaluate diagnostic value of carotid artery intima-media thickness (CIMT) and ABCD2 score for predicting cardiovascular events in long-term follow-up after TIA. We prospectively included sixty patients with TIA who admitted to hospital from March 2016 to August 2016.

Methods

Duplex ultrasonography of internal carotid arteries was performed. ABCD2 scores were evaluated for each patient. At a median follow-up of 20 months, patients were asked about new cardiovascular events. We used IBM SPSS software version 22.0 with Chi-squared, t-test, ANOVA, receiver operating characteristic, and area under the curve (AUC) analysis for our work.

Results

Sensitivity and negative predictive value of the combined score (ABCD2+CIMT) was the highest (96.3% and 90.9%, respectively), and the specificity and positive predictive value of the CIMT were the highest (57.5% and 63.1%, respectively) to predict cardiovascular events in long-term.

Conclusion

Compared to ABCD2 score, CIMT proved to be more accurate to predict cardiovascular events in long-term follow-ups (AUC = 0.736 vs. AUC = 0.640). However, adding CIMT value to ABCD2 score was even better (AUC = 0.750). Therefore, CIMT measurement in the ABCD2 score after TIA enables prediction of long-term cardiovascular events.

From Inpatient to Ambulatory Care: The Introduction of a Rapid Access Transient Ischaemic Attack Service

Background: Transient Ischaemic Attacks (TIA) should be treated as a medical emergency. While high-risk TIAs have higher stroke risks than low-risk patients, there is an inherent limitation to this risk stratification, as some low-risk patients may have undiagnosed high-risk conditions. Inequity of care for TIA patients was observed, such that high-risk patients received urgent assessment through acute admission, while low-risk patients faced long waits for clinical consultation. A redesign of the TIA service was planned to offer timely assessment for all patients and avoid acute admission for high-risk patients. Methods: Service reconfiguration was undertaken to set up a daily weekday rapid access TIA clinic where patients would be assessed, investigated, and treated. Results: A re-audit of clinic performance showed a significant increase in the number of patients seen in the ages of 18 to 52. The median time from referral to clinical consultation improved from 10 days to 1. There were similar significant improvements seen in median time to brain imaging (from 10.5 days to 1), and carotid ultrasound (from 10 days to all scans being performed on the same day). Conclusions: The redesigned service achieved the objective of offering urgent assessment and investigations for all TIA patients, including low-risk patients, while avoiding the acute admission for high-risk patients. We share our experience of establishing a successful rapid access ambulatory service without any additional resources.

Reducing time-to-unit among patients referred to an outpatient stroke assessment unit with a novel triage process: a prospective cohort study

Background

To evaluate the performance of a novel triage system for Transient Ischemic Attack (TIA) units built upon an existent clinical prediction rule (CPR) to reduce time to unit arrival, relative to the time of symptom onset, for true TIA and minor stroke patients. Differentiating between true and false TIA/minor stroke cases (mimics) is necessary for effective triage as medical intervention for true TIA/minor stroke is time-sensitive and TIA unit spots are a finite resource.

Methods

Prospective cohort study design utilizing patient referral data and TIA unit arrival times from a regional fast-track TIA unit on Vancouver Island, Canada, accepting referrals from emergency departments (ED) and general practice (GP). Historical referral cohort (N = 2942) from May 2013–Oct 2014 was triaged using the ABCD2 score; prospective referral cohort (N = 2929) from Nov 2014–Apr 2016 was triaged using the novel system. A retrospective survival curve analysis, censored at 28 days to unit arrival, was used to compare days to unit arrival from event date between cohort patients matched by low (0–3), moderate (4–5) and high (6–7) ABCD2 scores.

Results

Survival curve analysis indicated that using the novel triage system, prospectively referred TIA/minor stroke patients with low and moderate ABCD2 scores arrived at the unit 2 and 1 day earlier than matched historical patients, respectively.

Conclusions

The novel triage process is associated with a reduction in time to unit arrival from symptom onset for referred true TIA/minor stroke patients with low and moderate ABCD2 scores.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-2952-x) contains supplementary material, which is available to authorized users.

Long-term cardiovascular prognosis after transient ischemic attack: Associated predictors

OBJECTIVE

To determine long-term cardiovascular risk after TIA and to identify the factors associated with increased risk.

METHODS

This was a prospective observational registry of TIA patients admitted to the emergency room of our tertiary stroke center from June 2006 to January 2016. New vascular events (NVEs) were recorded from 3 months after TIA onset until June 2017, including both stroke and nonstroke events (coronary and peripheral disease). We registered TIA etiology, age, sex, vascular risk factors, radiologic data, and clinical TIA features and analyzed these variables in relation to NVE long-term risk.

RESULTS

In total, 676 patients 71.7 ± 13.7 years of age were included, with a mean follow-up of 48.8 ± 32.7 months. An NVE was detected in 173 patients (25.6%) without significant differences between event types (p = 0.84). Univariate analysis associated NVEs with etiologic subgroup, male sex, diabetes mellitus, hypertension, previous vascular disease, duration and clinical features of TIA, and signs of acute infarction. Multivariable analysis showed an independent association of NVEs with etiologic TIA subgroup, signs of acute infarction, and duration of TIA symptoms. Large artery atherosclerosis and cardioaortic embolism had the highest NVE risk, with a slightly higher percentage of nonstroke events. The small artery disease subgroup had the lowest NVE risk, with a higher percentage of stroke events.

CONCLUSIONS

Etiology subgroup was the main factor determining high long-term risk of vascular events in patients with TIA. Large artery atherosclerosis carried the highest vascular risk, both nonstroke and stroke, followed by cardioaortic embolism.

Imaging of Ischemic Stroke

PURPOSE OF REVIEW

This article provides an overview of cerebrovascular hemodynamics, acute stroke pathophysiology, and collateral circulation, which are pivotal in the modern imaging of ischemic stroke that guides the care of the patient with stroke.

RECENT FINDINGS

Neuroimaging provides extensive information on the brain and vascular health. Multimodal CT and MRI delineate the hemodynamics of ischemic stroke that may be used to guide treatment decisions and prognosticate regarding expected outcomes. Mismatch imaging with either CT or MRI may identify patients with salvageable regions who are at risk and likely to benefit from reperfusion therapy, even if they are outside the standard time window. Imaging of collateral circulation and determination of collateral grade may predict greater reperfusion, lower hemorrhage risk, and better functional outcome. Current neuroimaging technology also enables the identification of patients at high risk of hemorrhagic transformation or those who may be harmed by treatment or unlikely to benefit from it.

SUMMARY

This article reviews the use and impact of imaging for the patient with ischemic stroke, emphasizing how imaging builds upon clinical evaluation to establish diagnosis or etiology, reveal key pathophysiology, and guide therapeutic decisions.

When has service provision for transient ischaemic attack improved enough? A discrete event simulation economic modelling study

OBJECTIVES

The aim of this study was to examine the impact of transient ischaemic attack (TIA) service modification in two hospitals on costs and clinical outcomes.

DESIGN

Discrete event simulation model using data from routine electronic health records from 2011.

PARTICIPANTS

Patients with suspected TIA were followed from symptom onset to presentation, referral to specialist clinics, treatment and subsequent stroke.

INTERVENTIONS

Included existing versus previous (less same day clinics) and hypothetical service reconfiguration (7-day service with less availability of clinics per day).

OUTCOME MEASURES

The primary outcome of the model was the prevalence of major stroke after TIA. Secondary outcomes included service costs (including those of treating subsequent stroke) and time to treatment and attainment of national targets for service provision (proportion of high-risk patients (according to ABCD² score) seen within 24 hours).

RESULTS

The estimated costs of previous service provision for 490 patients (aged 74±12 years, 48.9% female and 23.6% high risk) per year at each site were £340 000 and £368 000, respectively. This resulted in 31% of high-risk patients seen within 24 hours of referral (47/150) with a median time from referral to clinic attendance/treatment of 1.15 days (IQR 0.93-2.88). The costs associated with the existing and hypothetical services decreased by £5000 at one site and increased £21 000 at the other site. Target attainment was improved to 79% (118/150). However, the median time to clinic attendance was only reduced to 0.85 days (IQR 0.17-0.99) and thus no appreciable impact on the modelled incidence of major stroke was observed (10.7 per year, 99% CI 10.5 to 10.9 (previous service) vs 10.6 per year, 99% CI 10.4 to 10.8 (existing service)).

CONCLUSIONS

Reconfiguration of services for TIA is effective at increasing target attainment, but in services which are already working efficiently (treating patients within 1-2 days), it has little estimated impact on clinical outcomes and increased investment may not be worthwhile.

Explicit diagnostic criteria for transient ischemic attacks to differentiate it from migraine with aura

Background The diagnosis of transient ischemic attacks is fraught with problems. The inter-observer agreement has repeatedly been shown to be low even in a neurological setting, and the specificity of the diagnosis is modest to low, reflected in a poor separation of transient ischemic attacks and mimics, particularly migraine with aura with its varied symptomatology. In other disease areas, explicit diagnostic criteria have improved sensitivity and specificity of diagnoses. We therefore present novel explicit diagnostic criteria for transient ischemic attacks tested for sensitivity and for specificity against migraine with aura. Methods The proposed criteria were developed using the format of the international headache classification. We drew upon the existing literature about clinical characteristics and diagnosis of migraine with aura and transient ischemic attacks. We tested the criteria for sensitivity in a prospectively-collected material of 120 patients with transient ischemic attacks diagnosed before we developed the criteria using extensive semi-structured interview forms in the acute phase after admission. Eligible patients had focal brain or retinal ischemia with resolution of symptoms within 24 hours without presence of new infarction on magnetic resonance imaging with diffusion weighted imaging (n = 112) or computed tomography (n = 8). These criteria were also tested for specificity against a Danish (n = 1390) and a Russian (n = 152) material of patients with migraine with aura diagnosed according to the International Classification of Headache Disorders edition 3 (beta). Results The sensitivity of the proposed criteria was 99% in patients with transient ischemic attacks. The specificity was 95% in the Danish material of patients with migraine with aura and 96% in the Russian material. Conclusions Proposed explicit diagnostic criteria for transient ischemic attacks showed both high specificity and sensitivity. They are likely to improve the emergency room diagnosis of transient ischemic attacks. Further testing in unselected materials referred to transient ischemic attacks clinics was beyond the scope of the present study but is recommended for future study.

Transient Ischemic Attack in Pediatric Patients With Moyamoya Disease: Clinical Features, Natural History, and Predictors of Stroke

BACKGROUND

Despite being the most common presentation in children with moyamoya, transient ischemic attack (TIA) in children has rarely been described. The aim of this study is to describe the clinical characteristics of TIAs in children with moyamoya and explore the risk factors for stroke after TIA.

METHODS

We reviewed 696 consecutive patients with moyamoya vasculopathy (155 pediatric patients and 541 adults) admitted to our hospital from 2009 to 2015 to identify pediatric patients with moyamoya with an initial presentation of TIA. We defined recurrent TIAs that involve more types of symptoms or symptom extensions as symptom progression. The risk factors for subsequent stroke were analyzed using time-to-event analyses.

RESULTS

We identified 60 pediatric patients with moyamoya who had presented with TIA (initial presentation age, 10.0 ± 3.5 years). Motor weakness (n = 51 [85%]) was the most common initial presentation. During follow-up, 55 patients (91.7%) had recurrent TIAs and 14 (23.3%) had subsequent strokes. We identified female gender (hazard ratio, 5.08; 95% confidence interval, 1.40-18.47; P = 0.01), Suzuki grade greater than 3 (hazard ratio, 4.01; 95% confidence interval, 1.16-13.82; P = 0.03), and symptom progression (hazard ratio, 5.31; 95% confidence interval, 1.65-17.14; P = 0.01) as independent predictors of future stroke events.

CONCLUSIONS

Transient ischemic attacks have a relatively high recurrence rate in children with moyamoya and are associated with subsequent stroke. We identified the female sex, Suzuki grade greater than  3, and symptom progression as independent predictors of future strokes.

Changes to white matter microstructure in transient ischemic attack: A longitudinal diffusion tensor imaging study

Transient ischemic attack (TIA) is associated with localized ischemic changes, identifiable by diffusion-weighted imaging. Past research has not considered whether TIA is also associated with diffuse changes to white matter microstructure; further past work has not tracked changes longitudinally. Here we examine whole-brain changes in fractional anisotropy (FA) in individuals with TIA presenting with sensorimotor symptoms. Twenty individuals with a recent (within 30 days) TIA and 12 healthy older adults were recruited. Participants underwent 3.0 T diffusion MRI at baseline; scans were repeated for the TIA group 90 days post-TIA. Track-based spatial statistics (TBSS) was used to conduct a voxel-wise analysis of FA between groups. FA was significantly lower in the TIA group relative to healthy controls, primarily in anterior white matter tracts including: forceps minor, anterior thalamic radiations, cingulum, inferior fronto-occipital fasciculus, and corticospinal tract. TBSS results informed an ROI-based longitudinal examination of FA in the TIA group. There were no changes to TBSS-identified clusters, forceps minor, or the corticospinal tract over time. There was lower FA in the anterior thalamic radiations in the TIA-affected hemisphere at baseline, but no difference between hemispheres at 90 days. In summary, individuals with TIA presenting with sensorimotor symptoms have decreased FA in tracts that are also implicated in sensorimotor function, which outlast the clinical symptoms associated with TIA. This suggests a more profound type of brain damage associated with TIA than has been typically described in past work. Diffusion tensor imaging may have utility as a marker of TIA-associated changes to white matter pathways. Hum Brain Mapp 38:5795-5803, 2017. © 2017 Wiley Periodicals, Inc.

Comparison of Stroke Prediction Accuracy of ABCD2 and ABCD3-I in Patients with Transient Ischemic Attack: A Meta-Analysis

BACKGROUND

A direct comparison of the stroke prediction utility of the ABCD2 and ABCD3-I scores has not been performed. Thus, we conducted a diagnostic meta-analysis and applied the results to a hypothetical cohort of 1000 patients with transient ischemic attack (TIA) to assess the power of stroke prediction by ABCD2 and ABCD3-I scores.

METHODS

Medline, PubMed, Embase, and manuscript references were searched to identify studies that directly compared the stroke predictive powers of ABCD2 and ABCD3-I scores. We conducted a diagnostic meta-analysis using bivariate random effects models, and the predictive powers of ABCD2 and ABCD3-I scores were assessed by their summary sensitivity and specificity. Then, we applied the results to a hypothetical cohort of 1000 patients with TIA to calculate the effect per 1000 patients triaged for stroke prevention in a virtual setting.

RESULTS

Of the 35 identified studies on ABCD2 and ABCD3-I, 6 studies (7364 participants) directly compared the diagnostic accuracies of ABCD2 and ABCD3-I scores for occurrence of a future stroke. The pooled sensitivities of ABCD2 versus ABCD3-I were 79.9% (62.2%-90.6%) versus 96.1% (90.2%-98.5%) at 7 days (P = .022), and 76.6% (63.8%-85.8%) versus 94.6% (88.9%-97.5%) at 90 days (P = .001). The pooled specificities of ABCD2 versus ABCD3-I were 29.2% (18.2%-43.3%) versus 17.7% (8.5%-33.3%) at 7 days (P = .214), and 40.3% (25.0%-57.7%) versus 20.2% (12.6%-30.6%) at 90 days (P = .032).

CONCLUSIONS

ABCD3-I scores had a better sensitivity but poorer specificity than ABCD2 scores. However, in community-based referring settings, it is more suitable to use ABCD2 at initial triage and deciding on urgency of specialist assessment. The prognostic utility of each of the components of the scores should be carefully considered rather than dichotomized scores during clinical triage.

Motor Impairments in Transient Ischemic Attack Increase the Odds of a Subsequent Stroke: A Meta-Analysis

Background and purpose

Transient ischemic attack (TIA) increases the risk for a subsequent stroke. Typical symptoms include motor weakness, gait disturbance, and loss of coordination. The association between the presence of motor impairments during a TIA and the chances of a subsequent stroke has not been examined. In the current meta-analysis, we examine whether the odds of a stroke are greater in TIA individuals who experience motor impairments as compared with those who do not experience motor impairments.

Methods

We conducted a systematic search of electronic databases as well as manual searches of the reference lists of retrieved articles. The meta-analysis included studies that reported an odds ratio relating motor impairments to a subsequent stroke, or the number of individuals with or without motor impairments who experienced a subsequent stroke. We examined these studies using rigorous meta-analysis techniques including random effects model, forest and funnel plots, I², publication bias, and fail-safe analysis.

Results

Twenty-four studies with 15,129 participants from North America, Australia, Asia, and Europe qualified for inclusion. An odds ratio of 2.11 (95% CI, 1.67–2.65, p = 0.000) suggested that the chances of a subsequent stroke are increased by twofolds in individuals who experience motor impairments during a TIA compared with those individuals who have no motor impairments.

Conclusion

The presence of motor impairments during TIA is a significantly high-risk clinical characteristic for a subsequent stroke. The current evidence for motor impairments following TIA relies exclusively on the clinical reports of unilateral motor weakness. A comprehensive examination of motor impairments in TIA will enhance TIA prognosis and restoration of residual motor impairments.

Inpatient versus Outpatient Management of TIA or Minor Stroke: Clinical Outcome

BACKGROUND

The management of patients with acute transient ischemic attack (TIA) or minor stroke is highly variable. Whether hospitalization of such patients significantly improves short-term clinical outcome is unknown. We assessed the short-term clinical outcome associated with inpatient versus outpatient management of patients with TIA or minor stroke.

METHODS

We evaluated a consecutive series of patients with acute TIA or minor ischemic stroke (NIH Stroke Scale score ≤ 3) presenting to a single emergency department (ED). We randomized patients to either hospital-based or outpatient-based management. All patients underwent interview and examination 7-10 days following the index event.

RESULTS

This study included 100 patients, 41 with TIA and 59 with minor stroke. Nineteen (46%) of the TIA patients and 29 (49%) of the minor stroke patients randomized to hospital management, and the remaining 22 TIA patients and 30 minor stroke patients randomized to outpatient-based management. In the patients with a minor stroke, neurologic worsening occurred in 6 out of 29 (21%) in the inpatient arm compared with 3 out of 30 (10%) in the outpatient arm (p = 0.3). In none of these cases was acute interventional therapy or need for urgent admission considered medically appropriate. In the patients with a TIA, recurrence of a TIA occurred in 2 out of 19 (11%) in the inpatient arm compared with 2 out of 22 (9%) in the outpatient arm (p = 1). None of the patients with a TIA randomized to the inpatient arm experienced a stroke compared with 1 out of 22 in the outpatient arm (p = 1). There were no deaths in either group.

CONCLUSION

Routine hospitalization of all patients with TIA or minor ischemic stroke may not positively affect short-term clinical outcome.

Imaging Parameters and Recurrent Cerebrovascular Events in Patients With Minor Stroke or Transient Ischemic Attack

IMPORTANCE

Neurological worsening and recurrent stroke contribute substantially to morbidity associated with transient ischemic attacks and strokes (TIA-S).

OBJECTIVE

To determine predictors of early recurrent cerebrovascular events (RCVEs) among patients with TIA-S and National Institutes of Health Stroke Scale scores of 0 to 3.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study was conducted at 2 tertiary care centers (Columbia University Medical Center, New York, New York, and Tulane University Medical Center, New Orleans, Louisiana) between January 1, 2010, and December 31, 2014. All patients with neurologist-diagnosed TIA-S with a National Institutes of Health Stroke Scale score of 0 to 3 who presented to the emergency department were included.

MAIN OUTCOMES AND MEASURES

The primary outcome (adjudicated by 3 vascular neurologists) was RCVE: neurological deterioration in the absence of a medical explanation or recurrent TIA-S during hospitalization.

RESULTS

Of the 1258 total patients, 1187 had no RCVEs and 71 had RCVEs; of this group, 750 patients (63.2%) and 39 patients (54.9%), respectively, were aged 60 years or older. There were 505 patients with TIA-S at Columbia University; 31 (6.1%) had RCVEs (15 patients had neurological deterioration only, 11 had recurrent TIA-S only, and 5 had both). The validation cohort at Tulane University consisted of 753 patients; 40 (5.3%) had RCVEs (24 patients had neurological deterioration only and 16 had both). Predictors of RCVE in multivariate models in both cohorts were infarct on neuroimaging (computed tomographic scan or diffusion-weighted imaging sequences on magnetic resonance imaging) (Columbia University: not applicable and Tulane University: odds ratio, 1.75; 95% CI, 0.82-3.74; P = .15) and large-vessel disease etiology (Columbia University: odds ratio, 6.69; 95% CI, 3.10-14.50 and Tulane University: odds ratio, 8.13; 95% CI, 3.86-17.12; P < .001). There was an increase in the percentage of patients with RCVEs when both predictors were present. When neither predictor was present, the rate of RCVE was extremely low (up to 2%). Patients with RCVEs were less likely to be discharged home in both cohorts.

CONCLUSIONS AND RELEVANCE

In patients with minor stroke, vessel imaging and perhaps neuroimaging parameters, but not clinical scores, were associated with RCVEs in 2 independent data sets. Prospective studies are needed to validate these predictors.

Diagnosis and Management of Transient Ischemic Attack

PURPOSE OF REVIEW

This article reviews the diagnosis, investigation, and recommended management after a transient ischemic attack (TIA) and discusses how to make an accurate diagnosis, including the diagnosis of mimics of TIAs.

RECENT FINDINGS

Up to a 10% risk of recurrent stroke exists after a TIA, and up to 80% of this risk is preventable with urgent assessment and treatment. Imaging of the brain and intracranial and extracranial blood vessels using CT, CT angiography, carotid Doppler ultrasound, and MRI is an important part of the diagnostic assessment. Treatment options include anticoagulation for atrial fibrillation, carotid revascularization for symptomatic carotid artery stenosis, antiplatelet therapy, and vascular risk factor reduction strategies.

SUMMARY

TIA offers the greatest opportunity to prevent stroke that physicians encounter. A TIA should be treated as a medical emergency, as up to 80% of strokes after TIA are preventable.

Acute Stroke and Transient Ischemic Attack in the Outpatient Clinic

Ischemic stroke is cause of substantial death and disability in the United States. Transient ischemic attack, a precursor to ischemic stroke, conveys a high risk of recurrent stroke within 90 days from event. These conditions are highly preventable and treatable. The cause is heterogenous and includes atherothrombosis, cardioembolism, lacunar disease, or cryptogenic, and some uncommon causes, such as arterial dissection and prothrombotic states. The emergent evaluation includes establishing time of onset, vital signs, glucose level, and severity of the deficit.

Association of multiple infarctions and ICAS with outcomes of minor stroke and TIA

OBJECTIVE

To estimate the association of different patterns of infarction and intracranial arterial stenosis (ICAS) with the prognosis of acute minor ischemic stroke and TIA.

METHODS

We derived data from the Clopidogrel in High-risk Patients with Acute Nondisabling Cerebrovascular Events (CHANCE) trial. A total of 1,089 patients from 45 of 114 participating sites of the trial undergoing baseline MRI/angiography were included in this subgroup analysis. Patterns of infarction and ICAS were recorded for each individual. The primary efficacy outcome was an ischemic stroke at the 90-day follow-up. We assessed the associations between imaging patterns and prognosis of patients using multivariable Cox regression models.

RESULTS

Among the 1,089 patients included in this subgroup analysis, 93 (8.5%) patients had a recurrent ischemic stroke at 90 days. Compared with those without infarction or ICAS, patients with single infarction with ICAS (11.9% vs 1.3%, hazard ratio [HR] 6.25, 95% confidence intervals [CIs] 1.40-27.86, p = 0.02) and single infarction without ICAS (6.8% vs 1.3%, HR 4.65, 95% CI 1.05-20.64, p = 0.04) were all associated with an increased risk of ischemic stroke at 90 days. Patients with both multiple infarctions and ICAS were associated with approximately 13-fold risk of ischemic stroke at 90 days (18.0% vs 1.3%, HR 13.14, 95% CI 2.96-58.36, p < 0.001).

CONCLUSIONS

The presence of multiple infarctions and ICAS were both associated with an increased risk of 90-day ischemic stroke in patients with minor stroke or TIA, while the presence of both imaging features had a combined effect.

CLINICALTRIALSGOV IDENTIFIER

NCT00979589.

Stroke

In the past decade, the definition of stroke has been revised and major advances have been made for its treatment and prevention. For acute ischaemic stroke, the addition of endovascular thrombectomy of proximal large artery occlusion to intravenous alteplase increases functional independence for a further fifth of patients. The benefits of aspirin in preventing early recurrent ischaemic stroke are greater than previously recognised. Other strategies to prevent recurrent stroke now include direct oral anticoagulants as an alternative to warfarin for atrial fibrillation, and carotid stenting as an alternative to endarterectomy for symptomatic carotid stenosis. For acute intracerebral haemorrhage, trials are ongoing to assess the effectiveness of acute blood pressure lowering, haemostatic therapy, minimally invasive surgery, anti-inflammation therapy, and neuroprotection methods. Pharmacological and stem-cell therapies promise to facilitate brain regeneration, rehabilitation, and functional recovery. Despite declining stroke mortality rates, the global burden of stroke is increasing. A more comprehensive approach to primary prevention of stroke is required that targets people at all levels of risk and is integrated with prevention strategies for other diseases that share common risk factors.

Long-Term Risk of Stroke after Transient Ischemic Attack

Background: In the absence of active management, the stroke risk after a transient ischemic attack (TIA) may be high. Almost 10 years ago, the results of the EXPRESS and SOS-TIA studies called for a more rapid management of TIA patients. The purpose of this study was to investigate the other stroke risks in the longer term, after the implementation of a more active approach to TIA. We also wanted to assess the predictive value of the ABCD2 score in this context. Methods: Riksstroke is the national stroke registry in Sweden. Data from Riksstroke's TIA module, and the national cause-of-death register, for the years 2011 and 2012 were used in this study. Stroke occurrence was monitored via Riksstroke. Cox's regression was used for risk evaluation. The predictive value of the ABCD2 score was assessed by calculating the area under the receiver operating characteristics curve. Results: A total of 15,068 TIA episodes occurred in 14,102 patients. The follow-up time varied between 0 and 819 days, with an average of 417 days. The mortality for all TIA patients during the follow-up time was 7.1%. Of the unique patients, 545 had one or more strokes (3.9%), corresponding to 34 events per 1,000 person years. Significant risk factors for stroke were: age, previous TIA, atrial fibrillation (AF), oral anticoagulant (OAC) treatment, hypertension treatment, and the ABCD2 items speech impairment, unilateral weakness, and diabetes mellitus. The ABCD2 score correlated with a subsequent stroke, but its predictive value was low. Conclusion: The risk of stroke is low after the acute phase of a TIA, probably lower than in previous studies. This may be due to better secondary prevention in recent years. Several risk factors predict stroke, notably hypertensive treatment, which may be inadequate; and AF, where OACs may be under-used. It is difficult to identify the role of the ABCD2 score in clinical practice.

Validation and comparison of imaging-based scores for prediction of early stroke risk after transient ischaemic attack: a pooled analysis of individual-patient data from cohort studies

BACKGROUND

Identification of patients at highest risk of early stroke after transient ischaemic attack has been improved with imaging based scores. We aimed to compare the validity and prognostic utility of imaging-based stroke risk scores in patients after transient ischaemic attack.

METHODS

We did a pooled analysis of published and unpublished individual-patient data from 16 cohort studies of transient ischaemic attack done in Asia, Europe, and the USA, with early brain and vascular imaging and follow up. All patients were assessed by stroke specialists in hospital settings as inpatients, in emergency departments, or in transient ischaemic attack clinics. Inclusion criteria were stroke-specialist confirmed transient ischaemic attack, age of 18 years or older, and MRI done within 7 days of index transient ischaemic attack and before stroke recurrence. Multivariable logistic regression was done to analyse the predictive utility of abnormal diffusion-weighted MRI, carotid stenosis, and transient ischaemic attack within 1 week of index transient ischaemic attack (dual transient ischaemic attack) after adjusting for ABCD2 score. We compared the prognostic utility of the ABCD2, ABCD2-I, and ABCD3-I scores using discrimination, calibration, and risk reclassification.

FINDINGS

In 2176 patients from 16 cohort studies done between 2005 and 2015, after adjusting for ABCD2 score, positive diffusion-weighted imaging (odds ratio [OR] 3·8, 95% CI 2·1-7·0), dual transient ischaemic attack (OR 3·3, 95% CI 1·8-5·8), and ipsilateral carotid stenosis (OR 4·7, 95% CI 2·6-8·6) were associated with 7 day stroke after index transient ischaemic attack (p<0·001 for all). 7 day stroke risk increased with increasing ABCD2-I and ABCD3-I scores (both p<0·001). Discrimination to identify early stroke risk was improved for ABCD2-I versus ABCD2 (2 day c statistic 0·74 vs 0·64; p=0·006). However, discrimination was further improved by ABCD3-I compared with ABCD2 (2 day c statistic 0·84 vs 0·64; p<0·001) and ABCD2-I (c statistic 0·84 vs 0·74; p<0·001). Early stroke risk reclassification was improved by ABCD3-I compared with ABCD2-I score (clinical net reclassification improvement 33% at 2 days).

INTERPRETATION

Although ABCD2-I and ABCD3-I showed validity, the ABCD3-I score reliably identified highest-risk patients at highest risk of a stroke after transient ischaemic attack with improved risk prediction compared with ABCD2-I. Transient ischaemic attack management guided by ABCD3-I with immediate stroke-specialist assessment, urgent MRI, and vascular imaging should now be considered, with monitoring of safety and cost-effectiveness.

FUNDING

Health Research Board of Ireland, Irish Heart Foundation, Irish Health Service Executive, Irish National Lottery, National Medical Research Council of Singapore, Swiss National Science Foundation, Bangerter-Rhyner Foundation, Swiss National Science Foundation, Swisslife Jubiläumsstiftung for Medical Research, Swiss Neurological Society, Fondazione Dr Ettore Balli (Switzerland), Clinical Trial Unit of University of Bern, South Korea's Ministry for Health, Welfare, and Family Affairs, UK Wellcome Trust, Wolfson Foundation, UK Stroke Association, British Heart Foundation, Dunhill Medical Trust, National Institute of Health Research (NIHR), Medical Research Council, and the NIHR Oxford Biomedical Research Centre.

High ABCD2 Scores and In-Hospital Interventions following Transient Ischemic Attack

Background and Purpose

Following transient ischemic attack (TIA), there is increased risk for ischemic stroke. The American Heart Association recommends admission of patients with ABCD² scores ≥3 for observation, rapid performance of diagnostic tests, and potential acute intervention. We aimed to determine if there is a relationship between ABCD² scores, in-hospital ischemic events, and in-hospital treatments after TIA admission.

Methods

We reviewed consecutive patients admitted between 2006 and 2011 following a TIA, defined as transient focal neurological symptoms attributed to a specific vascular distribution and lasting <24 h. Three interventions were prespecified: anticoagulation for atrial fibrillation, carotid or intracranial revascularization, and intravenous or intra-arterial reperfusion therapies. We compared rates of in-hospital recurrent TIA or ischemic stroke and the receipt of interventions among patients with low (<3) versus high (≥3) ABCD² scores.

Results

Of 249 patients, 11 patients (4.4%) had recurrent TIAs or strokes during their stay (8 TIAs, 3 strokes). All 11 had ABCD² scores ≥3, and no neurological events occurred in patients with lower scores (5.1 vs. 0%; p = 0.37). Twelve patients (4.8%) underwent revascularization for large artery stenosis, 16 (6.4%) were started on anticoagulants, and no patient received intravenous or intra-arterial reperfusion therapy. The ABCD² score was not associated with anticoagulation (p = 0.59) or revascularization (p = 0.20).

Conclusions

Higher ABCD² scores may predict early ischemic events after TIA but do not predict the need for intervention. Outpatient evaluation for those with scores <3 would potentially have delayed revascularization or anticoagulant treatment in nearly one-fifth of ‘low-risk’ patients.

The Value of ABCD2F Scoring System (ABCD2 Combined with Atrial Fibrillation) to Predict 90-Day Recurrent Brain Stroke

Background. The ABCD2 score is now identified as a useful clinical prediction rule to determine the risk for stroke in the days following brain ischemic attacks. Aim. The present study aimed to introduce a new scoring system named "ABCD2F" and compare its value with the previous ABCD2 system to predict recurrent ischemic stroke within 90 days of the initial cerebrovascular accident (CVA). Methods. 138 consecutive patients with the final diagnosis of ischemic CVA or TIAs who referred to emergency ward of Rasoul-e-Akram general hospital in Tehran from September 2012 to December 2013 were eligible. By adding a new score in the presence of atrial fibrillation to ABCD2 system, the new scoring system as ABCD2F was introduced and the risk stratification was done again on this new system. Results. The area under the curve for ABCD2 was 0.434 and for ABCD2F it was 0.452 indicating low value of both systems for assessing recurrence of stroke within 90 days of primary event. Multivariable logistic regression analysis showed that none of the baseline factors could predict 90-day recurrent stroke. Conclusion. ABCD2 and/or atrial fibrillation are not good scoring candidates for assessing the risk of recurrent stroke within first 90 days.

Minor Stroke and Transient Ischemic Attack: Research and Practice

A majority of patients with ischemic stroke present with mild deficits for which aggressive management is not often pursued. Comprehensive work-up and appropriate intervention for minor strokes and transient ischemic attacks (TIAs) point toward better patient outcomes, lower costs, and fewer cases of disability. Imaging is a key modality to guide treatment and predict stroke recurrence. Patients with large vessel occlusions have been found to suffer worse outcomes and could benefit from intervention. Whether intravenous thrombolytic therapy decreases disability in minor stroke patients and whether acute endovascular intervention improves functional outcomes in patients with minor stroke and known large vessel occlusion remain controversial. Studies are ongoing to determine ideal antiplatelet therapy for stroke and TIA, while ongoing statin therapy, surgical management for patients with carotid stenosis, and anticoagulation for patients with atrial fibrillation have all been proven to decrease the rate of stroke recurrence and improve outcomes. This review summarizes the current evidence and discusses the standard of care for patients with minor stroke and TIA.

Validation of ABCD2 scores ascertained by referring clinicians: a retrospective transient ischaemic attack clinic cohort study

INTRODUCTION

Transient ischaemic attack (TIA) services routinely use ABCD2 scores ascertained by referring clinicians to triage patients. Most ABCD2 validation studies have used ABCD2 scores calculated by stroke-specialist investigators and not referring clinicians. This study aimed to assess the usefulness of referring clinicians' ABCD2 scores in predicting strokes.

METHODS

A retrospective study of a TIA clinic cohort from Gloucester, UK, followed up for 4 years from 2010 to 2012. ABCD2 scores were dichotomised to high risk-ABCD2≥4 and low risk-ABCD2<4. Outcomes of interest were subsequent stroke and stroke or TIA. Survival analysis was used determine the cumulative probability of these outcomes and to identify if ABCD2 risk category was associated with stroke.

RESULTS

Of 1067 (284 high risk, 783 low risk) patients, 49.6% were classified by the clinic stroke physicians as TIA/minor stroke and 50.4% as mimics. Follow-up was for a median of 34.9 (IQR 27.7-41.6) months with 56 strokes and 106 strokes/TIA. The number of strokes by 7 days, 90 days and 48 months, respectively, were: high risk 0, 2 and 20 and low risk 2, 6 and 36 (p=0.21). Unadjusted HR for subsequent stroke was 1.41 (95% CI 0.82 to 2.46) in the high-risk group compared with the low-risk group and HR adjusted for the diagnosis of TIA/stroke was 1.2 (95% CI 0.69 to 2.08).

CONCLUSIONS

ABCD2 scores recorded by referring clinicians did not identify patients at high risk of subsequent stroke, suggesting that the score should not be used for TIA clinic triage.

Diagnosis of TIA (DOT) score--design and validation of a new clinical diagnostic tool for transient ischaemic attack

BACKGROUND

The diagnosis of Transient Ischaemic Attack (TIA) can be difficult and 50-60% of patients seen in TIA clinics turn out to be mimics. Many of these mimics have high ABCD2 scores and fill urgent TIA clinic slots inappropriately. A TIA diagnostic tool may help non-specialists make the diagnosis with greater accuracy and improve TIA clinic triage. The only available diagnostic score (Dawson et al) is limited in scope and not widely used. The Diagnosis of TIA (DOT) Score is a new and internally validated web and mobile app based diagnostic tool which encompasses both brain and retinal TIA.

METHODS

The score was derived retrospectively from a single centre TIA clinic database using stepwise logistic regression by backwards elimination to find the best model. An optimum cutpoint was obtained for the score. The derivation and validation cohorts were separate samples drawn from the years 2010/12 and 2013 respectively. Receiver Operating Characteristic (ROC) curves and area under the curve (AUC) were calculated and the diagnostic accuracy of DOT was compared to the Dawson score. A web and smartphone calculator were designed subsequently.

RESULTS

The derivation cohort had 879 patients and the validation cohort 525. The final model had seventeen predictors and had an AUC of 0.91 (95% CI: 0.89-0.93). When tested on the validation cohort, the AUC for DOTS was 0.89 (0.86-0.92) while that of the Dawson score was 0.77 (0.73-0.81). The sensitivity and specificity of the DOT score were 89% (CI: 84%-93%) and 76% (70%-81%) respectively while those of the Dawson score were 83% (78%-88%) and 51% (45%-57%). Other diagnostic accuracy measures (DOT vs. Dawson) include positive predictive values (75% vs. 58%), negative predictive values (89% vs. 79%), positive likelihood ratios (3.67 vs. 1.70) and negative likelihood ratios (0.15 vs. 0.32).

CONCLUSION

The DOT score shows promise as a diagnostic tool for TIA and requires independent external validation before it can be widely used. It could potentially improve the triage of patients assessed for suspected TIA.

Cerebrovascular disease

With 16.9 million people who suffered a first-ever stroke in 2010 worldwide, stroke is a very common vascular disease. Epidemiologic studies have played an essential role in assessing this burden and in detecting the risk factors for stroke. Primary prevention of these risk factors, primarily hypertension, smoking, diabetes, and atrial fibrillation, has reduced the incidence in high-income countries. However, stroke remains a major cause of death and disability, and therefore research should be continued. Subarachnoid hemorrhages are less prevalent than strokes but have an even higher risk of death. Similar to stroke, epidemiologic studies identified smoking and hypertension as its most important risk factors, together with excessive alcohol intake. Although rare, arterial dissections, CADASIL, arteriovenous malformations, venous sinus thrombosis, moyamoya disease, and vasculitis can lead to serious symptoms. The burden and risk factors of those rare diseases are more challenging to assess. Whenever possible, they should be recognized in a timely manner for their increased risk of stroke, but most often they are diagnosed only at the time of stroke. Some cerebrovascular abnormalities do not result in immediate symptoms. This subclinical cerebrovascular disease includes silent infarcts, white-matter lesions, and microbleeds, and is incidentally found by neuroimaging. These lesions are not innocent, as several epidemiologic studies have associated subclinical cerebrovascular disease with an increased risk of stroke, cognitive decline, dementia, and death.