Analyzing recurrent events in multiple sclerosis: a review of statistical models with application to the MSOAC database

Patients with multiple sclerosis (MS) are susceptible to experience recurrent events of disability progression and relapses. Many studies still focus on analyzing MS events with traditional methods such as Cox proportional hazards, Poisson, and logistic regression that either ignore subsequent events or fail to account for overdispersion and dependency between events. The aim of this study was to conduct a literature review to identify the main recurrent event models, with subsequent application of these models to the Multiple Sclerosis Outcome Assessments Consortium (MSOAC) placebo database. A total of nine main recurrent event models were identified, compared and applied to the MSOAC database to evaluate the effect of the disease course on the number of changes in the Expanded Disability Status Scale (EDSS) and relapse rate. Recurrent events methods have provided more precise estimates than traditional methods. Despite the similarities in common and event-specific estimates for clinical MS outcomes, the interpretations of the parameter estimates resulting from the models are different. Medical researchers should prioritize recurrent event methods in their statistical plans to avoid information loss and improve the precision of estimated effects.

The role of the HINTS exam, TriAGe+ score, and ABCD2 score in predicting stroke in acute vertigo patients in the ED

OBJECTIVE

Posterior circulation stroke can mimic benign causes of vertigo, presenting with no obvious neurologic signs. Differentiating central from peripheral causes remains a challenge. We aimed to compare the diagnostic accuracy of three bedside screening tools for cerebrovascular causes of vertigo: HINTS examination, ABCD2 score, and TriAGe+ score.

METHOD

We conducted a single-center, prospective, observational study. Our primary outcome was to determine the diagnostic accuracy of the HINTS exam, ABCD2 score, and TriAGe+ score for predicting stroke in patients presenting with isolated dizziness or vertigo. Receiver operating characteristic (ROC) curve analysis was performed to determine the best cut-off scores.

RESULTS

357 patients were recruited, of which 58 were diagnosed with stroke. The sensitivity and specificity of the HINTS exam were 100% and 85.9%, respectively. At a cut-off ≥ 10 for the TriAGe+ score, a sensitivity of 46.6% and a specificity of 96.3% was found. The sensitivity and specificity of the ABCD2 score (≥4) were 65.5% and 68.6%. AUC values for HINTS, ABCD2, and TriAGe+ scores were 0.88, 0.71, and 0.88, respectively. The TriAGe+ score and HINTS exam showed the same diagnostic performance. The exclusion power of the HINTS exam was higher due to the negative LR of 0.0, whereas the diagnostic power of the TriAGe+ score was higher due to the positive LR of 12.65.

CONCLUSION

The diagnostic accuracy of the HINTS exam and the TriAGE+ score was better than the ABCD2 score. In our cohort, the HINTS exam was highly sensitive, whereas the specificity of the TriAGe+ score was better than other tests. Clinical experience and training are essential for a reliable HINTS exam, whereas the TriAGe+ score, with its practical structure, could help clinicians identify stroke in the chaotic ED environment.

Diabetes Mellitus and Risk of Future Stroke: Evidence From CHARLS and Mendelian Randomization Analyses

OBJECTIVES

This study leveraged the China Health and Retirement Longitudinal Study (CHARLS) to explore the association between diabetes and stroke in middle-aged and older adults in East Asia and assess the causality of this relationship using Mendelian randomization.

METHODS

Data from the 2011-2020 CHARLS cohort identified individuals with diabetes at baseline. Stroke incidence was self-reported through standardized questionnaires. Logistic regression and restricted cubic spline analysis examined the relationship between diabetes and stroke risk alongside nonlinear correlations between glucose levels and stroke. Mendelian randomization clarified the causal link and analyzed the mediating effect between diabetes and stroke using genetic methods.

RESULTS

In the study population aged 45 and above, stroke incidence was 5.99% in normoglycemic, 6.82% in prediabetic, and 9.93% in diabetic individuals. Over 7 years, 473 strokes occurred. Diabetes was associated with a 1.35-fold increased stroke risk compared to normoglycemia (OR = 1.35; 95% CI: 1.03-1.79). Subgroup analyses highlighted higher stroke risks in middle-aged women, nonsmokers, and nondrinkers. Mendelian randomization supports a genetic causal relationship between diabetes and stroke. Diabetes may indirectly lead to stroke through the mediating effects of hypertension and high cholesterol.

CONCLUSION

The findings confirm a significant association and causal link between diabetes and stroke risk in an East Asian population. In addition, the results indicate that controlling blood glucose in prediabetic individuals reduces stroke risk, with no similar benefits in diabetes.

Emergency medicine updates: Transient ischemic attack

INTRODUCTION

Transient ischemic attack (TIA) is a condition commonly evaluated for in the emergency department (ED). Therefore, it is important for emergency clinicians to be aware of the current evidence regarding the diagnosis and management of this disease.

OBJECTIVE

This paper evaluates key evidence-based updates concerning TIA for the emergency clinician.

DISCUSSION

TIA is a harbinger of ischemic stroke and can result from a variety of pathologic causes. While prior definitions incorporated symptoms resolving within 24 h, modern definitions recommend a tissue-based definition utilizing advanced imaging to evaluate for neurologic injury and the etiology. In the ED, emergent evaluation includes assessing for current signs and symptoms of neurologic dysfunction, appropriate imaging to investigate for minor stroke or stroke risk, and arranging appropriate disposition and follow up to mitigate risk of subsequent ischemic stroke. Imaging should include evaluation of great vessels and intracranial arteries, as well as advanced cerebral imaging to evaluate for minor or subclinical stroke. Non-contrast computed tomography (CT) has limited utility for this situation; it can rule out hemorrhage or a large mass causing symptoms but should not be relied on for any definitive diagnosis. Noninvasive imaging of the cervical vessels can also be used (CT angiography or Doppler ultrasound). Treatment includes antithrombotic medications if there are no contraindications. Dual antiplatelet therapy may reduce the risk of recurrent ischemic events in higher risk patients, while anticoagulation is recommended in patients with a cardioembolic source. A variety of scoring systems or tools are available that seek to predict stroke risk after a TIA. The Canadian TIA risk score appears to have the best diagnostic accuracy. However, these scores should not be used in isolation. Disposition may include admission, management in an ED-based observation unit with rapid diagnostic protocol, or expedited follow-up in a specialty clinic.

CONCLUSIONS

An understanding of literature updates concerning TIA can improve the ED care of patients with TIA.

Predictive value of whole-brain CT perfusion combined with ABCD3 score for short-term secondary cerebral infarction after TIA

Objective

To investigate the predictive value of Whole Brain CT Perfusion (WB-CTP) combined with the ABCD3 score in patients with transient ischemic attack (TIA).

Methods

A total of 336 TIA patients with TIA underwent WB-CTP and ABCD3 score assessment within 48 h of admission. Spearman correlation test was performed to analyze the relationship between the degree of vascular stenosis, relative perfusion values, and ABCD3 score. Logistic regression analysis was used to identify independent risk factors for secondary cerebral infarction. Receiver operating characteristic (ROC) curves were generated to evaluate the predictive value of relative cerebral blood flow (rCBF), degree of vascular stenosis, ABCD3 score, and the WB-CTP-ABCD3 combined model for secondary cerebral infarction after TIA. Calibration curves and H-L tests were used to evaluate the predictive efficacy of the model.

Results

Among the 336 TIA patients, 143 showed abnormal perfusion areas and 146 had responsible vessel stenosis. The degree of vascular stenosis, relative time-to-maximum (rTmax), and relative mean transit time (rMTT) were positively correlated with the ABCD3 score, while rCBF and relative cerebral blood volume (rCBV) were negatively correlated with the ABCD3 score. ROC curve analysis identified a cutoff value of 0.8205 for rCBF, with a sensitivity of 84.10% and specificity of 58.10% for distinguishing the cerebral infarction group from the non-cerebral infarction group. Furthermore, rCBF ≤ 0.8205, degree of vascular stenosis, and ABCD3 score > 6 were identified as independent risk factors for secondary cerebral infarction in TIA patients within 90 days in TIA patients. The AUC of the WB-CTP-ABCD3 combined model for predicting secondary cerebral infarction within 90 days was 0.836. The model risk was assessed by plotting calibration curves. The value of p for the H-L goodness of fit test was 0.366 (p > 0.05), which indicated that the difference between the obtained model and the perfect model were statistically insignificant.

Conclusion

The combined model of WB-CTP-ABCD3 shows promise as a valuable method for predicting secondary cerebral infarction within 90 days following TIA.

Transient ischemic attack events and incident cardiovascular and non-cardiovascular complications: Observations from a large diversified multimorbid cohort

Background:

Transient ischemic attack (TIA) is a strong signal prompting the incidence of future cardiovascular and non-cardiovascular complications, in light of recent debate on the so-called “stroke-heart syndrome.” We aimed to investigate the relation of TIAs to incident clinical events.

Methods:

Patients were drawn from three health plans with a wide spectrum of age groups and a wide mix of socio-economic/disability status. Two TIA cohorts in a retrospective design were used to achieve the study specific aims: (i) to investigate the incidence of TIA and associated cardiovascular and non-cardiovascular complications within 30 and 90 days from the onset of incident TIA events; and (ii) to examine the potential risk factors for developing incident TIA events in the general population with/without a history of prior stroke.

Results:

The incident TIA cohort consisted of 53,716 patients with an average age of 64.2 years (SD 15.2) and 46.1% male. Following TIA, the incidence proportions of ischemic stroke within 30 and 90 days were 2.7% and 3.8%, respectively, and for incident acute coronary syndrome being 0.94 and 1.84, respectively. Ventricular arrhythmia had proportions of 1.2 and 2.14, respectively within 30 and 90 days, with acute heart failure having values of 0.49 and 0.923. About 45% or more of the cardiovascular and non-cardiovascular complications occurred in the first 30 days following the incident TIA cases. About one-third of the recurrent TIA cases followed the incident TIA cases within a span of 30 days. Amongst comorbidities with stroke in the comorbid history, prior stroke provided the strongest risk factor in terms of odds ratio (OR = 8.34, 95% CI 7.21–9.66) for incident TIA events. Age was strongly associated with incident TIA events. Without a prior history of stroke (ischemic stroke/transient ischemic attack/thrombo-embolic events), valvular disease was the strongest risk factor from among the comorbidities (OR-1.87, 95% CI 1.51–2.32). Age also provided strong associations with incident TIA events.

Conclusions:

Following a TIA, there was a high risk of stroke, acute coronary syndrome, ventricular arrhythmia, acute heart failure, and non-cardiovascular complications.

Diagnostic accuracy of the physical examination in emergency department patients with acute vertigo or dizziness: A systematic review and meta-analysis for GRACE-3

BACKGROUND

History and physical examination are key features to narrow the differential diagnosis of central versus peripheral causes in patients presenting with acute vertigo. We conducted a systematic review and meta-analysis of the diagnostic test accuracy of physical examination findings.

METHODS

This study involved a patient-intervention-control-outcome (PICO) question: (P) adult ED patients with vertigo/dizziness; (I) presence/absence of specific physical examination findings; and (O) central (ischemic stroke, hemorrhage, others) versus peripheral etiology. Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) was assessed.

RESULTS

From 6309 titles, 460 articles were retrieved, and 43 met the inclusion criteria: general neurologic examination-five studies, 869 patients, pooled sensitivity 46.8% (95% confidence interval [CI] 32.3%-61.9%, moderate certainty) and specificity 92.8% (95% CI 75.7%-98.1%, low certainty); limb weakness/hemiparesis-four studies, 893 patients, sensitivity 11.4% (95% CI 5.1%-23.6%, high) and specificity 98.5% (95% CI 97.1%-99.2%, high); truncal/gait ataxia-10 studies, 1810 patients (increasing severity of truncal ataxia had an increasing sensitivity for central etiology, sensitivity 69.7% [43.3%-87.9%, low] and specificity 83.7% [95% CI 52.1%-96.0%, low]); dysmetria signs-four studies, 1135 patients, sensitivity 24.6% (95% CI 15.6%-36.5%, high) and specificity 97.8% (94.4%-99.2%, high); head impulse test (HIT)-17 studies, 1366 patients, sensitivity 76.8% (64.4%-85.8%, low) and specificity 89.1% (95% CI 75.8%-95.6%, moderate); spontaneous nystagmus-six studies, 621 patients, sensitivity 52.3% (29.8%-74.0%, moderate) and specificity 42.0% (95% CI 15.5%-74.1%, moderate); nystagmus type-16 studies, 1366 patients (bidirectional, vertical, direction changing, or pure torsional nystagmus are consistent with a central cause of vertigo, sensitivity 50.7% [95% CI 41.1%-60.2%, moderate] and specificity 98.5% [95% CI 91.7%-99.7%, moderate]); test of skew-15 studies, 1150 patients (skew deviation is abnormal and consistent with central etiology, sensitivity was 23.7% [95% CI 15%-35.4%, moderate] and specificity 97.6% [95% CI 96%-98.6%, moderate]); HINTS (head impulse, nystagmus, test of skew)-14 studies, 1781 patients, sensitivity 92.9% (95% CI 79.1%-97.9%, high) and specificity 83.4% (95% CI 69.6%-91.7%, moderate); and HINTS+ (HINTS with hearing component)-five studies, 342 patients, sensitivity 99.0% (95% CI 73.6%-100%, high) and specificity 84.8% (95% CI 70.1%-93.0%, high).

CONCLUSIONS

Most neurologic examination findings have low sensitivity and high specificity for a central cause in patients with acute vertigo or dizziness. In acute vestibular syndrome (monophasic, continuous, persistent dizziness), HINTS and HINTS+ have high sensitivity when performed by trained clinicians.

ABCD2, ABCD2-I, and OTTAWA scores for stroke risk assessment: a direct retrospective comparison

Transient ischemic attack (TIA) is a neurologic emergency characterized by cerebral ischemia eliciting a temporary focal neurological deficit. Many clinical prediction scores have been proposed to assess the risk of stroke after TIA; however, studies on their clinical validity and comparisons among them are scarce. The objective is to compare the accuracy of ABCD², ABCD²-I, and OTTAWA scores in the prediction of a stroke at 7, 90 days, and 1 year in patients presenting with TIA. Single-centre, retrospective study including patients with TIA admitted to the Emergency Department of our third-level, University Hospital, between 2018 and 2019. Five hundred three patients were included. Thirty-nine (7.7%) had a stroke within 1 year from the TIA: 9 (1.7%) and 24 (4.7%) within 7 and 90 days, respectively. ABCD², ABCD²-I, and OTTAWA scores were significantly higher in patients who developed a stroke. AUROCs ranged from 0.66 to 0.75, without statistically significant differences at each time-point. Considering the best cut-off of each score, only ABCD² > 3 showed a sensitivity of 100% only in the prediction of stroke within 7 days. Among clinical items of each score, duration of symptoms, previous TIA, hemiparesis, speech disturbance, gait disturbance, previous cerebral ischemic lesions, and known carotid artery disease were independent predictors of stroke. Clinical scores have moderate prognostic accuracy for stroke after TIA. Considering the independent predictors for stroke, our study indicates the need to continue research and prompts the development of new tools on predictive scores for TIA.

Stroke risk after ocular cranial nerve palsy - A systematic review and meta-analysis

BACKGROUND

Isolated ischemic ocular cranial nerve palsies (OCNP) involving the 3rd, 4th and 6th cranial nerves (CN) are prevalent conditions in ophthalmic practice. However, it is not clearly established whether such patients are at increased risk of stroke after onset of OCNPs.

METHODS

Medline, PubMed, Embase and Cochrane Central registers were systematically searched for eligible studies comparing isolated ischemic OCNPs against matched controls on the subsequent development of stroke with at least two years of follow up. Case reports and series were excluded. Appropriate studies were entered for meta-analysis to determine hazard ratios. Search and data extraction was completed on 22 Feb 2021. Random effect models were used to generate pooled hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Three studies were suitable for meta-analysis (total n = 2,756 OCNP cases and 21,239 matched controls). The meta-analysis demonstrated a hazard ratio of 5.96 (4.20-8.46 95% CI) of subsequent stroke after isolated OCNP within the first year. The hazard ratio reduced to 3.27 (2.61-4.10 95% CI) after five years although remains raised at 2.49 (1.53-4.06 95% CI) up to 12 years. The highest risk was demonstrated with 3rd cranial nerve palsies. Two additional studies assessed the risk of stroke with newly diagnosed diabetics and compared OCNPs against lacunar stroke. These studies did not demonstrate a significant increased risk of stroke, although they may be statistically underpowered.

CONCLUSION

Ischemic OCNPs represent a significant risk factor for development of subsequent stroke in a similar magnitude to transient ischemic attack within the first year.

ABCD3-I and ABCD2 Scores in a TIA Population with Low Stroke Risk

Objectives

We aimed to evaluate the ABCD3-I score and compare it with the ABCD2 score in short- (1 week) and long-term (3 months; 1 year) stroke risk prediction in our post-TIA stroke risk study, MIDNOR TIA.

Materials and Methods

We performed a prospective, multicenter study in Central Norway from 2012 to 2015, enrolling 577 patients with TIA. In a subset of patients with complete data for both scores (n = 305), we calculated the AUC statistics of the ABCD3-I score and compared this with the ABCD2 score. A telephone follow-up and registry data were used for assessing stroke occurrence.

Results

Within 1 week, 3 months, and 1 year, 1.0% (n = 3), 3.3% (n = 10), and 5.2% (n = 16) experienced a stroke, respectively. The AUCs for the ABCD3-I score were 0.72 (95% CI, 0.54 to 0.89) at 1 week, 0.66 (95% CI, 0.53 to 0.80) at 3 months, and 0.68 (0.95% CI, 0.56 to 0.79) at 1 year. The corresponding AUCs for the ABCD2 score were 0.55 (95% CI, 0.24 to 0.86), 0.55 (95% CI, 0.42 to 0.68), and 0.63 (95% CI, 0.50 to 0.76).

Conclusions

The ABCD3-I score had limited value in a short-term prediction of subsequent stroke after TIA and did not reliably discriminate between low- and high-risk patients in a long-term follow-up. The ABCD2 score did not predict subsequent stroke accurately at any time point. Since there is a generally lower stroke risk after TIA during the last years, the benefit of these clinical risk scores and their role in TIA management seems limited. Clinical Trial Registration. This trial is registered with NCT02038725 (retrospectively registered, January 16, 2014).

Comparison of Prediction Models based on Risk Factors and Retinal Characteristics Associated with Recurrence One Year after Ischemic Stroke

OBJECTIVES

To develop risk estimation models for 1-year ischemic stroke recurrence using clinical risk factors and retinal characteristics.

METHODS

From June 2017 to January 2019, 332 patients with first-ever ischemic stroke were enrolled and followed up in the Shenzhen Traditional Chinese Medicine hospital in China. The primary endpoint was defined as fatal or recurrent stroke after 1 year of the index stroke. Clinical risk factors and retinal characteristics were identified by multivariate logistic models.

RESULTS

The multivariate logistic model with only clinical risk factors showed that Cerebral Atherosclerosis (OR 1.68, 95%CI: 1.000-2.81), white matter lesions (OR 3.61, 95%CI: 2.18-5.98), and Cardiac disease (OR 1.88, 95%CI: 1.02-3.46) were statistically significantly associated with higher stroke recurrence risk. The sensitivity and specificity of this model were 69.1% and 68.4% respectively. The multivariate logistic model with only retinal characteristics showed that central retinal venule equivalent (OR .34, 95%CI: .14-.83), hemorrhage (OR .6, 95%CI: .41-.88), exudate (OR 1.64, 95%CI: 1.16-2.32), central retinal artery equivalent (OR 2.95, 95%CI: 1.23-7.08), and Aangle (OR 0.8, 95%CI: .61-1.004) were statistically significantly associated with stroke recurrence. The sensitivity and specificity of the model were 62.0% and 64.4% respectively. The multivariate logistic model with both clinical risk factors and retinal characteristics showed that cerebral atherosclerosis (OR 1.74, 95%CI: 1.020-2.981), white matter lesions (OR 3.65, 95%CI: 2.17-6.13), cardiac disease (OR 1.99, 95%CI: 1.06-3.74), hemorrhage (OR .68, 95%CI: .49-.96), exudate (OR 1.65, 95%CI: 1.16-2.36) were independent risk factors of stroke recurrence. The sensitivity and specificity of the model were 72.5% and 70.7% respectively.

CONCLUSIONS

Combining the traditional risk factors of stroke with the retinal vessels characteristics to establish the recurrent cerebral infarction prediction model may improve the accuracy of the prediction.

Risk Stratification of Older Adults Who Present to the Emergency Department With Syncope: The FAINT Score

STUDY OBJECTIVE

Older adults with syncope are commonly treated in the emergency department (ED). We seek to derive a novel risk-stratification tool to predict 30-day serious cardiac outcomes.

METHODS

We performed a prospective, observational study of older adults (≥60 years) with unexplained syncope or near syncope who presented to 11 EDs in the United States. Patients with a serious diagnosis identified in the ED were excluded. We collected clinical and laboratory data on all patients. Our primary outcome was 30-day all-cause mortality or serious cardiac outcome.

RESULTS

We enrolled 3,177 older adults with unexplained syncope or near syncope between April 2013 and September 2016. Mean age was 73 years (SD 9.0 years). The incidence of the primary outcome was 5.7% (95% confidence interval [CI] 4.9% to 6.5%). Using Bayesian logistic regression, we derived the FAINT score: history of heart failure, history of cardiac arrhythmia, initial abnormal ECG result, elevated pro B-type natriuretic peptide, and elevated high-sensitivity troponin T. A FAINT score of 0 versus greater than or equal to 1 had sensitivity of 96.7% (95% CI 92.9% to 98.8%) and specificity 22.2% (95% CI 20.7% to 23.8%), respectively. The FAINT score tended to be more accurate than unstructured physician judgment: area under the curve 0.704 (95% CI 0.669 to 0.739) versus 0.630 (95% CI 0.589 to 0.670).

CONCLUSION

Among older adults with syncope or near syncope of potential cardiac cause, a FAINT score of zero had a reasonably high sensitivity for excluding death and serious cardiac outcomes at 30 days. If externally validated, this tool could improve resource use for this common condition.

Meta-Regression to Identify Patients Deriving the Greatest Benefit from Dual Antiplatelet Therapy after Stroke or Transient Ischemic Attack Without Thrombolytic or Thrombectomy Treatment

The patient's profile drawing the greatest benefit from dual antiplatelet therapy (DAPT) after a noncardioembolic, ischemic cerebrovascular event is not well characterized. Aim of this metaregression analysis was to compare DAPT versus single antiplatelet therapy (SAPT) in patients with stroke or transient ischemic attack (TIA). We searched randomized trials evaluating clinical outcome with aspirin plus a P₂Y₁₂ inhibitor versus SAPT in patients with noncardioembolic stroke or TIA. Primary end point was the incidence of recurrent stroke; safety outcome measure was major bleeding. Eleven trials were included in the analysis, enrolling 24,175 patients treated with DAPT (aspirin plus clopidogrel, n = 12,074) or SAPT (n = 12,101) after a stroke or TIA event. In the DAPT group the rates of recurrent stroke were lower (7.1% vs 8.8% with SAPT; odds ratios [OR] 0.74, 95% confidence interval 0.62 to 0.88; p = 0.0007) and the incidence of major bleeding was twofold higher (OR 2.01, 1.35 to 3.01; p = 0.0006). Metaregression indicated a positive correlation between prevention of recurrent stroke by DAPT and baseline stroke severity (p = 0.019), baseline risk profile (p = 0.0001), or prevalence of carotid atherosclerosis (p = 0.040). DAPT was more effective when initiated ≤7 days (OR 0.67, 0.58 to 0.77; p < 0.00001) and used for ≤3 months (OR 0.66, 0.58 to 0.76; p < 0.00001) after the event. In conclusion, in patients with stroke or TIA, the highest benefit of DAPT was observed in patients with higher baseline risk profile, greater stroke severity, or concomitant carotid disease, and when DAPT was initiated early and given for ≤3 months.

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.

Recent advances in the management of transient ischemic attacks

Significant advances in our understanding of transient ischemic attack (TIA) have taken place since it was first recognized as a major risk factor for stroke during the late 1950's. Recently, numerous studies have consistently shown that patients who have experienced a TIA constitute a heterogeneous population, with multiple causative factors as well as an average 5-10% risk of suffering a stroke during the 30 days that follow the index event. These two attributes have driven the most important changes in the management of TIA patients over the last decade, with particular attention paid to effective stroke risk stratification, efficient and comprehensive diagnostic assessment, and a sound therapeutic approach, destined to reduce the risk of subsequent ischemic stroke. This review is an outline of these changes, including a discussion of their advantages and disadvantages, and references to how new trends are likely to influence the future care of these patients.

Incidence, predictors, and etiology of subsequent ischemic stroke within one year after transient ischemic attack

Background Incidence and predictors of ischemic stroke in patients with transient ischemic attack (TIA) have not been fully clarified outside Europe and North America. Aims We undertook the present prospective, multicenter study to clarify the incidence, predictors, and etiology of ischemic stroke within one year of TIA onset in Japan. Methods The study subjects were patients within seven days of TIA onset who were enrolled in a prospective register from 57 hospitals between June 2011 and December 2013. The primary endpoint was occurrence of ischemic stroke. Results Of 1365 consecutive patients, 1245 were followed for one year after TIA onset; 101 (8.1%) experienced ischemic stroke during follow-up. The leading subtype of ischemic stroke was small-vessel occlusion (SVO) followed by large-artery atherosclerosis (LAA) attributable to intracranial artery diseases. When dividing ischemic stroke events between those occurring within the first 90 days after TIA onset and those occurring after the first 90 days, the leading subtype of ischemic stroke within the first 90 days after TIA onset was SVO, followed by LAA attributable to intracranial artery diseases. In comparison, the subtypes most commonly seen beyond the first 90 days after TIA onset were cardioembolic and LAA attributable to intracranial artery disease. The one-year risk of ischemic stroke increased significantly as ABCD² score increased, at 6.2% for 0-3 points, 7.2% for 4-5 points, and 11.6% for 6-7 points. Conclusions The one-year ischemic stroke risk after TIA was about 8% and was associated with the ABCD² score. The most common subtype of subsequent ischemic stroke was SVO.

The determination of copeptin levels helps management decisions among transient ischaemic attack patients

BACKGROUND

Most approaches to transient ischaemic attack (TIA) triage use clinical scores and vascular imaging; however, some biomarkers have been suggested to improve the prognosis of TIA patients.

METHODS

Serum levels of copeptin, adiponectin, neopterin, neuron-specific enolase, high-sensitivity C-reactive protein, IL-6, N-terminal pro-B-type natriuretic peptide, S100β, tumour necrosis factor-alpha and IL-1α as well as clinical characteristics were assessed on consecutive TIA patients during the first 24 h of the onset of symptoms.

RESULTS

Among 237 consecutive TIA patients, 12 patients (5%) had a stroke within 7 days and 15 (6%) within 90 days. Among all candidate biomarkers analysed, only copeptin was significantly increased in patients with stroke recurrence (SR) within 7 days (P = 0.026) but not within 90 days. A cut-off point of 13.8 pmol/l was established with a great predictive negative value (97.4%). Large artery atherosclerosis (LAA) [hazard ratio (HR) 12.7, 95% CI 3.2-50.1, P < 0.001] and copeptin levels ≥13.8 pmol/l (HR 3.9, 95% CI 1.01-14.4, P = 0.039) were independent predictors of SR at the 7-day follow-up. LAA was the only predictor of 90-day SR (HR 7.4, 95% CI 2.5-21.6, P < 0.001). ABCD3I was associated with 7- and 90-day SRs (P = 0.025 and P = 0.034, respectively). The association between copeptin levels and LAA had a diagnostic accuracy of 90.3%.

CONCLUSIONS

Serum copeptin could be an important prognostic biomarker to guide management decisions among TIA patients. Therefore, TIA patients with copeptin levels below 13.8 pmol/l and without LAA have an insignificant risk of 7-day SR and could be managed on an outpatient basis.

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.

Diabetes is an Independent Risk Factor for Stroke Recurrence in Stroke Patients: A Meta-analysis

BACKGROUND

This study aimed to assess the association between diabetes and risk of stroke recurrence (especially ischemic stroke recurrence) and to evaluate whether diabetes was an independent predictor for stroke recurrence in stroke patients with diabetes.

METHODS

The relevant studies were identified through searching databases of PubMed, EMBASE, and Cochrane library. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled to evaluate the association between diabetes and risk of stroke recurrence. Funnel plot and Egger's regression tests were used to assess publication bias. All statistical analyses were conducted in Stata 12.0.

RESULTS

Eighteen studies containing totally 43,899 participants were included in the meta-analysis. The results showed that stroke recurrence risk of all stroke patients with diabetes was significantly higher than those without diabetes (HR, 1.45; 95% CI, 1.32-1.59), similar results were achieved in ischemic stroke patients (HR, 1.44; 95% CI, 1.28-1.61), and there were no regional differences (Europe: HR, 1.28; 95% CI, 1.13-1.44; USA: HR, 1.89; 95% CI, 1.53-2.33; Asia: HR, 1.57, 95% CI, 1.28-1.92, respectively) and age differences (mean age <70 years: HR, 1.58; 95% CI, 1.34-1.86; mean age ≥70 years: HR, 1.27; 95% CI, 1.11-1.45, respectively). The heterogeneity of all included studies was not statistically significant, and no publication bias was observed.

CONCLUSIONS

This meta-analysis shows that diabetes is an independent risk factor for stroke recurrence in stroke patients.

Long-term disability after lacunar stroke: secondary prevention of small subcortical strokes

OBJECTIVES

To determine whether vascular and demographic factors predict worsening disability up to 8 years after lacunar stroke.

METHODS

SPS3 (Secondary Prevention of Small Subcortical Strokes) was a clinical trial in lacunar stroke patients with annual assessment of disability using the Older Americans Resources and Survey instrumental activities of daily living (IADL) scale (range 0-14). Generalized estimating equations modeled the likelihood of disability (IADL <14) over time, adjusting for demographics, medical risk factors, cognition, mood, stroke location, and geographic region in univariate and multivariable models. IADL assessments after recurrent stroke were censored. We stratified by study region and age quartile.

RESULTS

Among 2,820 participants, mean age was 63.4 years (SD 10.8), 63% were male, 36% had diabetes, 90% hypertension, and 10% prior stroke. Mean follow-up was 3.7 years. In multivariable models, female sex, education, diabetes, nonregular alcohol use, prior stroke, Cognitive Abilities Screening Instrument score, depression, mild cognitive impairment, and stroke location were associated with disability. The youngest age quartile had decreased odds of disability over time (odds ratio 0.90 per year, 95% confidence interval 0.85-0.95), whereas the oldest age quartile had increased odds (2.20, 95% confidence interval 1.75-2.75). Americans and Latin Americans had >2-fold greater odds of disability per year compared with Spaniards (p < 0.0001).

CONCLUSIONS

In lacunar stroke patients, older age was associated with worsening long-term disability, even without recurrence. Worse long-term function was associated with diabetes, cognitive status, and prior stroke, and regional differences may be attributable to variations in health care delivery or scale interpretation.

Canadian Stroke Best Practice Recommendations: Secondary Prevention of Stroke Guidelines, Update 2014

Every year, approximately 62 000 people with stroke and transient ischemic attack are treated in Canadian hospitals. The 2014 update of the Canadian Secondary Prevention of Stroke guideline is a comprehensive summary of current evidence-based recommendations for clinicians in a range of settings, who provide care to patients following stroke. Notable changes in this 5th edition include an emphasis on treating the highest risk patients who present within 48 h of symptom onset with transient or persistent motor or speech symptoms, who need to be transported to the closest emergency department with capacity for advanced stroke care; a recommendation for brain and vascular imaging (of the intra- and extracranial vessels) to be completed urgently using computed tomography/computed tomography angiography; prolonged cardiac monitoring for patients with suspective cardioembolic stroke but without evidence for atrial fibrillation on electrocardiogram or holter monitoring; and de-emphasizing the need for routine echocardiogram. The Canadian Stroke Best Practice Recommendations include a range of supporting materials such as implementation resources to facilitate the adoption of evidence to practice, and related performance measures to enable monitoring of uptake and effectiveness of the recommendations using a standardized approach. The guidelines further emphasize the need for a systems approach to stroke care, involving an interprofessional team, with access to specialists regardless of patient location, and the need to overcome geographical barriers to ensure equity in access within a universal health-care system.

An assessment of the cost-effectiveness of magnetic resonance, including diffusion-weighted imaging, in patients with transient ischaemic attack and minor stroke: a systematic review, meta-analysis and economic evaluation

BACKGROUND

Patients with transient ischaemic attack (TIA) or minor stroke need rapid treatment of risk factors to prevent recurrent stroke. ABCD2 score or magnetic resonance diffusion-weighted brain imaging (MR DWI) may help assessment and treatment.

OBJECTIVES

Is MR with DWI cost-effective in stroke prevention compared with computed tomography (CT) brain scanning in all patients, in specific subgroups or as 'one-stop' brain-carotid imaging? What is the current UK availability of services for stroke prevention?

DATA SOURCES

Published literature; stroke registries, audit and randomised clinical trials; national databases; survey of UK clinical and imaging services for stroke; expert opinion.

REVIEW METHODS

Systematic reviews and meta-analyses of published/unpublished data. Decision-analytic model of stroke prevention including on a 20-year time horizon including nine representative imaging scenarios.

RESULTS

The pooled recurrent stroke rate after TIA (53 studies, 30,558 patients) is 5.2% [95% confidence interval (CI) 3.9% to 5.9%] by 7 days, and 6.7% (5.2% to 8.7%) at 90 days. ABCD2 score does not identify patients with key stroke causes or identify mimics: 66% of specialist-diagnosed true TIAs and 35-41% of mimics had an ABCD2 score of ≥ 4; 20% of true TIAs with ABCD2 score of < 4 had key risk factors. MR DWI (45 studies, 9078 patients) showed an acute ischaemic lesion in 34.3% (95% CI 30.5% to 38.4%) of TIA, 69% of minor stroke patients, i.e. two-thirds of TIA patients are DWI negative. TIA mimics (16 studies, 14,542 patients) make up 40-45% of patients attending clinics. UK survey (45% response) showed most secondary prevention started prior to clinic, 85% of primary brain imaging was same-day CT; 51-54% of patients had MR, mostly additional to CT, on average 1 week later; 55% omitted blood-sensitive MR sequences. Compared with 'CT scan all patients' MR was more expensive and no more cost-effective, except for patients presenting at > 1 week after symptoms to diagnose haemorrhage; strategies that triaged patients with low ABCD2 scores for slow investigation or treated DWI-negative patients as non-TIA/minor stroke prevented fewer strokes and increased costs. 'One-stop' CT/MR angiographic-plus-brain imaging was not cost-effective.

LIMITATIONS

Data on sensitivity/specificity of MR in TIA/minor stroke, stroke costs, prognosis of TIA mimics and accuracy of ABCD2 score by non-specialists are sparse or absent; all analysis had substantial heterogeneity.

CONCLUSIONS

Magnetic resonance with DWI is not cost-effective for secondary stroke prevention. MR was most helpful in patients presenting at > 1 week after symptoms if blood-sensitive sequences were used. ABCD2 score is unlikely to facilitate patient triage by non-stroke specialists. Rapid specialist assessment, CT brain scanning and identification of serious underlying stroke causes is the most cost-effective stroke prevention strategy.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Metabolomics predicts stroke recurrence after transient ischemic attack

OBJECTIVE

To discover, by using metabolomics, novel candidate biomarkers for stroke recurrence (SR) with a higher prediction power than present ones.

METHODS

Metabolomic analysis was performed by liquid chromatography coupled to mass spectrometry in plasma samples from an initial cohort of 131 TIA patients recruited <24 hours after the onset of symptoms. Pattern analysis and metabolomic profiling, performed by multivariate statistics, disclosed specific SR and large-artery atherosclerosis (LAA) biomarkers. The use of these methods in an independent cohort (162 subjects) confirmed the results obtained in the first cohort.

RESULTS

Metabolomics analyses could predict SR using pattern recognition methods. Low concentrations of a specific lysophosphatidylcholine (LysoPC[16:0]) were significantly associated with SR. Moreover, LysoPC(20:4) also arose as a potential SR biomarker, increasing the prediction power of age, blood pressure, clinical features, duration of symptoms, and diabetes scale (ABCD2) and LAA. Individuals who present early (<3 months) recurrence have a specific metabolomic pattern, differing from non-SR and late SR subjects. Finally, a potential LAA biomarker, LysoPC(22:6), was also described.

CONCLUSIONS

The use of metabolomics in SR biomarker research improves the predictive power of conventional predictors such as ABCD2 and LAA. Moreover, pattern recognition methods allow us to discriminate not only SR patients but also early and late SR cases.

Prediction of recurrent stroke with ABCD2 and ABCD3 scores in patients with symptomatic 50-99% carotid stenosis

BACKGROUND

Although it is preferable that all patients with a recent Transient Ischemic Attack (TIA) undergo acute carotid imaging, there are centers with limited access to such acute examinations. It is controversial whether ABCD2 or ABCD3 scores can be used to triage patients to acute or delayed carotid imaging. It would be acceptable that some patients with a symptomatic carotid stenosis are detected with a slight delay as long as those who will suffer an early recurrent stroke are detected within 24 hours. The aim of this study is to analyze the ability of ABCD2 and ABCD3 scores to predict ipsilateral ischemic stroke among patients with symptomatic 50-99% carotid stenosis.

METHODS

In this secondary analysis of the ANSYSCAP-study, we included 230 consecutive patients with symptomatic 50-99% carotid stenosis. We analyzed the risk of recurrent ipsilateral ischemic stroke before carotid endarterectomy based on each parameter of the ABCD2 and ABCD3 scores separately, and for total ABCD2 and ABCD3 scores. We used Kaplan-Meier analysis.

RESULTS

None of the parameters in the ABCD2 or ABCD3 scores could alone predict all 12 of the ipsilateral ischemic strokes that occurred within 2 days of the presenting event, but clinical presentation tended to be a statistically significant risk factor for recurrent ipsilateral ischemic stroke (p = 0.06, log rank test). An ABCD2 score ≥2 and an ABCD3 score ≥4 could predict all 12 of these strokes as well as all 25 ipsilateral ischemic strokes that occurred within 14 days. To use ABCD3 score seems preferable over the ABCD2 score because a higher proportion of low risk patients were identified (17% of the patients had an ABCD3 score <4 while only 6% had an ABCD2 < 2).

CONCLUSIONS

Although it is preferable that carotid imaging be performed within 24 hours, our data support that an ABCD3 score ≥4 might be used for triaging patients to acute carotid imaging in clinical settings with limited access to carotid imaging. However, our findings should be validated in a larger cohort study.

[Prediction in cerebrovascular diseases]

Prediction of the outcome of cerebrovascular diseases or of the effects and complications of various forms of treatment are essential components of all stroke treatment regimens. This review focuses on the prediction of the stroke risk in primary prevention, the prediction of the risk of secondary stroke following a transient ischemic attack (TIA), the estimation of the outcome following manifest stroke and the treatment effects, the prediction of secondary cerebrovascular events and the prediction of vascular cognitive impairment following stroke. All predictive activities in cerebrovascular disease are hindered by the translation of predictive results from studies and patient populations to the individual patient. Future efforts in genetic analyses may be able to overcome this barrier and to enable individual prediction in the area of so-called personalized medicine. In all the various fields of prediction in cerebrovascular diseases, three major variables are always important: age of the patient, severity and subtype of the stroke. Increasing age, more severe stroke symptoms and the cardioembolic stroke subtype predict a poor outcome regarding both survival and permanent disability. This finding is somewhat banal and will therefore never replace the well experienced clinician judging the chances of a patient and taking into account the personal situation of this patient, e.g. for initiation of a rehabilitation program. Besides the individualized prediction, in times of restricted economic resources and increasing tendency to clarify questions of medical treatment in court, it seems unavoidable to use prediction in economic and medicolegal interaction with clinical medicine. This tendency will be accompanied by difficult ethical problems which neurologists must be aware of. Improved prediction should not be used to allocate or restrict resources or to restrict medically indicated treatment.

How predictors and patterns of stroke recurrence after a TIA differ during the first year of follow-up

The highest risk of subsequent stroke after a TIA occurs within the first week after the index event. However, the risk of stroke recurrence (SR) remains high during the first year of follow-up. We studied the temporal pattern and predictors of SR (at 7 days and from 7 days to 1-year follow-up). Between April 2008 and December 2009, we included 1,255 consecutive TIA patients from 30 Spanish stroke centers (PROMAPA study). We determined the short-term (at 7 days) and long-term (from 8 days to 1 year) risk of SR. Patients who underwent short-term recurrence and long-term recurrence were compared with regard to clinical findings, vascular territories, and etiology. Enough information (clinical variables and extracranial vascular imaging) was assessed in 1,137 (90.6 %) patients. The 7-day stroke risk was 2.6 %. 32 (3.0 %) patients had an SR after 7-day follow-up. Multiple TIA (HR 3.50, 1.67-7.35, p = 0.001) and large artery atherosclerosis (HR 2.51, 1.17-5.37, p = 0.018) were independent predictors of early SR, whereas previous stroke (HR 1.40, 1.03-1.92, p = 0.034) and coronary heart disease (2.65, 1.28-5.50, p = 0.009) were independent predictors of late SR. Notoriously, 80 % of SR happened in the same territory of the index TIA at 7-day follow-up, whereas only 38 % during the long-term follow-up (p < 0.001). Different predictors of SR were identified throughout the follow-up period. Moreover, the ischemic mechanism differed in early and late stroke recurrences.

Long-term risk of stroke after transient ischaemic attack: a hospital-based validation of the ABCD² rule

BACKGROUND

The ABCD2 clinical prediction rule is a seven point summation of clinical factors independently predictive of stroke risk. The purpose of this cohort study is to validate the ABCD2 rule in a Bulgarian hospital up to three years after TIA.

METHODS

All consecutive admissions to an emergency department with symptoms of a first TIA were included. Baseline data and clinical examinations including the ABCD2 scores were documented by neurologists. Discrimination and calibration performance was examined using ABCD2 cut-off scores of ≥3, ≥4 and ≥5 points, consistent with the international guidelines. The Hosmer-Lemeshow test was used to examine calibration between the observed and expected outcomes as predicted by ABCD2 score within the logistic regression analysis.

RESULTS

Eighty-nine patients were enrolled to the study with a mean age of 63 years (+/- 12 years). Fifty-nine percent (n = 53) of the study population was male. Seven strokes (7.8%) occurred within the first year and six further strokes within the three-year follow-up period. There was no incident of stroke within the first 90 days after TIA. The rule demonstrated good predictive (OR = 1.58, 95% CI 1.09-2.29) and discriminative performance (AUCROC = 0.72, 95% CI 0.58-0.86), as well as a moderate calibration performance at three years.

CONCLUSION

This validation of the ABCD2 rule in a Bulgarian hospital demonstrates that the rule has good predictive and discriminative performance at three years. The ABCD2 is quick to administer and may serve as a useful tool to assist clinicians in the long-term management of individuals with TIA.

ABCD2 score and BNP level in patients with TIA and cerebral stroke

Scoring systems have been designed to help physicians in early prediction of cerebral stroke following Transitional Ischemic Attack (TIA). ABCD2 system is one of these scoring systems. Considering increase of brain natriuretic peptide following cerebral ischemic stroke, BNP level may be associated with incidence of ischemic stroke following TIA. The present study evaluates ABCD2 score, BNP level in patients with TIA and incidence of cerebral stroke. This cross sectional-analytical study evaluated 78 patients with TIA. ABCD2 score was calculated for all patients based on some criteria including age, blood pressure, clinical manifestations (speech/motor disorder), symptoms duration and diabetes. BNP level was measured at the reference laboratory when the patient referred to the treatment center. The patients were followed up for 6 months considering incidence of cerebral stroke and TIA. Mean age of the patients was 66.53 +/- 13.08 years and the sample was consisted of 62.8% male and 37.2% female patients. Mean BNP level and mean ABCD2 score was 611.31 +/- 125.61 and 4.61 +/- 10.99 in all patients, respectively. During follow-up period, TIA recurrence and cerebral stroke were, respectively seen in 11.5 and 3.8% of cases. Mortality was reported in 5.1% of the patients. BNP was significantly higher in cases with recursive TIA (p = 0.03). But, there was not any difference considering ABCD2 score (p = 0.38). BNP is capable of predicting TIA recurrence following first TIA and it can be used in this case.

Cost-Minimization Analysis of Computed Tomography versus Magnetic Resonance Imaging in the Evaluation of Patients with Transient Ischemic Attacks at a Large Academic Center

Background

The type of neuroimaging for the evaluation of transient ischemic attack (TIA) is debatable. Many patients undergo head computed tomography (CT) with or without CT angiogram (CTA) while being at the emergency department (ED) and later magnetic resonance imaging (MRI) with MR angiogram (MRA) during admission. We hypothesized that evaluation with only one imaging modality (CT/CTA or MRI/MRA) is sufficient to formulate a treatment plan. We looked for the most cost-effective way to evaluate TIA patients.

Methods

We performed a retrospective chart review of 82 patients with TIA. All patients had completely resolved neurological deficit at the time of their evaluation in the ED. We divided the patients into two groups. In group 1, the evaluation included CT with CTA of the head and neck. In group 2, the evaluation included brain MRI with MRA or CTA of the head and neck. We compared these two groups for clinical characteristics and etiological evaluations of stroke/TIA. The outcomes were measured by the number of therapeutic adjustments for the prevention of another ischemic stroke/TIA at the time of discharge from the hospital and revascularization procedures. We counted the following as therapeutic adjustment: (1) antiplatelet therapy was started de novo; (2) anticoagulation was started; (3) arterial revascularization procedure was performed, and (4) one antiplatelet agent was substituted for another. We performed a cost-effectiveness analysis if the outcomes of the two groups were different and a cost-minimization analysis if there was no difference in the outcomes. All cost calculations were made based on Medicare CPT codes.

Results

Group 1 included 23 patients and group 2 59 patients. The patients in both groups had similar demographic and clinical characteristics. There was no difference in other etiological evaluations in groups 1 and 2. All patients underwent head CT as the first tool of evaluation whether MRI was done later or not. Therapeutic adjustments and revascularization procedures did not differ between the two groups. All head CTs showed no acute changes. MRI showed small ischemic infarcts in 44% of the patients in group 2. The average per-patient cost of neuroimaging with CT/CTA was USD 1,460.00, with CT and MRI/MRA USD 1,569 and with CT/CTA and brain MRI USD 2,090.00 (p < 0.01).

Conclusion

Either MRI/MRA or CT/CTA might be sufficient for the evaluation of patients with TIA or small asymptomatic strokes. If head CT at the ED is bypassed, a brain MRI with MRA of the head and neck would be the most informative tool at the lowest cost. Prospective studies with larger numbers of patients are needed for a better understanding of the safety and cost of imaging tools used for patients with TIA.

Carotid artery stenting improves cerebral hemodynamics regardless of the flow direction of ophthalmic artery

We enrolled 221 patients with elective carotid artery stenting (CAS). Patients with contralateral carotid stenosis exceeding 50%, insufficient vertebral artery (VA) flows, or angioplasty at subclavian artery were excluded. All patients underwent serial cerebral ultrasound studies. Of the 116 included patients, the direction of ophthalmic artery (OA) flow was forward in 74 patients while reversed in 42. The reversed flow group had worse ipsilateral stenosis, higher hemoglobin, and cardiac output. After CAS, the reversed flow group had an immediate recovery of ipsilateral internal carotid artery flow volume (FV; P < .0001), time average velocity (TAV) of middle cerebral artery (P = .02), and normalization of OA flow. The forward flow group had gradual decrement in TAV of contralateral anterior cerebral artery (P = .01) and total FV of VA (P = .001). Our results suggest CAS improves cerebral hemodynamics through different ways regardless of the direction of OA flow.

Transient ischemic attacks: predictability of future ischemic stroke or transient ischemic attack events

The short-term risk of an ischemic stroke after a transient ischemic attack (TIA) is estimated to be approximately 3%–10% at 2 days, 5% at 7 days, and 9%–17% at 90 days, depending on active or passive ascertainment of ischemic stroke. Various risk prediction scores are available to identify high-risk patients. We present here a pragmatic review of the literature discussing the main scoring systems. We also provide the sensitivity, specificity, positive predictive value, and negative predictive value for each scoring system. Our review shows that scoring systems including brain imaging and vascular imaging are better at risk prediction than scores that do not include this information.

Risk of very early recurrent cerebrovascular events in symptomatic carotid artery stenosis

Object

The risk of recurrence of cerebrovascular events within the first 72 hours of admission in patients hospitalized with symptomatic carotid artery (CA) stenoses and the risks and benefits of emergency CA intervention within the first hours after the onset of symptoms are not well known. Therefore, the authors aimed to assess 1) the ipsilateral recurrence rate within 72 hours of admission, in the period from 72 hours to 7 days, and after 7 days in patients presenting with nondisabling stroke, transient ischemic attack (TIA), or amaurosis fugax (AF), and with an ipsilateral symptomatic CA stenosis of 50% or more, and 2) the risk of stroke in CA interventions within 48 hours of admission versus the risk in interventions performed after 48 hours.

Methods

Ninety-four patients were included in this study. These patients were admitted to hospital within 48 hours of a nondisabling stroke, TIA, or AF resulting from a symptomatic CA stenosis of 50% or more. The patients underwent carotid endarterectomy (85 patients) or CA stenting (9 patients). At baseline, the cardiovascular risk factors of the patients, the degree of symptomatic CA stenosis, and the type of secondary preventive treatment were assessed. The in-hospital recurrence rate of stroke, TIA, or AF ipsilateral to the symptomatic CA stenosis was determined for the first 72 hours after admission, from 72 hours to 7 days, and after 7 days. Procedure-related cerebrovascular events were also recorded.

Results

The median time from symptom onset to CA intervention was 5 days (interquartile range 3.00–9.25 days). Twenty-one patients (22.3%) underwent CA intervention within 48 hours after being admitted. Overall, 15 recurrent cerebrovascular events were observed in 12 patients (12.8%) in the period between admission and CA intervention: 3 strokes (2 strokes in progress and 1 stroke) (3.2%), 5 TIAs (5.3%), and 1 AF (1.1%) occurred within the first 72 hours (total 9.6%) of admission; 1 TIA (1.1%) occurred between 72 hours and 7 days, and 5 TIAs (5.3%) occurred after more than 7 days. The corresponding actuarial cerebrovascular recurrence rates were 11.4% (within 72 hours of admission), 2.4% (between 72 hours and 7 days), and 7.9% (after 7 days). Among baseline characteristics, no predictive factors for cerebrovascular recurrence were identified.

Procedure-related cerebrovascular events occurred at a rate of 4.3% (3 strokes and 1 TIA), and procedures performed within the first 48 hours and procedures performed after 48 hours had a similar frequency of these events (4.5% vs 4.1%, respectively; p = 0.896).

Conclusions

The in-hospital recurrence of cerebrovascular events was quite low, but all recurrent strokes occurred within 72 hours. The risk of stroke associated with a CA intervention performed within the first 48 hours was not increased compared with that for later interventions. This raises the question of the optimal timing of CA intervention in symptomatic CA stenosis. To answer this question, more data are needed, preferably from large randomized trials.

Diagnostic and prognostic value of multimodal MRI in transient ischemic attack

BACKGROUND

The clinical diagnosis of transient ischemic attack is highly subjective, and the risk prediction after transient ischemic attack using the clinical parameters still remains unsatisfactory.

AIMS

We aimed to investigate the diagnostic and prognostic value of multimodal magnetic resonance imaging in transient ischemic attack patients.

METHODS

We prospectively performed diffusion-weighted imaging, perfusion-weighted imaging, and intracranial and extracranial magnetic resonance angiogram within 72 h of symptom onset in 162 transient ischemic attack patients defined by the classical time-based definition. Follow-up diffusion-weighted imaging was obtained three-days later in patients who did not exhibit lesions on the initial diffusion-weighted imaging. The occurrence of clinical events (transient ischemic attack or stroke) three-months after the initial transient ischemic attack was recorded, and the ABCD2 and ABCD3-I scores were calculated. The clinical and imaging parameters were compared between patients with and without initial diffusion-weighted imaging lesion, clinical events, and follow-up diffusion-weighted imaging lesions.

RESULTS

Abnormalities were present on diffusion-weighted imaging, perfusion-weighted imaging, and magnetic resonance angiogram in 38·9%, 44·1%, and 51·9% of patients, respectively. Diffusion-weighted imaging plus perfusion-weighted imaging explained 64·8%, and the addition of magnetic resonance angiogram explained 74% of the transient ischemic attack symptoms. The initial diffusion-weighted imaging positivity was associated with longer time from symptom onset to magnetic resonance imaging examination (odds ratio, 1·039; 95% confidence interval, 1·008-1·071; P=0·013). On follow-up diffusion-weighted imaging, new lesions were found in 46·7% of the patients who initially showed normal diffusion-weighted imaging findings. Initial perfusion-weighted imaging abnormality predicted the appearance of follow-up diffusion-weighted imaging lesion (chi-square=7·774, P=0·005). During the three-months follow-up, 23 patients (14·2%) experienced subsequent transient ischemic attack (n=16) or stroke (n=7). Symptomatic magnetic resonance angiogram abnormality (odds ratio, 12·667; 95% confidence interval, 2·859-56·110; P=0·001) was the only independent factor associated with clinical events with a sensitivity of 91·3% and specificity of 54·7% (C statistics, 0·73). None with initially normal multimodal magnetic resonance imaging findings developed subsequent clinical events.

CONCLUSIONS

Approximately three-quarter of transient ischemic attack is associated with multimodal magnetic resonance imaging abnormality. Initial perfusion-weighted imaging abnormality predicts newly developed diffusion-weighted imaging lesions, and symptomatic magnetic resonance angiogram abnormality seems to be the most important predictor for subsequent clinical events. Multimodal magnetic resonance imaging appears to be useful in assessing transient ischemic attack and predicting outcome in these patients.

Frequent inaccuracies in ABCD2 scoring in non-stroke specialists' referrals to a daily Rapid Access Stroke Prevention service

The 'accuracy' of age, blood pressure, clinical features, duration and diabetes (ABCD(2)) scoring by non-stroke specialists referring patients to a daily Rapid Access Stroke Prevention (RASP) service is unclear, as is the accuracy of ABCD(2) scoring by trainee residents. In this prospective study, referrals were classified as 'confirmed TIAs' if the stroke specialist confirmed a clinical diagnosis of possible, probable or definite TIA, and 'non-TIAs' if patients had a TIA mimic or completed stroke. ABCD(2) scores from referring physicians were compared with scores by experienced stroke specialists and neurology/geriatric medicine residents at a daily RASP clinic; inter-observer agreement was examined. Data from 101 referrals were analysed (mean age=60.0years, 58% male). The median interval between referral and clinic assessment was 1day. Of 101 referrals, 52 (52%) were 'non-TIAs': 45 (86%) of 52 were 'TIA mimics' and 7 (14%) of 52 were completed strokes. There was only 'fair' agreement in total ABCD(2) scoring between referring physicians and stroke specialists (κ=0.37). Agreement was 'excellent' between residents and stroke specialists (κ=0.91). Twenty of 29 patients scored as 'moderate to high risk' (score 4-6) by stroke specialists were scored 'low risk' (score 0-3) by referring physicians. ABCD(2) scoring by referring doctors is frequently inaccurate, with a tendency to underestimate stroke risk. These findings emphasise the importance of urgent specialist assessment of suspected TIA patients, and that ABCD(2) scores by non-stroke specialists cannot be relied upon in isolation to risk-stratify patients. Inter-observer agreement in ABCD(2) scoring was 'excellent' between residents and stroke specialists, indicating short-term training may improve accuracy.

Predictive value of brain and vascular imaging including intracranial vessels in transient ischaemic attack patients: external validation of the ABCD3-I score

BACKGROUND AND PURPOSE

Recently, brain and vascular imaging have been added to clinical variables to identify patients with transient ischaemic attack (TIA) with a high risk of stroke recurrence. The aim of our study was to externally validate the ABCD3-I score and the same score taking into account intracranial circulation.

METHODS

We analyzed data from 1137 patients with TIA from the PROMAPA study who underwent diffusion-weighted magnetic resonance imaging (DWI) within 7 days of symptom onset. Clinical variables and diagnostic work-up were recorded prospectively. The end-points were subsequent stroke at 7 and 90 days follow-up.

RESULTS

A total of 463 (40.7%) subjects fulfilled all inclusion criteria. During follow-up, eight patients (1.7%) had a stroke within 7 days, and 14 (3.1%) had a stroke within 3 months. In the Cox proportional hazard multivariate analyses, the combination of large-artery atherosclerosis and positive DWI remained as independent predictors of stroke recurrence at 7- and 90-day follow-up [HR 8.23, 95% confidence interval (CI) 2.89-23.46, P < 0.001]. The ABCD3-I score was a powerful predictor of subsequent stroke. The area under the receiver operating characteristic curve was 0.83 (95% CI 0.72-0.93) at 7 days and 0.69 (95% CI 0.53-0.85) at 90 days. When we include intracranial vessel disease in the score, the area under the curve increases but the difference observed was non-significant.

CONCLUSION

The inclusion of vascular and neuroimaging information to clinical scales (ABCD3-I score) provides important prognostic information and also helps management decisions, although it cannot give a complete distinction between high-risk and low-risk groups.

Charlson comorbidity index in ischemic stroke and intracerebral hemorrhage as predictor of mortality and functional outcome after 6 months

BACKGROUND

The Charlson Comorbidity Index (CCI) is commonly used in outcome and mortality studies. Our aim was to investigate the association between CCI score and the functional outcome and mortality 6 months after ischemic stroke (IS) or intracerebral hemorrhage.

METHODS

This was a prospective observational cohort of patients with spontaneous intracerebral hemorrhage and IS admitted to the stroke unit during 18 months. The modified Rankin scale (mRS) score was obtained for subjects 6 months after event. The CCI score was dichotomized (low comorbidity 0 or 1 versus high ≥ 2) for analysis. The mRS score was also dichotomized (good outcome, mRS score 0 or 1 versus poor outcome, mRS score ≥ 2).

RESULTS

In all, 175 patients were enrolled in the study. Logistic regression showed that those with a high CCI score (≥ 2) had 37.3% increased odds of having a poor outcome (≥ 2) at 6 months and 68.4% greater odds of death at 6 months.

CONCLUSIONS

Comorbid medical conditions independently influence outcome after IS or intracerebral hemorrhage.