Incidence rates of first-ever ischemic stroke subtypes among blacks: a population-based study

Clinical relevance of reversible cerebral vasoconstriction syndrome in pregnant women with posterior reversible encephalopathy syndrome: review of case reports in Japan

We systematically reviewed case reports of posterior reversible encephalopathy syndrome (PRES), and investigated the characteristics of PRES in pregnant Japanese women and the clinical relevance of reversible cerebral vasoconstriction syndrome (RCVS) in pregnant women with PRES. Articles were collected using the PubMed/Medline and Ichushi-Web databases. This review was ultimately conducted on 121 articles (162 patients). The clinical characteristics of PRES, individual sites of PRES lesions, edema types, and clinical characteristics of RCVS in PRES cases were examined. The most common individual site of PRES lesion was the occipital lobe (83.3%), followed by the basal ganglia, parietal lobe, frontal lobe, brain stem, cerebellum, temporal lobe, thalamus, and splenium corpus callosum (47.5, 42.6, 24.7, 16.1, 9.3, 5.6, 4.3, and 0.0%, respectively). Edema types in 79 cases with PRES were mainly the vasogenic edema type (91.1%), with very few cases of the cytotoxic edema type (3.8%) and mixed type (5.1%). Among 25 PRES cases with RCVS, RCVS was not strongly suspected in 17 (68.0%) before magnetic resonance angiography. RCVS was observed at the same time as PRES in 13 cases (approximately 50%), and between days 1 and 14 after the onset of PRES in the other 12. These results suggest that the basal ganglia is a frequent site of PRES lesions in pregnant women. RCVS may occur at or after the onset of PRES, even if there are no symptoms to suggest RCVS.

FLAIR signal intensity ratio predicts small subcortical infarct early neurologic deterioration: a cross-sectional study

PURPOSE

Prior studies have used the fluid-attenuated inversion recovery sequence signal intensity ratio (FLAIR-SIR) to predict those with an incomplete infarct that may safely receive acute thrombolytics. Clinical early neurologic deterioration (END) of small subcortical infarcts (SSIs) is suspected to occur due to delayed infarct completion. We aimed to understand if a lower FLAIR-SIR, suggestive of an incomplete infarct, would have a higher likelihood of SSI-related END.

METHODS

A cross-sectional retrospective study was performed of those with an acute SSI (anterior or posterior circulation) without significant parent vessel steno-occlusive disease. END was defined as a new or worsened disabling neurologic deficit during the index hospitalization. Standard-of-care brain MRIs were reviewed from the hospitalization, and a FLAIR-SIR cutoff of ≤ 1.15 was used based on prior studies. Adjusted logistic regression models were used for analysis.

RESULTS

We identified 252 patients meeting inclusion criteria: median (IQR) age 68 (12) years, 38.5% (97/252) female, and 11% (28/252) with END. Tobacco use was more common in those without END (32%) compared with END (55%, p = 0.03). In adjusted analyses, a FLAIR-SIR cutoff of ≤ 1.15 yielded an odds ratio of 2.8 (95% CI 1.23-6.13, p = 0.012) of early neurological deterioration.

CONCLUSION

Those with a FLAIR-SIR ≤ 1.15 are nearly threefold more likely to develop SSI-related END.

The incidence of medium vessel occlusions: a population-based study

Introduction

The incidence of medium vessel occlusion (MeVO) is not well known. The objective of our study is to perform a population-based assessment to estimate the incidence of MeVOs.

Methods

Consecutive patients from Olmsted County, Minnesota who presented for acute ischemic stroke seen at Mayo Clinic Hospital from 1/1/2018 to 12/31/2020 who were found to have a MeVO were included in this study. MeVO was defined as occlusion at or beyond the level of the middle cerebral artery M2 segment, anterior cerebral artery A2 segment, posterior cerebral artery P1 segment, and cerebellar arteries. Census data for Olmsted County was obtained from the United States Census Bureau from the year 2020.

Results

A total of 1,718 patients were screened for the study, 77 patients fulfilled inclusion criteria to be included in the study. Presenting NIHSS was 9 (± 7). The population of Olmsted County was estimated to be 162,847. The incidence rate for MeVO was 16 cases (95% CI 12-19) per 100,000 people per year. Based on estimates of the US population in 2020 of 331,449,281 people, we estimate there are 52,236 (95% CI 40,635-64,002) new cases of MeVOs per year.

Conclusion

As the only stroke center in Olmsted County, we have been able to estimate the incidence of ischemic stroke due to MeVO. While the incidence of MeVOs is less than both large and small vessel occlusions, they still represent a significant proportion of strokes with significant morbidity and mortality that would benefit from further studies in both acute intervention and prevention.

Small-vessel disease in the brain

Cerebral small-vessels are generally located in the brain at branch points from major cerebral blood vessels and perfuse subcortical structures such as the white matter tracts, basal ganglia, thalamus, and pons. Cerebral small-vessel disease (CSVD) can lead to several different clinical manifestations including ischemic lacunar stroke, intracerebral hemorrhage, and vascular dementia. Risk factors for CSVD overlap with conventional vascular risk factors including hypertension, diabetes mellitus, and hypercholesterolemia, as well as genetic causes. As in cardiovascular disease, treatment of CSVD involves both primary and secondary prevention. Aspirin has not been established as a primary prevention strategy for CSVD among the general population; however, long-term antiplatelet therapy with aspirin alone continues to be the mainstay of secondary stroke prevention for non-cardioembolic ischemic stroke and high-risk TIA.

Evaluation of the Rapid Arterial oCclusion Evaluation (RACE) scale in Upstate South Carolina, USA

OBJECTIVES

Several stroke assessments have been designed for Emergency Medical Services to identify stroke patients with large vessel occlusion in the prehospital setting. The Rapid Arterial oCclusion Evaluation scale was developed in Spain, yet only few United States-based studies have confirmed findings from Spain. This study was designed to determine if the Rapid Arterial oCclusion Evaluation scale is a valid prehospital stroke assessment for identifying large vessel occlusion patients in South Carolina, USA.

MATERIALS AND METHODS

The performance of the Rapid Arterial oCclusion Evaluation scale was determined by calculating the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy at each score. The discriminative power of the Rapid Arterial oCclusion Evaluation score was evaluated using receiver operator characteristics. Comparison of the Rapid Arterial oCclusion Evaluation Scale to the National Institute of Health Stroke Scale was assessed using the Spearman's coefficient.

RESULTS

The Rapid Arterial oCclusion Evaluation scale had an acceptable discriminative power (c = 0.71). A score of ≥5 had a sensitivity of 0.71, specificity of 0.65, positive predictive value of 0.24, negative predictive value of 0.93, and accuracy of 0.66. There was a significant correlation between the Rapid Arterial Cclusion Evaluation score and the National Institute of Health Stroke Scale (rho = 0.60).

CONCLUSION

The Rapid Arterial oCclusion Evaluation scale performed comparably to the National Institute of Health Stroke Scale in South Carolina; however, performed lower than Spain. Future studies should investigate patient demographics and emergency medical services training to determine if these variables contribute to the results found in this study.

Clinical Utility of the Transthoracic Echocardiogram for Isolated Lacunar Infarcts: A Single-Center Experience

BACKGROUND

Stroke is a prominent and financially burdensome disease. Lacunar strokes are traditionally attributed to small vessel disease rather than cardioemboli, which typically occlude larger arteries. Thus, the benefit of screening for potential sources of cardioemboli in lacunar stroke patients is unclear. We evaluated the clinical utility of the transthoracic echocardiogram performed in patients with lacunar strokes.

METHODS

A single-center retrospective analysis of ischemic stroke patients from January 2013 through December 2017 was performed. Brain magnetic resonance imaging was used to select patients with a single lacunar infarct. Patients presenting with acute symptoms of cardiac disease or an abnormal electrocardiogram were excluded. Transthoracic echocardiogram results were reviewed, and their utility in decision-making was evaluated.

RESULTS

Of the 442 patients at our institution diagnosed with ischemic stroke during the inclusion period, 89 met inclusion criteria. Transthoracic echocardiogram detected a patent foramen ovale in 5.6% of patients, mitral annular calcification in 9.0% of patients, and abnormal wall motion in 4.5% of patients. For all patients, there were no findings that prompted anticoagulation, antibiotic, or surgical intervention. The cost of an inpatient transthoracic echocardiogram is $4100, resulting in $364,900 in unnecessary health care spending.

CONCLUSIONS

Transthoracic echocardiogram appears to have minimal therapeutic value in most patients with lacunar strokes. In stroke patients with no acute symptoms of cardiac disease and a normal electrocardiogram, it may be reasonable to forgo the transthoracic echocardiogram if the brain magnetic resonance imaging shows an isolated lacunar infarct.

Lacunar stroke: mechanisms and therapeutic implications

Lacunar stroke is a marker of cerebral small vessel disease and accounts for up to 25% of ischaemic stroke. In this narrative review, we provide an overview of potential lacunar stroke mechanisms and discuss therapeutic implications based on the underlying mechanism. For this paper, we reviewed the literature from important studies (randomised trials, exploratory comparative studies and case series) on lacunar stroke patients with a focus on more recent studies highlighting mechanisms and stroke prevention strategies in patients with lacunar stroke. These studies suggest that lacunar stroke is a heterogeneous disease with various mechanisms, including most commonly lipohyalinosis and less commonly atheromatous disease and cardioembolism, highlighting the importance of a careful review of brain and neurovascular imaging, a cardiac and systemic evaluation. A better understanding of pathomechanisms of neurological deterioration may lead to investigating the utility of novel treatment strategies and optimisation of short-term antithrombotic treatment strategies to reduce the risk of neurological deterioration and prevent long-term disability in patients with lacunar stroke.

Cryptogenic stroke: Contemporary trends, treatments, and outcomes in the United States

Background

Nationwide data on patients with cryptogenic stroke (CS) are lacking. We evaluated patient and hospital characteristics, in-hospital treatments, and discharge outcomes among patients with CS compared with other subtypes in the Get With The Guidelines (GWTG)-Stroke registry.

Methods

We identified patients with ischemic stroke (IS) admitted to GWTG-Stroke participating hospitals between January 1, 2016, and September 30, 2017, with documented National Institutes of Health Stroke Scale (NIHSS) scale and stroke etiology (cardioembolic [CE], large artery atherosclerosis [LAA], small vessel occlusion [SVO], other determined etiology [OTH], or CS). Using multivariable logistic regression, we compared hospital treatments and discharge outcomes by subtype, adjusted for patient and hospital characteristics.

Results

Among 316,623 patients from 1,687 hospitals, there were 63,301 (20.0%) patients with CS. In multivariable analysis, patients with CS received IV thrombolysis more often than other subtypes and had lower mortality than CE, LAA, and OTH but higher mortality than SVO. They were more likely to be discharged home than all other subtypes and be independent at discharge than LAA, OTH, or SVO.

Conclusions

In a large contemporary nationwide registry, CS accounted for 20% of ISs among patients with a documented stroke etiology. Patients with CS had a distinct profile of treatments and outcomes relative to other subtypes. Improved subtype documentation and further research into CS are warranted to improve care and outcomes for patients with stroke.

Time course of blood pressure control prior to lacunar TIA and stroke: Population-based study

OBJECTIVE

To determine the age-specific temporal trends in blood pressure (BP) before acute lacunar vs nonlacunar TIA and stroke.

METHODS

In a population-based study of TIA/ischemic stroke (Oxford Vascular Study), we studied 15-year premorbid BP readings from primary care records in patients with lacunar vs nonlacunar events (Trial of Org 10172 in Acute Stroke Treatment [TOAST]) stratified by age (<65, ≥65 years).

RESULTS

Of 2,085 patients (1,250 with stroke, 835 with TIA), 309 had lacunar events. In 493 patients <65 years of age, the prevalence of diagnosed hypertension did not differ between lacunar and nonlacunar events (46 [48.4%] vs 164 [41.2%], p = 0.20), but mean/SD premorbid BP (44,496 BP readings) was higher in patients with lacunar events (15-year records: systolic BP [SBP] 138.5/17.7 vs 133.3/15.0 mm Hg, p = 0.004; diastolic BP [DBP] 84.1/9.6 vs 80.9/8.4 mm Hg, p = 0.001), mainly because of higher mean BP during the 5 years before the event (SBP 142.6/18.8 vs 134.6/16.6 mm Hg, p = 0.0001; DBP 85.2/9.7 vs 80.6/9.0 mm Hg, p < 0.0001), with a rising trend (ptrend = 0.006) toward higher BP leading up to the event (<30-day pre-event SBP: 152.7/16.1 vs 135.3/23.1 mm Hg, p = 0.009; DBP 87.9/9.4 vs 80.8/12.8 mm Hg, p = 0.05; mean BP ≤1 year before the event 145.8/22.0 vs 134.7/16.1 mm Hg, p = 0.001; 86.1/10.7 vs 80.4/9.8 mm Hg, p = 0.0001). Maximum BP in the 5 years before the event was also higher in patients with lacunar events (SBP 173.7/26.6 vs 158.6/23.2 mm Hg, p = 0.0001; DBP 102.3/12.9 vs 94.2/11.2 mm Hg, p < 0.0001), as was persistently elevated BP (≥50% SBP >160 mm Hg, odd ratio 4.95, 95% confidence interval 1.99-12.31, p = 0.0002). However, no similar differences in BP were observed in patients ≥65 years of age.

CONCLUSION

Recent premorbid BP control is strongly temporarily related to acute lacunar events at younger ages, suggesting a direct role of BP in accelerating causal pathology and highlighting the need to control hypertension quickly.

Doppler sonographic assessment of carotid arteries in Sudanese stroke patients

BACKGROUND:

Hypertension, diabetes, and smoking were considered to be associated with several public health problems.

OBJECTIVE:

the study aims to explore the hemodynamic of carotid arteries in association with hypertension, diabetes, and smoking in Sudanese stroke patients.

MATERIALS AND METHODS:

In a quantitative descriptive study, fifty patients with stroke were scanned by B-mode and Doppler sonography. Carotid arteries were investigated with a 7-MHz linear transducer by a standard carotid sonography protocol.

RESULTS:

The average Doppler resistive index (RI) was 0.71 ± 0.084 and intima-media thickness was 1.39 ± 0.78 mm. The end diastolic velocities (EDVs) and peak systolic velocities (PSVs) of common carotid arteries were significantly changed in smokers and hypertensive (P < 0.05). The elevation of RI in right and left CCAs were significantly correlated with smokers (P = 0.017 and 0.010 respectively). Hemorrhagic stroke was most prevalent in hypertensive rather than diabetic and smokers. The carotid hemodynamics changed significantly in hypertensive and smokers more than diabetics.

CONCLUSION:

EDV and PSV were significantly correlated with hypertension and tobacco smoking rather than diabetes. Hypertension, diabetes, and smoking have an association with stroke and hand significant effect on carotid artery hemodynamic and atherosclerotic disease. The Doppler RIs were significantly correlated with smokers. Patients with risk factors of stroke should be scanned with Doppler sonography as early as possible.

Greater Risk of Stroke of Undetermined Etiology in a Contemporary HIV-Infected Cohort Compared with Uninfected Individuals

BACKGROUND

Although ischemic stroke risk is increased among people living with HIV infection, little is known about the epidemiology of ischemic stroke subtypes in contemporary HIV-infected cohorts. We examined the distribution of ischemic stroke subtypes among predominantly treated HIV-infected individuals to determine if and how the distribution differs from that of the general population.

METHODS

We studied 60 HIV-infected and 60 HIV-uninfected adults with a history of first-ever ischemic stroke between 2000 and 2012. Ischemic strokes were classified as 1 of 5 subtypes based on established criteria. We used multinomial logistic regression models to compare the relative frequency of ischemic stroke subtypes by HIV status.

RESULTS

Large artery atherosclerosis (23%) and stroke of undetermined etiology (23%) were the most common stroke subtypes among HIV-infected individuals. The most recent plasma HIV viral load before the stroke event differed by subtype, with a median undetectable viral load for individuals with large artery stroke and stroke of undetermined etiology. Using cardioembolic stroke as the reference subtype, HIV-infected individuals were at higher proportional risk of stroke of undetermined etiology compared with uninfected individuals (relative risk ratio [RRR]: 8.6, 95% confidence interval [CI]: 1.2-63.7, P = .04). Among HIV-infected individuals with virologically suppressed infection, we observed a trend toward a greater proportion of strokes attributable to large artery atherosclerosis (RRR: 6.7, 95% CI: .8-57.9, P = .08).

CONCLUSIONS

HIV-infected individuals may be at greater proportional risk of stroke of undetermined etiology compared with uninfected individuals. Further investigation is warranted to confirm this finding and determine underlying reasons for this greater risk.

Ethnic Comparison of Clinical Characteristics and Ischemic Stroke Subtypes Among Young Adult Patients With Stroke in Hawaii

BACKGROUND AND PURPOSE

Native Hawaiians and other Pacific Islanders (NHOPI) with ischemic stroke have younger age of stroke onset compared with whites. However, ethnic differences in stroke subtypes in this population have been inadequately studied.

METHODS

Consecutive young adult patients (aged ≤55 years) who were hospitalized for ischemic stroke between 2006 and 2012 at a tertiary center in Honolulu were studied. Clinical characteristics and stroke subtypes based on pathophysiological TOAST classification (Trial of Org 10172) of NHOPI and Asians were compared with whites.

RESULTS

A total of 427 consecutive young adult (mean age, 46.7±7.8 years) patients (NHOPI 45%, Asians 38%, and whites 17%) were studied. NHOPI had a higher prevalence of hypertension, diabetes mellitus, prosthetic valve, higher body mass index, hemoglobin A1c, and lower high-density lipoprotein than whites (all P<0.05). Stroke subtype distribution was not different between the ethnic groups. Specifically, the prevalence of small-vessel disease was similar between NHOPI (26.6%), whites (28.4%), and Asians (24.8%). In the univariate analyses, the use of intravenous tissue-type plasminogen activator was lower among NHOPI (4.7%; P=0.01) and Asians (3.1%; P=0.002) than among whites (12.5%). In the multivariable model, NHOPI (odds ratio, 0.35; 95% confidence interval, 0.12-0.98) and Asians (odds ratio, 0.23; 95% confidence interval, 0.07-0.74) were less likely to be treated with intravenous tissue-type plasminogen activator than whites.

CONCLUSIONS

NHOPI have greater cardiovascular risk factors than whites, but there were no differences in stroke subtypes between the ethnic groups. Furthermore, NHOPI and Asians may be less likely to be treated with intravenous tissue-type plasminogen activator than whites.

Cost-Effectiveness of Echocardiography to Identify Intracardiac Thrombus among Patients with First Stroke or Transient Ischemic Attack

Background and Purpose . Echocardiography to select stroke patients for targeted treatments, such as anticoagulation (AC), to reduce recurrent stroke risk is controversial. The authors' objective was to evaluate the cost-effectiveness of imaging strategies that use transthoracic (TTE) and transesophageal (TEE) echocardiography for identifying intracardiac thrombus in new stroke patients. Methods . Model-based cost-effectiveness analysis of 7 echocardiographic imaging strategies and 2 nontesting strategies with model parameters based on systematic evidence review related to effectiveness of echocardiography in newly diagnosed ischemic stroke patients (white males aged 65 years in base case). Primary outcome was cost per quality-adjusted life year (QALY). Results . All strategies containing TTE were dominated by others and were eliminated from the analysis. Assuming that AC reduces recurrent stroke risk from intracardiac thrombus by 43% over 1 year, TEE generated a cost per QALY of $137,000 (relative to standard treatment) among patients with 5% thrombus prevalence. Cost per QALY dropped to $50,000 in patients with at least 15% intracardiac thrombus prevalence, or, if an 86% relative risk reduction with AC is assumed, in patients with thrombus prevalence of at least 6%. Probabilistic analyses indicate considerable uncertainty around the cost-effectiveness of echocardiography across a wide range of intracardiac thrombus prevalence (pretest probability). Conclusions . Current evidence on cost-effectiveness is insufficient to justify widespread use of echocardiography in stroke patients. Additional research on recurrent stroke risk in patients with intracardiac thrombus and on the efficacy of AC in reducing that risk may contribute to a better understanding of the circumstances under which echocardiography will be cost-effective. Key words: cost-effectiveness; decision analysis; stroke; transesophageal echocardiography; transthoracic echocardiography; diagnostic imaging. (Med Decis Making 2007;27:161—177)

Inflammatory and metabolic markers and short-time outcome in patients with acute ischemic stroke in relation to TOAST subtypes

The aim of this study was to evaluate the association between inflammatory and metabolic markers and short-time outcome with acute ischemic stroke subtypes. A total of 121 patients was classified according to TOAST criteria, such as large artery atherosclerosis (LAAS), lacunar infarct (LAC), cardioembolic infarct (CEI), other determined etiology (ODE), and undetermined etiology (UDE). The functional impairment was evaluated within the first eight hours of stroke and the outcome after three-month follow-up using the modified Rankin Scale. Blood samples were obtained up to 24 h of stroke. Compared with 96 controls, patients with LAAS, CEI, and LAC subtypes showed higher levels of white blood cells, high-sensitivity C-reactive protein (hsCRP), interleukin 6 (IL-6), metalloproteinase 9 (MMP-9), glucose, and iron (p < 0.05); and lower high-density lipoprotein cholesterol (HDL-C) (p < 0.0001); platelets, insulin, insulin resistance, and homocysteine were higher in LAC (p < 0.0001); ferritin was higher in LAAS (p < 0.0001); and total cholesterol (TC) was lower in LAAS and CEI (p < 0.01). When stroke subtypes were compared, insulin was higher in LAAS vs. LAC and in LAC vs. CEI (p < 0.05); and TC was lower in LAAS vs. LAC (p < 0.05). Outcome and rate of mortality after three-month were higher in LAAS vs. LAC (p < 0.001 and p = 0.0391 respectively). The results underscored the important role of the inflammatory response and metabolic changes in the pathogenesis of ischemic stroke subtypes that might be considered on the initial evaluation of stroke patients to identify those that could benefit with individualized therapeutic strategies that taken into account these markers after acute ischemic event.

Access to the carotid artery bifurcation: Cadaveric study with application to nasotracheal intubation as a technique to improve access to a high carotid artery bifurcation

Carotid endarterectomy (CEA) is a common and efficacious surgical procedure for the prevention of ischemic stroke due to atherosclerosis of the internal carotid artery (ICA). A high common carotid artery bifurcation can make CEA technically difficult due to limited carotid artery exposure. A cadaveric study was performed to evaluate the efficacy of nasotracheal intubation for improving access to a high carotid artery bifurcation. Based on this study, nasotracheal intubation does not improve access to a high carotid artery bifurcation as compared with orotracheal intubation.

Meta-Analysis of Genome-Wide Association Studies Identifies Genetic Risk Factors for Stroke in African Americans

BACKGROUND AND PURPOSE

The majority of genome-wide association studies (GWAS) of stroke have focused on European-ancestry populations; however, none has been conducted in African Americans, despite the disproportionately high burden of stroke in this population. The Consortium of Minority Population Genome-Wide Association Studies of Stroke (COMPASS) was established to identify stroke susceptibility loci in minority populations.

METHODS

Using METAL, we conducted meta-analyses of GWAS in 14 746 African Americans (1365 ischemic and 1592 total stroke cases) from COMPASS, and tested genetic variants with P<10(-6) for validation in METASTROKE, a consortium of ischemic stroke genetic studies in European-ancestry populations. We also evaluated stroke loci previously identified in European-ancestry populations.

RESULTS

The 15q21.3 locus linked with lipid levels and hypertension was associated with total stroke (rs4471613; P=3.9×10(-8)) in African Americans. Nominal associations (P<10(-6)) for total or ischemic stroke were observed for 18 variants in or near genes implicated in cell cycle/mRNA presplicing (PTPRG, CDC5L), platelet function (HPS4), blood-brain barrier permeability (CLDN17), immune response (ELTD1, WDFY4, and IL1F10-IL1RN), and histone modification (HDAC9). Two of these loci achieved nominal significance in METASTROKE: 5q35.2 (P=0.03), and 1p31.1 (P=0.018). Four of 7 previously reported ischemic stroke loci (PITX2, HDAC9, CDKN2A/CDKN2B, and ZFHX3) were nominally associated (P<0.05) with stroke in COMPASS.

CONCLUSIONS

We identified a novel genetic variant associated with total stroke in African Americans and found that ischemic stroke loci identified in European-ancestry populations may also be relevant for African Americans. Our findings support investigation of diverse populations to identify and characterize genetic risk factors, and the importance of shared genetic risk across populations.

Genetics of cerebral small vessel disease

Cerebral small vessel disease (SVD) is an important cause of stroke and cognitive impairment among the elderly and is a more frequent cause of stroke in Asia than in the US or Europe. Although traditional risk factors such as hypertension or diabetes mellitus are important in the development of cerebral SVD, the exact pathogenesis is still uncertain. Both, twin and family history studies suggest heritability of sporadic cerebral SVD, while the candidate gene study and the genome-wide association study (GWAS) are mainly used in genetic research. Robust associations between the candidate genes and occurrence of various features of sporadic cerebral SVD, such as lacunar infarction, intracerebral hemorrhage, or white matter hyperintensities, have not yet been elucidated. GWAS, a relatively new technique, overcomes several shortcomings of previous genetic techniques, enabling the detection of several important genetic loci associated with cerebral SVD. In addition to the more common, sporadic cerebral SVD, several single-gene disorders causing cerebral SVD have been identified. The number of reported cases is increasing as the clinical features become clear and diagnostic examinations are more readily available. These include cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy, COL4A1-related cerebral SVD, autosomal dominant retinal vasculopathy with cerebral leukodystrophy, and Fabry disease. These rare single-gene disorders are expected to play a crucial role in our understanding of cerebral SVD pathogenesis by providing animal models for the identification of cellular, molecular, and biochemical changes underlying cerebral small vessel damage.

Ischemic stroke subtype and presence of sleep-disordered breathing: the BASIC sleep apnea study

BACKGROUND

Little is known about the prevalence of sleep-disordered breathing (SDB) across ischemic stroke subtypes. Given the important implications for SDB screening, we tested the association between SDB and ischemic stroke subtype in a population-based study.

METHODS

Within the Brain Attack Surveillance in Corpus Christi Project, ischemic stroke patients were offered SDB screening with the ApneaLink Plus (n = 355). A neurologist assigned Trial of the ORG 10172 in Acute Stroke Treatment subtype (with an additional category for nonlacunar infarctions of unknown etiology) using hospital records. Unadjusted and adjusted (demographics, body mass index, National Institutes of Health Stroke Scale, diabetes, history of stroke/transient ischemic attack) logistic and linear regression models were used to test the association between subtype and SDB or apnea-hypopnea index (AHI).

RESULTS

Median age was 65%, and 55% were men; 59% were Mexican American. Median time from stroke onset to SDB screen was 13 days (interquartile range [IQR] 6, 21). Overall, 215 (61%) had SDB (AHI ≥ 10). Median AHI was 13 (IQR 6, 27). Prevalence of SDB by subtype was cardioembolism, 66%; large-artery atherosclerosis, 57%; small-vessel occlusion, 68%; other determined, 50%; undetermined etiology, 58%; and nonlacunar stroke of unknown etiology, 63%. Ischemic stroke subtype was not associated with SDB in unadjusted (P = .72) or adjusted models (P = .91) models. Ischemic stroke subtype was not associated with AHI in unadjusted (P = .41) or adjusted models (P = .62).

CONCLUSIONS

In this population-based stroke surveillance study, ischemic stroke subtype was not associated with the presence or severity of SDB. Sleep-disordered breathing is likely to be present after ischemic stroke, and the subtype should not influence decisions about SDB screening.

Mechanisms and treatment of ischaemic stroke--insights from genetic associations

The precise pathophysiology of ischaemic stroke is unclear, and a greater understanding of the different mechanisms that underlie large-artery, cardioembolic and lacunar ischaemic stroke subtypes would enable the development of more-effective, subtype-specific therapies. Genome-wide association studies (GWASs) are identifying novel genetic variants that associate with the risk of stroke. These associations provide insight into the pathophysiological mechanisms, and present opportunities for novel therapeutic approaches. In this Review, we summarize the genetic variants that have been linked to ischaemic stroke in GWASs to date and discuss the implications of these associations for both our understanding and treatment of ischaemic stroke. The majority of genetic variants identified are associated with specific subtypes of ischaemic stroke, implying that these subtypes have distinct genetic architectures and pathophysiological mechanisms. The findings from the GWASs highlight the need to consider whether therapies should be subtype-specific. Further GWASs that include large cohorts are likely to provide further insights, and emerging technologies will complement and build on the GWAS findings.

Modelling, evaluating and implementing cost-effective services to reduce the impact of stroke

Background

Stroke is a leading cause of death and disability but there is little information on the longer-term needs of patients and those of different ethnic groups.

Objectives

To estimate risk of stroke, longer-term needs and outcomes, risk of recurrence, trends and predictors of effective care, to model cost-effective configurations of care, to understand stakeholders’ perspectives of services and to develop proposals to underpin policy.

Design

Population-based stroke register, univariate and multivariate analyses, Markov and discrete event simulation, and qualitative methods for stakeholder perspectives of care and outcome.

Setting

South London, UK, with modelling for estimates of cost-effectiveness.

Participants

Inner-city population of 271,817 with first stroke in lifetime between 1995 and 2012.

Outcome measures

Stroke incidence rates and trends, recurrence, survival, activities of daily living, anxiety, depression, quality of life, appropriateness and cost-effectiveness of care, and qualitative narratives of perspectives.

Data sources

South London Stroke Register (SLSR), qualitative data, group discussions.

Results

Stroke incidence has decreased since 1995, particularly in the white population, but with a higher stroke risk in black groups. There are variations in risk factors and types of stroke between ethnic groups and a large number of strokes occurred in people with untreated risk factors with no improvement in detection observed over time. A total of 30% of survivors have a poor range of outcomes up to 10 years after stroke with differences in outcomes by sociodemographic group. Depression affects over half of all stroke patients and the prevalence of cognitive impairment remains 22%. Survival has improved significantly, particularly in the older black groups, and the cumulative risk of recurrence at 10 years is 24.5%. The proportion of patients receiving effective acute stroke care has significantly improved, yet inequalities of provision remain. Using register data, the National Audit Office (NAO) compared the levels of stroke care in the UK in 2010 with previous provision levels and demonstrated that improvements have been cost-effective. The treatment of, and productivity loss arising from, stroke results in total societal costs of £8.9B a year and 5% of UK NHS costs. Stroke unit care followed by early supported discharge is a cost-effective strategy, with the main gain being years of life saved. Half of stroke survivors report unmet long-term needs. Needs change over time, but may not be stroke specific. Analysis of patient journeys suggests that provision of care is also influenced by structural, social and personal characteristics.

Conclusions/recommendations

The SLSR has been a platform for a range of health services research activities of international relevance. The programme has produced data to inform policy and practice with estimates of need for stroke prevention and care services, identification of persistent sociodemographic inequalities in risk and care despite a reduction in stroke risk, quantification of the effectiveness and cost-effectiveness of care and development of models to simulate configurations of care. Stroke is a long-term condition with significant social impact and the data on need and economic modelling have been utilised by the Department of Health, the NAO and Healthcare for London to assess need and model cost-effective options for stroke care. Novel approaches are now required to ensure that such information is used effectively to improve population and patient outcomes.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme and the Department of Health via the National Institute for Health Research Biomedical Research Centre award to Guy’s and St Thomas’ NHS Foundation Trust in partnership with King’s College London.

The relationship between plasma D-dimer levels and outcome of Chinese acute ischemic stroke patients in different stroke subtypes

High-level plasma D-dimer suggests hypercoagulable states. There is a lack of correlation study of plasma D-dimer level and prognosis according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. The goal of this study is to explore the relationship between the plasma D-dimer level and the outcome of acute ischemic stroke patients among different stroke subtypes. We conducted a study of acute ischemic stroke patients admitted to the Department of Neurology in Second Hospital of Lanzhou University within 7 days of symptom onset. They were divided into different groups based on their subtypes according to TOAST criteria. In all the patients the plasma D-dimer levels were detected within 24 h of admission. Clinical neurological assessments were performed in line with National Institutes of Health Stroke Scale (NIHSS) once daily on the day of admission and on the 14th day. The outcome was evaluated by neurological improvement rate. Comparisons were made among the different subtypes based on the level of plasma D-dimer and the outcome. A total of 300 patients with acute ischemic stroke were included, 40 with cardioembolism; 47 with large-artery atherosclerosis; 143 with small-artery occlusion, 5 with other etiology stroke; and 65 with undetermined etiology stroke. The level of plasma D-dimer was negatively related to the outcome (r = -0.41; P = 0.013). Patients with cardioembolism had the highest level of plasma D-dimer and they suffered the most serious neurological deficit and the worst outcome among the five subtypes, the difference was statistically significant (F = 5.34; P = 0.012); while the lacunar stroke patients had the best outcome with the lowest level of D-dimer. High-level plasma D-dimer of acute period strongly indicates an unfavorable clinical outcome.

Racial and ethnic disparities in stroke subtypes: a multiethnic sample of patients with stroke

Stroke subtypes have been reported to differ by race and ethnic subgroups and have not been adequately explained. We aim to evaluate if the prevalence of vascular risk factors accounts for differences observed in stroke subtypes by race/ethnicity. Patients with acute stroke were prospectively enrolled in the Miami Stroke Registry. Patients' demographic, clinical and radiological characteristics were systematically collected. Stroke subtypes were ascertained using TOAST criteria. The sample was divided into Non-Hispanic Whites (NHW), Hispanics, African Americans (AA), and Non-Hispanic Black Caribbean (NHBC). Univariable and multivariable logistic regression analyses were performed to assess differences among groups. Among 473 stroke patients (mean age 64 ± 14 years; 63.7% were men) of which 52.9% were Hispanic, 22.6% were AA, 13.5% NHBC and 11.0% were NHW. Large artery atherosclerosis was more prevalent in NHBC (OR 1.74, 95% CI 1.02-2.97) than in the other groups. Adjusting for covariates rendered the association not significant (OR 1.71, 95% CI 0.93-3.16). Cardioembolism was more frequent in Hispanics (OR 1.94, 95% CI 1.28-2.96) and NHW (OR 2.66, 95% CI 1.42-4.96) as compared to NHBC and AA combined. Adjusting for covariates, the association was no longer significant for Hispanics but was further strengthened for NHW (OR 3.02, 95% CI 1.42-6.42). Our results suggest that the vascular risk factors prevalence among different racial and ethnic groups partially explains disparities found in the prevalence of some stroke subtypes. Addressing health disparities remains an important public health aspect of stroke prevention.

The brain's heart - therapeutic opportunities for patent foramen ovale (PFO) and neurovascular disease

Patent foramen ovale (PFO), a common congenital cardiac abnormality, is a connection between the right and left atria in the heart. As a "back door to the brain", PFO can serve as a conduit for paradoxical embolism, allowing venous thrombi to enter the arterial circulation, avoiding filtration by the lungs, and causing ischemic stroke. PFO-related strokes affect more than 150,000 people per year in the US, and PFO is present in up to 60% of migraine patients with aura, and in one out of four normal individuals. So, in such a highly prevalent condition, what are the best treatment and prevention strategies? Emerging studies show PFO-related neurovascular disease to be a multi-organ condition with varying individual risk factors that may require individualized therapeutic approaches - opening the field for new pharmacologic and therapeutic targets. The anatomy of PFO suggests that, in addition to thrombi, it can also allow harmful circulatory factors to travel directly from the venous to the arterial circulation, a concept important in finding novel therapeutic targets for PFO-related neurovascular injury. Here, we: 1) review emerging data on PFO-related injuries and clinical trials; 2) discuss potential mechanisms of PFO-related neurovascular disease in the context of multi-organ interaction and heart-brain signaling; and 3) discuss novel therapeutic targets and research frontiers. Clinical studies and molecular mapping of the circulatory landscape of this multi-organ disease will both be necessary in order to better individualize clinical treatment for a condition affecting more than a quarter of the world's population.

Pharmaco-proteomics opportunities for individualizing neurovascular treatment

Neurovascular disease often involves multi-organ system injury. For example, patent foramen ovale (PFO) related ischemic strokes involve not just the brain, but also the heart, the lung, and the peripheral vascular circulation. For higher-risk but high-reward systemic therapy (e.g., thrombolytics, therapeutic hypothermia (TH), PFO closure) to be implemented safely, very careful patient selection and close monitoring of disease progression and therapeutic efficacy are imperative. For example, more than a decade after the approval of therapeutic hypothermic and intravenous thrombolysis treatments, they both remain extremely under-utilized, in part due to lack of clinical tools for patient selection or to follow therapeutic efficacy. Therefore, in understanding the complexity of the global effects of clinical neurovascular diseases and their therapies, a systemic approach may offer a unique perspective and provide tools with clinical utility. Clinical proteomic approaches may be promising to monitor systemic changes in complex multi-organ diseases - especially where the disease process can be 'sampled' in clinically accessible fluids such as blood, urine, and CSF. Here, we describe a 'pharmaco-proteomic' approach to three major challenges in translational neurovascular research directly at bedside - in order to better stratify risk, widen therapeutic windows, and explore novel targets to be validated at the bench - (i) thrombolytic treatment for ischemic stroke, (ii) therapeutic hypothermia for post-cardiac arrest syndrome, and (iii) treatment for PFO related paradoxical embolic stroke. In the future, this clinical proteomics approach may help to improve patient selection, ensure more precise clinical phenotyping for clinical trials, and individualize patient treatment.

Serum non-high-density lipoprotein cholesterol levels and the incidence of ischemic stroke in a Japanese population: the Jichi Medical School cohort study

The predictive value of serum non-high-density lipoprotein cholesterol (non-HDL-C) levels for the incidence of ischemic stroke and its subtypes has not yet been established. The present cohort study investigated their relationships in a Japanese population. The first incidence of ischemic stroke and its subtypes was documented as the primary outcome. A total of 249 ischemic stroke patients (men/women = 145/104) were identified during a follow-up period of 10.7 years among 10 760 community-dwelling subjects (men/women = 4212/6548). Cox proportional hazard model analyses revealed that when compared with the lowest tertile of non-HDL-C, multivariate-adjusted hazard ratios for the highest tertile were 0.55 (95% confidence interval = 0.32-0.95, P = .03) on ischemic stroke and 0.29 (95% confidence interval = 0.08-1.05, P = .06) on cardioembolic infarction in women. Men did not show such significant relationships. Low serum non-HDL-C levels may be a predictive marker associated with an increase in the incidence of ischemic stroke and possibly of cardioembolic infarction in Japanese women.

Premature menopause or early menopause and risk of ischemic stroke

OBJECTIVE

The general consensus has been that estrogen is invariably a risk factor for ischemic stroke (IS). We reviewed new observational studies that challenge this simple conclusion.

METHODS

This was a review of observational studies of the association of premature or early menopause with stroke or IS published in English from 2006 through 2010.

RESULTS

Three cohort studies showed an increased risk of all types of stroke in women who underwent bilateral oophorectomy compared with women who conserved their ovaries before age 50 years. The increased risk of stroke was reduced by hormone therapy in one of the studies, suggesting that estrogen deprivation is involved in the association. Four additional observational studies showed an association of all types of stroke or IS with the early onset of menopause or with a shorter life span of ovarian activity. In three of the seven studies, the association was restricted to IS. Age at menopause was more important than type of menopause (natural vs induced).

CONCLUSIONS

The findings from seven recent observational studies challenge the consensus that estrogen is invariably a risk factor for IS and can be reconciled by a unifying timing hypothesis. We hypothesize that estrogen is protective for IS before age 50 years and may become a risk factor for IS after age 50 years or, possibly, after age 60 years. These findings are relevant to women who experienced premature or early menopause or to women considering prophylactic bilateral oophorectomy before the onset of natural menopause.

Racial differences by ischemic stroke subtype: a comprehensive diagnostic approach

Background. Previous studies have suggested that black populations have more small-vessel and fewer cardioembolic strokes. We sought to analyze racial differences in ischemic stroke subtype employing a comprehensive diagnostic workup with magnetic resonance-imaging-(MRI-) based evaluation including diffusion-weighted imaging (DWI). Methods. 350 acute ischemic stroke patients admitted to an urban hospital with standardized comprehensive diagnostic evaluations were retrospectively analyzed. Ischemic stroke subtype was determined by three Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification systems. Results. We found similar proportions of cardioembolic and lacunar strokes in the black and white cohort. The only subtype category with a significant difference by race was “stroke of other etiology,” more common in whites. Black stroke patients were more likely to have an incomplete evaluation, but this did not reach significance. Conclusions. We found similar proportions by race of cardioembolic and lacunar strokes when employing a full diagnostic evaluation including DWI MRI. The relatively high rate of cardioembolism may have been underappreciated in black stroke patients when employing a CT approach to stroke subtype diagnosis. Further research is required to better understand the racial differences in frequency of “stroke of other etiology” and explore disparities in the extent of diagnostic evaluations.

The risk factors of CVA in Jordan

This study aimed to identify the main risk factors of cerebrovascular accident (CVA) in Jordan. Identification of risk factors may help to reduce the incidence of CVA. A form was prepared for data collection which consisted of two parts to gather biodata and the incidence of risk factors. A sample of 200 patients with CVA (60% men) were randomly selected from various areas of Jordan. An age, region distribution, and gender-matched sample were selected to serve as control. Hypertension in the experimental group (66%) was significantly higher than the control group (32%) p  <  0.001. Half of the subjects with stroke had diabetes compared to 22% of the control group (p  <  0.001). Cardiovascular diseases were found in 29% of subjects with CVA compared to 14% in the control group (p  <  0.001). About 27% of the CVA group had hyperlipidemia in comparison to 13% in the controls (p <  0.002). Smokers represented 54% of the experimental group compared to 30% of the control group (p <  0.05). An important finding in the present study was that about half of the selected subjects with strokes were under the age of 60 years. In conclusion, hypertension, diabetes, cardiovascular diseases, hyperlipidemia, and smoking are risk factors for CVA in Jordan.

Treatment of risk factors to prevent stroke

Much of the decline in stroke incidence and mortality for the past several decades in Western countries has been attributed to better treatment of risk factors. Many epidemiological studies and clinical trials confirmed the importance of managing hypertension. Comparative trials of anti-hypertensive drugs or drug classes have not yielded clear results, but blood pressure variability may play an important role beyond the absolute value of blood pressure. Diabetes therapy remains a conundrum. Although diabetes is clearly a risk factor for ischemic stroke, treatment trials targeting different glycemic goals have not indicated that glucose lowering results in stroke prevention. Trials focused on insulin resistance are ongoing and they may be able to help establish the management of diabetes/impaired glucose tolerance. Evidence for treatment of dyslipidemia has contrasted science to diabetes mellitus. Dyslipidemia has not been strongly or consistently linked to ischemic stroke but the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial showed the impact of statin treatment in stroke prevention. The results of clinical trials investigating dabigatran and rivaroxaban clearly indicate alternative strategies to vitamin K antagonists in stroke prevention for persons with atrial fibrillation. Evidence for stroke prevention by life style modification, treating metabolic syndrome, sleep disordered breathing, lipoprotein (a), hyperhomocysteinemia, and coagulation disorders are also discussed.

Discharge medications among ischemic stroke survivors

BACKGROUND

The aim of this study was to analyze the types and cost of medications prescribed at discharge for ischemic stroke survivors.

METHODS

This is a descriptive study of medications prescribed for ischemic stroke survivors admitted to Al-watani hospital during a 6-month period.

RESULTS

A total of 95 consecutive stroke patients were included in the study period; 78 (82.1%) survivors were having ischemic stroke subtype and were designated the study group. The average age of the survivors was 66.9 +/- 12.7 years. Survivors had prevalent risk factors such as diabetes mellitus (70%), hypertension (68%), and ischemic heart disease (34.6%). On average, survivors experienced a minimum of 0.73 complications (range 0-3) with the most common being infections (n = 35, 44.8%). Forty-two per cent of the ischemic stroke survivors were taking antiplatelet drugs prior to the current attack. At discharge, ischemic stroke survivors were prescribed an average of 4.9 medications from 4.3 different drug classes. All ischemic stroke survivors were prescribed antiplatelet therapy at discharge. Aspirin monotherapy was prescribed for 61 survivors while the combination of aspirin/clopidogrel antiplatelet therapy was prescribed for 17 survivors. The average monthly cost for prophylactic therapy and for medications used to treat post-stroke complication was approximately 52 USD per survivor.

CONCLUSION

Most of the patients in the study group were having the traditional risk factors for ischemic stroke and were suffering form typical post-stroke complications. Lack of medical insurance will impose a heavy financial burden on stroke survivors in Palestine.

Age-distinct predictors of symptomatic cervicocephalic atherosclerosis

BACKGROUND

Little is known about whether vascular risk factors predispose to atherosclerotic stroke depending on age. We evaluated predictors of large vessel atherosclerotic stroke (LVAS) stratified by age in two geographically and racially distinct study populations.

METHODS

Data collected over a 4-year period in prospectively maintained registries on 3,053 subjects with ischemic cerebrovascular events were analyzed: 1,982 patients from a hospital in South Korea and 1,071 patients admitted to a hospital in Los Angeles, Calif., USA. Independent vascular risk factor associations with LVAS mechanism were evaluated in three groups stratified by age (years) at symptom onset: young (<or=50 years), older (51-75 years), and oldest (>75 years).

RESULTS

Altogether at both study sites, 972 (31.8%) patients had LVAS mechanism, of whom 391 (40.2%) were female. Risk factor profiles were not significantly different between LVAS versus other stroke mechanisms. Among young patients, after adjusting for covariates, current smoking was the only predictor of atherosclerotic stroke at both Korean (OR 2.04; 95% CI: 1.13-3.69) and Californian sites (OR 4.78, 95% CI 1.54-14.89), while the metabolic syndrome was the only predictor of atherosclerotic stroke among the older patients (OR 1.58, 95% CI 1.17-2.12 for Korean; OR 1.75, 95% CI 1.07-2.84 for Californian), but not in the young or oldest groups.

CONCLUSIONS

Across race and region, the estimated impact of vascular risk factors for LVAS varies by age, and this is most prominently seen among persons of less than 76 years of age. Some risk factors have an early effect (smoking) and others an effect that plays out over time.

Prevalence of cardiovascular risk factors among elderly Brazilians over eighty with ischemic stroke

INTRODUCTION: An ischemic stroke is usually a catastrophic event, mostly in the elderly. Cardiovascular involvement is the leading cause of ischemic stroke in this age population and hence the knowledge about its risk factors is important for the definition of specific policies of prevention. PURPOSE: To evaluate the prevalence of cardiovascular risk factors in patients with age equal to or above 80 in a hospital population with ischemic stroke. METHOD: Retrospective study of consecutive patients diagnosed with ischemic stroke admitted to a tertiary health facility. RESULTS: From September 2004 to March 2006, 215 patients were studied. There was a female preponderance (p<0.01). Among patients over eighty, 72% had hypertension and atrial fibrillation was more common among the oldest old (p<0.01). CONCLUSION: Hypertension and atrial fibrillation should be treated aggressively in the elderly. Anticoagulants should be considered more often in these patients.

Interobserver agreement in the trial of org 10172 in acute stroke treatment classification of stroke based on retrospective medical record review

BACKGROUND

The reliability of the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification system of stroke in siblings of stroke-affected probands has not been tested. Similarly, the reliability of using clinical medical records to classify ischemic stroke has not been assessed. The purpose of this study was to establish the interrater reliability of sibling stroke subtyping by applying the TOAST criteria to retrospectively obtained medical records.

METHODS

Thirty medical records were randomly sampled from among the records of all siblings previously classified as stroke affected by the Siblings with Ischemic Stroke Study (SWISS) Stroke Verification Committee. Blinded medical records for these individuals were sent to 6 physician reviewers who independently classified TOAST stroke subtype on the basis of record review.

RESULTS

Using the kappa statistic to assess interrater reliability, the overall reliability (SE) for assigning a TOAST subtype of stroke was 0.54 (0.03). Pair-wise comparisons between the original SWISS Stroke Verification Committee diagnoses and the diagnoses made by other reviewers exhibited moderate reliability (kappa range 0.41-0.56). The kappa statistics for common stroke subtypes were large vessel, 0.80 (0.06); cardioembolic, 0.80 (0.06); small vessel, 0.53 (0.06); and unknown cause, 0.40 (0.06).

CONCLUSION

We conclude that TOAST subtyping had moderate interrater reliability. Large-artery and cardioembolic subtype diagnoses seemed most reliable.

Racial disparities in the filling of warfarin prescriptions for nonvalvular atrial fibrillation

BACKGROUND

Warfarin has been shown to decrease the rate of thromboembolic events in patients with nonvalvular atrial fibrillation, but it is frequently underprescribed. Our goal was to establish whether there have been racial disparities in the filling of warfarin prescriptions for patients with newly incident nonvalvular atrial fibrillation.

METHODS

We conducted a retrospective analysis of Ohio Medicaid claims between January 1, 1997 and May 31, 2002, for recipients with newly incident nonvalvular atrial fibrillation. Race was identified from the demographic information in the database, and the analysis was limited to white and African-American patients. The main outcome measure was the filling of a prescription for warfarin at any time between 7 days prior to the initial diagnosis of atrial fibrillation and 30 days after the initial diagnosis. To evaluate the independent role of race in the filling of warfarin prescriptions, we created a multivariable logistic regression model incorporating predictors significant at P < 0.10 in the univariate model.

RESULTS

A total of 6283 patients were identified as having newly incident nonvalvular atrial fibrillation, 18.5% of whom were African-American. In general, African-American patients had a higher rate of comorbid illness. Warfarin prescriptions were filled for 9.4% of white patients and 7.6% of African-American patients. When controlling for significant confounders in the multivariable logistic regression model, African-American patients had an adjusted odds ratio for receiving warfarin of 0.76 (95% CI, 0.60-0.98) when compared with white patients.

CONCLUSION

African-American patients in the Ohio Medicaid population between 1998 and 2002 were significantly less likely than white patients to fill a warfarin prescription for newly incident nonvalvular atrial fibrillation.

Ethnicity and cardiovascular disease prevention in the United Kingdom: a practical approach to management

The United Kingdom is a diverse society with 7.9% of the population from black and minority ethnic groups (BMEGs). The causes of the excess cardiovascular disease (CVD) and stroke morbidity and mortality in BMEGs are incompletely understood though socio-economic factors are important. However, the role of classical cardiovascular (CV) risk factors is clearly important despite the patterns of these risk factors varying significantly by ethnic group. Despite the major burden of CVD and stroke among BMEGs in the UK, the majority of the evidence on the management of such conditions has been based on predominantly white European populations. Moreover, the CV epidemiology of African Americans does not represent well the morbidity and mortality experience seen in black Africans and black Caribbeans, both in Britain and in their native African countries. In particular, atherosclerotic disease and coronary heart disease are still relatively rare in the latter groups. This is unlike the South Asian diaspora, who have prevalence rates of CVD in epidemic proportions both in the diaspora and on the subcontinent. As the BMEGs have been under-represented in research, a multitude of guidelines exists for the 'general population.' However, specific reference and recommendation on primary and secondary prevention guidelines in relation to ethnic groups is extremely limited. This document provides an overview of ethnicity and CVD in the United Kingdom, with management recommendations based on a roundtable discussion of a multidisciplinary ethnicity and CVD consensus group, all of whom have an academic interest and clinical practice in a multiethnic community.

Stroke: epidemiology, classification, risk factors, complications, diagnosis, prevention, and medical and dental management

Cerebrovascular accident, or stroke, refers to an acute onset of neurologic deficits lasting more than 24 hours or culminating in death caused by a sudden impairment of cerebral circulation. Stroke is the third leading cause of death and a major cause of long-term disability in the United States. This article provides the dental community with an up-to-date understanding of the epidemiology, classification, risk factors, complications, diagnosis, prevention, and medical and dental management issues pertaining to stroke.

Population-based study of the relationship between atherosclerotic aortic debris and cerebrovascular ischemic events

OBJECTIVE

To assess the validity of the suggestion that protruding atheromatous material in the thoracic aorta is an important cause of cerebrovascular ischemic events (CIEs) (ie, transient ischemic attack or ischemic stroke).

METHODS

This case-control study of Olmsted County, Minnesota, residents who underwent transesophageal echocardiography (TEE) from 1993 to 1997 included controls without CIE randomly selected from the population, controls without CIE referred for TEE because of cardiac disease, cases with incident CIE of obvious cause (noncryptogenic), and cases with incident CIE of uncertain cause (cryptogenic).

RESULTS

Of the 1135 subjects, 520 were randomly selected controls without CIE, 329 were controls without CIE referred for TEE, 159 were noncryptogenic CIE cases, and 127 were cryptogenic CIE cases. Complex atherosclerotic aortic debris in ascending and transverse segments of the arch was detected in 8 randomly selected controls (1.5%), 13 referred controls (4.0%), and 15 noncryptogenic (9.4%) and 4 cryptogenic (3.1%) CIE cases. After adjusting for age, sex, hypertension, smoking, atrial fibrillation, valvular heart disease, congestive heart failure, and atherosclerosis other than in the thoracic aorta, complex atherosclerotic aortic debris was not significantly associated with group status. With randomly selected controls as the referent group, odds ratios (95% confidence intervals) were 1.72 (0.61-4.87) for referred controls, 3.16 (1.18-8.51) for noncryptogenic CIE cases, and 1.39 (0.39-4.88) for cryptogenic CIE cases.

CONCLUSIONS

Complex atherosclerotic aortic debris is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack but is a marker for generalized atherosclerosis and well-established atherosclerotic and cardioembolic mechanisms of cerebral ischemia. Embolization from the aorta is not a common mechanism of ischemic stroke or transient ischemic attack.

Population-based study of the relationship between patent foramen ovale and cerebrovascular ischemic events

OBJECTIVE

To determine whether patent foramen ovale (PFO) is a risk factor for a cryptogenic cerebrovascular ischemic event (CIE).

METHODS

This case-control study of 1072 residents of Olmsted County, Minnesota, who underwent contrast transesophageal echocardiography between 1993 and 1997 included 519 controls without CIE randomly selected from the population, 262 controls without CIE referred for transesophageal echocardiography because of cardiac disease, 158 cases with incident CIE of obvious cause (noncryptogenic), and 133 cases with incident CIE of uncertain cause (cryptogenic).

RESULTS

Large PFOs were detected in 108 randomly selected controls (20.8%), 22 referred controls (8.4%), 17 noncryptogenic CIE cases (10.8%), and 22 cryptogenic CIE cases (16.5%). After adjustment for age, sex, hypertension, smoking, atrial fibrillation, ischemic heart disease, and number of contrast injections, the presence of a large PFO was not significantly associated with group status (P=.07). Using the odds of the presence of large PFO in the randomly selected controls as the reference, the odds ratio (95% confidence interval) of the presence of large PFO was 0.47 (0.26-0.87) for referred controls, 0.69 (0.37-1.29) for noncryptogenic CIE cases, and 1.10 (0.63-1.90) for cryptogenic CIE cases.

CONCLUSIONS

Patent foramen ovale is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack in the general population. The PFO's importance in the genesis of cryptogenic CIE may have been overestimated in previous studies because of selective referral of cases and underascertainment of PFO among comparison groups of patients referred for echocardiography for clinical indications other than cryptogenic CIE.

A possible explanation for the racial difference in distribution of large-arterial cerebrovascular disease: ancestral European settlers evolved genetic resistance to atherosclerosis, but confined to the intracranial arteries

The pattern of cerebral atherosclerosis is not the same among different races. White patients rarely have intracranial large arterial steno-occlusive disease even if their systemic arteries are extensively involved, while non-white patients frequently have their intracranial arteries affected. We postulate that during human population diversification, those who settled in Europe had acquired a stroke-suppressor genotype that increases their resistance against atherogenesis, but with protection confined to the intracranial large arteries. The contemporary affluent lifestyle accelerates the development of atherosclerosis. In the whites, it involves the whole arterial bed except the intracranial vessels. People living in non-Western countries used to have a healthier way of living. They did not develop significant atherosclerotic diseases until recently when a westernised lifestyle was adopted. Unlike the whites, their intracranial arteries will not be spared. Atherosclerosis has become a major cause of premature mortality in the modern world, and an anti-atherogenic mechanism would confer a selection advantage. With further adaptive intensification, this protection may extend to the rest of the arterial bed. As a result, future Homo sapiens will be able to tolerate an affluent lifestyle without much adverse sequel such as premature vascular death. Alternatively, if the mediator of this anti-atherogenic mechanism can be identified and applied therapeutically, we will have an ultimate mean to prevent atherosclerosis.

Ethnic disparities in incidence of stroke subtypes: Auckland Regional Community Stroke Study, 2002–2003

BACKGROUND

Limited population-based data exist on differences in the incidence of major pathological stroke types and ischaemic stroke subtypes across ethnic groups. We aimed to provide such data within the large multi-ethnic population of Auckland, New Zealand.

METHODS

All first-ever cases of stroke (n=1423) in a population-based register in 940 000 residents (aged 15 years) in Auckland, New Zealand, for a 12-month period in 2002-2003, were classified into ischaemic stroke, primary intracerebral haemorrhage (PICH), subarachnoid haemorrhage, and undetermined stroke, according to standard definitions and results of neuroimaging/necropsy (in over 90% of cases). Ischaemic stroke was further classified into five subtypes. Ethnicity was self-identified and grouped as New Zealand (NZ)/European, Maori/Pacific, and Asian/other. Incidence rates were standardised to the WHO world population by the direct method, and differences in rates between ethnic groups expressed as rate ratios (RRs), with NZ/European as the reference group.

FINDINGS

In NZ/European people, ischaemic stroke comprised 73%, PICH 11%, and subarachnoid haemorrhage 6%, but PICH was higher in Maori/Pacific people (17%) and in Asian/other people (22%). Compared with NZ/European people, age-adjusted RRs for PICH were 2.7 (95% CI 1.8-4.0) and 2.3 (95% CI 1.4-3.7) among Maori/Pacific and Asian/other people, respectively. The corresponding RR for ischaemic stroke was greater for Maori/Pacific people (1.7 [95% CI 1.4-2.0]), particularly embolic stroke, and for Asian/other people (1.3 [95% CI 1.0-1.7]). The onset of stroke in Maori/Pacific and Asian/other people began at significantly younger ages (62 years and 64 years, respectively) than in NZ/Europeans (75 years; p<0.0001). There were ethnic differences in the risk factor profiles (such as age, sex, hypertension, cardiac disease, diabetes, hypercholesterolaemia, smoking status, overweight) for the stroke types and subtypes.

INTERPRETATION

Compared to NZ/Europeans, Maori/Pacific and Asian/other people are at higher risk of ischaemic stroke and PICH, whereas similar rates of subarachnoid haemorrhage were evident across ethnic groups. The ethnic disparities in the rates of stroke types could be due to substantial differences found in risk factor profiles between ethnic groups. This information should be considered when planning prevention and stroke-care services in multi-ethnic communities.

Neuroprotective effects of a postischemic treatment with a bradykinin B2 receptor antagonist in a rat model of temporary focal cerebral ischemia

Bradykinin, an endogenous nonapeptide produced by activation of the kallikrein-kinin system, promotes neuronal tissue damage as well as disturbances in blood-brain barrier function through activation of B2 receptors. In a rat model of focal cerebral ischemia, blockade of B2 receptors before initiation of ischemia with the B2 receptor antagonist, LF 16-0687 Ms, afforded substantial neuroprotection. In order to assess the potential clinical value of this approach, we evaluated the effect of LF 16-0687 Ms given at reperfusion following focal cerebral ischemia on local cerebral blood flow (LCBF), neurological outcome, and infarct size. Sprague-Dawley rats were subjected to MCA occlusion for 90 min by an intraluminal filament. Animals were assigned to one of four treatment arms (n = 7 each): (1) vehicle, (2) LF 16-0687 Ms (1.0 mg/kg/day), (3) LF 16-0687 Ms (3.0 mg/kg/day), or (4) LF 16-0687 Ms (10.0 mg/kg/day) given at reperfusion and repetitively over 2 days. Neurological recovery was examined daily, and infarct volume was assessed histologically on day 7 after ischemia. Physiological parameters and local CBF were not influenced by the treatment. Significant improvement of neurological outcome was observed on postischemic day 3 in animals receiving 1.0 and 3.0 mg/kg/day of LF 16-0687 Ms (P < 0.05). Inhibition of B2 receptors significantly reduced infarct volume in all treated animals predominantly in the cortex. B2 receptor blockade with LF 16-0687 Ms showed neuroprotective effectiveness even when therapy was initiated upon reperfusion, i.e. 90 min after induction of ischemia. Therefore, blockade of B2 receptors seems to be a promising therapeutic approach after focal cerebral ischemia, which deserves further experimental and clinical evaluation.

Difficult retrieval of the EPI filterwire with a 5 French FR4 coronary catheter following carotid stenting

Carotid angioplasty and stenting with an embolic protection device is emerging as a reasonable alternative to carotid endarterectomy in high-risk patients. The deployment and retrieval of these devices, however, can be problematic. We describe a case where a 5 Fr FR4 coronary catheter was used to retrieve an EPI Filterwire device following carotid stenting.

Lipids and stroke: the opportunity of lipid-lowering treatment

Dyslipemia is a clear risk factor (RF) for ischemic heart disease and peripheral artery disease, but its relation with ischemic stroke (IS) is not so clear. HMG-CoA reductase inhibitor drugs or statins (simvastatin, atorvastatin, pravastatin) reduce the relative risk of IS by between 18 and 51% in patients with IHD, in patients with high vascular disease risk and in hypertensive patients with other RFs, acute coronary syndrome, and type 2 diabetes mellitus. According to the guidelines for use, statins are indicated in the majority of patients with IS since the risk is equivalent to that of IHD or high vascular disease risk. In view of the existing clinical evidence of benefit, it would not seem unreasonable to proceed with treatment of patients using statins while awaiting specific studies justifying their use. The non-lipid-lowering mechanisms of the statins and results of studies, such as the Heart Protection Study, provide evidence for widening the indications of statins beyond the prevention of dyslipemia, as a new therapeutic approach in the prevention of IS in patients with plasma levels of total cholesterol or low density lipoproteins currently considered within the normal distribution. The neuroprotective role, which these drugs may play in the acute phase of cerebral ischemia, remains to be clarified, but very recent evidence suggests that such patients may also benefit.