Intracerebral hemorrhage in blacks. Risk factors, subtypes, and outcome

Prevalence, Characteristics, and Outcomes of Undetermined Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

There are scarce data regarding the prevalence, characteristics and outcomes of intracerebral hemorrhage (ICH) of undetermined (unknown or cryptogenic) etiology. We sought to determine the prevalence, radiological characteristics, and clinical outcomes of undetermined ICH.

METHODS

Systematic review and meta-analysis of studies involving patients with spontaneous ICH was conducted to primarily assess the prevalence and clinical-radiological characteristics of undetermined ICH. Additionally, we assessed the rates for ICH secondary to hypertensive arteriopathy and cerebral amyloid angiopathy. Subgroup analyses were performed based on the use of (1) etiology-oriented ICH classification, (2) detailed neuroimaging, and (3) Boston criteria among patients with cerebral amyloid angiopathy related ICH. We pooled the prevalence rates using random-effects models, and assessed the heterogeneity using Cochran Q and I² statistics.

RESULTS

We identified 24 studies comprising 15 828 spontaneous ICH patients (mean age, 64.8 years; men, 60.8%). The pooled prevalences of hypertensive arteriopathy ICH, undetermined ICH, and cerebral amyloid angiopathy ICH were 50% (95% CI, 43%-58%), 18% (95% CI, 13%-23%), and 12% (95% CI, 7%-17% [P<0.001 between subgroups]). The volume of ICH was the largest in cerebral amyloid angiopathy ICH (24.7 [95% CI, 19.7-29.8] mL), followed by hypertensive arteriopathy ICH (16.2 [95% CI, 10.9-21.5] mL) and undetermined ICH (15.4 [95% CI, 6.2-24.5] mL). Among patients with undetermined ICH, the rates of short-term mortality (within 3 months) and concomitant intraventricular hemorrhage were 33% (95% CI, 25%-42%) and 38% (95% CI, 28%-48%), respectively. Subgroup analysis demonstrated a higher rate of undetermined ICH among studies that did not use an etiology-oriented classification (22% [95% CI, 15%-29%]). No difference was observed between studies based on the completion of detailed neuroimaging to assess the rates of undetermined ICH (P=0.62).

CONCLUSIONS

The etiology of spontaneous ICH remains unknown or cryptogenic among 1 in 7 patients in studies using etiology-oriented classification and among 1 in 4 patients in studies that avoid using etiology-oriented classification. The short-term mortality in undetermined ICH is high despite the relatively small ICH volume.

Tobacco Use: A Major Risk Factor of Intracerebral Hemorrhage

Spontaneous intracerebral hemorrhage (sICH) is one of the deadliest subtypes of stroke, and no treatment is currently available. One of the major risk factors is tobacco use. In this article, we review literature on how tobacco use affects the risk of sICH and also summarize the known effects of tobacco use on outcomes following sICH. Several studies demonstrate that the risk of sICH is higher in current cigarette smokers compared to non-smokers. The literature also establishes that cigarette smoking not only increases the risk of sICH but also increases hematoma growth, results in worse outcomes, and increases the risk of death from sICH. This review also discusses potential mechanisms activated by tobacco use which result in an increase in risk and severity of sICH. Exploring the underlying mechanisms may help alleviate the risk of sICH in tobacco users as well as may help better manage tobacco user sICH patients.

Hemorrhagic stroke

Hemorrhagic stroke comprises about 20% of all strokes, with intracerebral hemorrhage (ICH) being the most common type. Frequency of ICH is increased where hypertension is untreated. ICH in particularly has a disproportionately high risk of early mortality and long-term disability. Until recently, there has been a paucity of randomized controlled trials (RCTs) to provide evidence for the efficacy of various commonly considered interventions in ICH, including acute blood pressure management, coagulopathy reversal, and surgical hematoma evacuation. Evidence-based guidelines do exist for ICH and these form the basis for a framework of care. Current approaches emphasize control of extremely high blood pressure in the acute phase, rapid reversal of vitamin K antagonists, and surgical evacuation of cerebellar hemorrhage. Lingering questions, many of which are the topic of ongoing clinical research, include optimizing individual blood pressure targets, reversal strategies for newer anticoagulant medications, and the role of minimally invasive surgery. Risk stratification models exist, which derive from findings on clinical exam and neuroimaging, but care should be taken to avoid a self-fulfilling prophecy of poor outcome from limiting treatment due to a presumed poor prognosis. Cerebral venous thrombosis is an additional subtype of hemorrhagic stroke that has a unique set of causes, natural history, and treatment and is discussed as well.

Early Prediction of Prognosis in Elderly Acute Stroke Patients

Acute stroke has a high morbidity and mortality in elderly population. Baseline confounding illnesses, initial clinical examination, and basic laboratory tests may impact prognostics. In this study, we aimed to establish a model for predicting in-hospital mortality based on clinical data available within 12 hours of hospital admission in elderly (≥ 65 age) patients who experienced stroke.

DESIGN

Retrospective observational cohort study.

SETTING

Academic comprehensive stroke center.

PATIENTS

Elderly acute stroke patients-2005-2009 (n = 462), 2010-2012 (n = 122), and 2016-2017 (n = 123).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

After institutional review board approval, we retrospectively queried elderly stroke patients' data from 2005 to 2009 (training dataset) to build a model to predict mortality. We designed a multivariable logistic regression model as a function of baseline severity of illness and laboratory tests, developed a nomogram, and applied it to patients from 2010 to 2012. Due to updated guidelines in 2013, we revalidated our model (2016-2017). The final model included stroke type (intracerebral hemorrhage vs ischemic stroke: odds ratio [95% CI] of 0.92 [0.50-1.68] and subarachnoid hemorrhage vs ischemic stroke: 1.0 [0.40-2.49]), year (1.01 [0.66-1.53]), age (1.78 [1.20-2.65] per 10 yr), smoking (8.0 [2.4-26.7]), mean arterial pressure less than 60 mm Hg (3.08 [1.67-5.67]), Glasgow Coma Scale (0.73 [0.66-0.80] per 1 point increment), WBC less than 11 K (0.31 [0.16-0.60]), creatinine (1.76 [1.17-2.64] for 2 vs 1), congestive heart failure (2.49 [1.06-5.82]), and warfarin (2.29 [1.17-4.47]). In summary, age, smoking, congestive heart failure, warfarin use, Glasgow Coma Scale, mean arterial pressure less than 60 mm Hg, admission WBC, and creatinine levels were independently associated with mortality in our training cohort. The model had internal area under the curve of 0.83 (0.79-0.89) after adjustment for over-fitting, indicating excellent discrimination. When applied to the test data from 2010 to 2012, the nomogram accurately predicted mortality with area under the curve of 0.79 (0.71-0.87) and scaled Brier's score of 0.17. Revalidation of the same model in the recent dataset from 2016 to 2017 confirmed accurate prediction with area under the curve of 0.83 (0.75-0.91) and scaled Brier's score of 0.27.

CONCLUSIONS

Baseline medical problems, clinical severity, and basic laboratory tests available within the first 12 hours of admission provided strong independent predictors of in-hospital mortality in elderly acute stroke patients. Our nomogram may guide interventions to improve acute care of stroke.

Relationship between race and outcome in Asian, Black, and Caucasian patients with spontaneous intracerebral hemorrhage: Data from the Virtual International Stroke Trials Archive and Efficacy of Nitric Oxide in Stroke trial

Background and purpose Although poor prognosis after intracerebral hemorrhage relates to risk factors and hematoma characteristics, there is limited evidence for the effect of race-ethnicity. Methods Data from 1011 patients with intracerebral hemorrhage enrolled into hyperacute trials and randomized to control were obtained from the Virtual International Stroke Trials Archive and Efficacy of Nitric Oxide in Stroke Trial. Clinical characteristics and functional outcome were compared among three racial groups - Asians, Blacks, and Caucasians. Results The majority of patients were Caucasian (78.1%) followed by Asians (14.5%) and Blacks (5.5%). At baseline, Caucasians were older and had larger hematoma volumes; Blacks had lower Glasgow Coma Scale and higher systolic blood pressure (all p < 0.05). Although the primary outcome of modified Rankin Scale did not differ at 90 days (p = 0.14), there were significant differences in mortality (p < 0.0001) and quality of life (EQ-5D p < 0.0001; EQ-VAS p 0.015). In test of multiple comparisons, Caucasians were more likely to die (p = 0.0003) and had worse quality of life (EQ-5D p = 0.003; EQ-VAS p < 0.0001) as compared to Asians. Conclusion Race-ethnicity appears to explain some of the variation in clinical characteristics and outcomes after acute intracerebral hemorrhage. Factors that explain this variation need to be identified.

The genetics of sporadic ruptured and unruptured intracranial aneurysms: a genetic meta-analysis of 8 genes and 13 polymorphisms in approximately 20,000 individuals

Object

Intracranial aneurysms (IAs) are thought to have a multifactorial origin. The authors undertook a comprehensive meta-analysis on all genes investigated using a case-control model in ruptured (subarachnoid hemorrhage) and unruptured aneurysms.

Methods

Electronic databases were searched until and including July 2008 for any candidate gene studied in IA or subarachnoid hemorrhage using a case-control model. The ORs and 95% CIs were determined for each gene-disease association using fixed and random effect models.

Results

Thirty studies of 8 genes and 13 polymorphisms were analyzed among 19,961 individuals (6622 cases and 13,339 controls). Two genes and 3 polymorphisms were associated with IA. The eNOS gene T786C polymorphism (OR 1.24, 95% CI 1.0–1.54; p = 0.05) and IL-6 gene G572C polymorphism (OR 7.08, 95% CI 2.85–17.57; p < 0.0001) both showed a significant association with ruptured/unruptured IA. The IL-6/G174C polymorphism exerted a significant protective effect against IA (OR 0.49, 95% CI 0.25–0.95; p = 0.04). The other candidate genes investigated (ACE, endoglin, APOE, elastin, MMP-3, and SERPINA3) showed no significant associations.

Conclusions

There is a likely genetic basis to sporadic IAs. However, the evidence base is small when compared against other complex disorders.

Nationwide survey of antihypertensive treatment for acute intracerebral hemorrhage in Japan

Acute hypertension is associated with hematoma enlargement and poor clinical outcomes in patients with intracerebral hemorrhage (ICH). However, the method of controlling blood pressure (BP) during the acute phase of ICH remains unknown. The aim of this study is to show current strategies about this issue in Japan. Questionnaires regarding antihypertensive treatment (AHT) strategies were sent to neurosurgeons, neurologists and others responsible for ICH management in 1424 hospitals. Of 600 respondents, 550 (92%) worked at hospitals wherein acute ICH patients are managed and 548 (99.6%) of them agreed with the application of AHT within 24 h of ICH onset. Most answered that the systolic BP threshold for starting AHT was 180 mm Hg (36%) or 160 mm Hg (31%), which differed significantly between neurosurgeons (median, 160 mm Hg) and neurologists/others (180 mm Hg, P<0.001). The goal of lowering systolic BP was to reach a maximum of 140, 150 or 160 mm Hg according to 448 respondents (82%) and 209 (38%) intensively lowered systolic BP to <or=140 mm Hg. Nicardipine was the first choice of intravenous drug for 313 (57%) and the second choice for 146 respondents (27%). However, 141 (26%) thought that nicardipine is inappropriate mainly because of a conflict with a description of contraindications on the official Japanese label for this drug. In conclusion, the present Japanese respondents, especially neurosurgeons, lower BP more aggressively than recommended in domestic and Western guidelines for managing acute ICH patients. Nicardipine was the most frequent choice of antihypertensive agent.

The genetics of primary haemorrhagic stroke, subarachnoid haemorrhage and ruptured intracranial aneurysms in adults

Background

The genetic basis of haemorrhagic stroke has proved difficult to unravel, partly hampered by the small numbers of subjects in any single study. A meta-analysis of all candidate gene association studies of haemorrhagic stroke (including ruptured subarachnoid haemorrhage and amyloid angiopathy-related haemorrhage) was performed, allowing more reliable estimates of risk.

Methods

A systematic review and meta-analysis of all genetic studies in haemorrhagic stroke was conducted. Electronic databases were searched until and including March 2007 for any candidate gene in haemorrhagic stroke. Odds ratio (OR) and 95% confidence intervals (CI) were determined for each gene disease association using fixed and random effect models.

Results

Our meta-analyses included 6,359 cases and 13,805 controls derived from 55 case-control studies, which included 12 genes (13 polymorphisms). Statistically significant associations with haemorrhagic stroke were identified for those homozygous for the ACE/I allele (OR, 1.48; 95% CI, 1.20–1.83; p = 0.0003) and for the 5G allele in the SERPINE1 4G/5G polymorphism (OR, 1.42; 95% CI, 1.03–1.96; p = 0.03). In addition, both &b.epsi;2 and &b.epsi;4 alleles of APOE were significantly associated with lobar haemorrhage (OR, 1.81; 95% CI, 1.26–2.62; p = 0.002 and OR, 1.49; 95% 1.08–2.05; p = 0.01 respectively). Furthermore, a significant protective association against haemorrhagic stroke was found for the factor V Leiden mutation (OR, 0.30; 95% CI, 0.10–0.87; p = 0.03).

Conclusion

Our data suggests a genetic contribution to some types of haemorrhagic stroke, with no overall responsible single gene but rather supporting a polygenic aetiology . However, the evidence base is smaller compared to ischaemic stroke. Importantly, for several alleles previously found to be associated with protection from ischaemic stroke, there was a trend towards an increased risk of haemorrhagic stroke.

Functional outcome at 6 months in surgical treatment of spontaneous supratentorial intracerebral haemorrhage

A prospective cohort study was done to evaluate the role of surgery in patients with spontaneous supratentorial intracerebral haemorrhage (SICH) and to identify predictors of outcome including the use of invasive regional cortical cerebral blood flow (rCoBF) and microdialysis. Surgery consisted of craniotomy or decompressive craniectomy. The ventriculostomy for intracranial pressure (ICP) monitoring and drainage and regional cortical cerebral blood flow (rCoBF) and microdialysis were performed in all subjects. Pre and post operative information on subjects were collected. The study end points was functional outcome at 6 months based on a dichotomised Glasgow Outcome Scale (GOS).The selected clinical, radiological, biochemical and treatment factors that may influence the functional outcome were analysed for their significance. A total of 36 patients were recruited with 27(75%) patients had Glasgow Coma Score (GCS) between 5 to 8 on admission and 9(25%) were admitted with GCS of 9. At 6 months, 86 % had a poor or unfavourable outcome (GOS I-III) and 14% had good or favourable outcome (GOS IV-V). The mortality rate at 6 months was 55%. Univariate analysis for the functional outcome identified 2 significant variables, the midline shift (p=0.013) and mean lactate:pyruvate ratio (p=0.038). Multivariate analysis identified midline shift as the single significant independent predictor of functional outcome (p=0.013).Despite aggressive regional cortical cerebral blood flow (rCoBF) and microdialysis study for detection of early ischemia, surgical treatment for spontaneous intracerebral haemorrhage only benefited a small number of patients in terms of favourable outcome (14%) and in the majority of patients (86%), the outcome was unfavourable. Patients with midline shift > 5mm has almost 21 times higher chances (adj) OR 20.8 of being associated with poor outcome (GOS I-III).

Epidemiologic predictors of 30-day survival in cerebellar hemorrhage

BACKGROUND

Outcome after cerebellar hemorrhage is relatively poorly understood.

OBJECTIVES

To describe cerebellar hemorrhage and to establish if there were epidemiologic risk factors associated with early mortality.

METHODS

Computerized records were searched to identify intracerebral hemorrhage (ICD-9-CM code 431) from 1986 to 1996 at 2 hospitals. Charts were abstracted using a standardized protocol. The provincial vital statistics registry was used to confirm mortality data. A multivariable logistic regression model was developed to identify predictors of 30-day mortality.

RESULTS

Of 629 identified cases of intracerebral hemorrhage, 79 (12.5%) were cerebellar. The 30-day mortality was 41.7%. Approximately one third (31.7%) had an identifiable underlying cause. The odds of survival at 30 days was significantly reduced (odds ratio = 0.24; 95% confidence interval, 0.08 to 0.74) if the hemorrhage was caused by an identifiable underlying cause.

CONCLUSIONS

Cerebellar hemorrhage with an underlying cause is more likely to be fatal than idiopathic or hypertensive cerebellar hemorrhage.

Reducing the risk of ICH enlargement

Intracerebral hemorrhage (ICH) comprises 15% of all strokes, and carries the highest risk of mortality and poor long-term outcome. ICH has long been recognized as the least treatable form of stroke, and hematoma volume as the strongest single predictor of mortality and outcome. CT-based studies have found that early substantial hematoma expansion occurs in 18-38% of patients initially scanned within 3 h of symptom onset. This finding is associated with early neurological deterioration and an increased risk of poor outcome. Ultra-early hemostatic therapy might be beneficial in preventing hematoma growth, resulting in improved mortality and neurological function. Recombinant activated factor VII (rFVIIa) promotes local hemostasis in the presence or absence of coagulopathy at sites of vascular injury, and is a promising treatment for arresting active bleeding in ICH. The safety and feasibility of this approach was confirmed in a phase IIb randomized, double-blind, placebo-controlled, dose-ranging trial of 399 patients with non-coagulopathic ICH. Administration of rFVIIa within 4 h of ICH onset resulted in a significant reduction of hematoma expansion at 24 h, and reduced mortality and improved functional outcome at 90 days. A confirmatory phase III trial (The FAST Trial) to confirm these results will complete enrollment in the end of 2006.

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.

Is hypertension a more frequent risk factor for deep than for lobar supratentorial intracerebral haemorrhage?

OBJECTIVE

To determine whether evidence from observational studies supports the widely held belief that hypertension is more commonly a risk factor for deep than for lobar supratentorial intracerebral haemorrhage.

METHODS

Studies comparing the frequency of hypertension as a risk factor for deep versus lobar supratentorial intracerebral haemorrhage, excluding haemorrhages with identified secondary causes, were identified and subjected to a meta-analysis. The effects of predefined methodological quality criteria on the results were assessed and other sources of bias were considered.

RESULTS

The pooled result from all 28 included studies (about 4000 patients) found hypertension to be about twice as common in patients with deep as in those with lobar haemorrhage (odds ratio (OR) 2.10, 95% confidence interval (95% CI) 1.82 to 2.42), but there was significant heterogeneity between studies. The pooled OR was less extreme for studies that used a pre-stroke definition of hypertension, were population based or included first-ever strokes only. In the three studies meeting all criteria (601 patients), deep haemorrhage was associated with a smaller, statistically significant excess of hypertension (OR 1.50, 95% CI 1.09 to 2.07). The OR for studies confined to younger patients seemed to be more extreme (12.32, 95% CI 6.13 to 24.77), but none of these studies fulfilled our methodological quality criteria. Additional, unquantified sources of bias included uncertainty about whether those doctors reporting brain scans were blind to hypertension status, uncertain reliability of the classification of haemorrhage location and variable rates of investigation for secondary causes.

CONCLUSIONS

An excess of hypertension was found in patients with deep versus lobar intracerebral haemorrhages without an identified secondary cause, but this may be due to residual, unquantified methodological biases.

Intracerebral Hemorrhage

INTRODUCTION

Intracerebral hemorrhage (ICH) occurs from the rupture of small vessels into the brain parenchyma and accounts for approximately 10% of all strokes in the United States, and carries with it a significantly high morbidity and mortality.

SUMMARY

This article reviews the course and management of ICH. The most common chronic vascular diseases that lead to ICH are chronic hypertension and cerebral amyloid angiopathy. Additional factors that predispose to ICH include vascular malformations, chronic alcohol use, hypocholesterolemia, and use of anticoagulant medications. The understanding of mechanisms leading to ICH has advanced significantly, but questions regarding site predilection and timing of spontaneous hemorrhage still remain. Management in the acute setting is first focused on reducing hematoma expansion. Although no specific therapy has yet been proven effective, promising agents, particularly recombinant Factor VIIa, are on the horizon. Subsequent care is focused on controlling hemostasis, hemodynamics, and intracranial pressure in efforts to minimize secondary brain injury.

CONCLUSION

The morbidity and mortality associated with ICH remain high despite recent advances in our understanding of the clinical course of ICH. Novel preventive and acute treatment therapies are needed and may be on the horizon.

Epidemiology of transient ischemic attack and ischemic stroke in patients with underlying cardiovascular disease

It is estimated that 15 to 30% of ischemic strokes are cardioembolic in origin, and that atrial fibrillation, valvular heart disease, coronary artery disease, congestive heart failure, and myocardial infarction are significant risk factors for stroke, which underscores the importance for cardiologists to understand this condition. The high incidence and substantial cost of stroke justify aggressive treatment of stroke risk factors, especially in the elderly, diabetic, and black populations, and in patients who have had an initial stroke. Antiplatelet therapy and administration of oral anticoagulants have both been shown to have a substantial impact on stroke in specified populations at risk.

Antiplatelet agents and anticoagulants for hypertension

BACKGROUND

Although elevated systemic blood pressure results in high intravascular pressure, the main complications, coronary heart disease (CHD), ischaemic strokes and peripheral vascular disease (PVD), are related to thrombosis rather than haemorrhage. Some complications related to elevated blood pressure, heart failure or atrial fibrillation, are themselves associated with stroke and thromboembolism. It therefore seemed plausible that use of antithrombotic therapy may be particularly useful in preventing thrombosis-related complications of elevated blood pressure.

OBJECTIVES

To conduct a systematic review of the role of antiplatelet therapy and anticoagulation in patients with blood pressure, including those with elevations in both systolic and diastolic blood pressure, isolated elevations of either systolic or diastolic blood pressure, to address the following hypotheses: (i) antiplatelet agents reduce total deaths and/or major thrombotic events when compared to placebo or other active treatment; and (ii) oral anticoagulants reduce total deaths and/or major thromboembolic events when compared to placebo or other active treatment.

SEARCH STRATEGY

Reference lists of papers resulting from this search, electronic database searching (MEDLINE, EMBASE, DARE), and abstracts from national and international cardiovascular meetings were studied to identify unpublished studies. Relevant authors of these studies were contacted to obtain further data.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in patients with elevated blood pressure were included if they were of at least 3 months in duration and compared antithrombotic therapy with control or other active treatment.

DATA COLLECTION AND ANALYSIS

Data were independently collected and verified by two reviewers. Data from different trials were pooled where appropriate.

MAIN RESULTS

The ATC meta-analysis of antiplatelet therapy for secondary prevention in patients with elevated blood pressure reported an absolute reduction in vascular events of 4.1% as compared to placebo. Data on the patients with elevated blood pressure from the 29 individual trials included in this meta-analysis was requested but could not be obtained. Three additional trials met the inclusion criteria and are reported on here. Acetylsalicylic acid (ASA) did not reduce stroke or 'all cardiovascular events' compared to placebo in primary prevention patients with elevated blood pressure and no prior cardiovascular disease. Based on one large trial (HOT trial), ASA taken for 5 years reduced myocardial infarction (ARR, 0.5%, NNT 200 for 5 years), increased major haemorrhage (ARI, 0.7%, NNT 154), and did not reduce all cause mortality or cardiovascular mortality. There was no significant difference between ASA and clopidogrel for the composite endpoint of stroke, myocardial infarction or vascular death in one trial (CAPRIE 1996). In two small trials warfarin alone or in combination with ASA did not reduce stroke or coronary events.

REVIEWERS' CONCLUSIONS

For primary prevention in patients with elevated blood pressure, anti-platelet therapy with ASA cannot be recommended since the magnitude of benefit, a reduction in myocardial infarction, is negated by a harm of similar magnitude, an increase in major haemorrhage. For secondary prevention in patients with elevated blood pressure (ATC meta-analysis: APTC 1994) antiplatelet therapy is recommended because the magnitude of the absolute benefit is many times greater. Warfarin therapy alone or in combination with aspirin in patients with elevated blood pressure cannot be recommended because of lack of demonstrated benefit. Glycoprotein IIb/IIIa inhibitors as well as ticlopidine and clopidogrel have not been sufficiently evaluated in patients with elevated blood pressure. Further trials of antithrombotic therapy with complete documentation of all benefits and harms are required in patients with elevated blood pressure.

Primary intracerebral haemorrhage--clinical and radiologic predictors of survival and functional outcome

PURPOSE

Primary intracerebral haemorrhage (ICH) is a common and devastating disorder that often results in long-term disability. This review examines the literature on predictors of survival and long-term functional outcome after ICH.

METHOD

Medical literature review.

RESULTS

Numerous clinical and radiologic variables have been shown to be associated with survival and functional recovery following ICH. These include patient age and gender, lesion size and location, initial level of consciousness, presence of intraventricular haemorrhage, hydrocephalus, and mass effect. Studies have employed a variety of outcome measures including survival and functional recovery.

CONCLUSIONS

Clinical and radiologic findings following ICH may assist rehabilitation specialists as they develop treatment goals, anticipate long-term patient care needs, and educate and train caregivers.

Ethnicity and peripheral arterial disease

INTRODUCTION

the prevalence of peripheral arterial disease (PAD) is relatively well defined for the Caucasian population. Given the susceptibility of Asians and Afro-Caribbeans to coronary heart disease and stroke respectively, and the high prevalence of cardiovascular risk factors in both groups, one would expect a high prevalence of peripheral arterial disease.

METHODS

a search of MEDLINE (1966-2002) was undertaken for studies on the incidence and prevalence of PAD, abdominal aortic aneurysms (AAA) and cerebrovascular disease in different ethnic groups.

RESULTS

there are very few population-based prevalence studies assessing PAD, AAA or cerebrovascular disease in non-Caucasians. A review of hospital-based series demonstrates different patterns of PAD between ethnic groups. Blacks and Asians have a tendency towards more distal occlusive disease and AAA appear to be predominantly a disease of Caucasians. It is not clear whether these studies provide a true representation of the prevalence of arterial disease in various ethnic groups or are the result of an unmet health care need.

CONCLUSIONS

further studies are required to establish the prevalence, natural history and response to treatment of PAD, AAA and cerebrovascular disease in non-Caucasians. Only when this has been achieved, can clinically and cost-effective health care be delivered to affected individuals from different ethnic groups.

Current intracerebral haemorrhage management

Primary intracerebral haemorrhage (ICH) refers to spontaneous bleeding from intraparenchymal vessels. It accounts for 10-20% of all strokes, with higher incidence rates amongst African and Asian populations. The major risk factors are hypertension and age. In addition to focal neurological findings, patients may present with symptoms of elevated intracranial pressure. The diagnosis of ICH can only be made through neuro-imaging. A CT scan is presently standard, although MRI is increasingly important in the evaluation of acute cerebrovascular disease. A significant proportion of intracerebral haematomas expand in the first hours post-ictus and this is often associated with clinical worsening. There is evidence that the peri-haematomal region is compromised in ICH. This tissue is oedematous, although the precise pathogenesis is controversial. An association between elevated arterial pressure and haematoma expansion has been reported. Although current guidelines recommend conservative management of arterial pressure in ICH, an acute blood pressure lowering trial is overdue. ICH is associated with a high early mortality rate, although a significant number of survivors make a functional recovery. Current medical management is primarily aimed at prevention of complications including pneumonia and peripheral venous thromboembolism. Elevated intracranial pressure may be treated medically or surgically. Although the latter definitively lowers elevated intracranial pressure, the optimal patient selection criteria are not clear. Aggressive treatment of hypertension is essential in the primary and secondary prevention of ICH.

Stroke: a review with an African perspective

The frequency of stroke and stroke-associated mortality are higher in Blacks than in other races. Several of the known risk factors for stroke, such as hypertension, diabetes and obesity, are more common in Blacks than Whites, and sickle-cell disease and HIV infection are stroke risk factors with particular relevance to Africans. Although the facilities for accurate stroke diagnosis and classification are unavailable in most parts of Africa, careful analysis of the clinical features can minimize the rates of misdiagnosis and misclassification. The high levels of stroke-attributable morbidity and mortality observed in Africans could be markedly reduced by instituting primary and secondary preventive measures and by educating health-care professionals on stroke-management strategies.

Stroke in African Americans

There is an excess burden of cerebrovascular disease in African Americans. This article will define possible reasons for excess stroke risk, review racial differences in stroke subtype and stroke prevention programs in the African American Community, and delineate sequelae of stroke. The authors provide insights about stroke prevention in African Americans and highlight challenges to reduce the burden of cerebrovascular disease in this high-risk group.

Long-term outcome after medical reversal of transtentorial herniation in patients with supratentorial mass lesions

OBJECTIVE

To determine the short- and long-term outcomes after successful reversal of transtentorial herniation by medical treatment. Although it has been recognized that aggressive medical management can reverse transtentorial herniation, it is believed that overall outcome in such patients is poor.

DESIGN

Prospective cohort study.

SETTING

Neurocritical care unit of a university hospital.

PATIENTS

A total of 28 consecutive patients who underwent an episode of transtentorial herniation (defined as decrease in level of consciousness accompanied by pupillary dilation) secondary to a supratentorial mass lesion followed by successful reversal.

INTERVENTION

Herniation was reversed by using a combination of hyperventilation, mannitol and hypertonic saline.

MEASUREMENTS AND MAIN RESULTS

The following outcomes were analyzed: risk of second herniation, radiologic evidence of structural damage or vascular compromise related to herniation on post-herniation computed tomographic scan, in-hospital mortality, and long-term functional outcome using Rankin score and Barthel index. A total of 32 episodes of transtentorial herniations were reversed in 28 patients during a 14-month period. The most common precipitating cause were edema (n = 23) or new/expanding intracerebral hematoma (n = 5). After first reversal of transtentorial herniation in 28 patients, a second herniation episode was observed in 16 patients after a mean interval of 88.2 hrs (range, 23-432 hrs); four were successfully reversed. On follow-up computed tomographic scan, hypodense lesion in midbrain (n = 6), temporal lobe contusion (n = 2), posterior cerebral artery (n = 3), and middle cerebral artery (n = 1) infarction were visualized in a minority of patients. The in-hospital mortality was 60% (n = 15) with brain death being the cause of death in 13 patients; care was withdrawn in eight patients. Second episode of herniation (p = .002) and midbrain involvement during herniation (p = .02) were associated with in-hospital mortality. During a mean follow-up period of 11.4+/-4.2 months, two patients died of cerebral neoplasm and human immunodeficiency virus-related sepsis, respectively. Of the 11 survivors, 7 were functionally independent (Rankin score <3 and Barthel index >60).

CONCLUSIONS

Although mortality after transtentorial herniation is high, we found a prominent potential for meaningful recovery with aggressive medical reversal of transtentorial herniation. Our study implies that timely medical intervention for reversing transtentorial herniation can result in preservation of neurologic function.

Hypertension-induced organ damage in African Americans: transforming growth factor-beta(1) excess as a mechanism for increased prevalence

Hypertension is prevalent world-wide, and it affects over 50 million individuals in the United States alone. African Americans (blacks) have a high prevalence of hypertension, develop it at an earlier age, and suffer excessively from severe or malignant hypertension. They also have a high prevalence of target organ damage attributable to hypertension, including left ventricular hypertrophy, stroke, end-stage renal disease (ESRD) and coronary artery disease. Hypertensive nephrosclerosis is particularly more prevalent in blacks compared to whites, and there is evidence that factors in addition to elevated blood pressure contribute to its pathogenesis. Transforming growth factor-beta 1 (TGF-beta1) is a fibrogenic cytokine that has been implicated in the development and progression of experimental and human renal diseases. We have demonstrated that blacks with ESRD have higher circulating levels of TGF-beta1 protein compared to whites with ESRD. We have also found that hyperexpression of TGF-beta1 is more frequent in blacks with hypertension than in whites. We propose that TGF-beta1 hyperexpression may be an important mediator of hypertension and hypertensive nephrosclerosis. We hypothesize also that the increased frequency of TGF-beta1 hyperexpression may contribute to the excess burden of ESRD in blacks. Based on our hypotheses, and the observations that angiotensin-converting enzyme inhibitors and angiotensin receptor antagonists reduce angiotensin II-mediated stimulation of TGF-beta1 production, we propose that treatment with these agents might be efficacious in preventing or slowing the progression of target organ damage in hypertensive blacks.

Diffusion-weighted magnetic resonance imaging in the early evaluation of corticospinal tract injury to predict functional motor outcome in patients with deep intracerebral hemorrhage

OBJECT

Diffusion-weighted (DW) magnetic resonance imaging was used to visualize corticospinal tract injury in patients with deep intracerebral hemorrhage (ICH), and the results were used to predict motor impairment of the extremities.

METHODS

Twenty-eight patients with deep ICH (17 men and 11 women, mean age 58+/-14 years) were examined. The volume of the ICH was assessed on initial computerized tomography scans. Twelve patients had ICH volumes of 40 ml or more and were treated surgically, and 16 patients who had an ICH volume of less than 40 ml were treated medically. Initial corticospinal tract injury was classified into four grades according to the anatomical relationship between the corticospinal tract and the ICH on DW images. Motor impairment of both the upper and lower extremities was assessed at admission and 1 month poststroke by using the National Institutes of Health Stroke Scale. The extent of correlation was determined between motor impairment and corticospinal tract injury. Initial corticospinal tract injury was not correlated with the impairment of extremities at admission but was closely correlated with motor impairment of the upper (r = 0.843, p < 0.001) and lower (r = 0.868, p < 0.001) extremities at 1 month poststroke. Impairment of the upper extremities correlated better with anterior than with posterior corticospinal tract injury (r = 0.911 compared with r = 0.600), and impairment of the lower extremities correlated better with posterior than with anterior injury (r = 0.890 compared with r = 0.787).

CONCLUSIONS

Early evaluation of corticospinal tract injury based on DW imaging can provide predictive value for motor functional outcome in patients with deep ICH.

Racial differences in the incidence of intracerebral hemorrhage: effects of blood pressure and education

OBJECTIVE

To determine the relative risk (RR) of intracerebral hemorrhage (ICH) among African Americans compared with that among whites.

METHODS

Data from the First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study were used to determine the incidence of ICH (n = 78) in 10,851 whites and 1,802 African Americans during a 20-year follow-up period. Cox proportional hazards analyses were used to determine the RR of ICH among African Americans compared with that among whites.

RESULTS

The estimated annual incidence of ICH was 50 per 100,000 among African Americans and 28 per 100,000 among whites. The age- and sex-adjusted RR for ICH among African Americans was 1.9 (95% confidence interval [CI], 1.1 to 3.2). With the addition of systolic blood pressure and educational attainment to the Cox proportional hazards model, the RR decreased to 1.6 (95% CI, 0.9 to 2.7). The adjustment for additional cerebrovascular disease risk factors did not change this risk estimate appreciably.

CONCLUSIONS

Compared with whites, African Americans have a twofold increased risk for ICH. Most of this risk may be explained by differences in educational attainment and systolic blood pressure. Unless additional efforts are undertaken to reduce racial differences in the prevalence of stroke risk factors, mainly systolic blood pressure and socioeconomic status, the African American-white disparities in the risk for ICH will likely continue.

Pharmacologic reduction of mean arterial pressure does not adversely affect regional cerebral blood flow and intracranial pressure in experimental intracerebral hemorrhage

OBJECTIVE

To determine the effect of mean arterial pressure (MAP) reduction on regional cerebral blood flow and intracranial pressure (ICP) in intracerebral hemorrhage. We tested the hypothesis that there is ischemia in the perihematoma region after intracerebral hemorrhage, which can be exacerbated by a pharmacologic reduction of MAP.

DESIGN

Prospective, controlled, laboratory trial.

SETTING

Animal research laboratory.

SUBJECTS

Eighteen mongrel dogs, weighing 15 to 25 kg.

INTERVENTIONS

We introduced intracerebral hemorrhage in 12 anesthetized dogs by autologous blood injection under arterial pressure in the deep white matter adjacent to the left caudate region. We measured serial regional cerebral blood flow using radiolabeled microspheres in animals with two different volumes of injected blood (2.8 mL [Group A, n = 6] and 4.4 mL [Group B, n = 6]) and compared them with control animals (n = 6). Intravenous labetalol was administered 90 mins after administration of hematoma, while maintaining cerebral perfusion pressure >65 mm Hg. Regional cerebral blood flow measurements were repeated 10 and 30 mins after labetalol administration. MAP and ICP were monitored continuously using intra-arterial and cisterna magna catheters, respectively.

MEASUREMENTS AND MAIN RESULTS

Compared with control animals, significant elevation in ICP was observed in Groups A and B and elevation in MAP was observed in Group B at 45 mins after injection of blood. These hemodynamic alterations were not accompanied by any significant differences in regional cerebral blood flow in any group. Administration of labetalol resulted in a decrease in MAP (mm Hg+/-SEM) in Groups A (119.0+/-9.2 to 103.0+/-9.1) and B (124.5+/-7.4 to 100.5+/-4.8) and controls (103.5+/-4.3 to 85.0+/-8.0). No differences were observed in regional cerebral blood flow after MAP reduction in both Groups A and B compared with controls in regions around or distant to the hematoma. There were no changes in ICP in Groups A and B both at 10 and 30 mins after reduction in MAP compared with pretreatment values.

CONCLUSIONS

In our model, pharmacologic reduction of MAP within the normal autoregulatory limits of cerebral perfusion pressure, 90 mins after onset, had no adverse effect on ICP and regional cerebral blood flow in regions around or distant to the hematoma. These results support the controlled use of antihypertensive treatment in intracerebral hemorrhage in the initial time period.