A population-based study of the incidence and prognosis of lacunar stroke

Progressive lacunar stroke: review of mechanisms, prognostic features, and putative treatments

Lacunar stroke is generally considered to have a fair outcome. However 20-30% of patients with lacunar stroke worsen neurologically in hours or days after onset, reaching eventually an unexpectedly severe disability status. In the field of acute stroke, progressive lacunar stroke remains an important unresolved practice problem, because as yet no treatment does exist proven to prevent or halt progression. Pathophysiology of progression is yet incompletely understood. Hemodynamic factors, extension of thrombosis, excitotoxicity, and inflammation, have been proposed as possible mechanisms of progression. A few clinical studies also aimed at establishing presentation features that may help identifying patients at risk of deterioration. In this paper, we review hypothesized mechanisms of lacunar stroke progression and possible markers of early deterioration. Moreover, based on putative mechanisms and suggestions from reported evidence, we propose a few treatments that seem worthy to be tested by randomized clinical trials.

Risk factors and outcome of patients with symptomatic intracranial stenosis presenting with lacunar stroke

BACKGROUND AND PURPOSE

We hypothesized that patients with intracranial stenosis with lacunar stroke presentations would face lower risks of recurrent stroke than those with index nonlacunar strokes, and that their recurrent strokes would predominantly be lacunar.

METHODS

We analyzed subjects enrolled with an index stroke into the Warfarin Aspirin Symptomatic Intracranial Disease (WASID) trial. The index stroke was classified as lacunar or nonlacunar. The primary end point was recurrent ischemic stroke. Cox proportional hazard models were generated with stratification for severity of stenosis.

RESULTS

Three hundred forty-seven subjects were enrolled after an index stroke; 38 were lacunar and 309 were nonlacunar. Over a mean follow-up of 1.8 years, there was no significant difference in stroke recurrence between patients whose index stroke was lacunar (7 of 38 [18%]) versus nonlacunar (69 of 309 [22%]; hazard ratio, 0.79; 95% CI, 0.36-1.71). Furthermore, no significant differences were found when groups were stratified by 50% to 69% stenosis (hazard ratio, 0.50; 95% CI, 0.12-2.1) and ≥ 70% stenosis (hazard ratio, 0.87; 95% CI, 0.34-2.2). Of the 7 recurrent strokes in patients whose index stroke was lacunar, all 7 were nonlacunar and 3 were in the territory of the stenotic artery.

CONCLUSIONS

In patients with symptomatic intracranial stenosis, the risk of recurrent stroke was similar in patients who presented with lacunar and nonlacunar strokes, and recurrent strokes in patients presenting with lacunar stroke were typically nonlacunar. These findings suggest that the pathophysiology of these strokes is related to the stenosis rather than small vessel disease. Patients presenting with lacunar strokes should be included in trials investigating secondary prevention for symptomatic intracranial stenosis.

Small vessel cerebrovascular disease: the past, present, and future

Brain infarction due to small vessel cerebrovascular disease (SVCD)-also known as small vessel infarct (SVI) or "lacunar" stroke-accounts for 20% to 25% of all ischemic strokes. Historically, SVIs have been associated with a favorable short-term prognosis. However, studies over the years have demonstrated that SVCD/SVI is perhaps a more complex and less benign phenomenon than generally presumed. The currently employed diagnostic and therapeutic strategies are based upon historical and contemporary perceptions of SVCD/SVI. What is discovered in the future will unmask the true countenance of SVCD/SVI and help furnish more accurate prognostication schemes and effective treatments for this condition. This paper is an overview of SVCD/SVI with respect to the discoveries of the past, what is known now, and what will the ongoing investigations evince in the future.

Epidemiology of stroke in Italy

This study reviews available data on stroke epidemiology in Italy. Data were identified through Medline/PubMed, Embase, and from reference lists, related articles, and citation lists of each of the retrieved papers. Nineteen papers were considered, referring to selected stroke-registers performed in seven different geographical areas: Acquaviva-Casamassima county, Aeolian Islands, Aosta district, Belluno district, L'Aquila district, Trasimeno area, and Vibo Valentia district. Registers covered a total population of 2 262 940 people, with a hospitalization rate from 82% to 98%. The mean age at stroke onset was 74·6 ± 1·1 years, 72·3 years in men and 76·6 years in women. Among all strokes: • 67·3-82·6% were classified ischemic • 9·9-19·6% as primary intracerebral hemorrhage • 1·6-4·0% as sub-arachnoid hemorrhage, and • 1·2-17·7% as undetermined. Annual incidence rates standardized to the Italian population ranged from 175/1 00 000 to 360/1 00 000 in men and from 130/1 00 000 to 273/1 00 000 in women. Thirty-day case-fatality rates for all strokes ranged from 18·1% to 33·0% while one-year case-fatality rates ranged from 37·9% to 40·2%. Data from selected Italian registers on stroke incidence and case-fatality indicate the great burden of the disease on our national healthcare system. The continuous implementation of preventive strategies, either population-based or addressed to the single patient at a high risk of stroke, is important to reduce the burden of the disease.

Quantitative EEG in ischemic stroke: correlation with infarct volume and functional status in posterior circulation and lacunar syndromes

OBJECTIVE

The significant impact of stroke on health care results in an unmet need for efficient stroke care in resources limited environments. Practical, inexpensive and easy to obtain predictive EEG parameters have been suggested in anterior circulation syndromes. We investigated whether EEG parameters are of additional predictive value with regard to lesion volume and short-term functional outcome in lacunar (LACS) and posterior circulation (POCS) syndromes of presumed ischemic origin.

METHODS

Sixty (60) patients presenting with LACS or POCS were incrementally included. EEG parameters were correlated with volume of ischemia and functional status. Predictive values for definite stroke and unfavourable outcome were calculated using receiver operating characteristic (ROC) curves and logistic regression modelling.

RESULTS

The pairwise derived brain symmetry index (pdBSI) emerged as independent predictor for definite stroke in patients presenting with LACS and POCS (odds ratio (OR) 2.69, 95% confidence interval (CI) 1.24-5.82, p=0.012) and in patients with a National Institutes of Health Stroke Scale (NIHSS) score of 0 at EEG recording (OR 7.67, 95% CI 1.24-47.32, p=0.026). In ROC analysis, the (delta+theta)/(alpha+beta) ratio (DTABR) predicted unfavourable outcome at day 7 with an accuracy of 83% in LACS but not in POCS. In logistic regression, unfavourable outcome in LACS was predicted by nominal NIHSS with marginal significance (OR 1.84, 95% CI 1.00-3.37, p=0.05), while in categorical modelling, DTABR>2.4 displayed a statistically significant ominous odd ratio of 13.00 (95% CI 1.11-152.35, p=0.041) with identical predicted and observed values.

CONCLUSIONS

EEG may be of additional value by confirming or excluding definite stroke after resolution of symptoms in lacunar and posterior circulation syndromes of presumed ischemic origin and prognosticating short-term functional status in lacunar syndrome.

SIGNIFICANCE

These findings may have an impact on stroke care.

Prevalence of silent myocardial ischemia in single and multiple lacunar infarcts and large vessel disease stroke

BACKGROUND AND PURPOSE

The relationships between single (SLI) and multiple lacunar infarcts (MLI) and occult coronary artery disease (CAD) have not yet been sufficiently evaluated. We aimed to investigate the prevalence of silent CAD in patients with SLI, MLI and large vessel disease (LVD) stroke, and to identify factors associated with its presence.

METHODS

We enrolled 125 patients who had suffered their first non-cardioembolic ischemic stroke but had no documented history of CAD. According to their pathologies, these patients were assigned to one of three groups: MLI (n=21), SLI (n=50) or LVD (n=54). Asymptomatic CAD was detected by myocardial perfusion SPECT imaging.

RESULTS

Silent CAD was detected in 40 patients (32% of the total); of those that experienced CAD, 15 (30%) were from the SLI group, 7 (33%) had MLI, and 18 (33%) had an LVD stroke. Differences between the groups were not significant. During a median follow-up of 48 months, the overall stroke recurrence was 8.8%; the stroke recurrence rates for each subgroup were 6% in patients with SLI, 7% in LVD and 19% in MLI. Mortality was higher in patients from the MLI and LVD groups (26% and 14%, respectively) than in those from the SLI group (6%; p=0.02). We found no relationships between the various risk factors and silent CAD.

CONCLUSIONS

In this exploratory study, SPECT imaging results revealed that the prevalence of abnormal myocardial perfusion was similar in patients with either single or multiple lacunar infarcts and those that had experienced large vessel disease stroke.

Differing risk factor profiles of ischemic stroke subtypes: evidence for a distinct lacunar arteriopathy?

BACKGROUND AND PURPOSE

Differences in risk factor profiles between lacunar and other ischemic stroke subtypes may provide evidence for a distinct lacunar arteriopathy, but existing studies have limitations. We overcame these by pooling individual data on 2875 patients with first-ever ischemic stroke from 5 collaborating prospective stroke registers that used similar, unbiased methods to define risk factors and classify stroke subtypes.

METHODS

We compared risk factors between lacunar and nonlacunar ischemic strokes, altering the comparison groups in sensitivity analyses, and incorporated these data into a meta-analysis of published studies.

RESULTS

Unadjusted and adjusted analyses gave similar results. We found a lower prevalence of cardioembolic source (adjusted odds ratio, 0.33; 95% CI, 0.24 to 0.46), ipsilateral carotid stenosis (odds ratio, 0.21; 95% CI, 0.14 to 0.30), and ischemic heart disease (odds ratio, 0.75; 95% CI, 0.58 to 0.97) in lacunar compared with nonlacunar patients but no difference for hypertension, diabetes, or any other risk factor studied. Results were robust to sensitivity analyses and largely confirmed in our meta-analysis.

CONCLUSIONS

Hypertension and diabetes appear equally common in lacunar and nonlacunar ischemic stroke, but lacunar stroke is less likely to be caused by embolism from the heart or proximal arteries, and the lower prevalence of ischemic heart disease in lacunar stroke provides additional support for a nonatherosclerotic arteriopathy causing many lacunar ischemic strokes. Our findings have implications for how clinicians classify ischemic stroke subtypes and highlight the need for additional research into the specific causes of and treatments for lacunar stroke.

Implications of immune system in stroke for novel therapeutic approaches

Each year, approximately 795,000 people suffer a new or recurrent stroke. About 610,000 of these are first attacks, and 185,000 are recurrent attacks. Currently, the only FDA approved treatment for ischemic stroke is the thrombolytic recombinant tissue plasminogen activator (Alteplase), which must be given within 4.5 h of stroke onset. Beyond this time, apoptotic and inflammatory processes greatly diminish the therapeutic benefits of current treatments. While there have been many experimental treatments for stroke that showed promising preclinical efficacy, these treatments have failed to show efficacy in clinical trials. In many of these cases, the preclinical animal studies did not model the clinical setting effectively. The injury that occurs following stroke is a dynamic process. To effectively treat stroke patients at clinically relevant timepoints, it is imperative to understand both the humeral and cell-mediated phenomena that occur throughout the body in response to ischemic injury over time. Promising experimental therapeutics designed to be given 1 to 2 days following stroke require both neuroprotective and anti-inflammatory properties in order to be efficacious.

Long-term prognosis of Chinese patients with a lacunar infarct associated with small vessel disease: a five-year longitudinal study

RATIONALE

Lacunar infarct associated with small vessel disease is a common stroke subtype in China and has a favorable short-term prognosis. Data on its long-term prognosis among Chinese patients are lacking.

AIMS

We aimed to study its long-term prognosis and predictors for poor outcomes.

DESIGN

We followed up to 75 consecutive Chinese stroke patients who had a lacunar infarct for a period of 5 years. Clinical outcomes with respect to mortality and recurrent stroke were noted. We evaluated baseline clinical and imaging predictors for such outcomes using the Cox regression analysis.

STUDY OUTCOMES

Sixteen (21.3%) patients died and 12 (16%) patients had recurrent stroke during follow-up. Twenty-one (28%) patients had combined events of either death and/or recurrent stroke. Univariate Cox regression analysis showed that age, literacy, National Institute of Health Stroke Scale, incident stroke/transient ischemic attack, and white matter lesion volume predicted survival, while, age, National Institute of Health Stroke Scale, systolic blood pressure, hyperhomocysteinemia, silent lacunes, microbleeds, and white matter lesion volume predicted recurrent stroke. Multivariate Cox regression analysis showed that National Institute of Health Stroke Scale (HR 1.25, 95% CI 1.05-1.48) and white matter lesion volume (HR 1.46, 95% CI 1.11-1.92) predicted combined events of mortality and/or recurrent stroke after age adjustment.

CONCLUSION

Approximately one in four patients either died and/or had recurrent stroke within 5 years after a lacunar infarct. Age, stroke severity, and volume of white matter lesion predict a poor long-term prognosis.

Lacunar stroke

Lacunar infarcts or small subcortical infarcts result from occlusion of a single penetrating artery and account for one quarter of cerebral infarctions. Patients with a lacunar infarct usually present with a classical lacunar syndrome (pure motor hemiparesis, pure sensory syndrome, sensorimotor stroke, ataxic hemiparesis or dysarthria-clumsy hand) and, less frequently, an atypical lacunar syndrome. Hypertension and diabetes mellitus are major risk factors for lacunar stroke. Lacunar infarcts show a paradoxical clinical course with a favorable prognosis in the short term, characterized by a low early mortality and reduced functional disability on hospital discharge, but with an increased risk of death, stroke recurrence and dementia in the mid- and long term. Asymptomatic progression of small-vessel disease is a typical feature of the lacunar infarcts. For this reason, lacunar infarction should be regarded as a potentially severe condition rather than a relatively benign disorder and, therefore, lacunar stroke patients require adequate and rigorous management and follow-up. Antiplatelet drugs, careful blood pressure control, the use of statins and modification of lifestyle risk factors are key elements in secondary prevention after lacunar stroke.

Transient ischemic attack before nonlacunar ischemic stroke in the elderly

BACKGROUND

Several studies suggest transient ischemic attack (TIA) may be neuroprotective against ischemic stroke analogous to preinfarction angina's protection against acute myocardial infarction. However, this protective ischemic preconditioning-like effect may not be present in all ages, especially among the elderly. The purpose of this study was to determine the neuroprotective effect of TIAs (clinical equivalent of cerebral ischemic preconditioning) to neurologic damage after cerebral ischemic injury in patients over 65 years of age.

METHODS

We reviewed the medical charts of patients with ischemic stroke for presence of TIAs within 72 hours before stroke onset. Stroke severity was evaluated by the National Institutes of Health Stroke Scale and disability by a modified Rankin scale.

RESULTS

We evaluated 203 patients (>or=65 years) with diagnosis of acute ischemic stroke and categorized them according to the presence (n = 42, 21%) or absence (n = 161, 79%) of TIAs within 72 hours of stroke onset. Patients were monitored until discharged from the hospital (length of hospital stay 14.5 +/- 4.8 days). No significant differences in the National Institutes of Health Stroke Scale and modified Rankin scale scores were observed between those patients with TIAs and those without TIAs present before stroke onset at admission or discharge.

CONCLUSION

These results suggest that the neuroprotective mechanism of cerebral ischemic preconditioning may not be present or functional in the elderly.

Trends in Incidence, Risk Factors, and Survival in Symptomatic Lacunar Stroke in Dijon, France, From 1989 to 2006

Background and Purpose— Lacunar infarcts are usually regarded as benign stroke, but population-based studies are required to assess the exact place of this stroke subtype in cerebrovascular pathology.

Methods— We evaluated trends in incidence rates, risk factor profiles, and survival rates in symptomatic lacunar stroke from a prospective population-based registry from 1989 to 2006.

Results— We recorded 2536 ischemic strokes. Among these, 715 (28%) were lacunar infarcts (354 men and 361 women). From 1989 to 2006, we observed a significant rise in the incidence of lacunar stroke in the 2 sexes considered together (relative risk, 1.02; 95% CI, 1.005 to 1.035; P =0.007), whereas the variation was not significant in either men or women when considered separately. Incidence rates significantly increased in young patients under 65 years old (relative risk, 1.049; 95% CI, 1.0175 to 1.0817; P =0.002). Concerning the distribution of cerebrovascular risk factors, lacunar stroke differed from nonlacunar stroke only with regard to the lower prevalence of a history of atrial fibrillation in the former ( P <0.001). For lacunar infarcts, survival rates were 96% at 1 month (95% CI, 0.94 to 0.97), 86% at 1 year (95% CI, 0.83 to 0.89), and 78% at 2 years (95% CI, 0.75 to 0.81) and were significantly higher than those for nonlacunar stroke (hazard ratio, 2.05; 95% CI, 1.70 to 2.47; P <0.001).

Conclusion— Our results suggest a significant increase in the incidence rates of lacunar stroke with a relatively good short-term prognosis in terms of survival. The association among hypertension, diabetes mellitus, and lacunar stroke was no stronger than the association between these 2 risk factors and nonlacunar stroke.

Cerebral small vessel disease: genetic risk assessment for prevention and treatment

Cerebrovascular disease is a major burden to individuals and their communities worldwide. Stroke is one of the leading causes of death and disability, and the prevention and treatment of stroke can be improved with a better understanding of its causation. Cerebral small vessel disease (SVD) is a subset of cerebrovascular disease, and has an equally large impact on an individual's quality of life. Although many risk factors are involved, we propose that genetics has a significant role in the pathogenesis of SVD through a complex interplay of environmental and multigenetic factors. Advances in molecular technology have enabled the human genome to be investigated both at a population and, more recently, an individual level. A better understanding of the molecular basis of SVD will enable the development of therapies to help in its prevention and treatment. This review assesses the molecular genetics underlying cerebral SVD.

Need for extensive diagnostic work-up for patients with lacunar stroke

OBJECTIVE

Small-vessel disease is the most frequent cause of lacunar stroke. The aims of this study were to evaluate: 1) alternative causes of lacunar stroke other than small-vessel disease; 2) functional outcome of lacunar strokes due to small vessel disease compared to lacunar strokes due to alternative causes.

METHODS

Consecutive patients with first-ever ischemic lacunar stroke were prospectively followed-up for at least 3 months. At discharge patients were divided into 2 groups: lacunar stroke due to small vessel disease (L-SVD) and lacunar stroke due to possible other etiologies (L-non SVD) (e. g. cardioembolism, atherosclerosis or other causes). Main outcome measures were the combined end point of death or disability (mRS >or= 3) and recurrent stroke at the end of follow-up.

RESULTS

535 patients with acute stroke were seen during the study period. Out of these, 196 patients (126 males) with a mean age of 71.6 years (SD = 10) had lacunar stroke. L-SVD was seen in 142 patients (72.4 %) and L-nonSVD in 54 patients (27.6 %). After 16.4 months, 12 patients had died (6.2%; annual mortality rate 4.4 %), 63 were disabled (32.5 %) and 27 had stroke recurrence (13.9%; annual recurrence rate 9.9 %). Forty-nine patients with L-SVD (34.7 %) and 26 with L-nonSVD (49%) had died or become disabled. Sixteen patients with L-SVD (11.3 %) and 11 with L-nonSVD (20.4 %) had stroke recurrence. On multivariate analysis, L-nonSVD (OR = 2.87, 95% CI 1.08-7.65; p = 0.034) and age (OR = 1.07, 95 % CI 1.02-1.12; p = 0.01) were associated to more severe outcome. L-nonSVD was independently associated with recurrence (OR = 5.03, 95% CI 1.54-16.44; p = 0.006).

CONCLUSIONS

Twenty-seven percent of patients with lacunar stroke have causes other than small vessel disease. These patients have a severe outcome in terms of recurrence,mortality or disability. These findings support the need for a comprehensive diagnostic work-up for patients with lacunar stroke.

Chronic cigarette smoking and the microstructural integrity of white matter in healthy adults: a diffusion tensor imaging study

Results from recent studies suggest that chronic cigarette smoking is associated with increased white matter volume in the brain as determined by in vivo neuroimaging. We used diffusion tensor imaging to examine the microstructural integrity of the white matter in 10 chronic smokers and 10 nonsmokers. All individuals were healthy, without histories of medical or psychiatric illness. Fractional anisotropy (FA) and trace were measured in the genu, body, and splenium of the corpus callosum. FA provides a measure of directional versus nondirectional water diffusion, whereas trace provides a measure of nondirectional water diffusion. Lower FA and higher trace values are considered to reflect less brain integrity. Voxel-based morphometry was used to define volumes in each of these regions of the corpus callosum. Chronic smokers exhibited significantly higher FA in the body and whole corpus callosum and a strong trend for higher FA in the splenium compared with nonsmokers. FA did not differ between groups in the genu, and neither trace nor white matter volumes differed between groups in any of the regions of interest. When subdivided by Fagerström score (low vs. high), the low Fagerström group exhibited significantly higher FA in the body of the corpus callosum compared with the high Fagerström group and the nonsmokers. These results suggest that, among healthy adults, lower exposure to cigarette smoking is associated with increased microstructural integrity of the white matter compared with either no exposure or higher exposure. Additional studies are needed to further explore differences in white matter integrity between smokers and nonsmokers.

Decrease in the Stroke Case Fatality Rates in a French Population-Based Twenty-Year Study

BACKGROUND

The aim of the study was to estimate trends in stroke case fatality in a French population-based study over the last 20 years, and to compare trends in men and women.

METHODS

We prospectively ascertained first-ever strokes in a well-defined population-based study, from 1985 to 2004, in Dijon (France) (150,000 inhabitants). The study was both specific and exhaustive. The follow-up made it possible to analyze case fatality, according to stroke subtypes and sex.

RESULTS

From the ascertainment of 3,691 strokes divided in 1,920 cerebral infarcts from large artery atheroma, 725 cerebral infarcts from small perforating artery atheroma, 497 cardioembolic infarcts, 134 cerebral infarcts from undetermined mechanism, 341 primary cerebral hemorrhages and 74 subarachnoïd hemorrhages, we observed a significant decrease in 28-day case fatality rates of almost 25% (p = 0.03). Case fatality rates decreased in men aged >75 years (p = 0.01) and in women aged >75 years (p = 0.02) and >65 years (p = 0.03). The magnitude of the decrease was smaller in women but not significantly so. According to stroke subtypes, case fatality rates significantly decreased for small perforating artery infarct (p = 0.04) and for primary cerebral hemorrhage (p = 0.03). In multivariate regression analyses, hemorrhagic stroke, the first period of the study (1985-1989), blood hypertension, previous myocardial infarction and age <85 years had a negative effect.

CONCLUSION

This is the first population-based study using continuous ascertainment over a period of 20 years that has demonstrated a significant reduction in case fatality rates. We did not observe any significant differences between men and women.

Seizures and epilepsy in patients with lacunar strokes

BACKGROUND

The relation between seizures and small subcortical infarcts is uncertain. The present retrospective study investigates whether differences are observed between patients with and without seizures following a lacunar stroke.

PATIENTS AND METHODS

Thirty-seven patients with seizures and a prior history of a lacunar stroke were admitted to the Ghent University Hospital during 2000 and 2005. They were compared to 205 patients, admitted between 2002 and 2004, with an acute lacunar stroke and without epileptic spells on follow-up. Nine out of the 37 patients with seizures and 48 out of the 205 without seizures had a history of recurrent strokes.

RESULTS

No differences in vascular risk factors, distribution and frequency of the lacunes, degree of severity of the white matter changes and outcome were observed. On the Mini-Mental State Examination moderate to severe cognitive disturbances were observed in the seizure group and in some patients of the non-seizure group.

CONCLUSIONS

In the present study we found no evidence that seizures are directly induced by lacunar infarcts. The seizures appear to be part of a more global ongoing cerebral disorder probably leading to cognitive impairment.

Incidence, case-fatality rate, and prognosis of ischaemic stroke subtypes in a predominantly Hispanic-Mestizo population in Iquique, Chile (PISCIS project): a community-based incidence study

BACKGROUND

Incidence of ischaemic stroke subtypes, classified by cause, seems to vary between communities. We aimed to prospectively ascertain the incidence of first-ever ischaemic stroke in a predominantly Hispanic-Mestizo population in the northern desertic region of Chile.

METHODS

Between July, 2000, and June, 2002, all patients with possible stroke or transient ischaemic attacks were identified from multiple overlapping sources and were rapidly assessed by two field neurologists. All identified patients were diagnosed by at least two stroke neurologists according to Trial of Org 10172 in Acute Stroke Treatment (TOAST) definitions and were followed up at 6 months. Annual incidence rates were age adjusted to WHO, European, and US populations by the direct method to allow comparisons.

FINDINGS

A total of 239 ischaemic strokes were identified, of which 185 (77%) were first-ever cases. 151 (82%) patients were hospitalised, of whom only 70 (38%) were assessed within 6 h of symptom onset. The mean age of patients was 66.4 years (SD 14.9) and 56% were men. The crude annual incidence rates (per 100 000) according to stroke subtype were: cardioembolic, 9.3; large-artery disease, 2.0; small-vessel disease, 15.8; other determined cause, 0.2; and undetermined cause, 17.4. Hypertension was the most common cardiovascular risk factor in all subtypes and atrial fibrillation was the most common cause of cardioembolic stroke. Case fatality at 30 days was highest in cardioembolic strokes (28%) and lowest in small-vessel disease (0%). Dependency or death at 6 months was also highest in cardioembolic strokes (62%) and lowest in small-vessel disease (21%).

INTERPRETATION

Incidence and prognosis of small vessel and cardioembolic infarction was similar to that in other populations and incidence of large-artery atherothrombotic infarction was lower than in most previous reports. Hypertension and atrial fibrillation were the most common risk factor and cause, respectively, of ischemic stroke in this population. These findings should help the national stroke programme in the prevention of cardioembolic stroke, increase access to specialists and acute brain imaging and vascular studies, and improve stroke care.