Long-term mortality and recurrent stroke risk among Chinese stroke patients with predominant intracranial atherosclerosis

Gender Differences in Outcomes Among Patients With Symptomatic Intracranial Arterial Stenosis

Background and Purpose— There are limited and conflicting data on gender differences in clinical outcomes among patients with symptomatic intracranial arterial stenosis. This study examined gender differences in patients enrolled in the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) Study.

Methods— Participants were 569 men and women with symptomatic intracranial arterial stenosis. They were followed-up for the occurrence of ischemic stroke and the combined end point of stroke or vascular death from February 1999 through July 2003 (mean follow-up, 1.8 years).

Results— Two-year rates of the primary end point were 28.4% and 16.6% for women and men, respectively. Cumulative probabilities of the outcomes over time were estimated by the Kaplan-Meier product-limit method and were compared between men and women with the use of the log-rank test. Cox proportional hazards regression analyses were used to estimate the hazard ratio of gender (women to men) for ischemic stroke and for the primary end point. The probabilities of ischemic stroke ( P =0.005) and of the combined end point of stroke or vascular death ( P =0.017) over time were significantly higher in women than men. Women had a greater multivariate-adjusted risk for ischemic stroke (HR, 1.85; 95% CI, 1.14 to 3.01; P =0.013) and for the combined end point of stroke or vascular death (HR, 1.58; 95% CI, 1.01 to 2.48; P =0.045).

Conclusions— Women with symptomatic intracranial arterial stenosis are at significantly greater risk for ischemic stroke and for the combined end point of stroke or vascular death. These findings suggest the need for vigorous screening of risk factors and for aggressive management of risk factors and stroke in women. They also suggest the need to ensure adequate numbers of women in clinical trials designed to explore new and promising therapies for intracranial arterial stenosis.

Total cerebral blood flow estimated by color velocity imaging quantification ultrasound: a predictor for recurrent stroke?

Although the Virchow's triad on thrombosis includes reduced blood flow as a factor, there has been relatively little data on the importance of total cerebral blood flow on the risk of subsequent stroke. In the current study, we investigate whether total cerebral blood flow helps predict stroke recurrence. Extracranial arterial blood flow volume estimated by color velocity imaging quantification ultrasound (CVIQ) is an index of cerebral blood flow measurement. We performed a cohort study of 210 consecutive acute stroke patients. Patients were studied with transcranial Doppler and duplex ultrasound for intra- and extracranial large artery disease within 3 days of symptom onset. The association between the risk of recurrent stroke and CVIQ was analyzed with Cox proportional hazards model. Thirty-nine patients (17.7%) developed an ischemic stroke during a mean follow-up of 47.5 months. The mean extracranial blood flow volume was significantly lower for patients who had a recurrent stroke than those without (594.4+/-130.3 versus 683.8+/-176.9 mL/min; P=0.003). In a Cox proportional hazards model adjusting for potential confounding variables, extracranial blood flow volume (hazard ratio (HR) for lowest tertile, 4.1; 95% confidence interval (CI), 1.5 to 11.0) along with male sex (HR, 2.5; 95% CI, 1.3 to 5.1), diabetes (HR, 2.5; 95% CI, 1.2 to 5.0) and large artery stenosis (HR, 2.2; 95% CI, 1.1 to 4.4) were independent predictors for stroke recurrence. Our data indicated that patient with low amount of blood flow to the brain is at risk of recurrent stroke.

Status epilepticus after stroke is associated with increased long-term case fatality

PURPOSE

The aim of this study was to determine the long-term case fatality of patients with a first episode of status epilepticus (SE group) of cerebrovascular etiology, as compared with that in acute stroke patients without SE (AS group).

METHODS

Patients with SE who had been prospectively admitted to an epidemiologic study were retrospectively compared with a cohort of patients from the local stroke registry. The main outcome end point was overall survival. Survival curves were generated according to the Kaplan-Meier method and compared by using the log-rank test. An extended Cox model was used to examine the impact of patient group on the risk of death. Covariates considered potential confounders included age at diagnosis, sex, type of stroke, affected hemisphere, and localization of lesions.

RESULTS

Of 166 patients who entered the study, 93 patients were in the SE group, and 73 patients were in the AS group; 53 SE patients and 35 AS patients died during the study. Patient group (SE vs. AS) showed no significant impact on survival (p=0.0832) in univariate analysis. In contrast, the results from a multivariable analysis suggest that after 6 months, patients with SE were at about twice the risk of death as were patients with AS [hazard ratio of 2.12 with 95% confidence interval, 1.04-4.32, p=0.0392].

CONCLUSIONS

The occurrence of SE in patients with cerebrovascular disease indicates a high risk of death within 3 years. In contrast, the case fatality risk attributable to recurrent status or seizures is lower.

The frequency of symptoms in transient ischaemic attack: analysis of Nanjing Stroke Register Program data

The clinical characteristics of 172 patients experiencing single or multiple (two or more) transient ischaemic attacks (TIAs) were investigated. Risk factors, clinical manifestations and vascular examinations were compared. Intracranial and extra-cranial large-artery disease (stenosis > or = 50%) occurred more frequently in multiple-TIA patients than in single-TIA patients, and weakness and atrial fibrillation were observed more frequently in single TIA than in multiple TIA patients. The type of aetiological examination performed in TIA patients should depend on the frequency of attacks.

Endovaskuläre Behandlung intrakranieller Stenosen

Intracranial stenoses cause 5-10% of all strokes and are increasingly detected by means of modern imaging methods. The stroke danger of high-grade symptomatic stenoses is relatively high, with an annual risk of approximately 10% under medical treatment. Coumadin increases the risk of hemorrhage, and after risk/benefit considerations, antiplatelets should be preferred for antithrombotic therapy. Despite optimized medical treatment, a small group of patients with recurrent symptoms or symptomatic stenoses without adequate collateral supply probably carry higher spontaneous stroke risk and may be considered for intracranial stenting, which itself is associated with procedural risks of up to 10%. Currently published case series show relatively high complication rates as a major drawback of endovascular treatment, mainly strokes after occlusion of perforating branches extending from the stenotic vessel segment or hemorrhagic complications. According to data from smaller feasibility studies, stroke rates in follow-up after successful stenting seem to be low. The average rate of high-grade restenosis with possible indication for reintervention is 10%. Improvements in endovascular treatment aim at reducing vessel wall trauma during balloon angioplasty by underdilatation or the use of self-expanding stents. Until complication rates are dependably reduced to values of 5-6%, indication for endovascular treatment should be restricted to patients without therapeutic alternatives. According to limited data with large variation between different studies, a prospective multicentric registry is proposed for systematic evaluation and further development of the method.

Distribution and Outcome of Symptomatic Stenoses and Occlusions in Patients With Acute Cerebral Ischemia

OBJECTIVE

To describe the distribution of steno-occlusive disease and the associated rate of recurrence in patients with acute cerebral ischemia.

DESIGN

An inception cohort was prospectively recruited after an index event and followed up to assess recurrent stroke and death up to 1 year after the event.

SETTING

Eleven German departments of neurology with acute stroke units.

PATIENTS

A total of 4157 patients who experienced an acute ischemic stroke or a transient ischemic attack and had complete cerebrovascular examination results. Follow-up information could be obtained in 85.3% of these patients.

RESULTS

Symptomatic vessel occlusions were associated with a high mortality rate and were found most often in the proximal internal carotid artery (6.5% of patients), the M1 segment of the middle cerebral artery (3.7%), and the vertebral artery (3.0%). Symptomatic stenosis of 50% to 99% of the internal carotid artery was found in 308 patients (7.4%), and 272 patients (6.5%) had symptomatic intracranial stenosis. The highest rates of recurrent stroke during the first 3 days occurred in patients with symptomatic carotid and intracranial occlusions. Overall, 82 (8.0%) of 1027 patients with symptomatic cerebrovascular disease experienced a recurrent stroke between day 4 and 1 year, but no significant differences in recurrent stroke rates could be found when comparing different locations of steno-occlusive disease.

CONCLUSIONS

Our study provides representative data on the distribution and outcome of steno-occlusive disease in patients with acute cerebral ischemia. In contrast to prior studies in more selected populations, the rate of recurrent stroke in patients with symptomatic intracranial stenosis was not elevated compared with that of patients without steno-occlusive disease.

Aspirin or Anticoagulants in Stenosis of the Middle Cerebral Artery:A Randomized Trial

BACKGROUND

We report the results of an open, randomized, multicenter trial that compared the efficacy of aspirin to oral anticoagulants (OA) for the prevention of vascular events in patients with symptomatic stenosis of the middle cerebral artery (MCA).

METHODS

Participants were randomly assigned to receive 300 mg/day of aspirin or a dose of OA (target INR 2-3). The MCA stenosis was demonstrated by conventional angiography or by at least two noninvasive examinations. Patients had either transient ischemic attack or cerebral infarct (CI) attributable to the MCA stenosis within 90 days before inclusion. The primary endpoint was: nonfatal CI, nonfatal acute myocardial infarct, vascular death and major hemorrhage. The patients were followed-up for a minimum of 1 year and a maximum of 3 years.

RESULTS

The study included 28 patients (14 in each treatment group); the average age was 67 +/- 9.9 years. Men constituted 68% of the patients. After a mean follow-up of 23.1 +/- 10.9 months, there were no recurrences of CI in both groups. No endpoint was reported in the aspirin group, but 2 patients in the OA group (14.3%) exhibited vascular events: 1 acute myocardial infarct and 1 intracerebral hemorrhage). However, this difference was not statistically significant (p = 0.48).

CONCLUSIONS

Our study suggests that aspirin is the treatment of choice for the prevention of vascular events in patients with symptomatic MCA stenosis.

Deep vein thrombosis following ischemic stroke among Asians

BACKGROUND

Deep vein thrombosis (DVT) is perceived as uncommon among Asian stroke patients. However, there is a paucity of published data, and thus, we studied the frequency, characteristics and prognosis of DVT following ischemic stroke in Asian patients with lower limb paresis.

METHODS

Doppler ultrasound scans of the lower limbs were performed at days 7-10 and 25-30 after stroke onset. The functional status of patients was assessed at 6 months using the modified Rankin scale.

RESULTS

DVT was detected in 30% of patients at days 7-10 and in 45% of patients at days 25-30. Most thromboses were distal. There were significant associations of age and degree of weakness with the presence of DVT at days 25-30, but not at days 7-10. DVT in the first month after stroke was associated with poorer outcome at 6 months.

CONCLUSIONS

DVT following ischemic stroke among Asians is common and associated with poor functional outcome.

Prevalence and risk factors of intracranial atherosclerosis in an asymptomatic korean population

Background and Purpose

Intracranial atherosclerosis (ICAS) is one of the major risk factors for ischemic stroke, particularly in Asian populations. We investigated the prevalence and risk factors of ICAS in asymptomatic subjects.

Methods

We prospectively evaluated 835 asymptomatic Korean adults who voluntarily visited a tertiary referral hospital for a health screening examination that included brain magnetic resonance angiography. The subjects had no history of stroke or transient ischemic attacks; those who had potential cardiac sources of emboli were excluded. ICAS and extracranial atherosclerosis were defined as a reduction in luminal diameter of at least 50%. Vascular risk factors were screened through questionnaires, interviews, and examinations.

Results

ICAS was found in 25 subjects (3.0%) and extracranial atherosclerosis was found in 4 patients (0.5%). No patient had combined lesions. ICAS was distributed in 31 arteries in 25 subjects: anterior cerebral arteries (5 subjects, 16%), middle cerebral arteries (16 subjects, 52%), posterior cerebral arteries (8 subjects, 26%), and distal internal carotid arteries (2 subjects, 7%). The ratio of ICAS of the anterior circulation (23 of 31 arteries with ICAS, 74%) to that of the posterior circulation (8 of 31 arteries with ICAS, 26%) was 3:1. The ratio of ICAS (23 of 27 arteries with atherosclerosis in the anterior circulation, 85%) to extracranial atherosclerosis (4 of 27 arteries with therosclerosis in the anterior circulation, 15%) was 6:1. An older age [odds ratio (OR)=1.05, 95% confidence interval (CI)=1.00-1.10] and hypertension (OR=2.41, 95% CI=1.01-5.72) were independent risk factors for ICAS.

Conclusions

ICAS is more prevalent than extracranial atherosclerosis among neurologically asymptomatic Korean adults. Subjects with ICAS are significantly older and have an increased frequency of hypertension compared to those subjects without atherosclerotic stenosis.

Benefits of Modifying the Predictive Factors of Stroke Recurrence

The risk of stroke recurrence is high. With annual rates of around 4%, accumulative rates of 40% are reached within 10 years. Despite being underestimated, the risk is highest in the early stages; around 12% in the first year. The most important etiological subtypes have different levels of risk; the highest being for atherothrombotic infarction and the lowest for lacunar infarction. Each etiology has its own risk factors. For example, in carotid stenosis, the grade of stenosis, ulceration, and plaque morphology, silent infarction on neuroimaging, coexistence of intracranial disease, or microemboli detected on transcranial Doppler, all have predictive value for stroke recurrence. There is a paucity of data on the risk factors for intracranial stenosis. In cardioembolism due to atrial fibrillation age, coexistence of hypertension or diabetes, and echocardiographic data predict recurrence. Risk factors for recurrence do not parallel those for first stroke. Diabetes is the most consistent risk factor for recurrence in different studies, while control of hypertension has been shown to be effective in the prevention of recurrences. Among the inflammatory markers, C-reactive protein is the most effective in prediction of recurrence. Elevated levels of homocysteine also predict recurrence, but attempts to improve risk by the modification of these levels have, to date, been unsuccessful. To be effective, the modification of predictive factors needs to be multifactorial and should be taken into account corresponding to each etiological type. More research is needed on biological markers to establish their clinical relevance and the benefit of targeting them for therapeutic modification.

Basic Mechanisms in Intracranial Large-Artery Atherosclerosis: Advances and Challenges

Intracranial large-artery atherosclerosis is a major cause of ischemic stroke worldwide. Patients affected by this disease are at a high risk of suffering recurrent ischemic events despite antithrombotic therapy. Progression and a greater extent of intracranial atherosclerosis imply a higher risk for recurrence. Studies performed by our group in patients with symptomatic intracranial large-artery atherosclerosis have shown that: (1) C-reactive protein predicts its progression and recurrence, suggesting that inflammation may play a deleterious role in this condition; (2) a high level of the anti-angiogenic endostatin is also associated with a progressive and recurrent intracranial atherosclerosis, which might support a beneficial role for angiogenesis in this group of patients; and (3) elevated lipoprotein(a) concentration and diabetes mellitus characterize those patients with a higher number of intracranial stenoses.

Cilostazol prevents the progression of the symptomatic intracranial arterial stenosis: the multicenter double-blind placebo-controlled trial of cilostazol in symptomatic intracranial arterial stenosis

BACKGROUND AND PURPOSE

Cilostazol, a phosphodiesterase inhibitor, has been reported to reduce restenosis rate after coronary angioplasty and stenting. This study was performed to investigate the effect of cilostazol on the progression of intracranial arterial stenosis (IAS).

METHODS

We randomized 135 patients with acute symptomatic stenosis in the M1 segment of middle cerebral artery or the basilar artery to either cilostazol 200 mg per day or placebo for 6 months. Aspirin 100 mg per day was also given to all patients. Patients with potential embolic sources in the heart or extracranial arteries were excluded. IAS was assessed by magnetic resonance angiogram (MRA) and transcranial Doppler (TCD) at the time of recruitment and 6 months later. The primary outcome was the progression of symptomatic IAS on MRA and secondary outcomes were clinical events and progression on TCD.

RESULTS

Thirty-eight patients were prematurely terminated. Dropout rates and reasons for dropouts were similar between the cilostazol and placebo groups. There was no stroke recurrence in either cilostazol or placebo group, but there was 1 death and 2 coronary events in each group. In cilostazol group, 3 (6.7%) of 45 symptomatic IAS progressed and 11 (24.4%) regressed. In placebo group, 15 (28.8%) of symptomatic IAS progressed and 8 (15.4%) regressed. Progression of symptomatic IAS in cilostazol group was significantly lower than that in placebo group (P=0.008)

CONCLUSIONS

Our study suggests that symptomatic IAS is a dynamic lesion and cilostazol may prevent its progression.

Angiogenesis in symptomatic intracranial atherosclerosis: predominance of the inhibitor endostatin is related to a greater extent and risk of recurrence

BACKGROUND AND PURPOSE

Angiogenesis may be beneficial in chronic myocardial and limb ischemia, but its role in intracranial atherosclerosis remains unknown. We aimed to investigate the relationship between the pro-angiogenic vascular endothelial growth factor (VEGF) and the anti-angiogenic endostatin, and the extent and risk of recurrence of symptomatic intracranial atherosclerosis.

METHODS

Of a total of 94 consecutive patients with symptomatic intracranial stenoses, 40 fulfilled all inclusion criteria. Intracranial stenoses were confirmed by magnetic resonance angiography. Magnetic resonance imaging (MRI) including diffusion-weighted sequences was conducted. Plasmatic VEGF and endostatin were determined from blood samples obtained 3 months after stroke onset, and patients were followed-up thereafter.

RESULTS

A total of 144 intracranial stenoses were confirmed (median number per patient=3). Endostatin/VEGF ratio gradually augmented with the increasing number of intracranial stenoses (r=0.35, P=0.02). Diabetes mellitus (OR, 6.04; CI, 1.1 to 32.2; P=0.03) and a higher endostatin/VEGF ratio (OR, 15.7; CI, 2.2 to 112.3; P=0.006) were independently associated with a greater extent of intracranial atherosclerosis. During a median follow-up of 13 months, 8 patients (20%) experienced a new cerebral ischemic event. A higher baseline endostatin concentration was an independent predictor of new events (hazard ratio, 7.24; CI, 1.6 to 33.8; P=0.011) in a Cox regression model after adjustment for age, sex, number of stenotic vessels, and risk factors. Patients with a higher endostatin level had a lower survival free of new events (P=0.01, log-rank test).

CONCLUSIONS

A predominance of the inhibitor endostatin within the endogenous angiogenic response is associated with a greater extent and risk of recurrence of symptomatic intracranial atherosclerosis, suggesting that angiogenesis may be beneficial in this condition.