Factors affecting the first recurrence of noncardioembolic ischemic stroke

Impacts of treatments on recurrence and 28-year survival of ischemic stroke patients

Aspirin and nicametate are well-established therapies for preventing recurrence and mortality from stroke in patients diagnosed as ischemic stroke. However, their respective effects on the recurrence, making allowance for the duration of recurrence and death without the occurrence of recurrence, and long-term survival have not been well elucidated. We aimed to evaluate long-term effect of two kinds of treatment on cerebrovascular death among ischemic stroke patients with or without the recurrence of stroke. Data used in this study were derived from the cohort based on a multicenter randomized double-blind controlled trial during 1992 to 1995 with the enrollment of a total of 466 patients with first-time non-cardioembolic ischemic stroke who were randomly allocated to receive aspirin (n = 222) or nicametate (n = 244). The trial cohort was followed up over time to ascertain the date of recurrence within trial period and death until Sep of 2019. The time-dependent Cox regression model was used to estimate the long-term effects of two treatments on death from cerebrovascular disease with and without recurrence. A total of 49 patients experienced stroke recurrence and 89 cerebrovascular deaths was confirmed. Patients treated with nicametate were more likely, but non statistically significantly, to have recurrence (aHR: 1.73, 95% CI 0.96–3.13) as compared with those treated by aspirin. Nicametate reduced the risk of cerebrovascular death about 37% (aHR: 0.63, 95% CI 0.41–0.97) compared with aspirin. The aspirin group had a lower recurrence rate than the nicametate group even with recurrence after 1–2 years of follow-up of first stroke but the latter had significantly reduced death from cerebrovascular disease for nicametate group, which requires more research to verify.

Impact of baseline characteristics on outcomes of carotid artery stenting in acute ischemic stroke patients

Carotid artery stenting is an effective treatment for ischemic stroke patients with moderate-to-severe carotid artery stenosis. However, the midterm outcome for patients undergoing this procedure varies considerably with baseline characteristics. To determine the impact of baseline characteristics on outcomes following carotid artery stenting, data from 107 eligible patients with a first episode of ischemic stroke were collected by retrospective chart review. A modified Rankin Scale (mRS) was used to divide patients into two baseline groups, mRS ≤2 and mRS >2. A three-step decision-tree statistical analysis was conducted. After weighting the decision-tree parameters, the following impact hierarchy was obtained: admission low-density lipoprotein, gouty arthritis, chronic kidney disease, ipsilateral common carotid artery resistance index, contralateral ophthalmic artery resistance index, sex, and dyslipidemia. The finite-state machine model demonstrated that, in patients with baseline mRS ≤2, 46% had an improved mRS score at follow-up, whereas 54% had a stable mRS score. In patients with baseline mRS >2, a stable mRS score was observed in 75%, improved score in 23%, and a poorer score in 2%. Admission low-density lipoprotein was the strongest predictive factor influencing poststenting outcome. In addition, our study provides further evidence that carotid artery stenting can be of benefit in first-time ischemic stroke patients with baseline mRS scores >2.

The brainstem is at high risk for recurrent noncardioembolic cerebral infarction in association with diabetes mellitus: a hospital-based study

The goals of the study were to investigate the importance of brainstem infarction (BSI) in recurrent noncardioembolic ischemic stroke and to examine the relevant clinical background. Data were retrospectively reviewed for 655 consecutive patients with acute noncardioembolic infarction who were admitted to our hospital from January 2004 to August 2010. The patients were divided into first-stroke (n = 592) and recurrent-stroke (n = 63) groups. Acute infarcted lesions were explored on MRI, and clinical background factors including age, sex, smoking, atrial fibrillation, coronary heart disease, hypertension, hyperlipidemia and diabetes mellitus (DM) were assessed. The frequency of BSI in the recurrent-stroke group was significantly higher than that in first-stroke patients (30.2 vs. 14.9%, p = 0.0033). No other clinical background factors differed between the two groups. Only the frequency of DM differed significantly among four subgroups formed based on stroke recurrence and BSI (p < 0.0001): DM was present in 63.2% of recurrent-stroke patients with BSI, 54.5% of first-stroke patients with BSI, 27.4% of first-stroke patients without BSI, and 20.5% of recurrent-stroke patients without BSI. We conclude that the brainstem is at high risk for recurrent cerebral infarction in patients with DM.

Reduction of disability after stroke is a more informative predictor of long-time survival than initial disability status

PURPOSE

Few studies have evaluated the roles of reducing disability after stroke in predicting survival. This study aimed to investigate the effects of improvement in the Barthel Index (BI) and other prognostic factors on survival in patients with first-time noncardioembolic ischemic stroke.

METHOD

BI effectiveness was defined as the improvement of BI between initial stroke (within 3 days) and 2 months after stroke. Cox regression analysis and Kaplan-Meier methods were used to evaluate the predictive roles of various prognostic factors.

RESULTS

A total of 111 patients were enrolled. Mean age at the time of stroke was 68 (+ or - 11.2) years. Median follow-up time was 77.4 months. Mean initial BI was 36.1 (+ or - 28.5) and mean BI effectiveness was 46.9 + or - 29.0. Overall, 55 deaths (49.5%) of the cohort were ascertained. The BI effectiveness had significant effects on long-time survival while initial BI was not a significant predictor. Higher BI effectiveness led to lower risk of mortality (hazard ratio = 0.44, 95% CI 0.24 - 0.80, p = 0.007). Elder age was correlated with poor survival (overall p = 0.006). Subjects in the eldest age group (> or = 70 years) showed a significant elevated risk for death (hazard ratio = 3.42, 95% CI 1.18 - 9.92). There was a trend indicating that the smaller the lesion size, the more favourable the prognosis (overall p = 0.057).

CONCLUSIONS

BI effectiveness in the first 2 months after first-time noncardioembolic stroke was more informative than initial disability status for predicting long-time mortality. It highlights the potential benefit in maximizing functional performance in patients with stroke.

Dynamic aspect of functional recovery after stroke using a multistate model

OBJECTIVE

To estimate time to functional recovery and quantify the effects of significant prognostic factors affecting the dynamic change of 3-state functional outcome after stroke.

DESIGN

Modeling of clinical predictions.

SETTING

Referral center.

PARTICIPANTS

One hundred eleven patients with first-time ischemic stroke.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Serial Barthel Index scores at onset, 2 weeks, and 1, 2, 4, and 6 months poststroke. The severity of disability was classified into 3 functional states: poor functional state (PFS) for Barthel Index scores from 0 to 40, moderate functional state (MFS) for scores from 45 to 80, and good functional state (GFS) for scores greater than 80. A 3-state Markov regression model together with Bayesian acyclic graphic underpinning was used to estimate transition parameters and mean time to functional recovery between states and to predict the probability of functional recovery by using Gibbs sampling technique.

RESULTS

The mean total recovery time was 3.1 months for patients with PFS at baseline and 1.3 months for patients with MFS at baseline. The mean recovery times to different functional states were also estimated. Age predominantly affected the probabilities of MFS to GFS transitions, younger patients had faster transition rates (rate ratio, 4.51; 95% confidence interval [CI], 2.72-7.40); but age had only borderline effects on PFS to MFS transitions. In contrast, infarct size exerted substantial effects on PFS to MFS transitions: small-size infarct correlated with a higher transition rate (rate ratio, 10.17; 95% CI, 5.25-20.13), whereas only a borderline effect on MFS to GFS transitions was found. The baseline functional state significantly affected the MFS to GFS transitions.

CONCLUSIONS

By using a multistate model, overall and patient-specific mean time to functional recovery to different functional states can be estimated and the effect of clinical predictors on functional transitions can be precisely quantified to predict patient-specific probability of functional recovery.

Location and size of infarct on functional outcome of noncardioembolic ischemic stroke

PURPOSE

Studies regarding the effects of location and size of infarct on the functional outcome after stroke have yielded inconsistent results. This study aimed to investigate the relationships of neuroimage findings and longitudinal Barthel index (BI) scores in patients with first-ever ischemic stroke.

METHOD

The neuroimage findings of enrolled subjects were grouped by anatomical location. The size of infarct was determined by the largest diameter of the lesion. Patients were followed up prospectively at onset, 2 weeks, 1, 2, 4, and 6 months after stroke. Linear mixed model was employed for the repeated measurement analysis of BI at these six time points in each patient.

RESULTS

A total of 111 patients were enrolled. The BI increased rapidly during the first two months, and reached plateau after four months. The location and size of the lesion had significant effects on serial measurements of BI. After adjustment for age, sex, treatment mode, and baseline BI score, the posterior cerebral artery infarct group showed the largest improvement in BI. There was a trend that the smaller the lesion size, the more favourable the functional outcome.

CONCLUSIONS

Both location and size of lesion in noncardioembolic stroke were significant prognostic factors for functional outcome.

Twenty four hour pulse pressure predicts long term recurrence in acute stroke patients

OBJECTIVES

The impact of different blood pressure (BP) components during the acute stage of stroke on the risk of recurrent stroke is controversial. The present study aimed to investigate by 24 hour BP monitoring a possible association between acute BP values and long term recurrence.

METHODS

A total of 339 consecutive patients with first ever acute stroke underwent 24 hour BP monitoring within 24 hours of ictus. Known stroke risk factors and clinical findings on admission were documented. Patients given antihypertensive medication during BP monitoring were excluded. The outcome of interest during the one year follow up was recurrent stroke. The Cox proportional hazard model was used to analyse association of casual and 24 hour BP recordings with one year recurrence after adjusting for stroke risk factors, baseline clinical characteristics, and secondary prevention therapies.

RESULTS

The cumulative one year recurrence rate was 9.2% (95% CI 5.9% to 12.3%). Multivariate Cox regression analyses revealed age, diabetes mellitus, and 24 hour pulse pressure (PP) as the only significant predictors for stroke recurrence. The relative risk for one year recurrence associated with every 10 mm Hg increase in 24 hour PP was 1.323 (95% CI 1.019 to 1.718, p = 0.036). Higher casual PP levels were significantly related to an increased risk of one year recurrence on univariate analysis, but not in the multivariate Cox regression model.

CONCLUSIONS

Elevated 24 hour PP levels in patients with acute stroke are independently associated with higher risk of long term recurrence. Further research is required to investigate whether the risk of recurrent stroke can be reduced to a greater extent by decreasing the pulsatile component of BP in patients with acute stroke.

Subtyping in ischemic stroke genetic research

Discovery of genes that influence stroke risk might be facilitated if phenotypic heterogeneity of the population studied were reduced by studying individual subtypes of stroke. Standardized systems for classifying stroke are generally mechanistic or syndromic. Mechanistic systems (eg, Trial of ORG10172 in Acute Stroke Treatment) are based on presumed pathophysiologic basis of occlusion. Syndromic systems (eg, Oxfordshire Community Stroke Project) are based on signs and symptoms of neurologic dysfunction. Linkage and candidate gene studies should use such standardized systems in the search for subtype-specific genetic risk factors to increase the validity of interstudy comparisons.