Cardiovascular risk factors and TIA characteristics in 19,872 Swedish TIA patients

Transient unilateral weakness: is it a transient ischaemic attack?

Transient ischaemic attack is an emergency medical condition that causes brief negative focal neurological symptoms such as unilateral weakness. The symptoms herald a high risk of stroke and hence require urgent assessment. The challenge lies in the brevity and compendium of associated symptoms that can ‘mimic’ a plethora of other conditions. The result is a high rate of referrals to transient ischaemic attack clinics for these stroke mimics. This article highlights the diagnostic challenges in transient ischaemic attack with relevance to unilateral weakness.

Altered Functional Connectivity and Cognition Persists 4 Years After a Transient Ischemic Attack or Minor Stroke

Background and Purpose: Altered executive functions and resting-state functional connectivity (rsFC) are common following a minor stroke or transient ischemic attack (TIA). However, the long-term persistence of these abnormalities is not well-studied. We investigated whether there were cognitive and rsFC differences between (a) controls and minor cerebrovascular event (CVE) patients and (b) between CVE patients with and without an imaging confirmed infarct (i.e., minor stroke and TIA, respectively) at an average of 3.8 years following their event.

Methods: Structural and resting-state imaging and cognitive assessments including the Montreal Cognitive Assessment, the Trail Making Task and the National Institute of Health (NIH) Cognition Toolbox were conducted on 42 patients (minor stroke = 17, TIA = 25) and 20 healthy controls (total N = 62).

Results: Controls performed better than patients on two measures of executive functioning (both p < 0.046) and had reduced rsFC between the frontoparietal and default mode networks (FPN and DMN, respectively; p = 0.035). No cognitive differences were found between minor stroke and TIA patients, however, rsFC differences were found within the FPN and the DMN (both p < 0.013). Specifically, increased connectivity within the FPN was associated with faster performance in the minor stroke group but not the TIA group (p = 0.047).

Conclusions: These findings suggest that transient or relatively minor cerebrovascular events are associated with persistent disruption of functional connectivity of neural networks and cognitive performance. These findings suggest a need for novel interventions beyond secondary prevention to reduce the risk of persistent cognitive deficits.

Sex Differences in Risk Factors for Transient Ischemic Attack in a Chinese Population

Introduction: This study aimed to collect and evaluate basic information of a stroke screening population in eastern China and to compare distribution differences in risk factors between males and females in a transient ischemic attack (TIA) population. Methods: A standardization of the risk factors for stroke was performed according to an implementation plan of stroke in a high-risk population screening and intervention project in Shandong Province. Of the 231,289 residents, 8,603 patients with a previous TIA were identified and risk factors in this cohort were analyzed for sex differences. Results: In our initial cohort of 231,289 residents, we found 3,390 men and 5,213 women with TIA, accounting for a prevalence of 3.1 and 4.2%, respectively. Risk factors for TIA were hypertension, atrial fibrillation, diabetes, smoking, lack of exercise, overweight, and family history of stroke. In our TIA cohort, we found that the prevalence of smoking was significantly higher in men (41.3%) compared with that found in women (4.2%). Further, hypertension (58.8 vs. 55.5%) and family history of stroke (22.3 vs. 20.0%) were more prevalent in men compared with women, whereas atrial fibrillation (AF) (14.7 vs. 16.4%), diabetes (11.1 vs. 13.2%), lack of exercise (27.2 vs. 28.0%), and overweight (29.5 vs. 35.7%) were less prevalent. Conclusions: In our TIA cohort from eastern China, we found significant sex differences for the risk factors of hypertension, atrial fibrillation, smoking, diabetes, and overweight.

Transient Ischemic Attack and Carotid Web

BACKGROUND AND PURPOSE

Carotid web was recognized as a cause of ischemic stroke. We sought to determine the clinical and imaging profiles of patients with a carotid web as well as its association with TIA.

MATERIALS AND METHODS

A retrospective review of carotid CT angiography studies and brain MR imaging in patients with TIA during the past 3 years (n = 135) was performed to determine the presence of carotid webs by 2 experienced neuroradiologists according to previously published criteria. Demographics and clinical and imaging characteristics are shown by descriptive statistics for patients with an identified carotid web. The agreement in the detection of carotid webs between 2 neuroradiologists was examined using κ statistics.

RESULTS

There were 12 (8.9%) carotid webs at the symptomatic bifurcation and 1 carotid web (0.7%) at the asymptomatic bifurcation, and no hyperintensity was seen on DWI of these 12 patients. Eight of these 12 (75%) patients with a carotid web were women. None of the 12 patients with a carotid web had major risk factors or other causes of TIA. Fair-to-good interobserver agreement (κ = 0.87) was seen for diagnosing a carotid web with CT angiography. The rate (10/12, 83.3%) of short-term recurrent episodes of TIA in patients with TIA with a carotid web was significantly higher than that of patients without a carotid web (15/123, 12.2%) (P < .001).

CONCLUSIONS

The incidence of carotid web in patients with TIA was 8.9%. There is an association between carotid web and patients with TIA without other identified risks. Carotid web may be an underestimated risk factor for TIA.

Non-cardioembolic TIA and ischemic stroke: Implications of severity

OBJECTIVES

Our purpose was to explore major vascular and bleeding outcomes in relation to risk and severity scores (ABCD2 or NIHSS) in patients with transient ischemic attack (TIA) or acute ischemic stroke (AIS).

METHODS

This nationwide observational study was based on data from 4 national registries. Outcomes were assessed by Kaplan-Meier and Cox regression analyses.

RESULTS

The total cohort comprised 21 268 patients (median age 73 years, 47.6% females). Based on ABCD2-score, the TIA-population (n = 10 174) was divided into low-risk (0-3 p, n = 3463) and high-risk (4-7 p, n = 6711). Based on NIHSS-score, the AIS-population (n = 11 454) was divided into minor (0-5 p, n = 8596), moderate (6-10 p, n = 1630) and severe (≥11 p, n = 1228). During follow-up (mean 1.7 years), the composite endpoint of stroke, myocardial infarction or death occurred in 3572 (16.5%) of all the patients, and major bleeding in 668 (3.1%) patients. Using low-risk TIA as reference, the adjusted hazard ratios (HR, 95% CI) of the composite endpoint were 1.41 (1.23-1.62) for high-risk TIA, 1.94 (1.70-2.22) for minor, 2.86 (2.45-3.34) for moderate and 4.18 (3.57-4.90) for severe stroke. When analyzed separately, the association with increased risk remained significant for stroke and death, but not for myocardial infarction. The HR of major bleeding were 1.31 (0.99-1.73) for high-risk TIA, 1.49 (1.13-1.95) for minor, 1.54 (1.08-2.21) for moderate and 2.10 (1.44-3.05) for severe stroke.

CONCLUSIONS

This study confirms the association between severity of the index ischemic stroke and risk of future major vascular and bleeding events, and highlights the increased risk also for patients with high-risk TIA.

Outcome after stroke attributable to baseline factors-The PROSpective Cohort with Incident Stroke (PROSCIS)

Background

The impact of risk factors on poor outcome after ischemic stroke is well known, but estimating the amount of poor outcome attributable to single factors is challenging in presence of multimorbidity. We aim to compare population attributable risk estimates obtained from different statistical approaches regarding their consistency. We use a real-life data set from the PROSCIS study to identify predictors for mortality and functional impairment one year after first-ever ischemic stroke and quantify their contribution to poor outcome using population attributable risks.

Methods

The PROSpective Cohort with Incident Stroke (PROSCIS) is a prospective observational hospital-based cohort study of patients after first-ever stroke conducted independently in Berlin (PROSCIS-B) and Munich (PROSCIS-M). The association of baseline factors with poor outcome one year after stroke in PROSCIS-B was analysed using multiple logistic regression analysis and population attributable risks were calculated, which were estimated using sequential population attributable risk based on a multiple generalized additive regression model, doubly robust estimation, as well as using average sequential population attributable risk. Findings were reproduced in an independent validation sample from PROSCIS-M.

Results

Out of 507 patients with available outcome information after 12 months in PROSCIS-B, 20.5% suffered from poor outcome. Factors associated with poor outcome were age, pre-stroke physical disability, stroke severity (NIHSS), education, and diabetes mellitus. The order of risk factors ranked by magnitudes of population attributable risk was almost similar for all methods, but population attributable risk estimates varied markedly between the methods. In PROSCIS-M, incidence of poor outcome and distribution of baseline parameters were comparable. The multiple logistic regression model could be reproduced for all predictors, except pre-stroke physical disability. Similar to PROSCIS-B, the order of risk factors ranked by magnitudes of population attributable risk was almost similar for all methods, but magnitudes of population attributable risk differed markedly between the methods.

Conclusions

Ranking of risk factors by population impact is not affected by the different statistical approaches. Thus, for a rational decision on which risk factor to target in disease interventions, population attributable risk is a supportive tool. However, population attributable risk estimates are difficult to interpret and are not comparable when they origin from studies applying different methodology. The predictors for poor outcome identified in PROSCIS-B have a relevant impact on mortality and functional impairment one year after first-ever ischemic stroke.