Underlying Causes of TIA and Minor Ischemic Stroke and Risk of Major Vascular Events.

Importance: The coexistence of underlying causes in patients with transient ischemic attack (TIA) or minor ischemic stroke as well as their associated 5-year risks are not well known. Objective: To apply the ASCOD (atherosclerosis, small vessel disease, cardiac pathology, other cause, or dissection) grading system to assess coexistence of underlying causes of TIA and minor ischemic stroke and the 5-year risk for major vascular events. Design, Setting, and Participants: This international registry cohort (TIAregistry.org) study enrolled 4789 patients from June 1, 2009, to December 31, 2011, with 1- to 5-year follow-up at 61 sites in 21 countries. Eligible patients had a TIA or minor stroke (with modified Rankin Scale score of 0 or 1) within the last 7 days. Among these, 3847 patients completed the 5-year follow-up by December 31, 2016. Data were analyzed from October 1, 2022, to June 15, 2023. Exposure: Five-year follow-up. Main Outcomes and Measures: Estimated 5-year risk of the composite outcome of stroke, acute coronary syndrome, or cardiovascular death. Results: A total of 3847 patients (mean [SD] age, 66.4 [13.2] years; 2295 men [59.7%]) in 42 sites were enrolled and participated in the 5-year follow-up cohort (median percentage of 5-year follow-up per center was 92.3% [IQR, 83.4%-97.8%]). In 998 patients with probable or possible causal atherosclerotic disease, 489 (49.0%) had some form of small vessel disease (SVD), including 110 (11.0%) in whom a lacunar stroke was also probably or possibly causal, and 504 (50.5%) had no SVD; 275 (27.6%) had some cardiac findings, including 225 (22.6%) in whom cardiac pathology was also probably or possibly causal, and 702 (70.3%) had no cardiac findings. Compared with patients with none of the 5 ASCOD categories of disease (n = 484), the 5-year rate of major vascular events was almost 5 times higher (hazard ratio [HR], 4.86 [95% CI, 3.07-7.72]; P < .001) in patients with causal atherosclerosis, 2.5 times higher (HR, 2.57 [95% CI, 1.58-4.20]; P < .001) in patients with causal lacunar stroke or lacunar syndrome, and 4 times higher (HR, 4.01 [95% CI, 2.50-6.44]; P < .001) in patients with causal cardiac pathology. Conclusion and Relevance: The findings of this cohort study suggest that in patients with TIA and minor ischemic stroke, the coexistence of atherosclerosis, SVD, cardiac pathology, dissection, or other causes is substantial, and the 5-year risk of a major vascular event varies considerably across the 5 categories of underlying diseases. These findings further suggest the need for secondary prevention strategies based on pathophysiology rather than a one-size-fits-all approach.

Effect of atherosclerosis on 5-year risk of major vascular events in patients with transient ischaemic attack or minor ischaemic stroke: an international prospective cohort study.

BACKGROUND: The prevalence of atherosclerosis and the long-term risk of major vascular events in people who have had a transient ischaemic attack or minor ischaemic stroke, regardless of the causal relationship between the index event and atherosclerosis, are not well known. In this analysis, we applied the ASCOD (atherosclerosis, small vessel disease, cardiac pathology, other causes, and dissection) grading system to estimate the 5-year risk of major vascular events according to whether there was a causal relationship between atherosclerosis and the index event (ASCOD grade A1 and A2), no causal relationship (A3), and with or without a causal relationship (A1, A2, and A3). We also aimed to estimate the prevalence of different grades of atherosclerosis and identify associated risk factors. METHODS: We analysed patient data from TIAregistry.org, which is an international, prospective, observational registry of patients with a recent (within the previous 7 days) transient ischaemic attack or minor ischaemic stroke (modified Rankin Scale score of 0-1) from 61 specialised centres in 21 countries in Europe, Asia, the Middle East, and Latin America. Using data from case report forms, we applied the ASCOD grading system to categorise the degree of atherosclerosis in our population (A0: no atherosclerosis; A1 or A2: atherosclerosis with stenosis ipsilateral to the cerebral ischaemic area; A3: atherosclerosis in vascular beds not related to the ischaemic area or ipsilateral plaques without stenosis; and A9: atherosclerosis not assessed). The primary outcome was a composite of non-fatal stroke, non-fatal acute coronary syndrome, or cardiovascular death within 5 years. FINDINGS: Between June 1, 2009, and Dec 29, 2011, 4789 patients were enrolled to TIAregistry.org, of whom 3847 people from 42 centres participated in the 5-year follow-up; 3383 (87·9%) patients had a 5-year follow-up visit (median 92·3% [IQR 83·4-97·8] per centre). 1406 (36·5%) of 3847 patients had no atherosclerosis (ASCOD grade A0), 998 (25·9%) had causal atherosclerosis (grade A1 or A2), and 1108 (28·8%) had atherosclerosis that was unlikely to be causal (grade A3); in 335 (8·7%) patients, atherosclerosis was not assessed (grade A9). The 5-year event rate of the primary composite outcome was 7·7% (95% CI 6·3-9·2; 101 events) in patients categorised with grade A0 atherosclerosis, 19·8% (17·4-22·4; 189 events) in those with grade A1 or A2, and 13·8% (11·8-16·0; 144 events) in patients with grade A3. Compared with patients with grade A0 atherosclerosis, patients categorised as grade A1 or A2 had an increased risk of the primary composite outcome (hazard ratio 2·77, 95% CI 2·18-3·53; p<0·0001), as did patients with grade A3 (1·87, 1·45-2·42; p<0·0001). Except for age, male sex, and multiple infarctions on neuroimaging, most of the risk factors that were identified as being associated with grade A1 or A2 atherosclerosis were modifiable risk factors (ie, hypertension, dyslipidaemia, overweight, smoking cigarettes, and low physical activity; all p values <0·025). INTERPRETATION: In patients with transient ischaemic attack or minor ischaemic stroke, those with atherosclerosis have a much higher risk of major vascular events within 5 years than do those without atherosclerosis. Preventive strategies addressing complications of atherosclerosis should focus on individuals with atherosclerosis rather than grouping together all people who have had a transient ischaemic attack or minor ischaemic stroke (including those without atherosclerosis). FUNDING: AstraZeneca, Sanofi, Bristol Myers Squibb, SOS Attaque Cérébrale Association.

Risk of subsequent disabling or fatal stroke in patients with transient ischaemic attack or minor ischaemic stroke: an international, prospective cohort study.

BACKGROUND: Patients who have had a transient ischaemic attack or minor stroke have an increased risk of cardiovascular events for the following 5 years. We aimed to assess 5-year functional outcomes in patients with transient ischaemic attack or minor ischaemic stroke and to determine the factors associated with long-term disability. METHODS: We analysed data from patients in TIAregistry.org, an international, prospective, observational registry of patients with transient ischaemic attack or minor ischaemic stroke from 61 specialised centres in 21 countries. Patients aged 18 years or older who had a transient ischaemic attack or minor stroke within the previous 7 days between May 30, 2009, and Dec 30, 2011, with a baseline modified Rankin scale (mRS) score of 0-1, and who had been followed up for 5 years, were eligible for inclusion in this study. We evaluated whether existing comorbidities and stroke recurrence, categorised as disabling (mRS score of >1, including death) or non-disabling (mRS score of 0-1), at 5 years after baseline, were associated with poor functional outcome (defined as an mRS score of >1). We used multivariable generalised equation models for factors associated with poor functional outcome at 5 years and multivariable cause-specific Cox hazard regression models in case of stroke recurrence. FINDINGS: Between May 30, 2009, and Dec 30, 2011, 3847 eligible patients were included in the study, 3105 (80·7%) of whom had an mRS evaluation at 5 years of follow-up. Median follow-up duration was 5·00 years (IQR 4·78-5·00). 710 (22·9%) of 3105 patients had an mRS score greater than 1 at 5 years. Factors associated with poor functional outcome at 5 years were older age (per 10-year increase, odds ratio [OR] 2·18, 95% CI 1·93-2·46; p<0·0001), diabetes of any type (1·45, 1·18-1·78; p=0·0001), history of stroke or transient ischaemic attack before the qualifying event (1·74, 1·37-2·22; p<0·0001), hypertension (1·38, 1·00-1·92; p=0·050), atrial fibrillation or flutter (1·52, 1·04-1·94; p=0·030), congestive heart failure (1·73, 1·22-2·46; p=0·0024), valvular disease (2·47, 1·70-3·58; p<0·0001), stroke as qualifying event (1·31, 1·09-1·57; p=0·0037), history of peripheral artery disease (1·98, 1·28-3·07; p=0·0023), history of coronary artery disease (1·32, 1·00-1·74; p=0·049), intracranial haemorrhage during follow up (4·94, 1·91-12·78; p=0·0013), and living alone (1·32, 1·10-1·59; p=0·0031). Regular physical activity before the index event was associated with reduced risk of poor functional outcome (OR 0·52, 95% CI 0·42-0·66; p<0·0001). 345 recurrent strokes had occurred at 5 years of follow-up, 141 (40·9%) of which were disabling or fatal. Stroke recurrence increased the risk of having a disability at 5 years (OR 3·52, 95% CI 2·37-5·22; p<0·0001). Recurrent disabling or fatal strokes were independently associated with older age (per 10-year increase, hazard ratio [HR] 1·61, 95% CI 1·35-1·92; p<0·0001), diabetes of any type (2·23, 1·56-3·17; p<0·0001), National Institutes of Health Stroke Scale score of greater than 5 at discharge (5·11, 2·15-12·13; p=0·0013), history of coronary artery disease (1·76, 1·17-2·65; p=0·0063), history of stroke or transient ischaemic attack before the qualifying event (1·54, 1·03-2·29; p=0·035), congestive heart failure (1·86, 1·01-3·47; p=0·044), stroke as qualifying event (1·73, 1·22-2·45; p=0·0024), mRS score of greater than 1 at discharge (2·48, 1·27-4·87; p=0·0083), and intracranial haemorrhage during follow-up (17·15, 9·95-27·43; p<0·0001). Regular physical activity before the index event was associated with reduced risk of recurrent disabling stroke at 5 years (HR 0·56, 95% CI 0·31-0·99; p=0·046), and 5-year disability without recurrent stroke (0·61, 0·47-0·79; p=0·0001). INTERPRETATION: We found a substantial burden of disability (mRS score of >1) at 5 years after transient ischaemic attack or minor ischemic stroke, and most predictors of this disability were modifiable risk factors. Patients who did regular physical exercise before the index event had a significantly reduced risk of disability at 5 years compared with patients who did no exercise. FUNDING: AstraZeneca, Sanofi, Bristol Myers Squibb, SOS Attaque Cérébrale Association.

MICROSCOPE Mission: Final Results of the Test of the Equivalence Principle.

The MICROSCOPE mission was designed to test the weak equivalence principle (WEP), stating the equality between the inertial and the gravitational masses, with a precision of 10^{-15} in terms of the Eötvös ratio η. Its experimental test consisted of comparing the accelerations undergone by two collocated test masses of different compositions as they orbited the Earth, by measuring the electrostatic forces required to keep them in equilibrium. This was done with ultrasensitive differential electrostatic accelerometers onboard a drag-free satellite. The mission lasted two and a half years, cumulating five months worth of science free-fall data, two-thirds with a pair of test masses of different compositions-titanium and platinum alloys-and the last third with a reference pair of test masses of the same composition-platinum. We summarize the data analysis, with an emphasis on the characterization of the systematic uncertainties due to thermal instabilities and on the correction of short-lived events which could mimic a WEP violation signal. We found no violation of the WEP, with the Eötvös parameter of the titanium and platinum pair constrained to η(Ti,Pt)=[-1.5±2.3(stat)±1.5(syst)]×10^{-15} at 1σ in statistical errors.

Five-Year Prognosis After TIA or Minor Ischemic Stroke in Asian and Non-Asian Populations.

OBJECTIVE: To determine long-term vascular outcomes of Asian patients who experienced TIA or minor ischemic stroke and to compare the outcomes of Asian patients with those of non-Asian patients, in the context of modern guideline-based prevention strategies. METHODS: This is a subanalysis of the TIAregistry.org project, in which 3,847 patients (882 from Asian and 2,965 from non-Asian countries) with a recent TIA or minor ischemic stroke were assessed and treated by specialists at 42 dedicated units from 14 countries and followed for 5 years. The primary outcome was a composite of cardiovascular death, nonfatal stroke, and nonfatal acute coronary syndrome. RESULTS: No differences were observed in the 5-year risk of the primary outcome (14.0% vs 11.7%; hazard ratio [HR], 1.10; 95% confidence interval [CI], 0.88-1.37; p = 0.41) and stroke (10.7% vs 8.5%; HR, 1.17; 95% CI, 0.90-1.51; p = 0.24) between Asian and non-Asian patients. Asian participants were at higher risk of intracranial hemorrhage (1.8% vs 0.8%; HR, 2.23; 95% CI, 1.09-4.57; p = 0.029). Multivariable analysis showed that the presence of multiple acute infarctions on initial brain imaging was an independent predictor of primary outcome and modified Rankin Scale score of >1 in both Asian (HR, 1.91; 95% CI, 1.11-3.29; p = 0.020) and non-Asian (HR, 1.39; 95% CI, 1.02-1.90; p = 0.037) patients. CONCLUSION: The long-term risk of vascular events in Asian patients was as low as that in non-Asian patients, while Asian participants had a 2.2-fold higher intracranial hemorrhage risk. Multiple acute infarctions were independently associated with future disability in both groups. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that among people who experienced TIA or minor stroke, Asian patients have a similar 5-year risk of cardiovascular death, stroke, and acute coronary syndrome as non-Asian patients.

Carotid Atherosclerosis Evolution When Targeting a Low-Density Lipoprotein Cholesterol Concentration <70 mg/dL After an Ischemic Stroke of Atherosclerotic Origin.

BACKGROUND: The TST trial (Treat Stroke to Target) showed the benefit of targeting a low-density lipoprotein cholesterol (LDL-C) concentration of <70 mg/dL in terms of reducing the risk of major cardiovascular events in 2860 patients with ischemic stroke with atherosclerotic stenosis of cerebral vasculature. The impact on carotid atherosclerosis evolution is not known. METHODS: TST-PLUS (Treat Stroke to Target-Plaque Ultrasound Study) included 201 patients assigned to an LDL-C concentration of <70 mg/dL and 212 patients assigned to a target of 100±10 mg/dL. To achieve these goals, investigators used the statin and dosage of their choice and added ezetimibe as needed. Ultrasonographers were certified and carotid ultrasound examinations were performed using M'Ath software at baseline and at 2, 3, and 5 years. All images were uploaded to the Intelligence in Medical Technologies database directly from the carotid ultrasound device. The central core laboratory performed all offline measurements of the intima-media thickness of both common carotid arteries blinded from the randomization arm. The main outcomes were newly diagnosed atherosclerotic plaque on carotid bifurcation or internal carotid artery using the Mannheim consensus definition and between-group comparison of common carotid arteries intima-media thickness change. RESULTS: After a median follow-up of 3.1 years, the achieved LDL-C concentrations were 64 mg/dL (1.64 mmol/L) in the lower-target group and 106 mg/dL (2.72 mmol/L) in the higher-target group. Compared with the higher-target group, patients in the lower-target group had a similar incidence of newly diagnosed carotid plaque: 46/201 (5-year rate, 26.1%) versus 45/212 (5-year rate, 29.7%). The change in common carotid arteries intima-media thickness was -2.69 µm (95% CI, -6.55 to 1.18) in the higher-target group and -10.53 µm (95% CI, -14.21 to -6.85) in the lower-target group, resulting in an absolute between-group difference of -7.84 µm (95% CI, -13.18 to -2.51; P=0.004). CONCLUSIONS: In patients with ischemic stroke and atherosclerosis, an LDL-C target of <70 mg/dL (1.8 mmol/L) did not reduce the incidence of new carotid plaques but produced significantly greater regression of carotid atherosclerosis than an LDL-C target of 90 to 110 mg/dL. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01252875.

A Comparison of Two LDL Cholesterol Targets after Ischemic Stroke.

BACKGROUND: The use of intensive lipid-lowering therapy by means of statin medications is recommended after transient ischemic attack (TIA) and ischemic stroke of atherosclerotic origin. The target level for low-density lipoprotein (LDL) cholesterol to reduce cardiovascular events after stroke has not been well studied. METHODS: In this parallel-group trial conducted in France and South Korea, we randomly assigned patients with ischemic stroke in the previous 3 months or a TIA within the previous 15 days to a target LDL cholesterol level of less than 70 mg per deciliter (1.8 mmol per liter) (lower-target group) or to a target range of 90 mg to 110 mg per deciliter (2.3 to 2.8 mmol per liter) (higher-target group). All the patients had evidence of cerebrovascular or coronary-artery atherosclerosis and received a statin, ezetimibe, or both. The composite primary end point of major cardiovascular events included ischemic stroke, myocardial infarction, new symptoms leading to urgent coronary or carotid revascularization, or death from cardiovascular causes. RESULTS: A total of 2860 patients were enrolled and followed for a median of 3.5 years; 1430 were assigned to each LDL cholesterol target group. The mean LDL cholesterol level at baseline was 135 mg per deciliter (3.5 mmol per liter), and the mean achieved LDL cholesterol level was 65 mg per deciliter (1.7 mmol per liter) in the lower-target group and 96 mg per deciliter (2.5 mmol per liter) in the higher-target group. The trial was stopped for administrative reasons after 277 of an anticipated 385 end-point events had occurred. The composite primary end point occurred in 121 patients (8.5%) in the lower-target group and in 156 (10.9%) in the higher-target group (adjusted hazard ratio, 0.78; 95% confidence interval, 0.61 to 0.98; P = 0.04). The incidence of intracranial hemorrhage and newly diagnosed diabetes did not differ significantly between the two groups. CONCLUSIONS: After an ischemic stroke or TIA with evidence of atherosclerosis, patients who had a target LDL cholesterol level of less than 70 mg per deciliter had a lower risk of subsequent cardiovascular events than those who had a target range of 90 mg to 110 mg per deciliter. (Funded by the French Ministry of Health and others; Treat Stroke to Target ClinicalTrials.gov number, NCT01252875.).

New Test of Lorentz Invariance Using the MICROSCOPE Space Mission.

We use data from the T-SAGE instrument on board the MICROSCOPE space mission to search for Lorentz violation in matter-gravity couplings as described by the Lorentz violating standard model extension (SME) coefficients (a[over ¯]_{eff})_{µ}^{w}, where (µ=T, X, Y, Z) and (w=e, p, n) for the electron, proton, and neutron. One of the phenomenological consequences of a nonzero value of those coefficients is that test bodies of different composition fall differently in an external gravitational field. This is similar to "standard" tests of the universality of free fall, but with a specific signature that depends on the orbital velocity and rotation of Earth. We analyze data from five measurement sessions of MICROSCOPE spread over a year finding no evidence for such a signature, but setting constraints on linear combinations of the SME coefficients that improve on best previous results by 1 to 2 orders of magnitude. Additionally, our independent linear combinations are different from previous ones, which increases the diversity of available constraints, paving the way towards a full decorrelation of the individual coefficients.

Treat stroke to target trial design: First trial comparing two LDL targets in patients with atherothrombotic strokes.

BACKGROUND: In patients with non-cardio-embolic stroke, atorvastatin 80 mg/day reduced the relative risk of recurrent stroke by 16%, and a post hoc analysis showed that achieving an LDL-c of less than 70 mg/dL reduced the relative risk by 28% as compared to an on-treatment LDL of 100 mg/dL or more. Current guidelines from the French drug agency recommend treating with a statin after an ischaemic stroke to a target of less than 100 mg/dL, but no study directly tested LDL-c targets. The Treat Stroke to Target (TST) trial will compare the efficacy of achieving an LDL-c of less than 70 mg/dL versus an achieved LDL-c of 100 ± 10 mg/dL for secondary prevention in patients with recent ischaemic stroke of atherosclerotic origin.Main hypothesis: An achieved on-treatment LDL-c of less than 70 mg/dL will reduce by 25% the risk of recurrent ischaemic stroke, myocardial infarction, urgent coronary or carotid revascularisation following new symptoms requiring hospitalisation, and vascular death compared with on-treatment LDL-c of 100 ± 10 mg/dL. DESIGN: Patients are randomised to either LDL-c levels, and the investigator who is not blinded can use the lipid-lowering agent of his/her choice available on the market (including statins and ezetimibe), in order to achieve the assigned LDL-c level. To be eligible for enrolment, patients have a recent ischaemic stroke or TIA of atherosclerotic origin with at least one arterial stenosis of a cerebral artery, enrolled between acute phase of the qualifying stroke (once the neurological deficit is stabilised) and three months. The initial planned sample size of 3760 participants followed three years was amended to allow follow-up of all enrolled patients until 385 primary efficacy outcome events have occurred, and no later than 31 December 2019. Patients will be recruited in 76 sites in two countries (France and South Korea) between March 2010 and December 2018 (last included patient followed up to one year). Safety outcomes will include haemorrhagic strokes and new onset diabetes. All primary endpoints will be adjudicated by an endpoint committee, blinded to the assigned LDL-c level. Two sub-studies assess (1) the relative effect of assigned LDL-c levels on occurrence of new atherosclerotic plaque as detected by carotid ultrasound during follow-up, using M'ATH software for repositioning and (2) the genetic and biomarker drivers of recurrent primary endpoints according to assigned LDL-c lowering arm, in atherosclerotic strokes. SUMMARY: The TST trial is evaluating the benefits of achieving an LDL-c less than 70 mg/dL for secondary stroke prevention in ischaemic stroke patients of atherosclerotic origin. Main results are anticipated in 2020 or earlier (ClinicalTrials.gov NCT01252875).

Five-Year Risk of Stroke after TIA or Minor Ischemic Stroke.

BACKGROUND: After a transient ischemic attack (TIA) or minor stroke, the long-term risk of stroke and other vascular events is not well known. In this follow-up to a report on 1-year outcomes from a registry of TIA clinics in 21 countries that enrolled 4789 patients with a TIA or minor ischemic stroke from 2009 through 2011, we examined the 5-year risk of stroke and vascular events. METHODS: We evaluated patients who had had a TIA or minor stroke within 7 days before enrollment in the registry. Among 61 sites that participated in the 1-year outcome study, we selected 42 sites that had follow-up data on more than 50% of their enrolled patients at 5 years. The primary outcome was a composite of stroke, acute coronary syndrome, or death from cardiovascular causes (whichever occurred first), with an emphasis on events that occurred in the second through fifth years. In calculating the cumulative incidence of the primary outcome and secondary outcomes (except death from any cause), we treated death as a competing risk. RESULTS: A total of 3847 patients were included in the 5-year follow-up study; the median percentage of patients with 5-year follow-up data per center was 92.3% (interquartile range, 83.4 to 97.8). The composite primary outcome occurred in 469 patients (estimated cumulative rate, 12.9%; 95% confidence interval [CI], 11.8 to 14.1), with 235 events (50.1%) occurring in the second through fifth years. At 5 years, strokes had occurred in 345 patients (estimated cumulative rate, 9.5%; 95% CI, 8.5 to 10.5), with 149 of these patients (43.2%) having had a stroke during the second through fifth years. Rates of death from any cause, death from cardiovascular causes, intracranial hemorrhage, and major bleeding were 10.6%, 2.7%, 1.1%, and 1.5%, respectively, at 5 years. In multivariable analyses, ipsilateral large-artery atherosclerosis, cardioembolism, and a baseline ABCD2 score for the risk of stroke (range, 0 to 7, with higher scores indicating greater risk) of 4 or more were each associated with an increased risk of subsequent stroke. CONCLUSIONS: In a follow-up to a 1-year study involving patients who had a TIA or minor stroke, the rate of cardiovascular events including stroke in a selected cohort was 6.4% in the first year and 6.4% in the second through fifth years. (Funded by AstraZeneca and others.).

MICROSCOPE Mission: First Constraints on the Violation of the Weak Equivalence Principle by a Light Scalar Dilaton.

The existence of a light or massive scalar field with a coupling to matter weaker than gravitational strength is a possible source of violation of the weak equivalence principle. We use the first results on the Eötvös parameter by the MICROSCOPE experiment to set new constraints on such scalar fields. For a massive scalar field of mass smaller than 10^{-12} eV (i.e., range larger than a few 10^{5} m), we improve existing constraints by one order of magnitude to |α|<10^{-11} if the scalar field couples to the baryon number and to |α|<10^{-12} if the scalar field couples to the difference between the baryon and the lepton numbers. We also consider a model describing the coupling of a generic dilaton to the standard matter fields with five parameters, for a light field: We find that, for masses smaller than 10^{-12} eV, the constraints on the dilaton coupling parameters are improved by one order of magnitude compared to previous equivalence principle tests.

Prevalence of Systemic Atherosclerosis Burdens and Overlapping Stroke Etiologies and Their Associations With Long-term Vascular Prognosis in Stroke With Intracranial Atherosclerotic Disease.

Importance: Patients who have experienced stroke with intracranial atherosclerotic disease (ICAD) may also have concomitant atherosclerosis in different arterial beds and other possible causes for ischemic stroke. However, little is known about the frequency and prognostic effect of such overlapping diseases. Objectives: To describe the prevalence of systemic atherosclerotic burdens and overlapping stroke etiologies and their contributions to long-term prognoses among patients who have experienced stroke with ICAD. Design, Setting, and Participants: The Asymptomatic Myocardial Ischemia in Stroke and Atherosclerotic Disease study is a single-center prospective study in which 405 patients with acute ischemic stroke within 10 days of onset were consecutively enrolled between June 2005 and December 2008 and followed up for 4 years. After excluding 2 patients because of incomplete investigations, 403 were included in this analysis. Main Outcomes and Measures: Significant ICAD was defined as having 50% or greater stenosis/occlusion by contrast-enhanced/time-of-flight magnetic resonance angiography, computed tomography angiography, and/or transcranial Doppler ultrasonography. Systemic vascular investigations on atherosclerotic disease were performed with ultrasonography in carotid arteries, aorta and femoral arteries, and by angiography in coronary arteries. Coexistent stroke etiologies were assessed using the atherosclerosis, small-vessel disease, cardiac pathology, other cause, and dissection (ASCOD) grading system. We estimated the 4-year risk of major adverse cardiovascular events (MACE), including vascular death, nonfatal cardiac events, nonfatal stroke, and major peripheral arterial events. Results: Of 403 participants, 298 (74%) were men and the mean (SD) age was 62.6 (13.1) years. Significant ICAD was found in 146 (36.2%). Patients with significant ICAD more often had aortic arch (70 [60.9%] vs 99 [49.0%]; P = .04) and coronary artery (103 [76.9%] vs 153 [63.2%]; P = .007) atherosclerosis than those without. Among patients with ICAD, concurrent stenosis in the extracranial carotid artery (24 [23.4%] vs 3 [9.0%]; P = .08; adjusted hazard ratio[aHR] = 2.12) and the coronary artery (19 [29.9%] vs 8 [12.8%]; P = .01; aHR = 1.90) increased the MACE risk. Furthermore, patients with ICAD who also had any cardiac pathology (ASCOD grade C1-3) were at a higher MACE risk than others (grade C0) (20 [28.2%] vs 7 [11.4%]; P = .01; aHR = 2.24). By contrast, patients with ICAD with any form of small vessel disease (grade S1-3) had a lower MACE risk than those without (grade S0) (20 [17.3%] vs 6 [34.6%]; P = .05; aHR = 0.23). Conclusions and Relevance: Patients with ICAD often have coexisting systemic atherosclerosis and multiple potential stroke mechanisms that affect their prognosis, suggesting that extensive evaluations of overlapping diseases may allow better risk stratification.

MICROSCOPE Mission: First Results of a Space Test of the Equivalence Principle.

According to the weak equivalence principle, all bodies should fall at the same rate in a gravitational field. The MICROSCOPE satellite, launched in April 2016, aims to test its validity at the 10^{-15} precision level, by measuring the force required to maintain two test masses (of titanium and platinum alloys) exactly in the same orbit. A nonvanishing result would correspond to a violation of the equivalence principle, or to the discovery of a new long-range force. Analysis of the first data gives δ(Ti,Pt)=[-1±9(stat)±9(syst)]×10^{-15} (1σ statistical uncertainty) for the titanium-platinum Eötvös parameter characterizing the relative difference in their free-fall accelerations.

Differences in Characteristics and Outcomes Between Asian and Non-Asian Patients in the TIAregistry.org.

BACKGROUND AND PURPOSE: This study provides the contemporary causes and prognosis of transient ischemic attack (TIA) and minor stroke in Asians and the direct comparisons with non-Asians. METHODS: The TIAregistry.org enrolled 4789 patients (1149 Asians and 3640 non-Asians) with a TIA or minor ischemic stroke within 7 days of onset. Every participating facility had systems dedicated to urgent intervention of TIA/stroke patients by specialists. The primary outcome was a composite of cardiovascular death, nonfatal stroke, and nonfatal acute coronary syndrome. RESULTS: Approximately 80% of patients were evaluated within 24 hours of symptom onset. At 1 year, there were no differences in the rates of composite cardiovascular events (6.8% versus 6.0%; P=0.38) and stroke (6.0% versus 4.8%; P=0.11) between Asians and non-Asians. Asians had a lower risk of cerebrovascular disease (stroke or TIA) than non-Asians (adjusted hazard ratio, 0.79; 95% confidence interval, 0.63-0.98; P=0.03); the difference was primarily driven by a lower rate of TIA in Asians (4.2% versus 8.3%; P<0.001). Moderately severe bleeding was more frequent in Asians (0.8% versus 0.3%; P=0.02). In multivariable analysis, multiple acute infarcts (P=0.005) and alcohol consumption (P=0.02) were independent predictors of stroke recurrence in Asians, whereas intracranial stenosis (P<0.001), ABCD2 score (P<0.001), atrial fibrillation (P=0.008), extracranial stenosis (P=0.03), and previous stroke or TIA (P=0.03) were independent predictors in non-Asians. CONCLUSIONS: The short-term stroke risk after a TIA or minor stroke was lower than expected when urgent evidence-based care was delivered, irrespective of race/ethnicity or region. However, the predictors of stroke were different for Asians and non-Asians.

Clinical Significance of Isolated Atypical Transient Symptoms in a Cohort With Transient Ischemic Attack.

BACKGROUND AND PURPOSE: Contrary to typical transient symptoms (TS), atypical TS, such as partial sensory deficit, dysarthria, vertigo/unsteadiness, unusual cortical visual deficit, and diplopia, are not usually classified as symptoms of transient ischemic attack when they occur in isolation, and their clinical relevance is frequently denied. METHODS: Consecutive patients with recent TS admitted in our transient ischemic attack clinic (2003-2008) had systematic brain, arterial, and cardiac investigations. We compared the prevalence of recent infarction on brain imaging, major investigational findings (symptomatic intracranial or extracranial atherosclerotic stenosis ≥50%, cervical arterial dissection, and major source of cardiac embolism), and 1-year risk of major vascular events in patients with isolated typical or atypical TS and nonisolated TS, after exclusion of the main differential diagnoses. RESULTS: Among 1850 patients with possible or definite ischemic diagnoses, 798 (43.1%) had isolated TS: 621 (33.6%) typical and 177 (9.6%) atypical. Acute infarction on brain imaging was similar in patients with isolated atypical and typical TS but less frequent than in patients with nonisolated TS, observed in 10.0%, 11.5%, and 15.3%, respectively (P<0.0001). Major investigational findings were found in 18.1%, 26.4%, and 26.3%, respectively (P=0.06). One-year risk of a major vascular events was not significantly different in the 3 groups. CONCLUSIONS: Transient ischemic attack diagnosis should be considered and investigated in patients with isolated atypical TS.

Symptomatic Patients Remain at Substantial Risk of Arterial Disease Complications Before and After Endarterectomy or Stenting.

BACKGROUND AND PURPOSE: After carotid endarterectomy (CEA) or carotid artery stenting (CAS) in patients with transient ischemic attack or minor ischemic stroke, recurrent stroke risk falls to a low rate on modern medical treatment. METHODS: We used data from 4583 patients with recent transient ischemic attack or minor stroke enrolled in the TIAregistry.org to perform a nested case-control analysis to evaluate pre- and post-CEA/CAS risk. Cases were defined as patients with a CEA/CAS during the 1-year follow-up period. For each case, 2 controls with a follow-up time greater than the time from qualifying event to CEA/CAS were randomly selected, matched by age and sex. Primary outcome was defined as major vascular events (MVE, including stroke, cardiovascular death, and myocardial infarction). RESULTS: The median delay from symptom onset of qualifying event to CEA/CAS was 11 days (interquartile range, 6-23). Overall, patients with CEA/CAS had a higher 1-year risk of MVE than other patients (14.8% versus 5.8%; adjusted hazard ratio, 2.40; 95% confidence interval, 1.61-3.60; P<0.001). During the matched preprocedural period, MVE occurred in 14 (7.5%) cases and in 13 (3.5%) controls, with an adjusted odds ratio =2.46 (95% confidence interval, 1.07-5.64; P=0.03). In the postprocedural period, the risk of MVE was also higher in cases than in controls (adjusted P<0.03). CONCLUSIONS: Patients with CEA/CAS had a higher 12-month risk of MVE, as well as during pre- and postprocedural periods. These results suggest that patients in whom CEA/CAS is anticipated are likely to be an informative population for inclusion in studies testing new antithrombotic strategies started soon after symptom onset.

One-Year Risk of Stroke after Transient Ischemic Attack or Minor Stroke.

BACKGROUND: Previous studies conducted between 1997 and 2003 estimated that the risk of stroke or an acute coronary syndrome was 12 to 20% during the first 3 months after a transient ischemic attack (TIA) or minor stroke. The TIAregistry.org project was designed to describe the contemporary profile, etiologic factors, and outcomes in patients with a TIA or minor ischemic stroke who receive care in health systems that now offer urgent evaluation by stroke specialists. METHODS: We recruited patients who had had a TIA or minor stroke within the previous 7 days. Sites were selected if they had systems dedicated to urgent evaluation of patients with TIA. We estimated the 1-year risk of stroke and of the composite outcome of stroke, an acute coronary syndrome, or death from cardiovascular causes. We also examined the association of the ABCD(2) score for the risk of stroke (range, 0 [lowest risk] to 7 [highest risk]), findings on brain imaging, and cause of TIA or minor stroke with the risk of recurrent stroke over a period of 1 year. RESULTS: From 2009 through 2011, we enrolled 4789 patients at 61 sites in 21 countries. A total of 78.4% of the patients were evaluated by stroke specialists within 24 hours after symptom onset. A total of 33.4% of the patients had an acute brain infarction, 23.2% had at least one extracranial or intracranial stenosis of 50% or more, and 10.4% had atrial fibrillation. The Kaplan-Meier estimate of the 1-year event rate of the composite cardiovascular outcome was 6.2% (95% confidence interval, 5.5 to 7.0). Kaplan-Meier estimates of the stroke rate at days 2, 7, 30, 90, and 365 were 1.5%, 2.1%, 2.8%, 3.7%, and 5.1%, respectively. In multivariable analyses, multiple infarctions on brain imaging, large-artery atherosclerosis, and an ABCD(2) score of 6 or 7 were each associated with more than a doubling of the risk of stroke. CONCLUSIONS: We observed a lower risk of cardiovascular events after TIA than previously reported. The ABCD(2) score, findings on brain imaging, and status with respect to large-artery atherosclerosis helped stratify the risk of recurrent stroke within 1 year after a TIA or minor stroke. (Funded by Sanofi and Bristol-Myers Squibb.).

Intima-media thickness of carotid arteries.

Carotid intima-media thickness (CIMT) is a validated predictive marker of increased plaque occurrence and the incidence of major cardiovascular events. However, due to technical issues associated with the measurement of CIMT, a well-trained and certified sonographer is needed to overcome causes of variability due to the patient, device, sonographer, and quantification tool. The recently updated Mannheim consensus defined and described how to differentiate CIMT from plaques. These definitions allow for the better analysis and quantification of early atherosclerosis. Indications for CIMT measurements largely include the detection of coronary heart disease risk among intermediate-risk patients. CIMT is frequently used in clinical trials, and recent technical recommendations have been provided to improve the quality of the procedures. The final choice of a CIMT protocol depends on the purpose of the measurement, the research question at hand, the cost effectiveness, the quality of the data and the added value provided by the additional information.

Thromboxane prostaglandin receptor antagonist and carotid atherosclerosis progression in patients with cerebrovascular disease of ischemic origin: a randomized controlled trial.

BACKGROUND AND PURPOSE: Thromboxane prostaglandin receptors have been implicated to be involved in the atherosclerotic process. We assessed whether Terutroban, a thromboxane prostaglandin receptor antagonist, affects the progression of atherosclerosis, as measured by common carotid intima-media thickness and carotid plaques. METHODS: A substudy was performed among 1141 participants of the aspirin-controlled Prevention of Cerebrovascular and Cardiovascular Events of Ischemic Origin with Terutroban in Patients with a History of Ischemic Stroke or Transient Ischemic Attack (PERFORM) trial. Common carotid intima-media thickness and carotid plaque occurrence was measured during a 3-year period. RESULTS: Baseline characteristics did not differ between Terutroban (n=592) and aspirin (n=549) treated patients and were similar as in the main study. Mean study and treatment duration were similar (28 and 25 months, respectively). In the Terutroban group, the annualized rate of change in common carotid intima-media thickness was 0.006 mm per year (95% confidence interval, -0.004 to 0.016) and -0.005 mm per year (95% confidence interval, -0.015 to 0.005) in the aspirin group. There was no statistically significant difference between the groups in the annualized rate of change of common carotid intima-media thickness (0.011 mm per year; 95% confidence interval, -0.003 to 0.025). At 12 months of follow-up, 66% of Terutroban patients had no emergent plaques, 31% had 1 to 2 emergent plaques, and 3% had ≥3 emergent plaques. In the aspirin group, the corresponding percentages were 64%, 32%, and 4%. Over time, there was no statistically significant difference in the number of emergent carotid plaques between treatment modalities (rate ratio, 0.91; 95% confidence interval, 0.77-1.07). CONCLUSIONS: Compared with aspirin, Terutroban did not beneficially affect progression of carotid atherosclerosis among well-treated patients with a history of ischemic stroke or transient ischemic attacks with an internal carotid stenosis <70%. CLINICAL TRIAL REGISTRATION URL: http://www.controlled-trials.com. Unique identifier: ISRCTN66157730.