Beta-Amyloid Related Neurodegenerative and Neurovascular Diseases: Potential Implications for Transfusion Medicine.

Cerebral amyloid angiopathy (CAA) is a progressive cerebrovascular and neurodegenerative disorder that is caused by the aberrant accumulation of soluble beta-amyloid isoforms in the small vessel walls of the cerebral and cerebellar cortices and the leptomeninges. Vascular beta-amyloid deposition increases vulnerability to intracerebral hemorrhage (ICH). Clinically, CAA can be the underlying cause of up to half of spontaneous lobar ICHs and can also present with convexity subarachnoid hemorrhage, transient focal neurologic episodes and progressive cognitive decline leading to dementia. The majority of CAA is sporadic, with increasing prevalence with age and often coexists with Alzheimer's Disease (AD). Genetic and iatrogenic etiologies are rare. Cases of CAA and AD have been linked to the use of cadaveric pituitary hormone and later life iatrogenic CAA has also been described following early-life neurosurgical procedures with cadaveric dura grafts. Together these data suggest a capacity of beta-amyloid transmissibility. A recent study found that in over 1 million transfusion recipients from donors who later developed (i) >1 ICH or (ii) one ICH event and dementia, had an elevated risk of developing future ICH. Considering prior reports of transfusion associated variant-Creutzfeldt Jakob Disease in humans and in vivo evidence in sheep, coupled with emerging data supporting beta-amyloid's prion-like properties, raises the question of whether CAA could be transmissible by blood transfusion. This would also have implications for screening, especially in an era of emerging plasma biomarkers of cerebral amyloidosis. Given the public health concerns raised by this biologically plausible question, there is a need for future studies with well-characterized definitions - and temporal ascertainment - of CAA exposure and outcomes to examine whether CAA is transfusion-transmissible, and, if so, with what frequency and timing of onset.

Advance Consent for participation in Acute Stroke Trials (ACTION): protocol for a feasibility study.

INTRODUCTION: Obtaining informed consent for research from patients in medical emergencies remains a challenge, particularly in acute stroke care as treatment must be administered quickly and patients often arrive in the hospital in a state of incapacitation. Adaptations to standard consenting approaches-such as the use of surrogate consent or deferral of consent-have significant limitations. This feasibility study aims to test a new consenting approach in acute stroke care that we call advance consent. Advance consent has the potential to render emergency trial enrolment faster, fairer and more transparent, leading to more generalisable results. METHODS AND DESIGN: We will conduct a five-part study at The Ottawa Hospital, a quaternary care stroke centre: (1) administering questionnaires in the Ottawa Hospital Stroke Prevention Clinic that will examine patients' perspectives on research participation and advance consent; (2) inviting participants to consent in advance to any or both currently enrolling acute stroke trials; (3) tracking patient enrolment into these trials over 1 year; (4) administering a follow up questionnaire to participants at 1 year and (5) administering a questionnaire to participating hospital staff in order to interrogate their experiences with advance consent. Outcomes include but are not limited to eligibility rate, recruitment rate, withdrawal rate and the proportion of patients whose advance consent results in trial enrolment. CONCLUSION: This study will test the feasibility of enrolling patients at risk of stroke into acute stroke trials using advance consent.

Effect of thrombolysis type on the efficacy of aspiration versus stent retriever first line thrombectomy: results from the AcT trial.

BACKGROUND: Intravenous (IV) tenecteplase is increasingly being used in lieu of alteplase for acute ischemic stroke. We sought to study the influence of IV tenecteplase versus IV alteplase on the efficacy of first line thrombectomy strategy. METHODS: This was a secondary analysis of the Alteplase versus Tenecteplase (AcT) trial. We included anterior and posterior circulation stroke patients in whom a thrombectomy was attempted. We compared outcomes for stent retriever as first line strategy versus contact aspiration alone, and interactions with thrombolysis type. We examined angiographic outcomes (extended final thrombolysis in cerebral infarction (eTICI) 2c-3 after first-pass, eTICI 2b-3 and eTICI 2 c-3 on final angiography), and clinical and safety outcomes. Mixed effect regression analyses with interaction terms were performed. All outcomes were assessed and analyzed by blinded adjudicators. RESULTS: Among 506 patients who received thrombectomy, 435 were included (222 (51.0%) IV tenecteplase, 213 (49.0%) IV alteplase). A stent retriever was used as the first line endovascular thrombectomy (EVT) approach in 288 (66.2%), and aspiration in 147 (33.8%) patients. There was no difference in rates of final eTICI 2c-3 between groups (57.0% with stent retriever vs 61.9% with aspiration; P=0.35). There was, however, a significant interaction (P=0.02) between thrombolysis type and first line EVT strategy for final eTICI 2c-3, where tenecteplase was associated with higher odds of final eTICI 2c-3 with aspiration (adjusted OR (aOR) 2.29, 95% CI 1.10 to 4.75), but not with stent retriever (aOR 0.63, 95% CI 0.38 to 1.04). No significant interaction between thrombolysis and first line strategy was found for the other angiographic, clinical or safety outcomes. CONCLUSION: IV tenecteplase before EVT may enhance reperfusion with first line aspiration. TRIAL REGISTRATION NUMBER: NCT03889249.

Intravenous alteplase versus tenecteplase in patients with acute posterior circulation strokes: A secondary analysis from the AcT randomized controlled trial.

OBJECTIVES: There are limited data available demonstrating the safety and efficacy of intravenous tenecteplase versus alteplase in patients with acute ischemic stroke in the posterior circulation. MATERIALS AND METHODS: This is a post-hoc analysis of the Alteplase compared to Tenecteplase (AcT) pragmatic, phase 3, registry-linked randomized controlled trial. Patients with any posterior circulation vessel occlusion on baseline imaging were included. Study outcomes included 90-day modified Rankin Scale (mRS) 0-1, mRS 0-2, ordinal mRS, death within 90 days, 24 h symptomatic intracerebral haemorrhage (sICH) and successful reperfusion/recanalization. Mixed effects regression adjusting for age, sex and stroke severity was used to analyze differences in outcomes between patients administered tenecteplase vs. alteplase. Further, sensitivity analysis was conducted for basilar artery occlusion (BAO) alone. RESULTS: Of 1577 patients, 136 (8.6 %, 77:alteplase, 59:tenecteplase) had posterior circulation stroke. Baseline characteristics were similar[median age 71 (IQR 60-81) vs. 72 (IQR 65-82) years, 57.1 % vs. 67.8 % males, median baseline NIHSS 7 (IQR 4-12) vs. 7 (IQR 4-16) in alteplase vs. tenecteplase arms, respectively]. 28 patients (20.6 %, 16:alteplase, 12:tenecteplase arm) underwent EVT. The median 90-120 days mRS was 2 (IQR 1-4). There were no differences between alteplase and tenecteplase for 90-d mRS 0-1 (adjRR 0.93;95 %CI 0.63-1.36), 90-day mRS 0-2 (adjRR 0.95; 95 %CI 0.72-1.26), sICH (RR 0.65; 95 %CI 0.06-7.02) and mortality (RR 1.21; 95 %CI 0.61-2.38). Successful reperfusion eTICI 2b-3 and successful recanalization rAOL 2b-3 was achieved in 23/28 (82 %, 12:alteplase, 11:tenecteplase) and in 16/28 (57 %, 14:alteplase, 12:tenecteplase), respectively. Similar results were seen in 31 patients (22.8 %) with BAO. CONCLUSION: Intravenous tenecteplase has a similar effect on outcome as alteplase, without increased safety concerns in patients with acute posterior circulation strokes.

The treatment effect across ASPECTS in acute ischemic stroke: Analysis from the AcT trial.

BACKGROUND: Early ischemic changes on baseline imaging are commonly evaluated for acute stroke decision-making and prognostication. AIMS: We assess the association of early ischemic changes on clinical outcomes and whether it differs between intravenous tenecteplase and Alteplase. METHODS: Data are from the phase 3, Alteplase compared to Tenecteplase (AcT) trial. Subjects with anterior circulation stroke were included. Early ischemic changes were assessed using the Alberta Stroke Program Early CT score (ASPECTS). Efficacy outcomes included modified Rankin scale (mRS) 0-1, mRS 0-2, and ordinal mRS at 90 days. Safety outcomes included 24-h symptomatic intracerebral hemorrhage (sICH), any hemorrhage on follow-up scan, and 90-day mortality rate. Mixed-effects logistic regression was used to assess the association of ASPECTS (continuous and categorical (0-4 vs 5-7 vs 8-10)) with outcomes and if these associations were modified by thrombolytic type after adjusting for age, sex, and baseline stroke severity. RESULTS: Of the 1577 patients in the trial, 901 patients (56.3%; median age 75 years (IQR 65-84), 50.8% females, median National Institute of Health Stroke Scale (NIHSS) 14 (IQR 17-19)) with anterior circulation stroke were included. mRS 0-1 at 90 days was achieved in 1/14 (0.3%), 43/160 (14.7%), and 252/726 (85.1%) in the ASPECTS 0-4, 5-7, and 8-10 groups respectively. Every one-point decrease in ASPECTS was associated with 2.7% and 1.9% decrease in chances of mRS 0-1 and mRS 0-2 at 90 days, respectively, and 1.9% chances of increase in mortality at 90 days. Subgroup analysis in endovascular thrombectomy (EVT)-treated population showed similar results. Thrombolytic type did not modify this association between ASPECTS and 90-day mRS 0-1 (P-interaction 0.75). There was no significant interaction by thrombolytic type with any other outcomes. CONCLUSION: Similar to prior studies, we found that every one-point decrease in ASPECTS was associated with poorer clinical and safety outcomes. This effect did not differ between alteplase and tenecteplase. DATA ACCESS STATEMENT: Data shall made available on reasonable request from the PI (BMM).

Perivascular spaces, plasma GFAP, and speeded executive function in neurodegenerative diseases.

INTRODUCTION: We investigated the effect of perivascular spaces (PVS) volume on speeded executive function (sEF), as mediated by white matter hyperintensities (WMH) volume and plasma glial fibrillary acidic protein (GFAP) in neurodegenerative diseases. METHODS: A mediation analysis was performed to assess the relationship between neuroimaging markers and plasma biomarkers on sEF in 333 participants clinically diagnosed with Alzheimer's disease/mild cognitive impairment, frontotemporal dementia, or cerebrovascular disease from the Ontario Neurodegenerative Disease Research Initiative. RESULTS: PVS was significantly associated with sEF (c = -0.125 ± 0.054, 95% bootstrap confidence interval [CI] [-0.2309, -0.0189], p = 0.021). This effect was mediated by both GFAP and WMH. DISCUSSION: In this unique clinical cohort of neurodegenerative diseases, we demonstrated that the effect of PVS on sEF was mediated by the presence of elevated plasma GFAP and white matter disease. These findings highlight the potential utility of imaging and plasma biomarkers in the current landscape of therapeutics targeting dementia. HIGHLIGHTS: Perivascular spaces (PVS) and white matter hyperintensities (WMH) are imaging markers of small vessel disease. Plasma glial fibrillary protein acidic protein (GFAP) is a biomarker of astroglial injury. PVS, WMH, and GFAP are relevant in executive dysfunction from neurodegeneration. PVS's effect on executive function was mediated by GFAP and white matter disease.

Clinical Predictors of Acute Ischemia in Patients with Low-Risk Neurological Deficits.

BACKGROUND: Diagnosis of acute ischemia typically relies on evidence of ischemic lesions on magnetic resonance imaging (MRI), a limited diagnostic resource. We aimed to determine associations of clinical variables and acute infarcts on MRI in patients with suspected low-risk transient ischemic attack (TIA) and minor stroke and to assess their predictive ability. METHODS: We conducted a post-hoc analysis of the Diagnosis of Uncertain-Origin Benign Transient Neurological Symptoms (DOUBT) study, a prospective, multicenter cohort study investigating the frequency of acute infarcts in patients with low-risk neurological symptoms. Primary outcome parameter was defined as diffusion-weighted imaging (DWI)-positive lesions on MRI. Logistic regression analysis was performed to evaluate associations of clinical characteristics with MRI-DWI-positivity. Model performance was evaluated by Harrel's c-statistic. RESULTS: In 1028 patients, age (Odds Ratio (OR) 1.03, 95% Confidence Interval (CI) 1.01-1.05), motor (OR 2.18, 95%CI 1.27-3.65) or speech symptoms (OR 2.53, 95%CI 1.28-4.80), and no previous identical event (OR 1.75, 95%CI 1.07-2.99) were positively associated with MRI-DWI-positivity. Female sex (OR 0.47, 95%CI 0.32-0.68), dizziness and gait instability (OR 0.34, 95%CI 0.14-0.69), normal exam (OR 0.55, 95%CI 0.35-0.85) and resolved symptoms (OR 0.49, 95%CI 0.30-0.78) were negatively associated. Symptom duration and any additional symptoms/symptom combinations were not associated. Predictive ability of the model was moderate (c-statistic 0.72, 95%CI 0.69-0.77). CONCLUSION: Detailed clinical information is helpful in assessing the risk of ischemia in patients with low-risk neurological events, but a predictive model had only moderate discriminative ability. Patients with clinically suspected low-risk TIA or minor stroke require MRI to confirm the diagnosis of cerebral ischemia.

Vascular calcification in chronic kidney disease associated with pathogenic variants in ABCC6.

Vascular calcification is prevalent in chronic kidney disease (CKD). Genetic causes of CKD account for 10-20% of adult-onset disease. Vascular calcification is thought to be one of the most important risk factors for increased cardiovascular morbidity and mortality in CKD patients and is detectable in 80% of patients with end stage kidney disease (ESKD). Despite the high prevalence of vascular calcification in CKD, no single gene cause has been described. We hypothesized that variants in vascular calcification genes may contribute to disease pathogenesis in CKD, particularly in families who exhibit a predominant vascular calcification phenotype. We developed a list of eight genes that are hypothesized to play a role in vascular calcification due to their involvement in the ectopic calcification pathway: ABCC6, ALPL, ANK1, ENPP1, NT5E, SLC29A1, SLC20A2, and S100A12. With this, we assessed exome data from 77 CKD patients, who remained unsolved following evaluation for all known monogenic causes of CKD. We also analyzed an independent cohort (Ontario Neurodegenerative Disease Research Initiative (ONDRI), n = 520) who were screened for variants in ABCC6 and compared this to a control cohort of healthy adults (n = 52). We identified two CKD families with heterozygous pathogenic variants (R1141X and A667fs) in ABCC6. We identified 10 participants from the ONDRI cohort with heterozygous pathogenic or likely pathogenic variant in ABCC6. Replication in a healthy control cohort did not reveal any variants. Our study provides preliminary data supporting the hypothesis that ABCC6 may play a role in vascular calcification in CKD. By screening CKD patients for genetic causes early in the diagnostic pathway, patients with genetic causes associated with vascular calcification can potentially be preventatively treated with new therapeutics with aims to decrease mortality.

Combining Early Ischemic Change and Collateral Extent for Functional Outcomes After Endovascular Therapy: An Analysis From AcT Trial.

BACKGROUND: Early ischemic change and collateral extent are colinear with ischemic core volume (ICV). We investigated the relationship between a combined score using the Alberta Stroke Program Early Computed Tomography Score and multiphase computed tomography angiography (mCTA) collateral extent, named mCTA-ACE score, on functional outcomes in endovascular therapy-treated patients. METHODS: We performed a post hoc analysis of a subset of endovascular therapy-treated patients from the Alteplase Compared to Tenecteplase trial which was conducted between December 2019 and January 2022 at 22 centers across Canada. Ten-point mCTA collateral corresponding to M2 to M6 regions of the Alberta Stroke Program Early Computed Tomography Score grid was evaluated as 0 (poor), 1 (moderate), or 2 (normal) and additively combined with the 10-point Alberta Stroke Program Early Computed Tomography Score to produce a 20-point mCTA-ACE score. We investigated the association of mCTA-ACE score with modified Rankin Scale score ≤2 and return to prestroke level of function at 90 to 120 days using mixed-effects logistic regression. In the subset of patients who underwent baseline computed tomography perfusion imaging, we compared the mCTA-ACE score and ICV for outcome prediction. RESULTS: Among 1577 intention-to-treat population in the trial, 368 (23%; 179 men; median age, 73 years) were included, with Alberta Stroke Program Early Computed Tomography Score, mCTA collateral, and combination of both (mCTA-ACE score: median [interquartile range], 8 [7-10], 9 [8-10], and 17 [16-19], respectively). The probability of modified Rankin Scale score ≤2 and return to prestroke level of function increased for each 1-point increase in mCTA-ACE score (odds ratio, 1.16 [95% CI, 1.06-1.28] and 1.22 [95% CI, 1.06-1.40], respectively). Among 173 patients in whom computed tomography perfusion data was assessable, the mCTA-ACE score was inversely correlated with ICV (ρ=-0.46; P<0.01). The mCTA-ACE score was comparable to ICV to predict a modified Rankin Scale score ≤2 and return to prestroke level of function (C statistics 0.71 versus 0.69 and 0.68 versus 0.64, respectively). CONCLUSIONS: The mCTA-ACE score had a significant positive association with functional outcomes after endovascular therapy and had a similar predictive performance as ICV.

Effect of Endovascular Thrombectomy for Acute Ischemic Stroke on Cognitive Outcomes: A Secondary Analysis of the ESCAPE Trial.

BACKGROUND AND OBJECTIVES: The effect of endovascular therapy (EVT) for large vessel occlusion stroke on cognitive outcomes is not well understood. We evaluated the effect of EVT on cognitive function in the Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times (ESCAPE) trial. METHODS: Patient data from the ESCAPE randomized trial were analyzed. Cognitive assessments completed at 90 days after stroke were the Montreal Cognitive Assessment (MoCA), the Sunnybrook Neglect Assessment Procedure (SNAP), the Boston Naming Test (BNT), Trail-making test A (Trails A), and Trail-making test B (Trails B). We used logistic regression to evaluate the association between EVT and favorable cognitive outcome on the 5 separate tests, adjusting for demographic and clinical factors. We used generalized estimating equations and ordinal regression to determine the odds of favorable outcome with EVT on global cognition incorporating the 5 tests. We added final infarct volume (FIV) to the models to assess the relationship of FIV with cognitive outcome. RESULTS: The ESCAPE trial included 315 patients, 165 randomized to EVT and 150 randomized to control. There was higher odds of favorable outcome with EVT for MoCA (adjusted odds ratio [aOR] 2.32, 95% CI 1.30-4.16), SNAP (aOR 3.85, 95% CI 2.00-7.45), BNT (aOR 2.33, 95% CI 1.30-4.17), trails A (aOR 3.50, 95% CI 1.93-6.36), and trails B (aOR 2.56, 95% CI 1.46-4.48). There was higher odds of favorable outcome with EVT on global binary (aOR 2.57, 95% CI 1.67-3.94) and ordinal analyses (aOR 2.83, 95% CI 1.68-4.76) of cognitive function. After adding FIV to the models, both FIV and EVT were significantly associated with cognitive outcome. There was a significant correlation between global cognitive performance and mRS at day 90 (r = -0.78, p < 0.001), with the largest reductions in favorable cognitive outcome from mRS score 4 to 5 and from mRS 2 to 3. DISCUSSION: In this secondary analysis of the ESCAPE trial, EVT was associated with favorable outcome on 5 separate cognitive tests and in global analyses of cognitive benefit. These results provide novel evidence for the effect of EVT on cognition and support the global benefit of treatment with EVT. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with acute ischemic stroke due to intracranial internal carotid artery (ICA) or M1 segment MCA occlusion, including tandem extracranial ICA occlusions, EVT compared with best medical therapy increased odds of favorable cognitive outcome.

Link among apolipoprotein E E4, gait, and cognition in neurodegenerative diseases: ONDRI study.

INTRODUCTION: Apolipoprotein E E4 allele (APOE E4) and slow gait are independently associated with cognitive impairment and dementia. However, it is unknown whether their coexistence is associated with poorer cognitive performance and its underlying mechanism in neurodegenerative diseases. METHODS: Gait speed, APOE E4, cognition, and neuroimaging were assessed in 480 older adults with neurodegeneration. Participants were grouped by APOE E4 presence and slow gait. Mediation analyses were conducted to determine if brain structures could explain the link between these factors and cognitive performance. RESULTS: APOE E4 carriers with slow gait had the lowest global cognitive performance and smaller gray matter volumes compared to non-APOE E4 carriers with normal gait. Coexistence of APOE E4 and slow gait best predicted global and domain-specific poorer cognitive performances, mediated by smaller gray matter volume. DISCUSSION: Gait slowness in APOE E4 carriers with neurodegenerative diseases may indicate extensive gray matter changes associated with poor cognition. HIGHLIGHTS: APOE E4 and slow gait are risk factors for cognitive decline in neurodegenerative diseases. Slow gait and smaller gray matter volumes are associated, independently of APOE E4. Worse cognition in APOE E4 carriers with slow gait is explained by smaller GM volume. Gait slowness in APOE E4 carriers indicates poorer cognition-related brain changes.

Neuropsychiatric symptoms and brain morphology in patients with mild cognitive impairment, cerebrovascular disease and Parkinson disease: A cross sectional and longitudinal study.

OBJECTIVES: Neuropsychiatric symptoms (NPS) increase risk of developing dementia and are linked to various neurodegenerative conditions, including mild cognitive impairment (MCI due to Alzheimer's disease [AD]), cerebrovascular disease (CVD), and Parkinson's disease (PD). We explored the structural neural correlates of NPS cross-sectionally and longitudinally across various neurodegenerative diagnoses. METHODS: The study included individuals with MCI due to AD, (n = 74), CVD (n = 143), and PD (n = 137) at baseline, and at 2-years follow-up (MCI due to AD, n = 37, CVD n = 103, and PD n = 84). We assessed the severity of NPS using the Neuropsychiatric Inventory Questionnaire. For brain structure we included cortical thickness and subcortical volume of predefined regions of interest associated with corticolimbic and frontal-executive circuits. RESULTS: Cross-sectional analysis revealed significant negative correlations between appetite with both circuits in the MCI and CVD groups, while apathy was associated with these circuits in both the MCI and PD groups. Longitudinally, changes in apathy scores in the MCI group were negatively linked to the changes of the frontal-executive circuit. In the CVD group, changes in agitation and nighttime behavior were negatively associated with the corticolimbic and frontal-executive circuits, respectively. In the PD group, changes in disinhibition and apathy were positively associated with the corticolimbic and frontal-executive circuits, respectively. CONCLUSIONS: The observed correlations suggest that underlying pathological changes in the brain may contribute to alterations in neural activity associated with MBI. Notably, the difference between cross-sectional and longitudinal results indicates the necessity of conducting longitudinal studies for reproducible findings and drawing robust inferences.

Infarct Evolution on MR-DWI After Thrombectomy in Acute Stroke Patients Randomized to Nerinetide or Placebo: The REPERFUSE-NA1 Study

BACKGROUND AND OBJECTIVES: The neuroprotectant nerinetide has shown promise in reducing infarct volumes in primate models of ischemia reperfusion. We hypothesized that early secondary infarct growth after endovascular therapy (EVT) (1) may be a suitable surrogate biomarker for testing neuroprotective compounds, (2) is feasible to assess in the acute setting using sequential MRI, and (3) can be modified by treatment with nerinetide. METHODS: REPERFUSE-NA1 was a prospective, multisite MRI substudy of the randomized controlled trial ESCAPE-NA1 (ClinicalTrials.gov NCT02930018) that involved patients with acute disabling large vessel occlusive stroke undergoing EVT within 12 hours of onset who were randomized to receive intravenous nerinetide or placebo. Patients enrolled in REPERFUSE-NA1 underwent sequential MRI <5 hours post-EVT (day 1) and at 24 hours (day 2). The primary outcome was total diffusion-weighted MRI infarct growth early after EVT, defined as the lesion volume difference between day 2 and day 1. The secondary outcome was region-specific infarct growth in different brain tissue compartments. Statistical analyses were performed using the Mann-Whitney U test and multiple linear regression. RESULTS: Sixty-seven of 71 patients included had MRI of sufficient quality. The median infarct volume post-EVT was 12.98 mL (IQR, 5.93-28.08) in the nerinetide group and 10.80 mL (IQR, 3.11-24.45) in the control group (p = 0.59). Patients receiving nerinetide showed a median early secondary infarct growth of 5.92 mL (IQR, 1.09-21.30) compared with 10.80 mL (interquartile range [IQR], 2.54-21.81) in patients with placebo (p = 0.30). Intravenous alteplase modified the effect of nerinetide on region-specific infarct growth in white matter and basal ganglia compartments. In patients with no alteplase, the infarct growth rate was reduced by 120% (standard error [SE], 60%) in the white matter (p = 0.03) and by 340% (SE, 140%) in the basal ganglia (p = 0.02) in the nerinetide group compared with placebo after adjusting for confounders. DISCUSSION: This study highlights the potential of using MR imaging as a biomarker to estimate the effect of a neuroprotective agent in acute stroke treatment. Patients with acute large vessel occlusive stroke exhibited appreciable early infarct growth both in the gray matter and the white matter after undergoing EVT. Acknowledging relatively small overall infarct volumes in this study, treatment with nerinetide was associated with slightly reduced percentage infarct growth in the white matter and basal ganglia compared with placebo in patients not receiving intravenous alteplase and had no effect on the total early secondary infarct growth. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov NCT02930018. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with acute large vessel ischemic stroke undergoing EVT, nerinetide did not significantly decrease early post-EVT infarct growth compared with placebo.

Intravenous tenecteplase compared with alteplase for minor ischaemic stroke: a secondary analysis of the AcT randomised clinical trial.

BACKGROUND: In ischaemic stroke, minor deficits (National Institutes of Health Stroke Scale (NIHSS) ≤5) at presentation are common but often progress, leaving patients with significant disability. We compared the efficacy and safety of intravenous thrombolysis with tenecteplase versus alteplase in patients who had a minor stroke enrolled in the Alteplase Compared to Tenecteplase in Patients With Acute Ischemic Stroke (AcT) trial. METHODS: The AcT trial included individuals with ischaemic stroke, aged >18 years, who were eligible for standard-of-care intravenous thrombolysis. Participants were randomly assigned 1:1 to intravenous tenecteplase (0.25 mg/kg) or alteplase (0.9 mg/kg). Patients with minor deficits pre-thrombolysis were included in this post-hoc exploratory analysis. The primary efficacy outcome was the proportion of patients with a modified Rankin Score (mRS) of 0-1 at 90-120 days. Safety outcomes included mortality and symptomatic intracranial haemorrhage (sICH). RESULTS: Of the 378 patients enrolled in AcT with an NIHSS of ≤5, the median age was 71 years, 39.7% were women; 194 (51.3%) received tenecteplase and 184 (48.7%) alteplase. The primary outcome (mRS score 0-1) occurred in 100 participants (51.8%) in the tenecteplase group and 86 (47.5 %) in the alteplase group (adjusted risk ratio (RR) 1.14 (95% CI 0.92 to 1.40)). There were no significant differences in the rates of sICH (2.9% in tenecteplase vs 3.3% in alteplase group, unadjusted RR 0.79 (0.24 to 2.54)) and death within 90 days (5.5% in tenecteplase vs 11% in alteplase group, adjusted HR 0.99 (95% CI 0.96 to 1.02)). CONCLUSION: In this post-hoc analysis of patients with minor stroke enrolled in the AcT trial, safety and efficacy outcomes with tenecteplase 0.25 mg/kg were not different from alteplase 0.9 mg/kg.

Sex-Based Analysis of Workflow and Outcomes in Acute Ischemic Stroke Patients Treated With Alteplase Versus Tenecteplase.

BACKGROUND: Understanding sex differences in stroke care is important in reducing potential disparities. Our objective was to explore sex differences in workflow efficiency, treatment efficacy, and safety in the AcT trial (Alteplase Compared to Tenecteplase). METHODS: AcT was a multicenter, registry-linked randomized noninferiority trial comparing tenecteplase (0.25 mg/kg) with alteplase (0.9 mg/kg) in acute ischemic stroke within 4.5 hours of onset. In this post hoc analysis, baseline characteristics, workflow times, successful reperfusion (extended Thrombolysis in Cerebral Infarction score ≥2b), symptomatic intracerebral hemorrhage, 90-day functional independence (modified Rankin Scale score, 0-1), and 90-day mortality were compared by sex. Mixed-effects regression analysis was used adjusting for age, stroke severity, and occlusion site for outcomes. RESULTS: Of 1577 patients treated with intravenous thrombolysis (2019-2022), 755 (47.9%) were women. Women were older (median, 77 [68-86] years in women versus 70 [59-79] years in men) and had a higher proportion of severe strokes (National Institutes of Health Stroke Scale score >15; 32.4% versus 24.9%) and large vessel occlusions (28.7% versus 21.5%) compared with men. All workflow times were comparable between sexes. Women were less likely to achieve functional independence (31.7% versus 39.8%; unadjusted relative risk, 0.80 [95% CI, 0.70-0.91]) and had higher mortality (17.7% versus 13.3%; unadjusted relative risk, 1.33 [95% CI, 1.06-1.69]). Adjusted analysis showed no difference in outcomes between sexes. CONCLUSIONS: Differences in prognostic factors of age, stroke severity, and occlusion site largely accounted for higher functional dependence and mortality in women. No sex disparities were apparent in workflow quality indicators. Given the integration of the AcT trial into clinical practice, these results provide reassurance that no major sex biases are apparent in acute stroke management throughout participating Canadian centers. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03889249.

Safety and efficacy of tenecteplase versus alteplase in stroke patients with carotid tandem lesions: Results from the AcT trial.

BACKGROUND: Carotid tandem lesions ((TL) ⩾70% stenosis or occlusion) account for 15-20% of acute stroke with large vessel occlusion. AIMS: We investigated the safety and efficacy of intravenous tenecteplase (0.25 mg/kg) versus intravenous alteplase (0.9 mg/kg) in patients with carotid TL. METHODS: This is a substudy of the alteplase compared with the tenecteplase trial. Patients with ⩾70% stenosis of the extracranial internal carotid artery (ICA) and concomitant occlusion of the intracranial ICA, M1 or M2 segments of the middle cerebral artery on baseline computed tomography angiography (CTA) were included. Primary outcome was 90-day-modified Rankin Scale (mRS) 0-1. Secondary outcomes were mRS 0-2, mortality, and symptomatic ICH (sICH). Angiographic outcomes were successful recanalization (revised Arterial Occlusive Lesion (rAOL) 2b-3) on first and successful reperfusion (eTICI 2b-3) on final angiographic acquisitions. Multivariable mixed-effects logistic regression was performed. RESULTS: Among 1577 alteplase versus tenecteplase randomized controlled trial (AcT) patients, 128 (18.8%) had carotid TL. Of these, 93 (72.7%) underwent intravenous thrombolysis plus endovascular thrombectomy (IVT + EVT), while 35 (27.3%) were treated with IVT alone. In the IVT + EVT group, tenecteplase was associated with higher odds of 90-day-mRS 0-1 (46.0% vs. 32.6%, adjusted OR (aOR) 3.21; 95% CI = 1.06-9.71) compared with alteplase. No statistically significant differences in rates of mRS 0-2 (aOR 1.53; 95% CI = 0.51-4.55), initial rAOL 2b-3 (16.3% vs. 28.6%), final eTICI 2b-3 (83.7% vs. 85.7%), and mortality (18.0% vs. 16.3%) were found. SICH only occurred in one patient. There were no differences in outcomes between thrombolytic agents in the IVT-only group. CONCLUSION: In patients with carotid TL treated with EVT, intravenous tenecteplase may be associated with similar or better clinical outcomes, similar angiographic reperfusion rates, and safety outcomes as compared with alteplase.

Advance Consent in Acute Stroke Trials: Survey of Canadian Research Ethics Board Chairs.

Advance consent could allow individuals at high risk of stroke to provide consent before they might become eligible for enrollment in acute stroke trials. This survey explores the acceptability of this novel technique to Canadian Research Ethics Board (REB) chairs that review acute stroke trials. Responses from 15 REB chairs showed that majority of respondents expressed comfort approving studies that adopt advance consent. There was no clear preference for advance consent over deferral of consent, although respondents expressed significant concern with broad rather than trial-specific advance consent. These findings shed light on the acceptability of advance consent to Canadian ethics regulators.

Advance Consent in Acute Stroke Trials: Survey of Canadian Stroke Physicians.

Advance consent presents a potential solution to the challenge of obtaining informed consent for participation in acute stroke trials. Clinicians in stroke prevention clinics are uniquely positioned to identify and seek consent from potential stroke trial participants. To assess the acceptability of advance consent to Canadian stroke clinic physicians, we performed an online survey. We obtained 58 respondents (response rate 35%): the vast majority (82%) expressed comfort with obtaining advance consent and 92% felt that doing so would not be a significant disruption to clinic workflow. These results support further study of advance consent for acute stroke trials.

Association of plasma biomarkers with cognition, cognitive decline, and daily function across and within neurodegenerative diseases: Results from the Ontario Neurodegenerative Disease Research Initiative.

INTRODUCTION: We investigated whether novel plasma biomarkers are associated with cognition, cognitive decline, and functional independence in activities of daily living across and within neurodegenerative diseases. METHODS: Glial fibrillary acidic protein (GFAP), neurofilament light chain (NfL), phosphorylated tau (p-tau)181 and amyloid beta (Aß)42/40 were measured using ultra-sensitive Simoa immunoassays in 44 healthy controls and 480 participants diagnosed with Alzheimer's disease/mild cognitive impairment (AD/MCI), Parkinson's disease (PD), frontotemporal dementia (FTD) spectrum disorders, or cerebrovascular disease (CVD). RESULTS: GFAP, NfL, and/or p-tau181 were elevated among all diseases compared to controls, and were broadly associated with worse baseline cognitive performance, greater cognitive decline, and/or lower functional independence. While GFAP, NfL, and p-tau181 were highly predictive across diseases, p-tau181 was more specific to the AD/MCI cohort. Sparse associations were found in the FTD and CVD cohorts and for Aß42/40 . DISCUSSION: GFAP, NfL, and p-tau181 are valuable predictors of cognition and function across common neurodegenerative diseases, and may be useful in specialized clinics and clinical trials.

Effect of Time to Thrombolysis on Clinical Outcomes in Patients With Acute Ischemic Stroke Treated With Tenecteplase Compared to Alteplase: Analysis From the AcT Randomized Controlled Trial.

BACKGROUND: The AcT (Alteplase Compared to Tenecteplase) randomized controlled trial showed that tenecteplase is noninferior to alteplase in treating patients with acute ischemic stroke within 4.5 hours of symptom onset. The effect of time to treatment on clinical outcomes with alteplase is well known; however, the nature of this relationship is yet to be described with tenecteplase. We assessed whether the association of time to thrombolysis treatment with clinical outcomes in patients with acute ischemic stroke differs by whether they receive intravenous tenecteplase versus alteplase. METHODS: Patients included were from AcT, a pragmatic, registry-linked, phase 3 randomized controlled trial comparing intravenous tenecteplase to alteplase in patients with acute ischemic stroke. Eligible patients were >18 years old, with disabling neurological deficits, presenting within 4.5 hours of symptom onset, and eligible for thrombolysis. Primary outcome was modified Rankin Scale score 0 to 1 at 90 days. Safety outcomes included 24-hour symptomatic intracerebral hemorrhage and 90-day mortality rates. Mixed-effects logistic regression was used to assess the following: (a) the association of stroke symptom onset to needle time; (b) door (hospital arrival) to needle time with outcomes; and (c) if these associations were modified by type of thrombolytic administered (tenecteplase versus alteplase), after adjusting for age, sex, baseline stroke severity, and site of intracranial occlusion. RESULTS: Of the 1538 patients included in this analysis, 1146 (74.5%; 591 tenecteplase and 555 alteplase) presented within 3 hours versus 392 (25.5%; 196: TNK and 196 alteplase) who presented within 3 to 4.5 hours of symptom onset. Baseline patient characteristics in the 0 to 3 hours versus 3- to 4.5-hour time window were similar, except patients in the 3- to 4.5-hour window had lower median baseline National Institutes of Health Stroke Severity Scale (10 versus 7, respectively) and lower proportion of patients with large vessel occlusion on baseline CT angiography (26.9% versus 18.7%, respectively). Type of thrombolytic agent (tenecteplase versus alteplase) did not modify the association between continuous onset to needle time (Pinteraction=0.161) or door-to-needle time (Pinteraction=0.972) and primary clinical outcome. Irrespective of the thrombolytic agent used, each 30-minute reduction in onset to needle time was associated with a 1.8% increase while every 10 minutes reduction in door-to-needle time was associated with a 0.2% increase in the probability of achieving 90-day modified Rankin Scale score 0 to 1, respectively. CONCLUSIONS: The effect of time to tenecteplase administration on clinical outcomes is like that of alteplase, with faster administration resulting in better clinical outcomes. REGISTRATION: URL: https://classic. CLINICALTRIALS: gov; Unique identifier: NCT03889249.