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Background: Obtaining informed consent in people with acute stroke is complex since many, as a direct result of their stroke, lose capacity to make important decisions. Furthermore, reperfusion interventions are time dependent necessitating rapid consent. We developed four different consent approaches to facilitate recruitment of a broad range of patients in the Third International Stroke Trial (IST-3). Aims: To describe the clinical characteristics of patients recruited by different consent methods and the association between these methods and time from stroke onset to randomization. Methods: IST-3 was a randomized controlled trial of thrombolysis for acute ischemic stroke. Clinicians could use one of four consent procedures: written consent, witnessed consent, assent, or a waiver of consent. We analyzed the relationship between consent procedure and baseline variables. The effect of consent procedure on delay time from onset to randomization was determined using analysis of variance to adjust for confounding effects. Results: Of the 3035 patients recruited, the method of consent was known for 3034 (99.9%), and it was written in 985 subjects (32.5%), witnessed verbal consent in 280 (9.2%), assent by relative in 1727 (56.9%), and waiver of consent in 42 subjects (1.4%). Assent was required in 63.4% for those presenting 0–3 h from stroke onset (written consent in 25.3%). Patients with more severe neurological deficits (or with a non-lacunar hemispheric stroke syndrome) were less likely to give written consent. Mean delay between onset and randomization varied significantly between consent types (one-way analysis of variance: F = 15.7 on 3 df, p < 0.0001) (longest at 4.06 h for signed consent and 3.46 h for waiver of consent). Conclusions: Acute stroke trials requiring written informed consent would result in substantial selection bias. Flexible consent methods will ensure a broad range of patients are recruited, enabling trial results to be widely generalizable. Registration: This study's registered number is ISRCTN25765518. [ABSTRACT FROM AUTHOR]

Background: We explored the influence of low-dose intravenous alteplase and intensive blood pressure lowering on outcomes of acute ischemic stroke according to status/location of vascular obstruction in participants of the Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED). Methods: ENCHANTED was a multicenter, quasi-factorial, randomized trial to determine efficacy and safety of low- versus standard-dose intravenous alteplase and intensive- versus guideline-recommended blood pressure lowering in acute ischemic stroke patients. In those who had baseline computed tomography or magnetic resonance imaging angiography, the degree of vascular occlusion was grouped according to being no (NVO), medium (MVO), or large (LVO). Logistic regression models were used to determine 90-day outcomes (modified Rankin scale [mRS] shift [primary], other mRS cut-scores, intracranial hemorrhage, early neurologic deterioration, and recanalization) by vascular obstruction status/site. Heterogeneity in associations for outcomes across subgroups was estimated by adding an interaction term to the models. Results: There were 940 participants: 607 in alteplase arm only, 243 in blood pressure arm only, and 90 assigned to both arms. Compared to the NVO group, functional outcome was worse in LVO (mRS shift, adjusted OR [95% CI] 2.13 [1.56–2.90]) but comparable in MVO (1.34 [0.96–1.88]) groups. There were no differences in associations of alteplase dose or blood pressure lowering and outcomes across NVO/MVO/LVO groups (mRS shift: low versus standard alteplase dose 0.84 [0.54–1.30]/0.48 [0.25–0.91]/0.99 [0.75–2.09], Pinteraction = 0.28; intensive versus standard blood pressure lowering 1.32 [0.74–2.38]/0.78 [0.31–1.94]/1.24 [0.64–2.41], Pinteraction = 0.41), except for a borderline significant difference for intensive blood pressure lowering and increased early neurologic deterioration (0.63 [0.14–2.72]/0.17 [0.02–1.47]/2.69 [0.90–8.04], Pinteraction = 0.05). Conclusions: Functional outcome by dose of alteplase or intensity of blood pressure lowering is not modified by vascular obstruction status/site according to analyses from ENCHANTED, although these results are compromised by low statistical power. Clinical Trial Registration: http://www.clinicaltrials.gov. Unique identifiers: NCT01422616 [ABSTRACT FROM AUTHOR]

Background and aims: The structured, simplified modified Rankin scale questionnaire (smRSq) may increase reliability over the interrogative approach to scoring the modified Rankin scale (mRS) in acute stroke research and practice. During the conduct of the alteplase-dose arm of the international ENhanced Control of Hypertension ANd Thrombolysis StrokE stuDy (ENCHANTED), we had an opportunity to compare each of these approaches to outcome measurement. Methods: Baseline demographic data were recorded together with the National Institutes of Health Stroke Scale (NIHSS). Follow-up measures obtained at 90 days included mRS, smRSq, and the 5-Dimension European Quality of life scale (EQ-5D). Agreements between smRSq and mRS were assessed with the Kappa statistic. Multiple logistic regression was used to identify baseline predictors of Day 90 smRSq and mRS scores. Treatment effects, based on Day 90 smRSq/mRS scores, were tested in logistic and ordinal logistic regression models. Results: SmRSq and mRS scores had good agreement (weighted Kappa 0.79, 95% confidence interval (CI) 0.78–0.81), while variables of age, atrial fibrillation, diabetes mellitus, pre-morbid mRS (1 vs. 0), baseline NIHSS scores, and imaging signs of cerebral ischemia, similarly predicted their scores. Odds ratios for death or disability, and ordinal shift, 90-day mRS scores using smRSq were 1.05 (95% CI 0.91–1.20; one-sided P = 0.23 for non-inferiority) and 0.98 (95% CI 0.87–1.11; P = 0.02 for non-inferiority), similar to those using mRS. Conclusions: This study demonstrates the utility of the smRSq in a large, ethnically diverse clinical trial population. Scoring of the smRSq shows adequate agreement with the standard mRS, thus confirming it is a reliable, valid, and useful alternative measure of functional status after acute ischemic stroke. Clinical Trial registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01422616. [ABSTRACT FROM AUTHOR]

Background: The ENhanced Control of Hypertension And Thrombolysis strokE study (ENCHANTED) trial was initiated as a 2 × 2 partial-factorial active-comparison, prospective, randomized, open, blinded endpoint clinical trial to evaluate in thrombolysis-eligible acute ischemic stroke (AIS) patients whether: (1) Arm A – low-dose (0.6 mg/kg body weight) intravenous (iv) alteplase has noninferior efficacy and lower risk of symptomatic intracerebral hemorrhage (sICH) compared with standard-dose (0.9 mg/kg body weight) iv alteplase; and (2) Arm B – early intensive blood pressure (BP) lowering (systolic target 130–140 mmHg) has superior efficacy and lower risk of ICH compared with guideline-recommended BP control (systolic target <180 mmHg). Arm A was completed in 2016; Arm B is now concluding. Objective: To outline in detail and make public the predetermined statistical analysis plan (SAP) for the 'BP control' arm of this study. Methods: All data collected by participating researchers will be reviewed and formally assessed. Information pertaining to the baseline characteristics of patients, their process of care, and the delivery of treatments will be outlined, and for each item, statistically relevant descriptive elements will be described. For the trial outcomes, the most appropriate statistical comparisons to be made between groups are planned and described. Results: A SAP was developed for the results of the BP control arm of this study that is transparent, available to the public, verifiable, and predetermined before completion of data collection. Conclusions: We have developed a predetermined SAP for the ENCHANTED BP control arm to be followed to avoid analysis bias arising from prior knowledge of the study findings. Clinical trial registration: ClinicalTrials.gov (NCT01422616); ISRCTN Register (ISRCTN82387104); Australian New Zealand Clinical Trial Registry (ACTRN12611000236998); EU Clinical Trials Register (2011-005545-12); and Clinical Trials Registry – India (REF/2017/05/014334). [ABSTRACT FROM AUTHOR]

Higher blood pressure, blood pressure variability, and leukoaraiosis are risk factors for early adverse events and poor functional outcome after ischemic stroke, but prior studies differed on whether leukoaraiosis was associated with blood pressure variability, including in ischemic stroke.In the Third International Stroke Trial, blood pressure was measured in the acute phase of ischemic stroke immediately prior to randomization, and at 0.5, 1, and 24 h after randomization. Masked neuroradiologists rated index infarct, leukoaraiosis, and atrophy on CT using validated methods. We characterized blood pressure variation by coefficient of variance and three other standard methods. We measured associations between blood pressure, blood pressure variability, and leukoaraiosis using generalized estimating equations, adjusting for age, and a number of covariates related to treatment and stroke type/severity.Among 3017 patients, mean (±SD) systolic and diastolic blood pressure decreased from 155(±24)/82(±15) mmHg pre-randomization to 146(±23)/78(±14) mmHg 24 h later (P < 0.005). Mean within-subject coefficient of variance was 0.09 ± 0.05 for systolic and 0.11 ± 0.06 for diastolic blood pressure. Patients with most leukoaraiosis were older and had higher blood pressure than those with least (P < 0.0001). Although statistically significant in simple pairwise comparisons, no measures of blood pressure variability were associated with leukoaraiosis when adjusting for confounding variables (P > 0.05), e.g. age.Our results suggest that blood pressure variability is not a potential mechanism to explain the association between leukoaraiosis and poor outcome after acute stroke. [ABSTRACT FROM AUTHOR]

Background The recommended maximum age and time window for intravenous alteplase treatment of acute ischemic stroke differs between the Europe Union and United States. Aims We compared the effects of alteplase in cohorts defined by the current Europe Union or United States marketing approval labels, and by hypothetical revisions of the labels that would remove the Europe Union upper age limit or extend the United States treatment time window to 4.5 h. Methods We assessed outcomes in an individual-patient-data meta-analysis of eight randomized trials of intravenous alteplase (0.9 mg/kg) versus control for acute ischemic stroke. Outcomes included: excellent outcome (modified Rankin score 0–1) at 3–6 months, the distribution of modified Rankin score, symptomatic intracerebral hemorrhage, and 90-day mortality. Results Alteplase increased the odds of modified Rankin score 0–1 among 2449/6136 (40%) patients who met the current European Union label and 3491 (57%) patients who met the age-revised label (odds ratio 1.42, 95% CI 1.21−1.68 and 1.43, 1.23−1.65, respectively), but not in those outside the age-revised label (1.06, 0.90−1.26). By 90 days, there was no increased mortality in the current and age-revised cohorts (hazard ratios 0.98, 95% CI 0.76−1.25 and 1.01, 0.86–1.19, respectively) but mortality remained higher outside the age-revised label (1.19, 0.99–1.42). Similarly, alteplase increased the odds of modified Rankin score 0-1 among 1174/6136 (19%) patients who met the current US approval and 3326 (54%) who met a 4.5-h revised approval (odds ratio 1.55, 1.19−2.01 and 1.37, 1.17−1.59, respectively), but not for those outside the 4.5-h revised approval (1.14, 0.97−1.34). By 90 days, no increased mortality remained for the current and 4.5-h revised label cohorts (hazard ratios 0.99, 0.77−1.26 and 1.02, 0.87–1.20, respectively) but mortality remained higher outside the 4.5-h revised approval (1.17, 0.98–1.41). Conclusions An age-revised European Union label or 4.5-h-revised United States label would each increase the number of patients deriving net benefit from alteplase by 90 days after acute ischemic stroke, without excess mortality. [ABSTRACT FROM AUTHOR]

Background Most stroke research is conducted in high income countries, yet most stroke occurs in low- and middle-income countries. There is an urgent need to build stroke research capacity in low- and middle-income countries. Aims To review the global health literature on how to improve research capacity in low- and middle-income countries, provide additional data from the recently completed ATTEND Trial and provide examples from our own experience. Summary of review The main themes from our literature review were: manpower and workload, research training, research question and methodology and research funding. The literature and our own experience emphasized the importance of local stakeholders to ensure that the research was appropriate, that there were robust local ethics and regulatory processes, and research was conducted by trained personnel. Research training opportunities can be developed locally, or internationally, with many international schemes available to help support new researchers from low- and middle-income country settings. International collaboration can successfully leverage funding from high income countries that not only generate data for the local country, but also provide new data appropriate to high income countries. Conclusions Building stroke research capacity in low- and middle-income countries will be vital in improving global health given the huge burden of stroke in these countries. [ABSTRACT FROM AUTHOR]

Background: Research studies may have limited generalizability when survivors of stroke with physical, language, or cognitive impairments are excluded. Aims: To assess whether presence of cognitive, language, or global impairments affects participation in self-management programs. Methods: Stroke survivors were recruited in South Australia from seven hospitals or via advertisements into a randomized controlled trial (1:1:1 ratio) of a Stroke Self-Management Program, the Stanford chronic condition self-management program, or standard care. Impairment status was measured using: Cognistat (cognition), Frenchay Aphasia assessment (language), modified Rankin Score (mRS; where score 3-5 = global disability). Primary outcomes: participation (i.e. booked, accessed, and completed a program (defined as attending ≥ 50% of sessions)) and safety (i.e. adverse events). Outcomes were compared by impairment status. Results: Among 315 people screened 143/149 eligible were randomized (median age 71 years; 41% male; with impairments: 62% cognitive, 34% language, 64% global disability). Participation did not differ by cognitive or language impairment status (cognitive 75%, no cognitive 68%, p = 0.54; language 78%, no language 69%, p = 0.42). However, participation did vary by global impairment status (global disability 61%, no disability 96%, p < 0.001). Participants with cognitive impairment experienced more adverse events (severe n = 9 versus no cognitive impairment n = 1). Conclusion: Survivors of stroke with cognitive, language, or global impairments are able to participate in self-management programs and should be included in these types of research studies or programs. Reduced participation by those with global disability and the possibility of more adverse events in people with cognitive impairments needs to be considered. [ABSTRACT FROM AUTHOR]

Background: In low- and middle-income countries, few patients receive organized rehabilitation after stroke, yet the burden of chronic diseases such as stroke is increasing in these countries. Affordable models of effective rehabilitation could have a major impact. The ATTEND trial is evaluating a family-led caregiver delivered rehabilitation program after stroke. Objective: To publish the detailed statistical analysis plan for the ATTEND trial prior to trial unblinding. Methods: Based upon the published registration and protocol, the blinded steering committee and management team, led by the trial statistician, have developed a statistical analysis plan. The plan has been informed by the chosen outcome measures, the data collection forms and knowledge of key baseline data. Results: The resulting statistical analysis plan is consistent with best practice and will allow open and transparent reporting. Conclusions: Publication of the trial statistical analysis plan reduces potential bias in trial reporting, and clearly outlines pre-specified analyses. [ABSTRACT FROM AUTHOR]