The effect of a cognitive training therapy based on stimulation of brain oscillations in patients with mild cognitive impairment in a Chilean sample: study protocol for a phase IIb, 2 × 3 mixed factorial, double-blind randomised controlled trial

BACKGROUND

The ageing population has increased the prevalence of disabling and high-cost diseases, such as dementia and mild cognitive impairment (MCI). The latter can be considered a prodromal phase of some dementias and a critical stage for interventions to postpone the impairment of functionality. Working memory (WM) is a pivotal cognitive function, representing the fundamental element of executive functions. This project proposes an intervention protocol to enhance WM in these users, combining cognitive training with transcranial electrical stimulation of alternating current (tACS). This technique has been suggested to enhance the neuronal plasticity needed for cognitive processes involving oscillatory patterns. WM stands to benefit significantly from this approach, given its well-defined electrophysiological oscillations. Therefore, tACS could potentially boost WM in patients with neurodegenerative diseases.

METHODS

This study is a phase IIb randomised, double-blind clinical trial with a 3-month follow-up period. The study participants will be 62 participants diagnosed with MCI, aged over 60, from Valparaíso, Chile. Participants will receive an intervention combining twelve cognitive training sessions with tACS. Participants will receive either tACS or placebo stimulation in eight out of twelve training sessions. Sessions will occur twice weekly over 6 weeks. The primary outcomes will be electroencephalographic measurements through the prefrontal theta oscillatory activity, while the secondary effects will be cognitive assessments of WM. The participants will be evaluated before, immediately after, and 3 months after the end of the intervention.

DISCUSSION

The outcomes of this trial will add empirical evidence about the benefits and feasibility of an intervention that combines cognitive training with non-invasive brain stimulation. The objective is to contribute tools for optimal cognitive treatment in patients with MCI. To enhance WM capacity, postpone the impairment of functionality, and obtain a better quality of life.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05291208. Registered on 28 February 2022. ISRCTN87597719 retrospectively registered on 15 September 2023.

Cardiovascular events risk in patients with systemic autoimmune diseases: a prognostic systematic review and meta-analysis

BACKGROUND

Chronic inflammation is considered a risk factor for the development of atherosclerosis and cardiovascular (CV) events. We seek to assess the risk of CV events in patients with Systemic autoimmune diseases (SAD), such as Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA), Psoriasis (Ps) and Ankylosing Spondylitis (AS), compared with the general population.

METHODS AND RESULTS

A systematic search of MEDLINE from inception up to May 2021 was performed. Observational studies including individuals with and without autoimmune diseases (SLE, RA, Ps, AS), which reported a measure of association and variability for the effect of SAD on CV events, were included. The random effects meta-analysis was performed using the Hartung-Knapp-Sidik-Jonkman approach to obtain the pooled estimates. Cardiovascular Events including CV mortality, non-fatal myocardial infarction (MI), non-fatal stroke and coronary revascularization were the main outcomes evaluated. Fifty-four studies were selected, with a total of 24,107,072 participants. The presence of SAD was associated with an increased risk of CV mortality (HR 1.49 [95% CI 1.10-2.03]), non-fatal MI (HR 1.42 [95% CI 1.23-1.62]), and non-fatal stroke (HR 1.47 [95% CI 1.28-1.70]). RA, SLE, and Ps (particularly with arthritis) were significantly associated with a higher risk of MI and stroke. SAD was also associated with an increased risk of Major Adverse Cardiovascular Events (MACE) (HR 1.45 [95% CI 1.16-1.83]).

CONCLUSION

Patients with SAD present an increased risk of CV morbidity and mortality, which should be considered when establishing therapeutic strategies. These findings support the role of systemic inflammation in the development of atherosclerosis-driven disease.

Dilated optic nerve sheath by ultrasound predicts mortality among patients with acute intracerebral hemorrhage

BACKGROUND

Intracerebral hemorrhage (ICH) is a deadly disease and increased intracranial pressure (ICP) is associated with worse outcomes in this context.

OBJECTIVE

We evaluated whether dilated optic nerve sheath diameter (ONSD) depicted by optic nerve ultrasound (ONUS) at hospital admission has prognostic value as a predictor of mortality at 90 days.

METHODS

Prospective multicenter study of acute supratentorial primary ICH patients consecutively recruited from two tertiary stroke centers. Optic nerve ultrasound and cranial computed tomography (CT) scans were performed at hospital admission and blindly reviewed. The primary outcome was mortality at 90-days. Multivariate logistic regression, ROC curve, and C-statistics were used to identify independent predictors of mortality.

RESULTS

Between July 2014 and July 2016, 57 patients were evaluated. Among those, 13 were excluded and 44 were recruited into the trial. Their mean age was 62.3 ± 13.1 years and 12 (27.3%) were female. On univariate analysis, ICH volume on cranial CT scan, ICH ipsilateral ONSD, Glasgow coma scale, National Institute of Health Stroke Scale (NIHSS) and glucose on admission, and also diabetes mellitus and current nonsmoking were predictors of mortality. After multivariate analysis, ipsilateral ONSD (odds ratio [OR]: 6.24; 95% confidence interval [CI]: 1.18-33.01; p = 0.03) was an independent predictor of mortality, even after adjustment for other relevant prognostic factors. The best ipsilateral ONSD cutoff was 5.6mm (sensitivity 72% and specificity 83%) with an AUC of 0.71 (p = 0.02) for predicting mortality at 90 days.

CONCLUSION

Optic nerve ultrasound is a noninvasive, bedside, low-cost technique that can be used to identify increased ICP in acute supratentorial primary ICH patients. Among these patients, dilated ONSD is an independent predictor of mortality at 90 days.

Disparities in Stroke Incidence Over Time by Sex and Age in Latin America and the Caribbean Region 1997 to 2021: A Systematic Review and Meta-Analysis

Background High-income country studies show unfavorable trends in stroke incidence (SI) in younger populations. We aimed to estimate temporal change in SI disaggregated by age and sex in Latin America and the Caribbean region. Methods and Results A search strategy was used in MEDLINE, WOS, and LILACS databases from 1997 to 2021, including prospective population-based observational studies with first-ever stroke incidence in Latin America. Reports without data broken down by age and sex were excluded. Risk of bias was assessed with The Joanna Briggs Institute's guide. The main outcomes were incidence rate ratio and relative temporal trend ratio of SI, comparing time periods before 2010 with after 2010. Pooled relative temporal trend ratios considering only studies with 2 periods in the same population were calculated by random-effects meta-analysis. Meta-regression analysis was used to evaluate incidence rate determinants. From 9242 records identified, 6 studies were selected including 4483 first-ever stroke in 4 101 084 individuals. Crude incidence rate ratio in younger subjects (<55 years) comparing before 2010:after 2010 periods showed an increase in SI in the past decade (incidence rate ratio, 1.37 [95% CI, 1.23-1.50]), in contrast to a decrease in older people during the same period (incidence rate ratio, 0.83 [95% CI, 0.76-0.89]). Overall relative temporal trend ratio (<55:≥55 years) was 1.65 (95 CI%, 1.50-1.80), with higher increase in young women (pooled relative temporal trend ratio, 3.08 [95% CI, 1.18-4.97]; P for heterogeneity <0.001). Conclusions An unfavorable change in SI in young people, especially in women, was detected in population-based studies in the past decade in Latin America and the Caribbean. Further investigation of the explanatory variables is required to ameliorate stroke prevention and inform local decision-makers. Registration URL: https://www.crd.york.ac.uk/prospero/ Identifier: CRD42022332563.

Who is in the emergency room matters when we talk about door-to-needle time: a single-center experience

BACKGROUND

 The efficacy of intravenous thrombolysis (IVT) is time-dependent.

OBJECTIVE

 To compare the door-to-needle (DTN) time of stroke neurologists (SNs) versus non-stroke neurologists (NSNs) and emergency room physicians (EPs). Additionally, we aimed to determine elements associated with DTN ≤ 20 minutes.

METHODS

 Prospective study of patients with IVT treated at Clínica Alemana between June 2016 and September 2021.

RESULTS

 A total of 301 patients underwent treatment for IVT. The mean DTN time was 43.3 ± 23.6 minutes. One hundred seventy-three (57.4%) patients were evaluated by SNs, 122 (40.5%) by NSNs, and 6 (2.1%) by EPs. The mean DTN times were 40.8 ± 23, 46 ± 24.7, and 58 ± 22.5 minutes, respectively. Door-to-needle time ≤ 20 minutes occurred more frequently when patients were treated by SNs compared to NSNs and EPs: 15%, 4%, and 0%, respectively (odds ratio [OR]: 4.3, 95% confidence interval [95%CI]: 1.66-11.5, p = 0.004). In univariate analysis DTN time ≤ 20 minutes was associated with treatment by a SN (p = 0.002), coronavirus disease 2019 pandemic period (p = 0.21), time to emergency room (ER) (p = 0.21), presence of diabetes (p = 0.142), hypercholesterolemia (p = 0.007), atrial fibrillation (p < 0.09), score on the National Institutes of Health Stroke Scale (NIHSS) (p = 0.001), lower systolic (p = 0.143) and diastolic (p = 0.21) blood pressures, the Alberta Stroke Program Early CT Score (ASPECTS; p = 0.09), vessel occlusion (p = 0.05), use of tenecteplase (p = 0.18), thrombectomy (p = 0.13), and years of experience of the physician (p < 0.001). After multivariate analysis, being treated by a SN (OR: 3.95; 95%CI: 1.44-10.8; p = 0.007), NIHSS (OR: 1.07; 95%CI: 1.02-1.12; p < 0.002) and lower systolic blood pressure (OR: 0.98; 95%CI: 0.96-0.99; p < 0.003) remained significant.

CONCLUSION

 Treatment by a SN resulted in a higher probability of treating the patient in a DTN time within 20 minutes.

Genetics of spontaneous cervical and coronary artery dissections

Objectives

Spontaneous cervical artery dissections (SCeAD) and coronary artery dissections (SCoAD) are major causes of neurovascular and cardiovascular morbidity in young adults. Although multiple aspects of their etiology are still unknown, most consensuses are focused on the presence of constitutional genetic aspects and environmental triggers. Since recent evidence of genetic contribution points to a possible overlap between these conditions, we aimed to describe current information on SCeAD and SCoAD genetics and their potential shared pathological aspects.

Materials and methods

A narrative review is presented. Publications in English and Spanish were queried using database search. The articles were evaluated by one team member in terms of inclusion criteria. After collecting, the articles were categorized based on scientific content.

Results

Given that patients with SCeAD and SCoAD rarely present connective tissue disorders, other genetic loci are probably responsible for the increased susceptibility in some individuals. The common variant rs9349379 at PHACTR1 gene is associated with predisposition to pathologies of the arterial wall, likely mediated by variations in Endothelin-1 (ET-1) levels. The risk of arterial dissection may be increased for those who carry the rs9349379(A) allele, associated with lower expression levels of ET-1; however, the local effect of this vasomotor imbalance remains unclear. Sex differences seen in SCeAD and SCoAD support a role for sex hormones that could modulate risk, tilting the delicate balance and forcing vasodilator actions to prevail over vasoconstriction due to a reduction in ET-1 expression.

Conclusions

New evidence points to a common gene variation that could explain dissection in both the cervical and coronary vasculatures. To further confirm the risk conferred by the rs9349379 variant, genome wide association studies are warranted, hopefully in larger and ethnically diverse populations.

Effects of intensive blood pressure lowering on cerebral ischaemia in thrombolysed patients: insights from the ENCHANTED trial

Background

Intensive blood pressure lowering may adversely affect evolving cerebral ischaemia. We aimed to determine whether intensive blood pressure lowering altered the size of cerebral infarction in the 2196 patients who participated in the Enhanced Control of Hypertension and Thrombolysis Stroke Study, an international randomised controlled trial of intensive (systolic target 130-140 mm Hg within 1 h; maintained for 72 h) or guideline-recommended (systolic target <180 mm Hg) blood pressure management in patients with hypertension (systolic blood pressure >150 mm Hg) after thrombolysis treatment for acute ischaemic stroke between March 3, 2012 and April 30, 2018.

Methods

All available brain imaging were analysed centrally by expert readers. Log-linear regression was used to determine the effects of intensive blood pressure lowering on the size of cerebral infarction, with adjustment for potential confounders. The primary analysis pertained to follow-up computerised tomography (CT) scans done between 24 and 36 h. Sensitivity analysis were undertaken in patients with only a follow-up magnetic resonance imaging (MRI) and either MRI or CT at 24-36 h, and in patients with any brain imaging done at any time during follow-up. This trial is registered with ClinicalTrials.gov, number NCT01422616.

Findings

There were 1477 (67.3%) patients (mean age 67.7 [12.1] y; male 60%, Asian 65%) with available follow-up brain imaging for analysis, including 635 patients with a CT done at 24-36 h. Mean achieved systolic blood pressures over 1-24 h were 141 mm Hg and 149 mm Hg in the intensive group and guideline group, respectively. There was no effect of intensive blood pressure lowering on the median size (ml) of cerebral infarction on follow-up CT at 24-36 h (0.3 [IQR 0.0-16.6] in the intensive group and 0.9 [0.0-12.5] in the guideline group; log Δmean -0.17, 95% CI -0.78 to 0.43). The results were consistent in sensitivity and subgroup analyses.

Interpretation

Intensive blood pressure lowering treatment to a systolic target <140 mm Hg within several hours after the onset of symptoms may not increase the size of cerebral infarction in patients who receive thrombolysis treatment for acute ischaemic stroke of mild to moderate neurological severity.

Funding

National Health and Medical Research Council of Australia; UK Stroke Association; UK Dementia Research Institute; Ministry of Health and the National Council for Scientific and Technological Development of Brazil; Ministry for Health, Welfare, and Family Affairs of South Korea; Takeda.

Stroke in Latin America: Systematic review of incidence, prevalence, and case-fatality in 1997-2021

BACKGROUND

Stroke is a major global cause of death and disability. Most strokes occur in populations of low-middle-income country (LMIC); therefore, the subsequent disease burden is greater than in populations of high-income countries. Few epidemiological data exist for stroke in Latin America, composed primarily of LMIC.

AIMS

To determine epidemiological measures of incidence, prevalence, and 1-month case-fatality for stroke in Latin America/Caribbean (LAC) during 1997-2021.

SUMMARY OF REVIEW

A structured search was conducted to identify relevant references from MEDLINE, WOS, and LILACS databases for prospective observational and cross-sectional studies in LAC populations from January 1997 to December 2021. A total of 9242 records were screened and 12 selected for analysis, seven incidence studies and five prevalence studies. Case-fatality was reported in six articles. Sub-group analysis by age, sex, and income countries was performed. A narrative synthesis of the findings was performed. Meta-analysis was performed using random-effect model to obtain pooled estimates with 95% confidence intervals (CIs). Studies quality was assessed according to the risk of bias criteria described in the Joanna Briggs Institute's guide. The overall crude annual incidence rate of first-ever stroke in LAC was 119.0 (95% CI = 95.9-142.1)/100,000 people (with high heterogeneity between studies (I² = 98.1%)). The overall crude prevalence was 3060 (95% CI: 95.9-142.1)/100,000 people (with high heterogeneity between studies (I² = 98.8%)). The overall case-fatality at 1 month after the first stroke was 21.1% (95% CI = 18.6-23.7) (I² = 49.40%).

CONCLUSION

This review contributes to our understanding regarding the burden caused by stroke in LAC. More studies with comparable designs are needed to generate reliable data and should include both standardized criteria, such as the World Health Organization clinical criteria and updated standard methods of case assurance, data collection, and reporting.

The Role of Colchicine in Atherosclerosis: From Bench to Bedside

Inflammation is a key feature of atherosclerosis. The inflammatory process is involved in all stages of disease progression, from the early formation of plaque to its instability and disruption, leading to clinical events. This strongly suggests that the use of anti-inflammatory agents might improve both atherosclerosis progression and cardiovascular outcomes. Colchicine, an alkaloid derived from the flower Colchicum autumnale, has been used for years in the treatment of inflammatory pathologies, including Gout, Mediterranean Fever, and Pericarditis. Colchicine is known to act over microtubules, inducing depolymerization, and over the NLRP3 inflammasome, which might explain its known anti-inflammatory properties. Recent evidence has shown the therapeutic potential of colchicine in the management of atherosclerosis and its complications, with limited adverse effects. In this review, we summarize the current knowledge regarding colchicine mechanisms of action and pharmacokinetics, as well as the available evidence on the use of colchicine for the treatment of coronary artery disease, covering basic, translational, and clinical studies.

Cervical Artery Dissection in Postpartum Women after Cesarean and Vaginal Delivery

BACKGROUND AND AIMS

Cervical artery dissection (CAD) is an infrequent but potentially disabling and fatal disease, accounting for up to 25 % of strokes in young adults. Pregnancy-related hormonal changes and increased hemodynamic stress on artery walls during vaginal delivery have been associated to CAD. We aim to describe a series of women presenting CAD during postpartum (PP) after cesarean and vaginal delivery.

METHODS

CAD women admitted to one hospital in Santiago, Chile, between July 2018 and October 2020 were included in a prospective cohort. Demographic, clinical and imaging data were registered for the PP group.

RESULTS

Sixty-seven women were diagnosed with CAD, from which 10 were PP. Seven women had cesarean section and 3 had vaginal delivery. They presented CAD related symptoms after a median of 10.5 (IQR 5-15) days from delivery. All of them had headache as initial symptom, 9 presented cervical pain and 8 had a family history of stroke. Four patients presented preeclampsia during pregnancy. Acute treatment consisted mostly in antiplatelet agents and analgesics. None of these patients had a CAD related stroke. Demographic, clinical and imaging characteristics of these women with CAD during PP are described.

CONCLUSIONS

This case series underpins the importance of clinical suspicion of CAD after delivery, highlighting the fact that CAD is not limited to women with vaginal delivery, thus alternative causes beyond acute hemodynamic stress could be involved. Further research is required to determine genetic components, along with deeper knowledge of modulating factors related to CAD in this setting.

A Chilean Experience of Telestroke in a COVID-19 Pandemic Year

Background and Purpose

Telemedicine for stroke patients' care (telestroke [TS]) has grown notably in recent decades and may offer advantages during health crisis. Hospital admissions related to stroke have decreased globally during the COVID-19 pandemic, but scarce information is available regarding the effect of COVID-19 in TS. Using a population-based TS registry, we investigated the impact of the first year of the COVID-19 pandemic throughout our TS network in Santiago, Chile.

Methods

Stroke codes evaluated after the onset of COVID-19 restrictions in Chile (defined as March 15, 2020) were compared with those evaluated in 2019. We analyzed differences between number of stroke codes, thrombolysis rate, stroke severity, and time from the stroke onset to hospital admission.

Results

We observed that the number of stroke codes and the number of patients undergoing reperfusion therapy did not change significantly (p = 0.669 and 0.415, respectively). No differences were found with respect to the median time from the stroke onset to admission (p = 0.581) or in National Institutes of Health Stroke Scale (NIHSS) scores (p = 0.055). The decision-making-to-needle time was significantly shorter in the COVID-19 period (median 5 min [IQR 3–8], p < 0.016), but no significant changes were found at the other times.

Conclusions

This study demonstrates the potential of adapting TS to extreme situations such as the COVID-19 pandemic, as well as the importance of establishing networks that facilitate patient access to quality treatments.

Diffusion-weighted imaging as predictor of acute ischemic stroke etiology

BACKGROUND

Topographic patterns may correlate with causes of ischemic stroke.

OBJECTIVE

To investigate the association between diffusion-weighted imaging (DWI) and Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification.

METHODS

We included 1019 ischemic stroke patients. DWI were classified as: i) negative; ii) DWI single lesion (cortico-subcortical, cortical, subcortical ≥20 mm, or subcortical <20 mm); iii) scattered lesions in one territory (small scattered lesions or confluent with additional lesions); and iv) multiple lesions (multiple unilateral anterior circulation [MAC], multiple posterior circulation [MPC], multiple bilateral anterior circulation [MBAC], and multiple anterior and posterior circulations [MAP]).

RESULTS

There was a relationship between DWI patterns and TOAST classification (p<0.001). Large artery atherosclerosis was associated with small, scattered lesions in one vascular territory (Odds Ratio [OR] 4.22, 95% confidence interval [95%CI] 2.61-6.8), MPC (OR 3.52; 95%CI 1.54-8.03), and subcortical lesions <20 mm (OR 3.47; 95%CI 1.76-6.85). Cardioembolic strokes correlated with MAP (OR 4.3; 95%CI 1.64-11.2), cortico-subcortical lesions (OR 3.24; 95%CI 1.9-5.5) and negative DWI (OR 2.46; 95%CI 1.1-5.49). Cryptogenic strokes correlated with negative DWI (OR 4.1; 95%CI 1,84-8.69), cortical strokes (OR 3.3; 95%CI 1.25-8.8), MAP (OR 3.33; 95%CI 1.25-8.81) and subcortical lesion ≥20 mm (OR 2.44; 95%CI 1,04-5.73). Lacunar strokes correlated with subcortical lesions diameter <20 mm (OR 42.9; 95%CI 22.7-81.1) and negative DWI (OR 8.87; 95%CI 4.03-19.5). Finally, MBAC (OR 9.25; 95%CI 1.12-76.2), MAP (OR 5.54; 95%CI 1.94-15.1), and MPC (OR 3.61; 95%CI 1.5-8.7) correlated with stroke of other etiologies.

CONCLUSIONS

A relationship exists between DWI and stroke subtype.

Heart rate and cardiac autonomic responses to concomitant deep breathing, hand grip exercise, and circulatory occlusion in healthy young adult men and women

BACKGROUND

Deep breathing (DB) and handgrip (HG) exercise -with and without circulatory occlusion (OC) in muscle-, have been shown to have beneficial effects on cardiovascular function; however, the combination of these maneuvers on heart rate (HR) and cardiac sympathovagal balance have not been previously investigated. Therefore, the aim of the present study was to evaluate the effect of simultaneous DB, HG, and OC maneuvers on the sympathovagal balance in healthy women and men subjects.

METHODS AND RESULTS

Electrocardiogram and ventilation were measured in 20 healthy subjects (Women: n = 10; age = 27 ± 4 years; weight = 67.1 ± 8.4 kg; and height = 1.6 ± 0.1 m. Men: n = 10; age = 27 ± 3 years; weight = 77.5 ± 10.1 kg; and height = 1.7 ± 0.1 m) at baseline and during DB, DB + HG, or DB + HG + OC protocols. Heart rate (HR) and respiratory rate were continuously recorded, and spectral analysis of heart rate variability (HRV) were calculated to indirectly estimate cardiac autonomic function. Men and women showed similar HR responses to DB, DB + HG and DB + HG + OC. Men exhibited a significant HR decrease following DB + HG + OC protocol which was accompanied by an improvement in cardiac autonomic control evidenced by spectral changes in HRV towards parasympathetic predominance (HRV High frequency: 83.95 ± 1.45 vs. 81.87 ± 1.50 n.u., DB + HG + OC vs. baseline; p < 0.05). In women, there was a marked decrease in HR after completion of both DB + HG and DB + HG + OC tests which was accompanied by a significant increase in cardiac vagal tone (HRV High frequency: 85.29 ± 1.19 vs. 77.93 ± 0.92 n.u., DB + HG vs. baseline; p < 0.05). No adverse effects or discomfort were reported by men or women during experimental procedures. Independent of sex, combination of DB, HG, and OC was tolerable and resulted in decreases in resting HR and elevations in cardiac parasympathetic tone.

CONCLUSIONS

These data indicate that combined DB, HG and OC are effective in altering cardiac sympathovagal balance and reducing resting HR in healthy men and women.

Safety and Immunogenicity of an Inactivated Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine in a Subgroup of Healthy Adults in Chile

BACKGROUND

The development of effective vaccines against coronavirus disease 2019 is a global priority. CoronaVac is an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine with promising safety and immunogenicity profiles. This article reports safety and immunogenicity results obtained for healthy Chilean adults aged ≥18 years in a phase 3 clinical trial.

METHODS

Volunteers randomly received 2 doses of CoronaVac or placebo, separated by 2 weeks. A total of 434 volunteers were enrolled, 397 aged 18-59 years and 37 aged ≥60 years. Solicited and unsolicited adverse reactions were registered from all volunteers. Blood samples were obtained from a subset of volunteers and analyzed for humoral and cellular measures of immunogenicity.

RESULTS

The primary adverse reaction in the 434 volunteers was pain at the injection site, with a higher incidence in the vaccine than in the placebo arm. Adverse reactions observed were mostly mild and local. No severe adverse events were reported. The humoral evaluation was performed on 81 volunteers. Seroconversion rates for specific anti-S1-receptor binding domain (RBD) immunoglobulin G (IgG) were 82.22% and 84.44% in the 18-59 year age group and 62.69% and 70.37% in the ≥60 year age group, 2 and 4 weeks after the second dose, respectively. A significant increase in circulating neutralizing antibodies was detected 2 and 4 weeks after the second dose. The cellular evaluation was performed on 47 volunteers. We detected a significant induction of T-cell responses characterized by the secretion of interferon-γ (IFN-γ) upon stimulation with Mega Pools of peptides from SARS-CoV-2.

CONCLUSIONS

Immunization with CoronaVac in a 0-14 schedule in Chilean adults aged ≥18 years is safe, induces anti-S1-RBD IgG with neutralizing capacity, activates T cells, and promotes the secretion of IFN-γ upon stimulation with SARS-CoV-2 antigens.

Sex differences in treatment and outcome after stroke: Pooled analysis including 19,000 participants

OBJECTIVE

To explore the sex differences in outcomes and management after stroke using a large sample with high-quality international trial data.

METHODS

Individual participant data were obtained from 5 acute stroke randomized controlled trials. Data were obtained on demographics, medication use, in-hospital treatment, and functional outcome. Study-specific crude and adjusted models were used to estimate sex differences in outcomes and management, and then pooled using random-effects meta-analysis.

RESULTS

There were 19,652 participants, of whom 7,721 (40%) were women. After multivariable adjustments, women with ischemic stroke had higher survival at 3-6 months (odds ratio [OR] 0.82, 95% confidence interval [CI] 0.70-0.97), higher likelihood of disability (OR 1.20, 95% CI 1.06-1.36), and worse quality of life (weighted mean difference -0.07, 95% CI -0.09 to 0.04). For management, women were more likely to be admitted to an acute stroke unit (OR 1.17, 95% CI 1.01-1.34), but less likely to be intubated (OR 0.58, 95% CI 0.36-0.93), treated for fever (OR 0.82, 95% CI 0.70-0.95), or admitted to an intensive care unit (OR 0.83, 95% CI 0.74-0.93). For preadmission medications, women had higher odds of being prescribed antihypertensive agents (OR 1.22, 95% CI 1.13-1.31) and lower odds of being prescribed antiplatelets (OR 0.86, 95% CI 0.79-0.93), glucose-lowering agents (OR 0.86, 95% CI 0.78-0.94), or lipid-lowering agents (OR 0.85, 95% CI 0.77-0.94).

CONCLUSIONS

This analysis suggests that women who had ischemic stroke had better survival but were also more disabled and had poorer quality of life. Variations in hospital and out-of-hospital management may partly explain the disparities.

Impact of Evidence-Based Stroke Care on Patient Outcomes: A Multilevel Analysis of an International Study

Background

The uptake of proven stroke treatments varies widely. We aimed to determine the association of evidence‐based processes of care for acute ischemic stroke (AIS) and clinical outcome of patients who participated in the HEADPOST (Head Positioning in Acute Stroke Trial), a multicenter cluster crossover trial of lying flat versus sitting up, head positioning in acute stroke.

Methods and Results

Use of 8 AIS processes of care were considered: reperfusion therapy in eligible patients; acute stroke unit care; antihypertensive, antiplatelet, statin, and anticoagulation for atrial fibrillation; dysphagia assessment; and physiotherapist review. Hierarchical, mixed, logistic regression models were performed to determine associations with good outcome (modified Rankin Scale scores 0–2) at 90 days, adjusted for patient and hospital variables. Among 9485 patients with AIS, implementation of all processes of care in eligible patients, or “defect‐free” care, was associated with improved outcome (odds ratio, 1.40; 95% CI, 1.18–1.65) and better survival (odds ratio, 2.23; 95% CI, 1.62–3.09). Defect‐free stroke care was also significantly associated with excellent outcome (modified Rankin Scale score 0–1) (odds ratio, 1.22; 95% CI, 1.04–1.43). No hospital characteristic was independently predictive of outcome. Only 1445 (15%) of eligible patients with AIS received all processes of care, with significant regional variations in overall and individual rates.

Conclusions

Use of evidence‐based care is associated with improved clinical outcome in AIS. Strategies are required to address regional variation in the use of proven AIS treatments.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique Identifier: NCT02162017.

Acute Treatment of Stroke (Except Thrombectomy)

PURPOSE OF REVIEW

The management of patients with acute stroke has been revolutionized in recent years with the advent of new effective treatments. In this rapidly evolving field, we provide an update on the management of acute stroke excluding thrombectomy, looking to recent, ongoing, and future trials.

RECENT FINDINGS

Large definitive trials have provided insight into acute stroke care including broadening the therapeutic window for thrombolysis, alternatives to standard dose alteplase, the use of dual antiplatelet therapy early after minor ischemic stroke, and treating elevated blood pressure in intracerebral hemorrhage. Further ongoing and future trials are eagerly awaited in this ever-expanding area. Although definitive trials have led to improvements in acute stroke care, there remains a need for further research to improve our understanding of pathophysiological mechanisms underlying different stroke types with the potential for treatments to be tailored to the individual.

Cluster-Randomized, Crossover Trial of Head Positioning in Acute Stroke

BACKGROUND

The role of supine positioning after acute stroke in improving cerebral blood flow and the countervailing risk of aspiration pneumonia have led to variation in head positioning in clinical practice. We wanted to determine whether outcomes in patients with acute ischemic stroke could be improved by positioning the patient to be lying flat (i.e., fully supine with the back horizontal and the face upwards) during treatment to increase cerebral perfusion.

METHODS

In a pragmatic, cluster-randomized, crossover trial conducted in nine countries, we assigned 11,093 patients with acute stroke (85% of the strokes were ischemic) to receive care in either a lying-flat position or a sitting-up position with the head elevated to at least 30 degrees, according to the randomization assignment of the hospital to which they were admitted; the designated position was initiated soon after hospital admission and was maintained for 24 hours. The primary outcome was degree of disability at 90 days, as assessed with the use of the modified Rankin scale (scores range from 0 to 6, with higher scores indicating greater disability and a score of 6 indicating death).

RESULTS

The median interval between the onset of stroke symptoms and the initiation of the assigned position was 14 hours (interquartile range, 5 to 35). Patients in the lying-flat group were less likely than patients in the sitting-up group to maintain the position for 24 hours (87% vs. 95%, P<0.001). In a proportional-odds model, there was no significant shift in the distribution of 90-day disability outcomes on the global modified Rankin scale between patients in the lying-flat group and patients in the sitting-up group (unadjusted odds ratio for a difference in the distribution of scores on the modified Rankin scale in the lying-flat group, 1.01; 95% confidence interval, 0.92 to 1.10; P=0.84). Mortality within 90 days was 7.3% among the patients in the lying-flat group and 7.4% among the patients in the sitting-up group (P=0.83). There were no significant between-group differences in the rates of serious adverse events, including pneumonia.

CONCLUSIONS

Disability outcomes after acute stroke did not differ significantly between patients assigned to a lying-flat position for 24 hours and patients assigned to a sitting-up position with the head elevated to at least 30 degrees for 24 hours. (Funded by the National Health and Medical Research Council of Australia; HeadPoST ClinicalTrials.gov number, NCT02162017 .).

Reliability of Hand-Held Transcranial Doppler with M-mode Ultrasound in Middle Cerebral Artery Measurement

Purpose

To determine the intra- and interrater agreement of mean flow velocity (MFV) and pulsatility index (PI) measurement in middle cerebral arteries, assessed by transcranial Doppler (TCD) with M-mode.

Methods

Masked experienced neurosonologists performed TCD with M-mode using handheld probe in healthy adult volunteers. The Bland–Altman method for concordance and intraclass correlation coefficient were used.

Results

Seventy-seven healthy volunteers and seven raters participated (3 on regular TCD shift and 4 off-shift). The intrarater absolute mean difference between measurements was 5.5 cm/s [95% confidence interval (CI), 4.7–6.3] for MVF and 0.073 (95% CI, 0.063–0.083) for PI. The difference between MFV measurements was significantly higher in off-shift raters (p = 0.015). The interrater absolute mean difference between measurements was 6.5 cm/s (95% CI, 5.5–7.5) for MVF and 0.065 (95% CI, 0.059–0.071) for PI. No influence was found for the middle cerebral artery side, volunteer’s sex, or age, and there was no significant difference between raters. The intraclass correlation coefficient was 82.2% (95% CI 77.8–85.6) and 72.9% (95% CI 67.4–77.6) for MFV and PI, respectively.

Conclusions

There exists good intra- and interrater agreement in MFV and PI measurements using M-mode TCD. These results support the use of this noninvasive tool and are important for clinical and investigational purposes.

Statistical analysis plan for the Head Position in Stroke Trial (HeadPoST): An international cluster cross-over randomized trial

Background There is evidence to indicate that the lying flat head position increases cerebral blood flow and oxygenation in patients with acute ischemic stroke, but how these physiological effects translate into clinical outcomes is uncertain. The Head Position in Stroke Trial aims to determine the comparative effectiveness of lying flat (0°) compared to sitting up (≥30°) head positioning, initiated within 24 h of hospital admission for patients with acute stroke. Design An international, pragmatic, cluster-randomized, crossover, open, blinded outcome assessed clinical trial. Each hospital with an established acute stroke unit (cluster) site was required to recruit up to 140 consecutive cases of acute stroke (one phase of head positioning before immediately crossing over to the other phase of head positioning), including both acute ischemic stroke and intracerebral hemorrhage, in each randomized head position as a 'business as usual' policy. Objective To outline in detail the predetermined statistical analysis plan for the study. Methods All accumulated data will be reviewed and formally assessed. Information regarding baseline characteristics of patients, their process of care and management will be outlined, and for each item, statistically relevant descriptive elements will be described. For the trial outcomes, the most appropriate statistical comparisons are described. Results A statistical analysis plan was developed that is transparent, verifiable, and predetermined before completion of data collection. Conclusions We developed a predetermined statistical analysis plan for Head Position in Stroke Trial to avoid analysis bias arising from prior knowledge of the findings, in order to reliably quantify the benefits and harms of lying flat versus sitting up early after the onset of acute stroke. Trial registration ClinicalTrials.gov identifier NCT02162017; ANZCTR identifier ACTRN12614000483651.

Withdrawal of active treatment after intracerebral haemorrhage in the INTERACT2 study

Background

in the second Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage Trial (INTERACT2), a minority of patients received withdrawal of active treatment (WAT). We wished to determine the characteristics of these patients, and the relation of this decision-making to subsequent management and final outcome.

Methods

the INTERACT2 cohort of acute intracerebral haemorrhage (ICH) patients had a decision of WAT within 7 days after hospital admission recorded. Multivariable logistic regression was used to identify the determinants of WAT and poor outcome at 90 days, defined by modified Rankin scale (mRS) scores 3-6.

Results

of 2,779 participants with available data, WAT occurred in 121 (4%) and this was significantly associated with increasing age, greater neurological severity, larger haematoma volume, intraventricular extension and randomisation to intensive BP lowering. Compared to other patients, those with WAT had greater mortality (81/121 [67%] versus 205/2624 [8%]; P < 0.001) and survivors were more likely to be severely disabled (mRS score 4-5, 19/39 [49%] versus 695/2419 [29%]; P = 0.006).

Conclusions

WAT was undertaken in patients with recognised predictors of poor prognosis, who subsequently were more likely to die or be left with severe disability. Improved understanding of specific factors determining WAT in ICH patients might improve care delivery and outcomes.

Clinical Trial Registration

the INTERACT2 study is registered with ClinicalTrials.gov (NCT00716079).

Regional variation in acute stroke care organisation

BACKGROUND

Few studies have assessed regional variation in the organisation of stroke services, particularly health care resourcing, presence of protocols and discharge planning. Our aim was to compare stroke care organisation within middle- (MIC) and high-income country (HIC) hospitals participating in the Head Position in Stroke Trial (HeadPoST).

METHODS

HeadPoST is an on-going international multicenter crossover cluster-randomized trial of 'sitting-up' versus 'lying-flat' head positioning in acute stroke. As part of the start-up phase, one stroke care organisation questionnaire was completed at each hospital. The World Bank gross national income per capita criteria were used for classification.

RESULTS

94 hospitals from 9 countries completed the questionnaire, 51 corresponding to MIC and 43 to HIC. Most participating hospitals had a dedicated stroke care unit/ward, with access to diagnostic services and expert stroke physicians, and offering intravenous thrombolysis. There was no difference for the presence of a dedicated multidisciplinary stroke team, although greater access to a broad spectrum of rehabilitation therapists in HIC compared to MIC hospitals was observed. Significantly more patients arrived within a 4-h window of symptoms onset in HIC hospitals (41 vs. 13%; P<0.001), and a significantly higher proportion of acute ischemic stroke patients received intravenous thrombolysis (10 vs. 5%; P=0.002) compared to MIC hospitals.

CONCLUSIONS

Although all hospitals provided advanced care for people with stroke, differences were found in stroke care organisation and treatment. Future multilevel analyses aims to determine the influence of specific organisational factors on patient outcomes.

Head position and cerebral blood flow in acute ischemic stroke patients: Protocol for the pilot phase, cluster randomized, Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot)

Rationale

Few proven interventions exist for acute ischemic stroke (AIS), and most are expensive and restricted in applicability. Lying flat ‘head down’ positioning of AIS patients has been shown to increase by as much as 20%, mean cerebral blood flow velocities (CBFV) measured by transcranial Doppler (TCD) but whether this translates into clinical improvement is uncertain.

Aim

To determine if the lying flat position increases mean CBFV in the affected territory as compared to the sitting up position in AIS patients.

Methods and design

Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot) is a cluster randomized (clusters being months), assessor-blinded end-point, phase IIb trial, where consecutive adults with anterior circulation AIS within 12 h of symptom onset are positioned to a randomized position for 48 h with TCD performed serially.

Study outcomes

Primary outcome is mean CBFV on TCD at 1 and 24 h after positioning. Secondary outcomes include: serious adverse events, neurological impairment at seven days, and death and disability at 90 days.

Sample size estimates

Assuming an increase of 8.3 (SD 11.4) cm/s in average of mean CBFV when tilted from 30° to 0°, 46 clusters are required (92 patients in total) to detect a 20% increase of mean CBFV with 90% power and 5% level of significance.

Conclusion

HeadPoST pilot is a cluster randomized multicenter clinical trial investigating the effect of head positioning on mean CBFV in anterior circulation AIS.