Prevention of stroke: a strategic global imperative

The increasing global stroke burden strongly suggests that currently implemented primary stroke prevention strategies are not sufficiently effective, and new primary prevention strategies with larger effect sizes are needed. Here, we review the latest stroke epidemiology literature, with an emphasis on the recently published Global Burden of Disease 2013 Study estimates; highlight the problems with current primary stroke and cardiovascular disease (CVD) prevention strategies; and outline new developments in primary stroke and CVD prevention. We also suggest key priorities for the future, including comprehensive prevention strategies that target people at all levels of CVD risk; implementation of an integrated approach to promote healthy behaviours and reduce health disparities; capitalizing on information technology to advance prevention approaches and techniques; and incorporation of culturally appropriate education about healthy lifestyles into standard education curricula early in life. Given the already immense and fast-increasing burden of stroke and other major noncommunicable diseases (NCDs), which threatens worldwide sustainability, governments of all countries should develop and implement an emergency action plan addressing the primary prevention of NCDs, possibly including taxation strategies to tackle unhealthy behaviours that increase the risk of stroke and other NCDs.

Neurology 2016

Testing patients during seizures: A European consensus procedure developed by a joint taskforce of the ILAE – Commission on European Affairs and the European Epilepsy Monitoring Unit Association

There is currently no international consensus procedure for performing comprehensive periictal testing of patients in the epilepsy monitoring units (EMUs). Our primary goal was to develop a standardized procedure for managing and testing patients during and after seizures in EMUs. The secondary goal was to assess whether it could be implemented in clinical practice (feasibility). A taskforce was appointed by the International League Against Epilepsy (ILAE)—Commission on European Affairs and the European Epilepsy Monitoring Unit Association, to develop a standardized ictal testing battery (ITB) based on expert opinion and experience with various local testing protocols. ITB contains a comprehensive set of 10 items that evidence the clinically relevant semiologic features, and it is adaptive to the dynamics of the individual seizures. The feasibility of the ITB was prospectively evaluated on 250 seizures from 152 consecutive patients in 10 centers. ITB was successfully implemented in clinical practice in all 10 participating centers and was considered feasible in 93% of the tested seizures. ITB was not feasible for testing seizures of very short duration

Epilepsia 2016

Prospective, open-label safety study of intravenous recombinant tissue plasminogen activator in wake-up stroke

Objective

It is estimated that one of four ischemic strokes are noticed upon awakening and are not candidates for intravenous recombinant tissue plasminogen activator (rtPA) because their symptoms are >3 hours from last seen normal (LSN). We tested the safety of rtPA in a multicenter, single-arm, prospective, open-label study (NCT01183533) in patients with wake-up stroke (WUS).

Methods

We aimed to enroll 40 WUS patients with disabling deficits. Patients were 18 to 80 years of age, National Institutes of Health Stroke Scale (NIHSS) ≤25, and selected only on the appearance of noncontrast computed tomography (ie, over one-third middle cerebral artery territory hypodensity). Standard-dose (0.9mg/kg) intravenous rtPA had to be started ≤3 hours of patient awakening. The primary safety outcome was symptomatic intracerebral hemorrhage (sICH) with preplanned stopping rules and data safety board oversight. Other endpoints included: asymptomatic intracerebral hemorrhage; clinical improvement in NIHSS; and 90-day modified Rankin Scale (mRS) score.

Results

Between October 2010 and October 2013, all 40 preplanned patients were enrolled (50% men) at five stroke centers. Four patients (10%) were subsequently determined to be mimics. Patients had a mean age of 60.8, median NIHSS of 6.5 (range, 2–24), and received thrombolysis at a mean time of 10.3 ± 2.6 LSN and 2.6 ± 0.6 hours from awakening with deficits. No sICH or parenchymal hematomas occurred. At 3 months, 20 of 38 (52.6%) patients achieved excellent recovery with mRS scores of 0 or 1 (2 patients were lost to follow-up).

Interpretation

Intravenous thrombolysis was safe in this prospective WUS study of patients selected by noncontrast CT. A randomized effectiveness trial appears feasible using a similar, pragmatic design.

Ann Neurol 2016

Distinct Subtypes of Behavioral Variant Frontotemporal Dementia Based on Patterns of Network Degeneration F

Importance  Clearer delineation of the phenotypic heterogeneity within behavioral variant frontotemporal dementia (bvFTD) will help uncover underlying biological mechanisms and improve clinicians’ ability to predict disease course and to design targeted management strategies.

Objective  To identify subtypes of bvFTD syndrome based on distinctive patterns of atrophy defined by selective vulnerability of specific functional networks targeted in bvFTD using statistical classification approaches.

Design, Setting and Participants  In this retrospective observational study, 90 patients meeting the Frontotemporal Dementia Consortium consensus criteria for bvFTD underwent evaluation at the Memory and Aging Center of the Department of Neurology at University of California, San Francisco. Patients underwent a multidisciplinary clinical evaluation, including clinical demographics, genetic testing, symptom evaluation, neurologic examination, neuropsychological bedside testing, and socioemotional assessments. All patients underwent structural magnetic resonance imaging at their earliest evaluation at the memory clinic. From each patient’s structural imaging scans, the mean volumes of 18 regions of interest (ROI) constituting the functional networks specifically vulnerable in bvFTD, including the salience network (SN), with key nodes in the frontoinsula and pregenual anterior cingulate, and the semantic appraisal network (SAN), anchored in the anterior temporal lobe and subgenual cingulate, were estimated. Principal component and cluster analyses of ROI volumes were used to identify patient clusters with anatomically distinct atrophy patterns. Data were collected from from June 19, 2002, to January 13, 2015.

Main Outcomes and Measures  Evaluation of brain morphology and other clinical features, including presenting symptoms, neurologic examination signs, neuropsychological performance, rate of dementia progression, and socioemotional function, in each patient cluster.

Results  Ninety patients (54 men [60%]; 36 women [40%]; mean [SD] age at evaluation, 55.1 [9.7] years) were included in the analysis. Four subgroups of patients with bvFTD with distinct anatomic patterns of network degeneration were identified, including 2 salience network–predominant subgroups (frontal/temporal [SN-FT] and frontal [SN-F]), a semantic appraisal network–predominant group (SAN), and a subcortical-predominant group. Subgroups demonstrated distinct patterns of cognitive, socioemotional, and motor symptoms, as well as genetic compositions and estimated rates of disease progression.

Conclusions and Relevance  Divergent patterns of vulnerability in specific functional network components make an important contribution to the clinical heterogeneity of bvFTD. The data-driven anatomic classification identifies biologically meaningful anatomic phenotypes and provides a replicable approach to disambiguate the bvFTD syndrome.

JAMA Neurology 2016

Characterization of a Subtype of Autoimmune Encephalitis With Anti–Contactin-Associated Protein-like 2 Antibodies in the Cerebrospinal Fluid, Prominent Limbic Symptoms, and Seizures

Importance  Autoantibodies against contactin-associated protein-like 2 (CASPR2) are observed in several neurological syndromes, including neuromyotonia (NMT), Morvan syndrome (MoS), and limbic encephalitis.

Objective  To characterize the clinical and biological presentations of patients with anti-CASPR2 antibodies in the cerebrospinal fluid (CSF).

Design, Setting, and Participants  We conducted a retrospective cohort analysis of 18 patients who had anti-CASPR2 antibodies in their CSF between March 2009 and November 2015 at the Centre National de Référence pour les Syndromes Neurologiques Paranéoplasiques in Lyon, France. Additionally, we analyzed 15 patients who were diagnosed as having NMT or MoS as a comparative group.

Main Outcomes and Measures  Clinical presentations, anti-CASPR2 antibodies specificities, brain magnetic resonance imaging, and CSF analyses, cancer prevalence, and evolution.

Results  In this cohort of 18 patients with anti-CASPR2 antibodies in their CSF, 17 (94.4%) were male and had a median (range) age of 64.5 (53-75) years; in the second group, 9 of 15 patients (60.0%) with NMT or MoS were male and had a median (range) age of 51 years (1 month to 75 years). Only 3 patients (16.7%) in this cohort had a previous or concomitant history of cancer (prostate, hematological, or thyroid), whereas 9 patients (60.0%) in the second group had a malignant thymoma. Symptoms of limbic encephalitis were observed in all patients, including temporal lobe seizures in 16 patients (88.9%) and memory disorders in 17 patients (94.4%) from the cohort. Extralimbic signs were also evident in 12 of 18 patients (66.7%), including cerebellar ataxia in 6 patients (33.3%). Only 2 patients (11.1%) from the cohort were diagnosed as having NMT. Brain magnetic resonance imaging displayed T2-weighted temporolimbic abnormalities in 14 of 15 patients (93.3%) in the second group. Cerebrospinal fluid analysis was abnormal in 9 of 12 patients (75.0%). For 16 of 18 patients (88.9%), follow-up was performed for at least a 6-month period (median [range], 34 [11-114] months). Of these, 15 (93.8%) improved and 6 (37.5%) relapsed. In all patients in this cohort, IgG4 autoantibodies were detected in the CSF. Anti-CASPR2 antibodies in the CSF targeted the laminin G1 and discoidin domains of CASPR2 in all patients. Importantly, anti-CASPR2 antibodies were detected in the serum but not in the CSF of all patients with NMT or MoS.

Conclusions and Relevance  In this cohort study, anti-CASPR2 antibodies in the CSF are associated with a subtype of autoimmune encephalitis with prominent limbic involvement and seizures that is rarely associated with cancer. Conversely, patients with NMT and MoS have anti-CASPR2 antibodies only in the serum but not in the CSF and frequently present with a malignant thymoma. The anti-CASPR2 antibodies found in these patients targeted the discoidin and laminin G1 domains of CASPR2 and always included IgG4 autoantibodies.

JAMA Neurology 2016

Effects of alteplase on survival after ischaemic stroke (IST-3): 3 year follow-up of a randomised, controlled, open-label trial

Summary

Background

The effect of alteplase on patient survival after ischaemic stroke is the subject of debate. We report the effect of intravenous alteplase on long-term survival after ischaemic stroke of participants in the Third International Stroke Trial (IST-3).

Methods

In IST-3, done at 156 hospitals in 12 countries (Australia, Europe, and the UK), participants (aged >18 years) were randomly assigned with a telephone voice-activated or web-based system in a 1:1 ratio to treatment with intravenous 0·9 mg/kg alteplase plus standard care or standard care alone within 6 h of ischaemic stroke. We followed up participants in the UK and Scandinavia (Sweden and Norway) for survival up to 3 years after randomisation using data from national registries and compared survival in the two groups with proportional hazards survival analysis, adjusting for key prognostic variables. IST-3 is registered with the ISRCTN registry, number ISRCTN25765518.

Findings

Between May 5, 2000, and July 27, 2011, 3035 participants were enrolled in IST-3. Of these, 1948 (64%) of 3035 participants were scheduled for analysis of 3 year survival, and 1946 (>99%) of these were included in the analysis (967 [50%] in the alteplase plus standard care group and 979 [50%] in the standard care alone group). By 3 years after randomisation, 453 (47%) of 967 participants in the alteplase plus standard care group and 494 (50%) of 979 in the standard care alone group had died (risk difference 3·6% [95% CI −0·8 to 8·1]). Participants allocated to alteplase had a significantly higher hazard of death during the first 7 days (99 [10%] of 967 died in the alteplase plus standard care group vs 65 [7%] of 979 in the standard care alone group; hazard ratio 1·52 [95% CI 1·11–2·08]; p=0·004) and a significantly lower hazard of death between 8 days and 3 years (354 [41%] of 868 vs429 [47%] of 914; 0·78 [0·68–0·90]; p=0·007).

Interpretation

Alteplase treatment within 6 h after ischaemic stroke was associated with a small, non-significant reduction in risk of death at 3 years, but among individuals who survived the acute phase, treatment was associated with a significant increase in long-term survival. These results are reassuring for clinicians who have expressed concerns about the effect of alteplase on survival.

Lancet Neurology 2016

Chronic migraine headache prevention with noninvasive vagus nerve stimulation The EVENT study

Objective: To evaluate the feasibility, safety, and tolerability of noninvasive vagus nerve stimulation (nVNS) for the prevention of chronic migraine (CM) attacks.

Methods: In this first prospective, multicenter, double-blind, sham-controlled pilot study of nVNS in CM prophylaxis, adults with CM (≥15 headache d/mo) entered the baseline phase (1 month) and were subsequently randomized to nVNS or sham treatment (2 months) before receiving open-label nVNS treatment (6 months). The primary endpoints were safety and tolerability. Efficacy endpoints in the intent-to-treat population included change in the number of headache days per 28 days and acute medication use.

Results: Fifty-nine participants (mean age, 39.2 years; mean headache frequency, 21.5 d/mo) were enrolled. During the randomized phase, tolerability was similar for nVNS (n = 30) and sham treatment (n = 29). Most adverse events were mild/moderate and transient. Mean changes in the number of headache days were −1.4 (nVNS) and −0.2 (sham) (Δ = 1.2; p = 0.56). Twenty-seven participants completed the open-label phase. For the 15 completers initially assigned to nVNS, the mean change from baseline in headache days after 8 months of treatment was −7.9 (95% confidence interval −11.9 to −3.8; p < 0.01).

Conclusions: Therapy with nVNS was well-tolerated with no safety issues. Persistent prophylactic use may reduce the number of headache days in CM; larger sham-controlled studies are needed.

ClinicalTrials.gov identifier: NCT01667250.

Classification of evidence: This study provides Class II evidence that for patients with CM, nVNS is safe, is well-tolerated, and did not significantly change the number of headache days. This pilot study lacked the precision to exclude important safety issues or benefits of nVNS.

Neurology 2016