Cerebral microbleeds and stroke risk after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies

BACKGROUND

Cerebral microbleeds are a neuroimaging biomarker of stroke risk. A crucial clinical question is whether cerebral microbleeds indicate patients with recent ischaemic stroke or transient ischaemic attack in whom the rate of future intracranial haemorrhage is likely to exceed that of recurrent ischaemic stroke when treated with antithrombotic drugs. We therefore aimed to establish whether a large burden of cerebral microbleeds or particular anatomical patterns of cerebral microbleeds can identify ischaemic stroke or transient ischaemic attack patients at higher absolute risk of intracranial haemorrhage than ischaemic stroke.

METHODS

We did a pooled analysis of individual patient data from cohort studies in adults with recent ischaemic stroke or transient ischaemic attack. Cohorts were eligible for inclusion if they prospectively recruited adult participants with ischaemic stroke or transient ischaemic attack; included at least 50 participants; collected data on stroke events over at least 3 months follow-up; used an appropriate MRI sequence that is sensitive to magnetic susceptibility; and documented the number and anatomical distribution of cerebral microbleeds reliably using consensus criteria and validated scales. Our prespecified primary outcomes were a composite of any symptomatic intracranial haemorrhage or ischaemic stroke, symptomatic intracranial haemorrhage, and symptomatic ischaemic stroke. We registered this study with the PROSPERO international prospective register of systematic reviews, number CRD42016036602.

FINDINGS

Between Jan 1, 1996, and Dec 1, 2018, we identified 344 studies. After exclusions for ineligibility or declined requests for inclusion, 20 322 patients from 38 cohorts (over 35 225 patient-years of follow-up; median 1·34 years [IQR 0·19-2·44]) were included in our analyses. The adjusted hazard ratio [aHR] comparing patients with cerebral microbleeds to those without was 1·35 (95% CI 1·20-1·50) for the composite outcome of intracranial haemorrhage and ischaemic stroke; 2·45 (1·82-3·29) for intracranial haemorrhage and 1·23 (1·08-1·40) for ischaemic stroke. The aHR increased with increasing cerebral microbleed burden for intracranial haemorrhage but this effect was less marked for ischaemic stroke (for five or more cerebral microbleeds, aHR 4·55 [95% CI 3·08-6·72] for intracranial haemorrhage vs 1·47 [1·19-1·80] for ischaemic stroke; for ten or more cerebral microbleeds, aHR 5·52 [3·36-9·05] vs 1·43 [1·07-1·91]; and for ≥20 cerebral microbleeds, aHR 8·61 [4·69-15·81] vs 1·86 [1·23-1·82]). However, irrespective of cerebral microbleed anatomical distribution or burden, the rate of ischaemic stroke exceeded that of intracranial haemorrhage (for ten or more cerebral microbleeds, 64 ischaemic strokes [95% CI 48-84] per 1000 patient-years vs 27 intracranial haemorrhages [17-41] per 1000 patient-years; and for ≥20 cerebral microbleeds, 73 ischaemic strokes [46-108] per 1000 patient-years vs 39 intracranial haemorrhages [21-67] per 1000 patient-years).

INTERPRETATION

In patients with recent ischaemic stroke or transient ischaemic attack, cerebral microbleeds are associated with a greater relative hazard (aHR) for subsequent intracranial haemorrhage than for ischaemic stroke, but the absolute risk of ischaemic stroke is higher than that of intracranial haemorrhage, regardless of cerebral microbleed presence, antomical distribution, or burden.

FUNDING

British Heart Foundation and UK Stroke Association.

Recanalization Therapies in Acute Ischemic Stroke Patients

Background—

We explored the safety of intravenous thrombolysis (IVT) or intra-arterial treatment (IAT) in patients with ischemic stroke on non-vitamin K antagonist oral anticoagulants (NOACs, last intake <48 hours) in comparison with patients (1) taking vitamin K antagonists (VKAs) or (2) without previous anticoagulation (no-OAC).

Methods and Results—

This is a multicenter cohort pilot study. Primary outcome measures were (1) occurrence of intracranial hemorrhage (ICH) in 3 categories: any ICH (ICH any ), symptomatic ICH according to the criteria of the European Cooperative Acute Stroke Study II (ECASS-II) (sICH ECASS-II ) and the National Institute of Neurological Disorders and Stroke (NINDS) thrombolysis trial (sICH NINDS ); and (2) death (at 3 months). Cohorts were compared by using propensity score matching. Our NOAC cohort comprised 78 patients treated with IVT/IAT and the comparison groups of 441 VKA patients and 8938 no-OAC patients. The median time from last NOAC intake to IVT/IAT was 13 hours (interquartile range, 8–22 hours). In VKA patients, median pre-IVT/IAT international normalized ratio was 1.3 (interquartile range, 1.1–1.6). ICH any was observed in 18.4% NOAC patients versus 26.8% in VKA patients and 17.4% in no-OAC patients. sICH ECASS-II and sICH NINDS occurred in 2.6%/3.9% NOAC patients, in comparison with 6.5%/9.3% of VKA patients and 5.0%/7.2% of no-OAC patients, respectively. At 3 months, 23.0% of NOAC patients in comparison with 26.9% of VKA patients and 13.9% of no-OAC patients had died. Propensity score matching revealed no statistically significant differences.

Conclusions—

IVT/IAT in selected patients with ischemic stroke under NOAC treatment has a safety profile similar to both IVT/IAT in patients on subtherapeutic VKA treatment or in those without previous anticoagulation. However, further prospective studies are needed, including the impact of specific coagulation tests.

Serum neurofilament light chain in patients with acute cerebrovascular events

BACKGROUND AND PURPOSE

Serum neurofilaments are markers of axonal injury. We addressed their diagnostic and prognostic role in acute ischemic stroke (AIS) and transient ischemic attack (TIA).

METHODS

Nested within a prospective cohort study, we compared levels of serum neurofilament light chain (sNfL) drawn within 24 h from symptom onset in patients with AIS or TIA. Patients without magnetic resonance imaging on admission were excluded. We assessed whether sNfL was associated with: (i) clinical severity on admission, (ii) diagnosis of AIS vs. TIA, (iii) infarct size on admission magnetic resonance diffusion-weighted imaging (MR-DWI) and (iv) functional outcome at 3 months.

RESULTS

We analyzed 504 patients with AIS and 111 patients with TIA. On admission, higher National Institutes of Health Stroke Scale (NIHSS) scores were associated with higher sNfL: NIHSS score < 7, 13.1 pg/mL [interquartile range (IQR), 5.3-27.8]; NIHSS score 7-15, 16.7 pg/mL (IQR, 7.4-34.9); and NIHSS score > 15, 21.0 pg/mL (IQR, 9.3-40.4) (P = 0.01). Compared with AIS, patients with TIA had lower sNfL levels [9.0 pg/mL (95% confidence interval, 4.0-19.0) vs. 16.0 pg/mL (95% confidence interval, 7.3-34.4), P < 0.001], also after adjusting for age and NIHSS score (P = 0.006). Among patients with AIS, infarct size on admission MR-DWI was not associated with sNfL, either in univariate analysis (P = 0.15) or after adjusting for age and NIHSS score on admission (P = 0.56). Functional outcome 3 months after stroke was not associated with sNfL after adjusting for established predictors.

CONCLUSIONS

In conclusion, among patients admitted within 24 h of AIS or TIA onset, admission sNfL levels were associated with clinical severity on admission and TIA diagnosis, but not with infarct size on MR-DWI acquired on admission or functional outcome at 3 months.

Serum Neurofilament Light Chain Levels in the Intensive Care Unit: Comparison between Severely Ill Patients with and without Coronavirus Disease 2019

There is emerging evidence for multifarious neurological manifestations of coronavirus disease 2019 (COVID-19), but little is known regarding whether they reflect structural damage to the nervous system. Serum neurofilament light chain (sNfL) is a specific biomarker of neuronal injury. We measured sNfL concentrations of 29 critically ill COVID-19 patients, 10 critically ill non-COVID-19 patients, and 259 healthy controls. After adjusting for neurological comorbidities and age, sNfL concentrations were higher in patients with COVID-19 versus both comparator groups. Higher sNfL levels were associated with unfavorable short-term outcome, indicating that neuronal injury is common and pronounced in critically ill patients. ANN NEUROL 2021;89:610-616.

Intravenous Thrombolysis in Patients with Stroke Taking Rivaroxaban Using Drug Specific Plasma Levels: Experience with a Standard Operation Procedure in Clinical Practice

Background and Purpose

Standard operating procedures (SOP) incorporating plasma levels of rivaroxaban might be helpful in selecting patients with acute ischemic stroke taking rivaroxaban suitable for IVthrombolysis (IVT) or endovascular treatment (EVT).

Methods

This was a single-center explorative analysis using data from the Novel-Oral-Anticoagulants-in-Stroke-Patients-registry (clinicaltrials.gov:NCT02353585) including acute stroke patients taking rivaroxaban (September 2012 to November 2016). The SOP included recommendation, consideration, and avoidance of IVT if rivaroxaban plasma levels were <20 ng/mL, 20‒100 ng/mL, and >100 ng/mL, respectively, measured with a calibrated anti-factor Xa assay. Patients with intracranial artery occlusion were recommended IVT+EVT or EVT alone if plasma levels were ≤100 ng/mL or >100 ng/mL, respectively. We evaluated the frequency of IVT/EVT, door-to-needle-time (DNT), and symptomatic intracranial or major extracranial hemorrhage.

Results

Among 114 acute stroke patients taking rivaroxaban, 68 were otherwise eligible for IVT/EVT of whom 63 had plasma levels measured (median age 81 years, median baseline National Institutes of Health Stroke Scale 6). Median rivaroxaban plasma level was 96 ng/mL (inter quartile range [IQR] 18‒259 ng/mL) and time since last intake 11 hours (IQR 4.5‒18.5 hours). Twenty-two patients (35%) received IVT/EVT (IVT n=15, IVT+EVT n=3, EVT n=4) based on SOP. Median DNT was 37 (IQR 30‒60) minutes. None of the 31 patients with plasma levels >100 ng/mL received IVT. Among 14 patients with plasma levels ≤100 ng/mL, the main reason to withhold IVT was minor stroke (n=10). No symptomatic intracranial or major extracranial bleeding occurred after treatment.

Conclusions

Determination of rivaroxaban plasma levels enabled IVT or EVT in one-third of patients taking rivaroxaban who would otherwise be ineligible for acute treatment. The absence of major bleeding in our pilot series justifies future studies of this approach.

Serum Neurofilament Light Chain Levels Are Associated with Clinical Characteristics and Outcome in Patients with Cervical Artery Dissection

BACKGROUND

Serum neurofilament light chain (sNfL) levels represent a promising marker of neuroaxonal injury. They are elevated in several neurological conditions, but their importance in cerebrovascular diseases remains unclear. In a proof of concept study, we compared sNfL levels with clinical characteristics and outcome in patients with cervical artery dissection (CeAD).

METHODS

A total of 49 non-traumatic CeAD patients were included. sNfL levels were measured by high-sensitivity electrochemiluminescence immunoassay. Levels were compared with regard to (i) type of presenting symptoms (local symptoms only (n = 8), transient ischemic attack (TIA; n = 10) or ischemic stroke (n = 31)), (ii) stroke severity quantified by National Institute of Health Stroke Scale (NIHSS), (iii) time interval between onset of symptoms and blood sampling and (iv) 3-month outcome as measured by the modified Rankin Scale score. Analyses were performed using univariate and multivariate linear and ordinal regression models.

RESULTS

CeAD patients presenting with stroke had significantly higher sNfL levels (median 108.9 pg/ml, interquartile range (37.8-427.7)) than patients with TIA (16.4 pg/ml (8.7-36.3), p = 0.002) or local symptoms (23.4 pg/ml (17.8-30.8), p = 0.0007). Among stroke patients, sNfL levels were positively associated with both NIHSS (p = 0.0002) and time between stroke onset and serum sampling (p = 1.9 × 10-6). Higher sNfL levels were associated with unfavorable outcome at 3 months (OR 4.67, 95% CI 1.69-12.95, p = 0.003). However, this association lost significance after adjustment for NIHSS. The highest sNfL level was observed in a TIA patient who had ischemic stroke 1 day after serum sampling for sNfL measurement.

CONCLUSION

sNfL levels were increased in CeAD patients presenting with stroke, correlated with clinical severity and were influenced by the time point of blood sampling. The prognostic meaning of sNfL in CeAD deserves further testing.

Prognostic performance of blood neurofilament light chain protein in hospitalized COVID-19 patients without major central nervous system manifestations: an individual participant data meta-analysis

BACKGROUND AND AIMS

To investigate the prognostic value of blood neurofilament light chain protein (NfL) levels in the acute phase of coronavirus disease 2019 (COVID-19).

METHODS

We conducted an individual participant data (IPD) meta-analysis after screening on MEDLINE and Scopus to May 23rd 2022. We included studies with hospitalized adult COVID-19 patients without major COVID-19-associated central nervous system (CNS) manifestations and with a measurement of blood NfL in the acute phase as well as data regarding at least one clinical outcome including intensive care unit (ICU) admission, need of mechanical ventilation (MV) and death. We derived the age-adjusted measures NfL Z scores and conducted mixed-effects modelling to test associations between NfL Z scores and other variables, encompassing clinical outcomes. Summary receiver operating characteristic curves (SROCs) were used to calculate the area under the curve (AUC) for blood NfL.

RESULTS

We identified 382 records, of which 7 studies were included with a total of 669 hospitalized COVID-19 cases (mean age 66.2 ± 15.0 years, 68.1% males). Median NfL Z score at admission was elevated compared to the age-corrected reference population (2.37, IQR: 1.13-3.06, referring to 99th percentile in healthy controls). NfL Z scores were significantly associated with disease duration and severity. Higher NfL Z scores were associated with a higher likelihood of ICU admission, need of MV, and death. SROCs revealed AUCs of 0.74, 0.80 and 0.71 for mortality, need of MV and ICU admission, respectively.

CONCLUSIONS

Blood NfL levels were elevated in the acute phase of COVID-19 patients without major CNS manifestations and associated with clinical severity and poor outcome. The marker might ameliorate the performance of prognostic multivariable algorithms in COVID-19.

Small vessel disease is associated with an unfavourable outcome in stroke patients on oral anticoagulation

Introduction

Cerebral small vessel disease is an important cause for both ischaemic stroke and intracranial haemorrhage. To date, knowledge on the impact of small vessel disease on the clinical course in stroke patients treated with oral anticoagulation for atrial fibrillation is limited.

Patients and Methods

Registry-based prospective observational study of 320 patients (aged 78.2 ± 9.2 years) treated with anticoagulation following atrial fibrillation stroke. Patients underwent standardised magnetic-resonance-imaging assessing measures of small vessel disease, including cerebral microbleeds and white matter hyperintensities. Median follow-up was 754 (interquartile range = [708-828]) days. Using adjusted logistic and Cox regression, we assessed the association of imaging measures with clinical outcome including recurrent ischaemic stroke, intracranial haemorrhage and death and assessed disability (modified Rankin Scale).

Results

Overall, recurrent ischaemic stroke was more common than intracranial haemorrhage (22 versus 8, respectively). Cerebral microbleeds were related to an increased risk of the composite endpoint (ischaemic stroke, intracranial haemorrhage, death: odds ratio (OR) 2.05, 95% confidence interval (CI) 1.27-3.31; P = 0.003), as were white matter hyperintensities (OR 2.00, 95%CI 1.23-3.27, P = 0.005). This was also true in time-to-event analysis (cerebral microbleeds: HR 2.31, 95%CI 1.39-3.52; P < 0.001; white matter hyperintensities: HR 1.99, 95%CI 1.20-3.17; P = 0.007). Both measures were associated with an increased risk for recurrent ischaemic stroke (cerebral microbleeds: HR 4.42, 95%CI 1.07-18.20; P = 0.04; white matter hyperintensities: HR 5.27, 95%CI 1.08-25.79, P = 0.04) and intracranial haemorrhage (cerebral microbleeds: HR 2.43, 95%CI 1.04-5.69; P = 0.04; white matter hyperintensities: HR 2.57, 95%CI 1.11-5.98, P = 0.03). Furthermore, confluent white matter hyperintensities were associated with increased disability (OR 4.03; 95%CI 2.16-7.52; P < 0.001) and mortality (HR 1.81, 95%CI 1.04-3.14, P = 0.04).

Discussion and conclusion

In atrial fibrillation stroke patients treated with oral anticoagulation, small vessel disease is associated with an unfavourable outcome. The presence of microbleeds indicated a risk higher for recurrent ischaemic stroke than for intracranial haemorrhage.

Oral Anticoagulants in Atrial Fibrillation Patients With Recent Stroke Who Are Dependent on the Daily Help of Others

BACKGROUND AND PURPOSE

Data on the effectiveness and safety of direct oral anticoagulants (DOACs) versus vitamin K antagonists (VKAs) in patients with stroke attributable to atrial fibrillation (AF) who were dependent on the daily help of others at hospital discharge are scarce.

METHODS

Based on prospectively obtained data from the observational Novel-Oral-Anticoagulants-in-Ischemic-Stroke-Patients-longterm registry from Basel, Switzerland, we compared the occurrence of the primary outcome-the composite of recurrent ischemic stroke, major bleeding, and all-cause death-among consecutive patients with AF-stroke treated with either VKAs or DOACs between patients dependent (defined as modified Rankin Scale score, 3-5) and patients independent at discharge. We used simple, adjusted, and weighted Cox proportional hazards regression to account for potential confounders.

RESULTS

We analyzed 801 patients (median age 80 years, 46% female), of whom 391 (49%) were dependent at discharge and 680 (85%) received DOACs. Over a total follow-up of 1216 patient-years, DOAC- compared to VKA-treated patients had a lower hazard for the composite outcome (hazard ratio [HR], 0.58 [95% CI, 0.42-0.81]), as did independent compared to dependent patients (HR, 0.54 [95% CI, 0.40-0.71]). There was no evidence that the effect of anticoagulant type (DOAC versus VKA) on the hazard for the composite outcome differed between dependent (HR_dependent, 0.68 [95% CI, 0.45-1.01]) and independent patients (HR_independent, 0.44 [95% CI, 0.26-0.75]) in the simple model (P_interaction=0.212). Adjusted (HR_dependent, 0.74 [95% CI, 0.49-1.11] and HR_independent, 0.51 [95% CI, 0.30-0.87]; P_interaction=0.284) and weighted models (HR_dependent, 0.79 [95% CI, 0.48-1.31] and HR_independent, 0.46 [95% CI, 0.26-0.81]; P_interaction=0.163) yielded concordant results. Secondary analyses focusing on the individual components of the composite outcome were consistent to the primary analyses.

CONCLUSIONS

The benefits of DOACs in patients with atrial fibrillation with a recent stroke were maintained among patients who were dependent on the help of others at discharge.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03826927.

Once versus twice daily direct oral anticoagulants in patients with recent stroke and atrial fibrillation

BACKGROUND

Data on the safety and effectiveness of once-daily (QD) versus twice-daily (BID) direct oral anticoagulants (DOAC) in comparison to vitamin K antagonists (VKA) and to one another in patients with atrial fibrillation (AF) and recent stroke are scarce.

PATIENTS AND METHODS

Based on prospectively obtained data from the observational registry Novel-Oral-Anticoagulants-in-Ischemic-Stroke-Patients(NOACISP)-LONGTERM (NCT03826927) from Basel, Switzerland, we compared the occurrence of the primary outcome - the composite of recurrent ischemic stroke, major bleeding, and all-cause death - among consecutive AF patients treated with either VKA, QD DOAC, or BID DOAC following a recent stroke using Cox proportional hazards regression including adjustment for potential confounders.

RESULTS

We analyzed 956 patients (median age 80 years, 46% female), of whom 128 received VKA (13.4%), 264 QD DOAC (27.6%), and 564 BID DOAC (59%). Over a total follow-up of 1596 patient-years, both QD DOAC and BID DOAC showed a lower hazard for the composite outcome compared to VKA (adjusted HR [95% CI] 0.69 [0.48, 1.01] and 0.66 [0.47, 0.91], respectively). Upon direct comparison, the hazard for the composite outcome did not differ between patients treated with QD versus BID DOAC (adjusted HR [95% CI] 0.94 [0.70, 1.26]). Secondary analyses focusing on the individual components of the composite outcome revealed no clear differences in the risk-benefit profile of QD versus BID DOAC.

DISCUSSION AND CONCLUSION

The overall benefit of DOAC over VKA seems to apply to both QD and BID DOAC in AF patients with a recent stroke, without clear evidence that one DOAC dosing regimen is more advantageous than the other.

The impact of competing stroke etiologies in patients with atrial fibrillation

BACKGROUND

Data on the impact of competing stroke etiologies in stroke patients with atrial fibrillation (AF) are scarce.

METHODS

We used prospectively obtained data from an observational registry (Novel-Oral-Anticoagulants-in-Ischemic-Stroke-Patients-(NOACISP)-LONGTERM) of consecutive AF-stroke patients treated with oral anticoagulants. We compared the frequency of (i) the composite outcome of recurrent ischemic stroke (IS), intracerebral hemorrhage (ICH) or all-cause death as well as (ii) recurrent IS alone among AF-stroke patients with versus without competing stroke etiologies according to the TOAST classification. We performed cox proportional hazards regression modeling adjusted for potential confounders. Furthermore, the etiology of recurrent IS was assessed.

RESULTS

Among 907 patients (median age 81, 45.6% female), 184 patients (20.3%) had competing etiologies, while 723 (79.7%) had cardioembolism as the only plausible etiology. During 1587 patient-years of follow-up, patients with additional large-artery atherosclerosis had higher rates of the composite outcome (adjusted HR [95% CI] 1.64 [1.11, 2.40], p = 0.017) and recurrent IS (aHR 2.96 [1.65, 5.35 ], p < 0.001), compared to patients with cardioembolism as the only plausible etiology. Overall 71 patients had recurrent IS (7.8%) of whom 26.7% had a different etiology than the index IS with large-artery-atherosclerosis (19.7%) being the most common non-cardioembolic cause.

CONCLUSION

In stroke patients with AF, causes other than cardioembolism as competing etiologies were common in index or recurrent IS. Concomitant presence of large-artery-atherosclerosis seems to indicate an increased risk for recurrences suggesting that stroke preventive means might be more effective if they also address competing stroke etiologies in AF-stroke patients.

CLINICAL TRIAL REGISTRATION

NCT03826927.

Impact of type of oral anticoagulants in patients with cerebral microbleeds after atrial fibrillation-related ischemic stroke or TIA: Results of the NOACISP-LONGTERM registry

Background

Cerebral microbleeds (CMBs) may have a differential impact on clinical outcome in stroke patients with atrial fibrillation (AF) treated with different types of oral anticoagulation (OAC).

Methods

Observational single-center study on AF-stroke-patients treated with OAC. Magnetic-resonance-imaging was performed to assess CMBs. Outcome measures consisted of recurrent ischemic stroke (IS), intracranial hemorrhage (ICH), death, and their combined analysis. Functional disability was assessed by mRS. Using adjusted logistic regression and Cox proportional-hazards models, we assessed the association of the presence of CMBs and OAC type (vitamin K antagonists [VKAs] vs. direct oral anticoagulants [DOACs]) with clinical outcome.

Results

Of 310 AF-stroke patients treated with OAC [DOACs: n = 234 (75%); VKAs: n = 76 (25%)], CMBs were present in 86 (28%) patients; of these, 66 (77%) received DOACs. In both groups, CMBs were associated with an increased risk for the composite outcome: VKAs: HR 3.654 [1.614; 8.277]; p = 0.002; DOACs: HR 2.230 [1.233; 4.034]; p = 0.008. Patients with CMBs had ~50% higher absolute rates of the composite outcome compared to the overall cohort, with a comparable ratio between treatment groups [VKAs 13/20(65%) vs. DOACs 19/66(29%); p &lt; 0.01]. The VKA-group had a 2-fold higher IS [VKAs:4 (20%) vs. DOACs:6 (9%); p = 0.35] and a 10-fold higher ICH rate [VKAs: 3 (15%) vs. DOACs: 1 (1.5%); p = 0.038]. No significant interaction was observed between type of OAC and presence of CMBs. DOAC-patients showed a significantly better functional outcome (OR 0.40 [0.17; 0.94]; p = 0.04).

Conclusions

In AF-stroke patients treated with OAC, the presence of CMBs was associated with an unfavorable composite outcome for both VKAs and DOACs, with a higher risk for recurrent IS than for ICH. Strokes were numerically higher under VKAs and increased in the presence of CMBs.

Clinical trial registration

http://www.clinicaltrials.gov, Unique identifier: NCT03826927.

Therapeutically induced EEG burst-suppression pattern to treat refractory status epilepticus—what is the evidence?

Current guidelines advocate to treat refractory status epilepticus (RSE) with continuously administered anesthetics to induce an artificial coma if first- and second-line antiseizure drugs have failed to stop seizure activity. A common surrogate for monitoring the depth of the artificial coma is the appearance of a burst-suppression pattern (BS) in the EEG. This review summarizes the current knowledge on the origin and neurophysiology of the BS phenomenon as well as the evidence from the literature for the presumed benefit of BS as therapy in adult patients with RSE.

Global Cortical Atrophy Is Associated with an Unfavorable Outcome in Stroke Patients on Oral Anticoagulation

INTRODUCTION

Measures of cerebral small vessel disease (cSVD), such as white matter hyperintensities (WMH) and cerebral microbleeds (CMB), are associated with an unfavorable clinical course in stroke patients on oral anticoagulation (OAC) for atrial fibrillation (AF). Here, we investigated whether similar findings can be observed for global cortical atrophy (GCA).

METHODS

Registry-based prospective observational study of 320 patients treated with OAC following AF stroke. Patients underwent magnetic resonance imaging (MRI) allowing assessment of GCA. Using the simplified visual Pasquier scale, the severity of GCA was categorized as follows: 0: no atrophy, 1: mild atrophy; 2: moderate atrophy, and 3: severe atrophy. Using adjusted logistic and Cox regression analysis, we investigated the association of GCA using a composite outcome measure, comprising: (i) recurrent acute ischemic stroke (IS); (ii) intracranial hemorrhage (ICH); and (iii) death.

RESULTS

In our time to event analysis after adjusting for potential confounders (i.e., WMH, CMB, age, sex, diabetes, arterial hypertension, coronary heart disease, hyperlipidemia, and antiplatelet use), GCA was associated with an increased risk for the composite outcome in all three degrees of atrophy (grade 1: aHR 3.95, 95% CI 1.34-11.63, p = 0.013; grade 2: aHR 3.89, 95% CI 1.23-12.30, p = 0.021; grade 3: aHR 4.16, 95% CI 1.17-14.84, p = 0.028).

CONCLUSION

GCA was associated with our composite outcome also after adjusting for other cSVD markers (i.e., CMB, WMH) and age, indicating that GCA may potentially serve as a prognostic marker for stroke patients with atrial fibrillation on oral anticoagulation.

Differences Between Anticoagulated Patients With Ischemic Stroke Versus Intracerebral Hemorrhage

Background Data on the relative contribution of clinical and neuroimaging risk factors to acute ischemic stroke (AIS) versus intracerebral hemorrhage (ICH) occurring on oral anticoagulant treatment are scarce. Methods and Results Cross-sectional study was done on consecutive oral anticoagulant-treated patients presenting with AIS, transient ischemic attack (TIA), or ICH from the prospective observational NOACISP (Novel-Oral-Anticoagulants-In-Stroke-Patients)-Acute registry. We compared clinical and neuroimaging characteristics (small vessel disease markers and atherosclerosis) in ICH versus AIS/TIA (reference) using logistic regression. Among 734 patients presenting with stroke on oral anticoagulant treatment (404 [55%] direct oral anticoagulants, 330 [45%] vitamin K antagonists), 605 patients (82%) had AIS/TIA and 129 (18%) had ICH. Prior AIS/TIA, coronary artery disease, dyslipidemia, and worse renal function were associated with AIS/TIA (adjusted odds ratio [aOR] [95% CI] 0.51 [0.32-0.82], 0.48 [0.26-0.86], 0.55 [0.34-0.89], and 0.82 [0.75-0.90] per 10 mL/min). Prior ICH, older age, higher admission blood pressure, and statin treatment were associated with ICH (aOR [95% CI] 6.33 [2.87-14.04], 1.37 [1.04-1.81] per 10 years, 1.19 [1.10-1.29] per 10 mm Hg, and 1.81 [1.09-3.03]). Cerebral microbleeds and moderate-to-severe white matter hyperintensities contributed more to ICH (aOR [95% CI] 2.77 [1.34-6.18], and 2.62 [1.28-5.63]). Aortic arch, common and internal carotid artery atherosclerosis, and internal carotid artery stenosis ≥50% contributed more to AIS/TIA (aOR [95% CI] 0.54 [0.31-0.90], 0.29 [0.05-0.97], 0.48 [0.30-0.76], and 0.32 [0.13-0.67]). Conclusions In patients presenting with stroke on oral anticoagulant, AIS/TIA was 5 times more common than ICH. A high atherosclerotic burden (indicated by cardiovascular comorbidities and extracranial atherosclerosis) and prior AIS/TIA contributed more to AIS/TIA, while small vessel disease markers and prior ICH were stronger determinants for ICH. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02353585.

Efficacy and Tolerability of Intranasal Midazolam Administration for Antiseizure Treatment in Adults: A Systematic Review

OBJECTIVE

The objective of this study was to assess the efficacy and tolerability of intranasal midazolam (in-MDZ) administration for antiseizure treatment in adults.

METHODS

Embase and Medline literature databases were searched. We included randomized trials and cohort studies (excluding case series) of adult patients (≥ 18 years of age) examining in-MDZ administration for epilepsy, epileptic seizures, or status epilepticus published in English between 1985 and 2022. Studies were screened for eligibility based on predefined criteria. The primary outcome was the efficacy of in-MDZ administration, and the secondary outcome was its tolerability. Extracted data included study design, patient characteristics, intervention details, and outcomes. Risk of bias was assessed using the Cochrane Risk of Bias Tool.

RESULTS

A total of 12 studies with 929 individuals treated with in-MDZ were included. Most studies were retrospective, with their number increasing over time. Administered in-MDZ doses ranged from 2.5 to 20 mg per single dose. The mean proportion of successful seizure termination after first in-MDZ administration was 72.7% (standard deviation [SD] 18%), and the proportion of seizure recurrence or persistent seizures ranged from 61 to 75%. Most frequent adverse reactions to in-MDZ were dizziness (mean 23.5% [SD 38.6%]), confusion (one study; 17.4%), local irritation (mean 16.6% [SD 9.6%]), and sedation (mean 12.7% [SD 9.7%]).

CONCLUSIONS

Administration of in-MDZ seems promising for the treatment of prolonged epileptic seizures and seizure clusters in adults. Limited evidence suggests that intranasal administration is safe. Further research is warranted because of the heterogeneity of cohorts, the variation in dosages, and the lack of uniformity in defining successful seizure termination.