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We investigate the scaling behavior of the magnetic dynamic order parameter Q in the vicinity of the dynamic phase transition (DPT) in the presence of temporal field sequences H(t) that are periodic with period P but lack half-wave antisymmetry. We verify by means of mean-field calculations that the scaling of Q is preserved in the vicinity of the second-order phase transition if one defines a suitable generalized conjugate field H^{*} that reestablishes the proper time-reversal symmetry. For the purpose of our quantitative data analysis, we employ the dynamic equivalent of the Arrott-Noakes equation of state, which allows for a simultaneous scaling analysis of the period P and the conjugate-field H^{*} dependence of Q. By doing so, we demonstrate that both the scaling behavior and universality are preserved, even if the dynamics is driven by a more general applied field sequence that lacks antisymmetry.
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INTRODUCTION: Seizures are a common complication of subarachnoid hemorrhage (SAH) in both acute and late stages: 10-20 % acute symptomatic seizures, 12-25 % epilepsy rate at five years. Our aim was to identify early electroencephalogram (EEG) and computed tomography (CT) findings that could predict long-term epilepsy after SAH. MATERIAL AND METHODS: This is a multicenter, retrospective, longitudinal study of adult patients with aneurysmal SAH admitted to two tertiary care hospitals between January 2011 to December 2022. Routine 30-minute EEG recording was performed in all subjects during admission period. Exclusion criteria were the presence of prior structural brain lesions and/or known epilepsy. We documented the presence of SAH-related cortical involvement in brain CT and focal electrographic abnormalities (epileptiform and non-epileptiform). Post-SAH epilepsy was defined as the occurrence of remote unprovoked seizures ≥ 7 days from the bleeding. RESULTS: We included 278 patients with a median follow-up of 2.4 years. The mean age was 57 (+/-12) years, 188 (68 %) were female and 49 (17.6 %) developed epilepsy with a median latency of 174 days (IQR 49-479). Cortical brain lesions were present in 189 (68 %) and focal EEG abnormalities were detected in 158 patients (39 epileptiform discharges, 119 non-epileptiform abnormalities). The median delay to the first EEG recording was 6 days (IQR 2-12). Multiple Cox regression analysis showed higher risk of long-term epilepsy in those patients with CT cortical involvement (HR 2.6 [1.3-5.2], p 0.009), EEG focal non-epileptiform abnormalities (HR 3.7 [1.6-8.2], p 0.002) and epileptiform discharges (HR 6.7 [2.8-15.8], p < 0.001). Concomitant use of anesthetics and/or antiseizure medication during EEG recording had no influence over its predictive capacity. ROC-curve analysis of the model showed good predictive capability at 5 years (AUC 0.80, 95 %CI 0.74-0.87). CONCLUSIONS: Focal electrographic abnormalities (both epileptiform and non-epileptiform abnormalities) and cortical involvement in neuroimaging predict the development of long-term epilepsy. In-patient EEG and CT findings could allow an early risk stratification and facilitate a personalized follow-up and management of SAH patients.
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Eletroencefalografia , Epilepsia , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/fisiopatologia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Longitudinais , Estudos Retrospectivos , Idoso , Epilepsia/etiologia , Epilepsia/diagnóstico , Epilepsia/diagnóstico por imagem , Epilepsia/fisiopatologia , Adulto , Tomografia Computadorizada por Raios X , Neuroimagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologiaRESUMO
The plasma membrane and the underlying skeleton form a protective barrier for eukaryotic cells. The molecules forming this complex composite material constantly rearrange under mechanical stress to confer this protective capacity. One of those molecules, spectrin, is ubiquitous in the membrane skeleton and primarily located proximal to the inner leaflet of the plasma membrane and engages in protein-lipid interactions via a set of membrane-anchoring domains. Spectrin is linked by short actin filaments and its conformation varies in different types of cells. In this work, we developed a generalized network model for the membrane skeleton integrated with myosin contractility and membrane mechanics to investigate the response of the spectrin meshwork to mechanical loading. We observed that the force generated by membrane bending is important to maintain a smooth skeletal structure. This suggests that the membrane is not just supported by the skeleton, but has an active contribution to the stability of the cell structure. We found that spectrin and myosin turnover are necessary for the transition between stress and rest states in the skeleton. Our model reveals that the actin-spectrin meshwork dynamics are balanced by the membrane forces with area constraint and volume restriction promoting the stability of the membrane skeleton. Furthermore, we showed that cell attachment to the substrate promotes shape stabilization. Thus, our proposed model gives insight into the shared mechanisms of the membrane skeleton associated with myosin and membrane that can be tested in different types of cells.
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AIM: Patients whose epilepsy begins with seizures with unknown etiology in old age have been studied to a limited extent. The aim is to clinically characterise these patients, and predict their risk of developing epilepsy in the long term. MATERIALS AND METHODS: This is a retrospective observational study of patients over 55 years old experiencing a first epileptic seizure with unknown etiology. The data were collected from their clinical history, including electroencephalogram (EEG) and brain magnetic resonance imaging (MRI) results. RESULTS: Eighty-seven patients (58.6% male; 71.5 ± 8.1 years) were included. The mean follow-up was 7.3 ± 4.9 years. The most common vascular risk factor was arterial hypertension (77%; n = 67). Focal seizures with altered consciousness were the most frequent type of seizure (44.8%; n = 39), followed by focal seizures evolving to bilateral tonic-clonic seizures (39.1%; n = 34). Brain MRI showed cortical atrophy (50%; n = 42) and signs of small-vessel vascular disease (SVVD) (67.8%; n = 57). Interictal epileptiform EEG abnormalities were observed in 43.7% (n = 38) of the patients, mostly with temporal localisations (94.7%; n = 36). 44.8% (n = 39) had mild cognitive impairment at baseline. Recurrence of seizures, which was observed in 49 patients (56.1%), occurred after a median of 12 months (interquartile range: 4.4-25.9). Finally, 71 patients (81.6%) developed epilepsy. CONCLUSION: The risk of epilepsy in the long term following a single seizure of unknown etiology in elderly patients is greater than 80%. Arterial hypertension and mild cognitive impairment at baseline are the most common clinical features. Cortical atrophy and the presence of SVVD are frequent in MRI, and routine EEGs do not usually show epileptiform alterations.
TITLE: Riesgo de epilepsia tras una primera crisis epiléptica de etiología desconocida en pacientes de edad avanzada.Objetivo. Los pacientes que comienzan con crisis de origen desconocido en la edad avanzada no están bien estudiados. El objetivo es caracterizar clínicamente a estos pacientes y predecir el riesgo de desarrollar epilepsia a largo plazo. Materiales y métodos. Es un estudio observacional retrospectivo en pacientes mayores de 55 años con una primera crisis epiléptica de causa desconocida. Se recogieron los datos desde la historia clínica, incluyendo electroencefalograma (EEG) y resonancia magnética (RM) cerebral. Resultados. Se incluyó a 87 pacientes (58,6% varones; 71,5 ± 8,1 años). El seguimiento medio fue de 7,3 ± 4,9 años. El factor de riesgo vascular más frecuente fue la hipertensión arterial (77%; n = 67). Las crisis focales con alteración de la conciencia fueron el tipo de crisis más frecuente (44,8%; n = 39), seguidas de las crisis focales con evolución a bilaterales tonicoclónicas (39,1%; n = 34). La RM cerebral mostró atrofia cortical (50%; n = 42) y signos de enfermedad vascular de pequeño vaso (EVPV) (67,8%; n = 57). Se observaron anomalías epileptiformes intercríticas en el EEG en un 43,7% (n = 38) de los pacientes, mayoritariamente con localización temporal (94,7%; n = 36). Hasta un 44,8% (n = 39) presentaba deterioro cognitivo leve basalmente. La recurrencia de crisis, observada en 49 pacientes (56,1%), sucedió con una mediana de 12 meses (rango intercuartílico: 4,4-25,9). Finalmente, 71 pacientes (81,6%) desarrollaron epilepsia. Conclusión. El riesgo de epilepsia a largo plazo tras una crisis única de etiología desconocida en pacientes de edad avanzada es superior al 80%. La hipertensión arterial y el deterioro cognitivo leve en el inicio son las características clínicas más frecuentes. En la RM, la atrofia cortical y la presencia de EVPV son frecuentes, y los EEG de rutina no suelen mostrar alteraciones epileptiformes.
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Eletroencefalografia , Epilepsia , Humanos , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Epilepsia/etiologia , Epilepsia/complicações , Imageamento por Ressonância Magnética , Fatores de Risco , Convulsões/etiologia , Convulsões/complicações , Idoso de 80 Anos ou mais , Medição de RiscoRESUMO
OBJECTIVE: To analyze the differences in clinical management during the epilepsy transition process from pediatric to adult care and to determine the quality of life and degree of satisfaction of patients and caregivers during the transition. METHODS: This is a longitudinal study including patients with epilepsy transferred from pediatric to adult epilepsy care between 2013 and 2017. Patients had a minimum follow-up of 3 years before the transition visit and at least 3 years consulting in the adults section. Clinical characteristics were retrieved from the medical chart. Quality of life and satisfaction questionnaires were administered by online access to patients and caregivers at the end of the adult follow-up period. RESULTS: 99 patients (50.5 % women, mean transition age 16.5 ± 1 years old) were included. Before the transition visit, 90 % of patients received a transition discussion and 88 % had a formal clinical report. In the pediatric period, patients were visited more frequently, had more EEGs and genetic studies, and were seen by the same neuropediatrician (P<0.05). In the adult period, patients underwent a larger number of prolonged video EEGs and were prescribed polytherapy more often (P<0.05). Quality of life remained steady during the entire transition, but satisfaction with the care received was significantly higher during the pediatric period. CONCLUSIONS: Significant differences were seen in epilepsy care during transition from pediatric to adult management, and this had an impact on the degree of satisfaction reported by patients and caregivers. Our results provide evidence of the potential value of development and early implementation of a protocolled transition program.
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Epilepsia , Transição para Assistência do Adulto , Adulto , Humanos , Criança , Feminino , Adolescente , Masculino , Estudos Longitudinais , Qualidade de Vida , Epilepsia/diagnóstico , Epilepsia/terapia , Inquéritos e QuestionáriosRESUMO
INTRODUCTION: This study aimed to determine whether the administration of antiepileptic drugs (AED) alters the likelihood of detecting epileptiform abnormalities in electroencephalographies (EEG) performed early after a first epileptic seizure. METHODS: We performed a retrospective, observational study including patients with a first seizure attended at our centre's emergency department between July 2014 and November 2019. We collected clinical data, as well as technical data on the acquisition and interpretation of the EEG performed within the first 72 hours after the seizure, and the factors related with seizure recurrence. RESULTS: We recruited 155 patients with a mean (SD) age of 48.6 (22.5) years; 61.3% were men. Regarding seizure type, 51% presented tonic-clonic seizures of unknown onset and 12% presented focal to bilateral tonic-clonic seizures. Thirty-nine patients (25.2%) received AED treatment before the EEG was performed: 33 received a non-benzodiazepine AED and 6 received a benzodiazepine. Epileptiform abnormalities were observed in 29.7% of patients. Previous administration of AEDs was not significantly associated with the probability of detecting interictal epileptiform abnormalities (P = .25) or with the risk of recurrence within 6 months (P = .63). CONCLUSIONS: Administration of AEDs before an early EEG following a first seizure does not decrease the likelihood of detecting epileptiform abnormalities. These findings suggest that starting AED treatment immediately in patients with a high risk of early recurrence does not imply a reduction in the diagnostic accuracy of the test.
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Epilepsias Parciais , Epilepsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticonvulsivantes/uso terapêutico , Eletroencefalografia , Epilepsias Parciais/diagnóstico , Epilepsia/diagnóstico , Epilepsia/tratamento farmacológico , Estudos Retrospectivos , Convulsões/tratamento farmacológico , Adulto , IdosoRESUMO
We explore the critical behavior of dynamic phase transitions in ultrathin uniaxial Co films. Our data demonstrate the occurrence of critical fluctuations, which define the critical regime, and in which we conduct a scaling analysis of the dynamic order parameter Q, utilizing a dynamic analog to the Arrott-Noakes equation of state. Our results show dynamic critical exponents that agree with the 2D Ising model as theoretically predicted. However, equilibrium critical exponents of our sample agree with the 3D Ising model. We argue that these differences between dynamic and thermodynamic behavior are due to fundamentally different length scales at which dimensional crossovers occur.
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We experimentally explore the magnetization dynamics of thin ferromagnetic Co films with uniaxial in-plane anisotropy near the dynamic phase transition (DPT) and, in particular, we study the temporal characteristics of anomalous metamagnetic fluctuations that occur in its vicinity, and for which no thermodynamic equivalent exists. For this purpose, we measure the real-time evolution of magnetization trajectories in the relevant dynamic phase space, conduct a Fourier analysis of these experimental results and compare it to a model, in which the fluctuating metamagnetic behavior occurs in a purely random manner, following individual state probability distributions. We find excellent quantitative agreement in between our experimental results and the random state model, clearly indicating that multiperiod time-correlations of magnetic states are not relevant in our DPT system, not even for the occurrence of the anomalous metamagnetic fluctuations that are nonetheless associated with nonperiodic magnetic state evolutions.
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Breast cancer (BC) is the leading cause of cancer in women, and has implications for sexual function (SF). In this study, we used an evidence map to identify, describe, and organise the current available evidence regarding SF in women with BC. We searched the MEDLINE, PsycINFO, and CINAHL databases for observational studies assessing SF in women with BC published in English, Spanish, Portuguese, and French between 2000 and 2021 (sample ≥ 50 women). Of the 64 included studies (13,257 women with BC), 58 were published since 2010. Women who were married, partnered, or in relationships represented 74.1% of the entire sample. Only a single study was conducted on women representing a sexual minority. We identified 22 assessment instruments and 40 sexual dysfunction (SdF) domains. The number of publications on SF in women with BC has increased in the last 10 years, but still remains low. Some groups of women are underrepresented, and some SdF domains are underdiagnosed, with the assessment instrument used affecting which domains are studied. Women with BC need to be better screened, as their quality of life (QoL) is affected by SdF.
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Neoplasias da Mama , Disfunções Sexuais Fisiológicas , Feminino , Humanos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/complicações , Qualidade de Vida , Disfunções Sexuais Fisiológicas/etiologia , Parceiros Sexuais , Estudos Observacionais como AssuntoRESUMO
OBJECTIVE: The COVID-19 pandemic has threatened to collapse hospital and ICU services, and it has affected the care programs for non-COVID patients. The objective was to develop a mathematical model designed to optimize predictions related to the need for hospitalization and ICU admission by COVID-19 patients. DESIGN: Prospective study. SETTING: Province of Granada (Spain). POPULATION: COVID-19 patients hospitalized, admitted to ICU, recovered and died from March 15 to September 22, 2020. STUDY VARIABLES: The number of patients infected with SARS-CoV-2 and hospitalized or admitted to ICU for COVID-19. RESULTS: The data reported by hospitals was used to develop a mathematical model that reflects the flow of the population among the different interest groups in relation to COVID-19. This tool allows to analyse different scenarios based on socio-health restriction measures, and to forecast the number of people infected, hospitalized and admitted to the ICU. CONCLUSIONS: The mathematical model is capable of providing predictions on the evolution of the COVID-19 sufficiently in advance as to anticipate the peaks of prevalence and hospital and ICU care demands, and also the appearance of periods in which the care for non-COVID patients could be intensified.
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COVID-19 , COVID-19/epidemiologia , Atenção à Saúde , Humanos , Unidades de Terapia Intensiva , Modelos Teóricos , Pandemias , Estudos Prospectivos , SARS-CoV-2RESUMO
BACKGROUND: Diagnosis of epileptic seizures, particularly regarding status epilepticus (SE), may be challenging in an emergency room setting. The aim of the study was to study the diagnostic yield of perfusion computed tomography (pCT) in patients with single epileptic seizures and SE. METHODS: We retrospectively reviewed the records of patients who followed an acute ischemic stroke pathway during a 9-month period and who were finally diagnosed with a single epileptic seizure or SE. Perfusion maps were visually analyzed for the presence of hyperperfusion and hypoperfusion. Clinical data, EEG patterns, and neuroimaging findings were compared. RESULTS: We included 47 patients: 20 (42.5%) with SE and 27 (57.5%) with single epileptic seizure. Of 18 patients who showed hyperperfusion on pCT, 12 were ultimately diagnosed with SE and eight had EEG findings compatible with an SE pattern. Focal hyperperfusion on pCT had a sensitivity of 60% (95% CI 36.4-80.2) and a specificity of 77.8% (95% CI 57.2-90.6) for predicting a final diagnosis of SE. The presence of cerebral cortical and thalamic hyperperfusion had a high specificity for predicting SE presence. Of note, 96% of patients without hyperperfusion on pCT did not show an SE pattern on early EEG. CONCLUSIONS: In acute settings, detection by visual analysis of focal cerebral cortical hyperperfusion on pCT in patients with epileptic seizures, especially if accompanied by the highly specific feature of thalamic hyperperfusion, is suggestive of a diagnosis of SE and requires clinical and EEG confirmation. The absence of focal hyperperfusion makes a diagnosis of SE unlikely.
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Epilepsia , AVC Isquêmico , Estado Epiléptico , Córtex Cerebral , Eletroencefalografia , Serviço Hospitalar de Emergência , Epilepsia/complicações , Humanos , Perfusão , Estudos Retrospectivos , Convulsões/diagnóstico por imagem , Estado Epiléptico/complicações , Estado Epiléptico/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodosRESUMO
BACKGROUND: Acute respiratory failure (ARF) has become one of the most prevalent serious pathologies encountered in the emergency medical service (EMS). In hospital settings, noninvasive ventilation (NIV) therapy prevents complications from more aggressive treatments for that condition. However, the scarce evidence on the benefits of NIV in prehospital EMS (i.e., during transport to the hospital) is inconclusive. OBJECTIVES: To determine whether the administration of NIV during prehospital EMS in cases of ARF reduces in-hospital mortality compared with starting NIV on arrival to in-patient EMS. METHODS: This is a multicentre, observational, prospective cohort study. We recruited a total of 317 patients from the Madrid region (Spain) who were prescribed NIV for their ARF using a nonprobabilistic consecutive sampling method. Analyses of the main outcome (in-hospital mortality) and secondary outcomes (length of hospital stay, readmissions, percentage of intensive care unit admissions, and cost-effectiveness) will include descriptive analyses of patients' characteristics, as well as bivariate and multivariate analyses and cost-effectiveness analysis. DISCUSSION: This study will provide data on NIV management in prehospital and in-patient EMS in patients with ARF. Results will contribute to the existing evidence on the benefits of NIV in the context of prehospital EMS while underlining the importance of a standardized formal training for physicians and nurses working in prehospital and in-patient EMSs. CONCLUSION: The VentilaMadrid study will provide valuable data on the clinical factors of patients receiving NIV in prehospital EMS. Further, were our hypothesis to be confirmed, our results would strongly suggest that the administration of NIV in prehospital EMS by medical and nursing profesionals formally trained in the technique reduces mortality and improves prognoses.
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Serviços Médicos de Emergência , Ventilação não Invasiva , Síndrome do Desconforto Respiratório , Estudos de Coortes , Serviços Médicos de Emergência/métodos , Humanos , Estudos Multicêntricos como Assunto , Ventilação não Invasiva/métodos , Estudos Observacionais como Assunto , Estudos Prospectivos , EspanhaRESUMO
OBJECTIVES: To evaluate the mammographic features in women with benign breast disease (BBD) and the risk of subsequent breast cancer according to their mammographic findings. METHODS: We analyzed data from a Spanish cohort of women screened from 1995 to 2015 and followed up until December 2017 (median follow-up, 5.9 years). We included 10,650 women who had both histologically confirmed BBD and mammographic findings. We evaluated proliferative and nonproliferative BBD subtypes, and their mammographic features: architectural distortion, asymmetries, calcifications, masses, and multiple findings. The adjusted hazard ratios (aHR) and 95% confidence intervals (95% CI) for breast cancer were estimated using a Cox proportional hazards model. We plotted the adjusted cumulative incidence curves. RESULTS: Calcifications were more frequent in proliferative disease with atypia (43.9%) than without atypia (36.8%) or nonproliferative disease (22.2%; p value < 0.05). Masses were more frequent in nonproliferative lesions (59.1%) than in proliferative lesions without atypia (35.1%) or with atypia (30.0%; p value < 0.05). Multiple findings and architectural distortion were more likely in proliferative disease (16.1% and 4.7%) than in nonproliferative disease (12.8% and 1.9%). Subsequent breast cancer occurred in 268 (2.5%) women. Compared with women who had masses, the highest risk of subsequent breast cancer was found in those with architectural distortions (aHR, 2.21; 95% CI, 1.16-4.22), followed by those with multiple findings (aHR, 1.89; 95% CI, 1.34-2.66), asymmetries (aHR, 1.66; 95% CI, 0.84-3.28), and calcifications (aHR, 1.60; 95% CI, 1.21-2.12). CONCLUSION: BBD subtypes showed distinct mammographic findings. The risk of subsequent breast cancer was high in those who have shown architectural distortion, multiple findings, asymmetries, and calcifications than in women with masses. KEY POINTS: ⢠The presence of mammographic findings in women attending breast cancer screening helps clinicians to assess women with benign breast disease (BBD). ⢠Calcifications were frequent in BBDs with atypia, which are the ones with a high breast cancer risk, while masses were common in low-risk BBDs. ⢠The excess risk of subsequent breast cancer in women with BBD was higher in those who showed architectural distortion compared to those with masses.
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Neoplasias da Mama , Doença da Mama Fibrocística , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Estudos de Coortes , Detecção Precoce de Câncer , Feminino , Humanos , Mamografia , Fatores de RiscoRESUMO
Brivaracetam is a newer antiseizure medication than levetiracetam. It has a more selective action on the synaptic vesicle glycoprotein 2A binding site, and it seems to provide a more favorable neuropsychiatric profile. The aim of this study was to assess the safety and tolerability of an overnight switch from levetiracetam to brivaracetam. This was a retrospective descriptive study including patients with epilepsy treated with levetiracetam, who switched due to inefficacy or previous adverse events (AEs). In total, forty-one patients were included (mean age 40.9 ± 17.8 years, women 48.8%). Focal epilepsy represented 75.6% (n = 31) of patients (structural cause [n = 25], unknown cause [n = 6]). Four patients had idiopathic generalized epilepsy, two had developmental and epileptic encephalopathy and four patients were unclassified. The reason to start brivaracetam was inefficacy in 53.7% (n = 22), AEs in 65.9% (25/27 neuropsychiatric) and both in 19.5% (n = 8). Brivaracetam-related AEs were reported in 24.4%. Neuropsychological AEs associated with the previous use of levetiracetam improved in 76% of patients. Treatment was discontinued in 19.5% patients. Patients' reported seizure frequency improved, worsened and remained stable in 26.8%, 12.2%, and 61.0% of the cases, respectively. An overnight switching to brivaracetam is safe and well tolerated. This treatment can improve levetiracetam-related neuropsychiatric AEs.