Cognitive phenotypes in patients with drug-resistant temporal lobe epilepsy: Relationships with cortisol and affectivity.

OBJECTIVE: Drug-resistant temporal lobe epilepsy (TLE) is a neurological disorder characterized by cognitive deficits. This study examined whether patients with TLE and different cognitive phenotypes differ in cortisol levels and affectivity while controlling for demographic and clinical variables. Methods: In this cross-sectional study, 79 adults with TLE underwent neuropsychological evaluation in which memory, language, attention/processing speed, executive function, and affectivity were assessed. Six saliva samples were collected in the afternoon to examine the ability of the hypothalamic-pituitary-adrenal (HPA) axis to descend according to the circadian rhythm (C1 to C6). The cortisol area under the curve concerning ground (AUCg) was computed to examine global cortisol secretion. RESULTS: Three cognitive phenotypes were identified: memory impairment, generalized impairment, and no impairment. The memory-impairment phenotype showed higher cortisol levels at C4, C5, and C6 than the other groups (p = 0.03, η2 = 0.06), higher cortisol AUCg than the generalized-impairment phenotype (p = 0.004, η2 = 0.14), and a significant reduction in positive affectivity after the evaluation (p = 0.026, η2 = 0.11). Higher cortisol AUCg and reductions in positive affectivity were significant predictors of the memory-impairment phenotype (p < 0.001; Cox and Snell R2 = 0.47). CONCLUSIONS: Patients with memory impairment had a slower decline in cortisol levels in the afternoon, which could be interpreted as an inability of the HPA axis to inhibit itself. Thus, chronic stress may influence hippocampus-dependent cognitive function more than other cognitive functions in patients with TLE.

Prospective study of cenobamate on cognition, affectivity, and quality of life in focal epilepsy.

OBJECTIVE: Cenobamate is a recently approved antiseizure medication that proved to be safe and effective in randomized controlled trials. However, little is known about its impact on some areas frequently affected by epilepsy. For this reason, we explored the effects of cenobamate on cognitive performance, as well as on negative affectivity and quality of life in a sample of patients with drug-resistant epilepsy. METHODS: Two prospective cohort studies were carried out. In Study 1, 32 patients (22 men and 10 women) underwent a baseline (T0) and a short-term (T1) neuropsychological assessment after 3 months of cenobamate administration. In Study 2, 22 patients (16 men and 6 women) from the T1 sample also underwent a baseline and a follow-up evaluation (T2) 6 months after T0. RESULTS: No significant differences were found in cognitive variables, negative affectivity, and quality of life either in Study 1 or Study 2. Similarly, based on the reliable change index, it was found that most patients showed no changes in these variables. SIGNIFICANCE: These results suggest that cenobamate is a safe antiseizure medication in terms of cognition, negative affectivity, or quality of life since no adverse events have been found after 3 and 6 months of treatment. PLAIN LANGUAGE SUMMARY: Cenobamate is a new antiseizure medication. In patients with epilepsy, cenobamate seems to not affect cognition, anxiety, depression, or quality of life.

Impact of antiseizure medication with a very long half-life on long term video-EEG monitoring in focal epilepsy.

PURPOSE: To assess the impact of antiseizure medications (ASMs) with a very long half-life on long term video-EEG monitoring (LTM) in people with focal epilepsy (FE). METHODS: In this retrospective cohort study, we searched our local database for people with FE who underwent ASM reduction during LTM at the University Hospital of 'La Fe', Valencia, from January 2013 to December 2019. Taking into account the half-life of the ASM, people with FE were divided into two groups: Group A contained individuals who were taking at least one ASM with a very long half-life at admission, and Group B consisted of those not taking very long half-life ASMs. Using multivariable analysis to control for important confounders, we compared the following outcomes between both groups: seizure rates per day, time to first seizure, and LTM duration. RESULTS: Three hundred seventy individuals were included in the study (154 in Group A and 216 in Group B). The median recorded seizure rates (1.3 seizures/day, range 0-15.3 vs.1.3 seizures/day, range 0-9.3, p-value=0.68), median time to the first seizure (24 h, range 2-119 vs. 24 h, range 2-100, p-value=0.92), and median LTM duration (4 days, range 2-5 vs. 4 days, range 2-5, p-value=0.94) were similar in both groups. Multivariable analysis did not reveal any significant differences in the three outcomes between the two groups (all p-values>0.05). CONCLUSION: ASMs with a very long half-life taken as co-medication do not significantly affect important LTM outcomes, including recorded seizure rates, time to the first seizure, or LTM duration. Therefore, in general, there is no need to discontinue ASMs with a very long half-life prior to LTM.

Impact of Polytherapy on Memory Functioning in Patients With Drug-Resistant Epilepsy: The Role of Attention and Executive Functions.

OBJECTIVE: The aim was to examine the effect of polytherapy (i.e., the number of administered anti-seizure medications (ASMs)) on memory, and whether the interaction between the number of ASMs and attentional/executive functioning affect presurgical memory functioning and postsurgical memory changes in patients with drug-resistant epilepsy. METHODS: Two studies were carried out. Study 1 consisted of a presurgical assessment of 125 adult patients, in which attention/executive function (EpiTrack screening tool) and memory were assessed (cross-sectional study). Of them, 72 patients underwent a second postsurgical evaluation, in which memory was assessed (Study 2). Patients were distributed into groups based on EpiTrack performance and number of ASMs. RESULTS: The interaction between the number of ASMs and the attentional/executive functioning significantly affected presurgical memory, with patients with impaired EpiTrack performance taking three-four ASMs having poorer scores than patients with intact EpiTrack performance taking three-four ASMs (for all, p < .0001). This interaction also affected postsurgical memory changes, with patients with impaired Epitrack performance taking three-four ASMs having higher postsurgical decline than those with intact Epitrack performance taking three-four ASMs (for all, p < .005). No differences were found in patients taking two ASMs. Furthermore, the number of ASMs was associated with presurgical memory performance and postsurgical memory changes only in patients with impaired EpiTrack performance (for all, p < .05). CONCLUSIONS: Our findings underline the utility of EpiTrack, together with the clinical information on the number of prescribed ASMs, to corroborate the impact of polytherapy on memory and to optimize the prediction of postsurgical memory changes.

Stress phenotypes in epilepsy: impact on cognitive functioning and quality of life.

Introduction: Drug-resistant epilepsy has been proposed as a chronic stress model. Stress can be measured in terms of chronicity (epilepsy duration) and intensity (comorbidities), with depression and anxiety among the most important comorbidities in epilepsy due to its prevalence and its relationship with cognitive functioning and quality of life. This study aims to establish phenotypes according to how patients face a stressful condition (epilepsy) and examine differences in cognition and quality of life depending on these phenotypes. We hypothesize that there will be an interrelationship between epilepsy duration and negative affectivity, and these variables will influence cognition and quality of life. Methods: 170 patients (82 men and 88 women) underwent a neuropsychological evaluation in which trait anxiety, depression, attention and executive function, verbal and visual memory, language, emotional recognition, and quality of life were assessed. Hierarchical clustering was performed using z-scores for three variables: trait anxiety; depression; and epilepsy duration. Results: Three clusters were found: vulnerable (high negative affectivity and short duration); resilient (moderate negative affectivity and long duration); and low-impact group (low negative affectivity and short duration). Results show that the vulnerable group had poorer cognitive functioning and quality of life than the other groups. Specifically, the vulnerable group had poorer scores than the low-impact group on verbal memory, visual confrontation naming, and quality of life (except seizure worry). Furthermore, resilient patients had better scores than the low-impact group on cognitive flexibility variables, but lower scores on some quality-of-life subscales (i.e., overall quality of life, emotional well-being, and energy). Finally, the vulnerable group had poorer scores than the resilient group in executive functioning, naming, and quality of life. Discussion: These results suggest that dealing with stress in patients with epilepsy is related to cognitive performance and quality of life. These findings underline the relevance of considering comorbidities in epilepsy and may be useful for detecting vulnerable or resilient profiles as risk or protective factors for cognitive and quality of life decline.

Real-world safety and effectiveness of cenobamate in patients with focal onset seizures: Outcomes from an Expanded Access Program.

OBJECTIVE: This study investigated early, real-world outcomes with cenobamate (CNB) in a large series of patients with highly drug-resistant epilepsy within a Spanish Expanded Access Program (EAP). METHOD: This was a multicenter, retrospective, observational study in 14 hospitals. Inclusion criteria were age ≥18 years, focal seizures, and EAP authorization. Data were sourced from patient clinical records. Primary effectiveness endpoints included reductions (100%, ≥90%, ≥75%, and ≥50%) or worsening in seizure frequency at 3-, 6-, and 12-month visits and at the last visit. Safety endpoints included rates of adverse events (AEs) and AEs leading to discontinuation. RESULTS: The study included 170 patients. At baseline, median epilepsy duration was 26 years and median number of seizures/month was 11.3. The median number of prior antiseizure medications (ASMs) and concomitant ASMs were 12 and 3, respectively. Mean CNB dosages/day were 176 mg, 200 mg, and 250 mg at 3, 6, and 12 months. Retention rates were 98.2%, 94.5%, and 87% at 3, 6, and 12 months. At last available visit, the rate of seizure freedom was 13.3%; ≥90%, ≥75%, and ≥50% responder rates were 27.9%, 45.5%, and 63%, respectively. There was a significant reduction in the number of seizures per month (mean: 44.6%; median: 66.7%) between baseline and the last visit (P < 0.001). Responses were maintained regardless of the number of prior or concomitant ASMs. The number of concomitant ASMs was reduced in 44.7% of patients. The cumulative percentage of patients with AEs and AEs leading to discontinuation were 68.2% and 3.5% at 3 months, 74.1% and 4.1% at 6 months, and 74.1% and 4.1% at 12 months. The most frequent AEs were somnolence and dizziness. SIGNIFICANCE: In this highly refractory population, CNB showed a high response regardless of prior and concomitant ASMs. AEs were frequent but mostly mild-to-moderate, and few led to discontinuation.

The relationship between memory and quality of life is mediated by trait anxiety in patients with temporal lobe epilepsy.

PURPOSE: Memory deficits are very frequent in patients with drug-resistant epilepsy, but they predict a small proportion of variance of their quality of life (QOL) in previous studies, possibly due to the lack of consideration of mediating factors of this relationship. This study aimed to examine whether trait anxiety mediates the relationship between memory and QOL in this population, controlling the influence of demographic and seizure-related factors. METHODS: In this cross-sectional study, 119 adults with drug-resistant temporal lobe epilepsy (TLE) underwent a neuropsychological evaluation, in which memory, anxiety, and QOL were assessed. RESULTS: In the total sample, better delayed memory had an effect on better QOL indirectly through lower trait anxiety (B = 0.13, SE = 0.06, p = 0.04, abcs = 0.13; κ2 = 0.18; PMind = 0.76). Additionally, delayed memory has not a direct association with QOL (B = 0.04, SE = 0.09, p = 0.64, Cohen's f 2 = 0.005; PMdir = 0.24), and the total effect of delayed memory on QOL tended to reach statistical significance (B = 0.17, SE = 0.10, p = 0.08). The proposed mediation model yielded excellent fit (CFI = 1.00, RMSEA = 0.0001, SRMR = 0.009, and χ2 (1) = 0.50, p = 0.48) and explained 38% of the variance of QOL. CONCLUSION: These findings suggest that trait anxiety is an important factor in understanding the relationship between memory and QOL in patients with TLE, considering the influence of demographic and seizure-related variables, and may have relevant implications for decision-making in this population.

Clinical utility of Epitrack for differentiating profiles and patterns of post-surgical change in memory and quality of life in patients with drug-resistant epilepsy.

PURPOSE: To assess whether performance in attention and executive functions evaluated with the Epitrack screening tool before surgery can differentiate memory and quality of life (QOL) profiles, and detect different post-surgical change patterns in these variables in patients with epilepsy. METHODS: This is a longitudinal study. Seventy-seven patients with drug-resistant epilepsy (mean age = 37.91) underwent a neuropsychological assessment before and one year after surgery. Epitrack, a screening tool that exclusively evaluates attention and executive functioning, was administered in the pre-surgical assessment, and verbal and visual memory and QOL were assessed before and after surgery. RESULTS: Patients with impaired Epitrack performance had poorer verbal and visual memory than those with intact Epitrack performance, regardless of the time point (for all, p < 0.0001). They also showed a post-surgical decline in immediate verbal recall (p = 0.04) and discriminability (p = 0.001). Patients with intact Epitrack performance did not exhibit this decline. Epitrack total score significantly contributed to 13 and 11% of the variance of post-surgical changes in immediate verbal recall and discriminability, respectively. Epitrack groups did not differ in QOL profiles or changes, but post-surgical immediate verbal recall improvements were related to post-surgical QOL improvements. CONCLUSION: Our findings underline the utility of Epitrack screening tool to detect different patterns of verbal and visual memory dysfunction, as well as to predict post-surgical verbal memory decline in patients with drug-resistant epilepsy. Patients with lower pre-surgical Epitrack scores appear to be at increased risk for post-surgical memory decline.

Outcome after resective epilepsy surgery in the elderly.

OBJECTIVE: The objective of this study was to compare complications, seizures, and neuropsychological outcomes after resective epilepsy surgery in patients ≥ 60 years of age who underwent operations to younger and matched controls. METHODS: Charts of 2243 patients were screened for operated patients in the authors' center between 2000 and 2015. Patients with available postsurgical follow-up data who were operated on at the age of 60 years or older and matched (by gender, histopathology, and side of surgery) controls who were between 20 and 40 years of age at the time of surgery were included. Outcomes regarding postoperative seizure control were scored according to the Engel classification and group comparisons were performed by using chi-square statistics. RESULTS: Data of 20 older patients were compared to those of 60 younger controls. Postoperative seizure control was favorable in the majority of the elderly patients (Engel classes I and II: 75% at 12 months, 65% at last follow-up), but the proportion of patients with favorable outcome tended to be larger in the control group (Engel classes I and II: 90% at 12 months, p = 0.092; 87% at last follow-up, p = 0.032, chi-square test). The surgical complication rate was higher in the elderly population (65% vs 27%, p = 0.002), but relevant persistent deficits occurred in 2 patients of each group only. Neuropsychological and behavioral assessments displayed considerable preoperative impairment and additional postoperative worsening, particularly of verbal skills, memory (p < 0.05), and mood in the elderly. CONCLUSIONS: The overall favorable postsurgical outcome regarding seizure control and the moderate risk of disabling persistent neurological deficits in elderly patients supports the view that advanced age should not be a barrier per se for resective epilepsy surgery and underscores the importance of an adequate presurgical evaluation and of referral of elderly patients to presurgical assessment.

COVID-19 prevalence and mortality in people with epilepsy: A nation-wide multicenter study.

BACKGROUND: To assess the prevalence, severity, and mortality of COVID-19 in people with epilepsy (PWE) and evaluate seizure control in PWE during and after COVID-19. METHODS: Retrospective, observational, multicenter study conducted in 14 hospitals. Medical records of randomly selected PWE followed at neurology outpatient clinics were reviewed. Proportion of PWE with a positive test for SARS-CoV-2 during 2020 was calculated. Risk factors associated with COVID-19 and its morbimortality were evaluated. RESULTS: 2751 PWE were included, mean age 48.8 years (18-99), 72.4% had focal epilepsy, and 35% were drug-refractory. COVID-19 prevalence in PWE was 5.53%, while in the Spanish population was 4.26%. Proportion of admissions to hospital, ICU, and deaths in PWE were 17.1%, 2%, and 4.61% of COVID-19 cases, while in Spanish population were 10.81%, 0.95%, and 2.57%, respectively. A severe form of COVID-19 occurred in 11.8%; dyslipidemia, institutionalization at long-term care facilities, intellectual disability, and older age were associated risk factors. Older age, hypertension, dyslipidemia, cardiac disease, and institutionalization were associated with mortality from COVID-19. Seizure control was stable in 90.1% of PWE during acute COVID-19, while 8.6% reported an increase in seizure frequency. During post-COVID-19 follow-up, 4.6% reported seizure control worsening. CONCLUSIONS: COVID-19 was moderately prevalent in PWE. One out of 5 patients required medical attention and 4.6% died due to COVID-19. Older age, dyslipidemia, institutionalization, and intellectual disability were significant risk factors associated with severe COVID-19. Seizure control remained stable during COVID-19 and throughout long-term follow-up in most PWE who contracted the infection.

Drug load and memory during intracarotid amobarbital procedure in epilepsy.

BACKGROUND: Anti-seizure medications (ASMs) have been related to poor cognitive function, but their relationship with intracarotid amobarbital procedure (IAP) results remains unclear. AIMS OF THE STUDY: To elucidate whether the number and drug load of ASMs are associated with memory scores of the IAP and the neuropsychological assessment. METHODS: Fifty-nine adult patients with drug-resistant epilepsy (mean age = 36.1, SD = 11.6) underwent bilateral IAP (with drawings and words as memory items) and a neuropsychological assessment to assess the risk of post-surgical memory decline. Total ASM drug load was calculated by summing the daily dose/defined daily dose ratio of every ASM of each patient. Pearson's correlations and hierarchical regressions were computed. RESULTS: Total IAP memory score was associated with total ASM drug load (r = -0.30, p = 0.02) and seizure frequency (r = -0.25, p = 0.05). After controlling clinical variables, total ASM drug load explained 16% of the variance of total IAP memory score. This relationship was especially prominent in patients with left hemisphere focus (r = -0.33, p = 0.04). The number of current ASMs was not related to IAP memory score (r = -0.16, p = 0.24). The number or drug load of ASMs were not related to neuropsychological assessment results (for all, p > 0.07). CONCLUSIONS: Our findings suggest that total drug load can be a confounding variable in the IAP memory performance that could explain, at least in part, the reverse asymmetries reported in different studies.

The number of anti-seizure medications mediates the relationship between cognitive performance and quality of life in temporal lobe epilepsy.

OBJECTIVES: To assess whether cognitive performance predicts quality of life (QOL) in patients with drug-resistant temporal lobe epilepsy (TLE), using the Epitrack cognitive screening tool, while considering the mediating role of the number of anti-seizure medications (ASMs) and controlling for seizure-related, social, and emotional factors. METHODS: Seventy-five adult patients with drug-resistant TLE (mean age = 39.76 years, SD = 11.66) underwent a presurgical neuropsychological assessment. MAIN OUTCOME MEASURES: Cognitive performance (Epitrack), depression (BDI-II), trait anxiety (STAI); and QOL (QOLIE-31) were assessed. RESULTS: Adjusting for seizure-related, social, and emotional factors, the Epitrack total score significantly contributed to QOL composite score, and energy and cognitive self-rating subscales. We found a significant indirect effect of the Epitrack total score on QOL composite score and seizure worry and social functioning subscales via the number of ASMs. CONCLUSION: Our findings underline the relevance of cognitive functioning on QOL and the clinical utility of Epitrack to track cognitive side effects of ASMs and, consequently, to predict and manage QOL in this population.

Epilepsy surgery beyond 50 years: Long-term seizure and cognitive outcomes.

INTRODUCTION: Surgery is a well-demonstrated effective treatment for patients with refractory epilepsy. However, there are scarce data about the efficacy in older patients. Endpoint was to evaluate the outcome of epilepsy surgery in pharmacorresistant patients operated in middle-late adulthood. METHODS: We conducted a retrospective observational study including patients who underwent a epilepsy surgery at age ≥ 50. Presurgical clinical data, type of surgery, and postsurgical seizure outcome and neurological complications, including neuropsychological assessment were analyzed. Minimum post-surgical follow-up was 1 year. RESULTS: We identified 38 patients (22 males, 17 females) out of 350 patients who underwent a resective surgery with curative intention in our Epilepsy Unit (12%). Median age at surgery was 56 years (50-69), with median epilepsy duration of 42 years (4-67). Neuroimaging showed focal epileptogenic lesions in 37 patients, mainly mesial temporal sclerosis (21). Presurgical neuropsychological evaluation was available in 38 patients: 35 had deficits, mostly in verbal or visual memory. Twenty-eight patients underwent standard temporal lobectomy with amygdalohippocampectomy, 7 lesionectomy and 4 lobectomy. Median follow-up was 4.46 years (1-9.75). A good outcome was achieved by 86.8% (28 Engel I; 5 Engel II); 5 patients were studied with SEEG, without any complications. None had postsurgical permanent neurological complications. From 22 patients with available post-surgical neuropsychological assessment, 16 scored lower than in pre-surgical one, mainly in memory domain. CONCLUSION: Surgical treatment of long-term refractory epilepsy in patients ≥50 years can be effective and safe. Post-surgical memory decline is a frequent side effect, but with a low impact in daily life.

Blood Pressure in Seizures and Epilepsy.

In this narrative review, we summarize the current knowledge of neurally mediated blood pressure (BP) control and discuss how recently described epilepsy- and seizure-related BP alterations may contribute to premature mortality and sudden unexpected death in epilepsy (SUDEP). Although people with epilepsy display disturbed interictal autonomic function with a shift toward predominant sympathetic activity, prevalence of arterial hypertension is similar in people with and without epilepsy. BP is transiently increased in association with most types of epileptic seizures but may also decrease in some, illustrating that seizure activity can cause both a decrease and increase of BP, probably because of stimulation or inhibition of distinct central autonomic function by epileptic activity that propagates into different neuronal networks of the central autonomic nervous system. The principal regulatory neural loop for short-term BP control is termed baroreflex, mainly involving peripheral sensors and brain stem nuclei. The baroreflex sensitivity (BRS, expressed as change of interbeat interval per change in BP) is intact after focal seizures, whereas BRS is markedly impaired in the early postictal period following generalized convulsive seizures (GCS), possibly due to metabolically mediated muscular hyperemia in skeletal muscles, a massive release of catecholamines and compromised brain stem function. Whilst most SUDEP cases are probably caused by a cardiorespiratory failure during the early postictal period following GCS, a profoundly disturbed BRS may allow a life-threatening drop of systemic BP in the aftermath of GCS, as recently reported in a patient as a plausible cause of SUDEP in a few patients.

Cortisol and trait anxiety as relevant factors involved in memory performance in people with drug-resistant epilepsy.

People with drug-resistant epilepsy are exposed to unpredictable and uncontrollable seizures, which can be considered as a chronic stress condition. Additionally, these patients present memory deficits and a high prevalence of depression and anxiety. Cortisol, the main stress hormone, has a modulatory role on memory in healthy individuals and patients with emotional disorders, but its role in memory and emotional processes remains unclear in people with epilepsy. This study analyzes the differences in cortisol levels in people with epilepsy with high and low memory performance, and the relationships among cortisol levels, epilepsy-related factors, memory, anxiety, and depression. Fifty-two adults with drug-resistant epilepsy underwent a neuropsychological evaluation, in which nine saliva samples were collected to analyze the ability of the hypothalamic-pituitary-adrenal axis to descend in accordance with the circadian rhythm. Cortisol area under the curve (AUC) was computed to study the global cortisol changes. Patients with low immediate and delayed memory performance and left-hemisphere focus showed higher cortisol levels. Additionally, patients with low memory scores had higher cortisol AUC, and therefore slower declining levels in the afternoon. Memory performance was negatively related to the cortisol AUC and trait anxiety, being both reliable predictors of memory performance, especially in patients with left-hemisphere focus. These results suggest that memory deficits in people with drug-resistant epilepsy may be influenced by exposure to cortisol derived from chronic stress. Additionally, trait anxiety could contribute to increasing the vulnerability to stress.

Quality of life in drug-resistant epilepsy: relationships with negative affectivity, memory, somatic symptoms and social support.

OBJECTIVE: To investigate the relative contribution of factors non-directly related to seizures such as negative affectivity, social support, somatic symptoms and memory performance on quality of life (QOL) in patients with drug-resistant epilepsy. METHODS: This is a cross-sectional study. Seventy patients with drug-resistant epilepsy were consecutively recruited from the inpatient Epilepsy Unit, Hospital Universitario y Politécnico La Fe, between April 2015 and October 2017. Medical history provided demographic characteristics of the patients (sex, age, and educational level), and clinical data (age at epilepsy onset, duration of epilepsy in years, frequency of seizures per month, type of seizures and number of AEDs). Pre-surgical assessment included diagnosis of the type of epilepsy and the lateralization of the epileptogenic area. All the patients underwent a neuropsychological assessment in which QOL (QOLIE-31), negative affectivity, social support, somatic symptoms, and memory were evaluated. RESULTS: Negative affectivity (including anxiety-trait and depression), social support, neurosensory symptoms, and long-term verbal memory were significantly related to QOL composite score (for all, p < .009), subscales of QOL showing different sensitivities to them. Even after controlling for negative affectivity, neurosensory symptoms and long-term verbal memory significantly contribute to QOL composite score (p = .0001). CONCLUSION: Results suggest that clinical management of patients with drug-resistant epilepsy should consider the treatment of verbal memory impairments at an early stage. Recognition of negative affectivity, poor social support and high somatic symptoms would also lead health professionals to develop different strategies to improve the QOL of patients with drug-resistant epilepsy.

Antiepileptic drug reduction and increased risk of stimulation-evoked focal to bilateral tonic-clonic seizure during cortical stimulation in patients with focal epilepsy.

INTRODUCTION: Stimulation-evoked focal to bilateral tonic-clonic seizure (FBTCS) can be a stressful and possibly harmful adverse event for patients during cortical stimulation (CS). We evaluated if drug load reduction of antiepileptic drugs (AEDs) during CS increases the risk of stimulation-evoked FBTCS. MATERIAL AND METHODS: In this retrospective cohort study, we searched our local database for patients with drug-resistant epilepsy who underwent invasive video-EEG monitoring and CS in the University Hospital la Fe Valencia from January 2006 to November 2016. The AED drug load was calculated with the defined daily dose. We applied a uni- and multivariate logistic regression model to estimate the risk of stimulation-evoked FBTCS and evaluate possible influencing factors. Furthermore, we compared patients whose AEDs were completely withdrawn with those whose AEDs were not. RESULTS: Fifty-eight patients met the inclusion criteria and were included in the analysis. Stimulating 3806 electrode contact pairs, 152 seizures were evoked in 28 patients (48.3%). Ten seizures (6.6%) in seven patients (12.1%) evolved to FBTCS. In the univariate and multivariate analysis, a 10% reduction in drug load was associated with an increase of the odds ratio (OR) of stimulation-evoked FBTCS by 1.9 (95%-CI 1.2, 4.0, p-value=0.04) and 1.9 (95%-CI 1.2, 4.6, p-value=0.04), respectively. In patients, whose AEDs were completely withdrawn the OR of FBTCS increased by 9.1 (95%CI 1.7, 69.9, p-value=0.01) compared with patients whose AEDs were not completely withdrawn. No other factor (implantation type, maximum stimulus intensity, number of stimulated contacts, history of FBTCS, age, gender, or epilepsy type) appears to have a significant effect on the risk of stimulation-evoked FBTCS. CONCLUSIONS: The overall risk of stimulation-evoked FBTCS during CS is relatively low. However, a stronger reduction and, especially, a complete withdrawal of AEDs are associated with an increased risk of stimulation-evoked FBTCS.

Memory encoding-related anterior hippocampal potentials are modulated by deep brain stimulation of the entorhinal area.

BACKGROUND: Deep brain stimulation (DBS) of the human entorhinal area using 50 Hz pulses has revealed conflicting results regarding memory performance. Moreover, its impact on memory-related hippocampal potentials has not yet been investigated. METHODS: We recorded data from seven epilepsy patients implanted with depth electrodes in the entorhinal cortex, hippocampus, amygdala, and parahippocampal cortex. Entorhinal DBS (bipolar, biphasic 50 Hz pulses, on- and off-cycles of 15 s) was applied with low amplitude (0.1 mA) to resemble physiologic conditions. During DBS on- and off-periods, patients learned noun-color associations that were later tested. RESULTS: During entorhinal DBS we observed more positive deflections of event-related potentials (ranging from 700 to 950 ms) in the anterior hippocampus for the on- vs. off-condition. We detected no effects in the amygdala, mid hippocampus and parahippocampal cortex. On the behavioral level, no differences in memory performance (item and source memory) were apparent in the on- vs. off-condition, neither across all trials nor across patients. DISCUSSION: Our findings indicate that entorhinal DBS with low amplitude has an impact on memory encoding-related potentials within the anterior hippocampus, but not on memory performance per se.

Recurrence risk of ictal asystole in epilepsy.

OBJECTIVE: To determine the recurrence risk of ictal asystole (IA) and its determining factors in people with epilepsy. METHODS: We performed a systematic review of published cases with IA in 3 databases and additionally searched our local database for patients with multiple seizures simultaneously recorded with ECG and EEG and at least one IA. IA recurrence risk was estimated by including all seizures without knowledge of the chronological order. Various clinical features were assessed by an individual patient data meta-analysis. A random mixed effect logistic regression model was applied to estimate the average recurrence risk of IA. Plausibility of the calculated IA recurrence risk was checked by analyzing the local dataset with available information in chronological order. RESULTS: Eighty patients with 182 IA in 537 seizures were included. Recurrence risk of IA amounted to 40% (95% confidence interval [CI] 32%-50%). None of the clinical factors (age, sex, type and duration of epilepsy, hemispheric lateralization, duration of IA per patient) appeared to have a significant effect on the short-term recurrence risk of IA. When considering the local dataset only, IA recurrence risk was estimated to 30% (95% CI 14%-53%). Information whether IA coincided with symptoms (i.e., syncope) or not was given in 60 patients: 100 out of 142 IAs were symptomatic. CONCLUSION: Our data suggest that in case of clinically suspected IA, the recording of 1 or 2 seizures is not sufficient to rule out IA. Furthermore, the high short-term recurrence risk favors aggressive treatment, including pacemaker implantation if seizure freedom cannot be achieved.

Impaired Baroreflex Sensitivity after Bilateral Convulsive Seizures in Patients with Focal Epilepsy.

BACKGROUND: Sudden unexpected death in epilepsy (SUDEP) is probably due to an autonomic failure in the early postictal phase after bilateral convulsive seizures (BCS) in the majority of cases. The baroreflex sensitivity (BRS) is an established and reliable biomarker of autonomic function and sudden cardiac death. OBJECTIVE: To investigate whether postictal BRS depends on seizure type. METHODS: Beat-to-beat systemic blood pressure and heart rate were continuously and non-invasively recorded with the ccNexfin® device in patients with focal epilepsy undergoing video-EEG monitoring. BRS was calculated using the sequence as well as the spectral method. A random mixed linear model was applied to analyze the influence of seizure type on BRS during three different time periods of 15-min length each (interictal, preictal, and postictal). In addition, the possible effects of other factors (hypertension, hemispheric lateralization of ictal activity, epilepsy type, body position, vigilance state) were explored. Data are given as median with interquartile range. RESULTS: A total of 26 seizures of 26 patients were analyzed. In BCS (n = 7), BRS significantly dropped from a preictal value of 15.0 ms/mm Hg (13.0-19.4) and an interictal value of 15.6 ms/mm Hg (12.0-20.4) to 3.1 ms/mm Hg (2.7-10.5) during the postictal period (p < 0.0001) according to the sequence method. This finding was replicated with the spectral method. In contrast, focal seizures (n = 19) did not lead to significant alterations of BRS in the postictal phase. CONCLUSION: Postictal BRS depends on the seizure type and is markedly impaired after BCS. The present study provides further evidence for a disturbed autonomic function following BCS. These findings might be related to cardiovascular failure in the context of SUDEP.