Post-stroke epilepsy. / Epilepsi oppstått etter hjerneslag.

Epilepsy as a result of stroke is currently the most rapidly increasing form of epilepsy. The risk of post-stroke epileptogenesis is higher after haemorrhagic stroke than after ischemic stroke. We provide here a brief clinical review of the topic to highlight the misinterpretation and undertreatment of focal epileptic seizures in stroke patients. Correct diagnosis and treatment are important because recurrent epileptic seizures can reduce quality of life and hinder rehabilitation.

Screening for depression in patients with epilepsy: What are the benefits for physicians and patients in the real-life setting.

OBJECTIVE: Screening for depression in people with epilepsy (PWE) is highly recommended in order to avoid underdiagnosis, misdiagnosis, or delayed diagnosis of this highly impacting comorbidity. Here we evaluated the impact of reporting and suggesting depression via the Beck Depression Inventory (BDI) on medical decision-making, and thereby the value of a depression screening for good medical practice. METHODS: Of 445 BDI data sets, PWE with scores indicating moderate (BDI 19-29) to severe depressive disorder (BDI >29) were extracted and clinical reports were retrospectively reviewed regarding decisions on antidepressants, anti-seizure medications (ASMs), and non-pharmaceutical interventions. RESULTS: Sixty-four PWE (14%; 56% female; mean age 39.7 years) showed elevated BDI scores, with 40 (63%) categorized as moderate depression and 24 (37%) as severe depression. Thirty-nine percent of PWE already had a pre-existing diagnosis of depression and 53% left the clinic with the diagnosis of depression, half of them with antidepressants. High depression scores were associated with any intervention in 53%, interventions with potentially mood affecting ASM in 19%, treatment with antidepressants in 11%, and non-pharmaceutical interventions in 41%. Non-pharmaceutical interventions were related to BDI scores. Changes of potentially mood-affecting ASMs were more frequent in PWE with moderate scores, and introduction of antidepressants appeared as a trend related to higher depression scores. SIGNIFICANCE: The finding of an only weak relation between high depression scores, diagnoses of depression, and treatment consequences questions the diagnosis and treatment pathway and the clinical value of the BDI screening in PWE. Prospective standard procedures need to be established for depression diagnosis and treatment including follow-up evaluations of the validity of the diagnosis and effectiveness of the decisions taken.

Young people diagnosed with psychogenic nonepileptic seizures (PNES) years ago - How are they now?

BACKGROUND: Up to 30% of patients referred to epilepsy centres for drug-resistant epilepsy turn out to have psychogenic nonepileptic seizures (PNES). Patients with PNES are a very heterogeneous population with large differences in regard to underlying causes, seizures severity, and impact on quality of life. There is limited knowledge regarding the long-term seizure prognosis of youth with PNES and its influential factors. METHODS: We have performed a retrospective study on adolescents diagnosed with PNES who were receiving inpatient care at our hospital for 2-4 weeks in the period of 2012-2020. They all attended psychoeducational courses to educate them about PNES, coping with the seizures, and possible contributors to seizure susceptibility. There were 258 patients who fulfilled the inclusion criteria. We contacted them by text messages, through which they received brief information about the study and an invitation to participate. There were 62 patients (24 %) who agreed and participated in structured telephone interviews. We excluded 10 patients due to concomitant epilepsy. The mean age of the remaining 52 participants was 20.9 years (16-28 years), and 45 (87 %) were women. RESULTS: After a mean of 4.7 years (2-9 years) since discharge from our hospital, 28 patients (54 %) had been free of seizures in the last 6 months. There were 16 patients (31 %) who had better situations in regard to seizures but were not completely seizure free, while 8 patients (15 %) were either unchanged (3 patients) or worse (5 patients). There were 39 patients (75 %) who had received conversation therapy, and 37 patients (71 %) had been treated by a psychologist or psychiatrist. There were 10 patients (19 %) who had dropped out of school or work, and the percentage increased with age. There were 42 patients (80 %) who perceived their health as good or very good. CONCLUSION: Patients had a relatively favourable seizure prognosis as 54% were free of seizures and 31% had a better seizure situation, at the time of this study. However, the fact that 19% had dropped out of school or work was worrying. Young age and satisfaction with treatment were associated with being employed or receiving education. Satisfaction with perceived treatment was significantly associated with personal experience of good health. This emphasizes the importance of early diagnosis, adapted interventional measures, and long-term follow-up by healthcare for young people with PNES.

Norwegian population-based study of effectiveness of vagus nerve stimulation in patients with developmental and epileptic encephalopathies.

OBJECTIVE: Evaluate the long-term efficacy of vagus nerve stimulation (VNS) in patients with developmental and epileptic encephalopathies (DEE) compared with epilepsy patients without intellectual disability (ID). METHODS: Long-term outcomes from a Norwegian VNS quality registry are reported in 105 patients with DEEs (Lennox-Gastaut syndrome [LGS] n = 62; Dravet n = 16; Rett n = 9; other syndromes n = 18) were compared with 212 epilepsy patients without ID, with median follow-up of 88 and 72 months, respectively. Total seizure reduction was evaluated at 6, 12, 24, 36, and 60 months. Effect on different seizure types was evaluated at baseline and last observation carried forward (LOCF). RESULTS: Median monthly seizure frequency at LOCF was reduced by 42.2% (p < 0.001) in patients with DEE and by 55.8% (p < 0.001) in patients without ID. In DEE patients, ≥50% seizure reduction at 6 and 24 months were 17.1% and 37.1%, respectively, and 33.5% and 48.6% for patients without ID. Seizure reduction ≥75% at 60 months occurred in 14.3% of DEE patients and 23.1% of patients without ID. Highest median reduction was for atonic seizures, most notably 64.6% for LGS patients. A better effect was seen at 2 years among DEE patients with unchanged medication compared with those with changed medication (54.5% vs. 35.6% responders, p = 0.078). More DEE patients were reported to have greater improvement in ictal or postictal severity (43.8% vs. 28.3%, p = 0.006) and alertness (62.9% vs. 31.6%, p < 0.001) than patients without ID. For both groups, use of the magnet reduced seizure severity. Hoarseness was the most common adverse effect in both groups. In addition, DEE patients were frequently reported to have sleep disturbance, general discomfort, or abdominal problems. SIGNIFICANCE: Our data indicate that VNS is very effective for atonic seizures. Patients without ID had best overall seizure reduction, however, patients with DEE had higher retention rates probably due to other positive effects. PLAIN LANGUAGE SUMMARY: DEE refers to a group of patients with severe epilepsy and intellectual disability. Many of these patients have restricted lifestyles with frequent seizures. VNS is a treatment option for patients who do not respond well to medicines, either because of insufficient effect or serious adverse effects. Our study shows that VNS is well tolerated in this patient group and leads to a reduction in all seizure types, most notably for seizures leading to fall. Many patients experience other positive effects like shorter and milder seizures, as well as improvement in alertness.

Variation in seizure risk increases from antiseizure medication withdrawal among patients with well-controlled epilepsy: A pooled analysis.

OBJECTIVE: Guidelines suggest considering antiseizure medication (ASM) discontinuation in seizure-free patients with epilepsy. Past work has poorly explored how discontinuation effects vary between patients. We evaluated (1) what factors modify the influence of discontinuation on seizure risk; and (2) the range of seizure risk increase due to discontinuation across low- versus high-risk patients. METHODS: We pooled three datasets including seizure-free patients who did and did not discontinue ASMs. We conducted time-to-first-seizure analyses. First, we evaluated what individual patient factors modified the relative effect of ASM discontinuation on seizure risk via interaction terms. Then, we assessed the distribution of 2-year risk increase as predicted by our adjusted logistic regressions. RESULTS: We included 1626 patients, of whom 678 (42%) planned to discontinue all ASMs. The mean predicted 2-year seizure risk was 43% [95% confidence interval (CI) 39%-46%] for discontinuation versus 21% (95% CI 19%-24%) for continuation. The mean 2-year absolute seizure risk increase was 21% (95% CI 18%-26%). No individual interaction term was significant after correcting for multiple comparisons. The median [interquartile range (IQR)] risk increase across patients was 19% (IQR 14%-24%; range 7%-37%). Results were unchanged when restricting analyses to only the two RCTs. SIGNIFICANCE: No single patient factor significantly modified the influence of discontinuation on seizure risk, although we captured how absolute risk increases change for patients that are at low versus high risk. Patients should likely continue ASMs if even a 7% 2-year increase in the chance of any more seizures would be too much and should likely discontinue ASMs if even a 37% risk increase would be too little. In between these extremes, individualized risk calculation and a careful understanding of patient preferences are critical. Future work will further develop a two-armed individualized seizure risk calculator and contextualize seizure risk thresholds below which to consider discontinuation. PLAIN LANGUAGE SUMMARY: Understanding how much antiseizure medications (ASMs) decrease seizure risk is an important part of determining which patients with epilepsy should be treated, especially for patients who have not had a seizure in a while. We found that there was a wide range in the amount that ASM discontinuation increases seizure risk-between 7% and 37%. We found that no single patient factor modified that amount. Understanding what a patient's seizure risk might be if they discontinued versus continued ASM treatment is critical to making informed decisions about whether the benefit of treatment outweighs the downsides.

Role of the glymphatic system and perivascular spaces as a potential biomarker for post-stroke epilepsy.

Stroke is one of the most common causes of acquired epilepsy, which can also result in disability and increased mortality rates particularly in elderly patients. No preventive treatment for post-stroke epilepsy is currently available. Development of such treatments has been greatly limited by the lack of biomarkers to reliably identify high-risk patients. The glymphatic system, including perivascular spaces (PVS), is the brain's waste clearance system, and enlargement or asymmetry of PVS (ePVS) is hypothesized to play a significant role in the pathogenesis of several neurological conditions. In this article, we discuss potential mechanisms for the role of perivascular spaces in the development of post-stroke epilepsy. Using advanced MR-imaging techniques, it has been shown that there is asymmetry and impairment of glymphatic function in the setting of ischemic stroke. Furthermore, studies have described a dysfunction of PVS in patients with different focal and generalized epilepsy syndromes. It is thought that inflammatory processes involving PVS and the blood-brain barrier, impairment of waste clearance, and sustained hypertension affecting the glymphatic system during a seizure may play a crucial role in epileptogenesis post-stroke. We hypothesize that impairment of the glymphatic system and asymmetry and dynamics of ePVS in the course of a stroke contribute to the development of PSE. Automated ePVS detection in stroke patients might thus assist in the identification of high-risk patients for post-stroke epilepsy trials. PLAIN LANGUAGE SUMMARY: Stroke often leads to epilepsy and is one of the main causes of epilepsy in elderly patients, with no preventative treatment available. The brain's waste removal system, called the glymphatic system which consists of perivascular spaces, may be involved. Enlargement or asymmetry of perivascular spaces could play a role in this and can be visualised with advanced brain imaging after a stroke. Detecting enlarged perivascular spaces in stroke patients could help identify those at risk for post-stroke epilepsy.

Adverse life events in patients with functional seizures: Assessment in clinical practice and association with long-term outcome.

BACKGROUND: A history of adverse life events (ALE) is a risk factor for functional seizures (FS). Their influence on long-term outcome remains unclear. International guidelines recommend assessing ALE in patients presenting with associated disorders. It is not clear to what extent patients evaluated for FS are regularly asked about ALE. OBJECTIVES: We hypothesised that the presence of ALE would relate to worse outcome at follow-up and, that the rate of detection of ALE in clinical work-up would be inferior to that based on self-report questionnaires. METHODS: 53 patients with FS from the National Centre for Epilepsy in Norway, aged 16-62 years were included. Symptom severity, health-related quality of life (HRQoL), and antecedent ALE were assessed at baseline. Medical records were examined for disclosure of ALE. At a mean of 70.45 (SD 29.0, range 22-130) months after inclusion, participants were inquired about FS status, FS-related health care utilization and HRQoL. FINDINGS: A history of emotional abuse documented in the medical record was an independent risk factor for worse HRQoL at follow-up. Prevalence of ALE documented in medical records was lower compared with rates measured by a self-report questionnaire. CONCLUSIONS: These findings indicate an association between antecedent ALE and HRQoL years after diagnosis. A substantial proportion of the adverse life events by a self-report questionnaire had not been documented in the clinical records. CLINICAL IMPLICATIONS: The supplemental use of a self-report questionnaire in the diagnostic work-up of patients with FS may be valuable for detecting ALE.

Reduced total number of enlarged perivascular spaces in post-traumatic epilepsy patients with unilateral lesions - a feasibility study.

BACKGROUND: We investigated the value of automated enlarged perivascular spaces (ePVS) quantification to distinguish chronic traumatic brain injury (TBI) patients with post-traumatic epilepsy (PTE+) from chronic TBI patients without PTE (PTE-) in a feasibility study. METHODS: Patients with and without PTE were recruited and underwent an MRI post-TBI. Multimodal auto identification of ePVS algorithm was applied to T1-weighted MRIs to segment ePVS. The total number of ePVS was calculated and corrected for white matter volume, and an asymmetry index (AI) derived. RESULTS: PTE was diagnosed in 7 out of the 99 participants (male=69) after a median time of less than one year since injury (range 10-22). Brain lesions were observed in all 7 PTE+ cases (unilateral=4, 57%; bilateral=3, 43%) as compared to 40 PTE- cases (total 44%; unilateral=17, 42%; bilateral=23, 58%). There was a significant difference between PTE+ (M=1.21e-4, IQR [8.89e-5]) and PTE- cases (M=2.79e-4, IQR [6.25e-5]) in total corrected numbers of ePVS in patients with unilateral lesions (p=0.024). No differences in AI, trauma severity and lesion volume were seen between groups. CONCLUSION: This study has shown that automated quantification of ePVS is feasible and provided initial evidence that individuals with PTE with unilateral lesions may have fewer ePVS compared to TBI patients without epilepsy. Further studies with larger sample sizes should be conducted to determine the value of ePVS quantification as a PTE-biomarker.

Screening of attention and executive functions in pediatric patients at a tertiary epilepsy center.

OBJECTIVE: Executive dysfunction is prevalent in children with epilepsy, and associated with poor psychosocial outcome. Sensitive and time effective tools are needed, which capture executive dysfunction across a wide range of impairment. The present study evaluates the applicability of EpiTrack Junior® (EpiTrackJr) as a screening tool at a tertiary epilepsy center, and explore how EpiTrackJr in combination with a subjective measure of everyday attention and executive functions (EFs) may provide clinically important information. METHODS: Retrospective study including 235 pediatric patients admitted to the Norwegian National Centre for Epilepsy. EpiTrackJr and Behavioral Rating Inventory of Executive Functioning (BRIEF) were used to assess attention and EFs. RESULTS: 27,7% obtained a score categorized as "average/unimpaired", 23% as "mildly impaired", and 47.7% as "significantly impaired" on EpiTrackJr. The distribution of age-corrected EpiTrackJr scores was satisfactory. Performance was related to numbers of anti-seizure medication (ASM load), comorbidity and IQ. We found a significant, but weak correlation between EpiTrackJr performance and the BRIEF Metacognitive Index (r = -0.236, n = 108, p=.014), but no significant correlation with the Behavioral Regulation Index (r = -0.178, n = 108, p=.065). SIGNIFICANCE: Our results indicate that EpiTrackJr is applicable as a screening tool for attention and EFs in pediatric patients at a tertiary epilepsy center. Impaired test performance was associated with greater ASM load, comorbidity and lower IQ. Performance based measures and behavior ratings likely capture different aspects of EFs. In combination, the two provide important and nonredundant information about the child's EFs in different settings.

Health-related quality of life in adults with drug-resistant focal epilepsy treated with modified Atkins diet in a randomized clinical trial.

Ketogenic diet, a high-fat, low-carbohydrate diet, is an established treatment for patients with severe epilepsy. We have previously reported a moderate reduction in seizure frequency after treatment with a modified Atkins diet. This study aimed to see whether dietary therapy impacts patients' health-related quality of life (HRQOL). In a randomized controlled design, we compared the change in self-reported HRQOL among adults with difficult-to-treat epilepsy after a 12-week diet intervention. Thirty-nine patients with drug-resistant focal epilepsy (age = 16-65 years) were randomized to eat a modified Atkins diet with maximum 16 g of carbohydrate per day (diet group, n = 19) or to continue eating habitual diet (control group, n = 20). No changes to the other epilepsy treatments were allowed. Patient-reported HRQOL was assessed with the Quality of Life in Epilepsy Inventory-89 (QOLIE-89). The diet group experienced a statistically significant improvement in mean total score of QOLIE-89 of 10 points compared to controls (p = .002). Moreover, although not statistically significant when using a cutoff of 50% seizure reduction, our data suggest an association between diet-induced reduction in seizure frequency and improvement in HRQOL. The improvement in HRQOL was not associated with diet-induced weight reduction.

Use of screening tools to assess comorbidities and adverse events in patients with epilepsy. A European Reference Network for Rare and Complex Epilepsies (EpiCARE) survey.

PURPOSE: As comorbidities can affect treatment decisions, quality of life, and prognosis in epilepsy, it is important that they are detected and addressed as soon as possible. Screening tools can help by rapidly assessing various additional challenges in epilepsy. METHODS: To map the use and perceived benefit of different screening instruments for quality of life, psychiatric comorbidity, and cognition, along with side effects from anti-seizure medication in Europe, we sent an online questionnaire to dedicated epilepsy centres departments within the European Reference Network for Rare and Complex Epilepsies (EpiCARE). RESULTS: Among the 40 hospitals in the EpiCARE network, we received responses from 25 (63%), with 28 individual respondents. Most respondents reported using screening for quality of life (86%) and psychiatric comorbidity (82%), but relatively few (14%) screen for sexual problems. Many (47) different tools were used for evaluation of cognitive dysfunction, but just a few (5) different tools were used to screen for adverse events. The optimization of individual patient care was one main reason given for using screening tools (58%-100% - depending on purpose of tool), another was research (50% - 88% - depending on purpose of tool). A major benefit of using screening tools perceived by the respondents is the detection of "hidden" comorbidity (67% - 90% - depending on purpose of tool). CONCLUSION: In the absence of a broad consensus regarding use of screening tools, practices vary considerably among epilepsy centres. Greater emphasis should be directed towards harmonizing use of screening tools. Future research should address how screening results influence treatment choices, and how these might affect clinical care.

The effect of attachment style on long-term outcomes in psychogenic nonepileptic seizures: Results from a prospective study.

INTRODUCTION: Insecure and fearful attachment styles have been reported in psychogenic nonepileptic seizures (PNES). We have investigated associations between long-term clinical outcome in PNES, parenting and attachment styles and demographic, clinical, and neuropsychiatric factors. MATERIAL AND METHODS: Patients aged at least 16 years and with documented PNES, according to criteria from the International League Against Epilepsy, were prospectively recruited to this study. They were assessed at baseline to determine clinical characteristics, experience of attachment and perceptions of experienced parenting styles, trauma history, dissociation, and health-related quality of life. At a mean of 70.45 (SD 29.0, range 22-130) months after inclusion, participants were contacted by telephone and asked about their current medical status and psychiatric/psychological interventions. RESULTS: Of 53 patients included in the study, 51 (96 %) provided follow-up data. Most (84.9 %) patients were female, and the mean age of PNES onset was 25.6 years. At follow-up, 20 patients (39 %) were free of PNES. Those patients that had achieved PNES freedom at follow-up had lower levels of attachment anxiety (p = 0.01) and reported to have experienced their fathers as less controlling (p = 0.02) and their mothers as more caring (p = 0.04) at baseline compared with those patients still suffering from PNES. Seizure freedom at follow-up was predicted by male gender, younger age at PNES onset, and less attachment anxiety. CONCLUSION: In our cohort from a tertiary epilepsy center the long-term prognosis of PNES is poor. Attachment anxiety is a risk factor for persistent PNES. It may be of therapeutic relevance to assess attachment patterns in patients with PNES.

Efficacy, tolerability and pharmacokinetic variability of brivaracetam in adults with difficult-to-treat epilepsy.

PURPOSE: Brivaracetam (BRV) is one of our latest antiseizure medications (ASMs). It is an analogue of levetiracetam with limited real-life experience. The purpose of this study was to evaluate clinical experience with BRV with focus on efficacy, tolerability and pharmacokinetic variability among adult patients with difficult-to-treat epilepsy. METHODS: We retrospectively collected clinical and laboratory data from patients aged > 18 years who initiated treatment with BRV during 2016-2019 and were followed for > one year or cessation of BRV. RESULTS: The study cohort consisted of 120 adults with drug-resistant epilepsy. Serum concentrations of BRV were available in 72 patients. After one-year follow-up, the retention rate of BRV was 52%. Fifty-seven patients (48%) were responders (>50 reduction of seizure frequency), of whom six became seizure free. Adverse effects were reported in 78 patients (65%); 37 (31%) experienced psychiatric problems like increased irritability, anxiety and depressive symptoms. The mean daily BRV dose was 159 mg (SD 80 mg) and the mean serum concentration 5.4 µmol/L (SD 4.1 µmol/L). In 24 patients, BRV replaced levetiracetam. Pharmacokinetic variability between patients was considerable; 14-fold variation in concentration/dose (C/D)-ratios. Concomitant use of enzyme-inducing ASMs decreased the C/D-ratio by 48%. There were no significant differences in serum concentrations between responders vs. non-responders, or those who experienced adverse effects or not. CONCLUSION: After > 1 year of treatment with BRV, we found a responder rate of 48% in adult patients with difficult-to-treat epilepsy. The drug was largely well tolerated, but one third experienced psychiatric adverse effects. The combination of clinical and pharmacokinetic data provides insight into factors contributing to efficacy and tolerability of new ASMs.

Reappraisal of the Medical Research Council Antiepileptic Drug Withdrawal Study: Contamination-adjusted and dose-response re-analysis.

OBJECTIVE: The 1991 Medical Research Council (MRC) Study compared seizure relapse for seizure-free patients randomized to withdraw vs continue of antiseizure medications (ASMs). We re-analyzed this trial to account for crossover between arms using contamination-adjusted intention to treat (CA ITT) methods, to explore dose-response curves, and to validate predictions against external data. ITT assesses the effect of being randomized to withdraw, as-treated analysis assesses the confounded effect of withdrawing, but CA ITT assesses the unconfounded effect of actually withdrawing. METHODS: CA ITT involves two stages. First, we used randomized arm to predict whether patients withdrew their ASM (logistic) or total daily ASM dose (linear). Second, we used those values to predict seizure occurrence (logistic). RESULTS: The trial randomized 503 patients to withdraw and 501 patients to continue ASMs. We found that 316 of 376 patients (88%) who were randomized to withdraw decreased their dose at every pre-seizure visit, compared with 35 of 424 (8%) who were randomized to continue (p < .01). Adjusted odds ratios of a 2-year seizure for those who withdrew vs those who did not was 1.3 (95% confidence interval [CI] 0.9-1.9) in the as-treated analysis, 2.5 (95% CI 1.9-3.4) comparing those randomized to withdraw vs continue for ITT, and 3.1 (95% CI 2.1-4.5) for CA ITT. Probabilities (withdrawal vs continue) were 28% vs 24% (as-treated), 40% vs 22% (ITT), and 43% vs 21% (CA ITT). Differences between ITT and CA ITT were greater when varying the predictor (reaching zero ASMs) or outcome (1-year seizures). As-treated dose-response curves demonstrated little to no effects, but larger effects in CA ITT analysis. MRC data overpredicted risk in Lossius data, with moderate discrimination (areas under the curve ~0.70). SIGNIFICANCE: CA ITT results (the effect of actually withdrawing ASMs on seizures) were slightly greater than ITT effects (the effect of recommend withdrawing ASMs on seizures). How these findings affect clinical practice must be individualized.

Norwegian population-based study of long-term effects, safety, and predictors of response of vagus nerve stimulation treatment in drug-resistant epilepsy: The NORPulse study.

OBJECTIVE: This study was undertaken to evaluate the efficacy of vagus nerve stimulation (VNS) over time, and to determine which patient groups derive the most benefit. METHODS: Long-term outcomes are reported in 436 epilepsy patients from a VNS quality registry (52.8% adults, 47.2% children), with a median follow-up of 75 months. Patients were stratified according to evolution of response into constant responders, fluctuating responders, and nonresponders. The effect was evaluated at 6, 12, 24, 36, and 60 months. Multivariate regression analysis was used to identify predictors of response. RESULTS: The cumulative probability of ≥50% seizure reduction was 60%; however, 15% of patients showed a fluctuating course. Of those becoming responders, 89.5% (230/257) did so within 2 years. A steady increase in effect was observed among constant responders, with 48.7% (19/39) of those becoming seizure-free and 29.3% (39/133) with ≥75% seizure reduction achieving these effects within 2-5 years. Some effect (25%-<50%) at 6 months was a positive predictor of becoming a responder (odds ratio [OR] = 10.18, p < .0001) and having ≥75% reduction at 2 years (OR = 3.34, p = .03). Patients without intellectual disability had ORs of 3.34 and 3.11 of having ≥75% reduction at 2 and 5 years, respectively, and an OR of 6.22 of being seizure-free at last observation. Patients with unchanged antiseizure medication over the observation period showed better responder rates at 2 (63.0% vs. 43.1%, p = .002) and 5 years (63.4% vs. 46.3%, p = .031) than patients whose antiseizure medication was modified. Responder rates were higher for posttraumatic (70.6%, p = .048) and poststroke epilepsies (75.0%, p = .05) than other etiologies (46.5%). SIGNIFICANCE: Our data indicate that the effect of VNS increases over time and that there are important clinical decision points at 6 and 24 months for evaluating and adjusting the treatment. There should be better selection of candidates, as certain patient groups and epilepsy etiologies respond more favorably.

Cognitive change after DBS in refractory epilepsy: A randomized-controlled trial.

OBJECTIVES: Deep brain stimulation of the anterior thalamic nucleus (ANT-DBS) reduces seizure frequency in patients with refractory epilepsy. There are, however, few studies on treatment-related changes in cognitive functions. The main objective of this study was to investigate cognitive changes in patients receiving ANT-DBS. We also explored whether possible effects were related to stimulation duration and whether change in seizure frequency was associated with cognitive changes. MATERIALS AND METHODS: Bilateral ANT electrodes were implanted in 18 patients with refractory epilepsy, aged 18-52 years. Immediately after implantation, patients were randomized to stimulation ON (n = 8) or OFF (n = 10) for the first 6 months (blinded phase). During the following 6-month open phase, both groups received stimulation. Neuropsychological assessments were conducted before implantation (T1), at the end of the blinded period (T2), and 1 year after implantation (T3). RESULTS: Groupwise comparisons across the three time points revealed changes in performance in two of 22 cognitive test scores: motor speed and sustained attention. We found no significant group differences in cognitive change from T1 to T2. Patients reported fewer symptoms of executive dysfunction after 12 months of stimulation. Patients showing significant improvement in seizure frequency had better performance in a measure of verbal learning. CONCLUSION: Our results indicate that ANT-DBS has very limited effects on cognitive functioning, as measured by formal tests after 6- or 12-month stimulation. ANT-DBS may have a positive influence on executive function. Our findings provide limited support for an association between change in seizure frequency and cognitive functioning.

Feasibility of transcutaneous auricular vagus nerve stimulation in treatment of drug resistant epilepsy: A multicenter prospective study.

BACKGROUND: Transcutaneous auricular vagus nerve stimulation (ta-VNS) is a new non-invasive technique developed as treatment option for drug resistant epilepsy. A few studies have been carried out showing that the efficacy and tolerability of ta-VNS is comparable with traditional implanted VNS but the feasibility of the therapy has been poorly described. This study aimed to explore potential clinical benefits of ta-VNS and to evaluate adaptation, compliance, as well as the usability of the device from a service design perspective. METHODS: A prospective, multicenter, clinical, investigator-initiated trial was conducted using the NEMOS® ta-VNS device. After eight weeks baseline, all subjects started ta-VNS with individually adjusted currents for four hours per day for six-months (first endpoint) followed by optional 12 months follow-up (second endpoint). The primary outcome was six months retention rate of ta-VNS therapy. Secondary outcomes included the user retention rate at 12 months follow-up, compliance, changes in scores of psychometric measures. For the study of feasibility, a service design questionnaire on medical devices used in the home was developed. RESULTS: In total 37 subjects had been included in the study after 45 months where the study was prematurely terminated due to recruitment problems and due to a high drop-out rate. Twenty-two subjects (59 %) completed the first six months of the study and in total six subjects (16 %) completed the following 12 months follow-up. The reasons for discontinuation were a mixture of medical and practical issues of which the majority were related to a combination of both. Those, who managed to continue to use ta-VNS throughout the study, gave generally higher scores for the device usability and compatibility with lifestyle. The study turned out to be inadequately powered to reach any conclusion in terms of the clinical benefits of ta-VNS but present an example of difficulties that are encountered in conducting high-quality studies with digital devices. CONCLUSION: The feasibility of ta-VNS therapy showed to be relatively modest which is most likely due to practical usability issues and lifestyle fits. The results of this study stress the importance of generating data based on patients experiences at an early stage during the development phase and when designing clinical trials on medical devices that depend on patient's active participation and motivation.