The effect of recurrent seizures on cognitive, behavioral, and quality-of-life outcomes after 12 months of monotherapy in adults with newly diagnosed or previously untreated partial epilepsy

Impact of Seizures While Driving Prior to Diagnosis in People With Focal Epilepsy: Motor Vehicle Accidents and Time to Diagnosis

OBJECTIVES

To identify the type, frequency, and consequences of seizures while driving (SzWD) in people with epilepsy before diagnosis.

METHODS

We performed a retrospective cohort study using the Human Epilepsy Project (HEP) to identify prediagnostic SzWD. Clinical descriptions from seizure diaries and medical records were used to classify seizure types and frequencies, time to diagnosis, and SzWD outcomes. Data were modeled using multiple logistic regression to assess for factors independently associated with SzWD.

RESULTS

32 prediagnostic SzWD were reported among 23/447 (5.1%) participants. Of them, 7 (30.4%) had more than 1. Six participants (26.1%) experienced SzWD as their first lifetime seizure. Most SzWD were focal with impaired awareness (n = 27, 84.4%). Of participants who had motor vehicle accidents (MVAs), 6 (42.9%) had no recollection. SzWD led to hospitalization in 11 people. The median time from first seizure to first SzWD was 304 days (IQR = 0-4,056 days). The median time between first SzWD and diagnosis was 64 days (IQR = 10-176.5 days). Employment was associated with a 3.95-fold increased risk of SzWD (95% CI 1.2-13.2, p = 0.03), and nonmotor seizures were associated with a 4.79-fold increased risk (95% CI 1.3-17.6, p = 0.02).

DISCUSSION

This study identifies the consequences of seizure-related MVAs and hospitalizations people experience before epilepsy diagnosis. This highlights the need for further research aimed at improving seizure awareness and improving time to diagnosis.

Psychobehavioural and Cognitive Adverse Events of Anti-Seizure Medications for the Treatment of Developmental and Epileptic Encephalopathies

The developmental and epileptic encephalopathies encompass a group of rare syndromes characterised by severe drug-resistant epilepsy with onset in childhood and significant neurodevelopmental comorbidities. The latter include intellectual disability, developmental delay, behavioural problems including attention-deficit hyperactivity disorder and autism spectrum disorder, psychiatric problems including anxiety and depression, speech impairment and sleep problems. Classical examples of developmental and epileptic encephalopathies include Dravet syndrome, Lennox-Gastaut syndrome and tuberous sclerosis complex. The mainstay of treatment is with multiple anti-seizure medications (ASMs); however, the ASMs themselves can be associated with psychobehavioural adverse events, and effects (negative or positive) on cognition and sleep. We have performed a targeted literature review of ASMs commonly used in the treatment of developmental and epileptic encephalopathies to discuss the latest evidence on their effects on behaviour, mood, cognition, sedation and sleep. The ASMs include valproate (VPA), clobazam, topiramate (TPM), cannabidiol (CBD), fenfluramine (FFA), levetiracetam (LEV), brivaracetam (BRV), zonisamide (ZNS), perampanel (PER), ethosuximide, stiripentol, lamotrigine (LTG), rufinamide, vigabatrin, lacosamide (LCM) and everolimus. Bromide, felbamate and other sodium channel ASMs are discussed briefly. Overall, the current evidence suggest that LEV, PER and to a lesser extent BRV are associated with psychobehavioural adverse events including aggressiveness and irritability; TPM and to a lesser extent ZNS are associated with language impairment and cognitive dulling/memory problems. Patients with a history of behavioural and psychiatric comorbidities may be more at risk of developing psychobehavioural adverse events. Topiramate and ZNS may be associated with negative effects in some aspects of cognition; CBD, FFA, LEV, BRV and LTG may have some positive effects, while the remaining ASMs do not appear to have a detrimental effect. All the ASMs are associated with sedation to a certain extent, which is pronounced during uptitration. Cannabidiol, PER and pregabalin may be associated with improvements in sleep, LTG is associated with insomnia, while VPA, TPM, LEV, ZNS and LCM do not appear to have detrimental effects. There was variability in the extent of evidence for each ASM: for many first-generation and some second-generation ASMs, there is scant documented evidence; however, their extensive use suggests favourable tolerability and safety (e.g. VPA); second-generation and some third-generation ASMs tend to have the most robust evidence documented over several years of use (TPM, LEV, PER, ZNS, BRV), while evidence is still being generated for newer ASMs such as CBD and FFA. Finally, we discuss how a variety of factors can affect mood, behaviour and cognition, and untangling the associations between the effects of the underlying syndrome and those of the ASMs can be challenging. In particular, there is enormous heterogeneity in cognitive, behavioural and developmental impairments that is complex and can change naturally over time; there is a lack of standardised instruments for evaluating these outcomes in developmental and epileptic encephalopathies, with a reliance on subjective evaluations by proxy (caregivers); and treatment regimes are complex involving multiple ASMs as well as other drugs.

Considering social determinants of health in the relationship between physical activity and exercise engagement and cognitive impairment among persons with epilepsy

Many persons with epilepsy (PWE) are not as active or physically fit as compared to the general population. This lack of engagement in physical activity has been attributed to a number of factors, few of which take into consideration the social determinants of health (SDH). In this perspective, we highlight how SDH are considered in explaining lower levels of physical activity engagement among PWE, particularly for those experiencing cognitive impairment. We also discuss how these data can be applied in research to yield a greater impact on the quality of life among PWE. Consideration of SDH allows for increased understanding of how cognition can be both a determinant of physical activity and an outcome of environments conducive to physical activity in PWE.

Antiepileptic drug monotherapy for epilepsy: a network meta-analysis of individual participant data

BACKGROUND

This is an updated version of the original Cochrane Review published in 2017. Epilepsy is a common neurological condition with a worldwide prevalence of around 1%. Approximately 60% to 70% of people with epilepsy will achieve a longer-term remission from seizures, and most achieve that remission shortly after starting antiepileptic drug treatment. Most people with epilepsy are treated with a single antiepileptic drug (monotherapy) and current guidelines from the National Institute for Health and Care Excellence (NICE) in the United Kingdom for adults and children recommend carbamazepine or lamotrigine as first-line treatment for focal onset seizures and sodium valproate for generalised onset seizures; however, a range of other antiepileptic drug (AED) treatments are available, and evidence is needed regarding their comparative effectiveness in order to inform treatment choices.

OBJECTIVES

To compare the time to treatment failure, remission and first seizure of 12 AEDs (carbamazepine, phenytoin, sodium valproate, phenobarbitone, oxcarbazepine, lamotrigine, gabapentin, topiramate, eventrate, zonisamide, eslicarbazepine acetate, lacosamide) currently used as monotherapy in children and adults with focal onset seizures (simple focal, complex focal or secondary generalised) or generalised tonic-clonic seizures with or without other generalised seizure types (absence, myoclonus).

SEARCH METHODS

For the latest update, we searched the following databases on 12 April 2021: the Cochrane Register of Studies (CRS Web), which includes PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP), the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Epilepsy Group Specialised Register and MEDLINE (Ovid, 1946 to April 09, 2021). We handsearched relevant journals and contacted pharmaceutical companies, original trial investigators and experts in the field.

SELECTION CRITERIA

We included randomised controlled trials of a monotherapy design in adults or children with focal onset seizures or generalised onset tonic-clonic seizures (with or without other generalised seizure types).

DATA COLLECTION AND ANALYSIS

This was an individual participant data (IPD) and network meta-analysis (NMA) review. Our primary outcome was 'time to treatment failure', and our secondary outcomes were 'time to achieve 12-month remission', 'time to achieve six-month remission', and 'time to first seizure post-randomisation'. We performed frequentist NMA to combine direct evidence with indirect evidence across the treatment network of 12 drugs. We investigated inconsistency between direct 'pairwise' estimates and NMA results via node splitting. Results are presented as hazard ratios (HRs) with 95% confidence intervals (CIs) and we assessed the certainty of the evidence using the CiNeMA approach, based on the GRADE framework. We have also provided a narrative summary of the most commonly reported adverse events.

MAIN RESULTS

IPD were provided for at least one outcome of this review for 14,789 out of a total of 22,049 eligible participants (67% of total data) from 39 out of the 89 eligible trials (43% of total trials). We could not include IPD from the remaining 50 trials in analysis for a variety of reasons, such as being unable to contact an author or sponsor to request data, data being lost or no longer available, cost and resources required to prepare data being prohibitive, or local authority or country-specific restrictions. No IPD were available from a single trial of eslicarbazepine acetate, so this AED could not be included in the NMA. Network meta-analysis showed high-certainty evidence that for our primary outcome, 'time to treatment failure', for individuals with focal seizures; lamotrigine performs better than most other treatments in terms of treatment failure for any reason and due to adverse events, including the other first-line treatment carbamazepine; HRs (95% CIs) for treatment failure for any reason for lamotrigine versus: eventrate 1.01 (0.88 to 1.20), zonisamide 1.18 (0.96 to 1.44), lacosamide 1.19 (0.90 to 1.58), carbamazepine 1.26 (1.10 to 1.44), oxcarbazepine 1.30 (1.02 to 1.66), sodium valproate 1.35 (1.09 to 1.69), phenytoin 1.44 (1.11 to 1.85), topiramate 1.50 (1.23 to 1.81), gabapentin 1.53 (1.26 to 1.85), phenobarbitone 1.97 (1.45 to 2.67). No significant difference between lamotrigine and eventrate was shown for any treatment failure outcome, and both AEDs seemed to perform better than all other AEDs. For people with generalised onset seizures, evidence was more limited and of moderate certainty; no other treatment performed better than first-line treatment sodium valproate, but there were no differences between sodium valproate, lamotrigine or eventrate in terms of treatment failure; HRs (95% CIs) for treatment failure for any reason for sodium valproate versus: lamotrigine 1.06 (0.81 to 1.37), eventrate 1.13 (0.89 to 1.42), gabapentin 1.13 (0.61 to 2.11), phenytoin 1.17 (0.80 to 1.73), oxcarbazepine 1.24 (0.72 to 2.14), topiramate 1.37 (1.06 to 1.77), carbamazepine 1.52 (1.18 to 1.96), phenobarbitone 2.13 (1.20 to 3.79), lacosamide 2.64 (1.14 to 6.09). Network meta-analysis also showed high-certainty evidence that for secondary remission outcomes, few notable differences were shown for either seizure type; for individuals with focal seizures, carbamazepine performed better than gabapentin (12-month remission) and sodium valproate (six-month remission). No differences between lamotrigine and any AED were shown for individuals with focal seizures, or between sodium valproate and other AEDs for individuals with generalised onset seizures. Network meta-analysis also showed high- to moderate-certainty evidence that, for 'time to first seizure,' in general, the earliest licensed treatments (phenytoin and phenobarbitone) performed better than the other treatments for individuals with focal seizures; phenobarbitone performed better than both first-line treatments carbamazepine and lamotrigine. There were no notable differences between the newer drugs (oxcarbazepine, topiramate, gabapentin, eventrate, zonisamide and lacosamide) for either seizure type. Generally, direct evidence (where available) and network meta-analysis estimates were numerically similar and consistent with confidence intervals of effect sizes overlapping. There was no important indication of inconsistency between direct and network meta-analysis results. The most commonly reported adverse events across all drugs were drowsiness/fatigue, headache or migraine, gastrointestinal disturbances, dizziness/faintness and rash or skin disorders; however, reporting of adverse events was highly variable across AEDs and across studies.

AUTHORS' CONCLUSIONS

High-certainty evidence demonstrates that for people with focal onset seizures, current first-line treatment options carbamazepine and lamotrigine, as well as newer drug eventrate, show the best profile in terms of treatment failure and seizure control as first-line treatments. For people with generalised tonic-clonic seizures (with or without other seizure types), current first-line treatment sodium valproate has the best profile compared to all other treatments, but lamotrigine and eventrate would be the most suitable alternative first-line treatments, particularly for those for whom sodium valproate may not be an appropriate treatment option. Further evidence from randomised controlled trials recruiting individuals with generalised tonic-clonic seizures (with or without other seizure types) is needed.

Factors involved in time reduction between seizure relapses in patients with epilepsy attending emergency rooms in Medellín, Colombia

BACKGROUND

Seizure relapses are the leading cause of admission to emergency rooms (ER) in people with epilepsy.

OBJECTIVE

To analyze administrative and clinical factors associated with the duration between seizure relapses in people with epilepsy admitted to the Neurological Institute of Colombia (Medellin) between July 2018 and July 2019.

MATERIALS AND METHODS

A retrospective follow-up study of 156 patients over 18 years old, diagnosed with epilepsy, and treated for over a year. The outcome variable was the time between seizure relapses, identified through the record of ER attendances. In addition, difficulties in the prescription filling process (delay, omission, or brand change) and clinical characteristics were analyzed as potential associated influence factors. The statistical analysis was performed using the Prentice, Williams & Peterson-Gap Time survival model for recurrent events. Finally, Adjusted Hazard Ratios (aHR) with 95% confidence intervals (95%CI) are also presented.

RESULTS

One hundred fifty-six patients were analyzed. Their average age of diagnosis was 15.5 years (SD = 22.5), the median number of monthly seizures was 3 (SD = 9.3), and 50.6% were women. Moreover, difficulties in the prescription filling process were associated with a time reduction between seizure relapses (aHR = 2.61; 95%CI 1.49-4.57), showing a similar impact as having a history of three or four types of events (aHR = 2.96; 95%CI 1.23-7.12) and neuropsychiatric comorbidity (aHR = 1.89; 95%CI 1.04-3.54).

CONCLUSION

Neuropsychiatric comorbidity, history of several types of events, and experiencing difficulties with prescription filling are associated with lower benefit from treatment to control seizure relapses.

Diagnostic Delay in Epilepsy: the Scope of the Problem

PURPOSE OF REVIEW

Diagnostic delay is an increasingly recognized issue in epilepsy. At the same time, there is a clear disparity between public awareness of epilepsy and that of other public health issues. A contributing factor for this seems to be a lack of studies testing interventions designed to improve seizure recognition. In this review, we summarize the main findings from recent studies investigating diagnostic delay in epilepsy, highlighting causes, consequences, and potential interventions in future research that may improve quality of care in this population.

RECENT FINDINGS

Building on prior evidence, diagnostic delay in patients with new-onset focal epilepsy has been identified as an important problem for patients with epilepsy. Such delay in diagnosis can lead to delayed treatment and potentially preventable morbidity and mortality including motor vehicle accidents. Nonmotor seizure semiology appears to be a major contributor for delay; such seizures are largely unrecognized when patients present to emergency departments for care. Improving recognition and diagnosis of recurrent nonmotor seizures in emergency departments represents a significant opportunity for improving time to diagnosis, particularly when patients present following a first lifetime motor seizure and meet diagnostic criteria for epilepsy. Diagnostic delay in epilepsy is a significant public health issue and recent studies have highlighted potential areas for intervention.

Gender differences in seizure recurrence and antiepileptic drug polytherapy predicting health-related quality of life of persons 1 year after diagnosis of epilepsy

PURPOSE

The aim of this study was to determine whether gender influences the prediction of health-related quality of life (HRQoL) in persons with newly diagnosed epilepsy (NDE).

METHODS

This was a 1-year longitudinal study. Persons with NDE were assessed with the Quality of Life in Epilepsy Inventory-31 (QOLIE-31), the Hospital Anxiety Depression Scale (HADS), the Stigma Scale, and the Rosenberg Self-esteem Scale. An analysis of covariance (ANCOVA) with interaction terms was used.

RESULTS

Among 134 adults with NDE, there were no gender differences in the scores of the QOLIE-31 and its subscales. A multivariate linear regression analysis showed that the HADS-anxiety scores at diagnosis (p = 0.005) and seizure recurrence after diagnosis (p = 0.050) negatively predicted QOLIE-31 scores in persons with NDE. There were significant effects of the gender interaction with seizure recurrence (F = 8.745, p = 0.004, partial eta² = 0.066) and antiepileptic drug (AED) polytherapy (F = 6.320, p = 0.013, partial eta² = 0.049) in the adjusted model. Specifically, seizure recurrence negatively predicted the QOLIE-31 scores only in men. By contrast, AED polytherapy negatively predicted the QOLIE-31 scores only in women.

CONCLUSIONS

There are gender differences in certain epilepsy-related factors predicting HRQoL at 1 year in persons with NDE.

Tumor-associated epilepsy in patients with brain metastases: necrosis-to-tumor ratio forecasts postoperative seizure freedom

Surgical resection is highly effective in the treatment of tumor-related epilepsy (TRE) in patients with brain metastases (BM). Nevertheless, some patients suffer from postoperative persistent epilepsy which negatively impacts health-related quality of life. Therefore, early identification of patients with potentially unfavorable seizure outcome after BM resection is important. Patients with TRE that had undergone surgery for BM at the authors’ institution between 2013 and 2018 were analyzed with regard to preoperatively identifiable risk factors for unfavorable seizure outcome. Tumor tissue and tumor necrosis ratios were assessed volumetrically. According to the classification of the International League Against Epilepsy (ILAE), seizure outcome was categorized as favorable (ILAE 1) and unfavorable (ILAE 2–6) after 3 months in order to avoid potential interference with adjuvant cancer treatment. Among all 38 patients undergoing neurosurgical treatment for BM with concomitant TRE, 34 patients achieved a favorable seizure outcome (90%). Unfavorable seizure outcome was significantly associated with larger tumor volumes (p = 0.012), a midline shift > 7 mm (p = 0.025), and a necrosis/tumor volume ratio > 0.2 (p = 0.047). The present study identifies preoperatively collectable risk factors for unfavorable seizure outcome in patients with BM and TRE. This might enable to preselect for highly vulnerable patients with postoperative persistent epilepsy who might benefit from accompanying neuro-oncological expertise during further systemical treatment regimes.

Gender differences in factors associated with resilience for health-related quality of life in persons with epilepsy

PURPOSE

We determined whether resilience factors such as self-efficacy, stress coping styles, and social support were differentially associated with health-related quality of life (HRQoL) in men and women with epilepsy after controlling for depression, anxiety, and daily-life stress.

METHODS

This was a cross-sectional study of 129 adults with epilepsy. The Quality of Life in Epilepsy Inventory-31 (QOLIE-31), Epilepsy Self-Efficacy Scale, Way of Stress Coping Checklist, Social Support Scale, Beck Depression Inventory (BDI), Beck Anxiety Inventory, and Daily Hassles Scale were used. Stepwise linear regression analyses were performed.

RESULTS

Except for medication effects, there were no gender differences in the QOLIE-31 and its subscales. The medication effects score was higher in men than in women after controlling for BDI scores. The BDI scores were independently associated with the QOLIE-31 score in men and women. Epilepsy self-efficacy was associated with the QOLIE-31 in men, whereas social support was associated with the QOLIE-31 in women. Coping strategies were associated with the QOLIE-31 in neither men nor women. Seizure frequency, daily-life stress, and anxiety were also negatively associated with the QOLIE-31, but only in men. The coefficients of determination were 0.637 and 0.587 in the men's and women's models, respectively.

CONCLUSIONS

The influence of self-efficacy and social support on HRQoL differed between men and women with epilepsy even after controlling for psychological distress. These findings could contribute to the development of successful gender-specific psychosocial interventions to improve HRQoL in men and women with epilepsy.

Sociocultural determinants and patterns of healthcare utilization for epilepsy care in Uganda

OBJECTIVE

Epilepsy is a global public health concern, with the majority of cases occurring in lower- and middle-income countries where the treatment gap remains formidable. In this study, we simultaneously explore how beliefs about epilepsy causation, perceived barriers to care, seizure disorder characteristics, and demographics influence the initial choice of healthcare for epilepsy and its impact on attaining biomedical care (BMC).

METHODS

This study utilized the baseline sample (n = 626) from a prospective cohort study of people with epilepsy (PWE) attending three public hospitals in Uganda (Mulago National Referral Hospital, Butabika National Referral Mental Hospital, and Mbarara Regional Referral Hospital) for epilepsy care. Patient and household demographics, clinical seizure disorder characteristics, and sociocultural questionnaires were administered. Logistic regression and principal component analyses (PCA) were conducted to examine associations with the choice of primary seizure treatment.

RESULTS

The sample was 49% female, and 24% lived in rural settings. A biomedical health facility was the first point of care for 355 (56.7%) participants, while 229 (36.6%) first sought care from a traditional healer and 42 (6.7%) from a pastoral healer. Preliminary inspection of candidate predictors using relaxed criteria for significance (p < 0.20) identified several factors potentially associated with a greater odds of seeking BMC first. Demographic predictors included older caredriver (decision-maker for the participant) age (odds ratio [OR]: 1.01, 95% confidence interval [CI]: [0.99, 1.02], p-value: 0.09), greater caredriver education level (OR = 1.21, 95% CI: [1.07, 1.37], p-value = 0.003), and lower ratio of sick to healthy family members (OR = 0.77 [0.56, 1.05], P = 0.097). For clinical predictors, none of the proposed predictors associated significantly with seeking BMC first. Self-report causation predictors associated with a greater odds of seeking BMC first included higher belief in biological causes of epilepsy (OR = 1.31 [0.92, 1.88], P = 0.133) and lower belief in socio-spiritual causes of epilepsy (OR = 0.68 [0.56, 0.84], P < 0.001). In the multivariate model, only higher caredriver education (OR = 1.19 [1.04, 1.36], P = 0.009) and lower belief in socio-spiritual causes of epilepsy (OR = 0.69 [0.56, 0.86], P < 0.01) remained as predictors of seeking BMC first. Additionally, PCA revealed a pattern which included high income with low beliefs in nonbiological causes of epilepsy as being associated with seeking BMC first (OR = 1.32 [1.12, 1.55], p = 0.001). Despite reaching some form of care faster, individuals seeking care from traditional or pastoral healers experienced a significant delay to eventual BMC (P < 0.001), with an average delay of more than two years (traditional healer: 2.53 years [1.98, 3.24]; pastoral care: 2.18 [1.21, 3.91]).

CONCLUSIONS

Coupled with low economic and educational status, belief in spiritual causation of epilepsy is a dominant determinant of opting for traditional or pastoral healing over BMC, regardless of concurrent belief in biological etiologies. There is a prolonged delay to eventual BMC for PWE who begin their treatment seeking with nonallopathic providers, and although nonallopathic healers provide PWE with benefits not provided by BMC, this notable delay likely prevents earlier administration of evidence-based care with known efficacy. Based on these findings, initiatives to increase public awareness of neurobiological causes of epilepsy and effectiveness of biomedical drug treatments may be effective in preventing delays to care, as would programs designed to facilitate cooperation and referral among traditional, faith-based, and biomedical providers. This article is part of the Special Issue "The Intersection of Culture, Resources, and Disease: Epilepsy Care in Uganda".

Lamotrigine versus carbamazepine monotherapy for epilepsy: an individual participant data review

BACKGROUND

This is an updated version of the original Cochrane Review published in Issue 11, 2006 of the Cochrane Database of Systematic Reviews.Epilepsy is a common neurological condition in which abnormal electrical discharges from the brain cause recurrent unprovoked seizures. It is believed that with effective drug treatment up to 70% of individuals with active epilepsy have the potential to become seizure-free, and to go into long-term remission shortly after starting drug therapy with a single antiepileptic drug (AED) in monotherapy.The correct choice of first-line AED for individuals with newly diagnosed seizures is of great importance. It is important that the choice of AEDs for an individual is made using the highest quality evidence regarding the potential benefits and harms of the various treatments.Carbamazepine or lamotrigine are recommended as first-line treatments for new onset focal seizures and as a first- or second-line treatment for generalised tonic-clonic seizures. Performing a synthesis of the evidence from existing trials will increase the precision of the results for outcomes relating to efficacy and tolerability and may assist in informing a choice between the two drugs.

OBJECTIVES

To review the time to treatment failure, remission and first seizure with lamotrigine compared to carbamazepine when used as monotherapy in people with focal onset seizures (simple or complex focal and secondarily generalised) or generalised onset tonic-clonic seizures (with or without other generalised seizure types).

SEARCH METHODS

We conducted the first searches for this review in 1997. For the most recent update, we searched the Cochrane Epilepsy Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO), MEDLINE, Clinical Trials.gov and the WHO International Clinical Trials Registry Platform on 26 February 2018, without language restrictions SELECTION CRITERIA: Randomised controlled trials comparing monotherapy with either carbamazepine or lamotrigine in children or adults with focal onset seizures or generalised onset tonic-clonic seizures DATA COLLECTION AND ANALYSIS: This was an individual participant data (IPD) review. Our primary outcome was time to treatment failure and our secondary outcomes were time to first seizure post randomisation, time to six-month, 12-month and 24-month remission, and incidence of adverse events. We used Cox proportional hazards regression models to obtain trial-specific estimates of hazard ratios (HRs) with 95% confidence intervals (CIs), using the generic inverse variance method to obtain the overall pooled HR and 95% CI.

MAIN RESULTS

We included 14 trials in this review. Individual participant data were available for 2572 participants out of 3787 eligible individuals from nine out of 14 trials: 68% of the potential data. For remission outcomes, a HR of less than one indicated an advantage for carbamazepine; and for first seizure and treatment failure outcomes, a HR of less than one indicated an advantage for lamotrigine.The main overall results were: time to treatment failure for any reason related to treatment (pooled HR adjusted for seizure type: 0.71, 95% CI 0.62 to 0.82, moderate-quality evidence), time to treatment failure due to adverse events (pooled HR adjusted for seizure type: 0.55 (95% CI 0.45 to 0.66, moderate-quality evidence), time to treatment failure due to lack of efficacy (pooled HR for all participants: 1.03 (95% CI 0.75 to 1.41), moderate-quality evidence) showing a significant advantage for lamotrigine compared to carbamazepine in terms of treatment failure for any reason related to treatment and treatment failure due to adverse events, but no different between drugs for treatment failure due to lack of efficacy.Time to first seizure (pooled HR adjusted for seizure type: 1.26, 95% CI 1.12 to 1.41, high-quality evidence) and time to six-month remission (pooled HR adjusted for seizure type: 0.86, 95% CI 0.76 to 0.97, high-quality evidence), showed a significant advantage for carbamazepine compared to lamotrigine for first seizure and six-month remission. We found no difference between the drugs for time to 12-month remission (pooled HR for all participants 0.91, 95% CI 0.77 to 1.07, high-quality evidence) or time to 24-month remission (HR for all participants 1.00, 95% CI 0.80 to 1.25, high-quality evidence), however only two trials followed up participants for more than one year so evidence is limited.The results of this review are applicable mainly to individuals with focal onset seizures; 88% of included individuals experienced seizures of this type at baseline. Up to 50% of the limited number of individuals classified as experiencing generalised onset seizures at baseline may have had their seizure type misclassified, therefore we recommend caution when interpreting the results of this review for individuals with generalised onset seizures.The most commonly reported adverse events for both of the drugs across all of the included trials were dizziness, fatigue, gastrointestinal disturbances, headache and skin problems. The rate of adverse events was similar across the two drugs.The methodological quality of the included trials was generally good, however there is some evidence that the design choice of masked or open-label treatment may have influenced the treatment failure and withdrawal rates of the trials. Hence, we judged the quality of the evidence for the primary outcome of treatment failure to be moderate for individuals with focal onset seizures and low for individuals with generalised onset seizures. For efficacy outcomes (first seizure, remission), we judged the quality of evidence to be high for individuals with focal onset seizures and moderate for individuals with generalised onset seizures.

AUTHORS' CONCLUSIONS

Moderate quality evidence indicates that treatment failure for any reason related to treatment or due to adverse events occurs significantly earlier on carbamazepine than lamotrigine, but the results for time to first seizure suggested that carbamazepine may be superior in terms of seizure control. The choice between these first-line treatments must be made with careful consideration. We recommend that future trials should be designed to the highest quality possible with consideration of masking, choice of population, classification of seizure type, duration of follow-up, choice of outcomes and analysis, and presentation of results.

Antiepileptic drug monotherapy for epilepsy: a network meta-analysis of individual participant data

BACKGROUND

Epilepsy is a common neurological condition with a worldwide prevalence of around 1%. Approximately 60% to 70% of people with epilepsy will achieve a longer-term remission from seizures, and most achieve that remission shortly after starting antiepileptic drug treatment. Most people with epilepsy are treated with a single antiepileptic drug (monotherapy) and current guidelines from the National Institute for Health and Care Excellence (NICE) in the United Kingdom for adults and children recommend carbamazepine or lamotrigine as first-line treatment for partial onset seizures and sodium valproate for generalised onset seizures; however a range of other antiepileptic drug (AED) treatments are available, and evidence is needed regarding their comparative effectiveness in order to inform treatment choices.

OBJECTIVES

To compare the time to withdrawal of allocated treatment, remission and first seizure of 10 AEDs (carbamazepine, phenytoin, sodium valproate, phenobarbitone, oxcarbazepine, lamotrigine, gabapentin, topiramate, levetiracetam, zonisamide) currently used as monotherapy in children and adults with partial onset seizures (simple partial, complex partial or secondary generalised) or generalised tonic-clonic seizures with or without other generalised seizure types (absence, myoclonus).

SEARCH METHODS

We searched the following databases: Cochrane Epilepsy's Specialised Register, CENTRAL, MEDLINE and SCOPUS, and two clinical trials registers. We handsearched relevant journals and contacted pharmaceutical companies, original trial investigators, and experts in the field. The date of the most recent search was 27 July 2016.

SELECTION CRITERIA

We included randomised controlled trials of a monotherapy design in adults or children with partial onset seizures or generalised onset tonic-clonic seizures (with or without other generalised seizure types).

DATA COLLECTION AND ANALYSIS

This was an individual participant data (IPD) review and network meta-analysis. Our primary outcome was 'time to withdrawal of allocated treatment', and our secondary outcomes were 'time to achieve 12-month remission', 'time to achieve six-month remission', 'time to first seizure post-randomisation', and 'occurrence of adverse events'. We presented all time-to-event outcomes as Cox proportional hazard ratios (HRs) with 95% confidence intervals (CIs). We performed pairwise meta-analysis of head-to-head comparisons between drugs within trials to obtain 'direct' treatment effect estimates and we performed frequentist network meta-analysis to combine direct evidence with indirect evidence across the treatment network of 10 drugs. We investigated inconsistency between direct estimates and network meta-analysis via node splitting. Due to variability in methods and detail of reporting adverse events, we have not performed an analysis. We have provided a narrative summary of the most commonly reported adverse events.

MAIN RESULTS

IPD was provided for at least one outcome of this review for 12,391 out of a total of 17,961 eligible participants (69% of total data) from 36 out of the 77 eligible trials (47% of total trials). We could not include IPD from the remaining 41 trials in analysis for a variety of reasons, such as being unable to contact an author or sponsor to request data, data being lost or no longer available, cost and resources required to prepare data being prohibitive, or local authority or country-specific restrictions.We were able to calculate direct treatment effect estimates for between half and two thirds of comparisons across the outcomes of the review, however for many of the comparisons, data were contributed by only a single trial or by a small number of participants, so confidence intervals of estimates were wide.Network meta-analysis showed that for the primary outcome 'Time to withdrawal of allocated treatment,' for individuals with partial seizures; levetiracetam performed (statistically) significantly better than current first-line treatment carbamazepine and other current first-line treatment lamotrigine performed better than all other treatments (aside from levetiracetam); carbamazepine performed significantly better than gabapentin and phenobarbitone (high-quality evidence). For individuals with generalised onset seizures, first-line treatment sodium valproate performed significantly better than carbamazepine, topiramate and phenobarbitone (moderate- to high-quality evidence). Furthermore, for both partial and generalised onset seizures, the earliest licenced treatment, phenobarbitone seems to perform worse than all other treatments (moderate- to high-quality evidence).Network meta-analysis also showed that for secondary outcomes 'Time to 12-month remission of seizures' and 'Time to six-month remission of seizures,' few notable differences were shown for either partial or generalised seizure types (moderate- to high-quality evidence). For secondary outcome 'Time to first seizure,' for individuals with partial seizures; phenobarbitone performed significantly better than both current first-line treatments carbamazepine and lamotrigine; carbamazepine performed significantly better than sodium valproate, gabapentin and lamotrigine. Phenytoin also performed significantly better than lamotrigine (high-quality evidence). In general, the earliest licenced treatments (phenytoin and phenobarbitone) performed better than the other treatments for both seizure types (moderate- to high-quality evidence).Generally, direct evidence and network meta-analysis estimates (direct plus indirect evidence) were numerically similar and consistent with confidence intervals of effect sizes overlapping.The most commonly reported adverse events across all drugs were drowsiness/fatigue, headache or migraine, gastrointestinal disturbances, dizziness/faintness and rash or skin disorders.

AUTHORS' CONCLUSIONS

Overall, the high-quality evidence provided by this review supports current guidance (e.g. NICE) that carbamazepine and lamotrigine are suitable first-line treatments for individuals with partial onset seizures and also demonstrates that levetiracetam may be a suitable alternative. High-quality evidence from this review also supports the use of sodium valproate as the first-line treatment for individuals with generalised tonic-clonic seizures (with or without other generalised seizure types) and also demonstrates that lamotrigine and levetiracetam would be suitable alternatives to either of these first-line treatments, particularly for those of childbearing potential, for whom sodium valproate may not be an appropriate treatment option due to teratogenicity.

Antiepileptic drug monotherapy for epilepsy: a network meta-analysis of individual participant data

BACKGROUND

Epilepsy is a common neurological condition with a worldwide prevalence of around 1%. Approximately 60% to 70% of people with epilepsy will achieve a longer-term remission from seizures, and most achieve that remission shortly after starting antiepileptic drug treatment. Most people with epilepsy are treated with a single antiepileptic drug (monotherapy) and current guidelines from the National Institute for Health and Care Excellence (NICE) in the United Kingdom for adults and children recommend carbamazepine or lamotrigine as first-line treatment for partial onset seizures and sodium valproate for generalised onset seizures; however a range of other antiepileptic drug (AED) treatments are available, and evidence is needed regarding their comparative effectiveness in order to inform treatment choices.

OBJECTIVES

To compare the time to withdrawal of allocated treatment, remission and first seizure of 10 AEDs (carbamazepine, phenytoin, sodium valproate, phenobarbitone, oxcarbazepine, lamotrigine, gabapentin, topiramate, levetiracetam, zonisamide) currently used as monotherapy in children and adults with partial onset seizures (simple partial, complex partial or secondary generalised) or generalised tonic-clonic seizures with or without other generalised seizure types (absence, myoclonus).

SEARCH METHODS

We searched the following databases: Cochrane Epilepsy's Specialised Register, CENTRAL, MEDLINE and SCOPUS, and two clinical trials registers. We handsearched relevant journals and contacted pharmaceutical companies, original trial investigators, and experts in the field. The date of the most recent search was 27 July 2016.

SELECTION CRITERIA

We included randomised controlled trials of a monotherapy design in adults or children with partial onset seizures or generalised onset tonic-clonic seizures (with or without other generalised seizure types).

DATA COLLECTION AND ANALYSIS

This was an individual participant data (IPD) review and network meta-analysis. Our primary outcome was 'time to withdrawal of allocated treatment', and our secondary outcomes were 'time to achieve 12-month remission', 'time to achieve six-month remission', 'time to first seizure post-randomisation', and 'occurrence of adverse events'. We presented all time-to-event outcomes as Cox proportional hazard ratios (HRs) with 95% confidence intervals (CIs). We performed pairwise meta-analysis of head-to-head comparisons between drugs within trials to obtain 'direct' treatment effect estimates and we performed frequentist network meta-analysis to combine direct evidence with indirect evidence across the treatment network of 10 drugs. We investigated inconsistency between direct estimates and network meta-analysis via node splitting. Due to variability in methods and detail of reporting adverse events, we have not performed an analysis. We have provided a narrative summary of the most commonly reported adverse events.

MAIN RESULTS

IPD was provided for at least one outcome of this review for 12,391 out of a total of 17,961 eligible participants (69% of total data) from 36 out of the 77 eligible trials (47% of total trials). We could not include IPD from the remaining 41 trials in analysis for a variety of reasons, such as being unable to contact an author or sponsor to request data, data being lost or no longer available, cost and resources required to prepare data being prohibitive, or local authority or country-specific restrictions.We were able to calculate direct treatment effect estimates for between half and two thirds of comparisons across the outcomes of the review, however for many of the comparisons, data were contributed by only a single trial or by a small number of participants, so confidence intervals of estimates were wide.Network meta-analysis showed that for the primary outcome 'Time to withdrawal of allocated treatment,' for individuals with partial seizures; levetiracetam performed (statistically) significantly better than both current first-line treatments carbamazepine and lamotrigine; lamotrigine performed better than all other treatments (aside from levetiracetam), and carbamazepine performed significantly better than gabapentin and phenobarbitone (high-quality evidence). For individuals with generalised onset seizures, first-line treatment sodium valproate performed significantly better than carbamazepine, topiramate and phenobarbitone (moderate- to high-quality evidence). Furthermore, for both partial and generalised onset seizures, the earliest licenced treatment, phenobarbitone seems to perform worse than all other treatments (moderate- to high-quality evidence).Network meta-analysis also showed that for secondary outcomes 'Time to 12-month remission of seizures' and 'Time to six-month remission of seizures,' few notable differences were shown for either partial or generalised seizure types (moderate- to high-quality evidence). For secondary outcome 'Time to first seizure,' for individuals with partial seizures; phenobarbitone performed significantly better than both current first-line treatments carbamazepine and lamotrigine; carbamazepine performed significantly better than sodium valproate, gabapentin and lamotrigine. Phenytoin also performed significantly better than lamotrigine (high-quality evidence). In general, the earliest licenced treatments (phenytoin and phenobarbitone) performed better than the other treatments for both seizure types (moderate- to high-quality evidence).Generally, direct evidence and network meta-analysis estimates (direct plus indirect evidence) were numerically similar and consistent with confidence intervals of effect sizes overlapping.The most commonly reported adverse events across all drugs were drowsiness/fatigue, headache or migraine, gastrointestinal disturbances, dizziness/faintness and rash or skin disorders.

AUTHORS' CONCLUSIONS

Overall, the high-quality evidence provided by this review supports current guidance (e.g. NICE) that carbamazepine and lamotrigine are suitable first-line treatments for individuals with partial onset seizures and also demonstrates that levetiracetam may be a suitable alternative. High-quality evidence from this review also supports the use of sodium valproate as the first-line treatment for individuals with generalised tonic-clonic seizures (with or without other generalised seizure types) and also demonstrates that lamotrigine and levetiracetam would be suitable alternatives to either of these first-line treatments, particularly for those of childbearing potential, for whom sodium valproate may not be an appropriate treatment option due to teratogenicity.

Low-frequency stimulation of the primary focus retards positive transfer of secondary focus

Positive transfer of secondary focus (PTS) refers to new epileptogenesis outside the primary focus and is minimally controlled by existing treatments. Low-frequency stimulation (LFS) has benefits on the onset of epilepsy and epileptogenesis. However, it's unclear whether LFS can retard the PTS in epilepsy. Here we found that PTS at both contralateral amygdala and ipsilateral hippocampus were promoted after the primary focus was fully kindled in rat kindling model. The promotion of PTS at the mirror focus started when the primary kindling acquisition reached focal seizures. LFS retarded the promotion of PTS when it was applied at the primary focus during its kindling acquisition, while it only slightly retarded the promotion of PTS when applied after generalized seizures. Meanwhile, we found the expression of potassium chloride cotransporter 2 (KCC2) decreased during PTS, and LFS reversed this. Further, the decreased expression of KCC2 was verified in patients with PTS. These findings suggest that LFS may be a potential therapeutic approach for PTS in epilepsy.

Lamotrigine versus carbamazepine monotherapy for epilepsy: an individual participant data review

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 1, 2006 of the Cochrane Database of Systematic Reviews.Epilepsy is a common neurological condition in which abnormal electrical discharges from the brain cause recurrent unprovoked seizures. It is believed that with effective drug treatment up to 70% of individuals with active epilepsy have the potential to become seizure-free and to go into long-term remission shortly after starting drug therapy with a single antiepileptic drug (AED) in monotherapy.The correct choice of first-line antiepileptic therapy for individuals with newly diagnosed seizures is of great importance. It is important that the choice of AEDs for an individual is made using the highest quality evidence regarding the potential benefits and harms of the various treatments. It is also important that the effectiveness and tolerability of AEDs appropriate to given seizure types are compared to one another.Carbamazepine or lamotrigine are first-line recommended treatments for new onset partial seizures and as a first- or second-line treatment for generalised tonic-clonic seizures. Performing a synthesis of the evidence from existing trials will increase the precision of the results for outcomes relating to efficacy and tolerability and may assist in informing a choice between the two drugs.

OBJECTIVES

To review the time to withdrawal, remission and first seizure with lamotrigine compared to carbamazepine when used as monotherapy in people with partial onset seizures (simple or complex partial and secondarily generalised) or generalised onset tonic-clonic seizures (with or without other generalised seizure types).

SEARCH METHODS

The first searches for this review were run in 1997. For the most recent update we searched the Cochrane Epilepsy Group Specialized Register (17 October 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO, 17 October 2016) and MEDLINE (Ovid, 1946 to 17 October 2016). We imposed no language restrictions. We also contacted pharmaceutical companies and trial investigators.

SELECTION CRITERIA

Randomised controlled trials in children or adults with partial onset seizures or generalised onset tonic-clonic seizures comparing monotherapy with either carbamazepine or lamotrigine.

DATA COLLECTION AND ANALYSIS

This was an individual participant data (IPD) review. Our primary outcome was time to withdrawal of allocated treatment and our secondary outcomes were time to first seizure post-randomisation, time to six-month, 12-month and 24-month remission, and incidence of adverse events. We used Cox proportional hazards regression models to obtain trial-specific estimates of hazard ratios (HRs) with 95% confidence intervals (CIs), using the generic inverse variance method to obtain the overall pooled HR and 95% CI.

MAIN RESULTS

We included 13 studies in this review. Individual participant data were available for 2572 participants out of 3394 eligible individuals from nine out of 13 trials: 78% of the potential data. For remission outcomes, a HR < 1 indicated an advantage for carbamazepine and for first seizure and withdrawal outcomes a HR < 1 indicated an advantage for lamotrigine.The main overall results (pooled HR adjusted for seizure type) were: time to withdrawal of allocated treatment (HR 0.72, 95% CI 0.63 to 0.82), time to first seizure (HR 1.22, 95% CI 1.09 to 1.37) and time to six-month remission (HR 0.84, 95% CI 0.74 to 0.94), showing a significant advantage for lamotrigine compared to carbamazepine for withdrawal but a significant advantage for carbamazepine compared to lamotrigine for first seizure and six-month remission. We found no difference between the drugs for time to 12-month remission (HR 0.91, 95% CI 0.77 to 1.07) or time to 24-month remission (HR 1.00, 95% CI 0.80 to 1.25), however only two trials followed up participants for more than one year so the evidence is limited.The results of this review are applicable mainly to individuals with partial onset seizures; 88% of included individuals experienced seizures of this type at baseline. Up to 50% of the limited number of individuals classified as experiencing generalised onset seizures at baseline may have had their seizure type misclassified, therefore we recommend caution when interpreting the results of this review for individuals with generalised onset seizures.The most commonly reported adverse events for both of the drugs across all of the included trials were dizziness, fatigue, gastrointestinal disturbances, headache and skin problems. The rate of adverse events was similar across the two drugs.The methodological quality of the included trials was generally good, however there is some evidence that the design choice of masked or open-label treatment may have influenced the withdrawal rates of the trials. Hence, we judged the quality of the evidence for the primary outcome of treatment withdrawal to be moderate for individuals with partial onset seizures and low for individuals with generalised onset seizures. For efficacy outcomes (first seizure, remission), we judged the quality of evidence to be high for individuals with partial onset seizures and moderate for individuals with generalised onset seizures.

AUTHORS' CONCLUSIONS

Lamotrigine was significantly less likely to be withdrawn than carbamazepine but the results for time to first seizure suggested that carbamazepine may be superior in terms of seizure control. A choice between these first-line treatments must be made with careful consideration. We recommend that future trials should be designed to the highest quality possible with consideration of masking, choice of population, classification of seizure type, duration of follow-up, choice of outcomes and analysis, and presentation of results.

Seizure control as a new metric in assessing efficacy of tumor treatment in low-grade glioma trials

Patients with low-grade glioma frequently have brain tumor-related epilepsy, which is more common than in patients with high-grade glioma. Treatment for tumor-associated epilepsy usually comprises a combination of surgery, anti-epileptic drugs (AEDs), chemotherapy, and radiotherapy. Response to tumor-directed treatment is measured primarily by overall survival and progression-free survival. However, seizure frequency has been observed to respond to tumor-directed treatment with chemotherapy or radiotherapy. A review of the current literature regarding seizure assessment for low-grade glioma patients reveals a heterogeneous manner in which seizure response has been reported. There is a need for a systematic approach to seizure assessment and its influence on health-related quality-of-life outcomes in patients enrolled in low-grade glioma therapeutic trials. In view of the need to have an adjunctive metric of tumor response in these patients, a method of seizure assessment as a metric in brain tumor treatment trials is proposed.