Supporting the ambulance service to safely convey fewer patients to hospital by developing a risk prediction tool: Risk of Adverse Outcomes after a Suspected Seizure (RADOSS)-protocol for the mixed-methods observational RADOSS project

INTRODUCTION

Ambulances services are asked to further reduce avoidable conveyances to emergency departments (EDs). Risk of Adverse Outcomes after a Suspected Seizure seeks to support this by: (1) clarifying the risks of conveyance and non-conveyance, and (2) developing a risk prediction tool for clinicians to use 'on scene' to estimate the benefits an individual would receive if conveyed to ED and risks if not.

METHODS AND ANALYSIS

Mixed-methods, multi-work package (WP) project. For WP1 and WP2 we shall use an existing linked data set that tracks urgent and emergency care (UEC) use of persons served by one English regional ambulance service. Risk tools are specific to clinical scenarios. We shall use suspected seizures in adults as an exemplar.WP1: Form a cohort of patients cared for a seizure by the service during 2019/2020. It, and nested Knowledge Exchange workshops with clinicians and service users, will allow us to: determine the proportions following conveyance and non-conveyance that die and/or recontact UEC system within 3 (/30) days; quantify the proportion of conveyed incidents resulting in 'avoidable ED attendances' (AA); optimise risk tool development; and develop statistical models that, using information available 'on scene', predict the risk of death/recontact with the UEC system within 3 (/30) days and the likelihood of an attendance at ED resulting in an AA.WP2: Form a cohort of patients cared for a seizure during 2021/2022 to 'temporally' validate the WP1 predictive models.WP3: Complete the 'next steps' workshops with stakeholders. Using nominal group techniques, finalise plans to develop the risk tool for clinical use and its evaluation.

ETHICS AND DISSEMINATION

WP1a and WP2 will be conducted under database ethical approval (IRAS 307353) and Confidentiality Advisory Group (22/CAG/0019) approval. WP1b and WP3 have approval from the University of Liverpool Central Research Ethics Committee (11450). We shall engage in proactive dissemination and knowledge mobilisation to share findings with stakeholders and maximise evidence usage.

Acute seizure risk in patients with encephalitis: development and validation of clinical prediction models from two independent prospective multicentre cohorts

Objective

In patients with encephalitis, the development of acute symptomatic seizures is highly variable, but when present is associated with a worse outcome. We aimed to determine the factors associated with seizures in encephalitis and develop a clinical prediction model.

Methods

We analysed 203 patients from 24 English hospitals (2005-2008) (Cohort 1). Outcome measures were seizures prior to and during admission, inpatient seizures and status epilepticus. A binary logistic regression risk model was converted to a clinical score and independently validated on an additional 233 patients from 31 UK hospitals (2013-2016) (Cohort 2).

Results

In Cohort 1, 121 (60%) patients had a seizure including 103 (51%) with inpatient seizures. Admission Glasgow Coma Scale (GCS) ≤8/15 was predictive of subsequent inpatient seizures (OR (95% CI) 5.55 (2.10 to 14.64), p<0.001), including in those without a history of prior seizures at presentation (OR 6.57 (95% CI 1.37 to 31.5), p=0.025).A clinical model of overall seizure risk identified admission GCS along with aetiology (autoantibody-associated OR 11.99 (95% CI 2.09 to 68.86) and Herpes simplex virus 3.58 (95% CI 1.06 to 12.12)) (area under receiver operating characteristics curve (AUROC) =0.75 (95% CI 0.701 to 0.848), p<0.001). The same model was externally validated in Cohort 2 (AUROC=0.744 (95% CI 0.677 to 0.811), p<0.001). A clinical scoring system for stratifying inpatient seizure risk by decile demonstrated good discrimination using variables available on admission; age, GCS and fever (AUROC=0.716 (95% CI 0.634 to 0.798), p<0.001) and once probable aetiology established (AUROC=0.761 (95% CI 0.6840.839), p<0.001).

Conclusion

Age, GCS, fever and aetiology can effectively stratify acute seizure risk in patients with encephalitis. These findings can support the development of targeted interventions and aid clinical trial design for antiseizure medication prophylaxis.

Socioeconomic and health factors related to polypharmacy and medication management: analysis of a Household Health Survey in North West Coast England

OBJECTIVES

To examine the socioeconomic and demographic drivers associated with polypharmacy (5-9 medicines), extreme polypharmacy (9-20 medicines) and increased medication count.

DESIGN, SETTING AND PARTICIPANTS

A total of 5509 participants, from two waves of the English North West Coast, Household Health Survey were analysed OUTCOME MEASURES: Logistic regression modelling was used to find associations with polypharmacy and extreme polypharmacy. A negative binomial regression identified associations with increased medication count. Descriptive statistics explored associations with medication management.

RESULTS

Age and number of health conditions account for the greatest odds of polypharmacy. ORs (95% CI) were greatest for those aged 65+ (3.87, 2.45 to 6.13) and for those with ≥5 health conditions (10.87, 5.94 to 19.88). Smaller odds were seen, for example, in those prescribed cardiovascular medications (3.08, 2.36 to 4.03), or reporting >3 emergency attendances (1.97, 1.23 to 3.17). Extreme polypharmacy was associated with living in a deprived neighbourhood (1.54, 1.06 to 2.26). The greatest risk of increased medication count was associated with age, number of health conditions and use of primary care services. Relative risks (95% CI) were greatest for those aged 65+ (2.51, 2.23 to 2.82), those with ≥5 conditions (10.26, 8.86 to 11.88) or those reporting >18 primary care visits (2.53, 2.18 to 2.93). Smaller risks were seen in, for example, respondents with higher levels of income deprivation (1.35, 1.03 to 1.77). Polypharmic respondents were more likely to report medication management difficulties associated with taking more than one medicine at a time (p<0.001). Furthermore, individuals reporting a mental health condition, were significantly more likely to consistently report difficulties managing their medication (p<0.001).

CONCLUSION

Age and number of health conditions are most associated with polypharmacy. Thus, delaying or preventing the onset of long-term conditions may help to reduce polypharmacy. Interventions to reduce income inequalities and health inequalities generally could support a reduction in polypharmacy, however, more research is needed in this area. Furthermore, increased prevention and support, particularly with medication management, for those with mental health conditions may reduce adverse medication effects.

High-mobility group box 1 as a predictive biomarker for drug-resistant epilepsy: A proof-of-concept study

Currently no sensitive and specific biomarkers exist to predict drug-resistant epilepsy. We determined whether blood levels of high-mobility group box 1 (HMGB1), a mediator of neuroinflammation implicated in drug-resistant epilepsies, identifies patients with drug-resistant seizures. Patients with drug-resistant epilepsy express significantly higher levels of blood HMGB1 than those with drug-responsive, well-controlled seizures and healthy controls. No correlation existed between blood HMGB1 levels and total pretreatment seizure count or days since last seizure at new epilepsy diagnosis, indicating that blood HMGB1 does not solely reflect ongoing seizures. HMGB1 distinguishes with high specificity and selectivity drug-resistant versus drug-responsive patients. This protein therefore has potential clinical utility to act as a biomarker for predicting response to therapy, which should be addressed in prospective clinical studies.

Thalamohippocampal atrophy in focal epilepsy of unknown cause at the time of diagnosis

BACKGROUND AND PURPOSE

Patients with chronic focal epilepsy may have atrophy of brain structures important for the generation and maintenance of seizures. However, little research has been conducted in patients with newly diagnosed focal epilepsy (NDfE), despite it being a crucial point in time for understanding the underlying biology of the disorder. We aimed to determine whether patients with NDfE show evidence of volumetric abnormalities of subcortical structures.

METHODS

Eighty-two patients with NDfE and 40 healthy controls underwent magnetic resonance imaging scanning using a standard clinical protocol. Volume estimation of the left and right hippocampus, thalamus, caudate nucleus, putamen and cerebral hemisphere was performed for all participants and normalised to whole brain volume. Volumes lower than two standard deviations below the control mean were considered abnormal. Volumes were analysed with respect to patient clinical characteristics, including treatment outcome 12 months after diagnosis.

RESULTS

Volume of the left hippocampus (p_(FDR-corr)  = 0.04) and left (p_(FDR-corr)  = 0.002) and right (p_(FDR-corr)  = 0.04) thalamus was significantly smaller in patients relative to controls. Relative to the normal volume limits in controls, 11% patients had left hippocampal atrophy, 17% had left thalamic atrophy and 9% had right thalamic atrophy. We did not find evidence of a relationship between volumes and future seizure control or with other clinical characteristics of epilepsy.

CONCLUSIONS

Volumetric abnormalities of structures known to be important for the generation and maintenance of focal seizures are established at the time of epilepsy diagnosis and are not necessarily a result of the chronicity of the disorder.

Study protocol for a pragmatic randomised controlled trial comparing the effectiveness and cost-effectiveness of levetiracetam and zonisamide versus standard treatments for epilepsy: a comparison of standard and new antiepileptic drugs (SANAD-II)

INTRODUCTION

Antiepileptic drugs (AEDs) are the mainstay of epilepsy treatment. Over the past 20 years, a number of new drugs have been approved for National Health Service (NHS) use on the basis of information from short-term trials that demonstrate efficacy. These trials do not provide information about the longer term outcomes, which inform treatment policy. This trial will assess the long-term clinical and cost-effectiveness of the newer treatment levetiracetam and zonisamide.

METHODS AND ANALYSIS

This is a phase IV, multicentre, open-label, randomised, controlled clinical trial comparing new and standard treatments for patients with newly diagnosed epilepsy. Arm A of the trial randomised 990 patients with focal epilepsy to standard AED lamotrigine or new AED levetiracetam or zonisamide. Arm B randomised 520 patients with generalised epilepsy to standard AED sodium valproate or new AED levetiracetam. Patients are recruited from UK NHS outpatient epilepsy, general neurology and paediatric clinics. Included patients are aged 5 years or older with two or more spontaneous seizures requiring AED monotherapy, who are not previously treated with AEDs. Patients are followed up for a minimum of 2 years. The primary outcome is time to 12-month remission from seizures. Secondary outcomes include time to treatment failure (including due to inadequate seizure control or unacceptable adverse reactions); time to first seizure; time to 24-month remission; adverse reactions and quality of life. All primary analyses will be on an intention to treat basis. Separate analyses will be undertaken for each arm. Health economic analysis will be conducted from the perspective of the NHS to assess the cost-effectiveness of each AED.

ETHICS AND DISSEMINATION

This trial has been approved by the North West-Liverpool East REC (Ref. 12/NW/0361). The trial team will disseminate the results through scientific meetings, peer-reviewed publications and patient and public involvement.

TRIAL REGISTRATION NUMBERS

EudraCT 2012-001884-64; ISRCTN30294119.

Investigating imaging network markers of cognitive dysfunction and pharmacoresistance in newly diagnosed epilepsy: a protocol for an observational cohort study in the UK

INTRODUCTION

Epilepsy is one of the most common serious brain disorders, characterised by seizures that severely affect a person's quality of life and, frequently, their cognitive and mental health. Although most existing work has examined chronic epilepsy, newly diagnosed patients present a unique opportunity to understand the underlying biology of epilepsy and predict effective treatment pathways. The objective of this prospective cohort study is to examine whether cognitive dysfunction is associated with measurable brain architectural and connectivity impairments at diagnosis and whether the outcome of antiepileptic drug treatment can be predicted using these measures.

METHODS AND ANALYSIS

107 patients with newly diagnosed focal epilepsy from two National Health Service Trusts and 48 healthy controls (aged 16-65 years) will be recruited over a period of 30 months. Baseline assessments will include neuropsychological evaluation, structural and functional Magnetic Resonance Imaging (MRI), Electroencephalography (EEG), and a blood and saliva sample. Patients will be followed up every 6 months for a 24-month period to assess treatment outcomes. Connectivity- and network-based analyses of EEG and MRI data will be carried out and examined in relation to neuropsychological evaluation and patient treatment outcomes. Patient outcomes will also be investigated with respect to analysis of molecular isoforms of high mobility group box-1 from blood and saliva samples.

ETHICS AND DISSEMINATION

This study was approved by the North West, Liverpool East Research Ethics Committee (19/NW/0384) through the Integrated Research Application System (Project ID 260623). Health Research Authority (HRA) approval was provided on 22 August 2019. The project is sponsored by the UoL (UoL001449) and funded by a UK Medical Research Council (MRC) research grant (MR/S00355X/1). Findings will be presented at national and international meetings and conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

IRAS Project ID 260623.

Protocol for the development of a core outcome set for cauda equina syndrome: systematic literature review, qualitative interviews, Delphi survey and consensus meeting

INTRODUCTION

Cauda equina syndrome (CES) is a serious neurological condition most commonly due to compression of the lumbosacral nerve roots, which can result in significant disability. The evidence for acute intervention in CES is mainly from retrospective studies. There is heterogeneity in the outcomes chosen for analysis in these studies, which makes it difficult to synthesise the data across studies. This study will develop a core outcome set for use in future studies of CES, engaging with key stakeholders and using transparent methodology. This will help ensure that relevant outcomes are used in future and will facilitate attempts to summarise data across studies in systematic reviews.

METHODS AND ANALYSIS

A systematic literature review will document all the outcomes for CES after surgery mentioned in the literature. The qualitative interviews with patients with CES will be semistructured, audio recorded, transcribed and thematically analysed with the use of NVivo V.10 to identify outcomes and determine the themes described. The outcomes from the literature review and patient interviews will be combined and prioritised to determine what the most important outcomes are in CES research studies to patients and healthcare professionals. The prioritisation will be done through a two-round iterative Delphi survey and a consensus meeting. This process will decide the core outcome set for patients with CES.

ETHICS AND DISSEMINATION

REC and HRA approval was obtained on the 6/12/16 for the qualitative interviews from South Central-Hampshire A REC. REC reference 16/SC/0587. REC and HRA approval was obtained on 26/3/18 for the Delphi process and consensus meeting from North West-Greater Manchester Central REC. REC reference was 18/NW/0022. The final core outcome set will be published and freely available.

TRIAL REGISTRATION NUMBER

This study is registered with the Core Outcome Measures in Effectiveness Trials database as study 824.

TM1-1 Seizure prophylaxis in gliomas (SPRING): a phase III randomised controlled trial comparing prophylactic levetiracetam versus no prophylactic anti-epileptic drug in glioma surgery

Objectives

There is no consensus regarding the need for prophylactic anti-epileptic drug (AED) in seizure-naive newly-diagnosed glioma patients. Data regarding prophylactic AED use are scant and inconclusive from older, small studies that enrolled patients with brain metastases, benign tumours and gliomas. A definitive randomised controlled trial (RCT) is needed to determine whether the policy of prophylactic AED therapy reduces the risk of first seizures in this population.

Design

Multi-centre RCT.

Subjects

Inclusion criteria: i. seizure-naive, ii. supratentorial glioma suitable for surgery (biopsy/resection), iii. age ≥16 years; iv. Karnofsky performance status >60.

Methods

Patients are randomised 1:1. Levetiracetam 500 mg bd for 2 weeks, increased to 750 mg bd thereafter for 1 year. Non-blinded. No placebo. Primary Outcome: one year risk of first seizure. Secondary outcomes: time to first seizure, time to first tonic-clonic seizure, mood, fatigue, quality of life, progression free survival, overall survival and incremental cost per QALY. Estimate of 1 year seizure rate in glioma after surgery is 20%. Based on a reduction in seizure rate to 10% a total of 806 patients will be recruited.

Results

Grant awarded by NIHR. Feasibility questionnaire demonstrated prophylactic AED rarely used. Neurosurgeons willing to randomise. 15 UK centres have expressed interest in participating.

Conclusions

SPRING will establish class I evidence for the use of seizure prophylaxis in glioma surgery. The trial will open to recruitment in January 2019.

A disease, disorder, illness or condition: How to label epilepsy?

The International League Against Epilepsy (ILAE) is an important source of guidance for health professionals when it comes to epilepsy. Their latest recommendation that epilepsy should no longer be called a “disorder,” but a “disease” has though caused controversy. The ILAE contends the change will improve epilepsy's image. Some clinicians and other organizations fear the change may not though be accepted by patients as in common parlance “disease” can be associated with “contagiousness”/”infection.” To allow practicing clinicians to make informed judgements about what language they use, we completed the first study to assess the preferences of those with epilepsy and significant others and explore if any of their characteristics were associated with preference. Via epilepsy interest groups and associations in England, Wales, Scotland and the Republic of Ireland, 971 patients and significant others were surveyed. Participants identified which of four labels for epilepsy (“disorder,” “illness,” “disease,” “condition”) they favoured and rated each using a Likert‐scale. Patients’ median age was 39; 69% had experienced seizures in the prior year. “Condition” was favoured by most patients (74.3%) and significant others (71.2%). Only 2.2% of patients and 1.2% of significant others chose “disease”; it received a median Likert‐rating indicating “strongly dislike.” Multinomial logistic regression found it was not possible to reliably distinguish between participants favouring the different terms on the basis of demographics. The ILAE's position is at odds with what most patients and carers want and we discuss the implications of this.

Risk of a seizure recurrence after a breakthrough seizure and the implications for driving: further analysis of the standard versus new antiepileptic drugs (SANAD) randomised controlled trial

OBJECTIVES

A breakthrough seizure is one occurring after at least 12 months seizure freedom while on treatment. The Driver and Vehicle Licensing Agency (DVLA) allows an individual to return to driving once they have been seizure free for 12 months following a breakthrough seizure. This is based on the assumption that the risk of a further seizure in the next 12 months has dropped <20%. This analysis considers whether the prescribed 1 year off driving following a breakthrough seizure is sufficient for this and stratifies risk according to clinical characteristics. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS AND MAIN OUTCOME MEASURES: The multicentre UK-based Standard versus New Antiepileptic Drugs (SANAD) study was a randomised controlled trial assessing standard and new antiepileptic drugs for patients with newly diagnosed epilepsy. For participants aged at least 16 with a breakthrough seizure, data have been analysed to estimate the annual seizure recurrence risk following a period of 6, 9 and 12 months seizure freedom. Regression modelling was used to investigate how antiepileptic drug treatment and a number of clinical factors influence the risk of seizure recurrence.

RESULTS

At 12 months following a breakthrough seizure, the overall unadjusted risk of a recurrence over the next 12 months is lower than 20%, risk 17% (95% CI 15% to 19%). However, some patient subgroups have been identified which have an annual recurrence risk significantly greater than 20% after an initial 12-month seizure-free period following a breakthrough seizure.

CONCLUSIONS

This reanalysis of SANAD provides estimates of seizure recurrence risks following a breakthrough seizure that will inform policy and guidance about regaining an ordinary driving licence. Further guidance is needed as to how such data should be used.

TRIAL REGISTRATION NUMBER

SANAD is registered with the International Standard Randomised Controlled Trial Number Register ISRCTN38354748.

Epilepsy and Pregnancy: For healthy pregnancies and happy outcomes. Suggestions for service improvements from the Multispecialty UK Epilepsy Mortality Group

Between 2009 and 2012 there were 26 epilepsy-related deaths in the UK of women who were pregnant or in the first post-partum year. The number of pregnancy-related deaths in women with epilepsy (WWE) has been increasing. Expert assessment suggests that most epilepsy-related deaths in pregnancy were preventable and attributable to poor seizure control. While prevention of seizures during pregnancy is important, a balance must be struck between seizure control and the teratogenic potential of antiepileptic drugs (AEDs). A range of professional guidance on the management of epilepsy in pregnancy has previously been issued, but little attention has been paid to how optimal care can be delivered to WWE by a range of healthcare professionals. We summarise the findings of a multidisciplinary meeting with representation from a wide group of professional bodies. This focussed on the implementation of optimal pregnancy epilepsy care aiming to reduce mortality of epilepsy in mothers and reduce morbidity in babies exposed to AEDs in utero. We identify in particular -What stage to intervene - Golden Moments of opportunities for improving outcomes -Which Key Groups have a role in making change -When - 2020 vision of what these improvements aim to achieve. -How to monitor the success in this field We believe that the service improvement ideas developed for the UK may provide a template for similar initiatives in other countries.

Epilepsy management in older people: Lessons from National Audit of Seizure management in Hospitals (NASH)

PURPOSE

Epilepsy is the third most common diagnosis in older people, however management in this group remains variable. National Audit of Seizure management in Hospitals (NASH) set out to assess care provided to patients attending hospitals in England following a seizure.

METHOD

154 Emergency Departments (EDs) across the UK took part. 1256 patients aged 60 years or over were included for analysis (median age 74 years, 54% men). 51% were known to have epilepsy, 17% had history of previous seizure or blackout and 32% presented with a suspected first seizure.

RESULTS

14% of older patients with epilepsy were not on treatment, 59% were on monotherapy. Sodium valproate was the most commonly used antiepileptic, 28%. 35% of patients with epilepsy, aged 60 and over, had a CT during admission compared to only 17% of those under 60. 80% of patients aged 60 and over presenting with a likely first seizure were admitted to hospital, compared to 65% of those under 60. 34% of those with suspected first seizure were referred to a neurologist on discharge compared to 68% of patients under the age of 60. 52% of 60-69year olds with a suspected first seizure were referred to neurology compared to 25% of patients aged 80-89.

CONCLUSIONS

Older patients presenting with seizures are more likely to be admitted to hospital and have imaging. They are less likely to be referred to specialist services on discharge. There appears to be significant disparity in patient age and rate of referral.

Molecular isoforms of high-mobility group box 1 are mechanistic biomarkers for epilepsy

Approximately 30% of epilepsy patients do not respond to antiepileptic drugs, representing an unmet medical need. There is evidence that neuroinflammation plays a pathogenic role in drug-resistant epilepsy. The high-mobility group box 1 (HMGB1)/TLR4 axis is a key initiator of neuroinflammation following epileptogenic injuries, and its activation contributes to seizure generation in animal models. However, further work is required to understand the role of HMGB1 and its isoforms in epileptogenesis and drug resistance. Using a combination of animal models and sera from clinically well-characterized patients, we have demonstrated that there are dynamic changes in HMGB1 isoforms in the brain and blood of animals undergoing epileptogenesis. The pathologic disulfide HMGB1 isoform progressively increased in blood before epilepsy onset and prospectively identified animals that developed the disease. Consistent with animal data, we observed early expression of disulfide HMGB1 in patients with newly diagnosed epilepsy, and its persistence was associated with subsequent seizures. In contrast with patients with well-controlled epilepsy, patients with chronic, drug-refractory epilepsy persistently expressed the acetylated, disulfide HMGB1 isoforms. Moreover, treatment of animals with antiinflammatory drugs during epileptogenesis prevented both disease progression and blood increase in HMGB1 isoforms. Our data suggest that HMGB1 isoforms are mechanistic biomarkers for epileptogenesis and drug-resistant epilepsy in humans, necessitating evaluation in larger-scale prospective studies.

A comparison of HMGB1 concentrations between cerebrospinal fluid and blood in patients with neurological disease

AIMS

To determine whether a correlation exists between paired cerebrospinal fluid (CSF) and serum levels of a novel inflammatory biomarker, high-mobility group box 1 (HMGB1), in different neurological conditions.

METHODS

HMGB1 was measured in the serum and CSF of 46 neurological patients (18 idiopathic intracranial hypertension [IIH], 18 neurological infection/inflammation [NII] and 10 Rasmussen's encephalitis [RE]).

RESULTS

Mean serum (± SD) HMGB1 levels were 1.43 ± 0.54, 25.28 ± 27.9 and 1.89 ± 1.49 ng/ml for the patients with IIH, NII and RE, respectively. Corresponding mean (± SD) CSF levels were 0.35 ± 0.22, 4.48 ± 6.56 and 2.24 ± 2.35 ng/ml. Both CSF and serum HMGB1 was elevated in NII. Elevated CSF HMGB1 was demonstrated in RE. There was no direct correlation between CSF and serum levels of HMGB1.

CONCLUSION

Serum HMGB1 cannot be used as a surrogate measure for CSF levels. CSF HMGB1 was elevated in NII and RE, its role as a prognostic/stratification biomarker needs further study.

Which outcomes should we measure in adult epilepsy trials? The views of people with epilepsy and informal carers

OBJECTIVE

So that informed treatment decisions can be made, clinical trials need to evaluate treatments against domains that are important to people with epilepsy (PWE), their carers, and clinicians. Health professionals have identified domains of importance to them via the International League Against Epilepsy's Commission on Outcome Measurement (COME). However, patients and carers have not been systematically asked.

METHODS

Via the membership of the British Epilepsy Association, we recruited and surveyed 352 PWE and 263 of their informal carers. They were presented with 10 outcome domains (including the 5 identified by COME) and asked to rate their importance using a 9-point Likert scale. They were also asked to identify any additional domains of importance.

RESULTS

The patients' mean age was 49years, the median number of years since diagnosis was 20, and 65% had experienced seizures in the prior 12months. Most carers were the spouse or parent. Patients' and carers' mean ratings indicated that their outcome priorities were similar, as were those of patients who had and had not experienced recent seizures. There was consensus among patients that 6 domains were of critical importance. These included the 5 identified by COME (namely, and in order of importance, the effects of the treatment on "Seizure severity", "Seizure frequency", "Quality of life", "Cognitive function", and "Adverse events"), as well as one additional domain ("Independence/need for support"). There was consensus among carers that the 5 COME domains were also critically important. They, however, identified 3 further domains as critically important. These were the effects of the treatment on patient "Depression", "Anxiety", and "Independence/need for support".

CONCLUSIONS

Our study found some overlap between the priorities of PWE, carers, and health professionals. They, however, highlight additional areas of importance to patients and carers. Our results could inform a core outcome set for epilepsy that represents the domains that should be reported as a minimum by all trials. This could promote trials which produce meaningful results and consistency in measurement and reporting.

'Seizure First Aid Training' for people with epilepsy who attend emergency departments, and their family and friends: study protocol for intervention development and a pilot randomised controlled trial

INTRODUCTION

People with chronic epilepsy (PWE) often make costly but clinically unnecessary emergency department (ED) visits. Offering them and their carers a self-management intervention that improves confidence and ability to manage seizures may lead to fewer visits. As no such intervention currently exists, we describe a project to develop and pilot one.

METHODS AND ANALYSIS

To develop the intervention, an existing group-based seizure management course that has been offered by the Epilepsy Society within the voluntary sector to a broader audience will be adapted. Feedback from PWE, carers and representatives from the main groups caring for PWE will help refine the course so that it addresses the needs of ED attendees. Its behaviour change potential will also be optimised. A pilot randomised controlled trial will then be completed. 80 PWE aged ≥16 who have visited the ED in the prior 12 months on ≥2 occasions, along with one of their family members or friends, will be recruited from three NHS EDs. Dyads will be randomised to receive the intervention or treatment as usual alone. The proposed primary outcome is ED use in the 12 months following randomisation. For the pilot, this will be measured using routine hospital data. Secondary outcomes will be measured by patients and carers completing questionnaires 3, 6 and 12 months postrandomisation. Rates of recruitment, retention and unblinding will be calculated, along with the ED event rate in the control group and an estimate of the intervention's effect on the outcome measures.

ETHICS AND DISSEMINATION

Ethical approval: NRES Committee North West-Liverpool East (Reference number 15/NW/0225). The project's findings will provide robust evidence on the acceptability of seizure management training and on the optimal design of a future definitive trial. The findings will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

ISRCTN13 871 327.

Personalized medicine approaches in epilepsy

Epilepsy affects 50 million persons worldwide, a third of whom continue to experience debilitating seizures despite optimum anti-epileptic drug (AED) treatment. Twelve-month remission from seizures is less likely in female patients, individuals aged 11-36 years and those with neurological insults and shorter time between first seizure and starting treatment. It has been found that the presence of multiple seizures prior to diagnosis is a risk factor for pharmacoresistance and is correlated with epilepsy type as well as intrinsic severity. The key role of neuroinflammation in the pathophysiology of resistant epilepsy is becoming clear. Our work in this area suggests that high-mobility group box 1 isoforms may be candidate biomarkers for treatment stratification and novel drug targets in epilepsy. Furthermore, transporter polymorphisms contributing to the intrinsic severity of epilepsy are providing robust neurobiological evidence on an emerging theory of drug resistance, which may also provide new insights into disease stratification. Some of the rare genetic epilepsies enable treatment stratification through testing for the causal mutation, for example SCN1A mutations in patients with Dravet's syndrome. Up to 50% of patients develop adverse reactions to AEDs which in turn affects tolerability and compliance. Immune-mediated hypersensitivity reactions to AED therapy, such as toxic epidermal necrolysis, are the most serious adverse reactions and have been associated with polymorphisms in the human leucocyte antigen (HLA) complex. Pharmacogenetic screening for HLA-B*15:02 in Asian populations can prevent carbamazepine-induced Stevens-Johnson syndrome. We have identified HLA-A*31:01 as a potential risk marker for all phenotypes of carbamazepine-induced hypersensitivity with applicability in European and other populations. In this review, we explore the currently available key stratification approaches to address the therapeutic challenges in epilepsy.

Exploring the genomic basis of pharmacoresistance in epilepsy: an integrative analysis of large-scale gene expression profiling studies on brain tissue from epilepsy surgery

Some patients with pharmacoresistant epilepsy undergo therapeutic resection of the epileptic focus. At least 12 large-scale microarray studies on brain tissue from epilepsy surgery have been published over the last 10 years, but they have failed to make a significant impact upon our understanding of pharmacoresistance, because (1) doubts have been raised about their reproducibility, (2) only a small number of the gene expression changes found in each microarray study have been independently validated and (3) the results of different studies have not been integrated to give a coherent picture of the genetic changes involved in epilepsy pharmacoresistance. To overcome these limitations, we (1) assessed the reproducibility of the microarray studies by calculating the overlap between lists of differentially regulated genes from pairs of microarray studies and determining if this was greater than would be expected by chance alone, (2) used an inter-study cross-validation technique to simultaneously verify the expression changes of large numbers of genes and (3) used the combined results of the different microarray studies to perform an integrative analysis based on enriched gene ontology terms, networks and pathways. Using this approach, we respectively (1) demonstrate that there are statistically significant overlaps between the gene expression changes in different publications, (2) verify the differential expression of 233 genes and (3) identify the biological processes, networks and genes likely to be most important in the development of pharmacoresistant epilepsy. Our analysis provides novel biologically plausible candidate genes and pathways which warrant further investigation to assess their causal relevance.

Adverse antiepileptic drug effects in new-onset seizures: a case-control study

OBJECTIVE

Adverse effects (AEs) are a major concern when starting antiepileptic drug (AED) treatment. This study quantified the extent to which AE reporting in people with new-onset seizures started on AEDs is attributable to the medication per se, and investigated variables contributing to AE reporting.

METHODS

We pooled data from 2 large prospective studies, the Multicenter Study of Early Epilepsy and Single Seizures and the Northern Manhattan Study of incident unprovoked seizures, and compared adverse event profile (AEP) total and factor scores between adult cases prescribed AEDs for new-onset seizures and untreated controls, adjusting for several demographic and clinical variables. Differences in AEP scores were also tested across different AED monotherapies and controls, and between cases and controls grouped by number of seizures.

RESULTS

A total of 212 cases and 206 controls were identified. Most cases (94.2%) were taking low AED doses. AEP scores did not differ significantly between the 2 groups. Depression, female gender, symptomatic etiology, younger seizure onset age, ≥2 seizures, and history of febrile seizures were associated with higher AEP scores. There were no significant differences in AEP scores across different monotherapies and controls. AEP scores increased in both cases and controls with increasing number of seizures, the increment being more pronounced in cases.

CONCLUSIONS

When AED treatment is started at low doses following new-onset seizures, AE reporting does not differ from untreated individuals. Targeting specific factors affecting AE reporting could lead to improved tolerability of epilepsy treatment.

Risk of recurrence after a first seizure and implications for driving: further analysis of the Multicentre study of early Epilepsy and Single Seizures

OBJECTIVE

To determine for how long after a first unprovoked seizure a driver must be seizure-free before the risk of recurrence in the next 12 months falls below 20%, enabling them to regain their driving licence.

DESIGN

Randomised controlled trial: Multicentre study of early Epilepsy and Single Seizures (MESS).

SETTING

UK hospital outpatient clinics from 1 January 1993 to 31 December 2000.

PARTICIPANTS

People entered MESS if they had had one or more unprovoked seizures and both the participant and the clinician were uncertain about the need to start antiepileptic drug treatment. The subset of people used for this analysis comprised participants aged at least 16 years with a single unprovoked seizure.

MAIN OUTCOME MEASURE

Risk of seizure recurrence in the 12 months after a seizure-free period of 6, 12, 18, or 24 months from the date of the first (index) seizure. Regression modelling was used to investigate how antiepileptic treatment and several clinical factors influence the risk of seizure recurrence.

RESULTS

At six months after the index seizure the risk of recurrence in the next 12 months for those who start antiepileptic drugs was significantly below 20% (unadjusted risk 14%, 95% confidence interval 10% to 18%). For patients who did not start treatment the risk estimate was less than 20% but the upper limit of the confidence interval was greater than 20% (18%, 13% to 23%). Multivariable analyses identified subgroups with a significantly greater than 20% risk of seizure recurrence in the 12 months after a six month seizure-free period, such as those with a remote symptomatic seizure with abnormal electroencephalogram results.

CONCLUSION

After a single unprovoked seizure this reanalysis of MESS provides estimates of seizure recurrence risks that will inform policy and guidance about regaining an ordinary driving licence. Further guidance is needed as to how such data should be utilised; in particular, whether a population approach should be taken with a focus on the unadjusted results or whether attempts should be made to individualise risk. Guidance is also required as to whether the focus should be on risk estimates only or on the confidence interval as well. If the focus is on the estimate only our unadjusted estimates suggest that treated and untreated patients are eligible to drive after being seizure-free for six months. If the focus is also on confidence intervals, direction is needed as to whether a conservative or liberal approach should be taken.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN98767960.

Meta-regression with partial information on summary trial or patient characteristics

We present a model for meta-regression in the presence of missing information on some of the study level covariates, obtaining inferences using Bayesian methods. In practice, when confronted with missing covariate data in a meta-regression, it is common to carry out a complete case or available case analysis. We propose to use the full observed data, modelling the joint density as a factorization of a meta-regression model and a conditional factorization of the density for the covariates. With the inclusion of several covariates, inter-relations between these covariates are modelled. Under this joint likelihood-based approach, it is shown that the lesser assumption of the covariates being Missing At Random is imposed, instead of the more usual Missing Completely At Random (MCAR) assumption. The model is easily programmable in WinBUGS, and we examine, through the analysis of two real data sets, sensitivity and robustness of results to the MCAR assumption.

Consensus guidelines into the management of epilepsy in adults with an intellectual disability

BACKGROUND

Epilepsy has a pervasive impact on the lives of people with intellectual disability and their carers. The delivery of high-quality care is impacted on by the complexity and diversity of epilepsy in this population. This article presents the results of a consensus clinical guideline process.

RESULTS

A Delphi process identified a list of priority areas for the development of evidence-based guidelines. All guidelines were graded and consensus on scoring was achieved across the guideline group.

CONCLUSION

There is a dearth of high-quality evidence from well-constructed studies on which to base guidance. However, the development of internationally derived consensus guidelines may further support the management of epilepsy in adults with an intellectual disability.

Joint modelling of longitudinal and competing risks data

Available methods for joint modelling of longitudinal and survival data typically have only one failure type for the time to event outcome. We extend the methodology to allow for competing risks data. We fit a cause-specific hazards sub-model to allow for competing risks, with a separate latent association between longitudinal measurements and each cause of failure.The method is applied to data from the SANAD trial of anti-epileptic drugs (AEDs), as a means of investigating the effect of drug titration on the relative effects of lamotrigine (LTG) and carbamazepine (CBZ) on treatment failure. Concern had been expressed that differential titration rates may have been to the disadvantage of CBZ. The beneficial effect of LTG on unacceptable adverse events leading to drug withdrawal did not lessen and indeed increased slightly when a calibrated dose was accounted for in the joint model. Adjustment for the titration rate of LTG relative to CBZ resulted in an unchanged effect of the former on drug withdrawals due to inadequate seizure control. LTG remains the AED of choice from this analysis.

Clobazam as an add-on in the management of refractory epilepsy

BACKGROUND

Epilepsy effects approximately 1% of the population, with up to 30% of patients continuing to have seizures despite antiepileptic drug treatment.

OBJECTIVES

To assess the efficacy and tolerability of clobazam when used as an add-on therapy for patients with refractory partial onset or generalised onset seizures.

SEARCH STRATEGY

We searched the following on 22nd March 2007: (a) The Cochrane Epilepsy Group Specialised Register; (b) The Cochrane Central Register of Controlled Trials (CENTRAL); (c) MEDLINE; (d) EMBASE; (e) Database of Abstracts of Reviews of Effectiveness (DARE); (f) American College of Physicians Journals; (g) BIOSIS.

SELECTION CRITERIA

Randomised trials of add-on clobazam, with adequate methods of allocation concealment, recruiting patients with drug refractory partial or generalised onset seizures, with a minimum treatment period of eight weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted relevant data. The following outcomes were assessed: 50% or greater reduction in seizures; seizure freedom; treatment withdrawal and adverse effects.

MAIN RESULTS

Four cross-over studies, representing 196 participants, were included. However, due to significant methodological heterogeneity and differences in outcome measures it was not possible to summarise data in a meta-analysis. Only two of the studies reported a 50% or greater seizure reduction compared to placebo; 57.7% and 52.4%. Side effects were only described in two of the studies, reportedly present in 36% and 85% of patients.

AUTHORS' CONCLUSIONS

Clobazam as an add-on treatment may reduce seizure frequency and may be most effective in partial onset seizures. However, it is not clear who will best benefit and over what time-frame. A large scale, randomised controlled trial conducted over a greater period of time, incorporating subgroups with differing seizure types, is required to inform clinical practice.

Pregabalin add-on for drug-resistant partial epilepsy

BACKGROUND

Epilepsy is a common chronic neurological disease with an estimated prevalence of 1% in the United Kingdom. Approximately a third of these people continue to have seizures despite drug treatment. In order to try to improve outcomes a number of new antiepileptic drugs have been developed and pregabalin is one of these.

OBJECTIVES

To summarize evidence from randomized, controlled trials regarding the efficacy and tolerability of pregabalin when used as an add-on antiepileptic drug in treatment-resistant partial epilepsy.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group Specialized Register (July 2007), The Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2007), Medline (1966 to March 2007) and contacted Pfizer Inc (the manufacturers of pregabalin) to identify published, unpublished, and ongoing trials.

SELECTION CRITERIA

We included randomized controlled double-blind trials comparing pregabalin with placebo for people with drug-refractory partial epilepsy. Outcomes included 50% or greater reduction in seizure frequency, treatment withdrawal for any reason, treatment withdrawal for adverse events, and nature of adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors (DL and AGM) independently selected and assessed suitable trials and extracted data. Primary analyses were by intention-to-treat (ITT). Results are presented as relative risks (RR) with 95% confidence intervals (CI).

MAIN RESULTS

Four suitable trials (1397 participants) were identified and included in the analysis. Trials tested doses of pregabalin ranging from 50 mg to 600 mg per day. For the primary outcome, 50% or higher seizure reduction was significantly more likely in patients randomized to pregabalin than to placebo (RR 3.56, 95% CI 2.60 to 4.87). A dose response analysis suggested increasing effect with increasing dose. Pregabalin was not significantly associated with seizure freedom (RR 2.73, 95% CI 0.72 to 10.33). Patients were significantly more likely to have pregabalin withdrawn for any reason (RR 1.43, 95% CI 1.11 to 1.85) or for adverse effects (RR 2.47, 95% CI 1.80 to 4.17). Ataxia, dizziness, somnolence and weight gain were significantly associated with pregabalin.

AUTHORS' CONCLUSIONS

Pregabalin, when used as an add-on drug for treatment-resistant partial epilepsy, is significantly more effective than placebo at achieving a 50% or greater seizure reduction. Results demonstrate efficacy for doses from 150 mg to 600 mg per day, with no evidence for plateauing of effect at the doses tested. The trials included in this review were of short duration and longer term trials are needed to better inform clinical decision making.

Non-pharmacological interventions for epilepsy in people with intellectual disabilities

BACKGROUND

Approximately 30% of epilepsy patients remain refractory to drug treatment and continue to experience seizures whilst taking one or more antiepileptic drugs. There are a number of non-pharmacological interventions available to refractory patients which may be used in conjunction with or as an alternative to antiepileptic medication. In view of the fact that seizures in intellectually disabled people are often complex and refractory to pharmacological interventions it is evident that good quality randomised controlled trials (RCTs) assessing the efficacy of alternatives or adjuncts to pharmacological interventions are needed in this population.

OBJECTIVES

The aim of our study was to assess the data available from randomised controlled trials of non-pharmacological interventions in patients with epilepsy and intellectual disabilities.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2006), MEDLINE OVID (1966 to October 2006) and PsychInfo OVID (1806 to October 2006).

SELECTION CRITERIA

Randomised controlled trials of non-pharmacological interventions for people with epilepsy and intellectual disabilities

DATA COLLECTION AND ANALYSIS

Two review authors independently applied inclusion criteria and extracted data.

MAIN RESULTS

No RCTs were found for this study population.

AUTHORS' CONCLUSIONS

This review has highlighted the need for well-designed randomised controlled trials to assess the effect of non-pharmacological interventions on seizure and behavioural outcomes in an intellectually disabled epilepsy population.

A randomised controlled trial examining the longer-term outcomes of standard versus new antiepileptic drugs. The SANAD trial

OBJECTIVES

To compare clinicians' choice of one of the standard epilepsy drug treatments (carbamazepine or valproate) versus appropriate comparator new drugs.

DESIGN

A clinical trial comprising two arms, one comparing new drugs in carbamazepine and the other with valproate.

SETTING

A multicentre study recruiting patients with epilepsy from hospital outpatient clinics.

PARTICIPANTS

Patients with an adequately documented history of two or more clinically definite unprovoked epileptic seizures within the last year for whom treatment with a single antiepileptic drug represented the best therapeutic option.

INTERVENTIONS

Arm A was carbamazepine (CBZ) versus gabapentin (GBP) versus lamotrigine (LTG) versus oxcarbazepine (OXC) versus topiramate (TPM). Arm B valproate (VPS) versus LTG versus TPM.

MAIN OUTCOME MEASURES

Time to treatment failure (withdrawal of the randomised drug for reasons of unacceptable adverse events or inadequate seizure control or a combination of the two) and time to achieve a 12-month remission of seizures. Time from randomisation to first seizure, 24-month remission of seizures, incidence of clinically important adverse events, quality of life (QoL) outcomes and health economic outcomes were also considered.

RESULTS

Arm A recruited 1721 patients (88% with symptomatic or cryptogenic partial epilepsy and 10% with unclassified epilepsy). Arm B recruited 716 patients (63% with idiopathic generalised epilepsy and 25% with unclassified epilepsy). In Arm A LTG had the lowest incidence of treatment failure and was statistically superior to all drugs for this outcome with the exception of OXC. Some 12% and 8% fewer patients experienced treatment failure on LTG than CBZ, the standard drug, at 1 and 2 years after randomisation, respectively. The superiority of LTG over CBZ was due to its better tolerability but there is satisfactory evidence indicating that LTG is not clinically inferior to CBZ for measures of its efficacy. No consistent differences in QoL outcomes were found between treatment groups. Health economic analysis supported LTG being preferred to CBZ for both cost per seizure avoided and cost per quality-adjusted life-year gained. In Arm B for time to treatment failure, VPS, the standard drug, was preferred to both TPM and LTG, as it was the drug least likely to be associated with treatment failure for inadequate seizure control and was the preferred drug for time to achieving a 12-month remission. QoL assessments did not show any between-treatment differences. The health economic assessment supported the conclusion that VPS should remain the drug of first choice for idiopathic generalised or unclassified epilepsy, although there is a suggestion that TPM is a cost-effective alternative to VPS.

CONCLUSIONS

The evidence suggests that LTG may be a clinical and cost-effective alternative to the existing standard drug treatment, CBZ, for patients diagnosed as having partial seizures. For patients with idiopathic generalised epilepsy or difficult to classify epilepsy, VPS remains the clinically most effective drug, although TPM may be a cost-effective alternative for some patients. Three new antiepileptic drugs have recently been licensed in the UK for the treatment of epilepsy (levetiracetam, zonisamide and pregabalin), therefore these drugs should be compared in a similarly designed trial.

Pharmacological interventions for epilepsy in people with intellectual disabilities

BACKGROUND

The development of epilepsy in a person with intellectual disabilities is a common occurrence. In view of the fact that seizures in intellectually disabled people are often complex and refractory to treatment and that antiepileptic medication may have a profound effect upon behaviour in this patient group, it is evident that good quality randomised controlled trials are needed in this population.

OBJECTIVES

The aim of our study was to assess the data available from randomised controlled trials of antiepileptic drug interventions in people with epilepsy and intellectual disabilities.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2006, Issue 4), MEDLINE OVID (1966 to October 2006), PsychInfo OVID (1806 to October 2006) and EMBASE OVID (1980 to April 2005).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of pharmacological interventions for people with epilepsy and a learning disability. RCTs where inadequate methods of allocation concealment had been used were also included.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. Outcome measures included the following.(1) Retention on treatment.(2) Seizure freedom.(3) Reduction in seizure frequency.(4) Seizure severity scales.(5) Global rating scales.(6) Behavioural outcomes.(7) Cognitive outcomes.(8) Adverse effects.(9) Quality of life.

MAIN RESULTS

Data were heterogenous and a descriptive analysis is presented. This review confirms that in the majority of cases where antiepileptic drugs (AEDs) were trialled in this population, moderate reduction in seizure frequency and occasional seizure freedom were obtained. In general it seems reasonable to say that AEDs proven effective in the general epilepsy population are also effective in refractory epilepsy in people with intellectual disability. It is not possible to comment on relative efficacy between medications making clinical choice decisions difficult. Clinical decision is also likely to be guided by concern over side effects. The quality of the studies does not aid clinicians greatly to this respect. In general it seems that in trial settings patients continue on treatment, in the majority of cases, and placebo groups often experience less in the way of side effects. Where side effects are experienced they appear similar to those seen in non-intellectual disability studies. One area of key concern is that of behavioural exacerbation. The majority of studies are unhelpful due to lack of or non-reliable measures in this area. However, where measured, little obvious impact on behaviour is seen in terms of behaviour disorder.

AUTHORS' CONCLUSIONS

In summary this review broadly supports the use of AEDs to reduce seizure frequency in people with refractory epilepsy and intellectual disability. The evidence suggests that side effects are similar to those in the general population and that behavioural side effects leading to discontinuation are rare but that other effects are under researched.

Efficacy of carbamazepine and valproate as monotherapy for early epilepsy and single seizures

In the Multi-Centre Study of Early Epilepsy and Single Seizures (MESS), patients were randomly allocated to immediate or delayed antiepileptic drug treatment. For time to first seizure recurrence, MESS provides strong evidence of an effect for carbamazepine as monotherapy but mixed evidence of an effect for valproate.

A meta-analysis of individual patient responses to lamotrigine or carbamazepine monotherapy

OBJECTIVE

To compare the effects of carbamazepine and lamotrigine monotherapy for people with partial onset seizures or generalized onset tonic-clonic seizures.

METHODS

A systematic review and meta-analysis using data on individual patients from randomized trials comparing lamotrigine with carbamazepine monotherapy. The review draws on the search strategy developed for the Cochrane Epilepsy Group, which searches MEDLINE and the Cochrane Controlled Trials register, and hand searches relevant journals. The outcomes considered were time to antiepileptic drug withdrawal, which would usually be for either inadequate seizure control or unacceptable adverse effects, time to first seizure, and 6-month remission.

RESULTS

Five randomized trials were identified containing data for 1,384 participants. Time to treatment withdrawal significantly improved with lamotrigine compared to carbamazepine (hazard ratio 0.55, 95% CI 0.35 to 0.84, random effects), while time to first seizure (hazard ratio 1.14, 95% CI 0.92 to 1.43, fixed effects) and seizure freedom at 6 months (relative risk 0.92, 95% CI 0.81 to 1.04, fixed effects) favor carbamazepine although the results are not significant.

CONCLUSIONS

Lamotrigine is significantly less likely to be withdrawn than carbamazepine, but results for time to first seizure suggest a nonsignificant trend that carbamazepine may be superior in terms of seizure control. Trials were of too short a duration to measure clinically important efficacy outcomes such as time to 12-month remission. Current industry-sponsored trials fail to adequately inform clinical practice and further more clinically relevant trials are needed in which longer-term outcomes are assessed before the place of lamotrigine in the treatment of epilepsy is defined.

Oxcarbazepine versus phenytoin monotherapy for epilepsy

BACKGROUND

Worldwide, phenytoin is a commonly used antiepileptic drug. Oxcarbazepine is one of the newer antiepileptic drugs and has similar chemical properties to its parent compound carbamazepine. For the new drugs such as oxcarbazepine, it is important to know how they compare with standard treatments.

OBJECTIVES

To review the best evidence comparing oxcarbazepine and phenytoin when used as monotherapy in patients with epilepsy.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group's Specialized Register (December 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2005), and MEDLINE (1966 to November 2005). No language restrictions were imposed. We checked the reference lists of retrieved studies for additional reports of relevant studies. We also contacted pharmaceutical companies to try and identify any unpublished studies.

SELECTION CRITERIA

Randomized controlled trials in children or adults with epilepsy. Trials must have included a comparison of oxcarbazepine monotherapy with phenytoin monotherapy.

DATA COLLECTION AND ANALYSIS

This was an individual patient data review. Two review authors independently assessed trial quality and extracted data. Study authors were contacted for additional information. Outcomes were (a) time on allocated treatment; (b) time to achieve 6, 12 and 24-month remission; (c) time to first seizure post randomization; (d) quality of life measures if available. Clinical heterogeneity was assessed by reviewing differences across trials in characteristics of randomized patients, dosing protocols and trial design. Data were analysed on an intention to treat basis. Stratified logrank tests were used to obtain study-specific and overall estimates of hazard ratios (with 95% confidence intervals), where a HR > 1 indicates that an event is more likely on phenytoin.

MAIN RESULTS

Individual patient data were available for 480 patients from two trials, representing 100% of the patients recruited into the two trials that met our inclusion criteria. By convention, for the outcomes time to withdrawal of allocated treatment and time to first seizure a hazards ratio (HR) > 1 indicates a clinical advantage for oxcarbazepine and for time to 6 and 12-month remission a HR > 1 indicates a clinical advantage for phenytoin. The main overall results (HR, 95% confidence interval (CI)) were: (i) time to withdrawal of allocated treatment 1.64 (1.09 to 2.47), (ii) time to 6-month remission 0.89 (0.66 to 1.22), (iii) time to 12-month remission 0.92 (0.62 to 1.37), (iv) time to first seizure 1.07 (0.83 to 1.39). The overall results indicate that oxcarbazepine is significantly better than phenytoin for time to treatment withdrawal, but suggest no overall difference between oxcarbazepine and phenytoin for other outcomes. Results stratified by seizure type indicate no significant advantage for either drug for patients with generalized onset seizures, but a potentially important advantage in time to withdrawal for oxcarbazepine for patients with partial onset seizures: HR 1.92 (95% CI 1.17 to 3.16). The age distribution of adults classified as having generalized epilepsy suggests a significant number of patients may have had their epilepsy misclassified.

AUTHORS' CONCLUSIONS

For patients with partial onset seizures oxcarbazepine is significantly less likely to be withdrawn, but current data do not allow a statement as to whether oxcarbazepine is equivalent, superior or inferior to phenytoin in terms of seizure control. Guidelines recommend carbamazepine as a first line treatment for patients with partial onset seizures and more evidence is needed regarding the comparative effects of oxcarbazepine and carbamazepine to further inform policy. For patients with generalized onset tonic-clonic seizures, valproate is considered the first line standard treatment and the results of this review do not inform current treatment policy. Misclassification of patients' epilepsy type may have confounded the results of this review.

Lamotrigine versus carbamazepine monotherapy for epilepsy

BACKGROUND

The choice of an antiepileptic drug (AED) for any individual should take into account reliable information about seizure control, adverse effects and cost. Carbamazepine is the usual drug of choice for people with newly-diagnosed partial onset seizures. Lamotrigine is a relatively new AED which is licensed in many countries for use as an initial monotherapy.

OBJECTIVES

To review the best evidence comparing carbamazepine and lamotrigine when used as monotherapy in people with partial onset seizures, or generalized onset tonic-clonic seizures with or without other generalized seizure types.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group's Specialized Register (July 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) (TheCochraneLibrary Issue 2, 2005), and MEDLINE (1966 to August 2005). No language restrictions were imposed. We also contacted pharmaceutical companies and trial investigators.

SELECTION CRITERIA

Randomized controlled trials, blinded or unblinded, in which children or adults with partial onset seizures or generalized onset tonic-clonic seizures were randomized to monotherapy with either carbamazepine or lamotrigine.

DATA COLLECTION AND ANALYSIS

This was an individual patient data review. Outcomes were (1) time to treatment withdrawal, (2) time to first seizure post randomization, and (3) seizure freedom at six months. Time to event data were analysed using a stratified logrank analysis with results expressed as hazard ratios (HR) and 95% confidence intervals (95% CI); binary data were expressed as relative risks (RR) and 95% confidence intervals (95% CI). A HR or a RR greater than 1 indicated an event was more likely on lamotrigine than carbamazepine.

MAIN RESULTS

Individual patient data were available for 1384 participants (100% of total randomized) from the five trials that met our inclusion criteria. The main results (HR (95% CI)) were (1) time to treatment withdrawal 0.55 (0.35 to 0.84) (random-effects), (2) time to first seizure post randomization 1.14 (95% CI 0.92 to 1.43), and (3) seizure freedom at six months RR 0.92 (95% CI 0.81 to 1.04). The review suggested that time to treatment withdrawal was significantly improved with lamotrigine compared to carbamazepine, while time to first seizure and seizure freedom at six months favoured carbamazepine although the results were not statistically significant.

AUTHORS' CONCLUSIONS

Lamotrigine was significantly less likely to be withdrawn than carbamazepine but results for time to first seizure suggested that carbamazepine may be superior in terms of seizure control. Trials were of too short a duration to measure important seizure outcomes such as time to 12 month remission. Further trials are needed in which longer-term outcome is assessed as well as measures such as psychosocial outcome and quality of life.

Zonisamide add-on for drug-resistant partial epilepsy

BACKGROUND

The majority of people with epilepsy have a good prognosis and their seizures can be well controlled with the use of a single antiepileptic agent, but up to 30% develop refractory epilepsy, especially those with partial seizures. In this review we summarize the current evidence regarding zonisamide, when used as an add-on treatment for drug-resistant partial epilepsy.

OBJECTIVES

To evaluate the effects of zonisamide when used as an add-on treatment for people with drug-resistant partial epilepsy.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group Specialized Register (August 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2005). In addition, we contacted Eisai Limited (makers and licensees of zonisamide) and experts in the field to seek any ongoing/unpublished studies.

SELECTION CRITERIA

Randomized placebo controlled add-on trials of zonisamide in people with drug-resistant partial epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted data. Outcomes were: (1) 50% or greater reduction in total seizure frequency; (2) treatment withdrawal; (3) adverse events. Primary analyses were intention-to-treat. Summary relative risks (RRs) were estimated for each outcome.

MAIN RESULTS

Four trials (850 participants) were included. The overall RR with 95% confidence intervals (CIs) for 50% reduction in seizure frequency compared to placebo for 300 to 500 mg/day of zonisamide was 2.44 (95% CI 1.81 to 3.30). The RR for any dose zonisamide (100 to 500 mg per day) was 2.35 (1.74 to 3.17). Two trials provide evidence of a dose response relationship for this outcome. The RR for treatment withdrawal for 300 to 500 mg/day zonisamide compared to placebo was 1.64 (1.20 to 2.26), and for 100 to 500 mg per day was 1.47 (1.07 to 2.02). The CIs of the following adverse effects indicate that they are significantly associated with zonisamide: ataxia 4.50 (99% CI 1.05 to 19.22); dizziness 1.77 (99% CI 1.00 to 3.12); somnolence 1.96 (99% CI 1.12 to 3.44); agitation 2.37 (99% CI 1.00 to 5.64); and anorexia 3.00 (99% CI 1.31 to 6.88).

AUTHORS' CONCLUSIONS

Zonisamide has efficacy as an add-on treatment in people with drug-resistant partial epilepsy. Minimum effective and maximum tolerated doses cannot be identified. The trials reviewed were of 12 week duration and results cannot be used to confirm longer periods of effectiveness in seizure control. The results cannot be extrapolated to monotherapy or to people with other seizure types or epilepsy syndromes.

Ethosuximide, sodium valproate or lamotrigine for absence seizures in children and adolescents

BACKGROUND

Absence seizures are brief epileptic seizures which present in childhood and adolescence. They are characterised by sudden loss of awareness and an electroencephalogram (EEG) typically shows generalised spike wave discharges at three cycles per second. Ethosuximide, valproate and lamotrigine are currently used to treat absence seizures. This review aims to determine the best choice of anticonvulsant for a child with typical absence seizures.

OBJECTIVES

To review the evidence for the effects of ethosuximide, valproate and lamotrigine as treatments for children and adolescents with absence seizures, when compared with placebo or each other.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group's Specialised Register (March 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2005), MEDLINE (1966 to March 2005) and EMBASE (1988 to March 2005). No language restrictions were imposed. In addition, we contacted Sanofi Winthrop, Glaxo Wellcome (now GlaxoSmithKline) and Parke Davis (now Pfizer), manufacturers of sodium valproate, lamotrigine and ethosuximide respectively.

SELECTION CRITERIA

Randomised parallel group monotherapy or add-on trials which include a comparison of any of the following in children or adolescents with absence seizures: ethosuximide; sodium valproate; lamotrigine or placebo.

DATA COLLECTION AND ANALYSIS

Outcome measures were: (1) proportion of individuals seizure free at 1, 3, 6, 12 and 18 months post randomisation; (2) people with a 50% or greater reduction in seizure frequency; (3) normalisation of EEG and/or negative hyperventilation test and (4) adverse effects. Data were independently extracted by two review authors. Results are presented as relative risks (RR) with 95% confidence intervals (95% CI).

MAIN RESULTS

Five small trials were found, four of them were of poor methodological quality. One trial (29 participants) compared lamotrigine with placebo using a response conditional design. Individuals taking lamotrigine were significantly more likely to be seizure free than participants taking placebo during this short trial. Another trial compared lamotrigine with sodium valproate, the study lacked power to detect the difference in efficacy. Three studies compared ethosuximide, but because of diverse study designs and populations studied, we decided not to pool results in a meta-analysis. None of these studies found a difference between valproate and ethosuximide with respect to seizure control, but confidence intervals were wide and the existence of important differences could not be excluded.

AUTHORS' CONCLUSIONS

Although ethosuximide, lamotrigine and valproate are commonly used to treat people with absence seizures we have insufficient evidence to inform clinical practice, and the few trials included in this review were of poor methodological quality and did not have sufficient number of participants. More trials of better quality are needed.

Ethosuximide, sodium valproate or lamotrigine for absence seizures in children and adolescents

BACKGROUND

Absence seizures are brief epileptic seizures which present in childhood and adolescence. They are characterised by sudden loss of awareness and an electroencephalogram (EEG) typically shows generalised spike wave discharges at three cycles per second. Ethosuximide, valproate and lamotrigine are currently used to treat absence seizures. This review aims to determine the best choice of anticonvulsant for a child with typical absence seizures.

OBJECTIVES

To review the evidence for the effects of ethosuximide, valproate and lamotrigine as treatments for children and adolescents with absence seizures, when compared with placebo or each other.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group trials register, the Cochrane Central Register of Controlled Trials (The Cochrane Library issue 1, 2003), MEDLINE (January 1966 to March 2003) and EMBASE (1988 to March 2003). We also contacted Sanofi Winthrop, Glaxo Wellcome (now GlaxoSmithKline) and Parke Davis (now Pfizer), manufacturers of sodium valproate, lamotrigine and ethosuximide respectively.

SELECTION CRITERIA

Randomised parallel group monotherapy or add-on trials which include a comparison of any of the following in children or adolescents with absence seizures: ethosuximide; sodium valproate; lamotrigine or placebo.

DATA COLLECTION AND ANALYSIS

Outcome measures were: (i) proportion of individuals seizure free at 1, 6 and 18 months post randomisation; (ii) people with a 50% or greater reduction in seizure frequency; (iii) normalisation of EEG and/or negative hyperventilation test and (iv) adverse effects. Data were independently extracted by two reviewers. Results are presented as relative risks (RR) with 95% confidence intervals (95% CI).

MAIN RESULTS

Four small trials were found, which were of poor methodological quality. One trial (29 participants) compared lamotrigine with placebo using a response conditional design. Individuals taking lamotrigine were significantly more likely to be seizure free than participants taking placebo during this short trial. Three studies compared ethosuximide, but because of diverse study designs and populations studied, we decided not to pool results in a meta-analysis. None of these studies found a difference between valproate and ethosuximide with respect to seizure control, but confidence intervals were wide and the existence of important differences could not be excluded.

REVIEWER'S CONCLUSIONS

Although ethosuximide, lamotrigine and valproate are commonly used to treat people with absence seizures we have insufficient evidence to inform clinical practice, and the few trials included in this review were of poor methodological quality. More trials of better quality are needed.

Carbamazepine versus phenobarbitone monotherapy for epilepsy

BACKGROUND

In developing countries, phenobarbitone is commonly used but its use in Europe and the USA has decreased due to concerns over adverse effects. Carbamazepine is recommended as the drug of choice for partial onset seizures, and there is concern that it may worsen some generalized onset seizure types. We report a review using individual patient data in which carbamazepine and phenobarbitone are compared.

OBJECTIVES

To review the effects of carbamazepine compared to phenobarbitone monotherapy for people with partial onset seizures or generalized onset tonic-clonic seizures.

SEARCH STRATEGY

The Cochrane Controlled trials register (Cochrane Library Issue 2, 2002); MEDLINE; EMBASE; handsearching; contacting experts and original trial investigators; contacting manufacturers of carbamazepine.

SELECTION CRITERIA

Randomized or quasi-randomized, blinded or unblinded controlled trials in children or adults with partial onset seizures or generalized onset tonic-clonic seizures.

DATA COLLECTION AND ANALYSIS

Outcome measures were (i) time to withdrawal of allocated treatment, (ii) time to 12 month remission, and (iii) time to first seizure. Data were analysed using a stratified logrank analysis with results expressed as hazard ratios (HR) and 95% confidence intervals (CIs), where a HR>1 indicates an event is more likely on phenobarbitone. A test for interaction between treatment and seizure type (partial versus generalized onset) was also undertaken.

MAIN RESULTS

Data are available for 684 participants from four trials, representing 59% of the participants recruited into the nine trials that met our inclusion criteria. The main overall results (HR 95% CI) adjusted for seizure type were, (i) time to withdrawal 1.63(1.23 to 2.15), (ii) time to 12 month remission 0.87(0.65 to 1.17), (iii) time to first seizure 0.85(0.68 to 1.05). The review suggests that time to withdrawal is significantly improved with carbamazepine compared to phenobarbitone. No overall difference between drugs is identified for the outcomes 'time to 12 month remission' and 'time to first seizure'. Statistical heterogeneity was not encountered. An interaction between treatment and seizure type, confirmed statistically, was identified for time to first seizure, where phenobarbitone was favoured for partial onset seizures and carbamazepine for generalized onset tonic-clonic seizures.

REVIEWER'S CONCLUSIONS

We found no overall difference between carbamazepine and phenobarbitone for time to 12 month remission or time to first seizure, however, subgroup analyses for time to first seizure suggest an advantage with phenobarbitone for partial onset seizures and a clinical advantage with carbamazepine for generalized onset tonic-clonic seizures. Phenobarbitone is significantly more likely to be withdrawn, indicating that it is less well tolerated than carbamazepine.

Routine anticonvulsants for treating cerebral malaria

BACKGROUND

Cerebral malaria is a common complication of Plasmodium falciparum infection, and kills over a million people every year. People with cerebral malaria become unconscious, and often have protracted convulsions. It is unclear whether giving anticonvulsant drugs routinely to people with cerebral malaria will improve the outcome of treatment and prevent death.

OBJECTIVES

To evaluate the effect of routine anticonvulsant drugs in people with cerebral malaria.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group specialized trials register (November 2001), The Cochrane Controlled Trials Register (Issue 4, 2001), MEDLINE (1966 to November 2001), EMBASE (1988 to October 2001), LILACS (2001, 40a Edition CD-ROM), Science Citation Index (November 2001), African Index Medicus (1999), reference lists of articles, and research organizations. We also contacted the authors for addtional information.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials of people with cerebral malaria. The trials compared anticonvulsant drugs started on admission to hospital with no anticonvulsant drug or placebo.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data from those trials eligible for inclusion. We assessed the methodological quality of the included trials by considering allocation sequence, concealment of allocation, blinding, and inclusion of all randomized participants. We used Review Manager (version 4.1) for the meta-analysis and also explored possible sources of heterogeneity.

MAIN RESULTS

Three trials with a total of 573 participants met the inclusion criteria. These trials all compared phenobarbitone with placebo or no treatment. In the two trials with adequate allocation concealment, death was more common in the anticonvulsant group (Relative Risk 2.0; 95% confidence interval 1.20 to 3.33; fixed effect model). In all three trials, phenobarbitone compared with placebo or no treatment was associated with fewer convulsions (Relative Risk 0.30; 95% confidence interval 0.19 to 0.45; fixed effect model).

REVIEWER'S CONCLUSIONS

Routine phenobarbitone in cerebral malaria is associated with fewer convulsions but possibly more deaths. Further trials with adequate design, more participants, and different doses of anticonvulsant drugs are needed.

Carbamazepine versus phenytoin monotherapy for epilepsy

BACKGROUND

Worldwide, carbamazepine and phenytoin are commonly used antiepileptic drugs. This review summarizes evidence from randomized controlled trials in which these two drugs have been compared.

OBJECTIVES

To review the best evidence comparing carbamazepine and phenytoin when used as monotherapy in subjects with partial onset seizures, or generalized onset tonic-clonic seizures with or without other generalized seizure types.

SEARCH STRATEGY

We searched: (a) the trial register of the Cochrane Epilepsy Group; (b) The Cochrane Controlled Trials Register (Cochrane Library Issue 4, 2001); (c) MEDLINE 1966-2001. In addition we hand searched relevant journals and contacted the pharmaceutical industry and researchers in the field to seek any ongoing or unpublished studies.

SELECTION CRITERIA

Randomized controlled trials in children or adults with partial onset seizures or generalized onset tonic-clonic seizures. Trials must have included a comparison of carbamazepine monotherapy with phenytoin monotherapy.

DATA COLLECTION AND ANALYSIS

This was an individual patient data review. Outcomes were time to (a) withdrawal of allocated treatment, (b) 12 month remission, (c) six month remission, and (d) first seizure post randomization. Data were analysed using a stratified logrank analysis with results expressed as hazard ratios (HR) and 95% confidence intervals (95% CI), where a HR>1 indicates an event is more likely on phenytoin.

MAIN RESULTS

Individual patient data are available for 551 participants from three trials, representing 63% of the participants recruited into the nine trials that met our inclusion criteria. By convention, for the outcomes time to six and 12 month remission HR>1 indicates a clinical advantage for phenytoin, whilst for time to withdrawal and first seizure HR>1 indicates a clinical advantage for carbamazepine. Results (HR (95% CI)) were: (i) time to withdrawal of allocated treatment 0.97(0.74 to 1.28), (ii) time to 12 month remission 1.00(0.78 to 1.29), (iii) time to six month remission 1.10(0.87 to 1.39), (iv) time to first seizure 0.91(0.74 to 1.12). The results suggest no overall difference between carbamazepine and phenytoin for these outcomes.

REVIEWER'S CONCLUSIONS

We have not found evidence that a significant difference exists between carbamazepine and phenytoin for the outcomes examined in this review. Confidence intervals are wide and the possibility of important differences existing has not been excluded.

Remacemide for drug-resistant localization related epilepsy

BACKGROUND

Epilepsy is a common neurological condition, affecting 0.5 to 1% of the population. Nearly 30 per cent of people with epilepsy have seizures that are refractory to currently available drugs. In response to this problem, potential new drugs are being developed. Remacemide is one of these.

OBJECTIVES

To evaluate the effects of add-on treatment with remacemide upon seizures, adverse effects, cognition and quality of life for people with drug-resistant localization related epilepsy.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group trials register (4 July 2002), the Cochrane Controlled Trials Register (The Cochrane Library Issue 2, 2002) and MEDLINE (28 May 2002). In addition, we contacted AstraZeneca (makers of remacemide) and colleagues in the field to see if they were aware of any trials that we had missed.

SELECTION CRITERIA

Randomized placebo controlled add-on trials of people of any age with localization related seizures, in which an adequate method of concealment of randomization was used. The studies could be blinded or unblinded and be of parallel or crossover design. They had to have a minimum treatment period of eight weeks.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected trials for inclusion and extracted data. Any disagreements were resolved by discussion. Outcomes investigated included 50 per cent or greater reduction in seizure frequency, treatment withdrawal, adverse effects, effects on cognition and quality of life. The primary analyses were by intention-to-treat. Dose response was evaluated in regression models.

MAIN RESULTS

Two parallel group trials were included representing 514 individuals. Daily doses of 300, 600, 800 and 1200mg of remacemide were tested. The overall relative risk (RR) for remacemide versus placebo with 95% confidence intervals(CI) for a 50 per cent or greater reduction in seizure frequency was 1.59(95% CI 0.91 to 2.79). Due to differences in response rates among trials, regression models were unable to provide reliable estimates of responses to individual doses. Regression models did however suggest a significant effect for 800-1200mg remacemide per day. Remacemide was more likely to be withdrawn than placebo, the RR for treatment withdrawal was 1.90(95% CI 1.00 to 3.60). The RR for dizziness indicates that it is significantly associated with remacemide 3.08(99% CI 1.37 to 6.95). Effects on cognition and quality of life were not reported.

REVIEWER'S CONCLUSIONS

Given the modest effect on seizure frequency and significant withdrawal rate it is unlikely that remacemide will be further developed as an antiepileptic drug.

Zonisamide add-on for drug-resistant partial epilepsy

BACKGROUND

The majority of people with epilepsy have a good prognosis and their seizures can be well controlled with the use of a single antiepileptic agent, but up to 30 per cent develop refractory epilepsy, especially those with partial seizures. In this review we summarize the current evidence regarding zonisamide, when used as an add-on treatment for drug-resistant partial epilepsy.

OBJECTIVES

To evaluate the effects of zonisamide when used as an add-on treatment for people with drug -resistant partial epilepsy.

SEARCH STRATEGY

We searched the Cochrane Epilepsy Group trial register (14/12/01), the Cochrane Controlled Trials Register (Cochrane Library Issue 4, 2001). In addition, we contacted Dainippon and Elan Pharma (makers and licensees of zonisamide) and experts in the field to seek any ongoing studies or unpublished studies.

SELECTION CRITERIA

Randomized placebo controlled add-on trials of zonisamide in people with drug-resistant partial epilepsy.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected trials for inclusion and extracted relevant data. Outcomes were: (a) fifty per cent or greater reduction in total seizure frequency; (b) treatment withdrawal (any reason); (c) adverse events. Primary analyses were intention to treat. Summary odds ratios (ORs) were estimated for each outcome.

MAIN RESULTS

Three trials (499 participants) were included. The overall odds ratio (OR, 95% Confidence Interval (CI)) for 50 per cent reduction in seizure frequency compared to placebo was 2.07(1.36 to 3.15) for a 400mg/day dose of zonisamide. When the full treatment period of 12 weeks was considered for all three trials including varied rates of titration to 400mg/day the OR compared to placebo was 2.72(95% CI 1.74 to 4.25). There was insufficient evidence to support a dose response relationship for this outcome. The OR for treatment withdrawal was 1.74(95% CI 1.03 to 2.95). The 99% CI for the following side effects indicate that they are significantly associated with zonisamide: ataxia 3.94(1.23 to 12.57); somnolence 2.11(1.11 to 3.98); agitation 3.52(1.26 to 9.68); agitation and irritability 2.43(1.04 to 5.66) and anorexia 2.98(1.38 to 6.42).

REVIEWER'S CONCLUSIONS

Zonisamide has efficacy as an add-on treatment in people with drug-resistant partial epilepsy. Minimum effective and maximum tolerated doses cannot be identified. The trials reviewed were of 12 week duration and results cannot be used to confirm longer periods of effectiveness in seizure control. The results cannot be extrapolated to monotherapy or to people with other seizure types or epilepsy syndromes.