ILAE treatment guidelines: evidence-based analysis of antiepileptic drug efficacy and effectiveness as initial monotherapy for epileptic seizures and syndromes

Clinical use of antiepileptic drugs at a referral centre for epilepsy

PURPOSE

The National Centre for Epilepsy in Norway admits patients with refractory epilepsy from the whole country. The purpose of this study was to investigate how antiepileptic drugs (AEDs) are used at the centre and compare it with the total consumption in the country and international guidelines regarding clinical use of AEDs.

MATERIAL AND METHODS

A prevalence study was carried out from patient records from 264 patients (136 adults and 128 children). The use of AEDs, gender, polytherapy, common drug combinations, serum concentration measurements, concomitant medication and comorbid conditions were investigated.

RESULTS

Of the 15 AEDs in use, valproate, lamotrigine and levetiracetam were most frequently used. In the country at large, carbamazepine, valproate and lamotrigine were used the most. Valproate and lamotrigine occurred most frequently in combination. In adults, oxcarbazepine and topiramate were used more frequently in women than in men. Children used benzodiazepines three times as often as adults. Newer AEDs were mostly used for partial seizures, in accordance with international guidelines. Thirty-five percent of adults and 20% of children suffered from comorbid CNS-related conditions. The use of concomitant medication was widespread. Serum concentrations were in accordance to recommended therapeutic ranges.

CONCLUSION

The results demonstrate that newer AEDs were much more frequently used at the epilepsy centre than in the country as a whole. The use of polytherapy was common, and therapeutic drug monitoring was used for optimal individualized drug treatment. AEDs were used in accordance to international guidelines and recommendations, which can serve as a reference for other prescribers.

Designing practical evidence-based treatment plans for children with prolonged seizures and status epilepticus

The adverse effects of prolonged seizures and status epilepticus can be reduced through appropriate, prompt, and aggressive intervention. Because most prolonged seizures and status epilepticus episodes begin outside the hospital, it is important to design treatment interventions that can be rendered at home or in school that do not rely entirely on intervention by emergency medical personnel. Factors that make this new approach possible include the use of evidence-based guidelines to inform treatment decisions and the successful development, and government approval, of new formulations of commonly used medications, including rectal diazepam gel and the phenytoin prodrug fosphenytoin. A useful plan should be initiated at the 5-minute to 10-minute mark (not the 30-minute mark) and contain clear, easy-to-read directions that can be implemented by family, school personnel, or emergency medical services who have varying levels of medical sophistication. Four scenarios illustrating these considerations are included and provide examples of plans that fulfill these criteria.

Epilepsy

PURPOSE OF REVIEW

To provide a critical review of studies published between December 2005 and November 2006, and detect the advances of basic and clinical research in epilepsy.

RECENT FINDINGS

The complexity of the mechanisms underlying epileptogenesis and drug resistance was repeatedly highlighted. Seizure diagnosis and classification are still difficult, despite the use of valid and reliable instruments. Even well defined epilepsy syndromes may exhibit complex genetic patterns and atypical electroencephalogram features. Low prevalence rates of active epilepsy have been reported from several countries, suggesting underreporting for sociocultural reasons. Several pregnancy and neonatal factors can be found to increase the risk of epilepsy when accurate data are available from well defined populations. Early remission of seizures does not always predict terminal remission after prolonged follow-up. Cognitive regression may be associated with the presence of interictal electroencephalographic epileptiform abnormalities. A Cochrane review showed lamotrigine to be less frequently withdrawn than carbamazepine. However, these findings are contrasted by clinical practice, which showed no individual drug to be more likely to confer seizure freedom than any other.

SUMMARY

Recent research highlights the complexity of the mechanisms of epileptogenesis and drug response, and the difficulties with the classification of epilepsy into separate phenotypic categories.

Clinical aspects of the ketogenic diet

The ketogenic diet remains a valuable therapeutic option for patients with intractable epilepsy. Clinical aspects of the diet's success may provide insights into epileptogenesis and anticonvulsant action. The diet's efficacy has been established primarily through large case series. The diet has been used successfully in patients with many different epilepsy syndromes in countries around the world. Potential adverse effects can be avoided with careful attention during the diet's initiation and maintenance phases. In the last decade, variations to the classical ketogenic diet have been utilized. Ketogenic diets now are being used for diseases other than epilepsy. This critical analysis of the diet should provide the impetus for further clinical and basic research into the diet's application and mechanisms of action.

Outcomes of newly diagnosed idiopathic generalized epilepsy syndromes in a non-pediatric setting

INTRODUCTION

The prognosis of idiopathic generalized epilepsy syndromes (IGES) in the adult setting may vary from that in children owing to differences in genetic, environmental and lifestyle factors.

METHODS

All patients diagnosed with epilepsy at the Epilepsy Unit, Western Infirmary, Glasgow, between 1981 and 2001 were reviewed.

RESULTS

Of 890 patients, 118 (13%) met the criteria for IGES. Outcomes were known for 103, 66 (64%) of whom achieved remission. The responder rate with sodium valproate was superior (66% vs 45%, P = 0.073) to that with lamotrigine (LTG) particularly in patients with juvenile myoclonic epilepsies (75% vs 39%, P = 0.014). History of febrile seizures was the only factor associated with reduced likelihood of remission (P = 0.032)

CONCLUSIONS

Idiopathic generalized epilepsy syndromes constituted 13% of cases in a largely adult cohort of newly diagnosed epilepsy, most of whom achieved remission usually with a single antiepileptic drug. History of febrile seizures was associated with a poorer outcome.

Prescribing Antiepileptics for the Elderly

The incidence of epilepsy in patients aged >60 years is higher than in any other period of life. Yet, until recently, what was known about the treatment of older patients with epilepsy has been inferred from studies in younger patients. A growing body of clinical evidence focused exclusively on the elderly suggests that, while some issues are similar for older and younger adults, older patients with epilepsy may require even more attention regarding antiepileptic drug (AED) selection than younger patients. This article reviews published guidelines and recommendations to identify explicit recommendations for use of specific AEDs in the elderly, and assesses the extent to which those recommendations have been adopted in clinical practice. We found that while one systematically derived guideline stated that lamotrigine may be a good choice for older patients because of its favourable adverse effect profile, only clinical recommendations based on expert opinion explicitly identified AEDs that are more and less appropriate for use in the elderly. Examination of published studies describing recent AED-prescribing patterns suggests that clinical recommendations have been, at best, slowly adopted. This observation is exemplified by the fact that older patients newly diagnosed with epilepsy are still prescribed phenobarbital--a drug identified as suboptimal in 1985. In order to better understand the delay in adopting clinical recommendations, we examine these findings in light of diffusion of innovations theory, a theory that has been used to understand dissemination of other new medical technologies. According to this theory, while it is too early to suggest that use of second-generation AEDs in the elderly has been delayed, the continued use of phenobarbital in older patients newly diagnosed with epilepsy represents a serious delay in adoption of recent guidelines. Delays may be related to lack of knowledge by primary care clinicians and emergency room physicians (who frequently treat older patients with epilepsy), lack of 'opinion leaders' in primary care and perhaps general neurology, clinicians' focus on seizure control as the primary endpoint in treating patients with epilepsy, and difficulties in changing long-standing prescribing patterns. Research targeting barriers to more appropriate prescribing is needed to determine appropriate strategies for changing AED prescribing practices in the elderly.

Management of Focal-Onset Seizures

Focal-onset seizures are manifestations of abnormal epileptic firing of brain cells in a localised area or areas of the brain. The diagnosis of focal-onset seizures initially entails an EEG, a detailed history from the patient and eyewitnesses, as well as computer tomographic or, preferably, magnetic resonance imaging scans. Video EEG to record ictal events may be necessary to establish the correct diagnosis. Focal seizures are classified according to the International Classification of Epileptic Seizures and International Classification of Epilepsies and Epilepsy Syndromes. It is important to try to decide how the seizure event fits into this system in order to successfully evaluate and optimise treatment, as well as to give detailed information to the patient about their seizures and prognosis. Once the decision to treat the seizures has been made, the physician must choose which medication is the most appropriate to begin with. Carbamazepine, phenytoin or valproic acid (sodium valproate) are often rated as first-line drugs, but factors such as adverse-effect profiles, age, possibility of pregnancy, and concomitant diseases and medication also need to be considered. Most of the newer antiepileptic drugs (AEDs) appear to have good efficacy and better tolerability than the older agents, but evidence to support their superiority is scarce and has led to conflicting advice in several guidelines. Among the newer AEDs, lamotrigine, gabapentin, topiramate and oxcarbazepine have obtained monotherapy indication in many countries. The higher costs of the newer AEDs may inhibit their wider use, especially in poorer countries.