Revising and refining the epilepsy classification system: priorities from a developing world perspective

No association of GABRA1 rs2279020 and GABRA6 rs3219151 polymorphisms with risk of epilepsy and antiepileptic drug responsiveness in Asian and Arabic populations: Evidence from a meta-analysis with trial sequential analysis

The γ-aminobutyric acid type A receptors (GABAAR) have been reported to contribute to the pathogenesis of epilepsy and the recurrence of chronic seizures. Genetic polymorphisms in GABRA1 and GABRA6 may confer a high risk of epilepsy and multiple drug resistance, but with conflicting results. We aimed to assess the association of GABRA1 rs2279020 and GABRA6 rs3219151 with epilepsy risk using a meta-analysis. The databases of Pubmed, Ovid, Web of Science, and China National Knowledge Infrastructure were searched. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were computed to evaluate the association between the polymorphisms and epilepsy risk using a fixed- or random-effect model. Trial sequential analysis (TSA) was performed to assess the results of the meta-analysis. No significant association between the GABRA1 rs2279020 and GABRA6 rs3219151 and the risk of epilepsy was found in the Asian and Arabic populations. The negative results were also observed when comparing the GABRA1 rs2279020 and GABRA6 rs3219151 polymorphism to antiepileptic drug responsiveness. The trial sequential analysis confirmed the results of the meta-analysis. This meta-analysis suggests that GABRA1 rs2279020 and GABRA6 rs3219151 are not risk factors for the etiology of epilepsy and antiepileptic drug responsiveness in the Asian and Arabic populations.

Classifying epilepsy pragmatically: Past, present, and future

The classification of epilepsy is essential for people with epilepsy and their families, healthcare providers, physicians and researchers. The International League Against Epilepsy proposed updated seizure and epilepsy classifications in 2017, while another four-dimensional epilepsy classification was updated in 2019. An Integrated Epilepsy Classification system was proposed in 2020. Existing classifications, however, lack consideration of important pragmatic factors relevant to the day-to-day life of people with epilepsy and stakeholders. Despite promising developments, consideration of comorbidities in brain development, genetic causes, and environmental triggers of epilepsy remains largely user-dependent in existing classifications. Demographics of epilepsy have changed over time, while existing classification schemes exhibit caveats. A pragmatic classification scheme should incorporate these factors to provide a nuanced classification. Validation across disparate contexts will ensure widespread applicability and ease of use. A team-based approach may simplify communication between healthcare personnel, while an individual-centred perspective may empower people with epilepsy. Together, incorporating these elements into a modern but pragmatic classification scheme may ensure optimal care for people with epilepsy by emphasising cohesiveness among its myriad users. Technological advancements such as 7T MRI, next-generation sequencing, and artificial intelligence may affect future classification efforts.

A systematic review and meta-analysis of the association of ABCC2/ABCG2 polymorphisms with antiepileptic drug responses in epileptic patients

PURPOSE

Accumulating evidence indicates that genetic polymorphisms in ATP-binding cassette superfamily members, such asABCC2 and ABCG2, alter responses to antiepileptic drugs (AEDs); however, this evidence is controversial and inconclusive. To provide strong evidence of the association between common polymorphisms in ABCC2 and ABCG2 and AED responses in patients with epilepsy, we performed a systematic review and meta-analysis.

METHODS

A literature search of electronic databases (PubMed, EBSCO, Ovid and the China National Knowledge Infrastructure) was performed. To evaluate the association of genetic polymorphisms inABCC2 and ABCG2 and risk of AED treatment, we calculated pooled odds ratios (ORs) and 95 % confidence intervals (CIs) using a fixed- or random-effect model.

RESULTS

A significant association of theABCC2 rs717620 polymorphism with resistance to AEDs was found in the overall pooled populations (homozygous comparison: OR = 1.77, 95 % CI, 1.27-2.48; dominant model: OR = 1.23, 95 % CI, 1.06-1.43; recessive model: OR = 1.75, 95 % CI, 1.28-2.40) and Asians (dominant model: OR = 1.21, 95 % CI, 1.03-1.42; recessive model: OR = 1.80, 95 % CI, 1.30-2.50). Using a recessive model, a similarly significant association of ABCC2 rs3740066 with AED resistance was observed in the overall pooled populations (OR = 2.29, 95 % CI, 1.44-3.64) and Asians (OR = 2.53, 95 % CI, 1.56-4.08). However, ABCC2 rs2273697, ABCG2 rs2231137 and rs2231142 were not found to be associated with AED responsiveness.

CONCLUSION

This meta-analysis suggests thatABCC2 rs717620 and rs3740066 are risk factors that predict responses to AEDs in epileptic patients.

Molecular targets in cerebral malaria for developing novel therapeutic strategies

Cerebral malaria (CM) is the severe neurological complication associated with Plasmodium falciparum infection. In clinical settings CM is predominantly characterized by fever, epileptic seizures, and asexual forms of parasite on blood smears, coma and even death. Cognitive impairment in the children and adults even after survival is one of the striking consequences of CM. Poor diagnosis often leads to inappropriate malaria therapy which in turn progress into a severe form of disease. Activation of multiple cell death pathways such as Inflammation, oxidative stress, apoptosis and disruption of blood brain barrier (BBB) plays critical role in the pathogenesis of CM and secondary brain damage. Thus, understanding such mechanisms of neuronal cell death might help to identify potential molecular targets for CM. Mitigation strategies for mortality rate and long-term cognitive deficits caused by existing anti-malarial drugs still remains a valid research question to ask. In this review, we discuss in detail about critical neuronal cell death mechanisms and the overall significance of adjunctive therapy with recent trends, which provides better insight towards establishing newer therapeutic strategies for CM.

Adverse effects & drug load of antiepileptic drugs in patients with epilepsy: Monotherapy versus polytherapy

Background & objectives:

Although the need for a combination of antiepileptic drugs (AEDs) in the treatment of epilepsy is well justified, but an associated increase in adverse effects (AEs) lends a restriction to polytherapy. The aim of this study was to evaluate AEs and drug load (prescribed daily dose/defined daily doses) of AEDs in patients with epilepsy (PWE).

Methods:

Consecutive PWEs attending Epilepsy clinic in a tertiary care hospital in New Delhi, India, were enrolled in the study. Demographic variables, such as age, gender, diagnosis, age at onset of seizures, frequency of seizures, use of all AEDs and adverse event profile (AEP) score were noted. Routine laboratory tests including lipid profile, fasting blood glucose, haematological parameters and liver and kidney function tests were done.

Results:

A total of 697 consecutive patients were included in this study. Of them, 64.4 per cent were male; mean age was 29.6 ± 10.6 yr. Generalized seizures and focal seizures were recorded in n=386 (55.4%) and n=311 (44.6%), respectively. Monotherapy and polytherapy with two and greater than or equal to three AEDs were prescribed in 264 (37.9%), 243 (34.9%) and 190 (27.2%) patients, respectively. The average AED load, duration of treatment as well as AEP score were found to be significantly higher in combination of greater than or equal to three AEDs as compared to both monotherapy and combination of two AEDs, whereas no significant difference was observed between monotherapy and combination of two AEDs. Patients on monotherapy were in good control of seizures as compared to polytherapy. There was no significant change in biochemical parameters between the groups.

Interpretation & conclusions:

Polytherapy with combination of greater than or equal to three AEDs was associated with higher AEs and lower seizure control as compared to both monotherapy and combination of two AEDs. AEs did not correlate with AED load, seizure type, gender and age of the patients but were associated with both numbers of AEDs as well as seizure frequency in PWE.

Cognition, behavior, and the ILAE Classification of the Epilepsies: A view from Africa

Recent ILAE revisions to the definition and classification of the epilepsies have highlighted cognitive-behavioral comorbidities (CBCs). Integrating a CBC dimension within a formal classification scheme would more fully account for the burden of epilepsy. This would be technically challenging, because we use fundamentally different methods to conceptualize, define, and diagnose CBCs that require additional expertise. In low resource settings such as sub-Saharan Africa (SSA), CBC burden is high. Existing classification systems are inevitably simplified in practice, because complex classifications require training and technologies that rarely exist in these settings. This makes low-resource settings a good place to develop simple methods to integrate CBCs into existing classifications so that they ultimately will communicate the full burden of epilepsy. This article is part of a Special Issue entitled "The new approach to classification: Rethinking cognition and behavior in epilepsy".

Text Classification towards Detecting Misdiagnosis of an Epilepsy Syndrome in a Pediatric Population

When attempting to identify a specific epilepsy syndrome, physicians are often unable to make or agree upon a diagnosis. This is further complicated by the fact that the current classification and diagnosis of epilepsy requires specialized training and the use of resources not typically available to the average clinician, such as training to recognize specific seizure types and electroencephalography (EEG). Even when training and resources are available, expert epileptologists often find it challenging to identify seizure types and to distinguish between specific epilepsy syndromes. Information relevant to the diagnosis is present in narrative form in the medical record across several visits for an individual patient. Our ultimate goal is to create a system that will assist physicians in the diagnosis of epilepsy. This paper explores, as a baseline, text classification methods that attempt to correlate the narrative text features to the diagnosis of West syndrome (Infantile Spasms), using data from Phoenix Children's Hospital (PCH). We tested these methods against a dataset containing known (coded) diagnosis of West Syndrome, and found the best performing method to have a precision / recall / f-measure of 76.8 / 66.7 / 71.4 when evaluated with 10-fold cross validation.

State of the Art Approach to the Classification of Epileptic Seizures and Epilepsies

In the light of the latest knowledge acquired from clinical and laboratory research dealing with genetic, molecular biology and neuroimaging, existing classifications were successively revised by the International League Against Epilepsy (ILAE) in 2001, 2006, and 2010. In the latest classification established in 2010, proposals articulated radical changes in terms of concepts and definitions of the previously published classifications and put forward new classifications for epileptic seizures, epilepsies and electroclinical syndromes. This review refers to the changes of the new classification with their reasons and criticisms.

Proposed International League Against Epilepsy Classification 2010: new insights

The International League Against Epilepsy (ILAE) Classification of Seizures in 1981 and the Classification of the Epilepsies, in 1989 have been widely accepted the world over for the last 3 decades. Since then, there has been an explosive growth in imaging, genetics and other fields in the epilepsies which have changed many of our concepts. It was felt that a revision was in order and hence the ILAE commissioned a group of experts who submitted the initial draft of this revised classification in 2010. This review focuses on what are the strengths and weaknesses of this new proposed classification, especially in the context of a developing country.

Syncope in patients with drug-resistant epilepsy without apparent cardiovascular disease

Epilepsy and syncope are clinical conditions with high prevalence rates in the general population, and the differential diagnosis between them is difficult. Objective To assess the frequency of syncope in patients diagnosed with drug-resistant epilepsy (DRE) without appa-rent heart disease, to investigate the relationship between clinical and electroencephalographic (EEG) changes, and to verify the role of the inclination test (IT). Method An open, prospective study from 2004 to 2006, including 35 consecutive patients from the Epilepsy Program of Hospital Universitário Clementino Fraga Filho who were diagnosed with DRE without apparent heart disease. Results The frequency of syncope was 25.7% (n=9), with a significant prevalence in women. Vasovagal syncope (VVS) was the most frequent diagnosis. Conclusion We found a significant association between syncope and the presence of autonomic symptoms (p=0.005). The IT plays an important role in the differential diagnosis of patients with DRE presenting with autonomic symptoms, regardless of EEG results and brain magnetic resonance imaging (MRI) abnormalities.

Epilepsy care guidelines for low- and middle- income countries: From WHO mental health GAP to national programs

In 2011, the World Health Organization's (WHO) mental health Gap Action Programme (mhGAP) released evidence-based epilepsy-care guidelines for use in low and middle income countries (LAMICs). From a geographical, sociocultural, and political perspective, LAMICs represent a heterogenous group with significant differences in the epidemiology, etiology, and perceptions of epilepsy. Successful implementation of the guidelines requires local adaptation for use within individual countries. For effective implementation and sustainability, the sense of ownership and empowerment must be transferred from the global health authorities to the local people. Sociocultural and financial barriers that impede the implementation of the guidelines should be identified and ameliorated. Impact assessment and program revisions should be planned and a budget allocated to them. If effectively implemented, as intended, at the primary-care level, the mhGAP guidelines have the potential to facilitate a substantial reduction in the epilepsy treatment gap and improve the quality of epilepsy care in resource-limited settings.

Neurocysticercosis in sub-Saharan Africa: a review of prevalence, clinical characteristics, diagnosis, and management

Neurocysticercosis has been recognized as a major cause of secondary epilepsy worldwide. So far, most of the knowledge about the disease comes from Latin America and the Indian subcontinent. Unfortunately, in sub-Saharan Africa the condition was neglected for a long time, mainly owing to the lack of appropriate diagnostic tools. This review therefore focuses on the prevalence of neurocysticercosis in sub-Saharan Africa, the clinical picture with emphasis on epilepsy, as well as the diagnosis and treatment of neurocysticercosis and its related epilepsy/epileptic seizures in African resource-poor settings.