Carlos A. M. Guerreiro

ILAE Treatment Guidelines: Evidence‐based Analysis of Antiepileptic Drug Efficacy and Effectiveness as Initial Monotherapy for Epileptic Seizures and Syndromes

Summary:  Purpose: To assess which antiepileptic medications (AEDs) have the best evidence for long‐term efficacy or effectiveness as initial monotherapy for patients with newly diagnosed or untreated epilepsy.

Updated ILAE evidence review of antiepileptic drug efficacy and effectiveness as initial monotherapy for epileptic seizures and syndromes

The purpose of this report was to update the 2006 International League Against Epilepsy (ILAE) report and identify the level of evidence for long‐term efficacy or effectiveness for antiepileptic drugs (AEDs) as initial monotherapy for patients with newly diagnosed or untreated epilepsy. All applicable articles from July 2005 until March 2012 were identified, evaluated, and combined with the previous analysis (Glauser et al., 2006) to provide a comprehensive update. The prior analysis methodology was utilized with three modifications: (1) the detectable noninferiority boundary approach was dropped and both failed superiority studies and prespecified noninferiority studies were analyzed using a noninferiority approach, (2) the definition of an adequate comparator was clarified and now includes an absolute minimum point estimate for efficacy/effectiveness, and (3) the relationship table between clinical trial ratings, level of evidence, and conclusions no longer includes a recommendation column to reinforce that this review of efficacy/evidence for specific seizure types does not imply treatment recommendations. This evidence review contains one clarification: The commission has determined that class I superiority studies can be designed to detect up to a 20% absolute (rather than relative) difference in the point estimate of efficacy/effectiveness between study treatment and comparator using an intent‐to‐treat analysis. Since July, 2005, three class I randomized controlled trials (RCT) and 11 class III RCTs have been published. The combined analysis (1940–2012) now includes a total of 64 RCTs (7 with class I evidence, 2 with class II evidence) and 11 meta‐analyses. New efficacy/effectiveness findings include the following: levetiracetam and zonisamide have level A evidence in adults with partial onset seizures and both ethosuximide and valproic acid have level A evidence in children with childhood absence epilepsy. There are no major changes in the level of evidence for any other subgroup. Levetiracetam and zonisamide join carbamazepine and phenytoin with level A efficacy/effectiveness evidence as initial monotherapy for adults with partial onset seizures. Although ethosuximide and valproic acid now have level A efficacy/effectiveness evidence as initial monotherapy for children with absence seizures, there continues to be an alarming lack of well designed, properly conducted epilepsy RCTs for patients with generalized seizures/epilepsies and in children in general. These findings reinforce the need for multicenter, multinational efforts to design, conduct, and analyze future clinically relevant adequately designed RCTs. When selecting a patients AED, all relevant variables and not just efficacy and effectiveness should be considered.

A double-blind controlled clinical trial of oxcarbazepine versus phenytoin in adults with previously untreated epilepsy

In the last 5 years oxcarbazepine (OXC) has been registered in many countries for use as first-line and add-on treatment for partial seizures with or without secondarily generalized seizures (PS) and generalized tonic-clonic seizures without partial onset (GTCS). Its use as monotherapy in adults with newly diagnosed epilepsy was investigated in this double-blind, randomized, parallel-group comparison with phenytoin (PHT). A total of 287 adult patients, with either PS or GTCS, were randomized. After retrospective baseline assessment, patients were randomized to OXC or PHT in a 1:1 ratio. The double-blind treatment phase was divided into two periods: a flexible titration period of 8 weeks, followed by 48 weeks of maintenance treatment. In the efficacy analyses, no statistically significant differences were found between the treatment groups. Seventy patients (59.3%) in the OXC group and 69 (58.0%) in the PHT group were seizure-free during the maintenance period. A total of 56 of the patients in the OXC group discontinued treatment prematurely (five because of tolerability reasons) compared to 61 in the PHT group (16 for tolerability reasons). The number of premature discontinuations due to adverse experiences showed a statistically significant difference in favour of OXC. There was no statistically significant difference between the groups with respect to the total number of premature discontinuations. This trial provides further support for the efficacy and safety of OXC as first-line treatment in adults with PS and GTCS. In addition, the results show that OXC has significant advantages over PHT in terms of tolerability.

Seizure outcome and hippocampal atrophy in familial mesial temporal lobe epilepsy

Objective: To describe the clinical, genetic and MR characteristics of patients with familial mesial temporal lobe epilepsy (MTLE). Design/Methods: The familial occurrence of MTLE was identified by a systematic search of family history of seizures in patients followed in the authors’ epilepsy clinic. All probands and, whenever possible, other affected family members underwent EEG and MR investigations. Results: Twenty-two unrelated families with at least two individuals with MTLE were identified by clinical and EEG findings. Ninety-eight individuals with history of seizures were evaluated. Sixty-eight patients fulfilled the diagnostic criteria for MTLE. MRI was performed in 84 patients, and showed hippocampal atrophy with increased T2 signal in 48 (57%). The distribution of hippocampal atrophy according to the seizure outcome groups was 6 of 13 patients (46%) with seizure remission, 16 of 31 (51%) with good seizure control under medication, and all 16 patients with refractory MTLE. Hippocampal atrophy was found also in patients that did not fulfill the criteria for MTLE: 3 of 10 (30%) patients with febrile seizure alone, 6 of 10 (60%) patients with recurrent generalized tonic-clonic seizures, and 1 of 4 (25%) patients with a single partial seizure. Conclusion: Familial MTLE is a clinically heterogeneous syndrome. Hippocampal atrophy was observed in 57% of patients, including those with benign course or seizure remission, indicating that the relationship between hippocampal atrophy and severity of epilepsy might be more complex than previously suspected. In addition, these findings indicate the presence of a strong genetic component determining the development of mesial temporal sclerosis in these families.

Voxel-based morphometry in patients with idiopathic generalized epilepsies.

Idiopathic generalized epilepsies (IGE) are a group of frequent age-related epilepsy syndromes. IGE are clinically characterized by generalized tonic-clonic, myoclonic and absence seizures. According to predominant seizure type and age of onset, IGE are divided in subsyndromes: childhood absence and juvenile absence epilepsy (AE), juvenile myoclonic epilepsy (JME) and generalized tonic-clonic seizures on awakening (GTCS). The limits between these subsyndromes are not well defined, supporting the existence of only one major syndrome. Visual assessment of routine magnetic resonance imaging (MRI) in patients with IGE is normal. MRI voxel-based morphometry (VBM) uses automatically segmented gray and white matter for comparisons, eliminating the investigator bias. We used VBM to study 120 individuals (47 controls, 44 with JME, 24 with AE and 15 with GTCS) to investigate the presence of subtle structural abnormalities in IGE subsyndromes. VBM was performed searching for abnormalities on gray matter concentration (GMC) between patients groups and controls. Compared to controls, JME presented increased GMC in frontobasal region and AE showed increased GMC in the superior mesiofrontal region. The GTCS group did not differ from controls. There were no areas of reduced GMC with the statistical level selected. Region of interest analysis showed increased GMC in the anterior portion of the thalamus in patients with absence seizures. Our results support subtle GMC abnormalities in patients with JME and AE when compared to controls. These findings suggest the existence of different patterns of cortical abnormalities in IGE subsyndromes.

Differences in memory performance and other clinical characteristics in patients with mesial temporal lobe epilepsy with and without hippocampal atrophy

Mesial temporal lobe epilepsy (MTLE) is usually accompanied by memory deficits due to damage to the hippocampal system. In most studies, however, the influence of hippocampal atrophy (HA) is confounded with other variables, such as: type of initial precipitating injury and pathological substrate, effect of lesion (HA) lateralization, history of febrile seizures, status epilepticus, age of seizure onset, duration of epilepsy, seizure frequency, and antiepileptic drugs (AEDs). To investigate the relationship between memory deficits and these variables, we studied 20 patients with MTLE and signs of HA on MRI and 15 MTLE patients with normal high-resolution MRI. The findings indicated that (1) HA, earlier onset of seizures, longer duration of epilepsy, higher seizure frequency, and AEDs (polytherapy) are associated with memory deficits; and (2) there is a close relationship between deficits of verbal memory and left HA, but not between visual memory and right HA.

MRI volumetry shows increased anterior thalamic volumes in patients with absence seizures

The interaction between thalamus and cortex appears to be critical to the pathophysiology of idiopathic generalized epilepsies (IGEs). The objective of this study was to investigate thalamic volumes of a group of patients with IGEs using high-resolution MRI. Thalamic segmentation was performed by the same rater, who was unaware of the diagnosis. Thalamic volumes were divided into anterior half and posterior half. One hundred forty-seven patients were scanned (71 with juvenile myoclonic epilepsy, 49 with generalized tonic-clonic seizures only, and 27 with absence epilepsy). Subgroup analyses with corrections for multiple comparisons showed that, when compared with those of controls, anterior thalamic volumes were increased in patients with absence epilepsy and juvenile myoclonic epilepsy with absence seizures, but not in patients with generalized tonic-clonic seizures only and juvenile myoclonic epilepsy without absence seizures. Our results demonstrated that the anterior thalamus is structurally different in patients with IGEs and absence seizures as compared with patients with IGEs without absence seizures.

Brain Single Photon Emission Computed Tomography Imaging in Landau-Kleffner Syndrome

Summary: Five right–handed children with Landau‐Kleffner syndrome (LKS) who had disease onset between the ages of 3 and 9 years were studied with EEG and single‐photon emission computed tomography (SPECT) before and, in four cases, after 6 months of corticosteroid treatment. EEG findings included both focal and generalized spikes as well as spike‐wave discharges with bilateral temporal predominance. These increased markedly during sleep in 1 child, and continuous spike‐and‐wave complexes appeared during slow‐wave sleep in another patient. Neuropsychological testing demonstrated verbal auditory agnosia. Magnetic resonance imaging (MRI) was performed in 4 children and was normal. Brain SPECT imaging demonstrated abnormal perfusion in the left temporal lobe in all patients. The response to corticosteroid therapy was mixed. Our findings reinforce the concept that LKS is a functional disease affecting the language‐dominant brain areas. We conclude that SPECT imaging may be of diagnostic assistance in the evaluation of this syndrome of unknown etiology.

Headache during gestation: evaluation of 1101 women.

OBJECTIVE The purpose of this study was to evaluate the presence of headache in women with a previous history or new-onset headache during the current gestation, classify the findings, and describe the clinical characteristics and outcome of the headache. METHODS From January/1998 to June/2002 we prospectively evaluated 1101 pregnant women (12-45 years old), with a history of headache, at two prenatal clinics and an inpatient obstetric public hospital. Women were interviewed using a semi-structured questionnaire during the first, second, and third gestation trimesters and immediately after delivery. All interviews were conducted by one of the authors, using the International Headache Society Classification (IHSC-2004). RESULTS In 1029 women there was a history of headache prior to the current pregnancy, 36 (3.4%) women first experienced headache during this pregnancy and 40 patients experienced new types of headache. In these 76 patients with new onset headache during pregnancy, 40 had secondary headache (52.6%), 31 had primary headache (40.8%), and 5 had headache not classified elsewhere (6.6%). According to IHSC- 2004 criteria, we found migraine in 848/1029 women (82.4%), with pregestational headache. CONCLUSIONS Most of the pregnant women presented with headache, mainly in migraine, prior to pregnancy, and most of the headaches improved or disappeared during the second and third gestation trimester. In a relatively small number of pregnant women, a new type of headache started during the gestation.

MRI reveals structural abnormalities in patients with idiopathic generalized epilepsy

Objective: To evaluate MRI findings in a large group of patients with idiopathic generalized epilepsies. Methods: Idiopathic generalized epilepsies were diagnosed according to clinical and EEG criteria following International League Against Epilepsy recommendations. MRI was performed in a 2.0 T scanner using a previously established epilepsy protocol. Images were reviewed, and any abnormality was reported. Patients were divided in those with and without MRI abnormalities. Comparisons were made between these groups concerning age, age at seizure onset, subsyndrome, EEG findings, and seizure control. Results: Of the 134 MRIs evaluated, 33 (24%) showed abnormalities, most of which (88%) were nonspecific. There were eight main abnormalities: arachnoid cyst, diffuse cortical atrophy, basal ganglia abnormalities (signal alterations and prominent perivascular spaces), ventricular abnormalities (uni- or bilateral increased volume of the lateral ventricles), white matter abnormalities (increased T2 signal in the frontal lobes), reduced hippocampal volume, focal gyral abnormality, and area of gliosis in the frontal lobe. Comparisons between the groups showed a higher proportion of EEG focalities in patients with abnormal MRI, which were in most part concordant with the location of the MRI abnormalities. Conclusions: Twenty-four percent of patients with idiopathic generalized epilepsies had MRI abnormalities. However, the majority of these abnormalities were nonspecific.