Levetiracetam, lamotrigine, and phenobarbital in patients with epileptic seizures and Alzheimer's disease

Presynaptic proteins complexin-I and complexin-II differentially influence cognitive function in early and late stages of Alzheimer's disease

Progressive accumulation of Alzheimer's disease-related pathology is associated with cognitive dysfunction. Differences in cognitive reserve may contribute to individual differences in cognitive function in the presence of comparable neuropathology. The protective effects of cognitive reserve could contribute differentially in early versus late stages of the disease. We investigated presynaptic proteins as measures of brain reserve (a subset of total cognitive reserve), and used Braak staging to estimate the progression of Alzheimer's disease. Antemortem evaluations of cognitive function, postmortem assessments of pathologic indices, and presynaptic protein analyses, including the complexins I and II as respective measures of inhibitory and excitatory terminal function, were assayed in multiple key brain regions in 418 deceased participants from a community study. After covarying for demographic variables, pathologic indices, and overall synapse density, lower brain complexin-I and -II levels contributed to cognitive dysfunction (P < 0.01). Each complexin appeared to be dysregulated at a different Braak stage. Inhibitory complexin-I explained 14.4% of the variance in global cognition in Braak 0-II, while excitatory complexin-II explained 7.3% of the variance in Braak V-VI. Unlike other presynaptic proteins, complexins did not colocalize with pathologic tau within neuritic plaques, suggesting that these functional components of the synaptic machinery are cleared early from dystrophic neurites. Moreover, complexin levels showed distinct patterns of change related to memory challenges in a rat model, supporting the functional specificity of these proteins. The present results suggest that disruption of inhibitory synaptic terminals may trigger early cognitive impairment, while excitatory terminal disruption may contribute relatively more to later cognitive impairment.

Huperzine A: A promising anticonvulsant, disease modifying, and memory enhancing treatment option in Alzheimer's disease

Alzheimer's disease (AD) is the most frequent cause of dementia. Besides cognitive deterioration, patients with AD are prone to seizures - more than 20% of patients diagnosed with AD experience at least one unprovoked seizure and up to 7% have recurrent seizures. Although available antiepileptic drugs (AEDs) may suppress seizures in patients with AD, they may also worsen cognitive dysfunction and increase the risk of falls. On the basis of preclinical studies, we hypothesize that Huperzine A (HupA), a safe and potent acetylcholinesterase (AChE) inhibitor with potentially disease-modifying qualities in AD, may have a realistic role as an anticonvulsant in AD.

Treatment of epilepsy for people with Alzheimer's disease

BACKGROUND

Any type of seizure can be observed in Alzheimer's disease (AD). Antiepileptic drugs seem to prevent the recurrence of epileptic seizures in most people with AD. There are pharmacological and non-pharmacological treatments for epilepsy in people with AD. There are no current systematic reviews to evaluate the efficacy and tolerability of the treatment. This review aims to review those different modalities.

OBJECTIVES

To assess the efficacy and tolerability of the treatment of epilepsy for people with Alzheimer's disease (AD) (including sporadic AD and dominantly inherited AD).

SEARCH METHODS

We searched the Cochrane Epilepsy Group Specialized Register (1 February 2016), the Cochrane Central Register of Controlled Trials (1 February 2016), MEDLINE (Ovid, 1 February 2016) and ClinicalTrials.gov (1 February 2016). In an effort to identify further published, unpublished and ongoing trials, we searched ongoing trials' registers, reference lists and relevant conference proceedings, and contacted authors and pharmaceutical companies.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials investigating treatment for epilepsy in people with AD, with the outcomes of proportion of seizure freedom or experiencing adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the titles and abstracts of identified records, selected studies for inclusion, extracted data, cross-checked the data for accuracy and assessed the methodological quality. We performed no meta-analyses due to the limited available data.

MAIN RESULTS

We included one randomised controlled trial with 95 participants. Concerning the proportion of participants with seizure freedom, no significant differences were found in levetiracetam (LEV) versus lamotrigine (LTG) (risk ratio (RR) 1.20, 95% confidence interval (CI) 0.53 to 2.71), in levetiracetam versus phenobarbital (PB) (RR 1.01, 95% CI 0.47 to 2.19), or in LTG versus PB (RR 0.84, 95% CI 0.35 to 2.02). It seemed that LEV could improve cognition and LTG could relieve depression; while PB and LTG could worsen cognition, and LEV and PB could worsen mood. We judged the quality of the evidence to be very low.

AUTHORS' CONCLUSIONS

This review does not provide sufficient evidence to support LEV, PB and LTG for the treatment of epilepsy in people with AD. Regarding the efficacy and tolerability, no significant differences were found between LEV, PB and LTG. In the future, large randomised, double-blind, controlled, parallel-group clinical trials are required to determine the efficacy and tolerability of treatment for epilepsy in people with AD.

Synaptic Vesicle Glycoprotein 2A Ligands in the Treatment of Epilepsy and Beyond

The synaptic vesicle glycoprotein SV2A belongs to the major facilitator superfamily (MFS) of transporters and is an integral constituent of synaptic vesicle membranes. SV2A has been demonstrated to be involved in vesicle trafficking and exocytosis, processes crucial for neurotransmission. The anti-seizure drug levetiracetam was the first ligand to target SV2A and displays a broad spectrum of anti-seizure activity in various preclinical models. Several lines of preclinical and clinical evidence, including genetics and protein expression changes, support an important role of SV2A in epilepsy pathophysiology. While the functional consequences of SV2A ligand binding are not fully elucidated, studies suggest that subsequent SV2A conformational changes may contribute to seizure protection. Conversely, the recently discovered negative SV2A modulators, such as UCB0255, counteract the anti-seizure effect of levetiracetam and display procognitive properties in preclinical models. More broadly, dysfunction of SV2A may also be involved in Alzheimer's disease and other types of cognitive impairment, suggesting potential novel therapies for levetiracetam and its congeners. Furthermore, emerging data indicate that there may be important roles for two other SV2 isoforms (SV2B and SV2C) in the pathogenesis of epilepsy, as well as other neurodegenerative diseases. Utilization of recently developed SV2A positron emission tomography ligands will strengthen and reinforce the pharmacological evidence that SV2A is a druggable target, and will provide a better understanding of its role in epilepsy and other neurological diseases, aiding in further defining the full therapeutic potential of SV2A modulation.

A Mitochondrial Role of SV2a Protein in Aging and Alzheimer's Disease: Studies with Levetiracetam

Aberrant neuronal network activity associated with neuronal hyperexcitability seems to be an important cause of cognitive decline in aging and Alzheimer's disease (AD). Out of many antiepileptics, only levetiracetam improved cognitive dysfunction in AD patients and AD animal models by reducing hyperexcitability. As impaired inhibitory interneuronal function, rather than overactive neurons, seems to be the underlying cause, improving impaired neuronal function rather than quieting overactive neurons might be relevant in explaining the lack of activity of the other antiepileptics. Interestingly, improvement of cognitive deficits by levetiracetam caused by small levels of soluble Aβ was accompanied by improvement of synaptic function and plasticity. As the negative effects of Aβ on synaptic plasticity strongly correlate with mitochondrial dysfunction, wehypothesized that the effect of levetiracetam on synaptic activity might be raised by an improved mitochondrial function. Accordingly, we investigated possible effects of levetiracetam on neuronal deficits associated with mitochondrial dysfunction linked to aging and AD. Levetiracetam improved several aspects of mitochondrial dysfunction including alterations of fission and fusion balance in a cell model for aging and early late-onset AD. We demonstrate for the first time, using immunohistochemistry and proteomics, that the synaptic vesicle protein 2A (SV2a), the molecular target of levetiracetam, is expressed in mitochondria. In addition, levetiracetam shows significant effect on the opening of the mitochondrial permeability transition pore. Importantly, the effects of levetiracetam were significantly abolished when SV2a was knockdown using siRNA. In conclusion, interfering with the SV2a protein at the mitochondrial level and thereby improving mitochondrial function might represent an additional therapeutic effect of levetiracetam to improve symptoms of late-onset AD.

Chronic treatment with levetiracetam reverses deficits in hippocampal LTP in vivo in experimental temporal lobe epilepsy rats

Temporal lobe epilepsy (TLE), the common form of epilepsy in adults, often displays complex partial seizures and cognitive deficits. The underlying mechanisms of such deficits are not yet well understood. Many contributing factors, such as initial epileptogenic lesion, seizure type, age of onset, and treatment side effects have been proposed. Levetiracetam (LEV) is a novel anti-epileptic drug (AED) used to treat partial seizures and idiopathic generalized epilepsy. It has been suggested that LEV exerts antiepileptic properties by modulation of synaptic release of neurotransmitters. However, its neuroprotective effects on learning and memory are not yet well demonstrated. Here we showed the impairment of spatial memory in the pilocarpine-induced experimental TLE rats, which can be improved by LEV. Furthermore, we found chronic LEV treatment partially reversed the SE-induced synaptic dysfunction in hippocampal LTP induction in vivo. In addition, LEV treatment can alleviate the SE-induced abnormal GluR1 phosphorylation at Ser(831) site, which may contribute to the rescue of synaptic transmission. These results indicate the neuroprotective role for LEV while it exhibits an antiseizure effect on experimental epileptic models.

Cognitive deterioration in adult epilepsy: Does accelerated cognitive ageing exist?

A long-standing concern has been whether epilepsy contributes to cognitive decline or so-called 'epileptic dementia'. Although global cognitive decline is generally reported in the context of chronic refractory epilepsy, it is largely unknown what percentage of patients is at risk for decline. This review is focused on the identification of risk factors and characterization of aberrant cognitive trajectories in epilepsy. Evidence is found that the cognitive trajectory of patients with epilepsy over time differs from processes of cognitive ageing in healthy people, especially in adulthood-onset epilepsy. Cognitive deterioration in these patients seems to develop in a 'second hit model' and occurs when epilepsy hits on a brain that is already vulnerable or vice versa when comorbid problems develop in a person with epilepsy. Processes of ageing may be accelerated due to loss of brain plasticity and cognitive reserve capacity for which we coin the term 'accelerated cognitive ageing'. We believe that the concept of accelerated cognitive ageing can be helpful in providing a framework understanding global cognitive deterioration in epilepsy.

Medical management of epileptic seizures: challenges and solutions

Epilepsy is one of the most common neurologic illnesses. This condition afflicts 2.9 million adults and children in the US, leading to an economic impact amounting to $15.5 billion. Despite the significant burden epilepsy places on the population, it is not very well understood. As this understanding continues to evolve, it is important for clinicians to stay up to date with the latest advances to provide the best care for patients. In the last 20 years, the US Food and Drug Administration has approved 15 new antiepileptic drugs (AEDs), with many more currently in development. Other advances have been achieved in terms of diagnostic modalities like electroencephalography technology, treatment devices like vagal nerve and deep-brain stimulators, novel alternate routes of drug administration, and improvement in surgical techniques. Specific patient populations, such as the pregnant, elderly, those with HIV/AIDS, and those with psychiatric illness, present their own unique challenges, with AED side effects, drug interactions, and medical-psychiatric comorbidities adding to the conundrum. The purpose of this article is to review the latest literature guiding the management of acute epileptic seizures, focusing on the current challenges across different practice settings, and it discusses studies in various patient populations, including the pregnant, geriatric, those with HIV/AIDS, comatose, psychiatric, and "pseudoseizure" patients, and offers possible evidence-based solutions or the expert opinion of the authors. Also included is information on newer AEDs, routes of administration, and significant AED-related drug-interaction tables. This review has tried to address only some of these issues that any practitioner who deals with the acute management of seizures may encounter. The document also highlights the numerous avenues for new research that would help practitioners optimize epilepsy management.

Antiepileptic drugs as a new therapeutic concept for the prevention of cognitive impairment and Alzheimer’s disease. Recent advances

Introduction.Excessive accumulation of amyloid-beta (Aβ) peptides in the brain results initially in mild cognitive impairment (MCI) and finally in Alzheimer’s disease (AD). Evidences from experimental and clinical studies show that pathological hyperexcitability of hippocampal neurons is a very early functional impairment observed in progressive memory dysfunctions. Therefore, antiepileptic drugs (AEDs) whose mechanism of action is aimed at inhibition of such neuronal hyperexcitability, seems to be an rationale choice for MCI and AD treatment.

Aim.To provide data from experimental and clinical studies on: 1. The unfavorable impact of neuronal hyperexcitability, mainly within the hippocampus, on cognitive processes. 2. Efficacy of AEDs against such abnormally elevated neuronal activity for the prevention of progressive cognitive impairment.

Methods.A literature review of publications published within the last fifteen years, was conducted using the PubMed database.

Review.The authors describe Aβ-induced hyperexcitability of hippocampal nerve cells as the cause of cognitive deficits, the connection of such activity with an increased risk of seizures and epilepsy in patients with MCI/AD, and finally the efficacy of AEDs: valproic acid (VPA), phenytoin (PHT), topiramate (TPM), lamotrigine (LTG), ethosuximide (ESM) and levetiracetam (LEV) in the prevention of cognitive impairment in experimental models and patients with MCI/AD.

Conclusions.The majority of the studied AEDs improve cognitive dysfunction in various experimental models of Aβ-induced brain pathology with accompanied neuronal hyperexcitability. The promising results achieved for LEV in animal models of cognitive impairment were also confirmed in patients with MCI/AD. LEV was well-tolerated and it’s beneficial antidementive effect was confirmed by memory tests and fMRI examination. In conclusion, the use of AEDs could be a novel therapeutic concept for preventing cognitive impairment in patients with Aβ-associated brain pathology.

Dissecting Alzheimer disease in Down syndrome using mouse models

Down syndrome (DS) is a common genetic condition caused by the presence of three copies of chromosome 21 (trisomy 21). This greatly increases the risk of Alzheimer disease (AD), but although virtually all people with DS have AD neuropathology by 40 years of age, not all develop dementia. To dissect the genetic contribution of trisomy 21 to DS phenotypes including those relevant to AD, a range of DS mouse models has been generated which are trisomic for chromosome segments syntenic to human chromosome 21. Here, we consider key characteristics of human AD in DS (AD-DS), and our current state of knowledge on related phenotypes in AD and DS mouse models. We go on to review important features needed in future models of AD-DS, to understand this type of dementia and so highlight pathogenic mechanisms relevant to all populations at risk of AD.

The influence of levetiracetam in cognitive performance in healthy individuals: neuropsychological, behavioral and electrophysiological approach

OBJECTIVE

The present study sought to analyze the influence of Levetiracetam (LEV) in cognitive performance by identifying the changes produced by LEV in reaction time, in neuropsychological assessment of attention and memory and in absolute theta power in frontal activity.

METHODS

Twelve healthy subjects (5 men and 7 women; mean age, 30.08 years, standard deviation, 4.71) were recruited for this study. The neuropsychological tests: Trail Making Test (A and B), Digit Span (direct and indirect numerical orders/working memory); Stroop test (inhibitory control of attention); Tower of London (planning and decision-making) and a quantitative electroencephalography were applied in 2 different days after and before the participants ingested the capsule of placebo or 500 mg LEV.

RESULTS

A two-way-ANOVA was implemented to observe the interaction between conditions (placebo or LEV 500 mg) and moments (pre- and post-ingestion of LEV or placebo). The data were analyzed by the SPSS statistical package (p<0.05). For the neuropsychological parameter, the Trail Making Test (A) was the only test that showed significant difference for condition in the task execution time (p=0.026). Regarding the reaction time in the behavioral parameter, an interaction between both factors (p=0.034) was identified through a two-way-ANOVA (condition versus moment). Electrophysiological measures showed a significant interaction for electrodes: F7, F3, and FZ.

CONCLUSIONS

The findings showed that LEV promotes an important cognitive enhancement in the executive functions.

Seizures in Alzheimer's disease

Alzheimer's disease (AD) increases the risk for late-onset seizures and neuronal network abnormalities. An elevated co-occurrence of AD and seizures has been established in the more prevalent sporadic form of AD. Recent evidence suggests that nonconvulsive network abnormalities, including seizures and other electroencephalographic abnormalities, may be more commonly found in patients than previously thought. Patients with familial AD are at an even greater risk for seizures, which have been found in patients with mutations in PSEN1, PSEN2, or APP, as well as with APP duplication. This review also provides an overview of seizure and electroencephalography studies in AD mouse models. The amyloid-β (Aβ) peptide has been identified as a possible link between AD and seizures, and while Aβ is known to affect neuronal activity, the full-length amyloid precursor protein (APP) and other APP cleavage products may be important for the development and maintenance of cortical network hyperexcitability. Nonconvulsive epileptiform activity, such as seizures or network abnormalities that are shorter in duration but may occur with higher frequency, may contribute to cognitive impairments characteristic of AD, such as amnestic wandering. Finally, the review discusses recent studies using antiepileptic drugs to rescue cognitive deficits in AD mouse models and human patients. Understanding the mechanistic link between epileptiform activity and AD is a research area of growing interest. Further understanding of the connection between neuronal hyperexcitability and Alzheimer's as well as the potential role of epileptiform activity in the progression of AD will be beneficial for improving treatment strategies.

Epilepsy in patients with Alzheimer's disease: A systematic review

Alzheimer's disease (AD) and epilepsy are common disorders in the elderly. Evidence demonstrates that patients with AD have an increased risk of developing epilepsy and seizures.

Objective

To review epidemiological, clinical and treatment aspects of epilepsy and AD.

Methods

We reviewed databases (PubMED, LiLACS, Scielo) conducting a search for manuscripts using the terms Alzheimer's disease and epilepsy.

Results

Manuscripts related to the areas of interest were reviewed. Studies revealed that epilepsy is more frequent among AD patients. The combined presence of the two disorders may be related to mechanisms of neuronal hyperexcitability as a consequence of amyloid-beta protein (Aβ) or phosphorylated tau accumulation, as well as to structural changes in cortical and hippocampal regions. Available data suggest that the new generation of antiepileptic drugs (AEDs) are better tolerated in the elderly population, and may also be the best option in patients with AD and epilepsy.

Conclusion

Further prospective studies involving evaluation of concomitant dementia and epilepsy, neurophysiological findings and biomarkers need to be performed.

Seizures and epileptiform activity in the early stages of Alzheimer disease

IMPORTANCE

Epileptic activity associated with Alzheimer disease (AD) deserves increased attention because it has a harmful impact on these patients, can easily go unrecognized and untreated, and may reflect pathogenic processes that also contribute to other aspects of the illness. We report key features of AD-related seizures and epileptiform activity that are instructive for clinical practice and highlight similarities between AD and transgenic animal models of the disease.

OBJECTIVE

To describe common clinical characteristics and treatment outcomes of patients with amnestic mild cognitive impairment (aMCI) or early AD who also have epilepsy or subclinical epileptiform activity.

DESIGN

Retrospective observational study from 2007 to 2012. SETTING Memory and Aging Center, University of California, San Francisco.

PATIENTS

We studied 54 patients with a diagnosis of aMCI plus epilepsy (n = 12), AD plus epilepsy (n = 35), and AD plus subclinical epileptiform activity (n = 7).

MAIN OUTCOMES AND MEASURES

Clinical and demographic data, electroencephalogram (EEG) readings, and treatment responses to antiepileptic medications.

RESULTS

Patients with aMCI who had epilepsy presented with symptoms of cognitive decline 6.8 years earlier than patients with aMCI who did not have epilepsy (64.3 vs 71.1 years; P = .02). Patients with AD who had epilepsy presented with cognitive decline 5.5 years earlier than patients with AD who did not have epilepsy (64.8 vs 70.3 years; P = .001). Patients with AD who had subclinical epileptiform activity also had an early onset of cognitive decline (58.9 years). The timing of seizure onset in patients with aMCI and AD was nonuniform (P < .001), clustering near the onset of cognitive decline. Epilepsies were most often complex partial seizures (47%) and more than half were nonconvulsive (55%). Serial or extended EEG monitoring appeared to be more effective than routine EEG at detecting interictal and subclinical epileptiform activity. Epileptic foci were predominantly unilateral and temporal. Of the most commonly prescribed antiepileptics, treatment outcomes appeared to be better for lamotrigine and levetiracetam than for phenytoin.

CONCLUSIONS AND RELEVANCE

Common clinical features of patients with aMCI- or AD-associated epilepsy at our center included early age at onset of cognitive decline, early incidence of seizures in the disease course, unilateral temporal epileptic foci detected by serial/extended EEG, transient cognitive dysfunction, and good seizure control and tolerability with lamotrigine and levetiracetam. Careful identification and treatment of epilepsy in such patients may improve their clinical course.

Apparent dose-dependent levetiracetam-induced de novo major depression with suicidal behavior

Levetiracetam (LEV) is a novel antiepileptic drug (AED) approved for the adjunctive treatment of generalized and partial seizures. LEV has no clinically significant drug interactions and has limited adverse effects. The psychiatric adverse effects of LEV include de novo psychosis, affective disorder, and aggression. LEV-induced suicidal behavior has been reported infrequently with a past history of affective disorders. The authors report an apparent dose/concentration-dependent LEV-induced de novo major depression with near fatal suicide attempt in a patient without prior history of affective disorder. Psychiatric evaluation with emphasis on historic/current affective disorders, impulsive-aggressive behaviors, and assessment of risk factors for suicidal behaviors is indicated in treating patients with epilepsy with LEV. Clinicians should consider therapeutic drug monitoring to optimize therapeutic LEV treatment.

The long-term safety of antiepileptic drugs

Antiepileptic drugs (AEDs) are used by millions of people worldwide for the treatment of epilepsy, as well as in many other neurological and psychiatric conditions. They are frequently associated with adverse effects (AEs), which have an impact on the tolerability and success of treatment. Half the people who develop intolerable AEs discontinue treatment early on after initiation, while the majority of people will continue to be exposed to their effects for long periods of time. The long-term safety of AEDs reflects their potential for chronic, cumulative dose effects; rare, but potentially serious late idiosyncratic effects; late, dose-related effects; and delayed, teratogenic or neurodevelopmental effects. These AEs can affect every body system and are usually insidious. With the exception of delayed effects, most other late or chronic AEs are reversible. To date, there is no clear evidence of a carcinogenic effect of AEDs in humans. While physicians are aware of the long-term AEs of old AEDs (the traditional liver enzyme-inducing AEDs and valproate), information about AEs of new AEDs (such as lamotrigine, levetiracetam, oxcarbazepine, topiramate or zonisamide), particularly of their teratogenic effects, has emerged over the years. Sporadic publications have raised issues about AEs of the newer AEDs eslicarbazepine, retigabine, rufinamide, lacosamide and perampanel but their long-term safety profiles may take years to be fully appreciated. Physicians should not only be aware of the late and chronic AEs of AEDs but should systematically enquire and screen for these according to the individual AED AE profile. Care should be taken for individuals with comorbid conditions that may render them more susceptible to specific AEs. Prevention and appropriate management of long-term AED AEs is expected to improve adherence to treatment, quality of life and control of epilepsy.

P/Q-type calcium channel modulators

P/Q-type calcium channels are high-voltage-gated calcium channels contributing to vesicle release at synaptic terminals. A number of neurological diseases have been attributed to malfunctioning of P/Q channels, including ataxia, migraine and Alzheimer's disease. To date, only two specific P/Q-type blockers are known: both are peptides deriving from the spider venom of Agelenopsis aperta, ω-agatoxins. Other peptidic calcium channel blockers with activity at P/Q channels are available, albeit with less selectivity. A number of low molecular weight compounds modulate P/Q-type currents with different characteristics, and some exhibit a peculiar bidirectional pattern of modulation. Interestingly, there are a number of therapeutics in clinical use, which also show P/Q channel activity. Because selectivity as well as the exact mode of action is different between all P/Q-type channel modulators, the interpretation of clinical and experimental data is complicated and needs a comprehensive understanding of their target profile. The situation is further complicated by the fact that information on potency varies vastly in the literature, which may be the result of different experimental systems, conditions or the splice variants of the P/Q channel. This review attempts to provide a comprehensive overview of the compounds available that affect the P/Q-type channel and should help with the interpretation of results of in vitro experiments and animal models. It also aims to explain some clinical observations by implementing current knowledge about P/Q channel modulation of therapeutically used non-selective drugs. Chances and challenges of the development of P/Q channel-selective molecules are discussed.

The efficacy and safety of newer anticonvulsants in patients with dementia

Anticonvulsants are a class of medications that have received considerable interest as possible treatments in patients with behavioural disturbances in dementia. The role of these medications for such a use remains controversial. The current paper reviews the published evidence surrounding the safety and efficacy (i.e. as a behavioural and cognitive treatment) of newer anticonvulsants in patients with dementia. A MEDLINE, International Pharmaceutical Abstracts, PsycINFO and clinicaltrials.gov search through to December 2011 was conducted for anticonvulsants that have received regulatory approval since 1996. Studies reporting behavioural or cognitive outcomes in patients with dementia were included. Nine trials involving only four medications met selection criteria and were included: levetiracetam (n = 4), oxcarbazepine (n = 1), topiramate (n = 2) and zonisamide (n = 2). Levetiracetam may have a role in the treatment of behavioural symptoms in dementia but study limitations substantially hinder the strength of such a recommendation. Oxcarbazepine and topiramate, based on limited data, do not appear to be effective treatments of behavioural symptoms in dementia. A lack of trials do not allow for conclusions to be made regarding zonisamide. From a cognitive standpoint, levetiracetam was the anticonvulsant most examined in patients with dementia, it appears to have less deleterious effects than some anticonvulsants. Limited data are available on the safety of these medications in elderly patients; however, studies completed thus far have demonstrated some adverse events that are more common or problematic with the use of these drugs in this patient population (i.e. somnolence, dizziness, hyponatraemia, weight loss).

Levetiracetam improves verbal memory in high-grade glioma patients

BACKGROUND

Treatment of high-grade glioma (HGG) patients with anti-epileptic drugs (AEDs) has met with various side effects, such as cognitive deterioration. The cognitive effects of both older and newer AEDs in HGG patients are largely unknown. The aim of this study was to determine the effect of older and newer AEDs on cognitive performance in postoperative HGG patients.

METHODS

We selected HGG patients from 3 separate cohorts for use of older, newer, or no AEDs, as they represented distinct treatment eras and provided the opportunity to compare older and newer AEDs. In all 3 cohorts, patients were included within 6 weeks following neurosurgery before the start of postoperative treatment. Cognitive functioning was evaluated by an extensive neuropsychological assessment, executed in 6 cognitive domains (attention, executive functioning, verbal memory, working memory, psychomotor functioning, and information processing speed).

RESULTS

One hundred seventeen patients met the inclusion criteria; 44 patients used no AED, 35 were on monotherapy with a newer AED (all levetiracetam), and 38 were on monotherapy with an older AED (valproic acid or phenytoin). Patients on older and newer AEDs performed equally well as patients not on an AED, and patients on levetiracetam performed even better on verbal memory tests than patients not on an AED. Post-hoc analyses revealed that within the group using older AEDs, patients on valproic acid performed better than patients on phenytoin.

CONCLUSIONS

Neither levetiracetam nor valproic acid was associated with additional cognitive deficits in HGG patients. Both AEDs even appeared to have a beneficial effect on verbal memory in these patients.

Levetiracetam suppresses neuronal network dysfunction and reverses synaptic and cognitive deficits in an Alzheimer's disease model

In light of the rising prevalence of Alzheimer's disease (AD), new strategies to prevent, halt, and reverse this condition are needed urgently. Perturbations of brain network activity are observed in AD patients and in conditions that increase the risk of developing AD, suggesting that aberrant network activity might contribute to AD-related cognitive decline. Human amyloid precursor protein (hAPP) transgenic mice simulate key aspects of AD, including pathologically elevated levels of amyloid-β peptides in brain, aberrant neural network activity, remodeling of hippocampal circuits, synaptic deficits, and behavioral abnormalities. Whether these alterations are linked in a causal chain remains unknown. To explore whether hAPP/amyloid-β-induced aberrant network activity contributes to synaptic and cognitive deficits, we treated hAPP mice with different antiepileptic drugs. Among the drugs tested, only levetiracetam (LEV) effectively reduced abnormal spike activity detected by electroencephalography. Chronic treatment with LEV also reversed hippocampal remodeling, behavioral abnormalities, synaptic dysfunction, and deficits in learning and memory in hAPP mice. Our findings support the hypothesis that aberrant network activity contributes causally to synaptic and cognitive deficits in hAPP mice. LEV might also help ameliorate related abnormalities in people who have or are at risk for AD.

Down syndrome and dementia: seizures and cognitive decline

The objective of this study was to determine the association of seizures and cognitive decline in adults with Down syndrome (DS) and Alzheimer's-type dementia. A retrospective data analysis was carried out following a controlled study of antioxidant supplementation for dementia in DS. Observations were made at baseline and every 6 months for 2 years. Seizure history was obtained from study records. The primary outcome measures comprised the performance-based Severe Impairment Battery (SIB) and Brief Praxis Test (BPT). Secondary outcome measures comprised the informant-based Dementia Questionnaire for Mentally Retarded Persons and Vineland Adaptive Behavior Scales. Because a large proportion of patients with seizures had such severe cognitive decline as to become untestable on the performance measures, time to "first inability to test" was measured. Adjustments were made for the potentially confounding co-variates of age, gender, APOE4 status, baseline cognitive impairment, years since dementia onset at baseline, and treatment assignment. The estimated odds ratio for the time to "first inability to test" on SIB comparing those with seizures to those without is 11.02 (95% CI: 1.59, 76.27), a ratio that is significantly different from 1 (p = 0.015). Similarly, we estimated an odds ratio of 9.02 (95% CI: 1.90, 42.85) on BPT, a ratio also significantly different than 1 (p = 0.006). Results from a secondary analysis of the informant measures showed significant decline related to seizures. We conclude that there is a strong association of seizures with cognitive decline in demented individuals with DS. Prospective studies exploring this relationship in DS are indicated.

Lacosamide for epileptic seizures in patients with co-morbidities and unusual presentations of epilepsy

Numerous patients who are prescribed antiepileptic drugs (AEDs) for epileptic seizures are already receiving other agents for the treatment of co-morbid conditions, which frequently occur alongside epilepsy. This raises additional clinical considerations and makes the use of AEDs with good safety profiles and fewer drug-drug interactions attractive. Second and third-generation anticonvulsant drugs are associated with fewer pharmacological interactions and improved tolerability compared with first-generation drugs. Furthermore, second and third-generation anticonvulsant drugs are associated with linear pharmacokinetic profiles and differing mechanisms of action, making them ideal for pluripathological and polymedicated patients. In this report, we highlight the efficacy of one such agent, lacosamide, in five patients with co-morbidities and unusual presentations of epilepsy, including a patient with paraneoplastic encephalitis caused by microcytic lung carcinoma, one with a brain tumour and one with Alzheimer's disease, as well as a case of catamenial epilepsy and one of refractory convulsive status epilepticus. In all patients, lacosamide was associated with a substantial reduction in seizure frequency and effective control of seizure episodes. Treatment was generally well tolerated in all patients, indicating that lacosamide is an effective treatment option for a variety of patients with epileptic seizures.

Epilepsy in the elderly

Epilepsy is the most common serious neurological disorder in the elderly after stroke and dementia. It may be more important for elderly people because it is intermittent and unpredictable. There is no reliable diagnostic test and so its diagnosis and management requires clinical acumen and experience. The situation is further complicated because the elderly may have many comorbidities and therefore may have many other reasons for losing consciousness. Despite their growing number, there is remarkably little research to underpin the best epilepsy management in the elderly. This article summarizes the scope of epilepsy in elderly people, highlights cerebrovascular and neurodegenerative diseases as the main underlying etiologies, explores the diagnostic challenges in this age group, including the hurdles and processes in their investigation, and examines pertinent clinical management issues.