Older adults with epilepsy demonstrate cognitive impairments compared with patients with amnestic mild cognitive impairment

Association of Seizure Control With Cognition in People With Normal Cognition and Mild Cognitive Impairment

BACKGROUND AND OBJECTIVES

Seizures are common in dementia and associated with accelerated cognitive decline. However, the impact of active vs remote seizures on cognition remains understudied. This study aimed to investigate the impact of active vs remote seizures on cognition in people with normal cognition and mild cognitive impairment (MCI).

METHODS

This longitudinal, multicenter cohort is based on National Alzheimer's Coordinating Center data of participants recruited from 39 Alzheimer's Disease Centers in the United States from September 2005 to December 2021. All participants with normal cognition and MCI and at least 2 visits were included. Primary outcome, that is, cognitive decline, was determined using Clinical Dementia Rating (CDR) from (1) normal-to-impaired (CDR ≥0.5) and (2) MCI-to-dementia (CDR ≥1) groups. The effect of active seizures (over the preceding 12 months), remote seizures (previous seizures but none over the preceding 12 months), and no seizures (controls) on cognition was assessed. Subgroups of chronic seizures at enrollment and new-onset seizures were further analyzed. Cox regression models assessed the risk of all-cause MCI and/or dementia. All models were adjusted for age, sex, education, race, hypertension, and diabetes.

RESULTS

Of the 13,726 participants with normal cognition at enrollment (9,002 [66%] female; median age 71 years), 118 had active seizures and 226 had remote seizures. Of the 11,372 participants with MCI at enrollment (5,605 [49%] female; median age 73 years), 197 had active seizures and 226 had remote seizures. Active seizures were associated with 2.1 times higher risk of cognitive impairment (adjusted hazard ratio [aHR] 2.13, 95% CI 1.60-2.84, p < 0.001) in cognitively healthy adults (median years to decline: active seizures = ∼1, remote seizures = ∼3, no seizures = ∼3) and 1.6 times higher risk of dementia (aHR 1.58, 95% CI 1.24-2.01, p < 0.001) in those with MCI (median years to decline: active seizures = ∼1, remote seizures = ∼2, controls = ∼2). This risk was not observed with remote seizures.

DISCUSSION

In this study, active seizures but not remote seizures were associated with earlier cognitive decline in both cognitively normal adults and those with MCI, independent of other dementia risk factors. Therefore, early identification and management of seizures may present a path to mitigation of cognitive decline in the aging epileptic population. A limitation is that causality cannot be confirmed in our observational longitudinal study.

Alzheimer's disease and epilepsy: Research hotspots for comorbidity in the era of global aging

Neurological conditions such as Alzheimer's disease (AD) and epilepsy share a significant clinical overlap, particularly in the elderly, with each disorder potentiating the risk of the other. This interplay is significant amidst an aging global demographic. The review explores the classical pathologies of AD, including amyloid-beta plaques and hyperphosphorylated tau, and their potential role in the genesis of epilepsy. It also delves into the imbalance of glutamate and gamma-amino butyric acid activities, a key mechanism in epilepsy that may be influenced by AD pathology. The impact of age of onset on comorbidity is examined, with early-onset AD and Down syndrome presenting higher risks of epilepsy. The review suggests that epilepsy might precede cognitive symptoms in AD, indicating a complex interaction. Sleep modulation is highlighted as a factor, with sleep disturbances potentially contributing to AD progression. The necessity for cautious medication management is emphasized due to the cognitive effects of certain antiepileptic drugs. Animal models are recognized for their importance in understanding the relationship between AD and epilepsy, though creating fully representative models presents a challenge. The review concludes by noting the efficacy of medications such as lamotrigine, levetiracetam, and memantine in managing both conditions and suggests the ketogenic diet and cannabidiol as emerging treatment options, warranting further investigation for comprehensive patient care strategies.

Overlapping and distinct phenotypic profiles in Alzheimer's disease and late onset epilepsy: a biologically-based approach

Due to shared hippocampal dysfunction, patients with Alzheimer's dementia and late-onset epilepsy (LOE) report memory decline. Multiple studies have described the epidemiological, pathological, neurophysiological, and behavioral overlap between Alzheimer's Disease and LOE, implying a bi-directional relationship. We describe the neurobiological decline occurring at different spatial in AD and LOE patients, which may explain why their phenotypes overlap and differ. We provide suggestions for clinical recognition of dual presentation and novel approaches for behavioral testing that reflect an "inside-out," or biologically-based approach to testing memory. New memory and language assessments could detect-and treat-memory impairment in AD and LOE at an earlier, actionable stage.

Late-onset epilepsy with cognitive symptoms: Comparison of cognitive and imaging profiles with probable Alzheimer's disease

OBJECTIVE

We aimed to (i) compare the clinical, neuropsychological, and neuroimaging characteristics of unprovoked late-onset epilepsy (LOE) patients with cognitive symptoms against probable Alzheimer's disease (AD) patients; (ii) clarify how neurodegeneration and other processes could be implicated in the cognitive symptoms of unprovoked LOE patients; and (iii) characterize the longitudinal trajectory of unprovoked LOE patients with cognitive symptoms.

METHODS

Twenty-six unprovoked LOE patients with cognitive symptoms and 26 probable AD were retrospectively recruited from epilepsy and memory clinics at a single tertiary referral center. The patients underwent comprehensive clinical, neuropsychological, and 18Fluorodeoxyglucose PET-CT assessments. All LOE patients had clinical follow-up and a subset of 17 patients had repeat neuropsychological assessments.

RESULTS

At baseline, 18% of LOE patients with cognitive symptoms had dementia-range cognitive impairment and one received a diagnosis of probable AD. Compared with the probable AD group, the LOE group did not perform significantly better in global measures of cognition (total ACE-III), neuropsychological tests for fluency, working memory, language, attention, or executive function, but performed better in naming, memory, and visuospatial ability. The commonest patterns of cognitive impairment in the LOE group were frontal and left temporal, whereas all AD patients exhibited parietotemporal patterns. The AD group had more 18Fluorodeoxyglucose PET-CT hypometabolism in the parietal and occipital, but not the temporal and frontal lobes. During the 3.0 ± 3.2 years follow-up, improved seizure frequency in the LOE group covaried with improved total ACE-III score, there was no further conversion to probable AD and no group-level cognitive decline.

CONCLUSION

Unprovoked LOE patients with cognitive symptoms had varying severities of cognitive impairment, and different patterns of cognitive and imaging abnormalities compared with AD patients. They were rarely diagnosed with probable AD at presentation or follow-up. Cognitive outcome in LOE may be related to seizure control. Cerebral small vessel disease may play a role in LOE-associated cognitive impairment.

Cognitive dysfunction in drug-naïve late-onset temporal lobe epilepsy

OBJECTIVES

To evaluate cognitive functions including memory in middle-aged and elderly patients with antiseizure drug-naïve late-onset temporal lobe epilepsy (TLE).

METHODS

We performed assessments with the Wechsler Adult Intelligence Scale-III (WAIS-III) and Wechsler Memory Scale-Revised (WMS-R) in 26 antiseizure drug-naïve patients with late-onset TLE, in comparison to 30 healthy subjects. We investigated the relationships between these cognitive function scores and clinical characteristics, seizure frequency, and frequency of interictal epileptic discharges (IEDs).

RESULTS

Patients with epilepsy had a significantly lower score than healthy controls in the verbal intelligence quotient (IQ), the performance IQ, and full-scale IQ in intelligence testing. Patients showed significantly decrease in the verbal memory scores, visual memory scores, general memory scores, and delayed recall scores compared with those in the control subjects. Delayed recall scores were significantly negatively correlated with recent seizure frequency and the total IEDs count per minute, but not with age of onset or duration of illness.

SIGNIFICANCE

Patients with antiseizure drug-naïve late-onset TLE displayed cognitive deficits including the domains of memory by using standard clinical neuropsychological test. Patients with late-onset epilepsy need to be considered for cognitive dysfunction at the time of diagnosis of TLE because they may have their daily life and work affected not only by epileptic seizures but also by cognitive deficits. Appearance of seizures and EEG abnormalities may affect the memory function in patients with late-onset TLE.

Cognitive phenotypes in late-onset epilepsy: results from the atherosclerosis risk in communities study

Introduction

Cognitive phenotyping is a widely used approach to characterize the heterogeneity of deficits in patients with a range of neurological disorders but has only recently been applied to patients with epilepsy. In this study, we identify cognitive phenotypes in older adults with late-onset epilepsy (LOE) and examine their demographic, clinical, and vascular profiles. Further, we examine whether specific phenotypes pose an increased risk for progressive cognitive decline.

Methods

Participants were part of the Atherosclerosis Risk in Communities Study (ARIC), a prospective longitudinal community-based cohort study of 15,792 individuals initially enrolled in 1987-1989. LOE was identified from linked Centers for Medicare and Medicaid Services claims data. Ninety-one participants with LOE completed comprehensive testing either prior to or after seizure onset as part of a larger cohort in the ARIC Neurocognitive Study in either 2011-2013 or 2016-2017 (follow-up mean = 4.9 years). Cognitive phenotypes in individuals with LOE were derived by calculating test-level impairments for each participant (i.e., ≤1 SD below cognitively normal participants on measures of language, memory, and executive function/processing speed); and then assigning participants to phenotypes if they were impaired on at least two tests within a domain. The total number of impaired domains was used to determine the cognitive phenotypes (i.e., Minimal/No Impairment, Single Domain, or Multidomain).

Results

At our baseline (Visit 5), 36.3% met criteria for Minimal/No Impairment, 35% for Single Domain Impairment (with executive functioning/ processing speed impaired in 53.6%), and 28.7% for Multidomain Impairment. The Minimal/No Impairment group had higher education and occupational complexity. There were no differences in clinical or vascular risk factors across phenotypes. Of those participants with longitudinal data (Visit 6; n = 24), 62.5% declined (i.e., progressed to a more impaired phenotype) and 37.5% remained stable. Those who remained stable were more highly educated compared to those that declined.

Discussion

Our results demonstrate the presence of identifiable cognitive phenotypes in older adults with LOE. These results also highlight the high prevalence of cognitive impairments across domains, with deficits in executive function/processing speed the most common isolated impairment. We also demonstrate that higher education was associated with a Minimal/No Impairment phenotype and lower risk for cognitive decline over time.

Association of Dementia Risk With Focal Epilepsy and Modifiable Cardiovascular Risk Factors

Importance

Epilepsy has been associated with cognitive impairment and potentially dementia in older individuals. However, the extent to which epilepsy may increase dementia risk, how this compares with other neurological conditions, and how modifiable cardiovascular risk factors may affect this risk remain unclear.

Objective

To compare the differential risks of subsequent dementia for focal epilepsy compared with stroke and migraine as well as healthy controls, stratified by cardiovascular risk.

Design, Setting, and Participants

This cross-sectional study is based on data from the UK Biobank, a population-based cohort of more than 500 000 participants aged 38 to 72 years who underwent physiological measurements and cognitive testing and provided biological samples at 1 of 22 centers across the United Kingdom. Participants were eligible for this study if they were without dementia at baseline and had clinical data pertaining to a history of focal epilepsy, stroke, or migraine. The baseline assessment was performed from 2006 to 2010, and participants were followed up until 2021.

Exposures

Mutually exclusive groups of participants with epilepsy, stroke, and migraine at baseline assessment and controls (who had none of these conditions). Individuals were divided into low, moderate, or high cardiovascular risk groups based on factors that included waist to hip ratio, history of hypertension, hypercholesterolemia, diabetes, and smoking pack-years.

Main Outcomes and Measures

Incident all-cause dementia; measures of executive function; and brain total hippocampal, gray matter, and white matter hyperintensity volumes.

Results

Of 495 149 participants (225 481 [45.5%] men; mean [SD] age, 57.5 [8.1] years), 3864 had a diagnosis of focal epilepsy only, 6397 had a history of stroke only, and 14 518 had migraine only. Executive function was comparable between participants with epilepsy and stroke and worse than the control and migraine group. Focal epilepsy was associated with a higher risk of developing dementia (hazard ratio [HR], 4.02; 95% CI, 3.45 to 4.68; P < .001), compared with stroke (HR, 2.56; 95% CI, 2.28 to 2.87; P < .001), or migraine (HR, 1.02; 95% CI, 0.85 to 1.21; P = .94). Participants with focal epilepsy and high cardiovascular risk were more than 13 times more likely to develop dementia (HR, 13.66; 95% CI, 10.61 to 17.60; P < .001) compared with controls with low cardiovascular risk. The imaging subsample included 42 353 participants. Focal epilepsy was associated with lower hippocampal volume (mean difference, -0.17; 95% CI, -0.02 to -0.32; t = -2.18; P = .03) and lower total gray matter volume (mean difference, -0.33; 95% CI, -0.18 to -0.48; t = -4.29; P < .001) compared with controls. There was no significant difference in white matter hyperintensity volume (mean difference, 0.10; 95% CI, -0.07 to 0.26; t = 1.14; P = .26).

Conclusions and Relevance

In this study, focal epilepsy was associated with a significant risk of developing dementia, to a greater extent than stroke, which was magnified substantially in individuals with high cardiovascular risk. Further findings suggest that targeting modifiable cardiovascular risk factors may be an effective intervention to reduce dementia risk in individuals with epilepsy.

The Impact of Epilepsy on Complication Rates After Total Joint Arthroplasty: A Propensity Score-Matched Cohort Study

BACKGROUND

It is unclear how epilepsy may affect total joint arthroplasty outcomes. The purpose of this study is to analyze the impact of epilepsy on prosthesis-related complications following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

A retrospective cohort study was conducted using a national database. Patients who have epilepsy underwent a primary THA (n = 6,981) and TKA (n = 4,987) and were matched 1:4 (THA, n = 27,924; TKA, n = 19,948). Rates of low-energy falls and prosthesis-related complications within 2 years postoperatively were compared for patients who did and did not have epilepsy with multivariable logistic regression.

RESULTS

After primary TKA, patients who have epilepsy exhibited significantly higher rates of aseptic revision (4.3% versus 3.5%, odds ratio [OR] 1.21, P = .017) and revision for prosthetic joint infection (1.8% versus 1.3%, OR 1.29, P = .041). THA patients who have epilepsy exhibited significantly higher rates of prosthetic dislocation (3.2% versus 1.9%, OR 1.54, P < .001), periprosthetic fracture (2.2% versus 0.8%, OR 2.39, P < .001), and aseptic loosening (1.7% versus 1.1%, OR 1.40, P = .002). Rates of low-energy falls within 2 years after TKA (14.1% versus 6.4%, OR 2.19, P < .001) and THA (33.6% versus 7.5%, OR 5.95, P < .001) were also significantly higher for patients who have epilepsy.

CONCLUSION

Epilepsy was associated with significantly higher rates of falls (P < .001) and prosthesis-related complications after primary THA (P < .05) and TKA (P < .05). Precautions should be implemented in this population during intraoperative and perioperative decision-making to reduce complication risk.

LEVEL OF EVIDENCE

Level III.

Cognitive impairment in people with epilepsy: Montreal Cognitive Assessment (MoCA) as a screening tool

OBJECTIVES

Although cognitive impairment is common in people with epilepsy, it is often neglected in outpatient clinics. MoCA is a simple and reliable test, which was validated for the cognitive screening of Alzheimer's and vascular dementia. The aim of our study was to evaluate MoCA as a tool for a cognitive screening of people with epilepsy.

METHODS

Our study included 50 people with epilepsy and 46 healthy individuals. All participants took the Slovenian version of the MoCA. Mean age, education and MoCA scores were compared between the two groups.

RESULTS

There was no significant difference between people with epilepsy and the controls in age (47.6, SD 18.1 vs 50.9, SD 14.0 years) or education (12.8, SD 2.8 vs 13.4, SD 2.8 years). People with epilepsy had significantly lower total MoCA scores than did the controls (23.3, SD 4.5 vs 27.5, SD 1.9 points; p < 0.001).

CONCLUSIONS

People with epilepsy achieved a lower score in several cognitive domains compared to the control group. MoCA can be used as an appropriate screening tool for cognitive impairment in people with epilepsy in the outpatient clinic. For a more accurate evaluation, neuropsychological assessments should be used.

Impaired Behavioral Pattern Separation in Refractory Temporal Lobe Epilepsy and Mild Cognitive Impairment

OBJECTIVE

Episodic memory impairment and hippocampal pathology are hallmark features of both temporal lobe epilepsy (TLE) and amnestic mild cognitive impairment (aMCI). Pattern separation (PS), which enables the distinction between similar but unique experiences, is thought to contribute to successful encoding and retrieval of episodic memories. Impaired PS has been proposed as a potential mechanism underling episodic memory impairment in aMCI, but this association is less established in TLE. In this study, we examined behavioral PS in patients with TLE and explored whether profiles of performance in TLE are similar to aMCI.

METHOD

Patients with TLE, aMCI, and age-matched, healthy controls (HCs) completed a modified recognition task that relies on PS for the discrimination of highly similar lure items, the Mnemonic Similarity Task (MST). Group differences were evaluated and relationships between clinical characteristics, California Verbal Learning Test-Second Edition scores, and MST performance were tested in the TLE group.

RESULTS

Patients with TLE and aMCI demonstrated poorer PS performance relative to the HCs, but performance did not differ between the two patient groups. Neither the side of seizure focus nor having hippocampal sclerosis affected performance in TLE. However, TLE patients with clinically defined memory impairment showed the poorest performance.

CONCLUSION

Memory performance on a task that relies on PS was disrupted to a similar extent in TLE and aMCI. The MST could provide a clinically useful tool for measuring hippocampus-dependent memory impairments in TLE and other neurological disorders associated with hippocampal damage.

Mechanisms Involved in Epileptogenesis in Alzheimer's Disease and Their Therapeutic Implications

Epilepsy and Alzheimer's disease (AD) incidence increases with age. There are reciprocal relationships between epilepsy and AD. Epilepsy is a risk factor for AD and, in turn, AD is an independent risk factor for developing epilepsy in old age, and abnormal AD biomarkers in PET and/or CSF are frequently found in late-onset epilepsies of unknown etiology. Accordingly, epilepsy and AD share pathophysiological processes, including neuronal hyperexcitability and an early excitatory-inhibitory dysregulation, leading to dysfunction in the inhibitory GABAergic and excitatory glutamatergic systems. Moreover, both β-amyloid and tau protein aggregates, the anatomopathological hallmarks of AD, have proepileptic effects. Finally, these aggregates have been found in the resection material of refractory temporal lobe epilepsies, suggesting that epilepsy leads to amyloid and tau aggregates. Some epileptic syndromes, such as medial temporal lobe epilepsy, share structural and functional neuroimaging findings with AD, leading to overlapping symptomatology, such as episodic memory deficits and toxic synergistic effects. In this respect, the existence of epileptiform activity and electroclinical seizures in AD appears to accelerate the progression of cognitive decline, and the presence of cognitive decline is much more prevalent in epileptic patients than in elderly patients without epilepsy. Notwithstanding their clinical significance, the diagnosis of clinical seizures in AD is a challenge. Most are focal and manifest with an altered level of consciousness without motor symptoms, and are often interpreted as cognitive fluctuations. Finally, despite the frequent association of epilepsy and AD dementia, there is a lack of clinical trials to guide the use of antiseizure medications (ASMs). There is also a potential role for ASMs to be used as disease-modifying drugs in AD.

Clinical and Instrumental Characterization of Patients With Late-Onset Epilepsy

Epilepsy is classically considered a childhood disease. However, it represents the third most frequent neurological condition in the elderly, following stroke, and dementia. With the progressive aging of the general population, the number of patients with Late-Onset Epilepsy (LOE) is constantly growing, with important economic and social consequences, in particular for the more developed countries where the percentage of elderly people is higher. The most common causes of LOE are structural, mainly secondary to cerebrovascular or infectious diseases, brain tumors, trauma, and metabolic or toxic conditions. Moreover, there is a growing body of evidence linking LOE with neurodegenerative diseases, particularly Alzheimer's disease (AD). However, despite a thorough characterization, the causes of LOE remain unknown in a considerable portion of patients, thus termed as Late-Onset Epilepsy of Unknown origin (LOEU). In order to identify the possible causes of the disease, with an important impact in terms of treatment and prognosis, LOE patients should always undergo an exhaustive phenotypic characterization. In this work, we provide a detailed review of the main clinical and instrumental techniques for the adequate characterization of LOE patients in the clinical practice. This work aims to provide an easy and effective tool that supports routine activity of the clinicians facing LOE.

Epilepsy-associated comorbidities among adults: A plausible therapeutic role of gut microbiota

Epilepsy is a debilitating disorder that affects about 70 million people in the world currently. Most patients with epilepsy (PWE) often reported at least one type of comorbid disorder. These may include neuropsychiatric disorders, cognitive deficits, migraine, cardiovascular dysfunction, systemic autoimmune disorders and others. Current treatment strategies against epilepsy-associated comorbidities have been based on targeting each disorder separately with either anti-seizure medications (ASMs), anti-inflammatories or anti-depressant drugs, which have often given inconsistent and ineffective results. Gut dysbiosis may be a common pathological pathway between epilepsy and its comorbid disorders, and thus may serve as a possible intervention target. Therefore, this narrative review aimed to elucidate the potential pathological and therapeutic role of the gut microbiota in adult epilepsy-associated comorbidities. This review noticed a scarcity in the current literature on studies investigating the direct role of the gut microbiota in relation to epilepsy-associated comorbidities. Nevertheless, gut dysbiosis have been implicated in both epilepsy and its associated comorbidities, with similarities seen in the imbalance of certain gut microbiota phyla (Firmicutes), but differences seen in the mechanism of action. Current gut-related interventions such as probiotics have been consistently reported across studies to provide beneficial effects in correcting gut dysbiosis and improving various disorders, independent of epilepsy. However, whether these beneficial effects may translate towards epilepsy-associated comorbidities have yet to be determined. Thus, future studies determining the therapeutic potential of gut microbiota interventions in PWE with epilepsy-associated comorbidities may effectively improve their quality of life.

Cognitive Impairment in People with Epilepsy

People with epilepsy frequently have cognitive impairment. The majority of cognitive problems is influenced by a variety of interlinked factors, including the early onset of epilepsy and the frequency, intensity and duration of seizures, along with the anti-epileptic drug treatment. With a systematic review, we investigate significant factors about the cognitive impairment in epilepsy. Most cognitive problems in adult people with epilepsy include memory, attention and executive function deficits. However, which cognitive area is mainly affected highly depends on the location of epileptic activity. Moreover, modifications in signalling pathways and neuronal networks have an essential role in both the pathophysiology of epilepsy and in the mechanism responsible for cognitive impairment. Additionally, studies have shown that the use of polytherapy in the treatment of epilepsy with anti-epileptic drugs (AEDs) heightens the risk for cognitive impairment. It can be challenging to distinguish the contribution of each factor, because they are often closely intertwined.

Theory of Mind and Empathy in Adults With Epilepsy: A Meta-Analysis

Mounting evidence suggests that social cognitive abilities [including theory of mind (ToM) and empathy] are impaired in adult patients with epilepsy. Although the deficits in overall ToM in epilepsy have been documented well, the effects of epilepsy on empathic ability and specific subcomponents of ToM remain unclear. The primary aim of this study was to provide the first meta-analytic integration of ToM and empathy in adult patients with epilepsy, and to decompose these constructs to clearly differentiate their distinct (cognitive ToM and affective empathy) and overlapping (affective ToM/cognitive empathy) components. This meta-analysis included 28 studies. Adult patients with temporal lobe epilepsy (TLE) and frontal lobe epilepsy (FLE) showed impairments in cognitive ToM and affective ToM/cognitive empathy compared to the healthy controls (HCs); no group differences were identified for affective empathy. Besides, cognitive ToM was impaired in adult patients with idiopathic generalized epilepsy (IGE) and focal seizures (caused by epileptogenic foci) outside the temporal and frontal lobes (extra-TLE/FLE) and no group differences were evident for affective ToM/cognitive empathy compared to the HCs. Moreover, relative to the HCs, no group differences were identified for affective empathy in adult patients with IGE. Additionally, no (statistically) significant difference was observed between the magnitude of ToM/empathy impairment in adult patients who underwent and those who did not undergo epilepsy surgery. These quantitative findings suggest differential impairment of the core aspects of social cognitive processing in adult patients with epilepsy, which may contribute to the development of structured cognitive interventions (i.e., social cognitive training) for adult patients with epilepsy.

Amyloid-β: a potential link between epilepsy and cognitive decline

People with epilepsy - in particular, late-onset epilepsy of unknown aetiology - have an elevated risk of dementia, and seizures have been detected in the early stages of Alzheimer disease (AD), supporting the concept of an epileptic AD prodrome. However, the relationship between epilepsy and cognitive decline remains controversial, with substantial uncertainties about whether epilepsy drives cognitive decline or vice versa, and whether shared pathways underlie both conditions. Here, we review evidence that amyloid-β (Aβ) forms part of a shared pathway between epilepsy and cognitive decline, particularly in the context of AD. People with epilepsy show an increased burden of Aβ pathology in the brain, and Aβ-mediated epileptogenic alterations have been demonstrated in experimental studies, with evidence suggesting that Aβ pathology might already be pro-epileptogenic at the soluble stage, long before plaque deposition. We discuss the hypothesis that Aβ mediates - or is at least a major determinant of - a continuum spanning epilepsy and cognitive decline. Serial cognitive testing and assessment of Aβ levels might be worthwhile to stratify the risk of developing dementia in people with late-onset epilepsy. If seizures are a clinical harbinger of dementia, people with late-onset epilepsy could be an ideal group in which to implement preventive or therapeutic strategies to slow cognitive decline.

Psychiatric and cognitive characteristics of older adults admitted to a Video-EEG monitoring (VEM) unit

OBJECTIVE

To compare the clinical, psychiatric, and cognitive characteristics of older with younger patients presenting to a video-EEG monitoring (VEM) unit.

METHOD

This was a retrospective case-control study involving patients admitted for VEM over a two-year period (from April 2018 to April 2020) at two comprehensive epilepsy units. Patients were categorized into an older (≥60 years) and a younger (<60 years) group. Younger patients were individually matched to older adults to form a matched younger group. Diagnosis was determined by a consensus opinion of epileptologists, neurologists, and neuropsychiatrists. The main diagnostic categories were epilepsy, psychogenic nonepileptic seizures (PNES), and 'other' diagnosis (non-diagnostic and other nonepileptic diagnoses). Clinical psychiatric diagnoses were obtained from neuropsychiatric reports. Objective cognitive function was measured with the Neuropsychiatry Unit Cognitive Assessment Tool (NUCOG). Subjective cognitive function was assessed using the Quality of Life in Epilepsy Inventory-89 (QOLIE-89) cognitive subscales.

RESULTS

Five-hundred and thirty three patients (71 older, 462 younger) aged 16-91 years were admitted to the VEM unit during the study period. There was a diagnosis of focal epilepsy in 55% of the older group and 48% of the younger group, generalized epilepsy in 3% of the older group and 10% of the younger group, and 'other' in 32% of the older group and 19% of the younger group. Ten percent (2 males and 5 females) of the older group were diagnosed with PNES compared to 22% of the younger group (p = 0.016). A depressive disorder was diagnosed in 34% of the older group and 24% of the younger group (p = 0.20). An anxiety disorder was diagnosed in 15% of the older group and 25% of the younger group (p = 0.15). Mild neurocognitive disorder was more common in the older group (34%) compared to the matched younger group (34% vs 3%, p < 0.001). The older group had lower mean NUCOG scores compared to the matched younger group (79.49 vs 87.73, p = <0.001). There was no evidence for a relationship between mean NUCOG score and overall subjective cognitive difficulties for the older group (r = 0.03, p = 0.83). Among older adults, those diagnosed with PNES had more experiences of childhood trauma. Measures of dissociation, depression, or general anxiety did not differ between PNES and non-PNES diagnoses in the older group.

CONCLUSION

Psychiatric comorbidities are common among older adults admitted for VEM. The psychological impact of epilepsy and risk factors for PNES seen in younger patients are also applicable in the older group. The older group demonstrated more cognitive impairments than the younger group, although these were usually unrecognized by individuals. Older adults admitted to VEM will benefit from psychiatric and neuropsychological input to ensure a comprehensive care approach to evaluation and management.

Atrophy and cognitive profiles in older adults with temporal lobe epilepsy are similar to mild cognitive impairment

Epilepsy incidence and prevalence peaks in older adults yet systematic studies of brain ageing and cognition in older adults with epilepsy remain limited. Here, we characterize patterns of cortical atrophy and cognitive impairment in 73 older adults with temporal lobe epilepsy (>55 years) and compare these patterns to those observed in 70 healthy controls and 79 patients with amnestic mild cognitive impairment, the prodromal stage of Alzheimer's disease. Patients with temporal lobe epilepsy were recruited from four tertiary epilepsy surgical centres; amnestic mild cognitive impairment and control subjects were obtained from the Alzheimer's Disease Neuroimaging Initiative database. Whole brain and region of interest analyses were conducted between patient groups and controls, as well as between temporal lobe epilepsy patients with early-onset (age of onset <50 years) and late-onset (>50 years) seizures. Older adults with temporal lobe epilepsy demonstrated a similar pattern and magnitude of medial temporal lobe atrophy to amnestic mild cognitive impairment. Region of interest analyses revealed pronounced medial temporal lobe thinning in both patient groups in bilateral entorhinal, temporal pole, and fusiform regions (all P < 0.05). Patients with temporal lobe epilepsy demonstrated thinner left entorhinal cortex compared to amnestic mild cognitive impairment (P = 0.02). Patients with late-onset temporal lobe epilepsy had a more consistent pattern of cortical thinning than patients with early-onset epilepsy, demonstrating decreased cortical thickness extending into the bilateral fusiform (both P < 0.01). Both temporal lobe epilepsy and amnestic mild cognitive impairment groups showed significant memory and language impairment relative to healthy control subjects. However, despite similar performances in language and memory encoding, patients with amnestic mild cognitive impairment demonstrated poorer delayed memory performances relative to both early and late-onset temporal lobe epilepsy. Medial temporal lobe atrophy and cognitive impairment overlap between older adults with temporal lobe epilepsy and amnestic mild cognitive impairment highlights the risks of growing old with epilepsy. Concerns regarding accelerated ageing and Alzheimer's disease co-morbidity in older adults with temporal lobe epilepsy suggests an urgent need for translational research aimed at identifying common mechanisms and/or targeting symptoms shared across a broad neurological disease spectrum.

Best care for older people with epilepsy: A scoping review

There are two peaks of diagnosis of epilepsy: in childhood and in people over 65. Older people may have complex needs like co-morbidity, polypharmacy, frailty, and social isolation. This scoping review focusses on the care of older people with epilepsy beyond diagnosis and medical treatment. We sought to identify areas within the UK health service needing development either in clinical practice or through further research. The search returned 4864 papers with 33 papers included in the review. The papers were grouped into psychosocial, self-management and services themes. Only one randomised controlled trial was found. Research was mainly based on cohort and case-control studies. Older people require more information to self-manage epilepsy and more psychological support to help with symptoms of anxiety and depression. People reported experiencing stigma and a reluctance to disclose their condition. This may increase the risk of isolation and difficulties in managing epilepsy. Studies reported that older people are referred less to neurologists, suggesting there may be a gap in care provision compared to younger people. Generalist health professionals may be better placed to provide holistic care, but they may need additional training to alleviate uncertainties in managing epilepsy. Care plans could help provide information, particularly for co-morbidity, but few had one. Our findings highlight psychological and self-management needs for managing epilepsy in older people. Health service staff may require upskilling to shift epilepsy management from neurologists to generalists. More research is needed regarding psychological and self-management interventions, particularly in the form of randomised controlled trials.

Diagnosing cognitive disorders in older adults with epilepsy

OBJECTIVE

To characterize the nature and prevalence of cognitive disorders in older adults with temporal lobe epilepsy (TLE) and compare their cognitive profiles to patients with amnestic mild cognitive impairment (ie, aMCI).

METHODS

Seventy-one older patients with TLE, 77 aMCI, and 69 normal aging controls (NACs), all 55-80 years of age, completed neuropsychological measures of memory, language, executive function, and processing speed. An actuarial neuropsychological method designed to diagnose MCI was applied to individual patients to identify older adults with TLE who met diagnostic criteria for MCI (TLE-MCI). A linear classifier was performed to evaluate how well the diagnostic criteria differentiated patients with TLE-MCI from aMCI. In TLE, the contribution of epilepsy-related and vascular risk factors to cognitive impairment was evaluated using multiple regression.

RESULTS

Forty-three TLE patients (60%) met criteria for TLE-MCI, demonstrating marked deficits in both memory and language. When patients were analyzed according to age at seizure onset, 63% of those with an early onset (<50 years) versus 56% of those with late onset (≥ 50 years) met criteria for TLE-MCI. A classification model between TLE-MCI and aMCI correctly classified 81.1% (90.6% specificity, 61.3% sensitivity) of the cohort based on neuropsychological scores. Whereas TLE-MCI showed greater deficits in language relative to aMCI, patients with aMCI showed greater rapid forgetting on memory measures. Both epilepsy-related risk factors and the presence of leukoaraiosis on MRI contributed to impairment profiles in TLE-MCI.

SIGNIFICANCE

Cognitive impairment is a common comorbidity in epilepsy and it presents in a substantial number of older adults with TLE. Although the underlying etiologies are unknown in many patients, the TLE-MCI phenotype may be secondary to an accumulation of epilepsy and vascular risk factors, signal the onset of a neurodegenerative disease, or represent a combination of factors.

Cognitive-Linguistic Functions in Adults With Epilepsy: Preliminary Electrophysiological and Behavioral Findings

Purpose Cognition and language difficulties are frequently reported in both children and adults with epilepsy. The majority of the existing research has focused on pediatric epilepsy, documenting impairments in learning, academics, and social-emotional functioning. In comparison, language deficits in younger and older adults with epilepsy have received less empirical attention. Given recently identified limitations in the extant literature regarding assessing epilepsy-related language problems in adults (Dutta et al., 2018), the current exploratory study described in this research note investigated the cognitive-linguistic abilities of adults with focal or generalized types of epilepsy. Method Twelve participants with epilepsy and 11 age- and education-matched healthy controls completed a cognitive-linguistic test battery. Event-related potential (ERP) procedures were also employed to assess the integrity of neural activity supporting psycholinguistic processing in both groups using a lexical decision task. Results No significant performance differences between epilepsy and healthy control groups were noted on basic language tasks; however, group differences were evident on the more complex language measures, including spoken discourse. Even though both groups performed the lexical decision task similarly in terms of accuracy, individuals with epilepsy demonstrated longer reaction times and some atypical ERP characteristics compared to controls. Conclusion The cognitive-linguistic assessment and ERP findings suggested that, compared to neurotypical adults, individuals with epilepsy demonstrate slower processing times and greater difficulty with high-level language and spoken discourse production, despite performing within typical limits on basic language tests. Preliminary results from this research are significant in providing new knowledge about language functioning in adults with epilepsy.

Factors Affecting Cognition and Depression in Adult Patients with Epilepsy

Background and Purpose

Epilepsy patients are more likely to experience depressive symptoms and cognitive impairment compared to individuals in the general population. As the reasons for this are not definitively known, we sought to determine what factors correlate most strongly with cognition and a screening test for depression in epilepsy patients.

Methods

Our study population included 379 adult patients diagnosed with epilepsy or seizure in our neurology clinic. We collected detailed demographic and clinical data during patient visits using structured clinical documentation support tools that we have built within our commercial electronic medical records system (Epic), including a depression score (Neurological Disorders Depression Inventory for Epilepsy, NDDIE) and cognition score test measures (specifically in this study, Mini-Mental State Examination [MMSE]). Medication, age, gender, body mass index, duration of epilepsy, seizure frequency, current number of anti-epileptic medications, years of education were assessed in relation to baseline score as well as change in score from initial visit to first annual follow-up.

Results

Of the analyzed factors, two statistically significant associations were found after correction for multiple testing. Male gender and lower anti-seizure medication count were associated with better mood, as assessed by NDDIE score, at initial visit. Specifically, male gender was associated with a 1.3 decrease in NDDIE and for each additional anti-seizure medication, there was an associated 1.2 increase in NDDIE.

Conclusions

However, these factors were not associated with change in NDDIE score from initial to first annual follow-up visit. These findings, although interesting, are preliminary. Additionally, these findings were based on a homogenous (mainly Caucasian) clinic-based population and detailed information on previous medication use was lacking. Further work is needed to replicate these findings and to understand any mechanisms that may explain these associations.

Epilepsy and aging

The intersection of epilepsy and aging has broad, significant implications. Substantial increases in seizures occur both in the elderly population, who are at a higher risk of developing new-onset epilepsy, and in those with chronic epilepsy who become aged. There are notable gaps in our understanding of aging and epilepsy at the basic and practical levels, which have important consequences. We are in the early stages of understanding the complex relationships between epilepsy and other age-related brain diseases such as stroke, dementia, traumatic brain injury (TBI), and cancer. Furthermore, the clinician must recognize that the presentation and treatment of epilepsy in the elderly are different from those of younger populations. Given the developing awareness of the problem and the capabilities of contemporary, multidisciplinary approaches to advance understanding about the biology of aging and epilepsy, it is reasonable to expect that we will unravel some of the intricacies of epilepsy in the elderly; it is also reasonable to expect that these gains will lead to further improvements in our understanding and treatment of epilepsy for all age groups.

Late-Onset Epilepsy With Unknown Etiology: A Pilot Study on Neuropsychological Profile, Cerebrospinal Fluid Biomarkers, and Quantitative EEG Characteristics

Introduction: Despite the fact that epilepsy has been associated with cognitive decline, neuropsychological, neurobiological, and neurophysiological features in patients with late-onset epilepsy of unknown etiology (LOEU) are still unknown. This cross-sectional study aims to investigate the neuropsychological profile, cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD), and resting-state quantitative electroencephalographic (qEEG) cortical rhythms in LOEU patients with mild cognitive impairment (LOEU-MCI) and with normal cognition (LOEU-CN), compared to non-epileptic MCI (NE-MCI) and cognitively normal (CN) controls. Methods: Consecutive patients in two clinical Units diagnosed with LOEU-CN (19), LOEU-MCI (27), and NE-MCI (21) were enrolled, and compared to age and sex-matched cognitively normal subjects CN (11). Patients underwent standardized comprehensive neuropsychological evaluation and CSF core AD biomarkers assessment (i.e., CSF Aβ42, phospho-tau and total tau, classified through A/T/(N) system). Recordings of resting-state eyes-closed electroencephalographic (EEG) rhythms were collected and cortical source estimation of delta (<4 Hz) to gamma (>30 Hz) bands with exact Low Resolution Electromagnetic Tomography (eLORETA) was performed. Results: Most LOEU patients had an MCI status at seizure onset (59%). Patients with LOEU-MCI performed significantly worse on measures of global cognition, visuo-spatial abilities, and executive functions compared to NE-MCI patients (p < 0.05). Regarding MCI subtypes, multiple-domain MCI was 3-fold more frequent in LOEU-MCI than in NE-MCI patients (OR 3.14, 95%CI 0.93-10.58, p = 0.06). CSF Aβ42 levels were lower in the LOEU-MCI compared with the LOEU-CN group. Finally, parietal and occipital sources of alpha (8-12 Hz) rhythms were less active in the LOEU-MCI than in the NE-MCI and CN groups, while the opposite was true for frontal and temporal cortical delta sources. Discussion: MCI status was relatively frequent in LOEU patients, involved multiple cognitive domains, and might have been driven by amyloidosis according to CSF biomarkers. LOEU-MCI status was associated with abnormalities in cortical sources of EEG rhythms related to quiet vigilance. Future longitudinal studies should cross-validate our findings and test the predictive value of CSF and EEG variables.

Epilepsy in older people

Globally, as populations age there will be challenges and opportunities to deliver optimal health care to senior citizens. Epilepsy, a condition characterised by spontaneous recurrent seizures, is common in older adults (aged >65 years) and yet has received comparatively little attention in this age group. In this Review, we evaluate the underlying causes of epilepsy in older people, explore difficulties in establishing a diagnosis of epilepsy in this population, discuss appropriate antiseizure medications, and evaluate potential surgical treatment options. We consider cognitive, psychological, and psychosocial comorbidities and the effect that epilepsy might have on an older person's broader social or care network in high-income versus middle-income and low-income countries. We emphasise the need for clinical trials to be more inclusive of older people with epilepsy to help inform therapeutic decision making and discuss whether measures to improve vascular risk factors might be an important strategy to reduce the probability of developing epilepsy.

Stage-dependent involvement of ADAM10 and its significance in epileptic seizures

The prevalence of epileptic seizures in Alzheimer's disease (AD) has attracted an increasing amount of attention in recent years, and many cohort studies have found several risk factors associated with the genesis of seizures in AD. Among these factors, young age and severe dementia are seemingly contradictory and independent risk factors, indicating that the pathogenesis of epileptic seizures is, to a certain extent, stage‐dependent. A disintegrin and metalloproteinase domain‐containing protein 10 (ADAM10) is a crucial α‐secretase responsible for ectodomain shedding of its substrates; thus, the function of this protein depends on the biological effects of its substrates. Intriguingly, transgenic models have demonstrated ADAM10 to be associated with epilepsy. Based on the biological effects of its substrates, the potential pathogenic roles of ADAM10 in epileptic seizures can be classified into amyloidogenic processes in the ageing stage and cortical dysplasia in the developmental stage. Therefore, ADAM10 is reviewed here as a stage‐dependent modulator in the pathogenesis of epilepsy. Current data regarding ADAM10 in epileptic seizures were collected and reviewed for potential pathogenic roles (ie amyloidogenic processes and cortical dysplasia) and regulatory mechanisms (ie transcriptional and posttranscriptional regulation). These findings are then discussed in terms of the significance of the stage‐dependent functions of ADAM10 in epilepsy. Several potential targets for seizure control, such as candidate transcription factors and microRNAs that regulate ADAM10, as well as potential genetic screening tools for the early recognition of cortical dysplasia, have been suggested but must be studied in more detail.

Seizure frequency and risk of cognitive impairment in people living with epilepsy in a sub-urban community in South Eastern Nigeria

This study is aimed at assessing the impact of seizure frequency on the cognitive performance of epileptic adult patients in a rural community in South Eastern Nigeria. A total of 51 patients with epilepsy (33 males and 18 females) with a mean age of 30.7 ± 12.1 years and 51 age and sex matched controls participated in this study. The cognitive performances of the people with epilepsy and controls were assessed using the Community Screening Interview for Dementia (CSID) and the computerized cognitive assessment test battery, the FePsy. The control group performed better in almost all the neurocognitive tests compared with the low seizure frequency (LSF) and high seizure frequency (HSF) groups. Analysis of covariance revealed that patients with LSF performed better (p = 0.04) in visual reaction time - dominant hand (VRT-D) compared with the HSF group. There was lack of significant differences in mean total CSID scores and mean sub-total scores for language, memory, orientation, attention, constructional praxis, auditory reaction time-dominant hand and non-dominant hand, VRT - non-dominant hand and figure recognition. HSF patients indicated significantly greater prevalence (80% vs. 20%; p = 0.020) and risk (OR, 8.0; 95% CI, 1.8-33.8)) of memory impairment, but not in the other neurocognitive domains compared with the LSF group. In conclusion, the present study indicated that adults with epilepsy performed poorly in a wide range of neurocognitive variables compared with the controls. However, no significant adverse effects of high seizure frequency were observed on almost all the neurocognitive variables.

Cognition and dementia in older patients with epilepsy

With advances in healthcare and an ageing population, the number of older adults with epilepsy is set to rise substantially across the world. In developed countries the highest incidence of epilepsy is already in people over 65 and, as life expectancy increases, individuals who developed epilepsy at a young age are also living longer. Recent findings show that older persons with epilepsy are more likely to suffer from cognitive dysfunction and that there might be an important bidirectional relationship between epilepsy and dementia. Thus some people with epilepsy may be at a higher risk of developing dementia, while individuals with some forms of dementia, particularly Alzheimer's disease and vascular dementia, are at significantly higher risk of developing epilepsy. Consistent with this emerging view, epidemiological findings reveal that people with epilepsy and individuals with Alzheimer's disease share common risk factors. Recent studies in Alzheimer's disease and late-onset epilepsy also suggest common pathological links mediated by underlying vascular changes and/or tau pathology. Meanwhile electrophysiological and neuroimaging investigations in epilepsy, Alzheimer's disease, and vascular dementia have focused interest on network level dysfunction, which might be important in mediating cognitive dysfunction across all three of these conditions. In this review we consider whether seizures promote dementia, whether dementia causes seizures, or if common underlying pathophysiological mechanisms cause both. We examine the evidence that cognitive impairment is associated with epilepsy in older people (aged over 65) and the prognosis for patients with epilepsy developing dementia, with a specific emphasis on common mechanisms that might underlie the cognitive deficits observed in epilepsy and Alzheimer's disease. Our analyses suggest that there is considerable intersection between epilepsy, Alzheimer's disease and cerebrovascular disease raising the possibility that better understanding of shared mechanisms in these conditions might help to ameliorate not just seizures, but also epileptogenesis and cognitive dysfunction.

Effects of Epilepsy on Language Functions: Scoping Review and Data Mining Findings

PURPOSE

This study involved a scoping review to identify possible gaps in the empirical description of language functioning in epilepsy in adults. With access to social network data, data mining was used to determine if individuals with epilepsy are expressing language-related concerns.

METHOD

For the scoping review, scientific databases were explored to identify pertinent articles. Findings regarding the nature of epilepsy etiologies, patient characteristics, tested language modalities, and language measures were compiled. Data mining focused on social network databases to obtain a set of relevant language-related posts.

RESULTS

The search yielded 66 articles. Epilepsy etiologies except temporal lobe epilepsy and older adults were underrepresented. Most studies utilized aphasia tests and primarily assessed single-word productions; few studies included healthy control groups. Data mining revealed several posts regarding epilepsy-related language problems, including word retrieval, reading, writing, verbal memory difficulties, and negative effects of epilepsy treatment on language.

CONCLUSION

Our findings underscore the need for future specification of the integrity of language in epilepsy, particularly with respect to discourse and high-level language abilities. Increased awareness of epilepsy-related language issues and understanding the patients' perspectives about their language concerns will allow researchers and speech-language pathologists to utilize appropriate assessments and improve quality of care.

Cognitive dysfunction in naturally occurring canine idiopathic epilepsy

Globally, epilepsy is a common serious brain disorder. In addition to seizure activity, epilepsy is associated with cognitive impairments including static cognitive impairments present at onset, progressive seizure-induced impairments and co-morbid dementia. Epilepsy occurs naturally in domestic dogs but its impact on canine cognition has yet to be studied, despite canine cognitive dysfunction (CCD) recognised as a spontaneous model of dementia. Here we use data from a psychometrically validated tool, the canine cognitive dysfunction rating (CCDR) scale, to compare cognitive dysfunction in dogs diagnosed with idiopathic epilepsy (IE) with controls while accounting for age. An online cross-sectional study resulted in a sample of 4051 dogs, of which n = 286 had been diagnosed with IE. Four factors were significantly associated with a diagnosis of CCD (above the diagnostic cut-off of CCDR ≥50): (i) epilepsy diagnosis: dogs with epilepsy were at higher risk; (ii) age: older dogs were at higher risk; (iii) weight: lighter dogs (kg) were at higher risk; (iv) training history: dogs with more exposure to training activities were at lower risk. Impairments in memory were most common in dogs with IE, but progression of impairments was not observed compared to controls. A significant interaction between epilepsy and age was identified, with IE dogs exhibiting a higher risk of CCD at a young age, while control dogs followed the expected pattern of low-risk throughout middle age, with risk increasing exponentially in geriatric years. Within the IE sub-population, dogs with a history of cluster seizures and high seizure frequency had higher CCDR scores. The age of onset, nature and progression of cognitive impairment in the current IE dogs appear divergent from those classically seen in CCD. Longitudinal monitoring of cognitive function from seizure onset is required to further characterise these impairments.

Causal inference as an emerging statistical approach in neurology: an example for epilepsy in the elderly

The elderly population faces an increasing number of cases of chronic neurological conditions, such as epilepsy and Alzheimer's disease. Because the elderly with epilepsy are commonly excluded from randomized controlled clinical trials, there are few rigorous studies to guide clinical practice. When the elderly are eligible for trials, they either rarely participate or frequently have poor adherence to therapy, thus limiting both generalizability and validity. In contrast, large observational data sets are increasingly available, but are susceptible to bias when using common analytic approaches. Recent developments in causal inference-analytic approaches also introduce the possibility of emulating randomized controlled trials to yield valid estimates. We provide a practical example of the application of the principles of causal inference to a large observational data set of patients with epilepsy. This review also provides a framework for comparative-effectiveness research in chronic neurological conditions.

Anterior temporal lobectomy for older adults with mesial temporal sclerosis

OBJECTIVE

To compare postoperative seizure-free survival between older and younger adults.

METHODS

A retrospective cohort of 107 temporal lobe epilepsy patients with a diagnosis of mesial temporal sclerosis (MTS) received anterior temporal lobectomy (ATL) between 1993 and 2014. We divided the lower three quartiles (younger) and top quartile (older, all 47+ years) of patients, then reviewed patient registry and electronic medical records to determine time to first self-reported seizure after ATL, the primary outcome (mean=3.5years of follow-up, SD=3.6). We also assessed Engel classifications, intraoperative and postoperative treatment complications, and social disability. We used Cox proportional hazard models to assess the association between individual traits and time of seizure recurrence.

RESULTS

During follow-up, 35/107 (32.7%) patients had post-operative seizure(s). After adjustment for potential confounders there were no significant differences in the probability of post-operative seizures between the older and younger groups, though we had limited precision (hazard ratio of 0.67 [0.28-1.59]), (p=0.36). There were more treatment complications and disability in older patients (18% vs. 1.3% for any complications, 84.62% vs. 58.23% for driving disability, and 84.6% vs. 60.7% for work disability, p<0.05).

CONCLUSION

Older patients appear to have more complications after ATL, compared with younger patients. Age, however, does not appear to have a large independent association with seizure recurrence.

Hyperphosphorylated tau in patients with refractory epilepsy correlates with cognitive decline: a study of temporal lobe resections

SEE BERNASCONI DOI101093/AWW202 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Temporal lobe epilepsy, the most prevalent form of chronic focal epilepsy, is associated with a high prevalence of cognitive impairment but the responsible underlying pathological mechanisms are unknown. Tau, the microtubule-associated protein, is a hallmark of several neurodegenerative diseases including Alzheimer's disease and chronic traumatic encephalopathy. We hypothesized that hyperphosphorylated tau pathology is associated with cognitive decline in temporal lobe epilepsy and explored this through clinico-pathological study. We first performed pathological examination on tissue from 33 patients who had undergone temporal lobe resection between ages 50 and 65 years to treat drug-refractory temporal lobe epilepsy. We identified hyperphosphorylated tau protein using AT8 immunohistochemistry and compared this distribution to Braak patterns of Alzheimer's disease and patterns of chronic traumatic encephalopathy. We quantified tau pathology using a modified tau score created specifically for analysis of temporal lobectomy tissue and the Braak staging, which was limited without extra-temporal brain areas available. Next, we correlated tau pathology with pre- and postoperative cognitive test scores and clinical risk factors including age at time of surgery, duration of epilepsy, history of secondary generalized seizures, history of head injury, handedness and side of surgery. Thirty-one of 33 cases (94%) showed hyperphosphorylated tau pathology in the form of neuropil threads and neurofibrillary tangles and pre-tangles. Braak stage analysis showed 12% of our epilepsy cohort had a Braak staging III-IV compared to an age-matched non-epilepsy control group from the literature (8%). We identified a mixture of tau pathology patterns characteristic of Alzheimer's disease and chronic traumatic encephalopathy. We also found unusual patterns of subpial tau deposition, sparing of the hippocampus and co-localization with mossy fibre sprouting, a feature of temporal lobe epilepsy. We demonstrated that the more extensive the tau pathology, the greater the decline in verbal learning (Spearman correlation, r = -0.63), recall (r = -0.44) and graded naming test scores (r = -0.50) over 1-year post-temporal lobe resection (P < 0.05). This relationship with tau burden was also present when examining decline in verbal learning from 3 months to 1 year post-resection (r = -0.54). We found an association between modified tau score and history of secondary generalized seizures (likelihood-ratio χ(2), P < 0.05) however there was no clear relationship between tau pathology and other clinical risk factors assessed. Our findings suggest an epilepsy-related tauopathy in temporal lobe epilepsy, which contributes to accelerated cognitive decline and has diagnostic and treatment implications.

A community-based case-control study of prevalence and pattern of cognitive impairments in patients with epilepsy residing in South-Eastern Nigeria

BACKGROUND

Epilepsy is the commonest neurological disorder encountered in Sub-Saharan Africa. The quality of life of patients with epilepsy (PWEs) is adversely affected by cognitive impairments.

AIM

This study investigated the prevalence and pattern of cognitive impairments in PWE in Ukpo community located in a South-Eastern state in Nigeria using Community Screening Interview for Dementia (CSID) and a computer-assisted cognitive test battery (FePsy).

METHODS AND PATIENTS

Fifty-one PWEs were studied and compared with 51 age-, sex-and level of education-matched healthy controls. Diagnosis of epilepsy was confirmed clinically with eye-witness corroboration. Sociodemographic data and information on epilepsy variables were obtained with the aid of a questionnaire. Cognitive domains assessed include language, memory, orientation, attention, psychomotor speed and constructional praxis.

RESULTS

The prevalence rate of cognitive impairment using total CSID score was 19.6%. Analysis of CSID scores revealed significant impairment in language (17.6%), memory (29.4%), orientation (15.7%), attention (7.8%) and constructional praxis (15.7%) compared to healthy controls. A similar pattern was observed with FePsy but with better sensitivity indices for detecting cognitive impairment.

CONCLUSION

This study indicated significant prevalence rate of cognitive impairment among treatment-naïve PWE with profound affectation of memory, mental speed and language. In addition, the FePsy was found to be more sensitive and specific in assessment of cognitive function in PWE.

Cognitive impairment in older adults with epilepsy: Characterization and risk factor analysis

OBJECTIVE

Cognitive deficits are common in epilepsy, though the impact of epilepsy on cognition in older adults is understudied. This study aimed to characterize cognition in older adults with epilepsy compared with healthy older adults and identify potential risk factors for impairment.

METHODS

Thirty-eight older adults with epilepsy and 29 healthy controls completed a comprehensive neuropsychological battery, as well as measures of depression and anxiety. Chart review for current medications, seizure history, and neuroimaging was also completed. To compare cognitive performance between groups, ANOVA was used, and linear regression identified predictors of impairment among the group with epilepsy.

RESULTS

Patients with epilepsy performed worse across nearly all cognitive domains, and were clinically impaired (i.e., ≥ 1.5 SD below mean) on more individual tests when compared with controls, including a subset of patients with epilepsy with normal MRIs. For all patients with epilepsy, taking a greater number of antiepileptic drugs was associated with poorer language and visuospatial abilities, and higher anxiety was associated with poorer visual memory.

CONCLUSIONS

Older adults with epilepsy demonstrated greater cognitive deficits than matched controls. Polytherapy and anxiety heightened the risk for cognitive impairment in some cognitive domains, but not in others. Understanding the nature of cognitive decline in this population, as well as associated risk factors, may assist in the differential diagnosis of cognitive complaints and improve the design of treatment studies for older patients with epilepsy. Replication in larger, longitudinal studies is warranted to generalize these findings.

Subjective cognitive complaints versus objective neuropsychological performance in older adults with epilepsy

Memory complaints are common among older adults with epilepsy (OAE), though discrepancy between subjective complaints and objective performance often exists. This study examined how accurately OAE and their informants reported on the participant's cognitive difficulties by comparing ratings of everyday cognition to objective performance. Thirty-seven OAE and 27 older adult controls completed a brief battery of neuropsychological tests, the Beck Depression Inventory, and the Cognitive Difficulties Scale (CDS). Each participant had an informant who completed the CDS. Older adults with epilepsy performed worse than controls on cognitive testing and reported more subjective cognitive complaints. Neither participant- nor informant-reported cognitive complaints were related to performance on any of the neuropsychological tests for either the group with epilepsy or control group, but both were related to greater depressive symptoms. Results suggest that subjective report of cognitive problems by both OAE and their informants may not reliably reflect the extent to which these problems exist.

Cognitive outcomes of temporal lobe epilepsy surgery in older patients

PURPOSE

To examine the cognitive risks of temporal lobe surgery in patients aged 50 years and older.

METHODS

We analysed data from 55 patients who underwent temporal lobe surgery (26 left-sided:29 right sided) from 1988 to 2012 at our centre. Pre-surgical and one year post-operative memory and naming capacity were compared to data obtained from two younger cohorts; 185 aged 18-30 and 220 aged 31-49.

RESULTS

Pre-operative memory impairments were most marked for the oldest cohort and were associated with a longer duration of epilepsy. Naming capacity improved with age and better performance was associated with a later age at epilepsy onset. Post-operative declines were largest in older patients, achieving statistical significance for verbal memory, naming and subjective ratings. Left temporal lobe resections carried the greatest risk of memory and naming decline. Cognitive outcomes were unrelated to seizure outcome, VIQ or mood.

CONCLUSION

Our findings indicate the cognitive risks of TLE surgery are greater for older patients. Cognitive outcomes need to be considered when assessing the efficacy of epilepsy surgery in older cohorts and pre-operative performance levels need to be taken into account.

Risk factors for dementia in a senegalese elderly population aged 65 years and over

Background

With the aging of the population, dementia is increasing worldwide. The objective of this study was to identify risk factors for dementia in an elderly population utilizing a primary health care service in Dakar, Senegal.

Methods

Through a cross-sectional study conducted from March 2004 to December 31, 2005, 507 elderly patients aged ≥65 years who came to the Social and Medical Center of IPRES, Dakar, Senegal, were first screened with the screening interview questionnaire ‘Aging in Senegal’. Those who were cognitively impaired underwent a clinical examination to detect dementia. Univariate, bivariate, and multivariate logistic regression analyses were done.

Results

The whole population had a mean age of 72.4 years (±5.2) and was mostly male, married, and non-educated. Hypertension, arthritis, and gastrointestinal diseases were the main health conditions reported in the past medical history. Smoking was important while alcohol consumption was rare. Social network was high. Forty-five patients (8.87%) had dementia. In the multivariate model, only advanced age, education, epilepsy, and family history of dementia were independently associated with dementia.

Conclusion

The risk factors identified are also found in developed countries confirming their role in dementia. It is important to take dementia into consideration in Senegal and to sensitize the community for prevention.

Geriatric epilepsy: research and clinical directions for the future

There is a growing awareness of the need for improved treatment and care of older adults with epilepsy. The present review article highlights key clinical and research issues in the emerging field of geriatric epilepsy. Drs. Martin and Schmidt explore the scope of the problems in the field, outline topic areas including cognitive health/dementia, and diagnostic challenges, and also present important research questions that should be considered for the future. As part of this presentation, we will highlight the work of two promising young investigators whose work holds great promise for the field of geriatric epilepsy. Dr. Roberson will discuss his work focusing on the relationship of epilepsy and cognitive impairment, particularly as it relates to Alzheimer's disease pathology including tau and its role in epileptiform activity. Dr. Hope will outline key issues, as well as her work, relating to defining and measuring quality care in geriatric epilepsy.

Review of topiramate for the treatment of epilepsy in elderly patients

Individuals over 65 years of age experience the new onset of seizures at a prevalence rate of roughly twice that of younger adults. Differences in physiology, need of concomitant medications, and liability for cognitive deficits in this population, make the choice of anticonvulsant drugs especially important. This paper reviews topiramate (TPM), a treatment for many types of seizures, with the above risks in mind. In particular, we discuss efficacy and pharmacokinetics with emphasis on the older patient, and adverse events in both the younger and older adult. With most studies of TPM-induced cognitive deficits having been performed in younger adults and volunteers, we discuss the implications for the older adult. Even in studies of younger individuals, up to 50% discontinue TPM because of intolerable cognitive deficits. Most studies find specific declines in working memory and verbal fluency. In conclusion, we give recommendations for use of this antiepileptic drug in this population.

Epileptic seizures in AD patients

Epileptic seizures have long been recognised as a complication of the clinical syndrome of Alzheimer's disease, particularly in advanced disease, but have hitherto been viewed essentially as epiphenomena of the neurodegenerative process. Progress with animal models of Alzheimer's disease has suggested that this view may be incorrect, and that seizures may be a reflection of pathophysiological processes similar to or overlapping with those responsible for cognitive decline. This overlap between neuropsychological and neurophysiological changes suggests that seizures in Alzheimer's disease may be a valid therapeutic target, over and above symptomatic treatment. This article reviews data on the prevalence of seizures in Alzheimer's disease, seizure types, pathophysiology and treatment. Seizure prevalence increases with disease duration, but early-onset disease is associated with a greater risk of seizures, in part related to the frequency of presenilin-1 gene mutations in early-onset disease. Seizures are mostly of partial origin, with both complex partial and secondary generalised seizures. Seizure pathophysiology may relate to increased amyloid beta-peptide production, structural alterations in neurones related to cytoskeletal dysfunction, cerebrovascular changes, neurotransmitter dysfunction or combinations thereof. Through modification of these pathophysiological pathways, there may be possible roles for anti-epileptic drugs such as sodium valproate and lacosamide in the treatment of Alzheimer's disease. In summary, epileptic seizures are part of the AD phenotype, and merit further investigation.

Cognitive assessment in patients with epilepsy using the Community Screening Interview for Dementia

OBJECTIVE

Epilepsy is the most common neurological disease worldwide. It may be complicated by cognitive impairments with consequent deleterious effects on education, vocation, and social and family life of affected individuals. We assessed the cognitive functions of Nigerian patients with epilepsy using the modified Community Screening Interview for Dementia (CSID) questionnaire.

METHODS

Eighty-two subjects (41 patients with epilepsy and 41 normal controls) participated in the study. The CSID was used to assess language, memory, orientation, attention, calculation, and praxis. The SPSS statistical package was used for data analysis.

RESULTS

The mean ages (in years) of patients with epilepsy and controls were 28.32+/-9.22 and 25.98+/-7.72, respectively. The patients with epilepsy performed poorly when compared with the controls (P<0.05) in the domains Language, Memory, Attention and Calculation, and Praxis, whereas there was no statistically significant difference between the patients and controls in Orientation scores. Duration of epilepsy and of antiepileptic drug (AED) therapy had a significant negative impact on all domains of the CSID (P<0.05), whereas type of AED used did not. The CSID had a sensitivity of 91.7%.

CONCLUSION

This study showed that patients with epilepsy have significant cognitive impairments compared with controls, and duration of epilepsy and AED therapy have deleterious effects on their cognitive performance. In addition, the CSID has acceptable sensitivity and predictive value. It is recommended that cognitive function assessment should be an integral part of routine evaluation of patients with epilepsy.

Seizures in the elderly: impact on mental status, mood, and sleep

Comorbidities of epilepsy have not been well explored in the elderly. Herein, we examined mental status, mood, and sleep in elderly patients with epilepsy, compared with age- and gender-matched community controls without epilepsy from the Einstein Aging Study. Testing included a mental status test, the Blessed Information Memory and Concentration (BIMC) test; Prime-MD Patient Health Questionnaire (PHQ) Depression and Anxiety Modules; and Medical Outcomes Study Sleep Scale. Persons with epilepsy (n=31) had higher mean BIMC scores than controls (n=31, BIMC 6.3 vs.1.2, P<0.0001). Mean PHQ Depression scores were higher for cases than controls, indicating more depressive symptoms (4.2 vs 0.8, P=0.006); six cases (18%) and no controls met screening criteria for depression. Mean PHQ Anxiety scores were also higher for cases than controls (3.7 vs 0.0, P=0.001). Cases had poorer sleep scores in the categories of somnolence (P=0.009) and shortness of breath/headache (P=0.021). Thus, comorbidities of epilepsy in this elderly population included decreased mental status, a higher prevalence of depression and anxiety, and poorer sleep health when compared with agemates without epilepsy. Mental status impairment was not related to antiepileptic medication or mood disturbance. Further investigation will explore these associations prospectively.