Predictors of incident epilepsy in older adults: The Cardiovascular Health Study

Serum Klotho levels and epilepsy among U.S. adults in the NHANES 2013-2016: a cross-sectional study

The relationship between Klotho and epilepsy is poorly understood. This study aimed to investigate the association between serum Klotho levels and epilepsy. A total of 99,966 individuals who participated in the NHANES from the 2013 to 2016 were initially included. After excluding participants with missing data on serum Klotho concentration (57,286), epilepsy (6) and relevant covariates (6,096), the final sample consisted of 36,578 participants, with a mean age of 59 years. Weighted multivariable logistic regression analyses showed that high serum Klotho levels were negatively associated with the prevalence of epilepsy, with an odds ratio (OR) of 0.74 (95% confidence interval [CI]: 0.64 to 0.86; P < 0.001. The Restricted Cubic Spline analyses (RCS) model showed a non-linear relationship between the serum Klotho levels and epilepsy. Subgroup analysis showed that serum Klotho levels were negatively correlated with epilepsy prevalence in individuals under 65 years of age and in males. Our study suggests that serum Klotho levels were associated with the prevalence of epilepsy. Further large-scale prospective studies and randomized trials are warranted to confirm our findings.

Management and outcomes among older adults with generalized epilepsy in routine clinical practice

Generalized epilepsy is classically thought of as a disease of the young and adolescent, with rarely reported cases among older adults. We aimed to analyze management and outcomes in a population sparsely described in the literature through a retrospective single-center cohort design. After excluding individuals without follow-up, we identified 151 people ≥50 years at the time of electrographically confirmed generalized epilepsy. Just over a quarter were late-onset (≥26 years), and 77% were diagnosed with genetic generalized epilepsy (GGE). Active seizures (in the last year of follow-up) were present in 57% of individuals, despite most of them having experienced prolonged seizure remission periods (median 7 years) in the past. Only five people were off antiseizure medication (ASM) at their last appointment, with most on an average of 2 ASMs. The odds of active epilepsy at the last follow-up were significantly higher among those with polyspikes (odds ratio [OR] = 2.42; 95% confidence interval [CI] = 1.01-6.01), myoclonic seizure history (OR = 2.88, 1.23-6.96), and developmental delay (OR = 4.75, 1.45-19.3). The odds were 60% lower in older adults with family history (OR = 0.4, 0.17-5.68). Our findings suggest that most older adults with generalized epilepsy achieve years of seizure remission, but the likelihood of epilepsy resolution is low. PLAIN LANGUAGE SUMMARY: Generalized epilepsy is seldom seen in older adults. We looked at 151 patients diagnosed with generalized epilepsy over the age of 50 to see how they are managed and what influences their outcomes. We found that although these patients can control their seizures with medication, the chance that their epilepsy resolves is low. Patients with certain characteristics classically seen in an epilepsy called "Juvenile Myoclonic Epilepsy" (JME) may have a more intractable course.

Late-onset first epileptic seizure and cerebral small vessel disease: role of juxtacortical white matter lesions

Objective

The cause of late-onset first epileptic seizures (LOFES) in older age is often not readily evident. In absence of probable causes, it has been suggested that cerebral small vessel disease (CSVD), which is common with increasing age, may be crucial. We aimed to further investigate the impact of white matter lesion (WML) burden and distribution pattern on LOFES.

Methods

We retrospectively compared structural MRI of LOFES patients (n = 39) aged 60 years or older to controls with a transient ischemic attack (TIA, n = 38) and to patient controls (n = 35). WML segmentation was performed on FLAIR images using the SPM based automated lesion prediction algorithm of the LST toolbox and careful manual adjustment. Further, a dichotomization of WML was achieved by use of the BIANCA masking function. A voxel-based morphometry (VBM) analysis was additionally performed on T1 weighted sequences using the automated SPM12 based CAT12 software.

Results

Comparing intrapersonal volume ratios adjusted for the effects of gender and age, we found that the WML distribution was shifted to the juxtacortical compartment in LOFES patients. Among several influencing variables a path analysis could additionally show that this juxtacortical weighting of WML was a significant predictor for LOFES (β = 0.509, p < 0.001). With regard to total WML volume, LOFES and TIA patients did not differ significantly. Compared to TIA group, LOFES patients gray matter volume was regionally decreased in the right pre- and postcentral gyrus.

Significance

By using algorithm-based automated lesion segmentation software tools and VBM analysis we could highlight that a juxtacortical weighting of WML distribution and regionally decreased gray matter volume distinguished LOFES from TIA and PC groups in our sample.

Racial/ethnic differences in the association of incident stroke with late onset epilepsy: The Northern Manhattan Study

OBJECTIVE

Little is known about the incidence of late onset epilepsy (LOE) across different racial/ethnic groups in the USA, particularly in the Hispanic population. Stroke, a strong predictor of LOE, is more common in non-Hispanic Blacks (NHBs) and Hispanics than in non-Hispanic Whites (NHWs). We assessed the incidence of LOE across racial/ethnic groups and examined whether the associations of stroke with LOE risk differ by race/ethnicity.

METHODS

The Northern Manhattan Study is a population-based longitudinal study of older adults enrolled between 1993 and 2001. Participants free of history of stroke or epilepsy at baseline (n = 3419) were followed prospectively for incidence of LOE. We estimated LOE incidence per 1000 person-years in each racial/ethnic group. We used Cox proportional hazards regression to assess the association of race/ethnicity with LOE and multiplicative interactions of race/ethnicity with incident stroke in relation to LOE, adjusting for demographics and comorbid diagnoses.

RESULTS

During 51 176 person-years of follow-up, 183 individuals developed LOE. Incidence of LOE was significantly higher in NHBs (6.2 per 1000 person-years) than in NHWs (3.3 per 1000 person-years, p = .004). There was no significant difference in LOE incidence between NHWs (3.3 per 1000 person-years) and Hispanics (2.6 per 1000 person-years, p = .875). However, following incident stroke, the risk of LOE differed across racial/ethnic groups. Incident stroke was associated with 2.55 times the risk of LOE among NHWs (95% confidence interval [CI] = .88-7.35), 8.53 times the risk of LOE among Hispanics (95% CI = 5.36-13.57, p = .04 for stronger association than that in NHWs), and 6.46 times the risk of LOE among NHBs (95% CI = 3.79-11.01, p = .12 for stronger association than that in NHWs).

SIGNIFICANCE

We found a stronger association of incident stroke with LOE risk in Hispanics and NHBs than in NHWs, offering some insight into the racial/ethnic disparities of LOE incidence.

Incident Epilepsy Among US Medicare Beneficiaries, 2019: Differences by Age, Sex, and Race/Ethnicity

BACKGROUND AND OBJECTIVES

Epilepsy is common among older adults, but previous incident studies have had limited ability to make comparisons across key subgroups. We aimed to provide updated epilepsy incidence estimates among older adults, comparing across age, sex, and race/ethnicity.

METHODS

Using a random sample of 4,999,999 US Medicare beneficiaries older than 65 years, we conducted a retrospective cohort study of epilepsy incidence using administrative claims for 2016-2019. Sampled beneficiaries were enrolled in the Fee-for-Service (FFS) program in each of 2016-2018 and had no epilepsy claims in those years. Non-Hispanic Black and Hispanic beneficiaries were oversampled to ensure adequate cases for detailed comparisons. Incidence in 2019 was identified in the Master Beneficiary Summary File as ≥1 inpatient claim or ≥2 outpatient nondrug claims occurring at least 1 day apart (ICD-10 G40.x). Incidence models were estimated by age, sex, race/ethnicity, and combinations thereof, with adjustment for the racial/ethnic oversampling.

RESULTS

We identified 20,545 incident epilepsy cases. The overall epilepsy incidence rate (IR) was 393 per 100,000 (99% CI 385-400). Incidence peaked at ages 85-89 (504 [481-529]) and was higher for men (396 [385-407]) than women (376 [366-385]). The sex difference in IRs was constant with age. Incidence was higher for non-Hispanic Black (678 [653-702]) and Hispanic (405 [384-426]), and lower for non-Hispanic Asian/Pacific Islander (272 [239-305]) beneficiaries, compared with non-Hispanic White beneficiaries (354 [299-408]). The age-specific IRs significantly differed by race/ethnicity and sex, but only among non-Hispanic Black beneficiaries-where men had higher rates at younger ages and women at older ages.

DISCUSSION

We found higher epilepsy IRs among those enrolled in the Medicare FFS system 2016-2019 than previous studies using Medicare claims data from at least a decade ago. The risk of epilepsy onset is higher for those in their late 80s, men, and non-Hispanic Black and Hispanic older adults. There is also evidence that these age-graded risks operate differently for Black men and Black women. Efforts to provide care and services that improve quality of life for older adults living with epilepsy should consider differences by multiple social characteristics simultaneously: age, sex, and race/ethnicity.

Clinical and paraclinical features of first unprovoked seizures in the elderly

PURPOSE

The prevalence of unprovoked seizures and epilepsy rises significantly in later life stages. This study examines various factors in elderly patients (over 65 years) with their first unprovoked seizures, comparing findings with younger patients.

METHODS

We analyzed electronic medical records of individuals with first unprovoked seizures retrospectively. Diagnosis was based on patient history and witness accounts, and exclusion of other potential causes. Data included demographics, physical examination, seizure characteristics, neuroimaging, EEG findings, laboratory markers, potential causes, prescribed anti-seizure medications (ASMs) at diagnosis and follow-up, seizure-related injuries and hospital stay length.

RESULTS

We enrolled 391 patients (mean age 73.02 ± 16.5, 219 females). Most had late-onset (≥65 years) seizures (n = 295, 75.5 %). Status epilepticus was diagnosed in 10.2 %, more in the late-onset group. Elderly patients most often had focal seizures with impaired consciousness, while younger patients had focal to bilateral tonic-clonic seizures. (55.9 % vs 36.5 %). Late-onset seizures were linked to cerebrovascular diseases, small vessel disease, and cerebral atrophy, while early-onset cases were associated with brain tumors or unknown causes. Brain imaging revealed potentially epileptogenic abnormalities in 59.1 %. Positive paraneoplastic or autoimmune antibodies were found in 0.8 %. Abnormal EEGs were present in 25.9 %, more in the late-onset group. Most patients were discharged with levetiracetam (LEV) or lamotrigine (LTG) monotherapy. Nine patients with late-onset seizures died during in-hospital follow-up.

CONCLUSION

Our findings can contribute to the improved identification and characterization of patients with late-onset seizures, facilitating targeted diagnostics and appropriate treatment in this challenging patient population.

Excess prevalence of preexisting chronic conditions in older adults with incident epilepsy

OBJECTIVE

Prior studies have examined chronic conditions in older adults with prevalent epilepsy, but rarely among those with incident epilepsy. Identifying the chronic conditions with which older adults present at epilepsy incidence assists with the evaluation of disease burden in this patient population and informs coordinated care development. The aim of this study was to identify preexisting chronic conditions with excess prevalence in older adults with incident epilepsy compared to those without.

METHODS

Using a random sample of 4 999 999 fee-for-service Medicare beneficiaries aged >65 years, we conducted a retrospective cohort study of epilepsy incidence in 2019. Non-Hispanic Black and Hispanic beneficiaries were oversampled. We identified preexisting chronic conditions from the 2016-2018 Medicare Beneficiary Summary Files and compared chronic condition prevalence between Medicare beneficiaries with and without incident epilepsy in 2019. We characterized variations in preexisting excess chronic condition prevalence by age, sex, and race/ethnicity, adjusting for the racial/ethnic oversampling.

RESULTS

We observed excess prevalence of most preexisting chronic conditions in beneficiaries with incident epilepsy (n = 20 545, weighted n = 19 631). For stroke, for example, the adjusted prevalence rate ratio (APRR) was 4.82 (99% CI:4.60, 5.04), meaning that, compared to those without epilepsy, beneficiaries with incident epilepsy in 2019 had 4.82 times the stroke prevalence. Similarly, beneficiaries with incident epilepsy had a higher prevalence rate for preexisting neurological conditions (APRR = 3.17, 99% CI = 3.08-3.27), substance use disorders (APRR = 3.00, 99% CI = 2.81-3.19), and psychiatric disorders (APRR = 1.98, 99% CI = 1.94-2.01). For most documented chronic conditions, excess prevalence among beneficiaries with incident epilepsy in 2019 was larger for younger age groups compared to older age groups, and for Hispanic beneficiaries compared to both non-Hispanic White and non-Hispanic Black beneficiaries.

SIGNIFICANCE

Compared to epilepsy-free Medicare beneficiaries, those with incident epilepsy in 2019 had a higher prevalence of most preexisting chronic conditions. Our findings highlight the importance of health promotion and prevention, multidisciplinary care, and elucidating shared pathophysiology to identify opportunities for prevention.

Health care disparities in morbidity and mortality in adults with acute and remote status epilepticus: A national study

OBJECTIVE

Although disparities have been described in epilepsy care, their contribution to status epilepticus (SE) and associated outcomes remains understudied.

METHODS

We used the 2010-2019 National Inpatient Sample to identify SE hospitalizations using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)/ICD-10-CM codes. SE prevalence was stratified by demographics. Logistic regression was used to assess factors associated with electroencephalographic (EEG) monitoring, intubation, tracheostomy, gastrostomy, and mortality.

RESULTS

There were 486 861 SE hospitalizations (2010-2019), primarily at urban teaching hospitals (71.3%). SE prevalence per 10 000 admissions was 27.3 for non-Hispanic (NH)-Blacks, 16.1 for NH-Others, 15.8 for Hispanics, and 13.7 for NH-Whites (p < .01). SE prevalence was higher in the lowest (18.7) compared to highest income quartile (18.7 vs. 14, p < .01). Older age was associated with intubation, tracheostomy, gastrostomy, and in-hospital mortality. Those ≥80 years old had the highest odds of intubation (odds ratio [OR] = 1.5, 95% confidence interval [CI] = 1.43-1.58), tracheostomy (OR = 2, 95% CI = 1.75-2.27), gastrostomy (OR = 3.37, 95% CI = 2.97-3.83), and in-hospital mortality (OR = 6.51, 95% CI = 5.95-7.13). Minority populations (NH-Black, NH-Other, and Hispanic) had higher odds of tracheostomy and gastrostomy compared to NH-White populations. NH-Black people had the highest odds of tracheostomy (OR = 1.7, 95% CI = 1.57-1.86) and gastrostomy (OR = 1.78, 95% CI = 1.65-1.92). The odds of receiving EEG monitoring rose progressively with higher income quartile (OR = 1.47, 95% CI = 1.34-1.62 for the highest income quartile) and was higher for those in urban teaching compared to rural hospitals (OR = 12.72, 95% CI = 8.92-18.14). Odds of mortality were lower (compared to NH-Whites) in NH-Blacks (OR = .71, 95% CI = .67-.75), Hispanics (OR = .82, 95% CI = .76-.89), and those in the highest income quartiles (OR = .9, 95% CI = .84-.97).

SIGNIFICANCE

Disparities exist in SE prevalence, tracheostomy, and gastrostomy utilization across age, race/ethnicity, and income. Older age and lower income are also associated with mortality. Access to EEG monitoring is modulated by income and urban teaching hospital status. Older adults, racial/ethnic minorities, and populations of lower income or rural location may represent vulnerable populations meriting increased attention to improve health outcomes and reduce disparities.

Association of Age-Related Neuropathologic Findings at Autopsy With a Claims-Based Epilepsy Diagnosis in Older Adults

BACKGROUND AND OBJECTIVES

Epilepsy is 1 of the 3 most common neurologic diseases of older adults, but few studies have examined its underlying pathologies in older age. We examined the associations of age-related brain pathologies with epilepsy in older persons.

METHODS

Clinical and pathologic data came from 2 ongoing clinical pathologic cohort studies of community-dwelling older adults. Epilepsy was ascertained using Medicare fee-for-service Parts A and B claims data that were linked to data from the cohort studies. The postmortem pathologic assessment collected indices of 9 pathologies including Alzheimer disease, hippocampal sclerosis, macroinfarcts, and cerebral amyloid angiopathy. The fixed brain hemisphere was imaged using 3T MRI scanners before the pathologic assessments in a subgroup of participants.

RESULTS

The participants (n = 1,369) were on average 89.3 (6.6) years at death, and 67.0% were women. Epilepsy was identified in 58 (4.2%) participants. Cerebral amyloid angiopathy (odds ratio [OR] = 2.21, 95% CI 1.24-3.95, p = 0.007) and cortical macroinfarcts (OR = 2.74, 95% CI 1.42-5.28, p = 0.003) were associated with a higher odds of epilepsy. Of note, hippocampal sclerosis and Alzheimer disease pathology were not associated with epilepsy (both p's > 0.25), although hippocampal sclerosis was not common and thus hard to examine with the modest number of epilepsy cases here. In 673 participants with MRI data, the association of cerebral amyloid angiopathy and cortical macroinfarcts with epilepsy did not change after controlling for cortical gray matter atrophy, which was independently associated with a higher odds of epilepsy (OR = 1.06, 95% CI 1.02-1.10, p = 0.003). By contrast, hippocampal volume was not associated with epilepsy.

DISCUSSION

Cerebrovascular pathologies and cortical atrophy were associated with epilepsy in older persons.

Latest advances in mechanisms of epileptic activity in Alzheimer's disease and dementia with Lewy Bodies

Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) stand as the prevailing sources of neurodegenerative dementia, impacting over 55 million individuals across the globe. Patients with AD and DLB exhibit a higher prevalence of epileptic activity compared to those with other forms of dementia. Seizures can accompany AD and DLB in early stages, and the associated epileptic activity can contribute to cognitive symptoms and exacerbate cognitive decline. Aberrant neuronal activity in AD and DLB may be caused by several mechanisms that are not yet understood. Hyperexcitability could be a biomarker for early detection of AD or DLB before the onset of dementia. In this review, we compare and contrast mechanisms of network hyperexcitability in AD and DLB. We examine the contributions of genetic risk factors, Ca2+ dysregulation, glutamate, AMPA and NMDA receptors, mTOR, pathological amyloid beta, tau and α-synuclein, altered microglial and astrocytic activity, and impaired inhibitory interneuron function. By gaining a deeper understanding of the molecular mechanisms that cause neuronal hyperexcitability, we might uncover therapeutic approaches to effectively ease symptoms and slow down the advancement of AD and DLB.

Leukotriene antagonists reduce epileptic seizures-related hospitalization in older adult populations with allergic rhinitis or asthma: A population-based cohort study using the Shizuoka Kokuho database: The Shizuoka study

OBJECTIVE

Managing the risk of epileptic seizures in older adults is increasingly important as the population ages. Leukotriene receptor antagonists (LTRAs) are commonly used to treat asthma or allergic rhinitis. Preclinical studies suggest that LTRAs have antiepileptic effects; however, few population-based etiological studies on this topic have been available. Our study explored whether LTRAs reduce hospitalization risk associated with epileptic seizures in older individuals with asthma or allergic rhinitis.

METHODS

We conducted a new-user design analysis using the Shizuoka Kokuho database. We included all individuals aged 60-89 years who had at least one episode of allergic rhinitis or asthma during the study period. We compared individuals who newly started LTRAs with those who did not take LTRAs. Propensity score matching was used to balance the baseline characteristics of the participants. We compared the hazard ratios for seizure-related hospitalization between new LTRA users and non-users and performed subgroup analyses.

RESULTS

Our matched cohorts consisted of 64 724 new users and non-users of LTRAs who were aged 60-89 years and had asthma or allergic rhinitis. During the observation period, 377 (0.58%) and 595 (0.92%) incidents were observed in the LTRA new-user and non-user groups, respectively. The hazard ratio for seizure-related hospitalization was 0.75 (95% confidence interval [CI]: 0.62-0.92) in the LTRA new-user group compared with the non-user group. Subgroup analysis revealed that the hazard ratio was weak in diabetic patients (1.31; 95% CI: 0.72-2.38).

SIGNIFICANCE

This study indicated that LTRAs reduced seizure-related hospitalization in older adult patients with allergic rhinitis or asthma. We could not evaluate the severity and related diseases of epileptic seizures during LTRAs. Further studies, including observational studies, detailed multicenter prospective studies, and clinical trials, are needed to validate these findings.

PLAIN LANGUAGE SUMMARY

This study examined if leukotriene receptor antagonists (LTRAs), commonly used for asthma or allergies, could lower seizure risk in older adults. Analyzing health records of 60-89 year-olds with asthma or allergies, we found a reduced rate of seizure-related hospitalizations in those starting LTRAs, though this was not as evident in diabetic patients. Our results suggest potential benefits of LTRAs in preventing seizures in older adults with respiratory issues, but further research is needed to confirm these findings.

Association of Plasma Aβ42/Aβ40 Ratio and Late-Onset Epilepsy: Results From the Atherosclerosis Risk in Communities Study

BACKGROUND AND OBJECTIVES

The objective of this study was to determine the relationship between plasma β-amyloid (Aβ), specifically the ratio of 2 Aβ peptides (the Aβ42/Aβ40 ratio, which correlates with increased accumulation of Aβ in the CNS), and late-onset epilepsy (LOE).

METHODS

We used Medicare fee-for-service claims codes from 1991 to 2018 to identify cases of LOE among 1,424 Black and White men and women enrolled in the Atherosclerosis Risk in Communities (ARIC) study cohort. The Aβ42/Aβ40 ratio was calculated from plasma samples collected from ARIC participants in 1993-1995 (age 50-71 years) and 2011-2013 (age 67-90 years). We used survival analysis accounting for the competing risk of death to determine the relationship between late-life plasma Aβ42/Aβ40, and its change from midlife to late life, and the subsequent development of epilepsy. We adjusted for demographics, the apolipoprotein e4 genotype, and comorbidities, including stroke, dementia, and head injury. A low plasma ratio of 2 Aβ peptides, the Aβ42/Aβ40 ratio, correlates with low CSF Aβ42/Aβ40 and with increased accumulation of Aβ in the CNS.

RESULTS

Decrease in plasma Aβ42/Aβ40 ratio from midlife to late life, but not an isolated measurement of Aβ42/Aβ40, was associated with development of epilepsy in later life. For every 50% reduction in Aβ42/Aβ40, there was a 2-fold increase in risk of epilepsy (adjusted subhazard ratio 2.30, 95% CI 1.27-4.17).

DISCUSSION

A reduction in plasma Aβ42/Aβ40 is associated with an increased risk of subsequent epilepsy. Our observations provide a further validation of the link between Aβ, hyperexcitable states, and LOE.

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.

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.

Long-term risk of seizure after posterior reversible encephalopathy syndrome

OBJECTIVE

Patients with posterior reversible encephalopathy syndrome (PRES) can develop seizures during the acute phase. We sought to determine the long-term risk of seizure after PRES.

METHODS

We performed a retrospective cohort study using statewide all-payer claims data from 2016-2018 from nonfederal hospitals in 11 US states. Adults admitted with PRES were compared to adults admitted with stroke, an acute cerebrovascular disorder associated with long-term risk of seizure. The primary outcome was seizure diagnosed during an emergency room visit or hospital admission after the index hospitalization. The secondary outcome was status epilepticus. Diagnoses were determined using previously validated ICD-10-CM codes. Patients with seizure diagnoses before or during the index admission were excluded. We used Cox regression to evaluate the association of PRES with seizure, adjusting for demographics and potential confounders.

RESULTS

We identified 2095 patients hospitalized with PRES and 341,809 with stroke. Median follow-up was 0.9 years (IQR, 0.3-1.7) in the PRES group and 1.0 years (IQR, 0.4-1.8) in the stroke group. Crude seizure incidence per 100 person-years was 9.5 after PRES and 2.5 after stroke. After adjustment for demographics and comorbidities, patients with PRES had a higher risk of seizure than patients with stroke (HR, 2.9; 95% CI, 2.6-3.4). Results were unchanged in a sensitivity analysis that applied a two-week washout period to mitigate detection bias. A similar relationship was observed for the secondary outcome of status epilepticus.

INTERPRETATION

PRES was associated with an increased long-term risk of subsequent acute care utilization for seizure compared to stroke.

Laryngology Outcomes Following Implantable Vagus Nerve Stimulation

Importance

Vagus nerve stimulation (VNS) devices have gained widespread acceptance for treatment of resistant epilepsy and depression. The increasing number of procedures has resulted in an increasing number of iatrogenic injuries to the vagus nerve, which can have a significant effect on vocalization and quality of life.

Objective

To determine the relative frequency of laryngeal adverse effects reported to the US Food and Drug Administration (FDA) after VNS implantation and to analyze associated VNS device problems.

Design, Setting, and Participants

This retrospective cross-sectional analysis queried the FDA Manufacturer and User Facility Device Experience database of adverse events in the US between 1996 and 2020.

Main Outcomes and Measures

The primary outcome was the percent of adverse events reported to the FDA that included patients who received VNS with laryngeal adverse effects and the associated proportion of device problems after VNS surgery.

Results

A total of 12 725 iatrogenic vagus nerve issues were documented after VNS implantation, with apnea (n = 395; 3.1%) being the most common patient problem. Overall, 187 reports of laryngeal adverse effects associated with VNS devices were identified and represented the eighth most common iatrogenic vagus nerve problem reported to the FDA. Laryngeal adverse effects included 78 reports of voice alteration and 57 reports of paresis/paralysis. The VNS device problems frequently associated with laryngeal adverse effects were high impedance (n = 15, 8.02%), incorrect frequency delivery (n = 10, 5.35%), and battery problems (n = 11, 5.88%). The number of laryngeal adverse effect reports per year peaked in 2012 with 43 cases.

Conclusions and Relevance

This cross-sectional study found that although the literature demonstrates that vocal changes occur with nearly all VNS devices, the FDA receives adverse event reports of voice changes. Our results emphasize a potential need to improve patient counseling prior to VNS surgery to better set patient expectations regarding vocal changes and to prevent unnecessary patient concern. In addition, reports of vocal fold paresis/paralysis potentially suggest that patients may benefit from preoperative laryngeal assessment to differentiate preexisting vocal fold paralysis from that caused by VNS surgery.

Association of Head Injury With Late-Onset Epilepsy: Results From the Atherosclerosis Risk in Communities Cohort

BACKGROUND AND OBJECTIVES

Late-onset epilepsy (LOE; i.e., epilepsy starting in later adulthood) affects a significant number of individuals. Head injury is also a risk factor for acquired epilepsy, but the degree to which prior head injury may contribute to LOE is less well understood. Our objective was to determine the association between head injury and subsequent development of LOE.

METHODS

Included were 8,872 participants enrolled in the Atherosclerosis Risk in Communities (ARIC) study with continuous Centers for Medicare Services fee-for-service (FFS) coverage (55.1% women, 21.6% Black). We identified head injuries through 2018 from linked Medicare fee for service claims for inpatient/emergency department care, active surveillance of hospitalizations, and participant self-report. LOE cases through 2018 were identified from linked Medicare FFS claims. We used Cox proportional hazards models to evaluate associations of head injury with LOE, adjusting for demographic, cardiovascular, and lifestyle factors.

RESULTS

The adjusted hazard ratio (HR) for developing LOE after a history of head injury was 1.88 (95% confidence interval [CI] 1.44-2.43). There was evidence for dose-response associations with greater risk for LOE with increasing number of prior head injuries (HR 1.37, 95% CI 1.01-1.88 for 1 prior head injury and HR 3.55, 95% CI 2.51-5.02 for 2+ prior head injuries, compared to no head injuries) and with more severe head injury (HR 2.53, 95% CI 1.83-3.49 for mild injury and HR 4.90, 95% CI 3.15-7.64 for moderate/severe injury, compared to no head injuries). Associations with LOE were significant for head injuries sustained at older age (age ≥67 years: HR 4.01, 95% CI 2.91-5.54), but not for head injuries sustained at younger age (age < 67 years: HR 0.98, 95% CI 0.68-1.41).

DISCUSSION

Head injury was associated with increased risk of developing LOE, particularly when head injuries were sustained at an older age, and there was evidence for higher risk for LOE after a greater number of prior head injuries and after more severe head injuries.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that an increased risk of late-onset epilepsy is associated with head injury and that this risk increases further with multiple and more severe head injuries.

Cluster seizures and status epilepticus in new onset seizures among adult Egyptians

Background

New onset seizure (NOS) is defined as the first seizure within a 24-h period ever experienced by the patient. Cluster seizures (CS) or status epilepticus (SE) can be the first manifestation of epilepsy or it may be a symptom of a brain tumor, a systemic disorder, an infection, or a syndrome. This study aims to determine the etiology of CS and SE in NOS among adult Egyptians. One hundred twenty adult Egyptian patients presented with NOS were enrolled in a hospital-based cross-sectional observational study within a time period of 6 months from March till September 2018. All patients were subjected to neurological examination including mini mental status examination, laboratory, neuroimaging, and electroencephalogram.

Results

Among 120 adult patients presented with NOS, males were prevalent (63%). Older adults (> 55 years) were prevalent (60%). Of the patients, 25% presented by CS, while 11% presented by SE. Post-stroke epilepsy (41%) was the predominant etiology of NOS. Cerebrovascular diseases (CVDs) were the prevalent etiology of SE in NOS (35%). NOS presented by CS were more prevalent among patients with brain tumors (29%) in comparison to CVDs (25%).

Conclusion

CS represented 25% of NOS in adult Egyptian patients. SE is prevalent among 11% of NOS. Despite CVDs being the most prevalent etiology of NOS in adult population (41%) including those presented with SE (35%), brain tumors are the most prevalent etiology of new onset CS (29%).

Etiological profile of new-onset seizures among adult Egyptians

Background

New-onset seizure (NOS) is defined as the first seizure within a 24-h period ever experienced by the patient. A first-ever seizure can be the first manifestation of epilepsy. Or it may be a symptom of a brain tumor, a systemic disorder, an infection, or a syndrome that deserves special attention and treatment. This study aims to identify the etiology of NOS among different age and sex groups of adult Egyptian patients. A hundred and twenty adult Egyptian patients (> 18 years) presented with acute NOS were enrolled in a hospital-based cross-sectional observational study from the emergency room and neurology outpatient clinics of our hospitals within a time period of 6 months from March till September 2018. All patients were subjected to neurological examination, laboratory, neuroimaging, and electroencephalogram investigations.

Results

Among 120 adult patients presented with NOS, males were prevalent (63%). Older adults (age group > 55 years) were the most prevalent cohort (60%). Cerebrovascular diseases (CVDs) were the most common identified etiology of NOS (44.17%), followed by idiopathic epilepsy syndrome (18.33%), symptomatic mainly “metabolic” (11%), brain tumors (9.17%), post-traumatic epilepsy (6.67 %), encephalitis (5.83%), and cryptogenic (5%). Idiopathic epilepsy syndrome was the most common etiology (55.56%) of new-onset seizures among the young adult age group (< 36 years), while CVDs were the most common etiology (65.28%) among older adults (> 55 years). Also, CVDs were the most common etiology among males (43.4%) as well as females (45.4%). However, male predominance was the highest among post-traumatic seizures (87.5%). And female predominance was the highest among brain tumors identified etiology of NOS (54.5%).

Conclusion

NOS among adults are prevalent in elder males. CVDs are the most commonly identified etiology of adult NOS across males and females. Idiopathic epilepsy syndromes are the predominant etiology among younger adults.

Vascular risk factors as predictors of epilepsy in older age: The Framingham Heart Study

OBJECTIVE

Stroke is the most common cause of epilepsy in older age. Subclinical cerebrovascular disease is believed to underlie some of the 30%-50% of late-onset epilepsy without a known cause (Li et al. Epilepsia. 1997;38:1216; Cleary et al. Lancet. 2004;363:1184). We studied the role of modifiable vascular risk factors in predicting subsequent epilepsy among participants ages 45 or older in the Framingham Heart Study (FHS), a longitudinal, community-based study.

METHODS

Participants of the Offspring Cohort who attended FHS exam 5 (1991-1995) were included who were at least 45-years-old at that time, had available vascular risk factor data, and epilepsy follow-up (n = 2986, mean age 58, 48% male). Adjudication of epilepsy cases included review of medical charts to exclude seizure mimics and acute symptomatic seizures. The vascular risk factors studied included hypertension, diabetes mellitus, smoking, and hyperlipidemia. The role of the Framingham Stroke Risk Profile score was also investigated. Cox proportional hazards regression models were used for the analyses.

RESULTS

Fifty-five incident epilepsy cases were identified during a mean of 19 years of follow-up. Hypertension was associated with a near 2-fold risk (hazard ratio [HR]: 1.93, 95% confidence interval [CI]: 1.10-3.37, p = .022) of developing epilepsy, even after adjustment for prevalent and interim stroke. In secondary analysis, excluding patients with normal blood pressure who were receiving anti-HTN (anti-hypertensive) treatment (n = 2613, 50 incident epilepsy cases) the association was (HR: 2.44, 95% CI: 1.36-4.35, p = .003).

SIGNIFICANCE

Our results offer further evidence that hypertension, a potentially modifiable and highly prevalent vascular risk factor in the general population, increases 2- to 2.5-fold the risk of developing late-onset epilepsy.

Incidence rate and risk factors of status epilepticus after stroke

Purpose To evaluate the incidence rate and risk factors for status epilepticus (SE) after stroke (PSSE), including ischaemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH). Methods A meta-analysis was performed using relevant research from databases such as PubMed, Embase, Cochrane Online Library, and Clinicaltrials.gov. The quality of the studies was evaluated by using the quality evaluation criteria of the Agency for Healthcare Research and Quality (AHRQ). All data were pooled by STATA 12.0 software for meta-analysis. Results The review considered 1650 articles, and 17 articles with 2821 instances of SE among 1088087 instances of stroke were included. The incidence rate of SE after stroke was 6.90 per 1000 total strokes (95% CI: 5.58-8.22). By subgroup analysis of SE, the rates were 33.85‰ (95% CI: 13.77-53.94) for non-convulsive status epilepticus (NCSE) and 2.42‰ (95%CI: 1.66-3.19) for generalized convulsive status epilepticus (GCSE). Age, sex, and presence of atrial fibrillation showed no significant difference between the SE group and the non-SE group after stroke. Hypertension and diabetes are associated with a decreased rate of SE. However, African American race, alcohol abuse, and renal disease are associated with an increased rate of SE. Significance There were approximately 6.9 patients with status epilepticus per 1000 strokes. NCSE is more common after stroke and needs more attention. African American race, alcohol abuse and renal disease may be risk factors for PSSE.

Mortality in Patients With Late-Onset Epilepsy: Results From the Atherosclerosis Risk in Communities Study

OBJECTIVE

To determine the risk of mortality and causes of death in persons with late-onset epilepsy (LOE) compared to those without epilepsy in a community-based sample, adjusting for demographics and comorbid conditions.

METHODS

This is an analysis of the prospective Atherosclerosis Risk in Communities (ARIC) study, initiated in 1987-1989 among 15,792 mostly black and white men and women in 4 U.S. communities. We used Centers for Medicare Services fee-for-service claims codes to identify cases of incident epilepsy starting at or after age 67. We used Cox proportional hazards analysis to identify the hazard of mortality associated with LOE and to adjust for demographics and vascular risk factors. We used death certificate data to identify dates and causes of death.

RESULTS

Analyses included 9090 participants, of whom 678 developed LOE during median 11.5 years of follow-up after age 67. Participants who developed LOE were at an increased hazard of mortality compared to those who did not, with adjusted hazard ratio 2.39 (95% CI 2.12-2.71). We observed excess mortality due to stroke, dementia, neurologic conditions, and end-stage renal disease in participants with compared to without LOE. Only 4 deaths (1.1%) were directly attributed to seizure-related causes.

CONCLUSIONS

Persons who develop LOE are at increased risk of death compared to those without epilepsy, even after adjusting for comorbidities. The majority of this excess mortality is due to stroke and dementia.

Cenobamate, a Sodium Channel Inhibitor and Positive Allosteric Modulator of GABAA Ion Channels, for Partial Onset Seizures in Adults: A Comprehensive Review and Clinical Implications

Medical management of epilepsy seeks to eliminate or to reduce the frequency of seizures, help patients maintain a normal lifestyle, and maintain psychosocial and occupational activities, while avoiding the negative side effects of long-term treatment. Current FDA approved drugs have been shown to have similar efficacy; however, they all share a commonality of having side effects that have the potential to significantly reduce a patient’s quality of life. Cenobamate, a newly-FDA approved drug used to treat partial-onset seizures in adult patients, has demonstrated promise in that it works on two proposed mechanisms that are commonly associated with epilepsy. Cenobamate acts as a positive allosteric modulator of the GABA_A ion channels and is effective in reducing repetitive neuronal firing by inhibition of voltage-gated sodium channels, although the complete mechanism of action is currently unknown. The efficacy of Cenobamate with its low toxicity and adverse drug reaction profile emphasizes the need to further evaluate antiepileptic therapies containing sulfamoylphenyl and/or carbamate moieties in their chemical structure. Recent studies have found more patients to be seizure free during the maintenance period when compared to placebo. The most common side effects reported in with Cenobamate are somnolence, dizziness, headache, nausea, and fatigue. There are currently ongoing phase III studies looking to further evaluate the long-term benefits of Cenobamate and investigate adverse events.

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.

Predictors of Mortality in Older Adults With Epilepsy: Implications for Learning Health Systems

OBJECTIVE

To determine the incidence of epilepsy and subsequent 5-year mortality among older adults, as well as characteristics associated with mortality.

METHODS

This was a retrospective cohort study of Medicare beneficiaries age 65 or above with at least 2 years enrollment before January 2009. Incident epilepsy cases were identified in 2009 using ICD-9-CM code-based algorithms; death was assessed through 2014. Cox regression models examined the association between 5-year mortality and incident epilepsy, and whether mortality differed by sociodemographic characteristics or comorbid disorders.

RESULTS

Among the 99,990 of 33,615,037 beneficiaries who developed epilepsy, most were White (79.7%), female (57.3%), urban (80.5%), and without Medicaid (71.3%). The 5-year mortality rate for incident epilepsy was 62.8% (62,838 deaths). In multivariable models, lower mortality was associated with female sex (adjusted hazards ratio [AHR] 0.85, 95% confidence interval [CI] 0.84-0.87), Asian race (AHR 0.82, 95% CI 0.76-0.88), and Hispanic ethnicity (AHR 0.81, 95% CI 0.76-0.84). Hazard of death increased with comorbid disease burden (per 1-point increase: AHR 1.27, 95% CI 1.26-1.27) and Medicaid coinsurance (AHR 1.17, 95% CI 1.14-1.19). Incident epilepsy was particularly associated with higher mortality when diagnosed after another neurologic condition: Parkinson disease (AHR 1.29, 95% CI 1.21-1.38), multiple sclerosis (AHR 2.13, 95% CI 1.79-2.59), dementia (AHR 1.33, 95% CI 1.31-1.36), traumatic brain injury (AHR 1.55, 95% CI 1.45-1.66), and stroke/TIA (AHR 1.20, 95% CI 1.18-1.21).

CONCLUSIONS

Newly diagnosed epilepsy is associated with high 5-year mortality among Medicare beneficiaries. Future studies that parse the interplay of effects from underlying disease, race, sex, and poverty on mortality will be critical in the design of learning health care systems to reduce premature deaths.

Increasing Trends in the Incidence and Prevalence of Epilepsy in Korea

BACKGROUND AND PURPOSE

There have been few reports on recent trends in the occurrence of epilepsy. The aim of this study was to estimate the incidence and prevalence of epilepsy and analyze their annual trends in Korea over the period 2009-2017.

METHODS

This nationwide population-based study was carried out using the National Health Insurance Service of Korea database. A prevalent case was defined as one of a patient receiving a prescription of anticonvulsants under the diagnostic codes for epilepsy or seizure. An incident case was ascertained by confirming the absence of any epilepsy-related diagnostic codes and anticonvulsant prescription for 2 years or more before the operational definition for a prevalent case was met. Alternative operational definitions for epilepsy were tested. The temporal trends of the incidence and prevalence of epilepsy were analyzed using a Poisson regression model, and are expressed as average annual percentage changes (AAPCs).

RESULTS

The incidence of epilepsy increased from 28.7/100,000 persons in 2009 to 35.4/100,000 persons in 2017. The prevalence increased gradually from 3.4/1,000 persons in 2009 to 4.8/1,000 persons in 2017. These increasing trends were more evident among elderly subjects aged ≥75 years and in those who had codes for epilepsy or seizure as an additional diagnosis. Age standardization revealed a less prominent but still increasing trend in both incidence (AAPC=0.48%) and prevalence (AAPC=3.11%).

CONCLUSIONS

There have been increasing trends in both the prevalence and incidence of epilepsy in Korea between 2009 and 2017. This finding appears to be related to societal aging and the high incidence of symptomatic epilepsy in the elderly population.

Cognitive decline in older adults with epilepsy: The Cardiovascular Health Study

OBJECTIVE

Cognitive decline is a major concern for older adults with epilepsy. Whether and how much faster older adults with epilepsy experience cognitive decline beyond expected age-related cognitive change remain unclear. We sought to estimate and compare rates of cognitive decline in older adults with and without epilepsy.

METHODS

The Cardiovascular Health Study is a population-based longitudinal cohort study of 5888 US adults aged 65+. Cognitive function was assessed annually with Modified Mini-Mental State Exam (3MS) and Digit Symbol Substitution Test (DSST). We used linear mixed models to estimate average rates of decline in 3MS and DSST scores by epilepsy status (prevalent, incident, or no epilepsy), adjusted for risk factors associated with cognitive decline.

RESULTS

The rate of decline in 3MS was significantly faster in prevalent epilepsy (P < .001) and after incident epilepsy (P = .002) compared with no epilepsy. Prevalent epilepsy and apolipoprotein E gene (APOE) ε4 (ApoE4) had a synergistic interaction, whereby prevalent epilepsy and ApoE4 together were associated with 1.51 points faster annual decline in 3MS than would be expected if prevalent epilepsy and ApoE4 did not interact (P < .001). Older adults with prevalent epilepsy had a significantly lower initial DSST score and faster rate of decline compared to those with no epilepsy (P < .001).

SIGNIFICANCE

Faster decline in global cognitive ability seen in this study validates concerns of patients. ApoE4 allele status was an effect modifier of the relationship between cognitive decline and prevalent epilepsy. Further research is warranted to explore biological mechanisms and possible interventions to mitigate cognitive decline.

Dementia in late-onset epilepsy: The Atherosclerosis Risk in Communities study

OBJECTIVE

To determine the risk of dementia after the development of late-onset epilepsy.

METHODS

We used data from the Atherosclerosis Risk in Communities (ARIC) cohort study, which started in 1987 to 1989 with 15,792 mostly Black and White men and women from 4 US communities. We identified late-onset epilepsy (LOE; seizures starting at age 67 or later) from linked Medicare claims data. We used a Cox proportional hazards regression model to evaluate associations between LOE and dementia through 2017 as ascertained from neuropsychological testing, interviews, and hospital discharge surveillance, and we used multinomial logistic regression to assess the risk of dementia and mild cognitive impairment in the subset with full neuropsychological assessments available. We adjusted for demographics and vascular and Alzheimer disease risk factors.

RESULTS

Of 9,033 ARIC participants with sufficient Medicare coverage data (4,980 [55.1%] female, 1993 [22.1%] Black), 671 met the definition of LOE. Two hundred seventy-nine (41.6%) participants with and 1,408 (16.8%) without LOE developed dementia (p < 0.001). After a diagnosis of LOE, the adjusted hazard ratio for developing subsequent dementia was 3.05 (95% confidence interval 2.65-3.51). The median time to dementia ascertainment after the onset of LOE was 3.66 years (quartile 1-3, 1.28-8.28 years).

INTERPRETATION

The risk of incident dementia is substantially elevated in individuals with LOE. Further work is needed to explore causes for the increased risk of dementia in this growing population.

Bi-directional association between epilepsy and dementia: The Framingham Heart Study

OBJECTIVE

To assess the risk of incident epilepsy among participants with prevalent dementia and the risk of incident dementia among participants with prevalent epilepsy in the Framingham Heart Study (FHS).

METHODS

We analyzed prospectively collected data in the Original and Offspring FHS cohorts. To determine the risk of developing epilepsy among participants with dementia and the risk of developing dementia among participants with epilepsy, we used separate, nested, case-control designs and matched each case to 3 age-, sex- and FHS cohort-matched controls. We used Cox proportional hazards regression analysis, adjusting for sex and age. In secondary analysis, we investigated the role of education level and APOE ε4 allele status in modifying the association between epilepsy and dementia.

RESULTS

A total of 4,906 participants had information on epilepsy and dementia and dementia follow-up after age 65. Among 660 participants with dementia and 1,980 dementia-free controls, there were 58 incident epilepsy cases during follow-up. Analysis comparing epilepsy risk among dementia cases vs controls yielded a hazard ratio (HR) of 1.82 (95% confidence interval 1.05-3.16, p = 0.034). Among 43 participants with epilepsy and 129 epilepsy-free controls, there were 51 incident dementia cases. Analysis comparing dementia risk among epilepsy cases vs controls yielded a HR of 1.99 (1.11-3.57, p = 0.021). In this group, among participants with any post-high school education, prevalent epilepsy was associated with a nearly 5-fold risk for developing dementia (HR 4.67 [1.82-12.01], p = 0.001) compared to controls of the same educational attainment.

CONCLUSIONS

There is a bi-directional association between epilepsy and dementia. with either condition carrying a nearly 2-fold risk of developing the other when compared to controls.

Late-onset epilepsy and 25-year cognitive change: The Atherosclerosis Risk in Communities (ARIC) study

OBJECTIVE

To define the association between late-onset epilepsy (LOE) and 25-year change in cognitive performance.

METHODS

The Atherosclerosis Risk in Communities (ARIC) study is a multicenter longitudinal cohort study with participants from four U.S. communities. From linked Medicare claims, we identified cases of LOE, defined as ≥2 seizure-related diagnostic codes starting at age ≥67. The ARIC cohort underwent evaluation with in-person visits at intervals of 3-15 years. Cognition was evaluated 4 times over >25 years (including before the onset of seizures) using the Delayed Word Recall Test (DWRT), Digit Symbol Substitution Test (DSST), and Word Fluency Test (WFT); a global z-score was also calculated. We compared the longitudinal cognitive changes of participants with and without LOE, adjusting for demographics and LOE risk factors.

RESULTS

From 8033 ARIC participants with midlife cognitive testing and Medicare claims data available (4523 [56%] female, 1392 [17%] Black), we identified 585 cases of LOE. The rate of cognitive decline was increased on all measures in the participants who developed LOE compared to those without LOE. On the measure of global cognition, participants with LOE declined by -0.43 z-score points more over 25 years than did participants without epilepsy (95% confidence interval [CI] -0.59 to -0.27). Prior to the onset of seizures, cognitive decline was more rapid on the DWRT, DSST, and global z-scores in those who would later develop LOE than it was in non-LOE participants. Results were similar after excluding data from participants with dementia.

SIGNIFICANCE

Global cognition, verbal memory, executive function, and word fluency declined faster over time in persons developing LOE than without LOE. Declines in cognition preceding LOE suggest these are linked; it will be important to investigate causes for midlife cognitive declines associated with LOE.

The health burden of non-communicable neurological disorders in the USA between 1990 and 2017

In this observational study, using the Global Burden of Disease and Risk Factors Study, we aimed to (i) report the magnitude of health loss due to non-communicable neurological disorders in the USA in 2017 by sex, age, years and States and (ii) to identify non-communicable neurological disorders attributable environmental, metabolic and behavioural risk factors. We provide estimates of the burden of non-communicable neurological disorders by reporting disability-adjusted life-years and their trends from 1990 to 2017 by age and sex in the USA. The non-communicable neurological disorders include migraines, tension-type headaches, multiple sclerosis, Alzheimer's disease and other dementias, Parkinson's disease, epilepsy, motor neuron diseases and other neurological disorders. In 2017, the global burdens of non-communicable neurological disorders were 1444.41 per 100 000, compared to the USA burden of 1574.0. Migraine was the leading age-standardized disability-adjusted life-years 704.7 per 100 000, with Alzheimer's disease and other dementias (41.8.7), and epilepsy (123.8) taking the second and third places, respectively. Between 1990 and 2017, the age-standardized disability-adjusted life-years rates for aggregate non-communicable neurological disorders relative to all cause increased by 3.42%. More specifically, this value for motor neuron diseases, Parkinson's disease and multiple sclerosis increase by 20.9%, 4.0%, 2.47%, 3.0% and 1.65%, respectively. In 2017, the age-standardized disability-adjusted life-years rates for the aggregate non-communicable neurological disorders was significantly higher in females than the males (1843.5 versus 1297.3 per 100 000), respectively. The age-standardized disability-adjusted life-years rates for migraine were the largest in both females (968.8) and males were (432.5) compared to other individual non-communicable neurological disorders. In the same year, the leading non-communicable neurological disorders age-standardized disability-adjusted life-years rates among children ≤9 was epilepsy (216.4 per 100 000). Among the adults aged 35-60 years, it was migraine (5792.0 per 100 000), and among the aged 65 and above was Alzheimer's disease and other dementias (78 800.1 per 100 000). High body mass index, smoking, high fasting plasma glaucous and alcohol use were the attributable age-standardized disability-adjusted life-years risks for aggregate and individual non-communicable neurological disorders. Despite efforts to decrease the burden of non-communicable neurological disorders in the USA, they continue to burden the health of the population. Children are most vulnerable to epilepsy-related health burden, adolescents and young adults to migraine, and elderly to Alzheimer's disease and other dementias and epilepsy. In all, the most vulnerable populations to non-communicable neurological disorders are females, young adults and the elderly.

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.

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.

Epilepsy in the elderly: Unique challenges in an increasingly prevalent population

Elderly individuals (aged at least 60 or 65 years) represent a rapidly growing segment of the population. The incidence and prevalence of epilepsy is higher in this age group than in any other. Diagnosing epilepsy in the elderly can be challenging because the causes and clinical manifestations of seizures often differ as compared with younger individuals. Particular differential diagnoses, such as syncope and amyloid spells, are commonly encountered in the elderly population. A diagnosis of epilepsy has important implications in the older adult, many of which already present a variety of concomitant complex medical problems, such as cognitive impairment, comorbid cerebrovascular disease, and frailty. The treatment of epilepsy in the elderly is complicated by a variety of factors related to aging, including physiological changes, medical comorbidities, and polypharmacy. In this narrative review, we will address the descriptive epidemiology, clinical presentation, differential diagnosis, diagnostic evaluation, treatment, and prognosis of epilepsy in the elderly individual.

An empirical assessment of appearance descriptors applied to MRI for automated diagnosis of TLE and MCI

OBJECTIVE

Differential diagnosis of mild cognitive impairment MCI and temporal lobe epilepsy TLE is a debated issue, specifically because these conditions may coincide in the elderly population. We evaluate automated differential diagnosis based on characteristics derived from structural brain MRI of different brain regions.

METHODS

In 22 healthy controls, 19 patients with MCI, and 17 patients with TLE we used scale invariant feature transform (SIFT), local binary patterns (LBP), and wavelet-based features and investigate their predictive performance for MCI and TLE.

RESULTS

The classification based on SIFT features resulted in an accuracy of 81% of MCI vs. TLE and reasonable generalizability. Local binary patterns yielded satisfactory diagnostic performance with up to 94.74% sensitivity and 88.24% specificity in the right Thalamus for the distinction of MCI vs. TLE, but with limited generalizable. Wavelet features yielded similar results as LPB with 94.74% sensitivity and 82.35% specificity but generalize better.

SIGNIFICANCE

Features beyond volume analysis are a valid approach when applied to specific regions of the brain. Most significant information could be extracted from the thalamus, frontal gyri, and temporal regions, among others. These results suggest that analysis of changes of the central nervous system should not be limited to the most typical regions of interest such as the hippocampus and parahippocampal areas. Region-independent approaches can add considerable information for diagnosis. We emphasize the need to characterize generalizability in future studies, as our results demonstrate that not doing so can lead to overestimation of classification results.

LIMITATIONS

The data used within this study allows for separation of MCI and TLE subjects using a simple age threshold. While we present a strong indication that the presented method is age-invariant and therefore agnostic to this situation, new data would be needed for a rigorous empirical assessment of this findings.

Racial differences in adult-onset MRI-negative temporal lobe epilepsy

OBJECTIVE

We recently detected a significant racial difference in our population with temporal lobe epilepsy (TLE) at the University of Alabama at Birmingham (UAB) seizure monitoring unit. We found that Black patients were more likely than their White counterparts to carry a TLE diagnosis. Using this same patient population, we focus on the patients with TLE to better describe the relationship between race and epidemiology in this population.

METHODS

We analyzed the data from patients diagnosed with TLE admitted to the UAB seizure monitoring unit between January 2000 and December 2011. For patients with a video electroencephalography (EEG) confirmed diagnosis of TLE (n = 385), basic demographic information including race and magnetic resonance imaging (MRI) findings were collected. Descriptive statistics and multivariate logistic regression were used to explore the relationship between MRI findings, demographic data, and race.

RESULTS

For Black patients with TLE, we found that they were more likely to be female (odds ratio [OR] = 1.91, 95% confidence interval [CI]: 1.14-3.19), have seizure onset in adulthood (OR = 2.39, 95% CI: 1.43-3.19), and have normal MRIs (OR = 1.69, 95% CI: 1.04-2.77) compared to White counterparts with TLE after adjusting for covariates.

CONCLUSIONS

These data suggest that Black race (compared to White) is associated with higher expression of adult-onset MRI-negative TLE, an important subtype of epilepsy with unique implications for evaluation, treatment, and prognosis. If validated in other cohorts, the findings may explain the lower reported rates of epilepsy surgery utilization among Blacks. The racial differences in surgical utilization could be due to a greater prevalence of an epilepsy that is less amenable to surgical resection rather than to cultural differences or access to care.

Association Between Midlife Risk Factors and Late-Onset Epilepsy: Results From the Atherosclerosis Risk in Communities Study

Importance

The incidence of epilepsy is higher in older age than at any other period of life. Stroke, dementia, and hypertension are associated with late-onset epilepsy; however, the role of other vascular and lifestyle factors remains unclear.

Objective

To identify midlife vascular and lifestyle risk factors for late-onset epilepsy.

Design, Setting, and Participants

The Atherosclerosis Risk in Communities (ARIC) study is a prospective cohort study of 15 792 participants followed up since 1987 to 1989 with in-person visits, telephone calls, and surveillance of hospitalizations (10 974 invited without completing enrollment). The ARIC is a multicenter study with participants selected from 4 US communities. This study included 10 420 black or white participants from ARIC with at least 2 years of Medicare fee-for-service coverage and without missing baseline data. Data were analyzed betweeen April 2017 and May 2018.

Exposures

Demographic, vascular, lifestyle, and other possible epilepsy risk factors measured at baseline (age 45-64 years) were evaluated in multivariable survival models including demographics, vascular risk factors, and lifestyle risk factors.

Main Outcomes and Measures

Time to development of late-onset epilepsy (2 or more International Classification of Diseases, Ninth Revision codes for epilepsy or seizures starting at 60 years or older in any claim [hospitalization or outpatient Medicare through 2013]), with first code for seizures after at least 2 years without code for seizures.

Results

Of the 10 420 total participants (5878 women [56.4%] and 2794 black participants [26.8%]; median age 55 years at first visit), 596 participants developed late-onset epilepsy (3.33 per 1000 person-years). The incidence was higher in black than in white participants (4.71; 95% CI, 4.12-5.40 vs 2.88; 95% CI, 2.60-3.18 per 1000 person-years). In multivariable analysis, baseline hypertension (hazard ratio [HR], 1.30; 95% CI, 1.09-1.55), diabetes (HR, 1.45; 95% CI, 1.17-1.80), smoking (HR, 1.09; 95% CI, 1.01-1.17), apolipoprotein E ε4 genotype (1 allele HR, 1.22; 95% CI, 1.02-1.45; 2 alleles HR, 1.95; 95% CI, 1.35-2.81), and incident stroke (HR, 3.38; 95% CI, 2.78-4.10) and dementia (HR, 2.56; 95% CI, 2.11-3.12) were associated with an increased risk of late-onset epilepsy, while higher levels of physical activity (HR, 0.90; 95% CI, 0.83-0.98) and moderate alcohol intake (HR, 0.72; 95% CI, 0.57-0.90) were associated with a lower risk. Results were similar after censoring individuals with stroke or dementia.

Conclusions and Relevance

Potentially modifiable risk factors in midlife and the APOE ε4 genotype were positively associated with risk of developing late-onset epilepsy. Although stroke and dementia were both associated with late-onset epilepsy, vascular and lifestyle risk factors were significant even in the absence of stroke or dementia.

Epilepsy in the Elderly: Treatment and Consideration of Comorbid Diseases

Epilepsy is the third most common neurological disorder affecting older adults after stroke and dementia, and the incidence of epilepsy is increasing rapidly in this population. A further increase in the incidence and prevalence of epilepsy is expected in aging societies. The establishment of a correct differential diagnosis between epilepsy and other seizure disorders that are common in the elderly is crucial. The symptoms of seizures in the elderly may be different from those in younger populations. The diagnosis is difficult, probably because of nonspecific characteristics, short-term symptoms, and absence of witnesses. There are three important issues in the treatment of epilepsy in the elderly: changes in pharmacokinetic parameters, polytherapy (including non-antiepileptic and antiepileptic drugs), and susceptibility to adverse drug effects. Antiepileptic drugs (AEDs) with fewer adverse effects, including cognitive effects, and AEDs without significant pharmacokinetic drug interactions are needed. Several studies found that stroke was strongly associated with a high incidence of early seizures and epilepsy. Stroke is also one of the major causes of status epilepticus. Cortical involvement and large lesions are strongly associated with the development of seizures and epilepsy. The severity of the initial neurological deficit is a strong clinical predictor of seizures after ischemic stroke. The optimal quality of life of dementia patients cannot be achieved without a proper diagnosis of coexisting epilepsy.

Epilepsy Among Elderly Medicare Beneficiaries: A Validated Approach to Identify Prevalent and Incident Epilepsy

BACKGROUND

Uncertain validity of epilepsy diagnoses within health insurance claims and other large datasets have hindered efforts to study and monitor care at the population level.

OBJECTIVES

To develop and validate prediction models using longitudinal Medicare administrative data to identify patients with actual epilepsy among those with the diagnosis.

RESEARCH DESIGN, SUBJECTS, MEASURES

We used linked electronic health records and Medicare administrative data including claims to predict epilepsy status. A neurologist reviewed electronic health record data to assess epilepsy status in a stratified random sample of Medicare beneficiaries aged 65+ years between January 2012 and December 2014. We then reconstructed the full sample using inverse probability sampling weights. We developed prediction models using longitudinal Medicare data, then in a separate sample evaluated the predictive performance of each model, for example, area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity.

RESULTS

Of 20,945 patients in the reconstructed sample, 2.1% had confirmed epilepsy. The best-performing prediction model to identify prevalent epilepsy required epilepsy diagnoses with multiple claims at least 60 days apart, and epilepsy-specific drug claims: AUROC=0.93 [95% confidence interval (CI), 0.90-0.96], and with an 80% diagnostic threshold, sensitivity=87.8% (95% CI, 80.4%-93.2%), specificity=98.4% (95% CI, 98.2%-98.5%). A similar model also performed well in predicting incident epilepsy (k=0.79; 95% CI, 0.66-0.92).

CONCLUSIONS

Prediction models using longitudinal Medicare data perform well in predicting incident and prevalent epilepsy status accurately.

Prevalence and Economic Burden of Epilepsy in the Institutionalized Medicare Fee-for-Service Population

BACKGROUND

Based on data from 2003 to 2007, the prevalence of epilepsy was significantly higher in the institutionalized elderly population than in the noninstitutionalized population, but the recent prevalence and economic impact of epilepsy specifically in the institutionalized Medicare population have not been reported.

OBJECTIVES

To estimate the prevalence and economic burden of epilepsy and inpatient utilization rates among institutionalized Medicare beneficiaries and to provide a 10-year projection of their population size and the associated costs.

METHODS

We performed a cross-sectional analysis of the institutionalized Medicare population with and without epilepsy using Medicare 5% sample claims data from 2013 and 2014. The identification of epilepsy required ≥1 qualifying claims with an epilepsy diagnosis, or ≥2 qualifying claims ≥30 days apart with a diagnosis of convulsion, in 2014. Institutionalized status was identified by having ≥6 consecutive months of nursing facility claims in 2013 or 2014. Inpatient admissions and 30-day readmissions, average allowed costs, and risk-adjusted incremental costs of epilepsy were calculated and compared between the institutionalized population of Medicare beneficiaries with and without epilepsy. The 2015 Medicare 100% and 5% sample data and inputs from other external sources were used to project the 10-year trends in the size and cost of the institutionalized Medicare population with epilepsy.

RESULTS

The prevalence of epilepsy in 2014 was 11.1% in the institutionalized Medicare population. The institutionalized population with epilepsy had significantly higher per-patient per-month (PPPM) costs ($3479 vs $2381, respectively; P <.001), inpatient admissions per 1000 beneficiaries (1105 vs 697, respectively; P <.001), and 30-day readmissions per 1000 beneficiaries (287 vs 145, respectively; P <.001) versus the institutionalized population without epilepsy. The risk-adjusted incremental cost of epilepsy for the institutionalized population was $507.33 PPPM. Based on our model, between 2017 and 2027 an 18% increase in size and a 72% increase in cost are projected for the institutionalized Medicare beneficiaries with epilepsy.

CONCLUSION

The high cost and inpatient resource utilization, as well as the projected growth of the institutionalized Medicare population with epilepsy highlight the need for further investigation of care management opportunities to reduce the cost burden associated with this condition.

Association between white matter hyperintensities, cortical volumes, and late-onset epilepsy

OBJECTIVE

To identify the association between brain vascular changes and cortical volumes on MRI and late-onset epilepsy.

METHODS

In 1993-1995, 1,920 participants (median age 62.7, 59.9% female) in the community-based Atherosclerosis Risk in Communities (ARIC) Study underwent MRI, and white matter hyperintensities were measured. In addition, in 2011-2013, 1,964 ARIC participants (median age 72.4, 61.1% female) underwent MRI, and cortical volumes and white matter hyperintensities were measured. We identified cases of late-onset epilepsy (starting at age 60 or later) from ARIC hospitalization records and Medicare claims data. Using the 1993-1995 MRI, we evaluated the association between white matter hyperintensities and subsequent epilepsy using survival analysis. We used the 2011-2013 MRI to conduct cross-sectional logistic regression to examine the association of cortical volumes and white matter hyperintensities with late-onset epilepsy. All models were adjusted for demographics, hypertension, diabetes, smoking, and APOE ε4 allele status.

RESULTS

Ninety-seven ARIC participants developed epilepsy after having an MRI in 1993-1995 (incidence 3.34 per 1,000 person-years). The degree of white matter hyperintensities measured at ages 49-72 years was associated with the risk of late-onset epilepsy (hazard ratio 1.27 per age-adjusted SD, 95% confidence interval [CI] 1.06-1.54). Lower cortical volume scores were associated cross-sectionally with higher odds of late-onset epilepsy (odds ratio 1.87, 95% CI 1.16-3.02) per age-adjusted SD.

CONCLUSIONS

This study demonstrates associations between earlier-life white matter hyperintensities on MRI and later-life incident epilepsy, and between cortical volumes measured later in life and late-onset epilepsy. These findings may help illuminate the causes of late-onset epilepsy.

Incidence of epilepsy and associated factors in elderly patients in Germany

AIMS

Little is known about the recent epidemiology of epilepsy in the elderly in Germany. Therefore, the goal of this study was to analyze the incidence of epilepsy and associated factors in elderly patients followed in general practices in this country.

METHODS

The incidence of epilepsy was estimated using data from all patients aged ≥60 years who were followed in 1203 general practices in Germany in 2017 (IQVIA Disease Analyzer database). The association between predefined variables and epilepsy was further studied using a case-control design (n = 4690 matched pairs). Cases were patients aged ≥60 years who had received a first diagnosis of epilepsy in general practices between 2015 and 2017 (index date). Controls without epilepsy were matched (1:1) to cases by age, gender, index year, and physician.

RESULTS

The incidence of epilepsy was 157 per 100,000 elderly persons. This incidence increased with age (92 per 100,000 persons in patients aged 60-65 years versus 311 in those aged >90 years) and was higher in men (166) than in women (150). The three disorders that had the strongest association with epilepsy were subarachnoid, intracerebral or intracranial hemorrhage (odds ratio [OR] = 3.31), stroke, including transient ischemic attack (OR = 2.32), and mental and behavioral disorders due to use of alcohol (OR = 2.20). In addition, there was a positive association between atypical neuroleptics and epilepsy (OR = 2.40).

CONCLUSIONS

The incidence of epilepsy was high and increased with age in elderly patients followed in general practices in Germany. Addressing identified risk factors may help reduce the risk of developing epilepsy.

Long-term risk of seizures among cardiac arrest survivors

INTRODUCTION

The long-term risk of seizures in cardiac arrest survivors is not established. We hypothesized that survivors of cardiac arrest face an increased long-term risk for seizures.

METHODS

We performed a retrospective cohort study using 2008-2015 claims data from a nationally representative 5% sample of Medicare beneficiaries ≥66 years-old. Our exposure of interest was a hospital diagnosis code of cardiac arrest, defined by previously validated ICD-9-CM codes. Since we were interested in long-term risk, we excluded patients with a history of seizure, and those who were diagnosed with a seizure during hospitalization or died during the index hospitalization. Our outcome was a diagnosis of seizure. Survival statistics were used to calculate seizure incidence and Cox proportional hazards models were used to determine the association between cardiac arrest and long-term seizures after adjustment for demographics and Charlson comorbidities.

RESULTS

Among 1,764,508 beneficiaries with a mean 4.5 years of follow-up, we identified 57,437 patients with cardiac arrest who survived to discharge without a seizure. The annual incidence of seizures was 1.26% (95% confidence interval [CI], 1.20-1.33%) compared to 0.61% (95% CI, 0.61-0.62%) in other Medicare patients. In unadjusted analysis, cardiac arrest was associated with an increased risk of post-discharge seizures (hazard ratio [HR], 1.8; 95% CI, 1.7-1.9), but the association was lost after adjustment for demographics and comorbidities (HR 0.9; 95% CI, 0.9-1.0; P = 0.12).

CONCLUSION

The long-term risk of seizures was not elevated in patients with cardiac arrest who survived to hospital discharge without a seizure.

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.