Descriptive epidemiology of epilepsy in the U.S. population: A different approach

Prevalence, demographic and spatial distribution of treated epilepsy in France in 2020: a study based on the French national health data system

BACKGROUND

Although still incomplete, the epidemiology of epilepsy shows substantial variations in the burden of the condition according to demographic, social and territorial characteristics. This study aimed to estimate the prevalence of treated epilepsy and to investigate its demographic and spatial distribution in 2020 in France, a country where the nationwide epidemiological situation of the condition remains largely unknown.

METHODS

We used the French national health data system, which covers nearly the entire population residing in France (over 67 million of inhabitants in metropolitan and overseas departments). Prevalent cases were identified using long-term disease status, hospitalisation for epilepsy (ICD-10 codes G40 or G41), and reimbursements for antiseizure medications and electroencephalograms.

RESULTS

In 2020, we identified 685,122 epilepsy cases, corresponding to an overall prevalence of 10.2 per 1000 inhabitants [95% confidence interval 10.1-10.2], with similar rates in men and women. Estimates were found to increase with age, with an accelerated rise in the second half of the life, which occurred earlier in men than in women. We observed a monotonic gradient of variation with socio-economic deprivation (in non-military metropolitan subjects aged 18-54 years) as well as territorial heterogeneity, with the mountainous centre of France as well as some French overseas departments having the highest prevalence.

CONCLUSIONS

Our results revise upwards the estimation of epilepsy prevalence in France, showing that it now ranks among the highest in developed countries. Our study also confirms the important socio-territorial heterogeneity of the condition that reflects health inequalities in this country.

Epidemiology of focal onset seizures in children aged >1 month to 4 years in Europe, United States, and Canada: A literature review

The present study aims to report the currently available epidemiology of focal onset seizures in children aged >1 month to 4 years with the help of a literature review. The terms 'seizure*' OR 'epilepsy' combined with pediatric and epidemiology terms were used to search Embase, PubMed, and Web of Science up to November 16, 2021. Due to the scarcity of epidemiology data on focal onset seizures, the incidence and prevalence were estimated using the proportion of focal onset seizures in epilepsy patients from the most recently published articles. The estimated annual incidence per 100,000 children of focal onset seizures in children of 0-4 years of age ranged from 25.1 (95 % confidence interval [CI] 18.9-32.7) in the United Kingdom to 111.8 in the United States. The estimated period prevalence of focal onset seizures in children 0-4 years of age ranged from 0.15 % (99 % CI 0.13-0.18) in Canada to 0.61 % in the United States. Neurodevelopmental outcomes and psychiatric disorders were the most commonly reported comorbidities in children with epilepsy of age 0-4 years. Presence of focal onset seizures in children with different epilepsy syndromes needs to be thoroughly considered in the treatment planning of this population of interest.

Utilization of Antiseizure Medications in Women of Childbearing Age With Epilepsy and Nonepilepsy Indications: A Retrospective Cohort Study

BACKGROUND AND OBJECTIVES

Antiseizure medications (ASMs) are among the most commonly prescribed teratogenic drugs in women of childbearing age. Limited data exist on utilization patterns across different indications for therapy and for the newer-generation ASMs in this population. Thus, we assessed the pattern of ASM use in women of childbearing age with epilepsy and nonepilepsy indications (pain and psychiatric disorders).

METHODS

We conducted a retrospective analysis of deidentified administrative data submitted to the Optum Clinformatics database. Eligible participants included women aged 12-50 years who filled ASMs between year 2011 and 2017. Participants were followed from date of index prescription filled to study end or insurance disenrollment, whichever came first. For the overall cohort and potential therapy indications, we assessed the type and frequency of ASMs filled; proportion of participants on monotherapy, polytherapy, or treatment switching; and duration of continuous use. Trends were characterized using annual percent change from study start to study end.

RESULTS

Our analysis included 465,131 participants who filled 603,916 distinct ASM prescriptions. At baseline, most of the participants had chronic pain (51.0%) and psychiatric disorders (32.7%), with epilepsy the least common (0.9%). The most frequently dispensed were diazepam (24.3%), lorazepam (20.1%), gabapentin (17.4%), clonazepam (12.7%), topiramate (11.3%), and lamotrigine (4.6%). Significant linear increase in trends were observed with gabapentin (annual percent change [95% CI]: 8.4 [7.3-9.4]; p < 0.001) and levetiracetam (3.4 [0.7-6.2]; p = 0.022) and decreasing trends for diazepam (-3.5 [-2.4 to 4.5]; p < 0.001) and clonazepam (-3.4 [-2.3 to 4.5]; p = 0.001). No significant change in trend was observed with valproate (-0.4 [-2.7 to 1.9]; p = 0.651), while nonlinear changes in trends were observed with lorazepam, topiramate, lamotrigine, and pregabalin.

DISCUSSION

Decreasing trends were observed with older ASMs in the overall cohort and across the potential indications for therapy. Conversely, increasing trends were seen with the newer ASMs. Considering the risk of teratogenicity associated with the newer medications largely unknown, counseling and education in addition to a careful consideration of the benefits vs potential risks should remain pivotal when prescribing ASMs for women of childbearing age.

Comparison of long-term survival with continued medical therapy, vagus nerve stimulation, and cranial epilepsy surgery in paediatric patients with drug-resistant epilepsy in the USA: an observational cohort study

BACKGROUND

Long-term survival in paediatric epilepsy is incompletely characterised. A better understanding of treatment effects on mortality in paediatric patients with drug-resistant epilepsy is needed for health-care decision making. We aimed to compare the long-term survival rates associated with antiseizure medications only, antiseizure medications plus vagus nerve stimulation (VNS), and antiseizure medications plus cranial epilepsy surgery in paediatric patients with drug-resistant epilepsy using a large national administrative database in the USA.

METHODS

In this observational cohort study, patients aged 0-17 years who were diagnosed with drug-resistant epilepsy using International Classificiaton of Diseases codes between Jan 1, 2004, and Dec 31, 2020, were identified from the Pediatric Health Information System, an administrative database that contains inpatient, emergency department, ambulatory, and observation unit encounter-level data from more than 49 children's hospitals in the USA. Patients treated with at least three types of antiseizure medications were included in the medical therapy cohort, those treated with antiseizure medications plus VNS were included in the VNS cohort, and those treated with antiseizure medications plus cranial epilepsy surgery were included in the surgery cohort. Participants were followed up until the date of their last clinical encounter, in-hospital death, or Dec 31, 2020. Inverse probability of treatment weighting (IPTW) was used to balance baseline demographics and clinical characteristics between treatment groups. The unconditional probabilities of survival were estimated by weighted Kaplan-Meier analysis. A weighted Cox proportional hazards model was used to investigate the association between risk of overall death and age, sex, geographical region, race and ethnicity, comorbidity, primary diagnosis, insurance, and treatment.

FINDINGS

This study included 10 240 patients treated with antiseizure medications only, 5019 patients treated with antiseizure medications plus VNS, and 3033 patients treated with antiseizure medications plus cranial epilepsy surgery. The median age of paediatric patients was 7 years (IQR 4-12) in the medical therapy cohort, 9 years (6-13) in the VNS cohort, and 9 years (5-13) in the surgery cohort. The IPTW-adjusted probabilities of surviving beyond 10 years were 89·27% (95% CI 87·71-90·85) for the medical therapy cohort, 92·65% (90·62-94·72) for the VNS cohort, and 98·45% (97·53-99·38) for the surgery cohort. The difference in survival probabilities was significant (log-rank p<0·0001). Compared with the medical therapy cohort, the IPTW-adjusted hazard ratio for overall death was 0·60 (95% CI 0·50-0·74) for the VNS cohort and 0·19 (0·10-0·33) for the surgery cohort.

INTERPRETATION

Paediatric patients with drug-resistant epilepsy who underwent cranial epilepsy surgery or VNS had a higher survival rate than those who received only medical treatment. These findings highlight the importance of a multidisciplinary comprehensive team approach to the treatment of epilepsy, which includes tailored evaluation and deployment of medical and surgical treatment options for patients with this challenging disease.

FUNDING

None.

The epidemiology of epilepsy in older adults: A narrative review by the ILAE Task Force on Epilepsy in the Elderly

In an aging world, it is important to know the burden of epilepsy affecting populations of older persons. We performed a selective review of epidemiological studies that we considered to be most informative, trying to include data from all parts of the world. We emphasized primary reports rather than review articles. We reviewed studies reporting the incidence and prevalence of epilepsy that focused on an older population as well as studies that included a wider age range if older persons were tabulated as a subgroup. There is strong evidence that persons older than approximately 60 years incur an increasing risk of both acute symptomatic seizures and epilepsy. In wealthier countries, the incidence of epilepsy increases sharply after age 60 or 65 years. This phenomenon was not always observed among reports from populations with lower socioeconomic status. This discrepancy may reflect differences in etiologies, methods of ascertainment, or distribution of ages; this is an area for more research. We identified other areas for which there are inadequate data. Incidence data are scarcer than prevalence data and are missing for large areas of the world. Prevalence is lower than would be expected from cumulative incidence, possibly because of remissions, excess mortality, or misdiagnosis of acute symptomatic seizures as epilepsy. Segmentation by age, frailty, and comorbidities is desirable, because "epilepsy in the elderly" is otherwise too broad a concept. Data are needed on rates of status epilepticus and drug-resistant epilepsy using the newer definitions. Many more data are needed from low-income populations and from developing countries. Greater awareness of the high rates of seizures among older adults should lead to more focused diagnostic efforts for individuals. Accurate data on epilepsy among older adults should drive proper allocation of treatments for individuals and resources for societies.

Disparities in pediatric drug-resistant epilepsy care

INTRODUCTION

Epilepsy affects millions of children worldwide, with 20-40% experiencing drug-resistant epilepsy (DRE) who are recommended for epilepsy surgery evaluation and may benefit from surgical management. However, many patients live with DRE for multiple years prior to surgical epilepsy referral or treatment or are never referred at all.

OBJECTIVE

We aimed to describe factors associated with referral for epilepsy surgery in the USA, in order to identify disparities in DRE, characterize why they may exist, and recognize areas for improvement.

METHODS

Pediatric patients diagnosed with DRE between January 1, 2004 and December 31, 2020 were identified from the Pediatric Health Information System (PHIS) Database. Patients treated with antiseizure medications (ASMs) only, ASMs plus vagus nerve stimulation (VNS), and ASMs plus cranial epilepsy surgery were studied regarding access to epilepsy surgery and disparities in care. This study used chi-square tests to determine associations between treatment time and preoperative factors. Preoperative factors studied included epilepsy treatment type, age, sex, race/ethnicity, insurance type, geographic region, patient type, epilepsy type, and presence of pediatric complex chronic conditions (PCCCs).

RESULTS

A total of 18,292 patients were identified; 10,240 treated with ASMs, 5019 treated with ASMs + VNS, and 3033 treated with ASMs + cranial epilepsy surgery. Sex was not found to significantly vary among groups. There was significant variation in age, census region, race/ethnicity, patient type, presence of PCCCs, diagnosis, and insurance (p < 0.001). Those treated surgically, either with VNS or cranial epilepsy surgery, were 2 years older than those medically treated. Additionally, those medically treated were less likely to be living in the Midwest (25.46%), identified as non-Hispanic white (51.78%), have a focal/partial epilepsy diagnosis (8.74%), and be privately insured (35.82%).

CONCLUSIONS

We studied a large administrative US database examining variables associated with surgical epilepsy evaluation and management. We found significant variation in treatment associated with age, US census region, race/ethnicity, patient type, presence of PCCCs, diagnosis, and health insurance type. We believe that these disparities in care are related to access and social determinants of health, and we encourage focused outreach strategies to mitigate these disparities to broaden access and improve outcomes in children in the USA with DRE.

Impact of Vagus Nerve Stimulation for the Treatment of Drug-Resistant Epilepsy on Patterns of Use and Cost of Health Care Services and Pharmacotherapy: Comparisons of the 24-Month Periods Before and After Implantation

PURPOSE

This study examines the impact of vagus nerve stimulation (VNS) as treatment for drug-resistant epilepsy (DRE) on the use and cost of health care services and pharmacotherapy.

METHODS

Using a large US health care claims database, we identified all patients with DRE who underwent VNS between January 1, 2012 and December 31, 2019. VNS implantation date was designated as the index date, and patients had to be continuously enrolled for the 24-month period before this date (preindex period). Outcomes included all-cause and epilepsy-related hospitalization, emergency department (ED) visits, and health care costs; health care claims resulting in an epilepsy diagnosis and all claims for antiseizure medications were deemed epilepsy related. Preindex data, except care related to preoperative medical clearance for VNS, were used to estimate multivariate regression models predicting outcomes during the 24-month postindex period (follow-up period). Predicted outcomes during follow-up were then compared with observed values. As a sensitivity analysis, we also replicated all analyses among subgroups defined by comorbid depression.

FINDINGS

A total of 659 patients underwent VNS for DRE and met the selection criteria. For the composite outcome of all-cause hospitalizations and ED visits, observed values were 42% lower than expected during the 24-month follow-up period; for the composite outcome of epilepsy-related hospitalizations and ED visits, observed values were 49% lower (P < 0.001 for both). Observed mean total all-cause costs, inclusive of costs of the procedure, were not significantly different than expected costs by month 19 of follow-up; mean total epilepsy-related costs were comparable by month 18. Findings were similar in subgroups with and without depression, although nominally greater differences (observed - expected) were seen in those with comorbid depression.

IMPLICATIONS

Our findings suggest that VNS is associated with decreased risk of hospitalization or ED visits (all cause and epilepsy related) during the 2-year period subsequent to implantation and may become cost-neutral within 2 years of implantation (vs continued medical management of DRE without VNS). Although expected outcomes were estimated based on the 24-month period before implantation, the degree to which they approximated what would have happened in the absence of VNS is unknowable. Further research is needed to better understand the extend and duration of the impact of VNS on seizure frequency and severity and health-related quality of life, including its performance among those with and without comorbid depression.

The association of multiple chronic conditions and healthcare expenditures among adults with epilepsy in the United States

RATIONALE

Epilepsy is a frequent neurologic condition with important financial strains on the US healthcare system. The co-occurrence of multiple chronic conditions (MCC) may have additional financial repercussions on this patient population. We aimed to assess the association of coexisting chronic conditions on healthcare expenditures among adult patients with epilepsy.

METHODS

We identified a total of 1,942,413 adults (≥18 years) with epilepsy using the clinical classification code 83 from the MEPS-HC (Medical Expenditure Panel Survey Household Component) database between 2003 and 2014. Chronic conditions were selected using the clinical classification system (ccs), and categorized into 0, 1, or 2 chronic conditions in addition to epilepsy. We computed unadjusted healthcare expenditures per year and per individual (total direct healthcare expenditure, inpatient expenditure, outpatient expenditure, prescription medication expenditure, emergency room visit expenditure, home healthcare expenditure and other) by number of chronic conditions. We applied a two-part model with probit (probability of zero vs non-zero cost) and generalized linear model (GLM) gamma family and log link (for cost greater than zero) to examine the independent association between chronic conditions, and annual expenditures per individual, generating incremental costs with 0 chronic condition as reference.

RESULTS

Over half of the patients with epilepsy had at least two chronic conditions (CC). Yearly, for each patient with one and two chronic conditions, unadjusted total healthcare expenditures were two times ($10,202; 95 %CI $6,551-13,853) to nearly three times ($21,277; 95 %CI $12,971-25,583) higher than those with no chronic conditions ($6,177; 95 %CI $4,895-7,459), respectively. In general healthcare expenditures increased with the number of chronic conditions for pre-specified cost categories. The incremental (adjusted) total healthcare expenditure increased with the number of chronic conditions (1CC vs 0 CC: $3,238; 95 %CI $524-5,851 p-value = 0.015 and ≥2 CC vs 0 CC: $8,145; 95 %CI $5,935-10,895 p-value < 0.001). In general, for all cost categories, incremental healthcare expenditures increased with the number of chronic conditions with the largest increment noted between those with 2 CC and those with 0 CC for inpatient ($2,025: 95 %CI $867-3,1830), outpatient ($2,141; 95 %CI $1,321-2,962), and medication ($1,852; 95 %CI $1,393-2,310).

CONCLUSION

Chronic conditions are frequent among adult patients with epilepsy and are associated with a dose-response increase in healthcare expenditure, a difference driven by inpatient, outpatient, and medication prescription expenditures. Greater coordination of epilepsy care accounting for the presence of multiple chronic conditions may help lower the cost of epilepsy.

Economic aspects of treating seizure clusters

Seizure clusters may initiate a chain of events that have economic as well as clinical consequences. The potential economic consequences of seizure clusters must be weighed against the cost of medication to attenuate them. This is true both for individual patients and for society. Data needed for economic analyses include the chance that a cluster will progress to an adverse outcome, such as a need for emergency care, the costs of such an outcome, the cost of a rescue medication (RM), and the effectiveness of the RM. Indirect costs, such as lost employment for patients and caregivers, must also be considered. Several types of economic analyses can be used to determine costs and benefits of a medical intervention. There are studies comparing different RMs from an economic perspective, but there is little direct information on the costs of using an RM versus allowing clusters to run their course. However, the high expense of consequences of seizure clusters makes it likely that effective RMs will make economic as well as medical sense for many patients.

Epilepsy in elderly patients: does age of onset make a difference?

INTRODUCTION

Epilepsy is most frequent in children and elderly people. Today's population is ageing and epilepsy prevalence is increasing. The type of epilepsy and its management change with age.

METHODS

We performed a retrospective, observational study comparing patients aged ≥ 65 years with epilepsy diagnosed before and after the age of 65, and describing epilepsy characteristics and comorbidities in each group.

RESULTS

The sample included 123 patients, of whom 61 were diagnosed at < 65 years of age (group A), 62 at ≥ 65 of age (group B). Sex distribution was similar in both groups, with 39 men (62.9%) in group A and 37 (60.7%) in group B. Mean age was 69.97 ± 5.6 years in group A and 77.29 ± 6.73 in group B. The most common aetiology was cryptogenic in group A (44.3%, n = 27) and vascular in group B (74.2%, n = 46). History of stroke was present in 12 patients from group A (19.7%) and 32 (51.6%) in group B. Antiepileptic drugs were prescribed at lower doses in group A. Statistically significant differences were found between groups for history of ischaemic stroke, cognitive impairment, psychiatric disorders, and diabetes mellitus; degree of dependence; and number of antiepileptic drugs.

CONCLUSION

Age of onset ≥ 65 years is closely related to cardiovascular risk factors; these patients require fewer antiepileptic drugs and respond to lower doses. Some cases initially present as status epilepticus.

Epilepsy in elderly patients: does age of onset make a difference?

INTRODUCTION

Epilepsy is most frequent in children and elderly people. Today's population is ageing and epilepsy prevalence is increasing. The type of epilepsy and its management change with age.

METHODS

We performed a retrospective, observational study comparing patients aged ≥ 65 years with epilepsy diagnosed before and after the age of 65, and describing epilepsy characteristics and comorbidities in each group.

RESULTS

The sample included 123 patients, of whom 61 were diagnosed at <65 years of age (group A), 62 at ≥ 65 of age (group B). Sex distribution was similar in both groups, with 39 men (62.9%) in group A and 37 (60.7%) in group B. Mean age was 69.97±5.6 years in group A and 77.29±6.73 in group B. The most common aetiology was unknown in group A (44.3%, n=27) and vascular in group B (74.2%, n=46). History of stroke was present in 12 patients from group A (19.7%) and 32 (51.6%) in group B. Antiepileptic drugs were prescribed at lower doses in group A. Statistically significant differences were found between groups for history of ischaemic stroke, cognitive impairment, psychiatric disorders, and diabetes mellitus; degree of dependence; and number of antiepileptic drugs.

CONCLUSION

Age of onset ≥ 65 years is closely related to cardiovascular risk factors; these patients require fewer antiepileptic drugs and respond to lower doses. Some cases initially present as status epilepticus.

Hospital costs associated with vagus nerve stimulation and medical treatment in pediatric patients with refractory epilepsy

Objectives

Refractory epilepsy is a diagnosis of recurrent seizures that requires multiple resources for optimal chronic management. The disease negatively impacts the lives of affected patients and families and poses an economic burden to the health care system. This study compares hospital costs between pediatric patients treated with antiseizure medications (ASMs) only and ASMs plus vagus nerve stimulation (VNS).

Methods

Patients 0–17 years of age who were diagnosed with refractory epilepsy between January 1, 2011 and December 31, 2016, were identified from the Children's Hospital Association's Pediatric Health Information System (PHIS) database. Patients treated with ASMs only or ASMs plus VNS were included in the study and were followed 1 year prior and 2 years after meeting pre‐determined criteria for refractory epilepsy. The difference‐in‐difference (DID) approach along with the two‐part model was used to compare the changes in mean hospital costs captured in the PHIS database over time between the two cohorts.

Results

One thousand one hundred thirteen patients treated with ASMs plus VNS and 3471 patients treated with ASMs only were included. At a follow‐up time of 2 years, for the ASMs‐only cohort, the adjusted all‐cause and epilepsy‐related mean annual total costs increased by $14 715 (95% confidence interval [CI]: $12 375–$17 055) and $18 437 (95% CI: $15 978–$20 896), respectively. By comparison, the adjusted all‐cause and epilepsy‐related mean annual total costs of the ASMs plus VNS cohort increased by $12 838 (95% CI: $8171–$17 505) and $15 183 (95% CI: $10 253–$20 113), respectively. Compared to ASMs only, ASMs plus VNS generated a cost savings of $3254 for epilepsy‐related annual costs per year after the index date.

Significance

Compared to ASMs alone, ASMs plus VNS is a treatment modality associated with lower annual hospital costs over time. Our study shows that VNS is a cost‐beneficial treatment for a national cohort of pediatric patients with refractory epilepsy.

Comparison of utilization and cost of healthcare services and pharmacotherapy following implantation of vagus nerve stimulation vs. responsive neurostimulation or deep brain stimulation for the treatment of drug-resistant epilepsy: analyses of a large United States healthcare claims database

AIM

Vagus nerve stimulation (VNS), responsive neurostimulation (RNS), and deep brain stimulation (DBS) all are options for drug-resistant epilepsy (DRE). However, little is known about how the choice of neurostimulation impacts subsequent healthcare costs.

MATERIALS AND METHODS

We used a large US healthcare claims database to identify all patients with epilepsy who underwent neurostimulation between 2012 and 2019. Eligible patients were identified and stratified based on procedure received (VNS vs. RNS/DBS). VNS patients were matched by propensity scoring to RNS/DBS patients. Use and cost of healthcare resources and pharmacotherapy were ascertained over the 24-month period following neurostimulation, incorporating all-cause and epilepsy-related measures. Disease-related care was defined based on diagnoses of claims for medical care and relevant pharmacotherapies.

RESULTS

Seven hundred and ninety-two patients met all selection criteria. VNS patients were younger, were prescribed a higher pre-index mean number of anti-seizure medications (ASMs), and had higher pre-index levels of use and cost of epilepsy-related healthcare services. We propensity matched 148 VNS patients to an equal number of RNS/DBS patients. One year following index date (inclusive), mean total all-cause healthcare costs were 50% lower among VNS patients than RNS/DBS patients, and mean epilepsy-related costs were 55% lower; corresponding decreases at the two-year mark were 41% and 48%, respectively.

LIMITATIONS

Some clinical variables, such as seizure frequency and severity, quality of life, and functional status were unavailable in the database, precluding our ability to comprehensively assess differences between devices. Administrative claims data are subject to billing code errors, inaccuracies, and missing data, resulting in possible misclassification and/or unmeasured confounding.

CONCLUSIONS

After matching, VNS was associated with significantly lower all-cause and epilepsy-related costs for the two-year period following implantation. All-cause and epilepsy-related costs remained statistically significantly lower for VNS even after costs of implantation were excluded.

The use of virtual tools in narrowing the impact of health disparities in neurology

The concept of Epilepsy Treatment Gap (ETG) refers to the proportion of people with epilepsy who are not being appropriately treated. The ETG in the USA approaches 10%, with historically underserved populations and rural populations disproportionately affected. The ETG in Low-and Middle-Income Countries (LMIC) is reported to be 5-10 times higher than in high-income countries. The growing availability of reliable internet access offers a unique opportunity to provide better care to children and adults with epilepsy. In this paper we explore various telehealth (TH) initiatives that have leveraged the availability of easy and free access to an internet connection in reducing the ETG in underserved regions of the world. We describe several interventions targeted to reach patients and providers in rural areas of the United States and in LMIC. First, we examine initiatives that were developed to improve patient access to coordinated care and education regarding epilepsy and seizures. Next, we describe an intervention designed to improve knowledge of epilepsy diagnosis and treatment for providers in LMIC. We conclude with a brief overview of the use of virtual tools in diminishing the ETG.

Secular Trends in the Incidence, Prevalence, and Medications for Epilepsy from 2007 to 2015 in Taiwan: A Nationwide Population-Based Study

BACKGROUND

Patients with epilepsy have a higher mortality rate than the general population. Up-to-date estimates of epilepsy incidence, prevalence, and medication use are critical to assist policymaking.

METHODS

Using the National Taiwan Insurance Research Database, the standardized incidence and prevalence of epilepsy were estimated in each calendar year from 2007 to 2015. We used the incident cases of epilepsy to analyze the change in prescribing patterns from 2007 to 2015. Joinpoint regression was used to estimate secular trends.

RESULTS

From 2007 to 2015, the age- and sex-standardized incidence decreased from 0.72 (95% confidence interval [CI] 0.70-0.73) to 0.54 (95% CI 0.53-0.55) per 1,000 person-years, giving an annual percentage change (APC) of -2.73 (p < 0.05). Among patients younger than 20 years, the incidence did not change significantly. The age- and sex-standardized prevalence decreased from 6.94 (95% CI 6.90-6.98) to 6.86 (95% CI, 6.82-6.89) per 1,000 people, giving an APC of -0.31 (p < 0.05). However, the prevalence increased in the 35- to 49- and 50- to 64-year age-groups. The most common first-line anticonvulsant was phenytoin in 2007 and valproate in 2015. The use of levetiracetam, clobazam, and valproate increased during the study period, with APCs of 25.48% (95% CI 19.97-31.24), 6.41 (3.09-9.85), and 2.83 (1.51-4.16), respectively. The use of carbamazepine, phenytoin, and topiramate decreased; the APCs were -23.86% (95% CI -25.25 to -22.44), -6.61 (-8.40 to -4.79), and -4.29% (-7.87 to -0.57), respectively.

CONCLUSIONS

The overall prevalence and incidence of epilepsy decreased slightly from 2007 to 2015. The prescribed first-line anticonvulsant also changed over time.

Comparison of healthcare resource utilization in pediatric patients with refractory epilepsy: Vagus nerve stimulation and medical treatment cohorts

OBJECTIVES

Refractory epilepsy imposes a substantial burden on affected patients, families, and healthcare system. In terms of treating seizures in children, vagus nerve stimulation (VNS) has been proved to be comparable to that of antiepileptic drugs (AEDs). This study compared healthcare resource utilization between pediatric patients treated with AEDs only and AEDs plus VNS.

METHODS

Pediatric patients diagnosed with refractory epilepsy between the 1st of January 2011 and the 31st of December 2016 were identified from the Pediatric Health Information System Database. Patients treated with AEDs only or AEDs plus VNS were included in the study and were followed up from one year before to two years after the date when defined criteria for refractory epilepsy were met. The difference-in-difference approach along with the hurdle model was used to compare the changes in healthcare resource utilization over time between patients treated with AEDs only and AEDs plus VNS.

RESULTS

The study included 1502 patients treated with AEDs plus VNS and 4541 patients treated with AEDs only. There was a difference in post-index all-cause and epilepsy-related inpatient visits compared to the pre-index period: inpatient hospitalizations were decreased in the AEDs plus VNS cohort, and increased in the AEDs only cohort. There was no significant difference in the pre-index to post-index change for all-cause and epilepsy-related emergency department visits between the two treatment cohorts. For outpatient encounters in the initial post-index period, patients treated with AEDs plus VNS had significantly higher increase in all-cause and epilepsy-related outpatient visits compared to the AEDs only cohort.

CONCLUSIONS

Compared to those treated with AEDs only, pediatric patients with refractory epilepsy treated with AEDs plus VNS have fewer inpatient visits and more outpatient visits within a 2-year follow-up. Given the lower acuity of care in outpatient versus inpatient settings, this study can inform treatment choices for children with refractory epilepsy.

Persistent racial and ethnic disparities as a potential source of epilepsy surgery underutilization: Analysis of large national datasets from 2006-2016

OBJECTIVE

High volume surgical epilepsy centers have reported a decrease in surgical resections and an increase in intracranial monitoring. Despite this increase in complexity, epilepsy surgery remains significantly underutilized. The goal of this study is to examine the utilization of and access to epilepsy surgery in the United States from 2006 to 2016.

METHODS

We used administrative datasets from the National Inpatient Sample (NIS) and Center for Medicare and Medicaid Services (CMS) to report national estimates of epilepsy surgery and changes in surgery types. We also examined disparities and barriers in access to epilepsy surgery.

RESULTS

Inpatient epilepsy admissions increased from 2.41 to 5.78 per 100,000 between 2006 and 2016, while surgical epilepsy admissions plateaued after 2011. Open resections comprised 75 % of all surgical cases from 2006 to 2011 then decreased each year to 50 % in 2016 with both temporal and extratemporal resections decreasing proportionally. Intracranial monitoring increased in the last two years of the study due to an increase in SEEG/depth electrode cases. The multivariate analysis showed that patients with Medicaid (OR 0.75, 95 % CI 0.67-0.83) and Medicare (OR 0.62, 95 % CI 0.54-0.70) were significantly less likely to undergo epilepsy surgery compared to those with private insurance. Black patients were less likely to undergo epilepsy surgery than White or Hispanic patients (OR 0.57, 95 % CI 0.49-0.67). No significant difference was found in epilepsy surgery rates after implementation of the Affordable Care Act (ACA) in 2014.

CONCLUSION

This study identifies recent trends in epilepsy surgical approaches and suggests that improving access to care does not necessarily address disparities present in the treatment of epilepsy patients who need surgical care.

Impact of Mesial Temporal Lobe Resection on Brain Structure in Medically Refractory Epilepsy

OBJECTIVE

Surgical resection can decrease seizure frequency in medically intractable temporal lobe epilepsy. However, the functional and structural consequences of this intervention on brain circuitry are poorly understood. We investigated structural changes that occur in brain circuits after mesial temporal lobe resection for refractory epilepsy. Specifically, we used neuroimaging techniques to evaluate changes in 1) contralesional hippocampal and bilateral mammillary body volume and 2) brain-wide cortical thickness.

METHODS

Serial T1-weighted brain magnetic resonance images were acquired before and after surgery (1.6 ± 0.5 year interval) in 21 patients with temporal lobe epilepsy (9 women, 12 men; mean age, 39.4 ± 11.5 years) who had undergone unilateral temporal lobe resection (14 anterior temporal lobectomy; 7 selective amygdalohippocampectomy). Blinded manual segmentation of the unresected hippocampal formation and bilateral mammillary bodies was performed using the Pruessner and Copenhaver protocols, respectively. Brain-wide cortical thickness estimates were computed using the CIVET pipeline.

RESULTS

Surgical resection was associated with a 5% reduction in contralesional hippocampal volume (P < 0.01) and a 9.5% reduction in mammillary body volume (P = 0.03). In addition, significant changes in cortical thickness were observed in contralesional anterior and middle cingulate gyrus and insula (P_{false discovery rate} < 0.01) as well as in other temporal, frontal, and occipital regions (P_{false discovery rate} < 0.05). Postoperative verbal memory function was significantly associated with cortical thickness change in contralesional inferior temporal gyrus (R² = 0.39; P = 0.03).

CONCLUSIONS

These results indicate that mesial temporal lobe resection is associated with both volume loss in spared Papez circuitry and changes in cortical thickness across the brain.

Spontaneous seizures and elevated seizure susceptibility in response to somatic mutation of sodium channel Scn8a in the mouse

De novo mutations of neuronal sodium channels are responsible for ~5% of developmental and epileptic encephalopathies, but the role of somatic mutation of these genes in adult-onset epilepsy is not known. We evaluated the role of post-zygotic somatic mutation by adult activation of a conditional allele of the pathogenic variant Scn8aR1872W in the mouse. After activation of CAG-Cre-ER by tamoxifen, the mutant transcript was expressed throughout the brain at a level proportional to tamoxifen dose. The threshold for generation of spontaneous seizures was reached when the proportion of mutant transcript reached 8% of total Scn8a transcript, equivalent to expression of the epileptogenic variant in 16% of heterozygous neurons. Expression below this level did not result in spontaneous seizures, but did increase susceptibility to seizure induction by kainate or auditory stimulation. The relatively high threshold for spontaneous seizures indicates that somatic mutation of sodium channels is unlikely to contribute to the elevated incidence of epilepsy in the elderly population. However, somatic mutation could increase susceptibility to other seizure stimuli.

Primary payer status in patients with seizures: A nationwide study during 1997-2014 in the United States

OBJECTIVE

In countries where health coverage is not universal, there is ample evidence of disparities in healthcare, often associated with insurance. People with seizures, similar to those living with any complicated chronic medical comorbidity, need further health-related attention to improve their quality-of-life outcomes.

METHODS

We conducted a retrospective cohort study of the National Inpatient Sample (NIS) component of the Healthcare Cost and Utilization Project (HCUP) national database between 1997-2014. The analysis focused on the mortality rate, and patients with a principal admission diagnosis of seizure at the time of discharge were identified. Primary Payer Status (PPS) included Medicare, Medicaid, private, and uninsured. Multivariate linear regression modeling was conducted to examine the contribution of the predictive variables to in-hospital mortality.

RESULTS

Between 1997-2014, 4,594,213 seizure-related discharges was recorded. The overall mean patient age was 41.69 ± 0.98 years, and 58.1 % were female. The average age during this period decreased significantly in Medicare, increased substantially in uninsured, without significant change in Medicaid and private. Patients in Medicare had the highest length of stay (LOS) (4.49 ± 0.29 days), and uninsured (2.79 ± 0.15) had the least. Over time, there was a significant increase in the number of seizure discharges in Medicare, Medicaid, and private insurance. However, there was a significant decrease in in-hospital mortality in Medicare, Medicaid, and private, with the most prominent decline in Medicare. Risk-adjusted for age, gender, LOS, illness severity, and time, regression results showed Medicare has a significantly higher association with less in-hospital mortality compared with other insurances.

CONCLUSIONS

Our study showed a significant increase in the number of seizure diagnoses at discharge in Medicare, Medicaid, and private in the United States between 1997-2014; however, there was a decrease in the in-hospital mortality rate across all insurance payers. Uninsured patients had the highest mortality rate after Medicare without risk justification. Risk-stratified models confirmed Medicare was significantly associated with a less in-hospital mortality rate.

THE IMPACT OF ANTIEPILEPTIC TREATMENT IN PREGNANCY ON PERINATAL OUTCOME IN CROATIA - A SINGLE-CENTER STUDY

Pregnancy can alter the natural course of epilepsy and affect pharmacokinetic profile of antiepileptic drugs (AEDs) making therapeutic management more demanding. Since there is no relevant population-based study in Croatia to date, we conducted this research with the aim to observe antiepileptic treatment policy in pregnancy and to determine if the number of AEDs affects pregnancy outcomes. The study included all women with epilepsy with singleton pregnancy exposed to one or more AEDs divided into two groups (group 1: one AED and group 2: more than one AED used). Data were collected retrospectively at the Department of Obstetrics and Gynecology, Zagreb University Hospital Centre, Zagreb, Croatia, and included 153 women from January 2010 to December 2018. Primary outcomes included rates of preterm delivery, major fetal malformations, gestational hypertension, cesarean section rate, and appearance of seizures during pregnancy. We found higher rates of all pregnancy complications examined than in the general population, while comparison of the two study groups yielded significant differences. Preterm labor was detected in 30% of deliveries in polytherapy group compared to 16.6% in monotherapy group (p=0.03). Gestational hypertension was recorded in 20% of women in polytherapy group vs. 4.90% in monotherapy group (p=0.009). There was also a high rate of cesarean deliveries in polytherapy group (27.5%). Seizures during pregnancy occurred in 48.4% of patients in polytherapy group, which was significantly higher than the rate recorded in monotherapy group (p=0.015). In this single-center retrospective study, women with epilepsy using AEDs during pregnancy had a higher rate of gestational hypertension and preterm delivery than the general population of pregnant women. To the best of our knowledge, this is the first study in Croatia observing antiepileptic treatment policy in pregnancy with regards to AED regimen and perinatal outcome.

Paternal exposure to antiepileptic drugs and offspring outcomes: a nationwide population-based cohort study in Sweden

OBJECTIVES

To investigate the association between paternal use of antiepileptic drugs (AEDs) and adverse neurodevelopmental outcomes and major congenital malformations (MCM) in the offspring.

METHODS

Using nationwide Swedish registries, we included 1 144 795 births to 741 726 fathers without epilepsy and 4544 births to 2955 fathers with epilepsy. Of these, 2087 (45.9%) were born to fathers with epilepsy who had dispensed an AED during the conception period. Children who had both parents with epilepsy were excluded. The incidence rate of MCM, autism spectrum disorder, attention deficit hyperactivity disorder (ADHD) and intellectual disability in offspring was analysed.

RESULTS

Offspring of fathers exposed to AEDs did not show an increased risk of MCM (adjusted OR 0.9, 95% CI 0.7 to 1.2), autism (adjusted HR (aHR) 0.9, 95% CI 0.5 to 1.7), ADHD (aHR 1.1, 95% CI 0.7 to 1.9) or intellectual disability (aHR 1.3, 95% CI 0.6 to 2.8) compared with offspring of fathers with epilepsy not exposed to AEDs. Among offspring of fathers with epilepsy who used valproate in monotherapy during conception, rates of autism (2.9/1000 child-years) and intellectual disability (1.4/1000 child-years) were slightly higher compared with the offspring of fathers with epilepsy who did not use AEDs during conception (2.1/1000 child-years autism, 0.9/1000 child-years intellectual disability), but in the propensity-score adjusted analyses, no statistically significant increased risk of adverse outcomes was found.

CONCLUSIONS

Paternal AED use during conception is not associated with adverse outcomes in the offspring.

The Effectiveness of Medical and Surgical Treatment for Children With Refractory Epilepsy

BACKGROUND

Pediatric refractory epilepsy affects quality of life, clinical disability, and healthcare costs for patients and families.

OBJECTIVE

To show the impact of surgical treatment for pediatric epilepsy on healthcare utilization compared to medically treated pediatric epilepsy over 5 yr.

METHODS

The Pediatric Health Information System database was used to conduct a cohort study using 5 published algorithms. Refractory epilepsy patients treated with antiepileptic medications (AEDs) only or AEDs plus epilepsy surgery between 1/1/2008 and 12/31/2014 were included. Healthcare utilization following the index date at 2 and 5 yr including inpatient, emergency department (ED), and all epilepsy-related visits were evaluated. The propensity scores (PS) method was used to match surgically and medically treated patients. PS. SAS® 9.4 and Stata 14.0 were used for data management and statistical analysis.

RESULTS

A total of 2106 (17.1%) and 10186 (82.9%) were surgically and medically treated. A total of 4050 matched cases, 2025 per each treated group, were included. Compared to medically treated patients, utilization was reduced in the surgical group: at 2 and 5 yr postindex date, there was a reduction of 36% to 37% of inpatient visits and 47% to 50% of ED visits. The total number (inpatient, ED, ambulatory visits) of epilepsy-associated visits were reduced by 39% to 43% in the surgical group compared to the medically treated group. In those who had surgery, the average reduction in AEDs was 16% at 2 and 5 yr after treatment.

CONCLUSION

Patients with refractory epilepsy treated with surgery had significant reductions in healthcare utilization compared with patients treated only with medications.

Accuracy of ICD-10-CM claims-based definitions for epilepsy and seizure type

OBJECTIVE

To evaluate the accuracy of ICD-10-CM claims-based definitions for epilepsy and classifying seizure types in the outpatient setting.

METHODS

We reviewed electronic health records (EHR) for a cohort of adults aged 18+ years seen by six neurologists who had an outpatient visit at a level 4 epilepsy center between 01/2019-09/2019. The neurologists used a standardized documentation template to capture the diagnosis of epilepsy (yes/no/unsure), seizure type (focal/generalized/unknown), and seizure frequency in the EHR. Using linked ICD-10-CM codes assigned by the provider, we assessed the accuracy of claims-based definitions for epilepsy, focal seizure type, and generalized seizure type against the reference-standard EHR documentation by estimating sensitivity (Sn), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

There were 673 eligible outpatient encounters. After review of EHRs for standardized documentation, an analytic sample consisted of 520 encounters representing 402 unique patients. In the EHR documentation, 93.5 % (n = 486/520) of encounters were with patients with a diagnosis of epilepsy. Of those, 66.0 % (n = 321/486) had ≥1 focal seizure, 41.6 % (n = 202/486) had ≥1 generalized seizure, and 7% (n = 34/486) had ≥1 unknown seizure. An ICD-10-CM definition for epilepsy (i.e., ICD-10 G40.X) achieved Sn = 84.4 % (95 % CI 80.8-87.5%), Sp = 79.4 % (95 % CI 62.1-91.3%), PPV = 98.3 % (95 % CI 96.6-99.3%), and NPV = 26.2 % (95 % CI 18.0-35.8%). The classification of focal vs generalized/unknown seizures achieved Sn = 69.8 % (95 % CI 64.4-74.8%), Sp = 79.4 % (95 % CI 72.4-85.3%), PPV = 86.8 % (95 % CI 82.1-90.7%), and NPV = 57.5 % (95 % CI 50.8-64.0%).

CONCLUSIONS

Claims-based definitions using groups of ICD-10-CM codes assigned by neurologists in routine outpatient clinic visits at a level 4 epilepsy center performed well in discriminating between patients with and without a diagnosis of epilepsy and between seizure types.

Antiepileptic Drug Treatment Patterns in Women of Childbearing Age With Epilepsy

Importance

Limited population-based data are available on antiepileptic drug (AED) treatment patterns in women of childbearing age with epilepsy; the current population risk is not clear.

Objectives

To examine the AED treatment patterns and identify differences in use of valproate sodium and topiramate by comorbidities among women of childbearing age with epilepsy.

Design, Setting, and Participants

A retrospective cohort study used a nationwide commercial database and supplemental Medicare as well as Medicaid insurance claims data to identify 46 767 women with epilepsy aged 15 to 44 years. The eligible study cohort was enrolled between January 1, 2009, and December 31, 2013. Data analysis was conducted from January 1, 2017, to February 22, 2018.

Exposures

Cases required an International Classification of Diseases, Ninth Revision, Clinical Modification-coded epilepsy diagnosis with continuous medical and pharmacy enrollment. Incident cases required a baseline of 2 or more years without an epilepsy diagnosis or AED prescription before the index date. For both incident and prevalent cases, focal and generalized epilepsy cohorts were matched by age, payer type, and enrollment period and then compared.

Main Outcomes and Measures

Antiepileptic drug treatment pattern according to seizure type and comorbidities.

Results

Of the 46 767 patients identified, there were 8003 incident cases (mean [SD] age, 27.3 [9.4] years) and 38 764 prevalent cases (mean [SD] age, 29.7 [9.0] years). Among 3219 women in the incident epilepsy group who received AEDs for 90 days or more, 3173 (98.6%) received monotherapy as first-line treatment; among 28 239 treated prevalent cases, 18 987 (67.2%) received monotherapy. In 3544 (44.3%) incident cases and 9480 (24.5%) prevalent cases, AED treatment was not documented during 180 days or more of follow-up after diagnosis. Valproate (incident: 35 [5.81%]; prevalent: 514 [13.1%]) and phenytoin (incident: 33 [5.48%]; prevalent: 178 [4.53%]) were more commonly used for generalized epilepsy and oxcarbazepine (incident: 53 [8.03%]; prevalent: 386 [9.89%]) was more often used for focal epilepsy. Levetiracetam (incident: focal, 267 [40.5%]; generalized, 271 [45.0%]; prevalent: focal, 794 [20.3%]; generalized, 871 [22.2%]), lamotrigine (incident: focal, 123 [18.6%]; generalized, 106 [17.6%]; prevalent: focal, 968 [24.8%]; generalized, 871 [22.2%]), and topiramate (incident: focal, 102 [15.5%]; generalized, 64 [10.6%]; prevalent: focal, 499 [12.8%]; generalized, 470 [12.0%]) were leading AEDs prescribed for both focal and generalized epilepsy. Valproate was more commonly prescribed for women with comorbid headache or migraine (incident: 53 of 1251 [4.2%]; prevalent: 839 of 8046 [10.4%]), mood disorder (incident: 63 of 860 [7.3%]; prevalent: 1110 of 6995 [15.9%]), and anxiety and dissociative disorders (incident: 57 of 881 [6.5%]; prevalent: 798 of 5912 [13.5%]). Topiramate was more likely prescribed for those with comorbid headache or migraine (incident: 335 of 1251 [26.8%]; prevalent: 2322 of 8046 [28.9%]).

Conclusions and Relevance

Many women appear to be treated with valproate and topiramate despite known teratogenicity risks. Comorbidities may affect selecting certain AEDs despite their teratogenicity risks.

Patterns of seizure prophylaxis after oncologic neurosurgery

BACKGROUND

Evidence supporting routine postoperative antiepileptic drug (AED) prophylaxis following oncologic neurosurgery is limited, and actual practice patterns are largely unknown beyond survey data.

OBJECTIVE

To describe patterns and predictors of postoperative AED prophylaxis following intracranial tumor surgery.

METHODS

The MarketScan Database was used to analyze pharmacy claims data and clinical characteristics in a national sample over a 5-year period.

RESULTS

Among 5895 patients in the cohort, levetiracetam was the most widely used AED for prophylaxis (78.5%) followed by phenytoin (20.5%). Prophylaxis was common but highly variable for patients who underwent open resection of supratentorial intraparenchymal tumors (62.5%, reference) or meningiomas (61.9%). In multivariate analysis, biopsies were less likely to receive prophylaxis (44.8%, OR 0.47, 95% CI 0.33-0.67), and there was near consensus against prophylaxis for infratentorial (9.7%, OR 0.07, CI 0.05-0.09) and transsphenoidal procedures (0.4%, OR 0.003, CI 0.001-0.010). Primary malignancies (52.1%, reference) and secondary metastases (42.2%) were more likely to receive prophylaxis than benign tumors (23.0%, OR 0.63, CI 0.48-0.83), as were patients discharged with home services and patients in the Northeast. There was a large spike in duration of AED use at approximately 30 days.

CONCLUSIONS

Use of seizure prophylaxis following intracranial biopsies and supratentorial resections is highly variable, consistent with a lack of guidelines or consensus. Current practice patterns do not support a clear standard of care and may be driven in part by geographic variation, availability of post-discharge services, and electronic prescribing defaults rather than evidence. Given uncertainty regarding effectiveness, indications, and appropriate duration of AED prophylaxis, well-powered trials are needed.

Refractory epilepsy and nonadherence to drug treatment

In patients with epilepsy, nonadherence to agreed antiepileptic drug (AED) treatment may result in seizure relapse, and at worst sudden unexpected death. The aim of this study was to examine the extent of both unintentional and intentional nonadherence among Norwegian patients with refractory epilepsy and try to identify possible risk factors. At the National Centre for Epilepsy in Norway, 333 consecutive adult in- and outpatients with refractory epilepsy participated in an anonymous survey about adherence to drug treatment. Twenty-two percentages admitted that they sometimes or often forgot to take their drugs as scheduled, and 19% reported that they, rarely, sometimes or often intentionally did not follow the AED treatment plan agreed upon with their physician. Young age and depression were significantly correlated with unintentional nonadherence. Intentional nonadherence was associated with young age (36 years or younger). We found nonadherence not to be associated with any specific AED. In conclusion, about one-fifth of patients with refractory epilepsy admitted that they did not adhere to the agreed drug treatment plan, either intentionally or unintentionally. Measures to reduce nonadherence in this patient group may improve seizure control and should be tailored to address both unintentional and intentional lack of adherence.

New-onset lesional and nonlesional epilepsy in the US population: Patient characteristics and patterns of antiepileptic drug use

PURPOSE

Describe treatment patterns in patients from the United States with new-onset epilepsy, comparing those with and without lesional epilepsy.

METHODS

In this observational study we used Truven Health MarketScan databases derived from commercial health insurance, Medicare and Medicaid claims covering at least 5 years, commencing in 2008. We identified incident epilepsy cases based on International Classification of Diseases, Ninth Revision, Clinical Modification codes indicating epilepsy or recurrent seizures, taking into account antiepileptic drug (AED) claims, consistent with International League Against Epilepsy Commission on Epidemiology recommendations. We identified patients with lesional epilepsy when associated diagnoses indicated central nervous system infection, neoplasm, traumatic brain injury, stroke, senile dementia and static encephalopathy. Lesional and nonlesional cohorts were matched 1:1 on baseline characteristics of age, sex and insurance type for group comparisons.

RESULTS

In unmatched cohorts lesional epilepsy patients (N = 15,302) were more commonly older (mean age 48.7 years) compared with nonlesional epilepsy patients (N = 15,970; mean age 18.5 years). Among lesional patients <20 years of age, the leading putative etiology was static encephalopathy, while among ages ≥20 years and older, the leading putative etiology was stroke or cerebrovascular disease. In matched cohorts (7063 patients each), those with lesional epilepsy were significantly less likely to be untreated at 1 year versus those with nonlesional epilepsy (37.2% vs 56.1%). In children and adults among matched cohorts, levetiracetam was the most common AED prescribed for initial AED therapy for the lesional (39.5%) and nonlesional (32.1%) groups. Lesional epilepsy patients on monotherapy were only slightly less likely than nonlesional epilepsy patients to be on the same AED 1 year after treatment initiation (55.6% vs 59.7%).

SIGNIFICANCE

Compared with patients with lesional epilepsy, a higher proportion of patients with nonlesional epilepsy remain untreated 1 year after diagnosis. There were differences in AED selection by epilepsy etiology; levetiracetam is the most commonly prescribed drug for both cohorts.

Health literacy and quality of life in patients with treatment-resistant epilepsy

This exploratory study examined the impact of health literacy on quality of life (QoL) in patients with treatment-resistant epilepsy (TRE). Health literacy is a discrete form of literacy in which an individual can readily interpret prose and apply that skill to understand medical, pharmaceutical, and self-management information. From the perspectives of cultural health capital (CHC) and social disability theory, we hypothesized that greater levels of health literacy would be associated with a higher QoL score. The sample (n = 79) included adult patients with TRE enrolled in the University of Alabama at Birmingham Cannabidiol Program. The data were analyzed by using nested linear regression. Respondents aged 19-63 years (mean, standard deviation [SD] = 32.9 [13.65]) and were 92% white; 44% of patients were in Special Education until age 21 years, and 29% reported a total annual family income of less than $25,000. Significant bivariate relationships were found between health literacy and QoL (p = .004), age (p = .0001), and income (p = .036). There was a significant difference in health literacy scores for patients who completed high school or less (mean [SD] = 0.68 [0.86]) and those with any postsecondary education (mean [SD] = 1.59 [1.0]). The regression results showed health literacy to be positively associated with QoL where a 1% increase in health literacy was associated with a 6.61-point increase in QoL (p = .004), and this pattern persisted through each addition of other independent factors and control variables. This is one of the first studies investigating the role of health literacy in QoL among patients with TRE. The results suggest that health literacy is important and may function as a tool through which healthcare participation is expanded. Further research is needed with larger, more diverse, and longitudinal samples to accurately model the development of health literacy and its impact on QoL in this population.

National declines in the percentages of uninsured among adults aged 18-64 years with active epilepsy, 2010 and 2013 to 2015 and 2017-U.S. National Health Interview Survey

Epilepsy is more common among children and adults living in households at lowest incomes. Like those living with any complex chronic condition, people with epilepsy need quality healthcare to improve their health and social outcomes. The purpose of this study was to use the latest national data to provide updated estimates of the percentages of adults aged 18-64 years with active epilepsy who were uninsured in 2010, 2013, 2015, and 2017 and to examine changes in health insurance coverage during these years. We analyzed nationally representative samples of adults (aged 18-64 years) from the 2010, 2013, 2015, and 2017 National Health Interview Survey (NHIS). We used a validated epilepsy surveillance case definition to classify adults as having active epilepsy during 2010 and 2013 (n = 507) and during 2015 and 2017 (n = 582). We used the NHIS recode variables available in each year that account for a series of questions posed to respondents to confirm coverage and that ultimately classify respondents with different healthcare coverage types. Overall, the percentage of uninsured adults among respondents aged 18-64 years with active epilepsy decreased by more than half (59%), from 17.7% (95% confidence interval [CI] = 13.6%-22.7%) in 2010 and 2013 to 7.3% (95% CI = 4.8%-10.7%) in 2015 and 2017. The decrease in the percentage of uninsured adults with active epilepsy after 2010 and 2013 was balanced by a similar increase in public insurance coverage and private insurance coverage in 2015 and 2017. Epilepsy stakeholders can ensure that all uninsured adults with epilepsy obtain access to health insurance coverage. National Health Interview Survey data on epilepsy, when available, can be used to monitor trends in insurance status in the new decade.

Genomic testing in pediatric epilepsy

Genomic testing has become routine in the diagnosis and management of pediatric patients with epilepsy. In a single test, hundreds to thousands of genes are examined for DNA changes that may not only explain the etiology of the patient's condition but may also inform management and seizure control. Clinical genomic testing has been in clinical practice for less than a decade, and because of this short period of time, the appropriate clinical use and interpretation of genomic testing is still evolving. Compared to the previous era of single-gene testing in epilepsy, which yielded a diagnosis in <5% of cases, many clinical genomic studies of epilepsy have demonstrated a clinically significant diagnosis in 30% or more of patients tested. This review will examine key studies of the past decade and indicate the clinical scenarios in which genomic testing should be considered standard of care.

Challenges in epilepsy-The perspective of Norwegian epilepsy patients

OBJECTIVES

For most people with epilepsy (PWE), problems that are not directly related to seizures may constitute major challenges in everyday life. The purpose of this study was to determine the extent of these challenges and any risk factors for their occurrence among PWE in Norway, based on the patients' own perspective.

MATERIALS AND METHODS

We used a web-based survey to ask PWE visiting the homepage of the Norwegian Epilepsy Association about different everyday challenges. A link to the survey was accessible via the members' homepage for a 4-month period during 2017.

RESULTS

One thousand one hundred eighty-two PWE responded to the questionnaire. Although more than 40% of the cohort reported that they had been seizure free for at least 1 year, the majority reported that tiredness (71%), memory problems (70%), concentration problems (68%), headache or vertigo (51%), and feeling depressed (59%) continued to represent challenges. In addition, fear of being alone, sexual problems or difficulties in social settings were reported by about one-third of the patients. Reporting having these challenges was significantly associated with female gender, polytherapy, experiencing seizures during the previous 12 months and feeling blue or depressed.

CONCLUSIONS

The results of this study, reflecting a self-selected Norwegian population, provide insights into the challenges not directly associated with seizures that impact on the quality of life of PWE. The impacts of such challenges may be underestimated as components of the entire burden of epilepsy.

Using EHRs to advance epilepsy care

The improved use of Electronic Health Record (EHR) Systems provides an opportunity to improve the overall efficiency and quality of care of patients with epilepsy. Tools and strategies that may be incorporated into the use of EHRs include utilizing patient generated data, clinical decision support systems and natural language processing systems. Standardization of data from EHR systems may lead to improvement in clinical research through the creation of data collections and multi-center collaborations. Challenges to collaborative use of EHR Systems across centers include costs and the diversity of EHR systems.

Insurance transitions and healthcare utilization for children with refractory epilepsy

OBJECTIVES

The objective of the study is to investigate the association between insurance transitions and healthcare utilization among children with refractory epilepsy.

METHODS

We applied published algorithms to identify the study cohort of children with a diagnosis of refractory epilepsy who were treated between 10/1/2013 and 9/30/2014 at 36 children's hospitals in the United States. Insurance transition was defined as having any change in the type of primary payer from the first date of diagnosis to the date of the last visit at the same hospital. Univariate and multilevel multivariable analytical methods were used in the study.

RESULTS

Among 3488 children hospitalized with refractory epilepsy, rates of insurance transitions at 1, 2, and 5 years of refractory epilepsy diagnosis were 8.1%, 14%, and 29.9%, respectively. Patients whose primary payer at diagnosis was Private or Others were more likely to experience insurance transitions than patients whose primary payer was Medicaid. Younger children were associated with a higher risk of insurance transitions than older children. The high intensity of insurance transitions was associated with a higher number of emergency department and inpatient visits.

CONCLUSIONS

Insurance transitions interrupted the continuity of medical care for children with refractory epilepsy and were associated with more frequent hospitalizations and emergency department visits, which then translated to higher healthcare costs. Medicaid provided stable insurance coverage and is critically important for these patients and should be the main focus for policies aiming to minimize insurance transitions and optimize healthcare delivery.

Epidemiology of traumatic brain injury-associated epilepsy and early use of anti-epilepsy drugs: An analysis of insurance claims data, 2004-2014

BACKGROUND

About 2.8 million TBI-related emergency department visits, hospitalizations and deaths occurred in 2013 in the United States. Post-traumatic epilepsy (PTE) can be a disabling, life-long outcome of TBI.

OBJECTIVES

The purpose of this study is to address the probability of developing PTE within 9 years after TBI, the risk factors associated with PTE, the prevalence of anti-epileptic drug (AEDs) use, and the effectiveness of using AEDs prophylactically after TBI to prevent the development of PTE.

METHODS

Using MarketScan® databases covering commercial, Medicare Supplemental, and multi-state Medicaid enrollees from 2004 to 2014, we examined the incidence of early seizures (within seven days after TBI) and cumulative incidence of PTE, the hazard ratios (HR) of PTE by age, gender, TBI severity, early seizure and AED use (carbamazepine, clonazepam, divalproex sodium, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, phenytoin, pregabalin, topiramate, acetazolamide). We used backward selection to build the final Cox proportional hazard model and conducted multivariable survival analysis to obtain estimates of crude and adjusted HR (cHRs, aHRs) of PTE and 95% confidence intervals (CI).

RESULTS

The incidence of early seizure among TBI patients in our study was 0.5%. The cumulative incidence of PTE increased from 1.0% in one year to 4.0% in nine years. Most patients with TBI (93%) were not prescribed any AED. Gender was not associated with PTE. The risk of PTE was higher for individuals with older age, early seizures, and more severe TBI. Only individuals using prophylactic acetazolamide had significantly lower risk of PTE (aHR = 0.6, CI 0.4-0.9) compared to those not using any AED.

CONCLUSION

The probability of developing PTE increased within the study period. The risk of developing PTE significantly increased with age, early seizure and TBI severity. Most of the individuals did not receive AED after TBI. There was no evidence suggesting AEDs helped to prevent PTE with the possible exception of acetazolamide. However, further studies may be needed to test the efficacy of acetazolamide in preventing PTE.

An estimation of global volume of surgically treatable epilepsy based on a systematic review and meta-analysis of epilepsy

OBJECTIVEEpilepsy is one of the most common neurological disorders, yet its global surgical burden has yet to be characterized. The authors sought to compile the most current epidemiological data to quantify global prevalence and incidence, and estimate global surgically treatable epilepsy. Understanding regional and global epilepsy trends and potential surgical volume is crucial for future policy efforts and resource allocation.METHODSThe authors performed a systematic literature review and meta-analysis to determine the global incidence, lifetime prevalence, and active prevalence of epilepsy; to estimate surgically treatable epilepsy volume; and to evaluate regional trends by WHO regions and World Bank income levels. Data were extracted from all population-based studies with prespecified methodological quality across all countries and demographics, performed between 1990 and 2016 and indexed on PubMed, EMBASE, and Cochrane. The current and annual new case volumes for surgically treatable epilepsy were derived from global epilepsy prevalence and incidence.RESULTSThis systematic review yielded 167 articles, across all WHO regions and income levels. Meta-analysis showed a raw global prevalence of lifetime epilepsy of 1099 per 100,000 people, whereas active epilepsy prevalence is slightly lower at 690 per 100,000 people. Global incidence was found to be 62 cases per 100,000 person-years. The meta-analysis predicted 4.6 million new cases of epilepsy annually worldwide, a prevalence of 51.7 million active epilepsy cases, and 82.3 million people with any lifetime epilepsy diagnosis. Differences across WHO regions and country incomes were significant. The authors estimate that currently 10.1 million patients with epilepsy may be surgical treatment candidates, and 1.4 million new surgically treatable epilepsy cases arise annually. The highest prevalences are found in Africa and Latin America, although the highest incidences are reported in the Middle East and Latin America. These regions are primarily low- and middle-income countries; as expected, the highest disease burden falls disproportionately on regions with the fewest healthcare resources.CONCLUSIONSUnderstanding of the global epilepsy burden has evolved as more regions have been studied. This up-to-date worldwide analysis provides the first estimate of surgical epilepsy volume and an updated comprehensive overview of current epidemiological trends. The disproportionate burden of epilepsy on low- and middle-income countries will require targeted diagnostic and treatment efforts to reduce the global disparities in care and cost. Quantifying global epilepsy provides the first step toward restructuring the allocation of healthcare resources as part of global healthcare system strengthening.

Development and validation of risk score to estimate 1-year late poststroke epilepsy risk in ischemic stroke patients

Objective

This study aimed to develop and validate a prognostic model for the 1-year risk of late poststroke epilepsy (PSE).

Materials and methods

We included patients initially diagnosed with ischemic stroke between 2003 and 2014 in a National Health Insurance claims-based cohort in Taiwan. Patients were further divided into development and validation cohorts based on their year of stroke diagnosis. Multivariable Cox regression with backward elimination was used to analyze the association between 1-year PSE and risk factors before and on stroke admission.

Results

In total, 1,684 (1.93%) and 725 (1.87%) ischemic stroke patients comprising the development and validation cohorts, respectively, experienced late PSE within 1 year after stroke. Seven clinical variables were examined to be independently associated with 1-year risk of PSE. We developed a risk score called "PSEiCARe" ranging from 0 to 16 points, comprising the following factors: prolonged hospital stay (>2 weeks, 1 point), seizure on admission (6 points), elderly patients (age ≥80 years, 1 point), intensive care unit stay on admission (3 points), cognitive impairment (dementia, 2 points), atrial fibrillation (2 points), and respiratory tract infection (pneumonia) on admission (1 point). Patients were further classified into low-, medium-, high-, and very-high-risk groups. The incidence (per 100 person-years) was 0.64 (95% CI: 0.56-0.71) for the low-risk, 2.62 (95% CI: 2.43-2.82) for the medium-risk, 10.3 (95% CI: 9.48-11.3) for the high-risk, and 28.2 (95% CI: 24.0-33.0) for the very-high-risk groups. Discrimination and calibration were satisfactory, with a Harrell's C of 0.762 in the development model and 0.792 in the validation model.

Conclusion

PSEiCARe is an easy-to-use prognostic score that integrates patient characteristics and clinical factors on stroke admission to predict 1-year PSE risk; it has the potential to assist individualized patient management and improve clinical practice, thereby preventing the occurrence of late PSE.

Association between environmental exposure to pesticides and epilepsy

There is increasing evidence of an association between long-term environmental exposure to pesticides and neurodegenerative disorders; however, the relationship with epilepsy has not been addressed thus far. This study was aimed at determining the prevalence and risk of developing epilepsy among people from South-East Spain living in areas of high vs. low exposure to pesticides based on agronomic data. The study population consisted of 4007 subjects with a diagnosis of epilepsy and 580,077 control subjects adjusted for age, sex and geographical area. Data were collected from hospital records of the Spanish health care system (basic minimum dataset) between the years 1998 and 2010. The prevalence of epilepsy was significantly higher in areas of greater pesticide use relative to areas of lesser use. Overall, an increased risk of epilepsy was observed in the population living in areas of high vs. low use of pesticides (OR: 1.65; p < 0.001). Although this study was exploratory in nature, the results suggest that environmental exposure to pesticides might increase the risk of having epilepsy.

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.

The direct cost of epilepsy in children: Evidence from the Medical Expenditure Panel Survey, 2003-2014

INTRODUCTION

Epilepsy is frequent in children and often requires complex healthcare interventions. There is a paucity of recent and detailed healthcare expenditures among children with epilepsy in the United States (US).

METHODS

Data on children (aged ≤17years) from the Medical Expenditure Panel Survey-Household Component (MEPS-HC) from 2003 to 2014 were analyzed. Unadjusted overall and specific cost components were compared between children with epilepsy and those without epilepsy. We used a two-part model with gamma distribution and log link for the estimation of independent incremental cost incurred by epilepsy in children. Unadjusted and adjusted mean expenditures and aggregate burden of epilepsy were estimated.

RESULTS

Out of 54,393,387 (weighted) US children, 457,873 (0.84%) had epilepsy. Children with epilepsy had nearly six times higher healthcare expenditure than those without epilepsy ($2024 [95% confidence interval (CI): 1917-2130] vs. $12,577 [95% CI: 7922-17,231]). Unadjusted inpatient expenditure for epilepsy ($4418 [95% CI: 1550-7285) was ten times higher than that for children without epilepsy, representing more than one-third of unadjusted total direct cost. The adjusted difference in medical expenditure between children with and those without epilepsy was $8317 (95% CI: 3701-13,363). The annual unadjusted aggregate cost of epilepsy in children was approximately $5.8 billion. The annual adjusted difference in cost of epilepsy between children with and those without epilepsy was $3.8 billion.

CONCLUSION

Unadjusted and adjusted medical expenditure among children with epilepsy is high. The high expenditure is essentially driven not only by inpatient expenditure but also by home healthcare, outpatient, and medication healthcare expenditures.

Changing the neurology policy landscape in the United States: Misconceptions and facts about epilepsy

Epilepsy has a relatively high prevalence, and diagnosis and treatment are often challenging. Seizure freedom without significant side effects is the ultimate goal for both physicians and patients, but not always achievable. In those cases, the treatment goals of patients and providers may differ. In the United States, many clinicians continue to prescribe older AEDs, even though newer AEDs have a more desirable safety and tolerability profile, fewer drug-drug interactions, and are associated with lower epilepsy-related hospital visits. Newer AEDs are more commonly prescribed by neurologists and epilepsy center physicians, highlighting the importance of access to specialty care. We report that antiepileptic drugs are not the dominant cost driver for patients with epilepsy and costs are considerably higher in patients with uncontrolled epilepsy. Poor drug adherence is considered a main cause of unsuccessful epilepsy treatment and is associated with increases in inpatient and emergency department admissions and related costs. Interventions and educational programs are needed to address the reasons for nonadherence. Coverage policies placing a higher cost burden on patients with epilepsy lead to lower treatment adherence, which can result in higher future health care spending. Epilepsy is lagging behind other neurological conditions in terms of funding and treatment innovation. Increased investment in epilepsy research may be particularly beneficial given current funding levels and the high prevalence of epilepsy.

Young people with epilepsy have an increased risk of eating disorder and poor quality diet

Objective

To investigate whether adolescents with epilepsy are at increased risk of having self-reported eating disorder symptoms and poor quality diet compared to young people from the general population.

Methods

We used data from the Health Profile for Children and Youth in Akershus Study, a cross-sectional population-based study based on a voluntary self-reported questionnaire. There were 19,995 participants (response rate 85%) aged 13-19 years; 247 (1.2%) reported a lifetime diagnosis of epilepsy. Odds ratios (OR) and 95% confidence intervals (CI) for eating disorders, unhealthy diet, dieting, satisfaction with looks, and participation in sports were estimated by using a logistic regression model. All estimates were adjusted for single parents and poor family economy.

Results

Children and adolescents with epilepsy had more eating disorders than their peers (OR 1.8, CI 1.0-3.0, p = 0.03). They were less satisfied with their own appearance (OR 0.7, CI 0.5-0.9, p = 0.02), and they eat more unhealthily (OR 1.7, CI 1.3-2.2, p = 0.001). Males with epilepsy were more likely to have been dieting (OR 3.1, CI 1.2-7.9, p = 0.02) and less satisfied with their own appearance (OR 0.4, CI 0.3-0.7, p < 0.001). Females with epilepsy were more likely to eat unhealthily (OR 1.7, CI 1.1-2.5, p = 0.01).

Significance

Adolescents with epilepsy are at increased risk of having eating disorder symptoms. They eat less healthily and are less satisfied with their looks. Health workers should be aware of this and bring diet and lifestyle into the dialogue with young people with epilepsy.

Five and 10 minute Apgar scores and risks of cerebral palsy and epilepsy: population based cohort study in Sweden

OBJECTIVE

To investigate associations between Apgar score at five and 10 minutes across the entire range of score values (from 0 to 10) and risks of childhood cerebral palsy or epilepsy, and to analyse the effect of changes in Apgar scores from five to 10 minutes after birth in infants born ≥37 completed weeks.

DESIGN, SETTING, AND PARTICIPANTS

Population based cohort study in Sweden, including 1 213 470 non-malformed live singleton infants, born at term between 1999 and 2012. Data on maternal and pregnancy characteristics and diagnoses of cerebral palsy and epilepsy were obtained by individual record linkages of nationwide Swedish registries.

EXPOSURES

Apgar scores at five and 10 minutes.

MAIN OUTCOME MEASURE

Cerebral palsy and epilepsy diagnosed up to 16 years of age. Adjusted hazard ratios were calculated, along with 95% confidence intervals.

RESULTS

1221 (0.1%) children were diagnosed as having cerebral palsy and 3975 (0.3%) as having epilepsy. Compared with children with an Apgar score of 10 at five minutes, the adjusted hazard ratio for cerebral palsy increased steadily with decreasing Apgar score: from 1.9 (95% confidence interval 1.6 to 2.2) for an Apgar score of 9 to 277.7 (154.4 to 499.5) for an Apgar score of 0. Similar and even stronger associations were obtained between Apgar scores at 10 minutes and cerebral palsy. Associations between Apgar scores and epilepsy were less pronounced, but increased hazard ratios were noted in infants with a five minute Apgar score of 7 or less and a 10 minute Apgar score of 8 or less. Compared with infants with an Apgar of 9-10 at both five and 10 minutes, hazard ratios of cerebral palsy and epilepsy were higher among infants with a five minute Apgar score of 7-8 and a 10 minute Apgar score of 9-10.

CONCLUSION

Risks of cerebral palsy and epilepsy are inversely associated with five minute and 10 minute Apgar scores across the entire range of Apgar scores.

People with epilepsy are diagnosed most often with unspecified epilepsy, followed by focal epilepsy, generalized convulsive epilepsy, and generalized nonconvulsive epilepsy-US MarketScan data, 2010-2015

The distribution of epilepsy types varies by age, etiology, provider diagnostic capabilities, and assessment criteria. No recent US study has examined the distribution of epilepsy types in a large, population-based sample of people with epilepsy. We used MarketScan data from January 1, 2010 through September 30, 2015, to estimate the proportion of epilepsy types among all (N=370,570) individuals diagnosed with epilepsy. We identified cases of epilepsy as individuals with at least one International Classification of Disease, 9th version (ICD-9) diagnostic code of 345.X and the use of at least one antiseizure drug described in the 2015 MarketScan Redbook. Unspecified epilepsy was more common (36.8%) than focal-localized epilepsy (24.6%), generalized convulsive epilepsy (23.8%), generalized nonconvulsive epilepsy (8.9%), other forms of epilepsy (5.2%), infantile spasm (0.3%), and epilepsia partialis continua (0.3%). The high proportion of epilepsy classified as unspecified might be lowered by improved training in epilepsy diagnosis and coding.

An update on the prevalence and incidence of epilepsy among older adults

OBJECTIVE

To estimate the prevalence and incidence of epilepsy among beneficiaries of Arizona Medicare aged 65 and over.

METHODS

An analysis of Medicare administrative claims data for 2009-2011 for the State of Arizona was conducted. Epilepsy was defined as a beneficiary who had either≥one claim with diagnostic code of 345.xx (epilepsy) or at least two claims with diagnosis code of 780.3x (seizure) ≥30days apart. Stroke-related and psychiatric comorbidities were determined by diagnostic codes. Average annual prevalence and incidence were calculated and stratified by demographic characteristics and comorbidities. Odds ratios (OR) and 95% confidence intervals (CI) were calculated as measures of effect for prevalence and incidence and the chi-square statistic was calculated to compare the proportions of epilepsy cases with and without comorbidities (alpha=0.05).

RESULTS

The overall average annual prevalence and incidence over the study period was 15.2/1000 and 6.1/1000, respectively. Relative to the 65-69 age group and White beneficiaries, the highest prevalence was observed for beneficiaries 85 years or older (19.8/1000, OR 1.66, 95% CI 1.53-1.81) and Native Americans (21.2/1000, OR 1.42, 95% CI 1.25-1.62). In contrast, the highest incidence rates were observed for beneficiaries 85 years and older (8.5/1000, OR 1.82, 95% CI 1.60-2.07) and for Black beneficiaries (8.7/1000, OR 1.44, 95% CI 1.12-1.86). The incidence rate for Native Americans was not significantly different from that for White beneficiaries (6.2/1000, OR 1.02, 95% CI 0.81-1.29). More than one quarter of all cases (25.7%) and 31% of incident cases had either stroke-related and/or psychiatric comorbidities (all p-values < 0.001).

CONCLUSIONS

Epilepsy is a significant neurological disease among Medicare beneficiaries 65 years and older. Beneficiaries aged 85 and older and Black and Native Americans experienced higher rates of epilepsy than other demographic subgroups compared to White beneficiaries.