Temporal trends in pre-surgical evaluations and epilepsy surgery in the U.S. from 1998 to 2009

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.

National 22-year epilepsy surgery landscape shows increasing open and minimally invasive pediatric epilepsy surgery

OBJECTIVES

A surgical "treatment gap" in pediatric epilepsy persists despite the demonstrated safety and effectiveness of surgery. For this reason, the national surgical landscape should be investigated such that an updated assessment may more appropriately guide health care efforts.

METHODS

In our retrospective cross-sectional observational study, the National Inpatient Sample (NIS) database was queried for individuals 0 to <18 years of age who had an International Classification of Diseases (ICD) code for drug-resistant epilepsy (DRE). This cohort was then split into a medical group and a surgical group. The former was defined by ICD codes for -DRE without an accompanying surgical code, and the latter was defined by DRE and one of the following epilepsy surgeries: any open surgery; laser interstitial thermal therapy (LITT); vagus nerve stimulation; or responsive neurostimulation (RNS) from 1998 to 2020. Demographic variables of age, gender, race, insurance type, hospital charge, and hospital characteristics were analyzed between surgical options. Continuous variables were analyzed with weight-adjusted quantile regression analysis, and categorical variables were analyzed by weight-adjusted counts with percentages and compared with weight-adjusted chi-square test results.

RESULTS

These data indicate an increase in epilepsy surgeries over a 22-year period, primarily due to a statistically significant increase in open surgery and a non-significant increase in minimally invasive techniques, such as LITT and RNS. There are significant differences in age, race, gender, insurance type, median household income, Elixhauser index, hospital setting, and size between the medical and surgical groups, as well as the procedure performed.

SIGNIFICANCE

An increase in open surgery and minimally invasive surgeries (LITT and RNS) account for the overall rise in pediatric epilepsy surgery over the last 22 years. A positive inflection point in open surgery is seen in 2005. Socioeconomic disparities exist between medical and surgical groups. Patient and hospital sociodemographics show significant differences between the procedure performed. Further efforts are required to close the surgical "treatment gap."

Use of Recommended Neurodiagnostic Evaluation Among Patients With Drug-Resistant Epilepsy

Importance

Interdisciplinary practice parameters recommend that patients with drug-resistant epilepsy (DRE) undergo comprehensive neurodiagnostic evaluation, including presurgical assessment. Reporting from specialized centers suggests long delays to referral and underuse of surgery; however, longitudinal data are limited to characterize neurodiagnostic evaluation among patients with DRE in more diverse US settings and populations.

Objective

To examine the rate and factors associated with neurodiagnostic studies and comprehensive evaluation among patients with DRE within 3 US cohorts.

Design, Setting, and Participants

A retrospective cross-sectional study was conducted using the Observational Medical Outcomes Partnership Common Data Model including US multistate Medicaid data, commercial claims data, and Columbia University Medical Center (CUMC) electronic health record data. Patients meeting a validated computable phenotype algorithm for DRE between January 1, 2015, and April 1, 2020, were included. No eligible participants were excluded.

Exposure

Demographic and clinical variables were queried.

Main Outcomes and Measures

The proportion of patients receiving a composite proxy for comprehensive neurodiagnostic evaluation, including (1) magnetic resonance or other advanced brain imaging, (2) video electroencephalography, and (3) neuropsychological evaluation within 2 years of meeting the inclusion criteria.

Results

A total of 33 542 patients with DRE were included in the Medicaid cohort, 22 496 in the commercial insurance cohort, and 2741 in the CUMC database. A total of 31 516 patients (53.6%) were women. The proportion of patients meeting the comprehensive evaluation main outcome in the Medicaid cohort was 4.5% (n = 1520); in the commercial insurance cohort, 8.0% (n = 1796); and in the CUMC cohort, 14.3% (n = 393). Video electroencephalography (24.9% Medicaid, 28.4% commercial, 63.2% CUMC) and magnetic resonance imaging of the brain (35.6% Medicaid, 43.4% commercial, 52.6% CUMC) were performed more regularly than neuropsychological evaluation (13.0% Medicaid, 16.6% commercial, 19.2% CUMC) or advanced imaging (3.2% Medicaid, 5.4% commercial, 13.1% CUMC). Factors independently associated with greater odds of evaluation across all 3 data sets included the number of inpatient and outpatient nonemergency epilepsy visits and focal rather than generalized epilepsy.

Conclusions and Relevance

The findings of this study suggest there is a gap in the use of diagnostic studies to evaluate patients with DRE. Care setting, insurance type, frequency of nonemergency visits, and epilepsy type are all associated with evaluation. A common data model can be used to measure adherence with best practices across a variety of observational data sources.

Modeling and in vivo experimental validation of 1,064 nm laser interstitial thermal therapy on brain tissue

Introduction

Laser interstitial thermal therapy (LITT) at 1064 nm is widely used to treat epilepsy and brain tumors; however, no numerical model exists that can predict the ablation region with careful in vivo validation.

Methods

In this study, we proposed a model with a system of finite element methods simulating heat transfer inside the brain tissue, radiative transfer from the applicator into the brain tissue, and a model for tissue damage.

Results

To speed up the computation for practical applications, we also validated P1-approximation as an efficient and fast method for calculating radiative transfer by comparing it with Monte Carlo simulation. Finally, we validated the proposed numerical model in vivo on six healthy canines and eight human patients with epilepsy and found strong agreement between the predicted temperature profile and ablation area and the magnetic resonance imaging-measured results.

Discussion

Our results demonstrate the feasibility and reliability of the model in predicting the ablation area of 1,064 nm LITT, which is important for presurgical planning when using LITT.

Effect of Race and Insurance Type on Access to, and Outcomes of, Epilepsy Surgery: A Literature Review

BACKGROUND

Despite higher rates of seizure freedom, a large proportion of patients with medically refractory seizures who could benefit from epilepsy surgery do not receive surgical treatment. This literature review describes the association of race and insurance status with epilepsy surgery access and outcomes.

METHODS

Searches in Scopus and PubMed databases related to disparities in epilepsy surgery were conducted. The inclusion criteria consisted of data that could be used to compare epilepsy surgery patient access and outcomes by insurance or race in the United States. Two independent reviewers determined article eligibility.

RESULTS

Of the 289 studies reviewed, 26 were included. Most of the studies were retrospective cohort studies (23 of 26) and national admissions database studies (13 of 26). Of the 17 studies that evaluated epilepsy surgery patient demographics, 11 showed that Black patients were less likely to receive surgery than were White patients or had an increased time to surgery from seizure onset. Nine studies showed that patients with private insurance were more likely to undergo epilepsy surgery and have shorter time to surgery compared with patients with public insurance. No significant association was found between the seizure recurrence rate after surgery with insurance or race.

CONCLUSIONS

Black patients and patients with public insurance are receiving epilepsy surgery at lower rates after a prolonged waiting period compared with other patients with medically refractory epilepsy. These results are consistent across the current reported literature. Future efforts should focus on additional characterization and potential causes of these disparities to develop successful interventions.

Association Between Characteristics of National Association of Epilepsy Centers and Reported Utilization of Specific Surgical Techniques

BACKGROUND AND OBJECTIVE

Nearly one-third of persons with epilepsy will continue having seizures despite trialing multiple antiseizure medications. Epilepsy surgery may be beneficial in these cases, and evaluation at a comprehensive epilepsy center is recommended. Numerous palliative and potentially curative approaches exist, and types of surgery performed may be influenced by center characteristics. This article describes epilepsy center characteristics associated with epilepsy surgery access and volumes in the United States.

METHODS

We analyzed National Association of Epilepsy Centers 2019 annual report and supplemental survey data obtained with responses from 206 adult epilepsy center directors and 136 pediatric epilepsy center directors in the United States. Surgical treatment volumes were compiled with center characteristics, including US Census region. We used multivariable modeling with zero-inflated Poisson regression models to present ORs and incidence rate ratios of receiving a given surgery type based on center characteristics.

RESULTS

The response rate was 100% with individual element missingness less than 4% across 352 observations undergoing univariate analysis. Multivariable models included 319 complete observations. Significant regional differences were present. The rates of laser interstitial thermal therapy (LITT) were lower at centers in the Midwest (incidence rate ratio [IRR] 0.74, 95% CI 0.59-0.92; p = 0.006) and Northeast (IRR 0.77, 95% CI 0.61-0.96; p = 0.022) compared with those in the South. Conversely, responsive neurostimulation implantation rates were higher in the Midwest (IRR 1.45, 95% CI 1.1-1.91; p = 0.008) and West (IRR 1.91, 95% CI 1.49-2.44; p < 0.001) compared with the South. Center accreditation level, institution type, demographics, and resources were also associated with variations in access and rates of potentially curative and palliative surgical interventions.

DISCUSSION

Epilepsy surgery procedure volumes are influenced by US epilepsy center region and other characteristics. These variations may affect access to specific surgical treatments for persons with drug resistant epilepsy across the United States.

Utilization of epilepsy surgery in the United States: A study of the National Inpatient Sample investigating the roles of race, socioeconomic status, and insurance

Background:

Epilepsy is estimated to affect 70 million people worldwide and is medically refractory in 30% of cases.

Methods:

This is a retrospective cross-sectional study using a US database from 2012 to 2014 to identify patients aged ≥18 years admitted to the hospital with epilepsy as the primary diagnosis. The sampled population was weighted using Healthcare Cost and Utilization Project guidelines. Procedural ICD-9 codes were utilized to stratify the sampled population into two cohorts: resective surgery and implantation or stimulation procedure.

Results:

Query of the database yielded 152,925 inpatients, of which 8535 patients underwent surgical intervention. The nonprocedural group consisted of 76,000 White patients (52.6%) and 28,390 Black patients (19.7%) while the procedural group comprised 5550 White patients (64%) and 730 Black patients (8.6%) (P < 0.001). Patients with Medicare were half as likely to receive a surgical procedure (14.8% vs. 28.4%) while patients with private insurance were twice as likely to receive a procedure (53.4% vs. 29.3%), both were statistically significant (P < 0.01). Those in the lowest median household income quartile by zip code (<$40,000) were 68% less likely to receive a procedure (21.5% vs. 31.4%) while the highest income quartile was 133% more likely to receive a procedure (26.1% vs. 19.5%). Patients from rural and urban nonteaching hospitals were, by a wide margin, less likely to receive a surgical procedure.

Conclusion:

We demonstrate an area of need and significant improvement at institutions that have the resources and capability to perform epilepsy surgery. The data show that institutions may not be performing enough epilepsy surgery as a result of racial and socioeconomic bias. Admissions for epilepsy continue to increase without a similar trend for epilepsy surgery despite its documented effectiveness. Race, socioeconomic status, and insurance all represent significant barriers in access to epilepsy surgery. The barriers can be remedied by improving referral patterns and implementing cost-effective measures to improve inpatient epilepsy services in rural and nonteaching hospitals.

Conceptualization and implementation of an interdisciplinary clinic for children with drug-resistant epilepsy during the COVID-19 pandemic

OBJECTIVE

To describe the rapid conceptualization and implementation of an interdisciplinary epilepsy clinic for children with drug-resistant epilepsy (DRE) at Arkansas Children's Hospital (ACH) during the COVID 19 pandemic.

METHODS

Focusing on care design and care coordination for children with DRE, multiple stakeholder groups decided to implement a clinic after the systematic rating of constructs present in a theoretical meta-analytic framework. Based on the projected success, the new interdisciplinary clinic (composed of an epileptologist, a neurosurgeon, and a neuropsychologist and coordinated by a full-time nurse) was established. Clinic operations were further refined through discussions with patients, families, and care providers. We collected data retrospectively (August 2020 to June 2021) to determine referral patterns, clinic scheduling metrics, patient characteristics, clinical recommendations, and epilepsy quality metrics.

RESULTS

Of the 32 Consolidated Framework for Implementation Research constructs assessed, 24 were positively rated to predict a high probability of successful implementation of the clinic. For approximately 100 patient visits, appearance and usage rates were >75%, yielding a clinic utilization rate of approximately 60%. Among 76 unique patients (average age of 12 years, 60% focal epilepsy), 39 patients (51.3%) were deemed eligible for epilepsy surgery evaluation. The majority of the patients (53.9%) were advised for additional diagnostic testing, and 31.6% of patients were scheduled for vagus nerve stimulation. More patients (33%) had changes in their existing anti-seizure medication (ASM) regimen rather than an addition of a new ASM (7.9%). Standardized epilepsy quality measures showed >80% to 90% adherence in 3 (reproductive counseling, depression and anxiety screening, documentation of seizure frequency) out of 4 metrics.

SIGNIFICANCE

This is the first study to show that an interdisciplinary clinic can be a valuable attribute of care models in high-need children with DRE by enabling comprehensive one-stop service for diagnostic evaluation, surgical consideration, and brief assessment of psychiatric comorbidities without compromising consensus-based best practices.

The Missed Value of Underutilizing Pediatric Epilepsy Surgery: A Systematic Review

Pediatric epilepsy surgery is underutilized. Only 1%-11% of children with drug resistant epilepsy (DRE) undergo surgical treatment, or less than half of those estimated to benefit. We conducted a systematic review of articles published in PubMed, EMBASE, and Web of Science in order to study the factors related to surgery underutilization as well as the impact on both the individual and the healthcare system. Our review demonstrates multiple factors leading to underutilization, including family misconceptions about epilepsy surgery, lack of provider knowledge, as well as systemic health disparities. While the upfront cost of epilepsy surgery is significant, the long-term financial benefits and reduced health resource utilization tilt the economic advantage in favor of surgery in children with DRE. Additionally, timely interventions improve seizure and cognitive outcomes with low risk of complications. Further interventions are needed at the levels of family, provider, and the healthcare system to increase access to pediatric epilepsy surgery.

Underutilization of epilepsy surgery: Part II: Strategies to overcome barriers

Interventions focused on utilization of epilepsy surgery can be divided into groups: those that improve patients' access to surgical evaluation and those that facilitate completion of the surgical evaluation and treatment. Educational intervention, technological innovation, and effective coordination and communication can significantly improve patients' access to surgery. Patient and public facing, individualized (analog and/or digital) communication can raise awareness and acceptance of epilepsy surgery. Educational interventions aimed at providers may mitigate knowledge gaps using practical and concise consensus statements and guidelines, while specific training can improve awareness around implicit bias. Innovative technology, such as clinical decision-making toolkits within the electronic medical record (EMR), machine learning techniques, online decision-support tools, nomograms, and scoring algorithms can facilitate timely identification of appropriate candidates for epilepsy surgery with individualized guidance regarding referral appropriateness, postoperative seizure freedom rate, and risks of complication after surgery. There are specific strategies applicable for epilepsy centers' success: building a multidisciplinary setup, maintaining/tracking volume and complexity of cases, collaborating with other centers, improving surgical outcome with reduced complications, utilizing advanced diagnostics tools, and considering minimally invasive surgical techniques. Established centers may use other strategies, such as multi-stage procedures for multifocal epilepsy, advanced functional mapping with tailored surgery for epilepsy involving the eloquent cortex, and generation of fresh hypotheses in cases of surgical failure. Finally, improved access to epilepsy surgery can be accomplished with policy changes (e.g., anti-discrimination policy, exemption in transportation cost, telehealth reimbursement policy, patient-centered epilepsy care models, pay-per-performance models, affordability and access to insurance, and increased funding for research). Every intervention should receive regular evaluation and feedback-driven modification to ensure appropriate utilization of epilepsy surgery.

Postoperative outcomes and surgical ratio at a newly established epilepsy center: The first 100 procedures

PURPOSE

To describe the patients' characteristics, surgical ratio, and outcomes following epilepsy surgery at the newly established Epilepsy Center Frankfurt Rhine-Main.

METHODS

We retrospectively studied the first 100 consecutive patients, including adult (n = 77) and pediatric (n = 23) patients, with drug-resistant epilepsy who underwent resective or ablative surgical procedures at a single, newly established epilepsy center. Patient characteristics, seizure and neuropsychological outcomes, histopathology, complications, and surgical ratio were analyzed.

RESULTS

The mean patient age was 28.8 years (children 10.6 years, adults 34.2 years). The mean epilepsy duration was 11.9 years (children 3.9 years, adults 14.3 years), and the mean follow-up was 1.5 years. At the most recent visit, 64% of patients remained completely seizure free [Engel IA]. The rates of perioperative complications and unexpected new neurological deficits were 5%, each. The proportion of patients showing deficits in one or more cognitive domains increased six months after surgery and decreased to presurgical proportions after two years. Symptoms of depression were significantly decreased and quality of life was significantly increased after surgery. The surgical ratio was 25.3%.

CONCLUSION

Similar postsurgical outcomes were achieved at a newly established epilepsy center compared with long-standing epilepsy centers. The lower time to surgery may reflect a general decrease in time to surgery over the last decade or the improved accessibility of a new epilepsy center in a previously underserved area. The surgical ratio was not lower than reported for established centers.

The Humanistic and Economic Burden of Pediatric Focal Seizures in the United States

OBJECTIVE

To better understand the humanistic and economic burden of focal seizures in children 2-12 years old.

METHODS

We conducted a targeted literature review by searching MEDLINE for English-language publications reporting on children 2-12 years old with focal seizures published in the United States since 2008.

RESULTS

Thirty-five publications were included. Incidence of focal seizures was 23.2 to 47.1 per 100,000 children per year; prevalence was 2.0 per 1,000 children, and ranged from 1.6 - 2.6 per 1,000 in patients of any age. Life expectancy was 47.3-61.8 years among children 3-12 years old. Patients took several antiepileptic drugs and experienced frequent seizures, sleep disorders, mood disorders, migraine, and seizure-related injuries (eg, bone fractures, sprains, open wounds). Children with focal seizures scored below average on cognitive assessments and up to 42%, 16%, and 19% had depression, anxiety, and attention-deficit disorder, respectively. Patients of any age had about 10 outpatient visits (2 epilepsy-related), 2 inpatient visits (less than 1 epilepsy-related), and 24 procedures (1 epilepsy-related) per year. Medication adherence was low: only half of pediatric patients maintained ≥90% adherence over 6 months. Annual total health care costs among patients of any age ranged from $18,369 - 38,549; first-year total health care costs for children were $19,883.

CONCLUSIONS

Incidence and prevalence of focal seizures is high and the humanistic and economic burdens are significant. Future studies focused exclusively on children with focal seizures are needed to more precisely describe the burden. We also suggest further research and implementation of methods to improve medication adherence as an approach to lessen burden on these young patients.

Deciphering the surgical treatment gap for drug-resistant epilepsy (DRE): A literature review

Patients with drug-resistant epilepsy (DRE) rarely achieve seizure freedom with medical therapy alone. Despite being safe and effective for select patients with DRE, epilepsy surgery remains heavily underutilized. Multiple studies have indicated that the overall rates of surgery in patients with DRE have stagnated in recent years and may be decreasing, even when hospitalizations for epilepsy-related problems are on the rise. Ultimately, many patients with DRE who might otherwise benefit from surgery continue to have intractable seizures, lacking access to the full spectrum of available treatment options. In this article, we review the various factors accounting for the persistent underutilization of epilepsy surgery and uncover several key themes, including the persistent knowledge gap among physicians in identifying potential surgical candidates, lack of coordinated patient care, patient misconceptions of surgery, and socioeconomic disparities impeding access to care. Moreover, factors such as the cost and complexity of the preoperative evaluation, a lack of federal resource allocation for the research of surgical therapies for epilepsy, and difficulties recruiting patients to clinical trials all contribute to this multifaceted dilemma.

Trends in epilepsy diagnosis and surgery in western China during 2009-2017

OBJECTIVE

Despite the strong evidence for the efficacy of surgery to treat temporal lobe epilepsy, the number of such surgeries has plateaued in western countries. This study examined trends in the number of epilepsy cases diagnosed, number of surgeries performed, and certain characteristics of surgery patients in western China between January 2009 and December 2017.

METHODS

Data were obtained for a population-based sample from a healthcare information system, as well as for a patient population from West China Hospital. Age at epilepsy onset, age at surgery, duration of epilepsy, and type of epilepsy pathology based on surgical samples were analyzed.

RESULTS

Data were obtained for 14,710 hospitalizations from the healthcare system and 17,302 hospitalizations from West China Hospital. The number of hospitalizations, but not the number of epilepsy surgeries, increased during the study period. Patients' age at epilepsy onset, age at surgery or epilepsy duration did not change significantly during the study period.

SIGNIFICANCE

Our analysis suggests that in western China, as in western countries, the number of temporal epilepsy surgeries has plateaued. In contrast, disease-modifying factors have not changed over time in western China. Further studies are needed to explore what may contribute to these findings.

"Time is Brain"-How early should surgery be done in drug-resistant TLE?

OBJECTIVES

To explore the effect of duration of epilepsy and delay in surgery on seizure outcome in patients operated for drug-resistant temporal lobe epilepsy (TLE).

MATERIALS & METHODS

A total of 664 consecutive patients who underwent anterior temporal lobectomy (ATL) for TLE from 1995 to 2008 formed the study cohort. We divided them into two, one as seizure-free with or without antiepileptic drugs after ATL as "good outcome" (Engel class I a) and seizures of any type, any time after surgery as "poor outcome." The probability of seizure freedom/seizure recurrence based on the duration of epilepsy was compared using Kaplan-Meier curves, univariate Cox regression survival analysis, and multivariate Cox proportional hazards regression model.

RESULTS

A total of 136 children and 528 adults underwent ATL during this period. Mean duration of epilepsy pre-ATL was 17.1 + 9.4 years. At mean follow-up of 8.5 years, 331 patients (49.8%) had good outcome and 333 (50.2%) had poor outcome. The hazard of seizure recurrence linearly increased with duration of epilepsy pre-ATL, from 1.5 (duration of epilepsy, 5-10 years) to 1.9 (duration of epilepsy, 10-15 years) to 2 (duration of epilepsy over 15 years). In addition, encephalitis as antecedent, bilateral mesial temporal sclerosis in MRI, normal histopathology, and spikes in postoperative EEG at 3 months and 1 year predicted poor seizure outcome.

CONCLUSIONS

"Epilepsy duration" independently predicted both short- and long-term seizure outcome after surgery in TLE. "Lost years" translate into poor seizure outcome after ATL. Therefore, all cases of drug-resistant TLE should be referred to a surgical center at the earliest.

European trends in epilepsy surgery

OBJECTIVE

Resective surgery is effective in treating drug-resistant focal epilepsy, but it remains unclear whether improved diagnostics influence postsurgical outcomes. Here, we compared practice and outcomes over 2 periods 15 years apart.

METHODS

Sixteen European centers retrospectively identified 2 cohorts of children and adults who underwent epilepsy surgery in the period of 1997 to 1998 (n = 562) or 2012 to 2013 (n = 736). Data collected included patient (sex, age) and disease (duration, localization and diagnosis) characteristics, type of surgery, histopathology, Engel postsurgical outcome, and complications, as well as imaging and electrophysiologic tests performed for each case. Postsurgical outcome predictors were included in a multivariate logistic regression to assess the strength of date of surgery as an independent predictor.

RESULTS

Over time, the number of operated cases per center increased from a median of 31 to 50 per 2-year period (p = 0.02). Mean disease duration at surgery decreased by 5.2 years (p < 0.001). Overall seizure freedom (Engel class 1) increased from 66.7% to 70.9% (adjusted p = 0.04), despite an increase in complex surgeries (extratemporal and/or MRI negative). Surgeries performed during the later period were 1.34 times (adjusted odds ratio; 95% confidence interval 1.02-1.77) more likely to yield a favorable outcome (Engel class I) than earlier surgeries, and improvement was more marked in extratemporal and MRI-negative temporal epilepsy. The rate of persistent neurologic complications remained stable (4.6%-5.3%, p = 0.7).

CONCLUSION

Improvements in European epilepsy surgery over time are modest but significant, including higher surgical volume, shorter disease duration, and improved postsurgical seizure outcomes. Early referral for evaluation is required to continue on this encouraging trend.

Readmission Following Surgical Resection for Intractable Epilepsy: Nationwide Rates, Causes, Predictors, and Outcomes

BACKGROUND

Hospital readmissions can be detrimental to patients and may interfere with the potential benefits of the therapeutic procedure. Government agencies have begun to focus on reducing readmissions; however, the etiology of readmissions is lacking.

OBJECTIVE

To report the national rates, risk factors, and outcomes associated with 30- and 90-d readmissions following surgery for intractable epilepsy.

METHODS

We queried the Nationwide Readmissions Database from January to September 2013 using International Classification of Diseases, Ninth Edition, Clinical Modification codes to identify all patients with intractable epilepsy, who underwent hemispherectomy (01.52), brain lobectomy (01.53), amydalohippocampectomy, or partial lobectomy (01.59). Predictor variables included epilepsy type, presurgical diagnostic testing, surgery type, medical complications, surgical complications, and discharge disposition.

RESULTS

In 1587 patients, the 30- and 90-d readmission rates were 11.5% and 16.8%, respectively. The most common reasons for readmission were persistent epilepsy, video electroencephalography monitoring, postoperative infection, and postoperative central nervous system complication. In multivariable analysis, risk factors associated with both 30- and 90-d readmission were Medicare payer status, lowest quartile of median income, depression, hemispherectomy, and postoperative complications (P &lt; .05). The only unique predictor of 30-d readmission was small bedsize hospital (P = .001). Readmissions within 30 d were associated with longer length of stay (6.8 vs 5.8 d), greater costs ($18 660 vs $15 515), and increased adverse discharges (26.4% vs 21.8%).

CONCLUSION

Following epilepsy surgery, most readmissions that occurred within 30 d can be attributed to management of persistent epilepsy and predicted by Medicare payer status, depression, and complications. These data can assist the clinician in preventing readmissions and assist policy makers determine which admissions are potentially avoidable.

Epidemiologist's view: Addressing the epilepsy surgery treatment gap with minimally-invasive techniques

Despite the fact that epilepsy surgery is both safe and effective, a considerable "surgical treatment gap" remains in that most persons who are eligible for surgery do not receive it. It has been argued that epilepsy surgery is one of the most underutilized of all accepted medical treatments in the world. In this article, we review the epidemiology of the epilepsy surgery treatment gap, and consider the role minimally-invasive epilepsy surgery may play in reducing this gap.

Thirty-day postoperative morbidity and mortality after temporal lobectomy for medically refractory epilepsy

OBJECTIVE

Temporal lobectomy is a well-established treatment modality for the management of medically refractory epilepsy in appropriately selected patients. The aim of this study was to assess 30-day morbidity and mortality after temporal lobectomy in cases registered in a national database.

METHODS

A retrospective cohort analysis was conducted using a multiinstitutional surgical registry compiled between 2006 and 2014. The authors identified patients who underwent anterior temporal lobectomy and/or amygdalohippocampectomy for a primary diagnosis of intractable epilepsy. Univariate and multivariable analyses with regard to patient demographics, comorbidities, operative characteristics, and 30-day outcomes were applied.

RESULTS

A total of 216 patients were included in the study. The median age was 38 years and 46% of patients were male. The median length of stay was 3 days and the 30-day mortality rate was 1.4%. Fourteen patients (6.5%) developed at least one major complication. Return to the operating room was observed in 7 patients (3.2%). Readmission within 30 days and discharge to a location other than home were available for 2011–2014 (n = 155) and occurred in 11% and 10.3% of patients, respectively. Multivariable regression analysis revealed that increasing age was an independent predictor of discharge disposition other than home and that male sex was a significant risk factor for the development of a major complication. Interestingly, the presence of the attending neurosurgeon and a resident during the procedure was significantly associated with decreased odds of prolonged length of stay (i.e., > 75th percentile [5 days]) and discharge to a location other than home.

CONCLUSIONS

Using a multiinstitutional surgical registry, 30-day outcome data after temporal lobectomy for medically intractable epilepsy demonstrates a mortality rate of 1.4%, a major complication rate of 6.5%, and a readmission rate of 11%. Temporal lobectomy is an extremely effective therapy for seizures originating there—however, surgical intervention must be weighed against its morbidity and mortality outcomes.

Thirty-day outcomes in pediatric epilepsy surgery

PURPOSE

The aim of this study was to use the multicenter American College of Surgeons National Surgical Quality Improvement Program-Pediatric (NSQIP-P) to evaluate and identify risk factors for 30-day adverse events in children undergoing epilepsy surgery.

METHODS

Using the 2015 NSQIP-P database, we identified children (age 0-18 years) undergoing pediatric epilepsy surgery and analyzed NSQIP-defined complications, unplanned reoperations, and unplanned readmissions. Multivariable logistic regression analysis was performed using perioperative data to identify risk factors for adverse events within 30 days of the index procedure.

RESULTS

Two hundred eight pediatric patients undergoing epilepsy surgery were identified for the year 2015 in the NSQIP-P database. The majority of patients were male (51.8%) and white (72.9%). The median age was 10 years. Neurological and neuromuscular comorbidities were seen in 62.5% of patients. Surgical blood loss and transfusion was the most common overall NSQIP-defined event (15.7%) and was reported in 40% with hemispherectomy. Nineteen patients (6.8%) had an unplanned reoperation and 20 patients (7.1%) had an unplanned readmission. Multivariable logistic regression analysis showed that African American patients (OR 3.26, 95% CI 1.29-8.21, p = 0.01) and hemispherectomy (OR 3.05, 95% CI 1.4-6.65, p = 0.01) were independently associated with NSQIP-defined complications. Patients undergoing hemispherectomy (OR 4.11, 95% CI 1.48-11.42, p = 0.01) were also at significantly higher risk of unplanned readmission after pediatric epilepsy surgery.

CONCLUSIONS

Data from the 2015 NSQIP-P database showed that hemispherectomy was significantly associated with higher perioperative events in children undergoing epilepsy surgery. Quality improvement initiatives for hemispherectomy should target surgical blood loss and wound-related complications. Racial disparities in access to cranial pediatric epilepsy surgery and perioperative complications were also highlighted in the present study.

Trends in intracranial monitoring for pediatric medically intractable epilepsy

Objective

To retrospectively examine nationwide trends in intracranial monitoring (ICM) for pediatric medically intractable epilepsy (MIE) from 2000 to 2012.

Methods

The Healthcare Cost and Utilization Project Kids' Inpatient Database was analyzed to identify admissions with ICD-9-CM codes corresponding to MIE and ICM from 2000 to 2012, inclusive. Associations between independent variables and outcomes were tested using χ2 test or Fisher exact test. A multivariate logistic regression analysis of variables associated with ICM was completed using stepwise selection. The Cochran-Armitage test was used to test for trend of a variable over the study period.

Results

The number of ICM procedures increased over the study period; however, secondary to large increases in the number of MIE admissions, the rate of ICM declined from 5.39% in 2000 to 2.56% in 2012 (p < 0.001). Despite this decline, ICM increasingly resulted in resective epilepsy procedures. In 2000, only 45.18% of ICM cases led to resective epilepsy surgery, which increased to 75.83% by 2012 (p < 0.001). ICM complication rates were comparable to, if not lower than, standard resective surgery. Disparities in access to ICM exist, with African American individuals and those with Medicaid significantly less likely to undergo ICM.

Conclusion

In this nationwide characterization of pediatric ICM trends, we identified a slight, significant downward trend in the rate of utilization of ICM for MIE. This was secondary to substantial increases in the number of hospital admissions for MIE. Reasons for this large increase and why it has not led to increased rates of ICM warrant further investigation.

Long-term reduction of health care costs and utilization after epilepsy surgery

OBJECTIVE

To assess long-term direct medical costs, health care utilization, and mortality following resective surgery in persons with uncontrolled epilepsy.

METHODS

Retrospective longitudinal cohort study of Medicaid beneficiaries with epilepsy from 2000 to 2008. The study population included 7,835 persons with uncontrolled focal epilepsy ages 18-64 years, with an average follow-up time of 5 years. Of these, 135 received surgery during the study period. To account for selection bias, we used risk-set optimal pairwise matching on a time-varying propensity score, and inverse probability of treatment weighting. Repeated measures generalized linear models were used to model utilization and cost outcomes. Cox proportional hazard was used to model survival.

RESULTS

The mean direct medical cost difference between the surgical group and control group was $6,806 after risk-set matching. The incidence rate ratio of inpatient, emergency room, and outpatient utilization was lower among the surgical group in both unadjusted and adjusted analyses. There was no significant difference in mortality after adjustment. Among surgical cases, mean annual costs per subject were on average $6,484 lower, and all utilization measures were lower after surgery compared to before.

SIGNIFICANCE

Subjects that underwent epilepsy surgery had lower direct medical care costs and health care utilization. These findings support that epilepsy surgery yields substantial health care cost savings.

Epilepsy surgery in the United States: Analysis of data from the National Association of Epilepsy Centers

OBJECTIVE

To examine trends in epilepsy-related surgical procedures performed at major epilepsy centers in the US between 2003 and 2012, and in the service provision infrastructure of epilepsy centers over the same time period.

METHODS

We analyzed data from the National Association of Epilepsy Centers' (NAEC) annual surveys. The total annual figures, annual average figures per center and annual rates of each surgical procedure based on US population numbers for that year were calculated. Additional information on center infrastructure and manpower was also examined.

RESULTS

The number of the NAEC's level 3 and level 4 epilepsy centers submitting annual survey reports increased from 37 centers in 2003 to 189 centers in 2012. The average reported number of Epilepsy Monitoring Unit (EMU) beds per center increased from 7 beds in 2008 to 8 beds in 2012. Overall annual EMU admission rates doubled between 2008 and 2012 but the average number of EMU admissions and epilepsy surgeries performed per center declined over the same period. The annual rate of anterior temporal lobectomies (ATL) for mesial temporal sclerosis (MTS) declined by >65% between 2006 and 2010. The annual rate of extratemporal surgery exceeded that of ATL for MTS from 2008 onwards, doubled between 2007 and 2012 and comprised 38% of all resective surgeries in 2012. Vagus nerve stimulator implant rates consistently increased year on year and exceeded resective surgeries in 2011 and 2012.

CONCLUSION

The last decade has seen a major change in the US epilepsy surgery landscape. Temporal lobectomies, particularly for MTS, have declined despite an increase in EMU admissions. On the other hands, case complexity correspondingly increased as evidenced by more extratemporal surgery, intracranial recordings and palliative procedures.

National trends and complication rates for invasive extraoperative electrocorticography in the USA

Invasive electrocorticography (ECoG) is used in patients when it is difficult to localize epileptogenic foci for potential surgical resection. As MR neuroimaging has improved over the past decade, we hypothesized the utilization of ECoG diminishing over time. Using the USA Nationwide Inpatient Sample, we collected demographic and complication data on patients receiving ECoG over the years 1988-2008 and compared this to patients with medically refractory epilepsy during the same time period. A total of 695 cases using extraoperative ECoG were identified, corresponding to 3528 cases nationwide and accounting for 1.1% of patients with refractory epilepsy from 1988-2008. African Americans were less likely to receive ECoG than whites, as were patients with government insurance in comparison to those with private insurance. Large, urban, and academic hospitals were significantly more likely to perform ECoG than smaller, rural, and private practice institutions. The most frequent complication was cerebrospinal fluid leak (11.7%) and only one death was reported from the entire cohort, corresponding to an estimated six patients nationally. Invasive ECoG is a relatively safe procedure offered to a growing number of patients with refractory epilepsy each year. However, these data suggest the presence of demographic disparities in those patients receiving ECoG, possibly reflecting barriers due to race and socioeconomic status. Among patients with nonlocalized seizures, ECoG often represents their only hope for surgical treatment. We therefore must further examine the indications and efficacy of ECoG, and more work must be done to understand if and why ECoG is preferentially performed in select socioeconomic groups.

Increasing utilization of pediatric epilepsy surgery in the United States between 1997 and 2009

OBJECTIVE

To examine national trends of pediatric epilepsy surgery usage in the United States between 1997 and 2009.

METHODS

We performed a serial cross-sectional study of pediatric epilepsy surgery using triennial data from the Kids' Inpatient Database from 1997 to 2009. The rates of epilepsy surgery for lobectomies, partial lobectomies, and hemispherectomies in each study year were calculated based on the number of prevalent epilepsy cases in the corresponding year. The age-race-sex adjusted rates of surgeries were also estimated. Mann-Kendall trend test was used to test for changes in the rates of surgeries over time. Multivariable regression analysis was also performed to estimate the effect of time, age, race, and sex on the annual incidence of epilepsy surgery.

RESULTS

The rates of pediatric epilepsy surgery increased significantly from 0.85 epilepsy surgeries per 1,000 children with epilepsy in 1997 to 1.44 epilepsy surgeries per 1,000 children with epilepsy in 2009. An increment in the rates of epilepsy surgeries was noted across all age groups, in boys and girls, all races, and all payer types. The rate of increase was lowest in blacks and in children with public insurance. The overall number of surgical cases for each study year was lower than 35% of children who were expected to have surgery, based on the estimates from the Connecticut Study of Epilepsy.

SIGNIFICANCE

In contrast to adults, pediatric epilepsy surgery numbers have increased significantly in the past decade. However, epilepsy surgery remains an underutilized treatment for children with epilepsy. In addition, black children and those with public insurance continue to face disparities in the receipt of epilepsy surgery.

Rates and predictors of seizure freedom in resective epilepsy surgery: an update

Epilepsy is a debilitating neurological disorder affecting approximately 1 % of the world's population. Drug-resistant focal epilepsies are potentially surgically remediable. Although epilepsy surgery is dramatically underutilized among medically refractory patients, there is an expanding collection of evidence supporting its efficacy which may soon compel a paradigm shift. Of note is that a recent randomized controlled trial demonstrated that early resection leads to considerably better seizure outcomes than continued medical therapy in patients with pharmacoresistant temporal lobe epilepsy. In the present review, we provide a timely update of seizure freedom rates and predictors in resective epilepsy surgery, organized by the distinct pathological entities most commonly observed. Class I evidence, meta-analyses, and individual observational case series are considered, including the experiences of both our institution and others. Overall, resective epilepsy surgery leads to seizure freedom in approximately two thirds of patients with intractable temporal lobe epilepsy and about one half of individuals with focal neocortical epilepsy, although only the former observation is supported by class I evidence. Two common modifiable predictors of postoperative seizure freedom are early operative intervention and, in the case of a discrete lesion, gross total resection. Evidence-based practice guidelines recommend that epilepsy patients who continue to have seizures after trialing two or more medication regimens should be referred to a comprehensive epilepsy center for multidisciplinary evaluation, including surgical consideration.

Temporal lobe surgery in Germany from 1988 to 2008: diverse trends in etiological subgroups

BACKGROUND AND PURPOSE

In the epilepsy community, there is talk that the number of classical patients with early onset temporal lobe epilepsy (TLE) and Ammon's horn sclerosis (AHS) is decreasing. This is counterintuitive, considering the success story of epilepsy surgery, improved diagnostic methods and the current recommendation of early admission to surgery. In order to recognize trends, the development of temporal lobe surgery over 20 years in three major German epilepsy centers was reviewed.

METHODS

Age at surgery and duration of epilepsy, which was differentiated according to histopathology (AHS, developmental, tumor, vascular), year of surgery and center, were evaluated in a cohort of 2812 patients from three German epilepsy centers who underwent temporal lobe surgery between 1988 and 2008. The analysis was carried out for the pooled cohort as well as for each center separately.

RESULTS

Of all patients, 52% showed AHS. Compared with other pathologies, the AHS group had the earliest epilepsy onset and the longest duration of epilepsy. Across five time epochs, the diagnosis of AHS increased in the first epoch, remaining constant thereafter. Contrary to the trends in other pathologies, in the AHS group the mean age of patients at surgery increased by 7 years and the duration of epilepsy until surgery increased by 5 years. This trend could be replicated in all three centers. As initially hypothesized for all groups, age and duration of epilepsy in other pathology groups remained constant or indicated earlier submission to surgery.

CONCLUSIONS

During the first few years studied, most probably due to progress in brain imaging, the proportion of patients with AHS increased. However, despite stable numbers over time, and contrary to the trends in other pathology groups, age and duration of epilepsy in mesial TLE with AHS (mTLE + AHS) increased over time. This supports the hypothesis of a decreasing incidence of AHS. This trend is discussed with respect to disease-modifying factors which have changed the incidence of classical mTLE + AHS or, alternatively, to recent developments in antiepileptic drug treatment, the appraisal of surgery and economic incentives for treatment options other than surgery.

Disparities in access to specialized epilepsy care

OBJECTIVE

To examine the impact of individual and community characteristics on access to specialized epilepsy care.

METHODS

This retrospective cross-sectional study analyzed data from the California State Inpatient Sample, the State Ambulatory Surgery Database, and the State Emergency Department Database, that were linked with the 2009 Area Resource File and the location of the National Association of Epilepsy Center's epilepsy centers. The receipt of video-EEG monitoring was measured and used to indicate access to specialized epilepsy care in subjects with persistent seizures, identified as those who had frequent seizure-related hospital admissions and/or ER visits. A hierarchical logistic regression model was employed to assess barriers to high quality care at both individual and contextual levels.

RESULTS

Among 115,632 persons with persistent seizures, individuals who routinely received care in an area where epilepsy centers were located were more likely to have access to specialized epilepsy care (OR: 1.81, 95% CI: 1.20, 2.72). Interestingly, the availability of epilepsy centers did not influence access to specialized epilepsy care in people who had private insurance. In contrast, uninsured individuals and those with public insurance programs including Medicaid and Medicare had significant gaps in access to specialized epilepsy care. Other individual characteristics such as age, race/ethnicity, and the presence of comorbid conditions were also associated with disparities in access to specialized care in PWE.

CONCLUSION

Both individual and community characteristics play substantial roles in access to high quality epilepsy care. Policy interventions that incorporate strategies to address disparities at both levels are necessary to improve access to specialized care for PWE.

Current management and surgical outcomes of medically intractable epilepsy

Epilepsy is one of the most common neurologic disorders in the world. While anti-epileptic drugs (AEDs) are the mainstay of treatment in most cases, as many as one-third of patients will have a refractory form of disease indicating the need for a neurosurgical evaluation. Ever since the first half of the twentieth century, surgery has been a major treatment option for epilepsy, but the last 10-15 years in particular has seen several major advances. As shown in relatively recent studies, resection is more effective for medically intractable epilepsy (MIE) than AED treatment alone, which is why most clinicians now endorse a neurosurgical consultation after approximately two failed regimens of AEDs, ultimately leading to decreased healthcare costs and increased quality of life. Temporal lobe epilepsy (TLE) is the most common form of MIE and comprises about 80% of epilepsy surgeries with the majority of patients gaining complete seizure-freedom. As the number of procedures and different approaches continues to grow, temporal lobectomy remains consistently focused on resection of mesial structures such as the amygdala, hippocampus, and parahippocampal gyrus while preserving as much of the neocortex as possible resulting in optimum seizure control with minimal neurological deficits. MIE originating outside the temporal lobe is also effectively treated with resection. Though not as successful as TLE surgery because of their frequent proximity to eloquent brain structures and more diffuse pathology, epileptogenic foci located extratemporally also benefit from resection. Favorable seizure outcome in each of these procedures has heavily relied on pre-operative imaging, especially since the massive surge in MRI technology just over 20 years ago. However, in the absence of visible lesions on MRI, recent improvements in secondary imaging modalities such as fluorodeoxyglucose positron emission computed tomography (FDG-PET) and single-photon emission computed tomography (SPECT) have lead to progressively better long-term seizure outcomes by increasing the neurosurgeon's visualization of supposed non-lesional foci. Additionally, being historically viewed as a drastic surgical intervention for MIE, hemispherectomy has been extensively used quite successfully for diffuse epilepsies often found in pediatric patients. Although total anatomic hemispherectomy is not utilized as commonly today, it has given rise to current disconnective techniques such as hemispherotomy. Therefore, severe forms of hemispheric developmental epilepsy can now be surgically treated while substantially decreasing the amount of potential long-term complications resulting from cavitation of the brain following anatomical hemispherectomy. Despite the rapid pace at which we are gaining further knowledge about epilepsy and its surgical treatment, there remains a sizeable underutilization of such procedures. By reviewing the recent literature on resective treatment of MIE, we provide a recent up-date on epilepsy surgery while focusing on historical perspectives, techniques, prognostic indicators, outcomes, and complications associated with several different types of procedures.

Acceptance of epilepsy surgery in the pediatric age - what the parents think and what the doctors can do

Epilepsy surgery (ES) in pediatrics is safe and effective but can be underutilized. Possible barriers could be parental resistance and doctor inertia. We surveyed 138 parents of pediatric patients with epilepsy and found that 25.2% were opposed to this treatment. However, upon completing the questionnaire that contained factual information about ES, 50.4% of the responders stated that they had become more favorable vs. 3.3% more contrary and 46.3% unchanged. Parents of prepubescent patients were most receptive (p=0.0343) and more likely to shift to a more favorable attitude. Thus, pediatric neurologists should not hesitate to discuss ES as soon as indicated, providing all necessary information to increase acceptance. However, among 60 child neurologists surveyed, 60% did not fully comply with guidelines or follow accepted standards of practice, indicating that they may not be apt to provide proper parental guidance. We conclude that education of both practicing neurologists and parents is needed to facilitate the process.

Why is there still doubt to cut it out?

Surgical treatment for epilepsy has made tremendous strides in the past few decades as a result of advances in neurodiagnostics-particularly structural and functional neuroimaging-and improved surgical techniques. This has not only resulted in better outcomes with respect to epileptic seizures and quality of life, and reduced surgical morbidity and mortality, but it has also increased the population of patients now considered as surgical candidates, particularly in the pediatric age range, and enhanced cost-effectiveness sufficient to make surgical treatment available to countries with limited resources. Yet surgical treatment for epilepsy remains arguably the most underutilized of all accepted medical interventions. In the United States, less than 1% of patients with pharmacoresistant epilepsy are referred to epilepsy centers. Although the number of epilepsy surgery centers has increased appreciably over the past two decades, the number of therapeutic surgical procedures performed for epilepsy has not increased at all. For patients who are referred, the average delay from onset of epilepsy to surgery is more than 20 years-too late for many to avoid a lifetime of disability or premature death. Not only has there been no consistent message to convince neurologists and primary care physicians to refer patients for surgery, but the increase in epilepsy surgery centers in the United States has appeared to result in a divergence of approaches to surgical treatment. Efforts are still needed to further improve the safety and efficacy of surgical treatment, including the identification of biomarkers that can reliably determine the extent of the epileptogenic region; however, the greatest benefits would derive from increasing access for potential surgical candidates to epilepsy surgery facilities. Information is needed to determine why appropriate surgical referrals are not being made. Consensus conferences are necessary to resolve controversies that still exist regarding presurgical evaluation and surgical approaches. Standards should be established for certifying epilepsy centers as recommended by the Institute of Medicine's report on epilepsy. Finally, the epilepsy community should not be promoting epilepsy surgery per se but instead emphasize that epilepsy centers do more than epilepsy surgery, promoting the message: All patients with disabling pharmacoresistant seizures deserve evaluation by specialists at epilepsy centers who can provide a variety of advanced diagnostic and therapeutic services.