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

Increasing Risk of Dementia Among Patients with Subsequent Epilepsy Within 2 Years Post-Traumatic Brain Injury: A Population-Based Case-Control Study

Background

Although the association between neurodegenerative diseases, such as dementia, and traumatic brain injury (TBI) has long been known, the association between dementia and TBI with epilepsy has been controversial.

Aim

This data-driven population-based study is designed to investigate the association between dementia and epilepsy after TBI within a 2-year period.

Methods

This case-control cohort study was conducted using the Longitudinal Health Insurance Database 2000 (LHID2000). We included 784 individuals ambulatory or hospitalized for TBI with epilepsy from 2001 to 2011, compared with 2992 patients with TBI without epilepsy who were matched for characteristics including sex, age, and healthcare resource use index date. Every participant was followed up for 5 years to ascertain any dementia development. Data were stratified and analyzed using the Cox proportional hazards regression.

Results

Through the 5-year follow-up period, 39 patients (5.21%) with TBI with epilepsy and 55 (1.53%) with TBI without epilepsy developed dementia. TBI with epilepsy was independently associated with a >3.03 times risk of dementia after correcting for age, sex, and comorbidities.

Conclusion

These findings suggest an increased risk of dementia in patients with TBI with epilepsy. Our research recommends that individuals with TBI and epilepsy be monitored more intensively.

Development of a physiologically based pharmacokinetic model for levetiracetam in patients with renal impairment to guide dose adjustment based on steady-state peak/trough concentrations

Levetiracetam may cause acute renal failure and myoclonic encephalopathy at high plasma levels, particularly in patients with renal impairment. The aim of this study was to develop a physiologically based pharmacokinetic (PBPK) model to predict levetiracetam pharmacokinetics in Chinese adults with epilepsy and renal impairment and define appropriate levetiracetam dosing regimen.PBPK models for healthy subjects and epilepsy patients with renal impairment were developed, validated, and adapted. Furthermore, we predicted the steady-state trough and peak concentrations of levetiracetam in patients with renal impairment using the final PBPK model, thereby recommending appropriate levetiracetam dosing regimens for different renal function stages. The predicted maximum plasma concentration (Cmax), time to maximum concentration (Tmax), area under the plasma concentration-time curve (AUC) were in agreement (0.8 ≤ fold error ≤ 1.2) with the observed, and the fold error of the trough concentrations in end-stage renal disease (ESRD) was 0.77 - 1.22. The prediction simulations indicated that the recommended doses of 1000, 750, 500, and 500 mg twice daily for epilepsy patients with mild, moderate, severe renal impairment, and ESRD, respectively, were sufficient to achieve the target plasma concentration of levetiracetam.

Brain lesion locations associated with secondary seizure generalization in tumors and strokes

Structural brain lesions are the most common cause of adult-onset epilepsy. The lesion location may contribute to the risk for epileptogenesis, but whether specific lesion locations are associated with a risk for secondary seizure generalization from focal to bilateral tonic-clonic seizures, is unknown. We identified patients with a diagnosis of adult-onset epilepsy caused by an ischemic stroke or a tumor diagnosed at the Turku University Hospital in 2004-2017. Lesion locations were segmented on patient-specific MR imaging and transformed to a common brain atlas (MNI space). Both region-of-interest analyses (intersection with the cortex, hemisphere, and lobes) and voxel-wise analyses were conducted to identify the lesion locations associated with focal to bilateral tonic-clonic compared to focal seizures. We included 170 patients with lesion-induced epilepsy (94 tumors, 76 strokes). Lesions predominantly localized in the cerebral cortex (OR 2.50, 95% C.I. 1.21-5.15, p = .01) and right hemisphere (OR 2.22, 95% C.I. 1.17-4.20, p = .01) were independently associated with focal to bilateral tonic-clonic seizures. At the lobar-level, focal to bilateral tonic-clonic seizures were associated with lesions in the right frontal cortex (OR 4.41, 95% C.I. 1.44-13.5, p = .009). No single voxels were significantly associated with seizure type. These effects were independent of lesion etiology. Our results demonstrate that lesion location is associated with the risk for secondary generalization of epileptic seizures. These findings may contribute to identifying patients at risk for focal to bilateral tonic-clonic seizures.

Prescription trends in anti-seizure medications for adult patients with epilepsy in Japan: A retrospective cohort study using the database of health insurance claims between 2015 and 2019

OBJECTIVE

To investigate whether newer anti-seizure medications (ASMs) are widely prescribed for a range of adult patients in Japan, including patients with previously and newly diagnosed epilepsy, or with focal and generalized epilepsies.

METHODS

A retrospective cohort study was conducted using the Japanese insurance claims database including 8.4 million people to identify adults (≥16 years of age) with epilepsy diagnosis code identified between January 2015 and December 2018. Patients were included in the prevalent population if epilepsy was already diagnosed at baseline, and in the incident population if prior baseline data for at least 12 months included no epilepsy diagnosis code or ASM prescription. Patients were followed up from the month when the initial oral ASM was prescribed for up to 4 years until the end of 2019 as long as at least one ASM was prescribed. Proportions of prescribed oral ASMs were analyzed by population with epilepsy (prevalent vs. incident) and classification (focal vs. generalized). Anti-seizure medications were classified into older vs. newer ASMs according to the date of approval before and after 1990, respectively.

RESULTS

A total of 24,691 patients fulfilled the eligibility criteria for the analysis. Of these, 21,046 and 3,645 were included in the prevalent and incident populations, respectively. The proportion of older ASMs significantly decreased, whereas the proportion of newer ASMs significantly increased (p < 0.0001) during the study period. This trend was more apparent in the population with incident epilepsy than in that with prevalent epilepsy, and was also apparent in the subgroup of focal epilepsy, but not in that of generalized epilepsy. Levetiracetam was the most frequently prescribed of the newer ASMs.

CONCLUSION

Newer ASMs became more widely prescribed throughout the study period in populations with both prevalent and incident epilepsies, as well as the subpopulation with focal epilepsy. The advantages of newer ASMs such as better safety profiles may have led to the increasing proportions of prescriptions and newer ASMs may increase the treatment options for patients.

Incidence of Acute Renal Failure in Patients Using Levetiracetam Versus Other Antiseizure Medications: A Voluntary Post-Authorization Safety Study

INTRODUCTION

Acute kidney injury is an expected adverse drug reaction listed in the European Union (EU) Summary of Product Characteristics (SmPC) for levetiracetam, one of the most widely used modern antiseizure medications (ASMs).

OBJECTIVE

We conducted a voluntary post-authorization safety study to characterize the rate of acute renal failure (ARF) in patients exposed to levetiracetam versus other ASMs.

METHODS

New users of ASMs without prior renal dysfunction were identified and followed for 30 days in the IBM^® MarketScan^® database (USA, January 2008-December 2017). ARF was defined as a diagnosis on inpatient or emergency department claims. We estimated adjusted incidence rates, incidence rate ratios (IRRs), and incidence rate differences (IRDs) of ARF in patients initiating levetiracetam versus other ASMs.

RESULTS

Overall, 110,336 patients were eligible for the monotherapy cohort and 96,215 were eligible for the polytherapy cohort. The overall crude rate of ARF following a new ASM was 6.0 and 6.5 per 10,000 patients for the 'monotherapy' and 'polytherapy' cohorts, respectively, in the first 30 days after the index date. In the monotherapy cohort, the IRR for ARF was 1.37 (95% confidence interval [CI] 0.80-2.34) and the corresponding IRD was 2.0 (95% CI - 1.12 to 5.12) additional ARFs per 10,000 patient-months. In the polytherapy cohort, the adjusted IRR for ARF was 0.94 (95% CI 0.51-1.74) and the corresponding IRD was - 0.42 cases per 10,000 patient-months (95% CI - 4.01 to 3.17).

CONCLUSIONS

The rate of ARFs in ASM new users was very low. In patients without prior ASMs, the estimated difference in risk of ARF associated with initiation of levetiracetam versus initiation of other ASMs was small, with 95% CIs compatible with small protective or harmful effects. In patients receiving polytherapy, the difference was compatible with the null and the 95% CI with small protective or harmful effects.

Severity of Epilepsy and Response to Antiseizure Medications in Individuals with Multiple Sclerosis: Analysis of a Real-World Dataset

Background and objectives:

Epilepsy is an important comorbidity that affects outcomes for people with multiple sclerosis (MS). However, it is unclear if seizure severity among individuals with coexistence of multiple sclerosis and epilepsy (MS+E) is higher than in those with other focal epilepsies. Our goal was to compare the overall severity of epilepsy in individuals with MS+E versus those with focal epilepsy without MS (E-MS) as defined by seizure-related healthcare utilization, frequency and duration of status epilepticus, and frequency of antiseizure medication (ASM) regimen changes.

Methods:

In this hypothesis-generating study, we analyzed a U.S. commercial nationwide de-identified claims dataset with > 86 million individuals between 1/1/2008 and 8/31/2019. Using validated algorithms, we identified adults with E-MS and those with MS+E. We compared the number and length of seizure-related hospital admissions, the number of claims and unique days with claims for status epilepticus, and the rates of ASM regimen changes between the MS+E and the E-MS groups.

Results:

During the study period, 66,708 individuals with E-MS and 537 with MS+E had ≥ 2 years of coverage after their initial diagnosis of epilepsy. There was no difference between the MS+E and E-MS groups in the percentage of individuals admitted for seizures and/or status epilepticus. However, MS+E with seizure-related admissions had more admissions and longer hospital stays than those with E-MS. MS+E who experienced status epilepticus had more unique days with status epilepticus claims compared to E-MS. MS+E were more likely to have ASM regimen changes in Year 2 after the initial diagnosis of epilepsy and had more ASM changes during Year 2 compared to E-MS. Among individuals with MS+E, there were no differences in our measures of seizure severity for those treated with sodium channel blockers/modulators versus other ASM classes.

Discussion:

This study supports the notion that individuals with MS+E can have more severe epilepsy than those with E-MS. Seizure severity among individuals with MS+E treated with sodium-channel blockers/modulators versus other ASM classes shows no significant differences.

Classification of evidence:

This study provides Class III evidence that individuals with MS+E can have more severe epilepsy than those with E-MS.