Dataset Information

Assessing the role of rare genetic variants in drug-resistant, non-lesional focal epilepsy.

ABSTRACT:

Objective

Resistance to antiseizure medications (ASMs) is one of the major concerns in the treatment of epilepsy. Despite the increasing number of ASMs available, the proportion of individuals with drug-resistant epilepsy remains unchanged. In this study, we aimed to investigate the role of rare genetic variants in ASM resistance.

Methods

We performed exome sequencing of 1,128 individuals with non-familial non-acquired focal epilepsy (NAFE) (762 non-responders, 366 responders) and were provided with 1,734 healthy controls. We undertook replication in a cohort of 350 individuals with NAFE (165 non-responders, 185 responders). We performed gene-based and gene-set-based kernel association tests to investigate potential enrichment of rare variants in relation to drug response status and to risk for NAFE.

Results

We found no gene or gene set that reached genome-wide significance. Yet, we identified several prospective candidate genes - among them DEPDC5, which showed a potential association with resistance to ASMs. We found some evidence for an enrichment of truncating variants in dominant familial NAFE genes in our cohort of non-familial NAFE and in association with drug-resistant NAFE.

Interpretation

Our study identifies potential candidate genes for ASM resistance. Our results corroborate the role of rare variants for non-familial NAFE and imply their involvement in drug-resistant epilepsy. Future large-scale genetic research studies are needed to substantiate these findings.

SUBMITTER: Wolking S

PROVIDER: S-EPMC8283173 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:ObjectiveTo gather real-world evidence on antiseizure medications (ASMs) treatment patterns and related outcomes in patients with drug-resistant focal epilepsy.MethodsMedical insurance claims from the start of 2014 till the end of 2019 were used. Patient selection criteria included International Classification of Diseases (ICD) codes followed by documented ASM use. Baseline patient demographics along with ASM and rescue medication use patterns and related patient outcome were documented for first (index) ASM regimen. Patients who failed the first regimen and then failed the second regimen were considered drug resistant. Multivariate analyses were performed to identify risks and other characteristics for positive or negative treatment outcomes.ResultsStudy cohort consisted of 46 474 patients with a mean age of 47.23 (SD: 16.94). Levetiracetam was the most first-encountered ASM (37.94%). At baseline, 87.14% were treated with ASMs prior to having study-confirmed diagnoses. Mental comorbidities were present in 37.86% of patients. After first-year ASM treatment, 34.61% of patients persisted on their index regimen and 5.91% were seizure-free. Patients failing first ASM regimen numbered 12 868 (27.69%). Drug-resistant patients who failed first and then second ASM regimens numbered 6335 (49.23%). Percentages of patients who had successful second treatment and seizure-free were 21.32 and 3.65, respectively. Initiating patients on lamotrigine or carbamazepine (relative to levetiracetam), baseline use of index ASM, rescue medications, and older age or male gender all lowered the risk for treatment failure. Having higher comorbidity, comorbid mental illness, headache, or neoplasty increased such a risk. Baseline use of index ASM, depressive episode, or anxiety disorder all entailed higher risk of failing second ASM treatment.SignificanceOverall, reported findings indicated that patient history at baseline and the early selection of an ASM all influenced treatment outcomes. Findings pointed to the complex nature of ASM treatment in drug-resistant focal epilepsy patients calling for additional research to identify the optimal treatment to achieve beneficial patient outcomes.