The safety of treating newly diagnosed epilepsy

Prevalence and nature of patient-reported antiseizure medication side effects in a Swedish regional multi-center study

PURPOSE

Side effects is one of the major clinical problems in epilepsy care. We assessed the prevalence of ASM side effects in participants in a large regional multicenter observational study in western Sweden and aimed to identify risk factors and inventory the nature of side effects with different ASM regimes.

METHODS

Cross-sectional analysis of survey answers and clinical characteristics of 406 adult participants recruited to a regional observational study between December 2020 and March 2023. Half of the participants had been seizure free for one year. Second-generation or newer ASMs were the most common.

RESULTS

A total of 164 (40 %, 95 %CI: 36-45) patients reported side effects. Patients reporting side effects were younger (median 41 vs 47 years, p = 0.015), had more frequently experienced a seizure in the last year (p = 0.02), and were more often on ASM polytherapy (p < 0.01). ASM polytherapy and age were significant risk factors in regression models, but the explanatory value was low. The most common side effect was tiredness followed by cognitive symptoms.

CONCLUSIONS

Our findings show that side effects are still common in epilepsy care and suggests that unnecessary polypharmacy should be avoided. Apart from number or ASMs, predicting who will experience side effects is difficult and more research on individual vulnerability is needed.

Seizures in the Emergency Department: clinical and diagnostic data from a series of 153 patients

INTRODUCTION

Seizures are a frequent reason for admission to emergency departments and require early, precise diagnosis and treatment. The objective of this study was to describe the clinical and prognostic characteristics of a series of patients with seizures attended at our hospital's emergency department.

METHODS

We performed a retrospective, observational study of all patients with seizures who were admitted to our hospital's emergency department and attended by the on-call neurology service between February and August 2017.

RESULTS

We included 153 patients, representing 9.9% of all neurological emergency department admissions. The median age was 58 years, 52.3% of patients were women, and 51% had history of epilepsy. Onset was focal in 82.4% of cases, and the most frequent aetiology was cerebrovascular disease (24.2%). Twelve patients (7.8%) developed status epilepticus, which was associated with higher scores on the ADAN scale (P < .001) and with history of refractory epilepsy (P = .002). The in-hospital mortality rate was 3.7%, and in-hospital mortality was associated with older age (P = .049) and status epilepticus (P = .018). Eighty percent of patients with no history of epilepsy were diagnosed with epilepsy at the emergency department; all started treatment. The kappa coefficient for epilepsy diagnosis in the emergency department compared to diagnosis after one year of follow-up by the epilepsy unit was 0.45 (diagnosis was modified in 20% of patients).

CONCLUSIONS

Seizures are a frequent neurological emergency with potential complications and considerable morbidity and mortality rates. In patients with no known history of epilepsy, the condition may be diagnosed in the emergency department, but follow-up at specialised epilepsy units is recommended.

Bidirectionality of antiseizure and antipsychotic treatment: A population-based study

PURPOSE

To study the prevalence and directionality of comorbid epilepsy and psychosis in Norway.

METHODS

The Norwegian Prescription Database (NorPD) provided individual-based information on all antiseizure medications (ASMs) and antipsychotic drugs (APDs) dispensed during 2004-2017. Subjects were ≥18 years of age at the end of the study period. Diagnosis-specific reimbursement codes from the 10th revision of the International Classification of Diseases/2nd edition of the International Classification of Primary Care (ICD-10/ICPC-2) combined with ATC codes were used as indicators of diagnosis. Subjects had collected ASMs for epilepsy or APDs for psychosis at least four times, at least once issued with an ICD-10 code from the specialist healthcare service. Directionality was analyzed in subjects receiving both treatments. To reduce prevalent comorbidity bias, we employed a four-year comorbidity-free period (2004-2007). The use of specific ASMs and APDs was analyzed.

RESULTS

A total of 31,289 subjects had collected an ASM for epilepsy at least four times, 28,889 an APD for psychosis. Both the prevalence of treatment for epilepsy and of treatment for psychosis was 0.8%. Further, 891 subjects had been treated for both conditions; 2.8% with epilepsy had been treated for psychosis, and 3.1% with psychosis had been treated for epilepsy. Among 558 subjects included in the analyses of directionality, 56% had collected the first APD before an ASM, whereas 41% had collected an ASM first. During the last year prior to comorbidity onset, levetiracetam, topiramate, or zonisamide had been used for epilepsy by approximately 40%, whereas olanzapine and quetiapine were most used in patients with psychosis, and clozapine in 13%.

CONCLUSION

The proportion of patients with prior antipsychotic treatment at onset of epilepsy is higher than previously acknowledged, as demonstrated in this nation-wide study. Apart from a shared neurobiological susceptibility, the bidirectionality of epilepsy and psychosis may be influenced by various environmental factors, including the interaction of pharmacodynamic effects. APDs may facilitate seizures; ASMs may induce psychiatric symptoms. In patients with combined treatment, these potential drug effects should receive ample attention, along with the psychosocial consequences of the disorders. A prudent multi-professional approach is required.

Risk factors and consequences of self-discontinuation of treatment by patients with newly diagnosed epilepsy

OBJECTIVE

Patients with epilepsy not uncommonly self-discontinue treatment with antiseizure medications (ASM). The rate, reasons for this, and consequences have not been well studied.

METHODS

We analyzed self-discontinuation of ASM treatment in patients with recently diagnosed epilepsy via review of clinic letters and hospital correspondence in a prospective cohort of first seizure patients.

RESULTS

We studied 489 patients with newly diagnosed and treated epilepsy (median age 41, range 14-88, 62% male), followed up for a median duration of 3.0 years (interquartile range [IQR]: 1.2-6.0). Seventy eight (16.0%) self-discontinued ASM therapy after a median treatment duration of 1.4 years (IQR: 0.4-2.9), and after a median duration of seizure freedom of 11.8 months (IQR: 4.6-31.8). Patients commonly self-discontinued treatment due to adverse effects (41%), perception that treatment was no longer required (35%), and planned or current pregnancy (12%). Patients who self-discontinued were less likely to have epileptogenic lesions on neuroimaging (hazard ratio [HR] = 0.44, 95% confidence interval [CI]: 0.23-0.83), presentation with seizure clusters (HR = 0.32, 95% CI: 0.14-0.69) and presentation with tonic-clonic seizures (HR = 0.36, 95% CI: 0.19-0.70). Patients with shorter interval since the last seizure (HR = 0.76, 95% CI: 0.66-0.86) were more likely to self-discontinue treatment. Sleep deprivation prior to seizures before diagnosis (HR = 1.80, 95% CI: 1.05-3.09) and significant alcohol or illicit drug use (HR = 2.35, 95% CI: 1.20-4.59) were also associated with higher rates of discontinuation. After discontinuation, 51 patients (65%) experienced seizure recurrence, and 43 (84%) restarted treatment. Twenty two patients (28%) experienced a seizure-related injury after treatment discontinuation.

SIGNIFICANCE

Self-initiated discontinuation of ASM treatment was not uncommon in patients with newly treated epilepsy. Reasons for discontinuation highlight areas for improved discussion with patients, including the chronicity of epilepsy and management strategies for current or potential adverse effects.

Potential role of regulatory DNA variants in modifying the risk of severe cutaneous reactions induced by aromatic anti-seizure medications

Objective

Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse drug reactions. Antiseizure medications (ASMs) with aromatic ring structure, including carbamazepine, are among the most common culprits. Screening for human leukocyte antigen (HLA) allele HLA‐B*15:02 is recommended prior to initiating treatment with carbamazepine in Asians, but this allele has low positive predictive value.

Methods

We performed whole genome sequencing and analyzed 6 199 696 common variants among 113 aromatic ASM‐induced SJS/TEN cases and 84 tolerant controls of Han Chinese ethnicity.

Results

In the primary analysis, nine variants reached genome‐wide significance (p < 5e‐08), one in the carbamazepine subanalysis (85 cases vs. 77 controls) and a further eight identified in HLA‐B*15:02‐negative subanalysis (35 cases and 53 controls). Interaction analysis between each novel variant from the primary analysis found that five increased risk irrespective of HLA‐B*15:02 status or zygosity. HLA‐B*15:02‐positive individuals were found to have reduced risk if they also carried a chromosome 12 variant, chr12.9426934 (heterozygotes: relative risk = .71, p = .001; homozygotes: relative risk = .23, p < .001). All significant variants lie within intronic or intergenic regions with poorly understood functional consequence. In silico functional analysis of suggestive variants (p < 5e‐6) identified through the primary and subanalyses (stratified by HLA‐B*15:02 status and drug exposure) suggests that genetic variation within regulatory DNA may contribute to risk indirectly by disrupting the regulation of pathology‐related genes. The genes implicated were specific either to the primary analysis (CD9), HLA‐B*15:02 carriers (DOCK10), noncarriers (ABCA1), carbamazepine exposure (HLA‐E), or phenytoin exposure (CD24).

Significance

We identified variants that could explain why some carriers of HLA‐B*15:02 tolerate treatment, and why some noncarriers develop ASM‐induced SJS/TEN. Additionally, this analysis suggests that the mixing of HLA‐B*15:02 carrier status in previous studies might have masked variants contributing to susceptibility, and that inheritance of risk for ASM‐induced SJS/TEN is complex, likely involving multiple risk variants.

Short- and long-term outcomes of immediate and delayed treatment in epilepsy diagnosed after one or multiple seizures

OBJECTIVES

To compare the outcomes between immediate and deferred treatments in patients diagnosed after one or multiple (two or more) seizures.

METHODS

Our observational study investigated seizure recurrence and 12-month seizure remission in patients with newly diagnosed epilepsy, comparing immediate to deferred treatment in patients diagnosed after one seizure or after two or more seizures.

RESULTS

Of 598 patients (62% male, median age 39 years), 347 (58%) were treated at diagnosis and 251 (42%) received deferred or no treatment. Seizure recurrence was higher with deferred treatment both in patients diagnosed after two or more seizures (n = 363; adjusted hazard ratio [aHR] = 2.38, 95% confidence interval [CI]: 1.79-3.14, p < 0.001) and after one seizure (n = 235; aHR = 1.41, 95% CI: 0.995-1.99, p = 0.05). Cumulative seizure recurrence rates at two years in patients diagnosed after two or more seizures were 73% with deferred treatment and 49% with immediate treatment (risk-factor-corrected number-needed-to-treat [NNT] = 4), and in those diagnosed after one seizure the rates were 60% and 51% (NNT = 8). Of 380 patients with eligible follow-up (median 4.3 years), 287 (76%) had been in seizure remission for at least one year and 211 (56%) remained in remission at last follow-up. Long-term remission rates were similar between immediate and deferred treatments, and between patients diagnosed after one seizure and those with two or more seizures.

SIGNIFICANCE

Immediate rather than deferred treatment was less likely to influence seizure recurrence in patients diagnosed with epilepsy after a single seizure than in those diagnosed after two or more seizures, and showed no differences in long-term seizure freedom.

The Implementation Science for Genomic Health Translation (INSIGHT) Study in Epilepsy: Protocol for a Learning Health Care System

BACKGROUND

Genomic medicine is poised to improve care for common complex diseases such as epilepsy, but additional clinical informatics and implementation science research is needed for it to become a part of the standard of care. Epilepsy is an exemplary complex neurological disorder for which DNA diagnostics have shown to be advantageous for patient care.

OBJECTIVE

We designed the Implementation Science for Genomic Health Translation (INSIGHT) study to leverage the fact that both the clinic and testing laboratory control the development and customization of their respective electronic health records and clinical reporting platforms. Through INSIGHT, we can rapidly prototype and benchmark novel approaches to incorporating clinical genomics into patient care. Of particular interest are clinical decision support tools that take advantage of domain knowledge from clinical genomics and can be rapidly adjusted based on feedback from clinicians.

METHODS

Building on previously developed evidence and infrastructure components, our model includes the following: establishment of an intervention-ready genomic knowledge base for patient care, creation of a health informatics platform and linking it to a clinical genomics reporting system, and scaling and evaluation of INSIGHT following established implementation science principles.

RESULTS

INSIGHT was approved by the Institutional Review Board at the University of Texas Health Science Center at Houston on May 15, 2020, and is designed as a 2-year proof-of-concept study beginning in December 2021. By design, 120 patients from the Texas Comprehensive Epilepsy Program are to be enrolled to test the INSIGHT workflow. Initial results are expected in the first half of 2023.

CONCLUSIONS

INSIGHT's domain-specific, practical but generalizable approach may help catalyze a pathway to accelerate translation of genomic knowledge into impactful interventions in patient care.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/25576.

Tolerability of Antiseizure Medications in Individuals With Newly Diagnosed Epilepsy

Importance

Tolerability is a key determinant of the effectiveness of epilepsy treatment. It is important to evaluate whether the overall tolerability has improved.

Objective

To identify factors associated with poor tolerability of antiseizure medications (ASMs) and examine temporal changes in tolerability.

Design, Setting, and Participants

This was a longitudinal cohort study at a specialist clinic in Glasgow, Scotland. Patients with newly diagnosed and treated epilepsy between July 1982 and October 2012 were included from 2282 eligible individuals. They were followed up until April 2016 or death. Data analysis was completed in August 2019.

Exposures

Antiseizure medications.

Main Outcomes and Measures

Univariable and multivariable survival analyses were performed to examine associations between potential risk factors and development of intolerable adverse effects (AEs). Intolerable AE rates of the ASMs as the initial monotherapy were compared between 3 epochs (July 1982-June 1992, July 1992-June 2002, and July 2002-April 2016).

Results

Of 1795 patients, 969 (54.0%) were male, and the median (interquartile range) age was 33 (21-50) years. A total of 3241 ASMs were prescribed during the period, of which 504 (15.6%) were discontinued within 6 months owing to intolerable AEs. Children younger than 18 years had lower intolerable AE rates than adults (vs aged 18-64 years: adjusted hazard ratio [aHR], 1.58; 95% CI, 1.07-2.32; vs aged ≥65 years: aHR, 1.90; 95% CI, 1.19-3.02) while female individuals (aHR, 1.60; 95% CI, 1.30-1.96) and those who had more than 5 pretreatment seizures (aHR, 1.24; 95% CI, 1.03-1.49) were associated with having higher risk. For each ASM trial, the risk of intolerable AEs increased with the number of previous drug withdrawals due to AEs (aHR, 1.18; 95% CI, 1.09-1.28) and the number of concomitant ASMs (aHR, 1.31; 95% CI, 1.04-1.64). The proportion of second-generation ASMs prescribed as the initial monotherapy increased from 22.3% (33 of 148) in the first epoch to 68.7% (645 of 939) in the last (P < .001). Although differences in intolerable AE rates and types of AEs were found between the ASMs, there was no difference in the overall intolerable AEs rates to the initial monotherapy across the 3 epochs (first: 10.1% [15 of 148]; second: 13.8% [98 of 708]; third: 14.0% [131 of 939]; P = .41).

Conclusions and Relevance

In this cohort study, the increased use of the second-generation ASMs had not improved overall treatment tolerability. Greater effort to improve tolerability in ASM development is needed.

Seizures in the Emergency Department: Clinical and diagnostic data from a series of 153 patients

INTRODUCTION

Seizures are a frequent reason for admission to emergency departments and require early, precise diagnosis and treatment. The objective of this study was to describe the clinical and prognostic characteristics of a series of patients with seizures attended at our hospital's emergency department.

METHODS

We performed a retrospective, observational study of all patients with seizures who were admitted to our hospital's emergency department and attended by the on-call neurology service between February and August 2017.

RESULTS

We included 153 patients, representing 9.9% of all neurological emergency department admissions. The median age was 58 years, 52.3% of patients were women, and 51% had history of epilepsy. Onset was focal in 82.4% of cases, and the most frequent aetiology was cerebrovascular disease (24.2%). Twelve patients (7.8%) developed status epilepticus, which was associated with higher scores on the ADAN scale (P<.001) and with history of refractory epilepsy (P=.002). The in-hospital mortality rate was 3.7%, and in-hospital mortality was associated with older age (P=.049) and status epilepticus (P=.018). Eighty percent of patients with no history of epilepsy were diagnosed with epilepsy at the emergency department; all started treatment. The kappa coefficient for epilepsy diagnosis in the emergency department compared to diagnosis after one year of follow-up by the epilepsy unit was .45 (diagnosis was modified in 20% of patients).

CONCLUSIONS

Seizures are a frequent neurological emergency with potential complications and considerable morbidity and mortality rates. In patients with no known history of epilepsy, the condition may be diagnosed in the emergency department, but follow-up at specialised epilepsy units is recommended.