Valproate impact and sex-dependent seizure remission in patients with idiopathic generalized epilepsy

Oligoepilepsy and lifelong seizure susceptibility in epilepsy with generalized tonic-clonic seizures alone: Experience at an adult tertiary center

OBJECTIVE

Epilepsy with generalized tonic-clonic seizures alone (GTCA) is the least studied syndrome within the idiopathic generalized epilepsy (IGE) spectrum. We characterize a large cohort of adult patients with GTCA to understand natural history and drug responsiveness.

METHODS

In this retrospective single-center study using our epilepsy electronic record, we evaluated clinical characteristics, seizure outcomes, anti-seizure medication (ASM) response including seizure recurrence after ASM withdrawal, and sex differences in a cohort of GTCA patients aged ≥17 years.

RESULTS

Within a cohort of 434 IGE patients, 87 patients (20 %) with GTCA were included. The mean age was 34.9 years (range 17-73 years). Forty-six patients (52.8 %) were females. Seventy-two patients (82.8 %) were seizure-free and 15 (17.2 %) had active epilepsy over the previous 12 months. Thirty-four patients (39.1 %) had ≤5 lifetime seizures, aligning with a prior definition of 'oligoepilepsy'. Sixty-five patients (74.7 %) were treated with monotherapy, 19 (21.8 %) were treated with polytherapy, and three were not taking any ASM. Levetiracetam (37.9 %) was the most commonly prescribed ASM, followed by lamotrigine (32.1 %) and valproate (31 %). Seventeen patients (19.5 %) attempted to withdraw their ASM. The rate of seizure recurrence after ASM withdrawal was 88.2 % (15/17), including two patients who relapsed more than 20 years after ASM discontinuation. Females had more seizures in their lifetime and had trialed more ASM compared to males.

SIGNIFICANCE

GTCA has a relatively good prognosis, with most patients becoming seizure-free on monotherapy. The high rate of seizure recurrence after ASM withdrawal supports lifetime seizure susceptibility. We found potential sex differences in seizure outcomes and ASM response, although further research is needed to validate this finding.

Predictors of Seizure Recurrence in Women With Idiopathic Generalized Epilepsy Who Switch From Valproate to Another Medication

BACKGROUND AND OBJECTIVES

To investigate the predictors of seizure recurrence in women of childbearing age with idiopathic generalized epilepsy (IGE) who switched from valproate (VPA) to alternative antiseizure medications (ASMs) and compare the effectiveness of levetiracetam (LEV) and lamotrigine (LTG) as VPA alternatives after switch.

METHODS

This multicenter retrospective study included women of childbearing age diagnosed with IGE from 16 epilepsy centers. Study outcomes included worsening or recurrence of generalized tonic-clonic seizure (GTCS) at 12 months and 24 months after the switch from VPA to an alternative ASM. The comparative effectiveness of LEV and LTG as alternative ASM following VPA discontinuation was assessed through inverse probability treatment-weighted (IPTW) Cox regression analysis.

RESULTS

We included 426 women with IGE, with a median (interquartile range) age at VPA switch of 24 (19-30) years and a median VPA dosage of 750 (500-1,000) mg/d. The most common reason for VPA switch was teratogenicity concern in 249 women (58.6%), and the most common ASM used in place of VPA was LEV in 197 (46.2%) cases, followed by LTG in 140 (32.9%). GTCS worsening/recurrence occurred in 105 (24.6%) and 139 (32.6%) women at 12 and 24 months, respectively. Catamenial worsening of seizures, higher VPA dosage during switch, multiple seizure types, and shorter duration of GTCS freedom before switch were independent predictors of GTCS recurrence or worsening at 12 months according to mixed multivariable logistic regression analysis. After internal-external validation through 16 independent cohorts, the model showed an area under the curve of 0.71 (95% CI 0.64-0.77). In the subgroup of 337 women who switched to LEV or LTG, IPTW Cox regression analysis showed that LEV was associated with a reduced risk of GTCS worsening or recurrence compared with LTG (adjusted hazard ratio 0.59, 95% CI 0.40-0.87, p = 0.008) during the 24-month follow-up.

DISCUSSION

Our findings can have practical implications for optimizing counselling and treatment choices in women of childbearing age with IGE and may help clinicians in making informed treatment decisions in this special population of patients.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for women with IGE switching from VPA, LEV was associated with a reduced risk of GTCS worsening or recurrence compared with LTG.

Topiramate ban in women of childbearing potential with idiopathic generalized epilepsy: Does effectiveness offset the teratogenic risks?

Regulatory agencies have recently discouraged the prescription of topiramate (TPM) to women of childbearing potential with epilepsy due to growing evidence of the teratogenic and neurodevelopmental risks associated with its use during pregnancy. It remains, however, unclear whether the use of TPM in this population can be supported to some extent by its high effectiveness. In this multicenter, retrospective, cohort study performed at 22 epilepsy centers, we investigated the comparative effectiveness of TPM and levetiracetam (LEV) given as first-line antiseizure medication in a cohort of women of childbearing potential with idiopathic generalized epilepsy (IGE). A total of 336 participants were included, of whom 24 (7.1%) received TPM and 312 (92.9%) LEV. Women treated with TPM had significantly higher risks of treatment failure and treatment withdrawal and were less likely to achieve seizure freedom at 12 months compared to women treated with LEV. In conclusion, this study highlighted a low tendency among clinicians to use TPM in women of childbearing potential with IGE, anticipating the recently released restrictions on its use. Furthermore, the available data on effectiveness do not appear to support the use of TPM in this population.

Levetiracetam vs Lamotrigine as First-Line Antiseizure Medication in Female Patients With Idiopathic Generalized Epilepsy

Importance

After the recent limitations to prescribing valproate, many studies have highlighted the challenging management of female patients of reproductive age with idiopathic generalized epilepsy (IGE). However, no study, to the authors' knowledge, has addressed the comparative effectiveness of alternative antiseizure medications (ASMs) in these patients.

Objective

To compare the effectiveness and safety of levetiracetam and lamotrigine as initial monotherapy in female patients of childbearing age with IGE.

Design, Setting, and Participants

This was a multicenter, retrospective, comparative effectiveness cohort study analyzing data from patients followed up from 1994 to 2022. Patients were recruited from 22 primary, secondary, and tertiary adult and child epilepsy centers from 4 countries. Eligible patients were female individuals of childbearing age, diagnosed with IGE according to International League Against Epilepsy (2022) criteria and who initiated levetiracetam or lamotrigine as initial monotherapy. Patients were excluded due to insufficient follow-up after ASM prescription.

Exposures

Levetiracetam or lamotrigine as initial monotherapy.

Main Outcomes and Measures

Inverse probability of treatment weighting (IPTW)-adjusted Cox proportional hazards regression was performed to compare treatment failure (TF) among patients who received levetiracetam or lamotrigine as initial monotherapy.

Results

A total of 543 patients were included in the study, with a median (IQR) age at ASM prescription of 17 (15-21) years and a median (IQR) follow-up of 60 (24-108) months. Of the study population, 312 patients (57.5%) were prescribed levetiracetam, and 231 (42.5%) were prescribed lamotrigine. An IPTW-adjusted Cox model showed that levetiracetam was associated with a reduced risk of treatment failure after adjustment for all baseline variables (IPTW-adjusted hazard ratio [HR], 0.77; 95% CI, 0.59-0.99; P = .04). However, after stratification according to different IGE syndromes, the higher effectiveness of levetiracetam was confirmed only in patients with juvenile myoclonic epilepsy (JME; IPTW-adjusted HR, 0.47; 95% CI, 0.32-0.68; P < .001), whereas no significant differences were found in other syndromes. Patients treated with levetiracetam experienced adverse effects more frequently compared with those treated with lamotrigine (88 of 312 [28.2%] vs 42 of 231 [18.1%]), whereas the 2 ASMs had similar retention rates during follow-up (IPTW-adjusted HR, 0.91; 95% CI, 0.65-1.23; P = .60).

Conclusions and Relevance

Results of this comparative effectiveness research study suggest the use of levetiracetam as initial alternative monotherapy in female patients with JME. Further studies are needed to identify the most effective ASM alternative in other IGE syndromes.

Optimizing treatment persistence in epilepsy: a comparative analysis of combined antiseizure medications with different mechanisms of action

Background

Combination therapy with antiseizure medications (ASMs) is a rational strategy if monotherapy cannot effectively control seizures, thereby aiming to improve tolerance and treatment persistence.

Objectives

To compare the efficacy of different ASM combinations among patients.

Design

Patients with epilepsy on monotherapy who had a second ASM added as concomitant two-drug therapy from January 2009 to May 2019 in the Chang Gung Research Database, Taiwan, were included in the analysis.

Methods

ASM combinations were compared based on their primary mechanism of action (MoA) which are as follows: gamma-aminobutyric acid receptor (G), sodium channel blocker (SC), synaptic vesicle protein 2A (SV2), calcium channel blocker (C), and multiple mechanisms (M). Treatment persistence was compared, and the predictors of persistence were analyzed.

Results

In total, 3033 patients were enrolled in this study. Combined ASMs with different MoAs had significantly longer treatment persistence than ASMs with similar MoAs, specifically SC and M combinations. Patients receiving combined ASMs with different MoAs were less likely to discontinue treatment [adjusted hazards ratio: 0.83 (95% CI: 0.75-0.93), p < 0.001]. Among all combinations, the SC + SV2 combination had the longest treatment persistence (mean ± SD: 912.7 ± 841.6 days). Meanwhile, patients receiving the G combination had a higher risk of treatment discontinuation than those receiving the SC + SV2 combination. Underlying malignancies were associated with an increased risk of treatment discontinuation across all MoA categories. Male patients receiving the SC, SV2, and M combinations were more likely to discontinue treatment than female patients. Moreover, patients with renal disease were more likely to discontinue treatment with the SV2 combinations.

Conclusion

ASM combinations with different MoAs had superior efficacy and tolerability to ASM combinations with similar MoAs, particularly SC and M combinations. In our cohort, factors associated with treatment discontinuation included underlying malignancy, male sex, and renal disease. These findings may provide valuable insights into the use of ASM combinations if monotherapy cannot adequately control seizures.

Outpatient visit behavior in patients with epilepsy: Generalized Epilepsy is more frequently non-attendance than Focal Epilepsy

BACKGROUND

Patients with epilepsy (PWE), especially those with Idiopathic Epilepsy (GE), are at a high risk of disadvantage caused by non-adherence. It has been suggested that medical visit behavior may be a surrogate indicator of medication adherence. We hypothesized that patients with IGE would adhere poorly to visits.

METHODS

This was a retrospective study of PWE who visited the Department of Psychiatry and Neurology at Hokkaido University Hospital between January 2017 and December 2019. Demographic and clinical information on PWE were extracted from medical records and visit data from the medical information system. Non-attendance of outpatient appointments was defined as "not showing up for the day of an appointment without prior notice." Mixed-effects logistic regression analysis was conducted with non-attendance as the objective variable.

RESULTS

Of the 9151 total appointments, 413 were non-attendances, with an overall non-attendance rate of 4.5%. IGE was a more frequent non-attendance than Focal Epilepsy (FE) (odds ratio (OR) 1.94; 95% confidence interval (CI) 1.17-3.21; p = 0.010). History of public assistance receipt was associated with higher non-attendance (OR 2.04; 95% CI 1.22-3.43; p = 0.007), while higher education (OR 0.64; 95% CI 0.43-0.93; p = 0.021) and farther distance to a hospital (OR 0.33; 95% CI 0.13-0.88; p = 0.022), and higher frequency of visits (OR 0.18; 95% CI 0.04-0.86; p = 0.031) were associated with fewer non-attendances. In a subgroup analysis of patients with GE, women were associated with fewer non-attendance (OR 0.31; 95% CI 0.14-0.72; p = 0.006).

CONCLUSIONS

GE was more frequent in the non-attendance group than in the FE group. Among patients with GE, females were found to have non-attendance less frequently; however, there was no clear difference in the odds of non-attendance between Juvenile Myoclonic Epilepsy (JME) and IGE other than JME.

EEG Markers of Treatment Resistance in Idiopathic Generalized Epilepsy: From Standard EEG Findings to Advanced Signal Analysis

Idiopathic generalized epilepsy (IGE) represents a common form of epilepsy in both adult and pediatric epilepsy units. Although IGE has been long considered a relatively benign epilepsy syndrome, a remarkable proportion of patients could be refractory to treatment. While some clinical prognostic factors have been largely validated among IGE patients, the impact of routine electroencephalography (EEG) findings in predicting drug resistance is still controversial and a growing number of authors highlighted the potential importance of capturing the sleep state in this setting. In addition, the development of advanced computational techniques to analyze EEG data has opened new opportunities in the identification of reliable and reproducible biomarkers of drug resistance in IGE patients. In this manuscript, we summarize the EEG findings associated with treatment resistance in IGE by reviewing the results of studies considering standard EEGs, 24-h EEG recordings, and resting-state protocols. We discuss the role of 24-h EEG recordings in assessing seizure recurrence in light of the potential prognostic relevance of generalized fast discharges occurring during sleep. In addition, we highlight new and promising biomarkers as identified by advanced EEG analysis, including hypothesis-driven functional connectivity measures of background activity and data-driven quantitative findings revealed by machine learning approaches. Finally, we thoroughly discuss the methodological limitations observed in existing studies and briefly outline future directions to identify reliable and replicable EEG biomarkers in IGE patients.

Seizure outcome trajectories in a well-defined cohort of newly diagnosed juvenile myoclonic epilepsy patients

OBJECTIVE

To investigate the temporal course of medication response and associated prognostic factors in a cohort of juvenile myoclonic epilepsy (JME) patients over a long-term follow-up.

MATERIALS AND METHODS

Data from 113 JME patients diagnosed according to recently proposed class II criteria were retrospectively reviewed. Early sustained remission was defined as 4-year seizure remission starting within 2 years from the first antiseizure medication (ASM) intake, as opposed to delayed sustained remission. Spontaneous relapse rate (ie, not related to ASM withdrawal) was also investigated, along with factors associated with seizure relapse.

RESULTS

Four-year seizure remission was obtained by 76/113 (67.3%) subjects. Early sustained remission was achieved by 45/76 (59.2%) patients. Absence seizures were significantly associated with no-remission at multivariable multinomial logistic regression analysis. Catamenial seizures and earlier age at epilepsy onset significantly predicted delayed sustained remission. Spontaneous seizure relapse after 4-year remission occurred in 15.7% of patients with early sustained remission and in 35.5% of those with delayed sustained remission (p = 0.045). The most common concomitant factors for a spontaneous relapse were irregular lifestyle habits and pregnancy-related switch from valproate to another ASM. Patients with a history of catamenial seizures were more likely to experience a spontaneous generalized tonic-clonic seizure relapse after 4-year remission at univariable analysis.

SIGNIFICANCE

Our data support the prognostic relevance of early medication response in JME patients. Furthermore, the prognostic significance of catamenial seizures and the impact of valproate switch on seizure relapse after a prolonged remission account for the challenging therapeutic management of women with childbearing potential.

Reconsidering the role of selective sodium channel blockers in genetic generalized epilepsy

OBJECTIVE

Selective sodium channel blockers (SSCBs) have a limited use in genetic generalized epilepsy (GGE), due to their well-known risk of seizure worsening. Although their therapeutic potential in GGE has been suggested by recent evidence, electro-clinical data supporting their prescription are lacking. We aimed to investigate SSCB safety and effectiveness in a GGE cohort.

METHODS

Subjects who received SSCBs and had ≥5-year follow-up were enrolled. Lamotrigine was excluded from analysis due to its broader pharmacodynamic spectrum and its better-documented efficacy in GGE.

RESULTS

Fifty-six patients (median follow-up 28.5 years) were included. The most used SSCB was carbamazepine in 40 subjects. At the last medical observation, only 9 subjects were still receiving SSCBs. The occurrence of generalized polyspike-wave discharges (GPSWDs) predicted reduced SSCB retention in Cox multivariate analysis. A seizure reduction ≥50% occurred in 53.5% (30/56) of subjects when considering all seizure types; however, the proportion of responders increased to 67.9% when considering only generalized tonic-clonic seizures (GTCS). GPSWDs were significantly associated with a reduced response rate, whereas GGE with GTCS only syndrome with a better outcome. The switch from SSCBs to antiseizure medications licensed for GGE improved seizure control in 65% of patients. Seizure worsening was reported in 5/56 patients; juvenile myoclonic epilepsy and a family history of epilepsy were significantly associated with seizure aggravation.

CONCLUSION

SSCBs appeared effective on GTCS, but epilepsy aggravation and unsatisfactory control of other seizure types were not uncommon. Our study contributes to identifying new clinical and EEG variables associated with SSCB effectiveness and safety which may help neurologists in patients' management.

Predictors of successful valproate withdrawal in women with epilepsy

OBJECTIVE

Valproate (VPA) use was restricted due to its teratogenic risks in women with epilepsy (WWE). We aimed to assess the outcome and predictors of treatment decisions of withdrawal/switch or continuation of VPA in WWE.

METHODS

We included 214 consecutive WWE with a follow-up time of 9.57 ± 7.04 years, who have used (n = 142) or are still using VPA (n = 72) during their reproductive ages. The demographic, clinical, and electroencephalography (EEG) properties of WWE who could withdraw (successful withdrawal; n = 142) and could not withdraw VPA (unsuccessful withdrawal; n = 36) were compared statistically.

RESULTS

The main reasons for still using VPA were high risk of seizure recurrence (63.9%), cognitive impairment (27.8%), and no pregnancy prospect (8.3%). In the successful withdrawal group, 67 (47.1%) patients maintained remission after VPA withdrawal and 26 of them (38.8%) had relapse during the follow-up. The rate of side effects related to the new drugs (levetiracetam and lamotrigine) was 52/142 (36.6%). The unsuccessful withdrawal rate was 13.9% in focal epilepsy whereas it was 86.1% in generalized epilepsy (p = 0.002). Co-occurrence of three types of seizures and anti-seizure medication (ASM)-resistance was related to unsuccessful withdrawal in genetic generalized epilepsy (GGE) (p = 0.02 for both).

CONCLUSIONS

Although women with focal epilepsies are more ASM-resistant and more likely to have continuing seizures, they do not usually deteriorate after VPA discontinuation, therefore posing them to teratogenic risk is often unnecessary. In GGE, certain predictors such as previous ASM-resistance and the presence of three seizure types must be taken into account, before a withdrawal attempt of VPA treatment.

Our reasons for converting to valproic acid treatment in female patients with genetic generalized epilepsy: a retrospective, single-centre study

INTRODUCTION AND AIM

Valproic acid (Na valproate) is a broad-spectrum anti-seizure medication used in children and adolescents. It is thought to have fewer adverse effects; however, recent studies have restricted its use in women of reproductive age due to the teratogenic impacts on cognition. Although alternative drugs have been used to treat patients in clinical follow-up, some patients have to return to using valproic acid. Our study aimed to determine the rate of return to valproic acid treatment in female patients with follow-up in our centre and the reasons for the return.

MATERIALS AND METHODS

Female patients with genetic generalized epilepsy who were followed up in our centre were included in the study. Patient data were retrospectively obtained from file records. The patients were grouped by seizure subgroups, antiepileptic treatment used, electroencephalography characteristics, and seizure treatment response.

RESULTS

Sixty-three (31.7%) of the 199 patients had to return to VPA treatment. When the reasons for the discontinuation of other drugs were examined, non-response to treatment was found in 80.0% of patients, adverse medication effects in 18.3%, and 1.7% continued voluntarily. Patients who are JAE subtypes were more likely to return to VPA treatment than GTCS alone subtypes. A total of 7.4% of patients converted to VPA therapy had continued myoclonic seizures compared with 20.4% of patients treated with alternative drugs.

CONCLUSION

VPA treatment is not used as the first choice in females of reproductive age; however, some patients will only achieve seizure control with valproate, especially those with myoclonic seizures and JAE.