Mechanisms Underlying Aggressive Behavior Induced by Antiepileptic Drugs: Focus on Topiramate, Levetiracetam, and Perampanel

Differences in levetiracetam and perampanel treatment-related irritability in patients with epilepsy

PURPOSE

The present study evaluated whether patients with epilepsy who received both levetiracetam (LEV) and perampanel (PER) therapy showed side effects of irritability. The study also examined the relationship between patient characteristics and irritability when it occurred as a side effect.

METHODS

We retrospectively examined medical records of 98 patients with epilepsy who were treated with both LEV and PER at the Department of Psychiatry in the Epilepsy Center of Nishiniigata Chuo National Hospital in Japan. We performed multiple regression analyses with the presence/absence of irritability due to LEV or PER as the dependent variables and clinical characteristics of the patients as independent variables.

RESULTS

LEV and PER caused irritability in 7 and 17 of 98 patients, respectively. LEV- and PER-related irritability did not occur in the same patients. A logistic multiple regression analysis revealed that EEG findings of temporal focal epileptic discharge were significantly associated with increased incidence of irritability due to LEV. LEV-related irritability decreased significantly with higher dosages of LEV. Another logistic multiple regression analysis revealed that a psychiatric comorbidity of irritability and EEG findings of nontemporal focal epileptic discharge were significantly associated with increased incidence of irritability due to PER.

CONCLUSIONS

LEV and PER cause irritability in different patient groups. Additionally, irritability as a side effect was present only at low dosages of LEV, but PER tended to cause irritability even at high dosages.

Spermatorrhea in a Chinese patient with temporal lobe epilepsy: a case report

Epilepsy is a chronic neurological disorder that is characterized by episodes of seizure. Sexual dysfunction has been reported in patients with seizure, which mostly manifests as erectile dysfunction and premature ejaculation in men. In this study, we report the case of a 65-year-old Chinese man with frequent spermatorrhea. Electroencephalography suggested local epilepsy in the left temporal lobe. After treatment with anti-epilepsy drugs, the symptoms disappeared and did not recur. To the best of our knowledge, this is the first reported case of epilepsy-induced spermatorrhea. The symptoms of spermatorrhea are probably a rare manifestation of seizure. When repetitive stereotyped symptoms occur, seizure should be considered, and tentative anti-epileptic treatment may be a good option.

The effect of lacosamide on psychiatric comorbidities in patients with epilepsy

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Lacosamide appears to be a low-risk ASM in people with focal epilepsies.

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Lacosamide had a high retention rate in patients with psychiatric comorbidities.

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Lacosamide may provide favorable seizure outcome and improve psychiatric comorbidities in some patients similar to other ASM.

We investigated the efficacy of lacosamide (LCM) polytherapy in improving seizure outcomes and psychiatric symptoms in patients with epilepsy with psychiatric comorbidities. We retrospectively collected data from medical records of outpatients of the Department of Psychiatry of Nishiniigata Chuo Hospital Epilepsy Center in Japan. We extracted data from all patients with epilepsy and psychiatric comorbidities who had been treated with LCM. We evaluated seizure prognosis and changes in psychiatric symptoms after LCM polytherapy. After LCM administration, 19 (47.5%) patients had improvements in seizure outcomes. The other 18 (45%) patients experienced no changes in seizure outcomes, and the remaining 3 (7.5%) patients experienced worse seizure outcomes after LCM polytherapy. LCM administration improved psychiatric symptoms in 21 (52.5%) of the 40 patients; psychiatric symptoms did not change in 14 (35%) patients and worsened in 5 patients (12.5%). There was no significant association between psychiatric and seizure prognoses. LCM polytherapy may have less negative influence on psychiatric comorbidities in patients with epilepsy compared with other antiseizure medications, and may also improve seizure severity. While LCM polytherapy might improve psychiatric symptoms as seizures improve, a small number of patients experienced worsening of psychiatric symptoms despite seizure improvement.

Cognitive disorders in epilepsy II: Clinical targets, indications and selection of test instruments

This is the second of two narrative reviews on cognitive disorders in epilepsy (companion manuscript: Cognitive disorders in epilepsy I: Clinical experience, real-world evidence and recommendations). Its focus is on the clinical targets, indications, and the selection of neuropsychological test instruments. Cognitive assessment has become an essential tool for the diagnosis and outcome control in the clinical management of epilepsy. The diagnostics of basic and higher brain functions can provide valuable information on lateralized and localized brain dysfunctions associated with epilepsy, its underlying pathologies and treatment. In addition to the detection or verification of deficits, neuropsychology reveals the patient's cognitive strengths and, thus, information about the patient reserve capacities for functional restitution and compensation. Neuropsychology is an integral part of diagnostic evaluations mainly in the context of epilepsy surgery to avoid new or additional damage to preexisting neurocognitive impairments. In addition and increasingly, neuropsychology is being used as a tool for monitoring of the disease and its underlying pathologies, and it is suited for the quality and outcome control of pharmacological or other non-invasive medical intervention. This narrative review summarizes the present state of neuropsychological assessments in epilepsy, reveals diagnostic gaps, and shows the great need for education, homogenization, translation and standardization of instruments.

Behavioral alterations associated with levetiracetam in pediatric epilepsy

Levetiracetam (LEV) has an improved pharmacological profile and is one of the most commonly used antiepileptic drugs (AEDs). However, associations between this pharmacological profile and behavioral side effects have been extensively reported in pediatric populations. We assessed behavioral changes after initiation of LEV, prescribed by the treating neurologist, in Chilean patients with epilepsy aged 4-15 years. A behavioral questionnaire was applied at baseline and at two, four, and twelve weeks of treatment. Thirty patients were enrolled: 16 males, 14 females, average age 8 years (range: 4-14). By week four, 23.3% of patients showed significant behavioral alterations that persisted throughout the observation period. No significant alterations emerged after four weeks in the remaining patients. Family history of psychiatric disease and prior behavioral difficulties were predisposing factors for adverse behavioral effects. Although previous studies associated adverse behavioral effects with LEV in pediatric patients with epilepsy, we believe that this is the first study to use a prospective methodology and standardized tools to quantify the symptomatology. Adverse behavioral effects may significantly affect quality of life for patients and families, diminishing the tolerability of treatment. To ensure successful therapy and improve medical decision-making, it is essential to consider predisposing factors for drug-related adverse effects and to regularly assess for behavioral alterations during treatment.

Psychiatric Comorbidities in Pediatric Epilepsy

PURPOSE OF REVIEW

Psychiatric comorbidities are close to 5-times higher in children and youth with epilepsy (CYE) compared to general population. With epilepsy being one of the most common neurological disorders in children, we provide a timely review of psychiatric issues in CYE.

RECENT FINDINGS

A meta-analysis found a pooled prevalence of anxiety in 18.9% and depression in 13.5% of CYE. Attention deficit hyperactivity disorder (ADHD) is 2.5 to 5.5 times higher in CYE compared to healthy counterparts. Recent evidence highlights that behavioral adverse effects may lead to discontinuation of anti-epileptic drugs (AEDs) in more than 10% of CYE. Up to 70% CYE shows elevation in baseline psychological symptoms after AED initiation. Identifying psychiatric symptoms can be easily accomplished by the routine use of psychiatric screening instruments in CYE clinics, which is associated with improved health-related quality of life (HRQOL). Psychoeducation is a key component for any visit with CYE. There is some evidence of the effectiveness of behavioral psychological interventions for CYE. There are no therapeutic trials of psychotropics in CYE, but treatment recommendations based on the experience in adults with epilepsy and general population are applicable. Early diagnosis and management of psychiatric comorbidities leads to improvement in HRQOL of CYE. This requires routine screening and a multidisciplinary teamwork.

CircHivep2 contributes to microglia activation and inflammation via miR-181a-5p/SOCS2 signalling in mice with kainic acid-induced epileptic seizures

Epilepsy is a chronic brain disease characterized by recurrent seizures. Circular RNA (circRNA) is a novel family of endogenous non‐coding RNAs that have been proposed to regulate gene expression. However, there is a lack of data on the role of circRNA in epilepsy. In this study, the circRNA profiles were evaluated by microarray analysis. In total, 627 circRNAs were up‐regulated, whereas 892 were down‐regulated in the hippocampus in mice with kainic acid (KA)‐induced epileptic seizures compared with control. The expression of circHivep2 was significantly down‐regulated in hippocampus tissues of mice with KA‐induced epileptic seizures and BV‐2 microglia cells upon KA treatment. Bioinformatics analysis predicted that circHivep2 interacts with miR‐181a‐5p to regulate SOCS2 expression, which was validated using a dual‐luciferase reporter assay. Moreover, overexpression of circHivep2 significantly inhibited KA‐induced microglial activation and the expression of inflammatory factors in vitro, which was blocked by miR‐181a‐5p, whereas circHivep2 knockdown further induced microglia cell activation and the release of pro‐inflammatory proteins in BV‐2 microglia cells after KA treatment. The application of circHivep2+ exosomes derived from adipose‐derived stem cells (ADSCs) exerted significant beneficial effects on the behavioural seizure scores of mice with KA‐induced epilepsy compared to control exosomes. The circHivep2+ exosomes also inhibited microglial activation, the expression of inflammatory factors, and the miR‐181a‐5p/SOCS2 axis in vivo. Our results suggest that circHivep2 regulates microglia activation in the progression of epilepsy by interfering with miR‐181a‐5p to promote SOCS2 expression, indicating that circHivep2 may serve as a therapeutic tool to prevent the development of epilepsy.

Brivaracetam: First Canadian Experience in an Intractable Epilepsy Population

Objective:

To evaluate the effectiveness and tolerability of brivaracetam (BRV) in a refractory epilepsy population in an outpatient clinical setting.

Methods:

Retrospective medical information system review and self-report questionnaire for all patients treated with BRV until the end of 2017.

Results:

Thirty-eight patients were included, 73.7% female and mean age 36.2. The mean number of antiepileptic drugs (AEDs) for previous use was 8.9, and for current use was 2.5. Mean seizure frequency in the last 3 months was 12 per month. At 3, 6, 12, and 15 months, the 50% responder rates were 36.1%, 32%, 41.2%, and 45.5%, respectively. Patients took BRV for a median duration of 8.25 months, ranging from 7 days to 60 months. Retention rate was 75.0%, 72.0%, 59.2%, and 47.9% at 3, 6, 12, and 15 months, respectively. Overall, the main reasons for discontinuation were adverse events (AEs) (52.3%), lack of efficacy (35.3%), or both (11.8%). The rate of total AEs was 60.5% according to medical records and 85.7% according to questionnaire, including mostly tiredness, psychiatric, and memory complaints. Psychiatric side effects occurred in 31.6% according to medical records and 47.4% according to questionnaire results, which is higher than previously reported and persisted throughout the study period.

Conclusions:

BRV appears to be a useful and safe add-on treatment, even in a very refractory group of patients. In this real-life clinical setting, psychiatric AEs were found at a higher rate than previously published.

Improved irritability, mood, and quality of life following introduction of perampanel as late adjunctive treatment for epilepsy

OBJECTIVE

The objective of this study was to evaluate the efficacy and tolerability of perampanel (PER) in late adjunctive treatment of focal epilepsy. We assessed outcomes 1) according to patients' clinical profiles and the broad mechanism of action (MoA) of concomitant antiepileptic drugs (AEDs) and 2) the effects of PER on adverse events, irritability, mood, and quality of life (QOL).

METHODS

Consecutive patients commenced on PER at two epilepsy centers in Melbourne, Australia were identified. A nested cohort underwent detailed prospective assessment, while the remainder were retrospectively analyzed. Six- and 12-month efficacy endpoints were at least a 50% reduction in seizure frequency (responders) and complete seizure freedom. The prospective cohort underwent standardized validated questionnaires at 0, 1, 3, 6, and 12 months using the modified semi-structured seizure interview (SSI), Liverpool Adverse Events Profile (LAEP), Quality of Life in Epilepsy-Patient-Weighted (QOLIE-10-P), Neurological Disorders Depression Inventory Epilepsy (NDDI-E), and an Irritability Questionnaire.

RESULTS

One hundred sixty patients were followed for a median of 6 months: the mean number of prior AEDs was 6, 99% had drug-resistant epilepsy, and 72% had never experienced a prior seizure-free period of at least 6 months (=continuously refractory epilepsy). Perampanel was associated with responder and seizure freedom rates of 30.6% and 9.4% at 6 months and 19.4% and 4.4% (5.6% adjusted for the titration period) at 12 months. Having "continuously refractory epilepsy" was associated with a reduced likelihood of seizure freedom at 6 months (5% vs. 30%; p = 0.001) and 12 months (3% vs. 13%; p = 0.058). Quality of Life in Epilepsy-Patient-Weighted, irritability, and NDDI-E showed mean improvement at 6 months from baseline.

SIGNIFICANCE

Even when used as late add-on adjunctive therapy in patients with highly refractory focal epilepsy, PER can result in 12-month seizure freedom of 5.6%. The likelihood of seizure freedom was associated with prior "continuous medication refractoriness". Six months after introduction of PER patients reported improved mood, QOL, and decreased irritability.

Pyridoxine supplementation for levetiracetam-related neuropsychiatric adverse events: A systematic review

OBJECTIVE

Among people with epilepsy, levetiracetam (LEV) can cause neuropsychiatric adverse events (NPAEs) that impact negatively on quality of life. It has been suggested that pyridoxine can ameliorate LEV-related NPAEs. We conducted a systematic review of studies on the use of pyridoxine supplementation to relieve NPAEs associated with LEV therapy.

METHODS

The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, EMBASE, Scholar, Cochrane-CENTRAL (2000-2019), and EThOS platform were searched for studies on the use of pyridoxine in patients with LEV-related NPAEs. Proportions of patients reported to benefit from pyridoxine supplementation were tabulated, and a random-effect model meta-analysis was conducted.

RESULTS

Eleven retrospective studies/case reports and one randomized prospective study, mostly including pediatric populations, were identified. Retrospective studies, which were rated as low quality due to failure to control for bias, reported an overall improvement of NPAEs after pyridoxine supplementation in 72.5% (108/149) of patients. The proportion of patients showing improvement in a pooled analysis of the four largest retrospective studies (n = 134) was 72.1% (95% confidence interval (CI) 47.1-88.3), although there was high heterogeneity across studies (I² = 82%, p_{heterogeneity} < 0.01). In the only prospective trial, patients randomized to pyridoxine supplementation were more likely to show relief from NPAEs than patients not receiving supplementation (p < 0.01), but outcomes might have been affected by assessment bias.

CONCLUSION

This systematic review suggests that pyridoxine might be of benefit in relieving LEV-related NPAEs. However, the quality of the evidence is poor, and better-designed prospective studies that include quantitative as well as qualitative data are needed to define the role of pyridoxine in the management of LEV-related NPAEs.

Effectiveness and safety of perampanel as early add-on treatment in patients with epilepsy and focal seizures in the routine clinical practice: Spain prospective study (PERADON)

OBJECTIVE

Perampanel (PER) has been shown to be effective as an adjunctive therapy for controlling refractory focal-onset seizures (FOS). However, the information as early add-on for the treatment of FOS in the clinical practice is still scarce and must be further assessed.

METHODS

An observational prospective study was conducted to evaluate the effectiveness of early add-on PER, assessed as 50% responders (seizure frequency reduced by at least 50% during the last 3 months as compared with baseline) rate at 6 and 12 months, in patients with FOS in the routine clinical practice of Spain.

RESULTS

One hundred and thirteen patients (mean age: 40.3 years, 51.3% male) with FOS received PER as early add-on (1st add-on: 37.2% and 2nd: 62.8%) for a mean exposure of 11 months (mean PER dose: 6.3 mg/day at month 12). At 6 months, 50.4% and 20.4% of the patients were responders and seizure-free (respectively) relative to baseline (3 months prior to PER initiation), and at 12 months, 68.1% and 26.5% of the patients were responders and seizure-free (respectively), relative to baseline (3 months prior to PER initiation). The retention rate at 6 and 12 months was 83.2% and 80.5%, respectively. The percentage of seizure-free patients at 12 months was significantly (p = 0.033) higher when PER was added as first vs. second add-on. The number of concomitant antiepileptic drugs (AEDs) was significantly reduced from baseline to 6 and 12 months (p = 0.001). Treatment was simplified in 23.9% of patients at the end of the observation period. Drug-related adverse events (AEs), most mild or moderate, were reported in 30.1% of patients, with irritability (8%) and dizziness (7.1%) as the most frequent ones.

CONCLUSIONS

This is the first observational, prospective study to evaluate efficacy and safety of early adjunctive treatment with PER in patients with focal epilepsy at 12 months. Perampanel demonstrated a good efficacy and safety profile when used at a median dose of 6 mg/day, regardless of the combination with other AEDs. Adverse events were mild or moderate, with dizziness being the most frequent one.

Glutamate Systems in DSM-5 Anxiety Disorders: Their Role and a Review of Glutamate and GABA Psychopharmacology

Serotonin reuptake inhibitors and benzodiazepines are evidence-based pharmacological treatments for Anxiety Disorders targeting serotonin and GABAergic systems, respectively. Although clearly effective, these medications fail to improve anxiety symptoms in a significant proportion of patients. New insights into the glutamate system have directed attention toward drugs that modulate glutamate as potential alternative treatments for anxiety disorders. Here we summarize the current understanding of the potential role of glutamate neurotransmission in anxiety disorders and highlight specific glutamate receptors that are potential targets for novel anxiety disorder treatments. We also review clinical trials of medications targeting the glutamate system in DSM-5 anxiety disorders. Understanding the role of the glutamate system in the pathophysiology of anxiety disorder may aid in developing novel pharmacological agents that are effective in treating anxiety disorders.

Home-cage monitoring ascertains signatures of ictal and interictal behavior in mouse models of generalized seizures

Epilepsy is a significant contributor to worldwide disability. In epilepsy, disability can be broadly divided into two components: ictal (pertaining to the burden of unpredictable seizures and associated medical complications including death) and interictal (pertaining to more pervasive debilitating changes in cognitive and emotional behavior). In this study, we objectively and noninvasively appraise aspects of ictal and interictal behavior in mice using instrumented home-cage chambers designed to assay kinematic and appetitive behavioral measures. Through daily intraperitoneal injections of the chemoconvulsant pentylenetetrazole (PTZ) applied to C57BL/6J mice, we coordinately measure how “behavioral severity” (complex dynamic changes in movement and sheltering behavior) and convulsive severity (latency and occurrence of convulsive seizures) evolve or kindle with repeated injections. By closely studying long epochs between PTZ injections, we identify an interictal syndrome of nocturnal hypoactivity and increased sheltering behavior which remits with the cessation of seizure induction. We observe elements of this interictal behavioral syndrome in seizure-prone DBA/2J mice and in mice with a pathogenic Scn1a mutation (modeling Dravet syndrome). Through analyzing their responses to PTZ, we illustrate how convulsive severity and “behavioral” severity are distinct and independent aspects of the overall severity of a PTZ-induced seizure. Our results illustrate the utility of an ethologically centered automated approach to quantitatively appraise murine expressions of disability in mouse models of seizures and epilepsy. In doing so, this study highlights the very unique psychopharmacological profile of PTZ.

The Novel Direct Modulatory Effects of Perampanel, an Antagonist of AMPA Receptors, on Voltage-Gated Sodium and M-type Potassium Currents

Perampanel (PER) is a selective blocker of AMPA receptors showing efficacy in treating various epileptic disorders including brain tumor-related epilepsy and also potential in treating motor neuron disease. However, besides its inhibition of AMPA-induced currents, whether PER has any other direct ionic effects in different types of neurons remains largely unknown. We investigated the effects of PER and related compounds on ionic currents in different types of cells, including hippocampal mHippoE-14 neurons, motor neuron-like NSC-34 cells and U87 glioma cells. We found that PER differentially and effectively suppressed the amplitude of voltage-gated Na⁺ currents (I_Na) in mHippoE-14 cells. The IC₅₀ values required to inhibit peak and late I_Na were 4.12 and 0.78 μM, respectively. PER attenuated tefluthrin-induced increases in both amplitude and deactivating time constant of I_Na. Importantly, PER also inhibited the amplitude of M-type K⁺ currents (I_K(M)) with an IC₅₀ value of 0.92 μM. The suppression of I_K(M) was attenuated by the addition of flupirtine or ZnCl₂ but not by L-quisqualic acid or sorafenib. Meanwhile, in cell-attached configuration, PER (3 μM) decreased the activity of M-type K⁺ channels with no change in single-channel conductance but shifting the activation curve along the voltage axis in a rightward direction. Supportively, PER suppressed I_K(M) in NSC-34 cells and I_Na in U87 glioma cells. The inhibitory effects of PER on both I_Na and I_K(M), independent of its antagonistic effect on AMPA receptors, may be responsible for its wide-spectrum of effects observed in neurological clinical practice.

The impact of perampanel treatment on quality of life and psychiatric symptoms in patients with drug-resistant focal epilepsy: An observational study in Italy

An observational, prospective study has been conducted to evaluate the effects of adjunctive treatment with perampanel (PER) on psychological functioning and quality of life (QoL) in patients with drug-resistant focal epilepsy. Fifty-six adult patients treated with PER in addition to antiepileptic drugs (AEDs) were recruited in 2 Italian Epilepsy Centers. Irritability in Adult Patients with Epilepsy (I-EPI), Quality of Life in Epilepsy (QOLIE-31), Beck Depression Inventory II (BDI-II), and State-Trait Anxiety Inventory Y-1 and Y-2 (STAI) questionnaires were administered at baseline and 3 and 6 months after the treatment onset. Adverse events (AEs) were collected during the observational 6 months period. Retention rate of treatment with PER was 82.1% at 3 months and 64.3% at 6 months. Thirteen patients reported a significant seizure frequency reduction, and one seizure freedom case was observed after 4 months of PER treatment. Perampanel was stopped because of inefficacy or paradoxical effects in 28.6% of cases and because of AEs in 7.1%. The peak dose was not associated with discontinuation probability. Irritability, QoL, depression, trait, and state anxiety did not change significantly during the PER therapy. A tendency of association between higher level of irritability at baseline and PER discontinuation was found. The results of this observational study have shown that the addition of PER to AEDs may improve seizure control, does not increase levels of irritability, depression, and anxiety, and does not reduce patients' QoL. This study also confirms the importance of a comprehensive clinical assessment, including psychiatric symptoms evaluation before offering a new treatment, to improve therapy compliance.

Epileptological aspects of juvenile neuronal ceroid lipofuscinosis (CLN3 disease) through the lifespan

PURPOSE

Juvenile neuronal ceroid lipofuscinosis (CLN3 disease) is the most common neurodegenerative disorder in childhood with survival until young adult age. Visual loss is followed by epilepsy, cognitive, neuropsychiatric, and motor symptoms. We have studied the evolution of electroencephalographic (EEG) and seizure characteristics.

METHODS

Twenty-four patients were recruited via the Norwegian CLN3 disease parent association. Parents were interviewed. Medical records and EEG reports/recordings were collected. Electroencephalographic elements were classified according to Standardized computer-based organized reporting of EEG (SCORE). The evolution of EEG features along with seizure types was assessed by testing the difference in proportions with standardized normal deviate comparing findings below and above 15 years of age.

RESULTS

Mean age at study or death (n = 12) was 21.2 (10-39) years. Twenty-two patients had experienced seizures; the first was usually bilateral tonic-clonic (TC). Later, focal motor seizures frequently occurred, often with increasing multifocal and polymorphic features. Paroxysmal nonepileptic motor and autonomous symptoms were also suspected in several patients. Distinct myoclonic seizures were uncommon. In four patients, we identified episodes of bradycardia/sinus arrest. Electroencephalography showed progressive slowing of the background activity (p = 0.029). Focal epileptiform discharges were rare and mainly seen at age <10. Combined multifocal and bilateral epileptiform discharges increased in adolescence (p = 0.002).

CONCLUSION

Seizure and EEG characteristics change with time in CLN3 disease. Tonic-clonic seizures are common at onset, and multifocal motor seizures increase with age. In contrast, focal epileptiform abnormalities are more common in childhood, compared to later multifocal and bilateral discharges. This seizure disorder belongs to the combined generalized and focal epilepsies. Paucity of myoclonic seizures does not warrant classification as a classic progressive myoclonic epilepsy. When attacks with only behavior arrest occur, cardiac conduction abnormalities should be considered.