Topiramate and cognitive impairment: evidence and clinical implications

Persistent sodium currents in neurons: potential mechanisms and pharmacological blockers

Persistent sodium current (INaP) is an important activity-dependent regulator of neuronal excitability. It is involved in a variety of physiological and pathological processes, including pacemaking, prolongation of sensory potentials, neuronal injury, chronic pain and diseases such as epilepsy and amyotrophic lateral sclerosis. Despite its importance, neither the molecular basis nor the regulation of INaP are sufficiently understood. Of particular significance is a solid knowledge and widely accepted consensus about pharmacological tools for analysing the function of INaP and for developing new therapeutic strategies. However, the literature on INaP is heterogeneous, with varying definitions and methodologies used across studies. To address these issues, we provide a systematic review of the current state of knowledge on INaP, with focus on mechanisms and effects of this current in the central nervous system. We provide an overview of the specificity and efficacy of the most widely used INaP blockers: amiodarone, cannabidiol, carbamazepine, cenobamate, eslicarbazepine, ethosuximide, gabapentin, GS967, lacosamide, lamotrigine, lidocaine, NBI-921352, oxcarbazepine, phenytoine, PRAX-562, propofol, ranolazine, riluzole, rufinamide, topiramate, valproaic acid and zonisamide. We conclude that there is strong variance in the pharmacological effects of these drugs, and in the available information. At present, GS967 and riluzole can be regarded bona fide INaP blockers, while phenytoin and lacosamide are blockers that only act on the slowly inactivating component of sodium currents.

Neuroprotective potential of topiramate, pregabalin and lacosamide combination in a rat model of acute SE and intractable epilepsy: Perspectives from electroencephalographic, neurobehavioral and regional degenerative analysis

The lithium-pilocarpine model is commonly used to recapitulate characteristics of human intractable focal epilepsy. In the current study, we explored the impact of topiramate (TPM) alone and in combination with pregabalin and lacosamide administration for 6 weeks on the evolution of spontaneous recurrent seizures (SRS) and disease-modifying potential on associated neuropsychiatric comorbidities. In addition, redox impairments and neurodegeneration in hippocampus regions vulnerable to temporal lobe epilepsy (TLE) were assessed by cresyl violet staining. Results revealed that acute electrophysiological (EEG) profiling of the ASD cocktail markedly halted sharp ictogenic spikes as well as altered dynamics of brain wave oscillations thus validating the need for polytherapy vs. monotherapy. In TLE animals, pharmacological intervention for 6 weeks with topiramate 10 mg/kg in combination with PREG and LAC at the dose of 20 mg/kg exhibited marked protection from SRS incidence, improved body weight, offensive aggression, anxiety-like behavior, cognitive impairments, and depressive-like behavior (p < 0.05). Moreover, combination therapy impeded redox impairments as evidenced by decreased MDA and AchE levels and increased activity of antioxidant SOD, GSH enzymes. Furthermore, polytherapy rescued animals from SE-induced neurodegeneration with increased neuronal density in CA1, CA3c, CA3ab, hilus, and granular cell layer (GCL) of the dentate gyrus. In conclusion, early polytherapy with topiramate in combination with pregabalin and lacosamide prompted synergy and prevented epileptogenesis with associated psychological and neuropathologic alterations.

Risk of suicide and suicide-related events in subjects treated with antiseizure medications

INTRODUCTION

In the United States, it is reported that 1.4% of the general population commits suicide. It has been postulated that antiseizure medications (ASMs) can lead to the development of suicidal ideation and suicidal behavior; however, this risk is still very low and has yet to be precisely established.

AREAS COVERED

This narrative review evaluates the risk of suicide-related events (SREs) in subjects taking ASMs for various neurological disorders. Screening tools for suicidal ideation and suicidal behavior are also discussed. References for this article were found using PubMed/MEDLINE.

EXPERT OPINION

Although some ASMs can be associated with SREs, this is not yet clearly established. The mechanisms involved in suicide risk in subjects taking ASMs are multifactorial. The bidirectional relationship between depression and epilepsy, as well as other associations, should be kept in mind when interpreting any impact of ASMs in PWE. Screening for SREs, close monitoring of subjects taking ASMs are the most appropriate strategies to minimize suicide risk. More efforts should be made to achieve accurate risk stratification through prognostic models that could be applied to subjects taking ASMs. Studies exploring the association between ASMs and suicide should consider ASMs individually and control for prior SREs.

Interictal Dysphoric Disorder in Epilepsy and Its Relationship with Specific Clinical and Demographic Variables

Patients with epilepsy present a variety of psychiatric comorbidities, with mood disorders and anxiety disorders as well as interictal dysphoric disorder as the most frequent and often associated with comorbid mental conditions. Interictal dysphoric disorderand ictal and peri-ictal changes may contribute to overall clinical symptomatology in epilepsy, as well as subjective and objective adverse effects of anti-epileptic drugs. We performed a post-hoc analysis to verify the relation of interictal dysphoric disorder with specific clinical and demographic variables in people with epilepsy, including the correlation between interictal dysphoric disorder and anti-epileptic drugs. We found no correlation between the incidence of interictal dysphoric disorder and drug-resistant epilepsy, and no correlation between the incidence of interictal dysphoric disorder and sex was observed. The results of our analysis indicate that patients with interictal dysphoric disorder, compared with those with no interictal dysphoric disorder, had epilepsy onset at a later age, had had a history of psychiatric treatment and had distinctly lower, but not statistically significant, percentage of active employment status. Another finding was the frequent suicide attempts in people with epilepsy (11.5%). However, there was no relationship with interictal dysphoric disorder. We also did not find any evidence supporting the impact of epileptic medication on the incidence of interictal dysphoric disorder nor did the data contribute to support the evidence of interictal dysphoric disorder as a standing-alone phenomenon. An essential issue in epilepsy is awareness and understanding of interictal dysphoric disorder and concomitant mental health abnormalities as this is crucial for clinical practice and may significantly determine the progression and management of epilepsy if it remains ignored, and hence lead to a severe decline in life quality.

Efficacy of topiramate in reducing second-generation antipsychotic-associated weight gain among children: A systematic review and meta-analysis

AIMS

To conduct a systematic review and meta-analysis with the aim of synthesizing existing data on the efficacy and safety of topiramate as an adjunctive treatment for reducing second-generation antipsychotic (SGA)-associated weight gain in children aged 4-18 years.

METHODS

We conducted a comprehensive search of PubMed, Embase, PsychNet and Web of Science from time of their inception up to 12 February 2024, including randomized controlled trials that compared SGA treatment with and without topiramate co-administration in children. The primary outcomes were changes in body weight and body mass index (BMI). Heterogeneity was assessed using I2 statistics.

RESULTS

This systematic review included five randomized trials, totalling 139 participants (43.9% female; mean [SD] age 11.9 [3.5] years). Four of these trials were included in the meta-analysis, comprising 116 subjects. We found that topiramate was significantly effective both in reducing SGA-associated weight gain, with a mean difference of -2.80 kg (95% confidence interval [CI] -5.28 to -0.31; p = 0.037, I2 = 86.7%) and a standardized mean difference (SMD) of -1.33 (95% CI -2.14 to -0.51; p = 0.014, I2 = 31.7%), and in reducing BMI change compared to placebo (SMD -1.90, 95% CI -3.09 to -0.70; p = 0.02, I2 = 0%). Sedation risk was lower with topiramate than with placebo (odds ratio 0.19, 95% CI 0.11-0.32; p < 0.01, I2 = 0%). No significant differences were found in dropouts, any other side effects, and metabolic parameters, such as triglycerides, total cholesterol, low-density lipoprotein, high-density lipoprotein, and glucose. None of the included studies reported assessments on cognitive side effects.

CONCLUSION

This meta-analysis suggests that topiramate is an effective and safe option for mitigating SGA-associated weight gain in children.

Interictal Dysfunctions of Attention, Vigilance, and Executive Functions in Migraine and Their Reversal by Preventive Treatment: A longitudinal Controlled Study

OBJECTIVE

To assess attention, vigilance, and executive functions in migraine patients during headache-free (interictal) periods and in healthy controls without migraine and to study the impact of migraine preventive treatment on these cognitive functions.

METHODS

Preventive drug-naive migraine patients, aged ≥18 years, without a history of medication overuse were studied and compared to non-migraine controls. Psychiatric comorbidity was screened by Patient Health Questionnaire-9, and those who screened positive were evaluated further by specific scales. The Epworth Sleepiness Scale assessed subjective complaints of sleep quality. Cognitive functions were assessed by Mini-Mental State Examination (MMSE), digit span forward and backward (DS-F, DS-B), trail-making tests (TMT-A and B) and Stroop word (SW), Stroop color (SC), and Stroop interference (SI) tests. Cognitive test scores at the end of 6 months following treatment were compared to baseline scores.

RESULTS

One hundred and fifty migraine patients and controls each were studied. Compared to controls, migraine patients performed significantly worse in DS-B ( P < 0.0001), TMT-A ( P = 0.00004), TMT-B ( P < 0.0001), SW ( P < 0.0001), SC ( P < 0.0001), and SI ( P = 0.0221). MMSE scores did not differ between patients and the controls ( P = 0.3224). Compared to the patients without psychiatric comorbidity, migraine patients with psychiatric comorbidity showed no significant differences in the cognitive test scores. Significant improvement in all cognitive test scores ( P < 0.001) was observed after 6 months of treatment.

CONCLUSION

Migraine patients, compared to non-migraine controls, showed deficits in attention, vigilance, and executive functions during the interictal period, which improved with successful preventive treatment. Psychiatric comorbidities did not have a significant impact on cognitive dysfunctions.

Differences in health-related quality of life and somatic symptoms in employed and unemployed patients with epilepsy

This study compared overall and specific aspects of health-related quality of life (HRQOL) and self-report of somatic, anxiety, and depressive symptoms between employed (n = 71) and unemployed (n = 48) patients with epilepsy (PWE). The Quality of Life in Epilepsy (QOLIE-89) and the Personality Assessment Inventory (PAI) were examined. The unemployed group reported significantly worse overall HRQOL including aspects of HRQOL related to epilepsy, physical health, mental health, and cognitive function. Among these four, physical health related HRQOL revealed the most difference between groups. While there were no differences between the groups in the level of social support and social isolation, the unemployed group reported worse social function with respect to work and driving. The unemployed group reported significantly greater somatic symptoms, but not anxiety and depressive symptoms. When specifically examining the subscales of the Somatic Concerns scale, conversion and health concerns, but not somatization, were greater in the unemployed group. Among the Depression subscales, the unemployed group reported greater physiologically manifested depressive symptoms. These findings suggest that along with optimizing seizure control, identifying and addressing presence of physical limitations, dysfunction, and somatic symptoms are also of importance in the care of PWE, particularly for those who are unemployed.

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.

Ameliorative Effect of Cannabidiol on Topiramate-Induced Memory Loss: The Role of Hippocampal and Prefrontal Cortical NMDA Receptors and CREB/BDNF Signaling Pathways in Rats

Cannabidiol (CBD) is a promising neurological agent with potential beneficial effects on memory and cognitive function. The combination of CBD and topiramate in the treatment of some neurological diseases has been of great interest. Since Topiramate-induced memory loss is a major drawback of its clinical application and the overall effect of the combination of CBD and topiramate on memory is still unclear, here we investigated the effect of CBD on topiramate-induced memory loss and the underlying molecular mechanisms. A one trial step-through inhibitory test was used to evaluate memory consolidation in rats. Moreover, the role of N-methyl-D-aspartate receptors (NMDARs) in the combination of CBD and topiramate in memory consolidation was evaluated through the intra-CA1 administration of MK-801 and NMDA. Western blot analysis was used to evaluate variations in brain-derived neurotrophic factor (BDNF) and phosphorylated cyclic AMP response element-binding protein (pCREB)/CREB ratio in the prefrontal cortex (PFC) and hippocampus (HPC). While the intraperitoneal (i.p.) administration of topiramate (50, 75, and 100 mg/kg) significantly reduced inhibitory time latency, the i.p. administration of CBD (20 and 40 mg/kg) could effectively reverse these effects. Similarly, the sub-effective doses of NMDA plus CBD (10 mg/kg) could improve the topiramate-induced memory loss along with an enhancement in BDNF and pCREB expression in the PFC and HPC. Contrarily, the administration of sub-effective doses of the NMDAR antagonist (MK-801) diminished the protective effects of CBD (20 mg/kg) on topiramate-induced memory loss associated with decreased BDNF and pCREB levels in the PFC and HPC. These findings suggest that CBD can improve topiramate-induced memory impairment, partially by the NMDARs of the PFC and HPC, possibly regulated by the CREB/BDNF signaling pathway.

Research Status, Synthesis and Clinical Application of Antiepileptic Drugs

According to the 2017 ILAE's official definition, epilepsy is a slow brain disease state characterized by recurrent episodes. Due to information released by ILAE in 2017, it can be divided into four types, including focal epilepsy, generalized epilepsy, combined generalized, and focal epilepsy, and unknown epilepsy. Since 1989, 24 new antiepileptic drugs have been approved to treat different types of epilepsy. Besides, there are a variety of antiepileptic medications under clinical monitoring. These novel antiepileptic drugs have plenty of advantages. Over the past 33 years, there have been many antiepileptic drugs on the mearket, but no one has been found that can completely cure epilepsy. In this paper, the mentioned drugs were classified according to their targets, and the essential information, and clinical studies of each drug were described. The structure-activity relationship of different chemical structures was summarized. This paper provides help for the follow-up research on epilepsy drugs.

Cognitive effect of antiseizure medications in medial temporal lobe epilepsy

BACKGROUND AND PURPOSE

The specific effects of antiseizure medications (ASMs) on cognition are a rich field of study, with many ongoing questions. The aim of this study was to evaluate these effects in a homogeneous group of patients with epilepsy to guide clinicians to choose the most appropriate medications.

METHODS

We retrospectively identified 287 refractory patients with medial temporal lobe epilepsy associated with hippocampal sclerosis. Scores measuring general cognition (global, verbal and performance IQ), working memory, episodic memory, executive functions, and language abilities were correlated with ASM type, number, dosage and generation (old vs. new). We also assessed non-modifiable factors affecting cognition, such as demographics and epilepsy-related factors.

RESULTS

Key parameters were total number of ASMs and specific medications, especially topiramate (TPM) and sodium valproate (VPA). Four cognitive profiles of the ASMs were identified: (i) drugs with an overall detrimental effect on cognition (TPM, VPA); (ii) drugs with negative effects on specific areas: verbal memory and language skills (carbamazepine), and language functions (zonisamide); (iii) drugs affecting a single function in a specific and limited area: visual denomination (oxcarbazepine, lacosamide); and (iv) drugs without documented cognitive side effects. Non-modifiable factors such as age at testing, age at seizure onset, and history of febrile seizures also influenced cognition and were notably influenced by total number of ASMs.

CONCLUSION

We conclude that ASMs significantly impact cognition. Key parameters were total number of ASMs and specific medications, especially TPM and VPA. These results should lead to a reduction in the number of drugs received and the avoidance of medications with unfavorable cognitive profiles.

Long-term effect associated with seizures and dynamic effect associated with treatment on cognitive dysfunction of adult patients with focal epilepsy as evaluated by the Trail Making Test

OBJECTIVE

This study was performed to clarify the utility of the Trail Making Test (TMT) in evaluating the effects of the course of epilepsy on cognitive function by evaluating the course of epileptic seizures and the results of the TMT over time.

METHODS

We performed the TMT twice at a 1-year interval for each patient with focal epilepsy. We performed multiple regression analyses with the first TMT scores as dependent variables and clinical features as independent variables. Next, we performed a multivariate analysis of covariance (MANCOVA) to evaluate the difference between the first and second TMT scores for patients in each seizure prognosis group.

RESULTS

We enrolled 132 adult patients in this study. Multiple regression analyses showed that longer active seizure periods were associated with worse first TMT-B performance (β = .318, p < .001) and B-A (β = .377, p < .001) and that the number of antiseizure medicines was associated with worse first TMT-A performance (β = .186, p = .025). In addition, topiramate and zonisamide adversely affected TMT performance. MANCOVA showed an interaction between the prognosis of TMT-B performance and the seizure prognosis [F(2, 120) = 3.68, p = .028]. Subeffect tests revealed that the second TMT-B performance improved only in the seizure improvement group [F(1, 10) = 10.07, p = .01].

SIGNIFICANCE

Epileptic seizures were shown to be associated with both long-term and dynamic adverse effects on cognitive function evaluated with the TMT in adult patients with focal epilepsy. Seizure control is important for improving the cognitive function of patients with epilepsy; however, the potential adverse effects of polypharmacy and some antiseizure medicines such as zonisamide and topiramate on cognitive function should be considered.

Modulation of GABAB receptors in the insula bidirectionally affects associative memory of epilectic rats in both spatial and non-spatial operant tasks

Background

Stimulation of gamma-aminobutyric acid (GABA) activity through GABA receptor agonists is the basic mechanism of many anticonvulsant drugs. Nevertheless, many of these GABergic drugs have adverse cognitive effects. We previously found that GABAB receptors (GABA_BRs) in the insula regulate operant associative memory in healthy rats. The present study aimed at investigating the effects of GABA_BR modulation in the insula on operant associative memory in epileptic rats, along with the underlying mechanisms.

Methods

The lithium-pilocarpine model of temporal lobe epilepsy (TLE) was established in male Sprague-Dawley rats. A 22-gauge stainless-steel guide cannula was surgically implanted into the granular insula cortex of the epileptic rats. Baclofen (125 ng/μl, 1 μl), CGP35348 (12.5 μg/μl, 1 μl), or saline (1 μl) was slowly infused through the guide cannula. The Intellicage automated behavioral testing system was used to evaluate operant associative memory of the epileptic rats, including non-spatial operant tasks (basic nosepoke learning and skilled nosepoke learning) and spatial operant tasks (chamber position learning). The expression of the GABA_BR subunits GB1 and GB2 in the insula was examined by immunofluorescence and Western blotting.

Results

The Intellicage tests demonstrated that baclofen significantly impaired basic nosepoke learning, skilled nosepoke learning and chamber position learning of the epileptic rats, while CGP35348 boosted these functions. Immunofluorescence staining revealed that GB1 and GB2 were expressed in the insula of the epileptic rats, and Western blotting analysis showed that baclofen enhanced while CGP35348 inhibited the expression of these subunits.

Conclusion

GABA_BRs in the insula bidirectionally regulate both spatial and non-spatial operant associative memory of epileptic rats. Effects of GABA_BRs on cognition should be taken into account when evaluating new possible treatments for people with epilepsy.

Migraine Pharmacological Treatment and Cognitive Impairment: Risks and Benefits

Migraine is a common neurological disorder impairing the quality of life of patients. The condition requires, as an acute or prophylactic line of intervention, the frequent use of drugs acting on the central nervous system (CNS). The long-term impact of these medications on cognition and neurodegeneration has never been consistently assessed. The paper reviews pharmacological migraine treatments and discusses their biological and clinical effects on the CNS. The different anti-migraine drugs show distinct profiles concerning neurodegeneration and the risk of cognitive deficits. These features should be carefully evaluated when prescribing a pharmacological treatment as many migraineurs are of scholar or working age and their performances may be affected by drug misuse. Thus, a reconsideration of therapy guidelines is warranted. Furthermore, since conflicting results have emerged in the relationship between migraine and dementia, future studies must consider present and past pharmacological regimens as potential confounding factors.

Topiramate-Induced Suicidal Ideation and Olfactory Hallucinations: A Case Report

Antiepileptic drugs prescribed in the context of migraine have been reported to be potentially linked with an increased risk of suicidal ideation and behavior. Meta-analyses support the evidence that amongst antiepileptic drugs, Topiramate has the greatest potential for facilitating the occurrence of suicidal ideation and behavior. Studies indicate that this occurs via the increased incidence of mood disorders amongst the population with migraines using Topiramate as a treatment, with a slow and progressive onset of suicidal ideation (if any). We discuss the unique case of a 43-year-old man known to have chronic migraines, who presented with intense rapid-onset suicidal ideation and olfactory hallucinations, three weeks after the introduction of Topiramate for chronic migraines. After a negative extensive investigation panel to rule out common organic diseases, Topiramate was ceased. The suicidal ideation and olfactory hallucinations resolved in less than 24 h without further interventions. This case report highlights that rapid-onset suicidal ideation and olfactory hallucinations could be linked as an unusual side effect to the introduction of Topiramate. The removal of Topiramate from the patient’s pharmacological treatments prevented further psychological distress linked to ego-dystonic suicidal ideation and a resolution of olfactory hallucinations. He was discharged 48 h later.

High prevalence of psychiatric comorbidities in children and adolescents at a tertiary epilepsy center

BACKGROUND

Epilepsy is highly comorbid with psychiatric disorders and a significant amount of the morbidity related to epilepsy is in fact a result of psychiatric comorbidities.

OBJECTIVE

To investigate the frequency of different psychiatric comorbidities in children with refractory epilepsy.

METHODS

We present preliminary observational data from a series of patients (n=82) examined in the psychiatric branch of a tertiary epilepsy center in Rio de Janeiro, Brazil. Patients were classified as presenting autism spectrum disorders, mood disorders, anxiety disorders, disruptive disorders, attention deficit hyperactivity disorder (ADHD), intellectual development disorder, psychotic episode, dissociative/conversive disorders or others. We determined the frequency of each disorder, along with demographic data, medications prescribed, electroencephalogram findings and additional medical examinations and consultations.

RESULTS

The most common comorbidities in our sample were autism spectrum disorders and ADHD. Antipsychotics and selective serotonin uptake inhibitors were the most commonly prescribed psychiatric medications.

CONCLUSIONS

Knowledge about the prevalence of such comorbidities may provide more targeted interventions in Psychiatry and Psychology services linked to epilepsy centers.

Identifying nootropic drug targets via large-scale cognitive GWAS and transcriptomics

Broad-based cognitive deficits are an enduring and disabling symptom for many patients with severe mental illness, and these impairments are inadequately addressed by current medications. While novel drug targets for schizophrenia and depression have emerged from recent large-scale genome-wide association studies (GWAS) of these psychiatric disorders, GWAS of general cognitive ability can suggest potential targets for nootropic drug repurposing. Here, we (1) meta-analyze results from two recent cognitive GWAS to further enhance power for locus discovery; (2) employ several complementary transcriptomic methods to identify genes in these loci that are credibly associated with cognition; and (3) further annotate the resulting genes using multiple chemoinformatic databases to identify "druggable" targets. Using our meta-analytic data set (N = 373,617), we identified 241 independent cognition-associated loci (29 novel), and 76 genes were identified by 2 or more methods of gene identification. Actin and chromatin binding gene sets were identified as novel pathways that could be targeted via drug repurposing. Leveraging our transcriptomic and chemoinformatic databases, we identified 16 putative genes targeted by existing drugs potentially available for cognitive repurposing.

Invasive Electrophysiology for Circuit Discovery and Study of Comorbid Psychiatric Disorders in Patients With Epilepsy: Challenges, Opportunities, and Novel Technologies

Intracranial electroencephalographic (iEEG) recordings from patients with epilepsy provide distinct opportunities and novel data for the study of co-occurring psychiatric disorders. Comorbid psychiatric disorders are very common in drug-resistant epilepsy and their added complexity warrants careful consideration. In this review, we first discuss psychiatric comorbidities and symptoms in patients with epilepsy. We describe how epilepsy can potentially impact patient presentation and how these factors can be addressed in the experimental designs of studies focused on the electrophysiologic correlates of mood. Second, we review emerging technologies to integrate long-term iEEG recording with dense behavioral tracking in naturalistic environments. Third, we explore questions on how best to address the intersection between epilepsy and psychiatric comorbidities. Advances in ambulatory iEEG and long-term behavioral monitoring technologies will be instrumental in studying the intersection of seizures, epilepsy, psychiatric comorbidities, and their underlying circuitry.

Protective effects of forced exercise against topiramate-induced cognition impairment and enhancement of its antiepileptic activity: molecular and behavioral evidences

Propose/aim of study: Forced exercise can act as a neuroprotective factor and cognitive enhancer. The aim of the current study was to evaluate the effects of forced exercise on topiramate (TPM) induced cognitive impairment and also on TPM anti-seizure activity and neurodegeneration status after seizure.Material and method: Forty adult male rats were divided into four groups receiving normal saline, TPM (100 mg/kg), TPM in combination with forced exercise and forced exercise only respectively for 21 days. MWM test, and PTZ induced seizure were used and some oxidative, inflammatory and apoptotic biomarkers were measured for assessment of experimental animals.Results: Forced exercise in combination with TPM could abolish the TPM induced cognitive impairment and potentiates its anti-seizure activity. Also forced exercise in combination with TPM decreased malondialdehyde (MDA), tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) and Bax protein, while caused increase in superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) activities after PTZ administration.Conclusion: It seems that forced exercise could act as an adjunct therapy with TPM for management of induced cognitive impairment and can also potentiate TPM antiepileptic and neuroprotective effects.

Executive functioning in psychiatric patients with deliberate self-harm, as compared with a psychiatric and a healthy comparison group

Introduction: Deliberate self-harm (DSH) is a common symptom in psychiatric disorders. It is a cross-diagnostic symptom, although it has mainly been associated with borderline personality disorder (BPD). Research has suggested an association between DSH and deficits in executive functioning. The main aim of the current study was to assess three specific aspects of executive functioning (EF) (working memory, inhibition and cognitive flexibility) among psychiatric patients with DSH, compared to a clinical and a healthy comparison group.Methods: Thirty psychiatric patients with DSH, 29 psychiatric patients without DSH and 29 healthy individuals were assessed with regard to psychiatric illness, self-harming behavior, EF, general cognitive functioning level and measures of psychopathology. The results were analyzed by means of ANOVA, regression analysis, Chi-square, and correlation analysis.Results: The patients with DSH showed deficits in cognitive flexibility and inhibition as compared to healthy individuals. In addition, the patients with DSH had greater deficits in cognitive flexibility than the patients without DSH; this effect was independent of concurrent severity of depressive symptoms but not independent of borderline symptomatology.Conclusion: Psychiatric patients with DSH may have deficits in cognitive flexibility as compared to both the healthy and clinical comparison groups. The results partly differ from previous related studies in the field. It is unclear to which extent the deficits in cognitive flexibility are due to other factors. More research is needed to understand the implications of such deficits, and if the results could be used for adapting treatment services and strategies. Future studies should include more similar comparison groups.

Examination of the Flynn effect in German patients with epilepsy assessed with the Wechsler Adult Intelligence Scale (WAIS) III and IV

The Flynn effect describes an increase in intelligence quotient (IQ) in the general population of about 3 points per decade. While this effect is well established in healthy individuals, research exploring the link to brain pathologies is scarce. We investigated the Flynn effect in a German sample of 203 patients with epilepsy with left, right, and bilateral lesions. Intelligence quotient values were obtained using the Wechsler Adult Intelligence Scales (WAIS) III and IV. Our results showed a stable Flynn effect with nearly no difference in adjusted full scale IQ (FSIQ) scores (0.02 IQ points) between the WAIS-III and WAIS-IV samples. There were no significant interactions between the side of pathology and corrected IQ values. Our sample showed a tendency towards performing worse in the WAIS-IV in three out of four subscales independently of the Flynn effect, pointing out methodological differences between the newer Wechsler editions. However, although patients with bilateral lesions performed worst across all subscales, they exhibited a similar pattern as patients with lesions in the left or right hemisphere, indicating that also more severe forms of brain pathologies can profit from the mechanisms behind the Flynn effect.

Exploring the genetic overlap between psychiatric illness and epilepsy: A review

There is a long-documented epidemiological link between epilepsy and psychiatric disorders. People with epilepsy are at an increased risk for a variety of psychiatric illnesses, as are their family members, and people with epilepsy may experience psychiatric side effects because of their antiepileptic drugs (AEDs). In recent years, large-scale, collaborative international studies have begun to shed light on the role of genetic variation in both epilepsy and psychiatric illnesses, such as schizophrenia, depression, and anxiety. But so far, finding shared genetic links between epilepsy and psychiatric illness has proven surprisingly difficult. This review will discuss the prevalence of psychiatric comorbidities in epilepsy, recent advances in genetic research into both epilepsy and psychiatric illness, and the extent of our current knowledge of the genetic overlap between these two important neurobiological conditions.

Pharmaco-fMRI: A Tool to Predict the Response to Antiepileptic Drugs in Epilepsy

Pharmacological treatment with antiepileptic medications (AEDs) in epilepsy is associated with a variety of neurocognitive side effects. However, the mechanisms underlying these side effects, and why certain brain anatomies are more affected still remain poorly understood. Advanced functional magnetic resonance imaging (fMRI) methods, such as pharmaco-fMRI, can investigate medication-related effects on brain activities using task and resting state fMRI and showing reproducible activation and deactivation patterns. This methodological approach has been used successfully to complement neuropsychological studies of AEDs. Here we review pharmaco-fMRI studies in people with epilepsy targeting the most-widely prescribed AEDs. Pharmco-fMRI has advanced our understanding of the impact of AEDs on specific brain networks and thus may provide potential biomarkers to move beyond the current “trial and error” approach when commencing anti-epileptic medication.

Ten things every neurologist needs to know about neuropsychological assessments and interventions in people with epilepsy

This paper describes 10 core features of a neuropsychological assessment with the aim of helping neurologists understand the unique contribution the evaluation can make within the wider context of diagnostic methods in epilepsy. The possibilities, limitations and cautions associated with the investigation are discussed under the following headings. (1) A neuropsychological assessment is a collaborative investigation. (2) Assessment prior to treatment allows for the accurate assessment of treatment effects. (3) The nature of an underlying lesion and its neurodevelopmental context play an important role in shaping the associated neuropsychological deficit. (4) Cognitive and behavioural impairments result from the essential comorbidities of epilepsy which can be considered as much a disorder of cognition and behaviour as of seizures. (5) Patients' subjective complaints can help us understand objective cognitive impairments and their underlying neuroanatomy, resulting in improved patient care. At other times, patient complaints reflect other factors and require careful interpretation. (6) The results from a neuropsychological assessment can be used to maximize the educational and occupational potentials of people with epilepsy. (7) Not all patients are able to engage with a neuropsychological assessment. (8) There are limitations in assessments conducted in a second language with tests that have been standardized on different populations from that of the patient. (9) Adequate intervals between assessments maximize sensitivity to meaningful change. (10) Patients should be fully informed about the purpose of the assessment and have realistic expectations of the outcome prior to referral.

Seizure in Alzheimer's Disease: An Underestimated Phenomenon

Alzheimer's disease (AD) is considered as a potential risk factor for the development of seizure due to neurodegeneration and imbalance between stimulatory and inhibitory circuits in the brain. Seizure could occur in any point during the course of AD, and its presentation varies from fluctuation in cognitive domains to more typical seizures. The clinical diagnosis of seizure in patients with dementia may be challenging due to difficulty in history taking and clinical assessment. No paraclinic methods other than electroencephalogram (EEG) could provide arguments for the diagnosis of AD-related seizures (neither imaging modalities nor cerebrospinal fluid biomarkers). Standard 30-minute EEG may not be sufficiently sensitive to detect epileptiform discharges. In the present study, we aim to review different aspects of seizure in AD, including seizure prevalence, risk factors, underlying mechanisms, electroencephalographic findings, clinical presentations, impact of seizures on AD, and treatment options.

Topiramate mitigates weight gain in antipsychotic-treated patients with schizophrenia: meta-analysis of randomised controlled trials

OBJECTIVE

Weight gain is one of the most challenging issues in patients with schizophrenia treated with antipsychotics. Several meta-analyses have been conducted to review the efficacy of topiramate in reducing weight, however, several issues regarding the methodology had arisen of which make the results remain ambiguous.

METHODS

We conducted a meta-analysis of randomised controlled trials about the use of topiramate in patients with schizophrenia for weight reduction. Ten double-blinded randomised placebo-controlled trials and seven open-label randomised controlled trials included 905 patients.

RESULTS

Patients treated with topiramate experienced a greater reduction in body weight and BMI. Patients in countries of the lower overweight population showed more significant BMI reduction. Besides, studies from the Middle East and South Asia showed the greatest effect in body weight change, followed by East Asia, then Europe/America. Topiramate group was outperformed control group with significant psychopathology improvement. No difference between two groups regarding the overall side effects.

CONCLUSIONS

Topiramate was significantly superior to control group in mitigating weight gain and psychopathology in antipsychotic-treated patients with schizophrenia. The effects of topiramate augmentation need further investigations in larger definitive studies using methodological rigor and thorough assessments.

Developments in depression in epilepsy: screening, diagnosis, and treatment

INTRODUCTION

Depression is one of the most frequent comorbidities in epilepsy affecting between 17% and 22% of patients, but it is still underdiagnosed and undertreated. Areas covered: This paper discusses recent advances about screening, diagnosis, and treatment of depression in epilepsy taking into account the heterogeneity of clinical scenarios where depression can occur. Expert opinion: A number of screening instruments are now validated for adults with epilepsy, and their psychometric properties are discussed but the NDDI-E is the most practical and cost-effective. Challenges in diagnosing depression in epilepsy are discussed including reasons for the atypical features of mood disorders in epilepsy. Psychological treatments and/or SSRIs are indicated, but the level of evidence is still low. Even if there is no reason to hypothesise that internationally accepted guidelines of treatment of depression outside epilepsy may not be valid, rigorous studies are needed in order to have proper outcome measures. Epilepsy centers should have well-defined care pathways for depression in order to provide access to mental health support when needed.

A multidisciplinary approach to the clinical management of Prader-Willi syndrome

Background

Prader–Willi syndrome (PWS) is a complex neuroendocrine disorder affecting approximately 1/15,000–1/30,000 people. Unmet medical needs of individuals with PWS make it a rare disease that models the importance of multidisciplinary approaches to care with collaboration between academic centers, medical homes, industry, and parent organizations. Multidisciplinary clinics support comprehensive, patient‐centered care for individuals with complex genetic disorders and their families. Value comes from improved communication and focuses on quality family‐centered care.

Methods

Interviews with medical professionals, scientists, managed care experts, parents, and individuals with PWS were conducted from July 1 to December 1, 2016. Review of the literature was used to provide support.

Results

Data are presented based on consensus from these interviews by specialty focusing on unique aspects of care, research, and management. We have also defined the Center of Excellence beyond the multidisciplinary clinic.

Conclusion

Establishment of clinics motivates collaboration to provide evidence‐based new standards of care, increases the knowledge base including through randomized controlled trials, and offers an additional resource for the community. They have a role in global telemedicine, including to rural areas with few resources, and create opportunities for clinical work to inform basic and translational research. As a care team, we are currently charged with understanding the molecular basis of PWS beyond the known genetic cause; developing appropriate clinical outcome measures and biomarkers; bringing new therapies to change the natural history of disease; improving daily patient struggles, access to care, and caregiver burden; and decreasing healthcare load. Based on experience to date with a PWS multidisciplinary clinic, we propose a design for this approach and emphasize the development of “Centers of Excellence.” We highlight the dearth of evidence for management approaches creating huge gaps in care practices as a means to illustrate the importance of the collaborative environment and translational approaches.

Diagnosing and managing migraine in children and young people

This article gives an overview of migraine in children. It outlines the epidemiology of the condition and describes presentation with headache and other symptoms and linked conditions. It aims to raise awareness of the diagnosis of migraine and its impact on children and young people, their families and school life. The author also describes methods of diagnosis and management, and the importance of recognising and of avoiding medication overuse.

Topiramate protects apoE-deficient mice from kidney damage without affecting plasma lipids

Topiramate is an anticonvulsant drug also prescribed for migraine prophylaxis that acts through several mechanisms of action. Several studies indicate that topiramate induces weight loss and a moderate reduction of plasma lipids and glucose. Based on these favourable metabolic effects, aim of this study was to evaluate if topiramate could modulate atherosclerosis development and protect target organs of dysmetabolic conditions. Thirty apoE-deficient mice were divided into three groups and fed for 12 weeks a high fat diet (Control) or the same diet containing topiramate at 0.125% and 0.250%. Body weight, water and food intake were monitored throughout the study. Plasma lipids and glucose levels were measured and a glucose tolerance test was performed. Atherosclerosis development was evaluated in the whole aorta and at the aortic sinus. Histological analysis of liver, kidney and adipose tissue was performed. Topiramate did not affect weight gain and food intake. Glucose tolerance and plasma lipids were not changed and, in turn, atherosclerosis development was not different among groups. Topiramate did not modify liver and adipose tissue histology. Conversely, in the kidneys, the treatment reduced the occurrence of glomerular lipidosis by decreasing foam cells accumulation and reducing the expression of inflammatory markers. Blood urea nitrogen levels were also reduced by treatment. Our results indicate that topiramate does not affect atherosclerosis development, but preserves kidney structure and function. The study suggests that topiramate could be investigated in drug repurposing studies for the treatment of glomerular lipidosis.

Cognitive and fatigue side effects of anti-epileptic drugs: an analysis of phase III add-on trials

We aimed to investigate the terms used to refer to cognitive and fatigue related side effects and their prevalence in phase III add-on clinical trials of anti-epileptic drugs (AEDs). We extracted data from publicly available FDA documents as well as the published literature. Target drug doses were then calculated as drug loads and divided into three categories (low, average, high). The odds ratio of developing the side effects was calculated for each drug load, and the presence of a dose-response effect was also assessed. We found that the cognitive terms used across trials were very variable, and data on discontinuation rates were limited. Placebo rates for cognitive side effects ranged from 0 to 10.6% while those for fatigue ranged from 2.5 to 37.7%. Keeping in mind the variable placebo rates and terminology, the majority of AEDs exhibited a clear dose response effect and significant odds ratios at high doses except brivaracetam and zonisamide for the cognitive side effects and tiagabine, topiramate, and zonisamide for the fatigue side effects. Due to their clinical relevance and impact on quality of life, new trials should make data related to the prevalence and discontinuation rates of these side effects publicly available. Given the clear dose response effect, physicians should consider aiming for lower drug loads and adjusting doses to improve tolerability.

Epilepsy and Psychiatric Comorbidities: Drug Selection

Purpose of review The pharmacological treatment of patients with epilepsy and psychiatric comorbidities may sometimes represent a therapeutic challenge. This review is focused on the pharmacological management of patients with epilepsy and psychiatric problems in terms of rationalization of the antiepileptic drug (AED) treatment and the pharmacological management of the most clinically relevant psychiatric comorbidities, namely mood and anxiety disorders, psychoses, and attention deficit hyperactivity disorder (ADHD). Recent findings Up to 8% of patients with drug-resistant epilepsy develop treatment-emergent psychiatric adverse events of AED regardless of the mechanism of action of the drug and this is usually related to an underlying predisposition given by the previous psychiatric history and the involvement of mesolimbic structures. Careful history taking, periodic screening for mood and anxiety disorders, low starting doses, and slow titration schedules can reduce the possibility of AED-related problems. A pragmatic checklist for the pharmacological management of patients with epilepsy and psychiatric disorders is presented. Summary patients should be informed of potential behavioral effects of AEDs but no drugs should be excluded a priori. Any psychiatric comorbidity should be addressed in the appropriate setting and full remission and recovery should always represent the first goal of any therapeutic intervention. Neurologists should be aware of the side effects of major psychotropic drug classes in order to fully counsel their patients and other health professionals involved.

Chronic antiepileptic drug use and functional network efficiency: A functional magnetic resonance imaging study

AIM

To increase our insight in the neuronal mechanisms underlying cognitive side-effects of antiepileptic drug (AED) treatment.

METHODS

The relation between functional magnetic resonance-acquired brain network measures, AED use, and cognitive function was investigated. Three groups of patients with epilepsy with a different risk profile for developing cognitive side effects were included: A “low risk” category (lamotrigine or levetiracetam, n = 16), an “intermediate risk” category (carbamazepine, oxcarbazepine, phenytoin, or valproate, n = 34) and a “high risk” category (topiramate, n = 5). Brain connectivity was assessed using resting state functional magnetic resonance imaging and graph theoretical network analysis. The Computerized Visual Searching Task was used to measure central information processing speed, a common cognitive side effect of AED treatment.

RESULTS

Central information processing speed was lower in patients taking AEDs from the intermediate and high risk categories, compared with patients from the low risk category. The effect of risk category on global efficiency was significant (P < 0.05, ANCOVA), with a significantly higher global efficiency for patient from the low category compared with the high risk category (P < 0.05, post-hoc test). Risk category had no significant effect on the clustering coefficient (ANCOVA, P > 0.2). Also no significant associations between information processing speed and global efficiency or the clustering coefficient (linear regression analysis, P > 0.15) were observed.

CONCLUSION

Only the four patients taking topiramate show aberrant network measures, suggesting that alterations in functional brain network organization may be only subtle and measureable in patients with more severe cognitive side effects.

New Pharmacological Agents to Aid Smoking Cessation and Tobacco Harm Reduction: What Has Been Investigated, and What Is in the Pipeline?

A wide range of support is available to help smokers to quit and to aid attempts at harm reduction, including three first-line smoking cessation medications: nicotine replacement therapy, varenicline and bupropion. Despite the efficacy of these, there is a continual need to diversify the range of medications so that the needs of tobacco users are met. This paper compares the first-line smoking cessation medications with (1) two variants of these existing products: new galenic formulations of varenicline and novel nicotine delivery devices; and (2) 24 alternative products: cytisine (novel outside Central and Eastern Europe), nortriptyline, other tricyclic antidepressants, electronic cigarettes, clonidine (an anxiolytic), other anxiolytics (e.g. buspirone), selective serotonin reuptake inhibitors, supplements (e.g. St John's wort), silver acetate, Nicobrevin, modafinil, venlafaxine, monoamine oxidase inhibitors (MAOIs), opioid antagonists, nicotinic acetylcholine receptor (nAChR) antagonists, glucose tablets, selective cannabinoid type 1 receptor antagonists, nicotine vaccines, drugs that affect gamma-aminobutyric acid (GABA) transmission, drugs that affect N-methyl-D-aspartate (NMDA) receptors, dopamine agonists (e.g. levodopa), pioglitazone (Actos; OMS405), noradrenaline reuptake inhibitors and the weight management drug lorcaserin. Six 'ESCUSE' criteria-relative efficacy, relative safety, relative cost, relative use (overall impact of effective medication use), relative scope (ability to serve new groups of patients) and relative ease of use-are used. Many of these products are in the early stages of clinical trials; however, cytisine looks most promising in having established efficacy and safety with low cost. Electronic cigarettes have become very popular, appear to be efficacious and are safer than smoking, but issues of continued dependence and possible harms need to be considered.

Long-term safety and sustained efficacy of USL255 (topiramate extended-release capsules) in patients with refractory partial-onset seizures

OBJECTIVE

The aim of this study was to evaluate long-term safety, efficacy, and quality of life (QOL) of ≤400-mg/day USL255, Qudexy® XR (topiramate) extended-release capsules, as adjunctive therapy for partial-onset seizures (POS) in adults.

METHODS

Patients who completed the 11-week double-blind treatment phase of the phase 3 PREVAIL study were eligible to enroll in this 1-year open-label extension (OLE) study (PREVAIL OLE). The primary objective was to evaluate the safety and tolerability of USL255 (including treatment-emergent adverse events [TEAEs]). The secondary objective was to assess seizure frequency in patients (e.g., median percent reduction from baseline in weekly POS frequency, responder rate [proportion of patients with ≥25%, ≥50%, ≥75%, or 100% reduction from baseline in POS frequency], and seizure-free intervals [proportion of patients who were seizure-free for 4, 12, 24, 36, or 48weeks]). Exploratory clinical-status endpoints included the Global Impression of Change (CGI-C) and Quality of Life in Epilepsy-Problems (QOLIE-31-P) questionnaires. Post hoc analyses evaluated neurocognitive TEAE incidences during the first 11 and entire 55weeks of treatment and efficacy by patient age and drug-resistant status.

RESULTS

Of the 217 patients who completed PREVAIL (USL255, n=103; placebo, n=114), 210 (97%) enrolled in PREVAIL OLE and were included in the ITT population. Across the entire 55-week treatment period, USL255 was generally safe and well tolerated, with low individual neurocognitive TEAE incidences. Seizure reduction was sustained across the year-long study and observed in patient subgroups, including those with highly drug-resistant seizures and those ≥50years of age. Improvements in CGI-C and QOLIE-31-P were also observed.

SIGNIFICANCE

The results of PREVAIL OLE are consistent with those from PREVAIL and demonstrate that adjunctive treatment with up to 400mg/day of USL255 may be a safe and effective treatment option for a variety of adult patients with refractory POS.

Systematic Adverse Drug Reaction Monitoring of Patients Under Newer Antiepileptic Drugs Using Routine Clinical Data of Inpatients

BACKGROUND

Based on data of clinical trials, new agents are receiving approval to the pharmaceutical market, for which information concerning safety issues under real-life conditions is not yet available.

OBJECTIVES

The aim was to evaluate the tolerability of newer antiepileptic drugs (AEDs), such as topiramate, levetiracetam, zonisamide, pregabalin, extended-release oxcarbazepine, lacosamide and eslicarbazepine, under real-life conditions by means of an assessment of routine clinical data of inpatients.

METHOD

Over 2.75 years data of all inpatients receiving one of the newer AEDs were documented. Occurring adverse drug reactions (ADRs) were classified according to the WHO-UMC Causality Assessment concerning their likely relationship to the prescribed AEDs. For each AED, the total number of patients without and with ADRs, assessed as at least possibly related to the particular drug, was calculated and corresponding incidences compared with reference data provided in the Summary of Product Characteristics (SmPC). For statistical evaluation Spearman correlation (rs), estimated relative risk and logistic regression analysis were used.

RESULTS

In total, the data of 562 patients were assessed, of which 90 % received up to six different AEDs. The proportion of off-label use with regard to dosage varied between 6.4 and 64.7 %. Levetiracetam and oxcarbazepine as an extended-release formulation were most commonly used, and levetiracetam showed the best tolerance. By using logistic regression, the occurrence of ADRs was significantly associated with the number of AEDs (p < 0.001) as well as the defined daily doses (p = 0.003). In total, ADRs of AEDs were documented for 318 patients (56.6 %). The most common referred to electrolyte imbalance, e.g., low sodium (n = 79, 14.1 %) and potassium (n = 25, 4.4 %) levels, the central nervous system, including dizziness (n = 61, 10.9 %), disturbed vision (n = 47, 8.4 %), fatigue (n = 40, 7.1 %), nystagmus (n = 36, 6.4 %) and ataxia (n = 29, 5.2 %), or cognitive deficits, especially disturbance of speech (n = 37, 6.6 %), memory impairment (n = 36, 6.4 %) and mental slowing (n = 32, 5.7 %). By comparing the assessed ADR incidences with specification data, for some ADRs, a probable underestimation by the SmPC of respective risk could be assumed.

CONCLUSION

During inpatient treatment, valuable data are generated, which are currently rarely utilized for pharmacoepidemiologic or pharmacovigilance purposes. A systematic evaluation of these data can increase the probability of detecting ADRs and can promote real-life-related drug surveillance.

Assessment of cognitive safety in clinical drug development

Cognitive impairment is increasingly recognised as an important potential adverse effect of medication. However, many drug development programmes do not incorporate sensitive cognitive measurements. Here, we review the rationale for cognitive safety assessment, and explain several basic methodological principles for measuring cognition during clinical drug development, including study design and statistical analysis, from Phase I through to postmarketing. The crucial issue of how cognition should be assessed is emphasized, especially the sensitivity of measurement. We also consider how best to interpret the magnitude of any identified effects, including comparison with benchmarks. We conclude by discussing strategies for the effective communication of cognitive risks.

Understanding idiopathic intracranial hypertension: mechanisms, management, and future directions

Idiopathic intracranial hypertension is a disorder characterised by raised intracranial pressure that predominantly affects young, obese women. Pathogenesis has not been fully elucidated, but several causal factors have been proposed. Symptoms can include headaches, visual loss, pulsatile tinnitus, and back and neck pain, but the clinical presentation is highly variable. Although few studies have been done to support evidence-based management, several recent advances have the potential to enhance understanding of the causes of the disease and to guide treatment decisions. Investigators of the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT) reported beneficial effects of acetazolamide in patients with mild visual loss. Studies have also established weight loss as an effective disease-modifying treatment, and further clinical trials to investigate new treatments are underway. The incidence of idiopathic intracranial hypertension is expected to increase as rates of obesity increase; efforts to reduce diagnostic delays and identify new, effective approaches to treatment will be key to meeting the needs of a growing number of patients.

Zonisamide Reduces Withdrawal Symptoms But Does Not Enhance Varenicline-Induced Smoking Cessation

INTRODUCTION

Varenicline (Chantix) is a first-line treatment for smoking cessation but does not produce cessation in many individuals. It may be possible to improve abstinence by co-administering varenicline with other medications. Zonisamide (Zonegran) has a similar pharmacologic profile to topiramate, which has been shown to reduce smoking, but is better tolerated. This study evaluated whether combined zonisamide and varenicline reduced tobacco withdrawal and increased abstinence among smokers trying to quit, relative to varenicline and placebo.

METHODS

This was a double-blind, randomized, placebo-controlled pilot trial of zonisamide + varenicline versus placebo + varenicline for smoking cessation. Smokers received brief counseling and study medications, and completed weekly assessments for 10 consecutive weeks. The primary outcome was continuous abstinence rates (biochemically verified) during the final 4 weeks of treatment.

RESULTS

Results are presented as intent-to-treat and completer analyses. Seventy-four individuals were enrolled; 45 completed the study. Overall, 14.9% (intent-to-treat) and 25.0% (completer) of participants maintained sustained abstinence during the final 4 weeks of treatment. There were no differences between groups for biochemically-verified smoking, but zonisamide + varenicline reduced self-reported smoking, nicotine withdrawal, and craving compared to placebo + varenicline.

CONCLUSIONS

Zonisamide decreased nicotine withdrawal and craving, though not of sufficient magnitude to modify smoking behavior. The sample size was small and low rates of abstinence across groups suggest the study population was difficult to treat. Additional evaluation of zonisamide or other medications that increase GABA or decrease glutamate in larger or more diverse populations may yield positive clinical benefit for nicotine/tobacco cessation.

IMPLICATIONS

This study provides support for layering novel medications with varenicline for smoking cessation, for investigating medications that target the GABA and glutamate system, and for assessing the contribution that reductions in nicotine withdrawal have on ultimate cessation outcomes.

A Common Polymorphism in SCN2A Predicts General Cognitive Ability through Effects on PFC Physiology

Here we provide novel convergent evidence across three independent cohorts of healthy adults (n = 531), demonstrating that a common polymorphism in the gene encoding the α2 subunit of neuronal voltage-gated type II sodium channels (SCN2A) predicts human general cognitive ability or "g." Using meta-analysis, we demonstrate that the minor T allele of a common polymorphism (rs10174400) in SCN2A is associated with significantly higher "g" independent of gender and age. We further demonstrate using resting-state fMRI data from our discovery cohort (n = 236) that this genetic advantage may be mediated by increased capacity for information processing between the dorsolateral PFC and dorsal ACC, which support higher cognitive functions. Collectively, these findings fill a gap in our understanding of the genetics of general cognitive ability and highlight a specific neural mechanism through which a common polymorphism shapes interindividual variation in "g."

Cognitive dysfunction in patients with epilepsy: focus on clinical variables

ABSTRACT 

A variety of factors can affect cognitive functions in patients with epilepsy, with the majority of cognitive problems having a multifactorial origin. In routine clinical practice, it can be difficult to dissect out the contribution of all of the different variables, because they are often interlinked together. In this article, all of the major variables implicated in cognitive dysfunction in epilepsy are discussed. In general terms, it is widely accepted that cognitive dysfunction in epilepsy can be trait dependent or state dependent. The former is a permanent condition due to the underlying brain damage or disorder, while the latter is a potentially reversible condition due to modifiable factors, such as antiepileptic drugs, seizure frequency and pattern and psychiatric comorbidity. Neuropsychological deficits also represent an important sequela in epilepsy surgery. Visual naming and visual memory loss have been clearly associated with temporal lobe surgery. It seems that the laterality of resection is not a major determinant, while the extension of resection is relevant for visual naming.