Behaviour, cognition and epilepsy

The significance of interictal electroencephalogram analysis based on the grand total electroencephalogram score in early assessment of cognitive impairment in epilepsy patients

PURPOSE

Epilepsy is a widespread neurological disorder that increases the risk of cognitive impairment (CI) or dementia. We aimed to assess the relationship between cognition and interictal electroencephalogram (EEG) in epilepsy patients, using the Grand Total EEG (GTE) score. Additionally, we investigated the GTE score's utility in the early detection of CI in these patients.

METHODS

Data from 93 patients diagnosed with unexplained epilepsy at the Affiliated Hospital of Yangzhou University were analyzed. EEG recordings and cognitive evaluations were performed. Patients were categorized into three groups based on their Montreal Cognitive Assessment (MoCA) scores: normal cognitive (NC) group, mild cognitive impairment (MCI) group, and dementia group. The study included analysis of correlations between cognitive test results and clinical characteristics. Additionally, the influence of GTE scores and subscores on cognition was examined. Statistical analyses included one-way analysis of variance (ANOVA), Kruskal-Wallis H-test, Mann-Whitney U-test, Chi-square test, Spearman rank correlation analysis, and multiple linear regression.

RESULTS

(1) There was a significant negative correlation between cognitive test scores and GTE scores. Strong negative correlations were found between cognition (MoCA) and the GTE score (ρ = -0.754, P < 0.001), as well as for the subscores "Diffuse Slow Activity" (ρ = -0.712, P < 0.001), "Frequency of Rhythmic Background Activity" (ρ = -0.490, P < 0.001), and "Paroxysmal Activity" (ρ = -0.565, P < 0.001). (2) Multiple linear regression analysis identified the GTE score, "Diffuse Slow Activity", "Paroxysmal Activity", age, and education as significant predictors of cognitive decline. (3) At a threshold of 4.5, the GTE score effectively differentiated between individuals with and without CI, demonstrating a sensitivity of 73.8 % and a specificity of 93.7 %.

CONCLUSION

The GTE score provides clinically valuable information for the early detection of CI in patients with epilepsy. As CI worsens in epilepsy patients, the GTE score, Diffuse Slow Activity, Frequency of Rhythmic Background Activity, and Paroxysmal Activity increase. Healthcare providers should focus on managing not only seizures but also interictal EEG abnormalities to prevent or mitigate the risk of CI.

Epilepsy is associated with the accelerated aging of brain activity in sleep

Objective

Although seizures are the cardinal feature, epilepsy is associated with other forms of brain dysfunction including impaired cognition, abnormal sleep, and increased risk of developing dementia. We hypothesized that, given the widespread neurologic dysfunction caused by epilepsy, accelerated brain aging would be seen. We measured the sleep-based brain age index (BAI) in a diverse group of patients with epilepsy. The BAI is a machine learning-based biomarker that measures how much the brain activity of a person during overnight sleep deviates from chronological age-based norms.

Methods

This case-control study drew information of age-matched controls without epilepsy from home sleep monitoring volunteers and from non-epilepsy patients with Sleep Lab testing. Patients with epilepsy underwent in-patient monitoring and were classified by epilepsy type and seizure burden. The primary outcomes measured were BAI, processed from electroencephalograms, and epilepsy severity metrics (years with epilepsy, seizure frequency standardized by year, and seizure burden [number of seizures in life]). Subanalyses were conducted on a subset with NIH Toolbox cognitive testing for total, fluid, and crystallized composite cognition.

Results

138 patients with epilepsy (32 exclusively focal and 106 generalizable [focal seizures with secondary generalization]) underwent in-patient monitoring, and age-matched, non-epilepsy controls were analyzed. The mean BAI was higher in epilepsy patients vs controls and differed by epilepsy type: -0.05 years (controls) versus 5.02 years (all epilepsy, p < 0.001), 5.53 years (generalizable, p < 0.001), and 3.34 years (focal, p = 0.03). Sleep architecture was disrupted in epilepsy, especially in generalizable epilepsy. A higher BAI was positively associated with increased lifetime seizure burden in focal and generalizable epilepsies and associated with lower crystallized cognition. Lifetime seizure burden was inversely correlated with fluid, crystallized, and composite cognition.

Significance

Epilepsy is associated with accelerated brain aging. Higher brain age indices are associated with poorer cognition and more severe epilepsy, specifically generalizability and higher seizure burden. These findings strengthen the use of the sleep-derived, electroencephalography-based BAI as a biomarker for cognitive dysfunction in epilepsy.

Epilepsy is more than a simple seizure disorder: Parallels between human and canine cognitive and behavioural comorbidities

Psychiatric and cognitive comorbidities have been known to play a major role in human epilepsy for a long time. People with epilepsy (PWE) frequently express signs of varying psychiatric and cognitive disorders affecting their quality and quantity of life (QoL/QaoL). Over the last few years, research on behavioural comorbidities and their effect on the underlying disease have been performed in canine epilepsy. The following article reviews manifestations of comorbidities in canine epilepsy with an emphasis on patterns of clinical signs and their effects on QoL and QaoL. Cognitive and behavioural alterations in epileptic dogs are mainly represented by fear-/anxiety related behaviour and cognitive impairment (CI). Reduced trainability and altered reactions to daily situations are common results of comorbid changes posing obstacles in everyday life of owners and their dog. In addition, clinical signs similar to attention deficit hyperactivity disorder (ADHD) in humans have been reported. Canine attention-deficit-hyperactivity-disorder-like (c-ADHD-like) behaviour should, however, be evaluated critically, as there are no official criteria for diagnosis of ADHD or ADHD-like behaviour in dogs, and some of the reported signs of c-ADHD-like behaviour could be confused with anxiety-associated behaviour. Many intrinsic and extrinsic factors could potentially influence the development of behavioural and cognitive comorbidities in canine epilepsy. In particular, seizure frequency/severity, signalment and factors concerning disease management, such as pharmacotherapy and nutrition, are closely linked with the presence of the aforementioned comorbid disorders. Further studies of behavioural alterations in epileptic dogs are needed to comprehend the complexity of clinical signs and their multifactorial origin.

Epilepsy is more than a simple seizure disorder: Causal relationships between epilepsy and its comorbidities

This review draws connections between the pathogenesis of canine epilepsy and its most commonly recognised comorbidities: cognitive impairment (CI), attention deficit hyperactivity disorder (ADHD)-like behaviour, fear and anxiety. Uni/bidirectional causalities and the possibility of a common aetiology triggering both epilepsy and the associated diseases are considered. Research on this topic is sparse in dogs, so information has been gathered and assessed from human and laboratory animal studies. Anatomical structures, functional connections, disrupted neurotransmission and neuroinflammatory processes collectively serve as a common foundation for epilepsy and its comorbidities. Specific anatomical structures, especially parts of the limbic system, such as the amygdala and the hippocampus, are involved in generating seizures, as well as cognitive- and behavioural disorders. Furthermore, disturbances in inhibitory and excitatory neurotransmission influence neuronal excitability and networks, leading to underlying brain dysfunction. Functional magnetic resonance imaging (fMRI), interictal epileptiform discharges (IEDs), and electroencephalography (EEG) have demonstrated functional brain connections that are related to the emergence of both epilepsy and its various comorbidities. Neuroinflammatory processes can either cause or be a consequence of seizures, and inflammatory mediators, oxidative stress and mitochondrial dysfunction, can equally evoke mood disorders. The extensive relationships contributing to the development and progression of seizures and comorbid cognitive and behavioural conditions illustrate the complexity of the disease that is epilepsy.

Neurophysiological and neuropsychological parameters in patients with temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common type of localization-related epilepsy (LRE) and has been extensively studied in the field of neuropsychology due to its significant association with cognitive impairments. Cognitive decline has long been recognized as a consequence of this form of epilepsy, with previous studies primarily focusing on neurophysiological measures. In this study, both neurophysiological and neuropsychological factors were analyzed in TLE patients compared to healthy control subjects. The Montreal Cognitive Assessment (MoCA) and Mini Mental State Examination (MMSE) tests were used to assess neuropsychological processes, while cognitive event-related potential (ERPs), particularly P300, were employed to analyze neurophysiological parameters. The study involved 21 TLE patients (mean age = 61.43) and 21 healthy control subjects. The results revealing that TLE patients scored significantly lower, indicating deficits in specific cognitive areas. The study also observed abnormalities in the ERPs, particularly in the assessment of P300 amplitude and latency, that may be indicative of underlying neural dysfunction related to attention and cognitive processing. In conclusion, the study provides compelling evidence of the association between TLE and a high incidence of cognitive deficits and decline. By considering both neurophysiological and neuropsychological factors, the study sheds light on the comprehensive impact of TLE on various cognitive domains and emphasizes the importance of early identification and management of cognitive impairments in TLE patients.

The Discordance between Network Excitability and Cognitive Performance Following Vigabatrin Treatment during Epileptogenesis

Vigabatrin (VGB), a potent selective γ-aminobutyric acid transaminase (GABA-T) inhibitor, is an approved non-traditional anti-seizure drug for patients with intractable epilepsy. Nevertheless, its effect on epileptogenesis, and whether this effect is correlated with post-epileptogenic cognitive function remain unclear. Based on lithium-pilocarpine-induced seizure modeling, we evaluated the effect of VGB on epileptogenesis and neuronal damage following status epilepticus in Sprague-Dawley rats. Cognitive evaluations were performed with the aid of inhibitory avoidance testing. We found that VGB could interrupt epileptogenesis by reducing spontaneous recurrent seizures, hippocampal neuronal damage, and chronic mossy fiber sprouting. Nevertheless, VGB did not help with the retention of cognitive performance. Our findings suggest that further research into the role of VGB in epileptogenesis and the treatment of epilepsy in clinical practice is warranted.

Neurocognitive Effects of Antiseizure Medications in Children and Adolescents with Epilepsy

Impairments in cognition are common in epilepsy and may be caused or exacerbated by antiseizure medications (ASMs). Positive effects on cognition may also be seen with some ASMs. Cognitive outcomes are of particular concern in children who may be at an increased risk of cognitive adverse effects of treatment. A comprehensive literature search was conducted in PubMed in order to evaluate the evidence for cognitive changes associated with treatment with ASMs in paediatric epilepsy patients. The ASMs considered were those in the current edition of the British National Formulary (BNF). For most ASMs, remarkably few studies providing robust data on cognitive effects in paediatric patients were identified. The available evidence suggests cognitive impairments may be associated with treatment with phenobarbital. Topiramate and phenytoin are also associated with negative effects on cognition, in particular word-finding difficulties and other language deficits with topiramate, but there are few data available specifically on children. Lamotrigine, levetiracetam and fenfluramine are associated with improvements in some cognitive domains, although it is unclear whether these effects are directly attributable to the medications or are a result of improvements in seizures. Neutral effects on cognition (no substantial evidence of worsening) were suggested for carbamazepine, everolimus, lacosamide, oxcarbazepine, perampanel and valproate. There is limited data for cannabidiol, clobazam, eslicarbazepine acetate, ethosuximide, rufinamide, vigabatrin and zonisamide, although the available evidence suggests these drugs are not associated with severe cognitive impairment. There was too little information to reach conclusions about the effects of brivaracetam, felbamate, gabapentin, pregabalin, retigabine, stiripentol or tiagabine.

Cognitive Dysfunction in Juvenile Myoclonic Epilepsy (JME) - A Tertiary Care Center Study

BACKGROUND AND AIM

Epilepsy often leads to cognitive impairment. Idiopathic generalized epilepsy as a group is considered to be benign in terms of its effects on cognition. Though, neuropsychological testing reveals subtle frontal impairment in patients with juvenile myoclonic epilepsy (JME). The aim of this study is to evaluate cognitive dysfunction in patients with JME.

METHOD

We compared 50 JME patients and 50 age and sex matched healthy controls above 12 years of age on various cognitive tests which included Mini Mental State Examination (MMSE), Frontal Assessment Battery (FAB), Executive Interview (EXIT), PGI Memory Scale (PGIMS), Clock Drawing Test (CDT), Cube copying test (CCT), and Nahor Benson Test (NBT). We correlated the cognitive dysfunction with education level, age of onset, duration of epilepsy, electroencephalogram (EEG) abnormalities, treatment, and seizure control status.

RESULTS

JME patients performed significantly worse on MMSE (P = 0.001), PGI MS (P value = 0.001), FAB (P =.001), EXIT (P =.001), CDT (P =.02), and CCT (P =.001) when compared to the controls. JME patients had impaired attention, verbal fluency, design fluency, verbal memory, visual memory, conceptualization, set shifting, mental flexibility, response inhibition, and visuospatial functions. Cognitive dysfunction correlated with education level, duration of epilepsy and EEG abnormality. No correlation was seen with seizure frequency or type of antiepileptic therapy.

CONCLUSIONS

JME patients demonstrate both frontal and parietooccipital lobe dysfunction. Hence detailed higher mental function tests supplemented by functional neuroimaging studies should be done in JME patients for their comprehensive management. This would also enhance our knowledge about the pathogenesis of JME.

Cognitive impairment in temporal lobe epilepsy: contributions of lesion, localization and lateralization

BACKGROUND

Cognitive impairment is an important comorbidity of refractory temporal lobe epilepsy (TLE). We aimed to explore the impact of (i) specific lesions, such as dysembryoplastic neuroepithelial tumor (DNET), dysplasia, or hippocampal sclerosis, (ii) focus localization (medial versus lateral) and (iii) focus lateralization (right versus left) on the neuropsychological profile of refractory TLE adult patients.

METHODS

We examined the neuropsychological characteristics of 312 adults with refractory TLE: 100 patients without hippocampal sclerosis (HS) and 212 with HS. Scores on tests of intelligence (Global IQ, Verbal IQ and Performance IQ), working memory, episodic memory (verbal and visual learning and forgetting), executive functions and language abilities were analyzed.

RESULTS

Three main factors influenced the neuropsychological profile of refractory TLE patients: (i) the lesion, patients with HS obtaining poorer cognitive performances than patients without HS and specifically DNET patients performing better than patients with HS, (ii) the focus side, that seems only relevant for verbal memory abilities which are affected in left but not right TLE patients and (iii) the localization of seizure focus, patients with medial TLE exhibiting lower memory performances than patients with lateral TLE.

CONCLUSION

Lesion, localization and lateralization are major contributors of the cognitive impairment depicted in TLE. Hippocampal sclerosis appears as the main contributor.

Do interictal EEG findings reflect cognitive function in juvenile myoclonic epilepsy?

PURPOSE

This study investigated the relationship between frontal lobe cognitive function and frontal focal electroencephalography (EEG) findings in patients with juvenile myoclonic epilepsy (JME).

METHODS

The study enrolled 60 patients diagnosed with JME and followed at the Epilepsy Outpatient Clinic of the University of Health Sciences, Bakırkoy Psychiatric Hospital, and 30 healthy volunteers. Demographic and clinical features were recorded. Frontal lobe cognitive functions were tested in both groups. Video-EEG recordings of patients with JME were evaluated. The presence and duration of generalized discharges, the presence and lateralization of focal findings, and the presence of generalized discharges during hyperventilation and photic stimulation were recorded during EEG. Cognitive function test results were compared between the two groups, and the relationship between the EEG findings and cognitive function was investigated.

RESULTS

The study included 35 (58.3%) female and 25 (41.6%) male patients and 17 (56.7%) female and 13 (43.3%) male healthy controls. The mean ages of the group with JME and controls were 28.3 ± 8.6 (16-50) and 31.3 ± 7.9 (17-45) years, respectively. Patients with JME performed more poorly on the frontal lobe cognitive tests than controls (p < 0.05). Patients whose generalized discharges were longer than 1 s performed more poorly on tests evaluating attention and made more perseverative errors (p < 0.05). There was no significant correlation between the presence of focal EEG findings and the scores on frontal lobe cognitive functions tests in the group with JME (p > 0.05).

CONCLUSION

Frontal lobe cognitive functions are affected in patients with JME. The cognitive effects were more pronounced in patients with prolonged generalized discharges on EEG.

Seizure-induced neuroinflammation contributes to ectopic neurogenesis and aggressive behavior in pilocarpine-induced status epilepticus mice

Epilepsy is a chronic neurological disorder often associated with recurrent seizures. A growing body of evidence suggests that seizures cause structural and functional alterations of the brain. It is reported that behavioral abnormalities frequently occur in patients with epilepsy and experimental epilepsy models. However, the precise pathological mechanisms associated with these epilepsy comorbidities remain largely unknown. Neurogenesis persists throughout life in the hippocampal dentate gyrus (DG) to maintain proper brain function. However, aberrant neurogenesis usually generates abnormal neural circuits and consequently causes neuronal dysfunction. Neuroinflammatory responses are well known to affect neurogenesis and lead to aberrant reorganization of neural networks in the hippocampal DG. Here, in this study, we observed a significant increase in neuroinflammation and in the proliferation and survival of newborn granular cells in the hippocampus of pilocarpine-induced status epilepticus (SE) mice. More importantly, these proliferating and surviving newborn granular cells are largely ectopically located in the hippocampal DG hilus region. Our behavior test demonstrated that SE mice displayed severe aggressive behavior. Pharmacological inhibition of neuroinflammation, however, suppressed the ectopic neurogenesis and countered the enhanced aggressive behavior in SE mice, indicating that seizure-induced neuroinflammation may contribute to ectopic neurogenesis and aggressive behavior in SE mice. These findings establish a key role for neuroinflammation in seizure-induced aberrant neurogenesis and aggressive behavior. Suppressing neuroinflammation in the epileptic brain may reduce ectopic neurogenesis and effectively block the pathophysiological process that leads to aggressive behavior in TLE mice.

Neuroprotective effects and improvement of learning and memory elicited by erythravine and 11α-hydroxy-erythravine against the pilocarpine model of epilepsy

Deficits in cognitive functions are often observed in epileptic patients, particularly in temporal lobe epilepsy (TLE). Evidence suggests that this cognitive decline can be associated with the occurrence of focal brain lesions, especially on hippocampus and cortex regions. We previously demonstrated that the erythrinian alkaloids, (+)-erythravine and (+)-11α-hydroxy-erythravine, inhibit seizures evoked in rats by different chemoconvulsants.

AIMS

The current study evaluated if these alkaloids would be acting in a neuroprotective way, reducing hippocampal sclerosis, and consequently, improving learning/memory performance.

MAIN METHODS

Here we confirmed the anticonvulsant effect of both alkaloids by means of the pilocarpine seizure-induced model and also showed that they enhanced spatial learning of rats submitted to the Morris Water Maze test reverting the cognition deficit. Additionally, immunohistochemistry assays showed that neuronal death and glial activation were prevented by the alkaloids in the hippocampus CA1, CA3 and dentate gyrus regions at both hemispheres indistinctly 15 days after status epilepticus induction.

KEY FINDINGS

Our results show, for the first-time, the improvement on memory/learning elicited by these erythrinian alkaloids. Furthermore, data presented herein explain, at least partially, the cellular mechanism of action of these alkaloids. Together, (+)-erythravine and (+)-11α-hydroxy-erythravine seem to be a promising protective strategy against TLE, comprising three main aspects: neuroprotection, control of epileptic seizures and cognitive improvement.

SIGNIFICANCE

Moreover, our findings on neuroprotection corroborate the view that seizure frequency and severity, hippocampal lesions and memory deficits are interconnected events.

Evaluation of sodium valproate loaded nanoparticles in acute and chronic pentylenetetrazole induced seizure models

BACKGROUND AND PURPOSE

Efficacy of sodium valproate in epilepsy is limited by its poor blood brain barrier penetration and side effects. Nanoparticles may offer a better drug delivery system to overcome these limitations. This study evaluated the efficacy of sodium valproate encapsulated in nanoparticles in pentylenetetrazole (PTZ) induced acute and kindling models of seizures in male Wistar rats.

METHODS

Poly lactic-co-glycolic acid (PLGA) based, polysorbate 80 stabilized sodium valproate loaded nanoparticles (nano sodium valproate) and rhodamine loaded nanoparticles (RLN) were formulated by double emulsion- solvent evaporation method and characterized for their size, shape, zeta potential and drug loading percentage. RLN was used to demonstrate blood brain barrier (BBB) permeability of nanoparticles. Serum drug levels were estimated using high performance liquid chromatography. The efficacy of standard sodium valproate (300 mg/kg) and nano sodium valproate (∼300, ∼150 and ∼75 mg/kg of sodium valproate) were evaluated in experimental animal models of seizures along with their effects on behavioral and oxidative stress parameters. Drugs were administered 60 min before PTZ in acute model. In the kindling model, drugs were administered every day while PTZ was administered on alternate days 60 min after drug administration. All the study drugs/compounds were administered intraperitoneally.

RESULTS

RLN were observed to be clustered in cortex which implied that the nanoparticles crossed BBB. Both standard sodium valproate and nano sodium valproate reached therapeutic serum level at 15 min and 1 h, but were undetectable in serum at 24 h. In acute PTZ (60 mg/kg) model, nano sodium valproate (∼300 mg/kg of sodium valproate) and standard sodium valproate showed protection against seizures till 6 h and 4 h, respectively. There were significant behavioral impairment and oxidative stress with standard sodium valproate in acute model as compared to nano sodium valproate at 6 h. In kindling model, induced with PTZ (30 mg/kg, every alternate day for 42 days), complete protection from seizures was observed with nano sodium valproate (∼150 mg/kg and ∼75 mg/kg of sodium valproate) and standard sodium valproate (300 mg/kg). Similarly, significant protection from behavioral impairment and oxidative stress was observed with standard sodium valproate and nano sodium valproate as compared to PTZ.

CONCLUSION

When compared to conventional therapy, nano sodium valproate showed protection from seizures at reduced doses and for a longer duration in animal models of epilepsy. This study suggests the potential of nano sodium valproate in the treatment of epilepsy.

Neuropsychology Outcomes Following Trephine Epilepsy Surgery: The Inferior Temporal Gyrus Approach for Amygdalohippocampectomy in Medically Refractory Mesial Temporal Lobe Epilepsy

BACKGROUND

Surgery is indicated in cases of mesial temporal lobe epilepsy(MTLE) that are refractory to medical management. The inferior temporal gyrus (ITG) approach provides access to the mesial temporal lobe (MTL) structures with minimal tissue disruption. Reported neuropsychology outcomes following this approach are limited.

OBJECTIVE

To report neuropsychological outcomes using an ITG approach to amygdalohippocampectomy (AH) in patients with medically refractory MTLE based on a prospective design.

METHODS

Fifty-four participants had Engel class I/II outcome following resection of MTL using the ITG approach. All participants had localization-related epilepsy confirmed by long-term surface video-electroencephalography and completed pre/postsurgical evaluations that included magnetic resonance imaging (MRI), Wada test or functional MRI, and neuropsychology assessment.

RESULTS

Clinical semiology/video-electroencephalography indicated that of the 54 patients, 28 (52%) had left MTLE and 26 (48%) had right MTLE. Dominant hemisphere resections were performed on 23 patients (43%), nondominant on 31(57%). Twenty-nine (29) had pathology-confirmed mesial temporal sclerosis (MTS). Group level analyses found declines in verbal memory for patients with language-dominant resections (P < .05). No significant decline in neuropsychological measures occurred for patients with MTS. Participants without MTS who underwent a language-dominant lobe resection exhibited a significant decline in verbal and visual memory (P < .05). Nondominant resection participants did not exhibit significant change in neuropsychology scores (P > .05).

CONCLUSION

Neuropsychology outcomes of an ITG approach for selective mesial temporal resection are comparable to other selective AH techniques showing minimal adverse cognitive effects. These data lend support to the ITG approach for selective AH as an option for MTLE.

Reliable Digit Span: Does it Adequately Measure Suboptimal Effort in an Adult Epilepsy Population?

Objective

Assessment of performance validity is a necessary component of any neuropsychological evaluation. Prior research has shown that cutoff scores of ≤6 or ≤7 on Reliable Digit Span (RDS) can detect suboptimal effort across numerous adult clinical populations; however, these scores have not been validated for that purpose in an adult epilepsy population. This investigation aims to determine whether these previously established RDS cutoff scores could detect suboptimal effort in adults with epilepsy.

Method

Sixty-three clinically referred adults with a diagnosis of epilepsy or suspected seizures were administered the Digit Span subtest of the Wechsler Adult Intelligence Scale (WAIS-III or WAIS-IV). Most participants (98%) passed Trial 2 of the Test of Memory Malingering (TOMM), achieving a score of ≥45.

Results

Previously established cutoff scores of ≤6 and ≤7 on RDS yielded a specificity rate of 85% and 77% respectively. Findings also revealed that RDS scores were positively related to attention and intellectual functioning. Given the less than ideal specificity rate associated with each of these cutoff scores, together with their strong association to cognitive factors, secondary analyses were conducted to identify more optimal cutoff scores. Preliminary results suggest that an RDS cutoff score of ≤4 may be more appropriate in a clinically referred adult epilepsy population with a low average IQ or lower.

Conclusions

Preliminary findings indicate that cutoff scores of ≤6 and ≤7 on RDS are not appropriate in adults with epilepsy, especially in individuals with low average IQ or below.

Bumetanide Prevents Brain Trauma-Induced Depressive-Like Behavior

Brain trauma triggers a cascade of deleterious events leading to enhanced incidence of drug resistant epilepsies, depression, and cognitive dysfunctions. The underlying mechanisms leading to these alterations are poorly understood and treatment that attenuates those sequels are not available. Using controlled-cortical impact as an experimental model of brain trauma in adult mice, we found a strong suppressive effect of the sodium-potassium-chloride importer (NKCC1) specific antagonist bumetanide on the appearance of depressive-like behavior. We demonstrate that this alteration in behavior is associated with an impairment of post-traumatic secondary neurogenesis within the dentate gyrus of the hippocampus. The mechanism mediating the effect of bumetanide involves early transient changes in the expression of chloride regulatory proteins and qualitative changes in GABA(A) mediated transmission from hyperpolarizing to depolarizing after brain trauma. This work opens new perspectives in the early treatment of human post-traumatic induced depression. Our results strongly suggest that bumetanide might constitute an efficient prophylactic treatment to reduce neurological and psychiatric consequences of brain trauma.

Cognitive benefits of the ketogenic diet in patients with epilepsy: A systematic overview

The ketogenic diet (KD) has been found to be effective in reducing seizures in patients with treatment-refractory epilepsy. Less attention has been paid to additional cognitive benefits of KD. The aim of the present paper was to provide a comprehensive overview of the studies reporting effects on cognition after KD treatment in adults and children with epilepsy. To address this aim, the clinical literature on cognitive effects of KD in patients with epilepsy was reviewed using a systematic approach. We conclude that using subjective assessments of the patient's experience, cognitive improvements are frequently reported during KD treatment in the domains of alertness, attention, and global cognition. Studies that used objective neuropsychological tests confirmed benefits on alertness but found no improvement in global cognition. There are indications that these improvements are caused by both seizure reduction and direct effects of KD on cognition. The improvements appear to be unrelated to medication reduction, age when KD is started, type of KD, and sleep improvement. The findings in the present overview contribute to a better understanding of the beneficial effects of KD in patients with epilepsy.

Frontal lobe cognitive functions and electroencephalographic features in juvenile myoclonic epilepsy

PURPOSE

The study aimed to examine the relationship between frontal lobe functions and interictal electroencephalography (EEG) discharge characteristics of patients with juvenile myoclonic epilepsy (JME).

METHOD

Thirty patients with JME who had EEG with asymmetrical generalized discharge (aEEG), 15 patients with JME who had EEG with symmetrical generalized discharge (sEEG), and 15 healthy controls were included in the study. To evaluate attention, the digit span and Corsi block tests were used; to evaluate memory, we applied verbal and visual memory tests; to evaluate frontal lobe functions, we used clock drawing, verbal fluency, the Stroop test, trail making, mental control, and antisaccadic eye movement tests as well as the continuous performance (CPT) tests.

ETHICAL CONSIDERATIONS

The research was approved by the Research Ethics Committee of the Bakirkoy Research and Training Hospital for Psychiatry, Neurology, Neurosurgery, with protocol number: 41340010/4891-262, date: 05.02.2013.

RESULTS

The mean age of the 45 patients with JME was 22.89 ± 6.77 years, and 34 (75.6%) were female. The age at onset of seizures and disease duration of the patients with JME was 15.56 ± 4.06 years (range, 9-26 years) and 7.20 ± 5.59 years (range, 1-25 years), respectively. All patients were under valproate (VPA) treatment, and the mean VPA dosage was 783.33 ± 379.14 mg/day. Patients with JME scored worse than the control group in attention, memory, and frontal lobe functions. In patients with aEEG, scores of attention, memory, and frontal lobe function tests were lower than in patients with sEEG; however, with the exception of CPT, they were not statistically significant.

CONCLUSION

Cognitive functions in JME have been shown to be impaired. Furthermore, we concluded that the frontal lobe cognitive functions may be worse in patients with aEEG than in patients with sEEG. Further studies in patients with JME with aEEG abnormalities may lead to a better understanding of the pathophysiology of JME.

Correlation between clinical and cognitive aspects and nutritional indicators of elderly patients with new-onset epilepsy

OBJECTIVE

Nutritional indicators were correlated with cognitive and clinical aspects of 25 elderly patients with new-onset epilepsy (EPWE). The nutritional indicators of the EPWE were compared with those of a similar control group at a significance level of p < 0.05.

RESULTS

There was lower cognitive performance, greater risk of malnutrition and muscle tissue depletion, and higher waist circumference (WC) in the EPWE. Longer epilepsy duration was correlated with loss of muscle mass (Pearson's correlation: 0.433; p = 0.044). Performance in the verbal fluency test, in the clock-drawing test, and in the immediate memory test was negatively associated with body fat. Better performance in the image recognition test was negatively associated with the indicators of muscle reserve.

CONCLUSION

There was lower cognitive performance, higher risk of malnutrition, and high abdominal obesity in EPWE. Cognitive performance was related to adiposity. Cognitive impairment and longer disease duration are related to increased nutritional risk.

Chronic treatment with the new anticonvulsant drug lacosamide impairs learning and memory processes in rats: A possible role of BDNF/TrkB ligand receptor system

Cognitive impairment is considered a frequent side effect in the drug treatment of epilepsy. The objective of the present study was to investigate the effects of lacosamide (LCM) on learning and memory processes in rats, on the serum level of brain-derived neurotrophic factor (BDNF) and BDNF/TrkB ligand receptor system expression in the hippocampal formation. Male Wistar rats underwent long-term treatment with three different doses of lacosamide - 3 mg/kg (LCM 3), 10 mg/kg (LCM 10) and 30 mg/kg (LCM 30). All rats were subjected to one active and one passive avoidance tests. The BDNF/TrkB immunohistochemical expression in the hippocampus was measured and serum BDNF was determined. The LCM-treated rats made fewer avoidance responses than controls during acquisition training and in the memory retention test. The number of escapes in the LCM 10 and LCM 30 groups decreased throughout the test, while the rats in the LCM 3 group showed fewer escapes only in the memory test in the active avoidance task. In the step-down test, the latency time of the LCM-30 treated rats was reduced as compared with the controls during the learning session and the short- and long-term memory retention tests. Lacosamide induced a dose-dependent reduction of the hippocampal expression of BDNF and its receptor TrkB. We found no significant difference between BDNF serum levels in the test animals and controls. The results of the study suggest that LCM suppresses the learning and memory processes in rats, with the inhibition of hippocampal BDNF/TrkB ligand receptor system being one of the possible mechanisms causing this effect.

Accuracy of WISC-III and WAIS-IV short forms in patients with neurological disorders

The assessment of intellectual abilities is intensive, time-consuming, and might be considered burdensome for patients. We examined psychometric qualities of short forms (SFs) of the Wechsler Intelligence Scales for Children (WISC-third edition) and for adults (WAIS-fourth edition), in children (n = 986; M_age = 10.9) and adults (n = 324; M_age = 40.9) with neurological disorders. SF estimates were compared with Full Scale IQ (FSIQ), obtained by a complete administration, for the entire sample and for the subgroups FSIQ < 80 and FSIQ ≥ 80. The FSIQ was correctly identified within ± 7 points in 86% of children and 87% of adults. There were, however, some differences regarding the optimal SF subtest combination between subgroups. Although clinical inferences should not be made, SFs may be useful in research settings to obtain a global estimate of intelligence, and in clinical settings to screen periodically for possible intellectual deterioration.

Neurocognitive problems in epilepsy

Cognitive dysfunction is one of the major contributors to the burden of epilepsy. It can significantly disrupt intellectual development in children and functional status and quality of life in adults. Epilepsy affects cognition through a number of mechanisms in complex interrelationship. Cognitive deficits in epilepsy may be treated indirectly through aggressive seizure control using anti-epileptic drugs or surgery, and by treating comorbid conditions such as depression. The beneficial effects of reducing seizures may offset the adverse cognitive side-effects of these therapies. Direct treatment of cognitive impairment in epilepsy mainly involves memory rehabilitation. Other direct treatments are mostly experimental and their evidence base is currently poor.

Autism spectrum disorder phenotype and intellectual disability in females with epilepsy and PCDH-19 mutations

INTRODUCTION

Autism features and various degrees of cognitive deficit are reported in patients with PCDH-19 mutations and epilepsy. Autism spectrum disorder (ASD) and, often, cognitive profile are usually assessed clinically. We studied autism phenotype and cognitive outcome in a series of patients using standardized tools for development and ASD. We aimed to describe the phenotype of ASD in this series and to understand whether ASD is strictly linked to intellectual disability (ID) or is present as a comorbidity.

METHODS

Eight females aged 5 to 17years old with PCDH-19 mutations and epilepsy were recruited. For ASD diagnosis, the Autism Diagnostic Interview - Revised (ADI-R) and the Autism Diagnosis Observation Schedule (ADOS) were administered. Patients underwent a neuropsychological examination with tests measuring global intellectual efficiency (WPPSI-III and WISC-IV), language, and executive and social cognition abilities. Parental adaptive behavioral questionnaires were also obtained (VABS, CBCL, and BRIEF).

RESULTS

Six out of eight patients presented with ASD and ID. Two patients had neither ASD nor ID, and both had the latest age of onset for their epilepsy. All cognitive functions were deficient, but theory-of-mind abilities compared to other cognitive features were even impaired. Features of ASD lacked major repetitive and stereotyped behaviors and show some differences with the classical ASD features related to ID.

CONCLUSION

Our results show a large spectrum of ID and a very high rate of ASD in patients with epilepsy and PCDH-19 mutations. Autism spectrum disorder seems to be a genuine comorbidity, more than a consequence of ID. It highlights the importance of standardized psychiatric and cognitive evaluation in order to establish a tailored rehabilitation program.

A systematic review of neuropsychiatric comorbidities in patients with both epilepsy and intellectual disability

Epilepsy is a neurological condition that is particularly common in people with intellectual disability (ID). The care for people with both epilepsy and ID is often complicated by the presence of neuropsychiatric disorders, defined as psychiatric symptoms, psychiatric disorders, and behavioral problems. The aim of this study was to investigate associations between epilepsy or epilepsy-related factors and neuropsychiatric comorbidities in patients with ID and between ID and neuropsychiatric comorbidities in patients with epilepsy. We performed a systematic review of the literature, published between January 1995 and January 2015 and retrieved from PubMed/Medline, PsycINFO, and ERIC and assessed the risk of bias using the SIGN-50 methodology. Forty-two studies were identified, fifteen of which were assessed as having a low or acceptable risk-of-bias evaluation. Neuropsychiatric comorbidities were examined in relation to epilepsy in nine studies; in relation to epilepsy-related factors, such as seizure activity, seizure type, and medication in four studies; and in relation to the presence and degree of ID in five studies. We conclude that the presence of epilepsy only was not a clear determinant of neuropsychiatric comorbidity in patients with ID, although a tendency towards negative mood symptoms was identified. Epilepsy-related factors indicating a more severe form of epilepsy were associated with neuropsychiatric comorbidity as was the presence of ID as compared to those without ID in patients with epilepsy, although this should be validated in future research. A large proportion of the studies in this area is associated with a substantial risk of bias. There is a need for high quality studies using standardized methods to enable clear conclusions to be drawn that might assist in improving the quality of care for this population.

Biomedical risk, psychosocial influences, and developmental outcomes: lessons from the pediatric HIV population in Africa

Sub-Saharan Africa is home to millions of HIV-affected children. These children are likely to experience multiple developmental delays. In this chapter, I present data highlighting compromised neurobehavioral, mental health, and scholastic outcomes for children affected by HIV. Furthermore, I discuss biomedical factors (e.g., disease severity and nutritional status) that may exacerbate the adverse effects of HIV on childhood outcomes. I also present evidence on how psychosocial risk factors such as poor maternal mental health, orphanhood, and poverty may aggravate the effects of HIV. The concluding section of the chapter highlights conceptual and methodological refinements in research on the impact of HIV on child development in Sub-Saharan Africa.

Cognition and behavior in a prevalent cohort of children with epilepsy in rural northern Tanzania: A three-year follow-up study

OBJECTIVES

Eighty-five percent of the 33 million children with epilepsy (CWE) worldwide live in low- and middle-income countries (LMICs). There is limited research into epilepsy-related comorbidities in LMICs, and there are no studies of the long-term progression of behavioral and intellectual difficulties in childhood epilepsy in sub-Saharan Africa. We aimed to assess behavior and cognition at three-year follow-up in CWE in rural Tanzania.

METHODS

In 2010, a cross-sectional study identified 112 CWE 6 to 14years of age and 113 age- and sex-matched controls in the Hai district of northern Tanzania. From March to June 2013, cases and controls (now 10 to 18years of age) were followed up. At baseline, behavior was assessed using the Rutter A Questionnaire and cognition using the Goodenough-Harris Drawing Test. Details of current seizure frequency and antiepileptic drug (AED) use among CWE were collected.

RESULTS

At follow-up, cases had significantly more behavioral difficulties compared with controls (48% of 108 cases versus 14% of 103 controls (p<0.001)). Additionally, 69% of the cases and 16% of the controls had cognitive impairment (p<0.001). In CWE with decreased seizure frequency from baseline to follow-up, behavior had improved significantly. At follow-up, there was no significant difference in behavior between CWE with decreased seizure frequency and those with good seizure control throughout.

SIGNIFICANCE

Behavioral difficulties and cognitive impairment are common among CWE in this population. Improved access to AED treatment and subsequent improved seizure control may reduce the frequency of behavioral difficulties seen in this population.

The relevance of neuropsychiatric symptoms and cognitive problems in new-onset epilepsy - Current knowledge and understanding

Neurobehavioral and cognition problems are highly prevalent in epilepsy, but most research studies to date have not adequately addressed the precise nature of the relationship between these comorbidities and seizures. To address this complex issue and to facilitate collaborative, innovative research in the rising field of neurobehavioral comorbidities and cognition disturbances in new-onset epilepsy, international epilepsy experts met at the 3rd Halifax International Epilepsy Conference & Retreat at White Point, South Shore, Nova Scotia, Canada from September 18 to 20, 2014. This Conference Proceedings provides a summary of the conference proceedings. Specifically, the following topics are discussed: (i) role of comorbidities in epilepsy diagnosis and management, (ii) role of antiepileptic medications in understanding the relationship between epilepsy and neurobehavioral and cognition problems, and (iii) animal data and diagnostic approaches. Evidence to date, though limited, strongly suggests a bidirectional relationship between epilepsy and cognitive and psychiatric comorbidities. In fact, it is likely that seizures and neurobehavioral problems represent different symptoms of a common etiology or network-wide disturbance. As a reflection of this shared network, psychiatric comorbidities and/or cognition problems may actually precede the seizure occurrence and likely get often missed if not screened.

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.

Atherosclerosis in epilepsy: its causes and implications

Evidence from epidemiological, longitudinal, prospective, double-blinded clinical trials as well as case reports documents age-accelerated atherosclerosis with increased carotid artery intima media thickness (CA-IMT) in patients with epilepsy. These findings raise concern regarding their implications for age-accelerated cognitive and behavioral changes in midlife and risk of later age-related cognitive disorders including neurodegenerative processes such as Alzheimer's disease (AD). Chronic epilepsy, cerebral atherosclerosis, and age-related cognitive disorders including AD share many clinical manifestations (e.g. characteristic cognitive deficits), risk factors, and structural and pathological brain abnormalities. These shared risk factors include increased CA-IMT, hyperhomocysteinemia (HHcy), lipid abnormalities, weight gain and obesity, insulin resistance (IR), and high levels of inflammatory and oxidative stresses. The resulting brain structural and pathological abnormalities include decreased volume of the hippocampus, increased cortical thinning of the frontal lobe, ventricular expansion and increased white matter ischemic disease, total brain atrophy, and β-amyloid protein deposition in the brain. The knowledge that age-accelerated atherosclerosis may contribute to age-accelerated cognitive and behavioral abnormalities and structural brain pathologies in patients with chronic epilepsy represents an important research path to pursue future clinical and management considerations.

What is important in rehabilitation for persons with epilepsy? Experiences from focus group interviews with patients and staff

This study aimed to identify the issues experienced as essential in rehabilitation for persons with epilepsy. Six focus group interviews were conducted, five groups with patients that had completed comprehensive rehabilitation for persons with epilepsy, in a day-care setting, at the Neurological Rehabilitation Clinic at Stora Sköndal Hospital, between 2006 and 2009 (total n=17) and one group with staff members (n=5). Using content analysis, two themes emerged: life with epilepsy and rehabilitation experiences. The result emphasizes that rehabilitation for persons with epilepsy should be designed individually, in structure and in content. Encounters between patients were important, as well as the team's attitude in meeting with the patients. Therapeutic working alliance is essential between patients and staff for creating an individual rehabilitation.

Antiepileptic drugs prescription utilization behavior and direct costs of treatment in a national hospital of India

Background and Objectives:

The present study evaluated the direct costs of active epilepsy and looked at the pattern of drug prescription and utilization in epileptic patients visiting the neuroscience centre of a national hospital of India.

Materials and Methods:

A total of 134 epileptic patients were studied over a period of 4 months. Patients demography, commonly prescribed antiepileptic drugs (AEDs), socioeconomic status, direct costs, response ratio (RR) for newer drugs, and quality of life (QOLIE-10) was evaluated.

Results and Discussion:

We found a higher percentage of male patients (67.9%) as compared with females. Most of the patients were in the age group 11–30 years and majority of them (39.6%) belonged to lower middle group. A higher percentage (68.7) of drugs was prescribed as polytherapy. Higher monthly cost was observed for some of the newer AEDs including the lamotrigine, levetiracetam, and lacosamide as compared with older drugs. Among the newer drugs, clobazam had the lowest cost. RR was calculated for 12 patients out of which 8 had a RR < –0.50. The QOL domains, following conventional or newer drugs, were not much affected.

Conclusion:

The study indicates an increasing trend toward clinical usage of newer AEDs, increasing trend of poly-therapy with significant escalations in the cost of therapy.

Long-term follow-up after comprehensive rehabilitation of persons with epilepsy, with emphasis on participation in employment or education

The objective of this study was to describe the current situation of patients with epilepsy after rehabilitation with emphasis on employment and education and to investigate if clinical factors at admission were associated with increase in employment or education. All patients that participated in a comprehensive rehabilitation were eligible. Data were collected from medical records at admission, during rehabilitation, at discharge and from a structured telephone interview at follow-up 1-17 years after admission. In total, 124 patients participated in the follow-up. Participation in employment or education improved from admission to follow-up in 38 patients. In univariable analysis, active epilepsy with tonic-clonic seizures at admission was significantly associated with increased participation in employment or education at follow-up, so was decreased frequency of tonic-clonic seizures from admission to follow-up. The significance of the associations disappeared in adjusted multivariable analysis. Participation in employment or education was improved for many patients at follow-up.

Cognitive dysfunction in people with convulsive seizures in rural China

One hundred and forty-four people with convulsive seizures (CS) and 144 healthy controls were evaluated for cognitive function, using a battery of neuropsychological tests. People with CS performed significantly worse than the controls on the Mini-Mental State Examination, Hamilton Depression Rating Scale, auditory verbal learning test, digit span test, verbal fluency test, and digit cancellation test. The percentage of patients who had abnormal scores on the Hamilton Depression Rating Scale was higher than that of controls (54.9% vs. 7.6%, p<0.001). Cognitive functional impairment was detected in 65.3% of the patients and 29.2% of the controls (p<0.001). People with CS presented with depressive mood and a wide range of cognitive deficits, particularly deficits in episodic declarative memory, attentional capacity, semantic memory, and mental speed. Years in education were positively associated with the cognitive performance of people with CS (OR=0.655, 95% CI: 0.486-0.882, p=0.005).

A mechanistic appraisal of cognitive dysfunction in epilepsy

A strong relationship between the clinical characteristics of epilepsy and the nature of cognitive impairments associated with the condition has been found, but the nature of this relationship appears to be quite complex and not well understood. This review presents a summary of the research on the interaction between cognition and epilepsy, surveyed from a mechanistic perspective with the aim of clarifying factors that contribute to the co-existence of both disorders. The physiological basis underpinning cognitive processing is first reviewed. The physiology of epilepsy is reviewed, with emphasis placed on interictal discharges and seizures. The nature of the impact of epilepsy on cognition is described, with transient and prolonged effects distinguished. Finally, the complexity of the co-morbidity between cognitive dysfunction and epilepsy is discussed in relation to childhood and adult-onset epilepsy syndromes and severe epileptic encephalopathies. Structural and functional abnormalities exist in patients with epilepsy that may underpin both the cognitive dysfunction and epilepsy, highlighting the complexity of the association. Research, possibly of a longitudinal nature, is needed to elucidate this multifactorial relationship between cognitive dysfunction and epilepsy.

Changes in memory function in children and young adults with temporal lobe epilepsy: a follow-up study

This longitudinal study explored change in memory function from childhood to young adulthood in temporal lobe epilepsy (TLE). The 24 participants (11 left TLE; 13 right TLE) had a mean age of 16.10 years (SD=4.13 years), and 14 had undergone surgery since initial assessment. Contrary to baseline, verbal memory deficits were lateralized (left<right on paired associate learning, p=.009, and delay, p=.02). Change over time interacted with laterality on a complex non-verbal memory task (p=.05), with the right but not the left group improving. A three-way time-by-laterality-by-surgery interaction was significant for delayed facial recognition (p=.05), with surgical groups improving irrespective of laterality. Non-surgical groups remained stable, although there was a trend for the right to improve and the left to decline. Results were independent of seizure variables, mood and IQ and suggest that memory in left TLE tends to remain stable over time and improve in right TLE.

Behavioral problems in children with epilepsy in rural Kenya

The aims of this study were to record behavioral problems in children with epilepsy (CWE), compare the prevalence with that reported among healthy children without epilepsy, and investigate the risk factors. A child behavioral questionnaire for parents comprising 15 items was administered to the main caregiver of 108 CWE and 108 controls matched for age in Kilifi, Kenya. CWE had a higher mean score for reported behavioral problems than controls (6.9 vs 4.9, t=4.7, P<0.001). CWE with active epilepsy also recorded more behavioral problems than those with inactive epilepsy (8.2 vs 6.2, t=-2.9, P=0.005). A significantly greater proportion of CWE (49% vs 26% of controls) were reported to have behavioral problems. Active epilepsy, cognitive impairment, and focal seizures were the most significant independent covariates of behavioral problems. Behavioral problems in African CWE are common and need to be taken into consideration in planning comprehensive clinical services in this region.

Future directions in the neuropsychology of epilepsy

Two important themes for future clinical research in the neuropsychology of epilepsy are proposed: (1) the neurobiological abnormalities that underlie neuropsychological impairment in people with epilepsy, and (2) neuropsychological status of persons with new-onset epilepsy.

Newly diagnosed epilepsy: cognitive outcome after 12 months

PURPOSE

Cognitive impairment is a common comorbidity of epilepsy; however, relatively little research has been undertaken to investigate how cognitive problems develop in adults who are newly diagnosed. This study aimed to investigate changes in cognitive performance in adults with new-onset epilepsy 12 months after diagnosis compared with healthy volunteers.

METHODS

One hundred forty-seven people with epilepsy (PWE) were assessed using a comprehensive neuropsychological test battery before they started treatment and after 12 months. Cognitive change scores were compared with 69 healthy volunteers who were also assessed at baseline and after 12 months.

KEY FINDINGS

At 12 month follow-up, PWE had significantly poorer change scores for 9 of the 16 variables. For the majority of these measures, PWE had subtle declines in performance, whereas healthy volunteers improved. Poorer performance on some measures was associated with treatment with topiramate, generalized seizures and, interestingly, achieving an immediate 12-month seizure remission.

SIGNIFICANCE

After controlling for statistically confounding factors, people with newly diagnosed epilepsy had a different cognitive trajectory compared with healthy volunteers from the general population. Memory, psychomotor speed, and higher executive functioning were the domains most vulnerable to change over a 12-month period.

Cognitive and behavioral effects of lamotrigine and carbamazepine monotherapy in patients with newly diagnosed or untreated partial epilepsy

PURPOSE

In this prospective study, we compared the long-term cognitive and behavioral effects of lamotrigine (LTG) and carbamazepine (CBZ) in patients with newly diagnosed or untreated partial epilepsy.

METHODS

This was a multicenter, open-label, randomized study that compared monotherapy with LTG and CBZ in newly diagnosed or untreated patients with partial epilepsy. We employed an 8-week titration period and a 40-week maintenance period. Neuropsychological tests, Symptom Check List-90, and QOLIE-31 were assessed at baseline, 16 weeks, and 48 weeks after drug treatment. A group-by-time interaction was the primary outcome measure and was analyzed by use of the linear mixed model.

RESULTS

A total of 110 patients were eligible and 73 completed the 48-week study (LTG, n=39; CBZ, n=34). Among the cognitive tests, significant group-by-time interaction was identified only in phonemic fluency of Controlled Oral Word Association Task (p=0.0032) and Stroop Color-Word Interference (p=0.0283), with a significant better performance for LTG group. All other neuropsychological tests included did not show significant group-by-time interactions. Among the subscales of Symptom Check List-90, significant group-by-time interactions were identified in Obsessive-Compulsive (p=0.0005), Paranoid Ideation (p=0.0454), Global Severity Index (p=0.0194), and Positive Symptom Total (p=0.0197), with a significant improvement for CBZ group. QOLIE-31 did not show significant group-by-time interactions.

CONCLUSION

Our data suggest that epilepsy patients on LTG have better performance on phonemic fluency and the task of Stroop Color-Word Interference than do patients on CBZ, whereas patients on CBZ had more favorable behavioral effects on two subscales and two global scores of Symptom Check List-90 than did patients on LTG.