Psychiatric and behavioral side effects of the newer antiepileptic drugs in adults with epilepsy

Psychiatric and behavioral side effects of antiepileptic drugs in adults with epilepsy

PURPOSE

Psychiatric and behavioral side effects (PBSEs) are common, undesirable effects associated with antiepileptic drug (AED) use. The objective of the study was to compare the PBSE profiles of older and newer AEDs in a large specialty practice-based sample of patients diagnosed with epilepsy.

METHODS

As part of the Columbia and Yale AED Database Project, we reviewed patient records including demographics, medical history, AED use, and side effects for 4085 adult patients (age: 18 years) newly started on an AED regimen. Psychiatric and behavioral side effects were determined by patient or physician report in the medical record, which included depressive mood, psychosis, anxiety, suicidal thoughts, irritability, aggression, and tantrum. Significant non-AED predictors of PBSE rate were first determined from 83 variables using logistic regression. Predictors were then controlled for in the comparison analysis of the rate of PBSEs and intolerable PBSEs (PBSEs that led to dosage reduction or discontinuation) between 18 AEDs.

RESULTS

Psychiatric and behavioral side effects occurred in 17.2% of patients and led to intolerability in 13.8% of patients. History of psychiatric condition(s), secondary generalized seizures, absence seizures, and intractable epilepsy were associated with increased incidence of PBSE. Levetiracetam (LEV) had the greatest PBSE rate (22.1%). This was statistically significant when compared with the aggregate of the other AEDs (P<0.001, OR=6.87). Levetiracetam was also significantly (P<0.001) associated with higher intolerability rate (17.7%), dose decreased rate (9.4%), and complete cessation rate (8.3%), when compared with the aggregate of the other AEDs. Zonisamide (ZNS) was also significantly associated with a higher rate of PBSE (9.7%) and IPBSE (7.9%, all P<0.001). On the other hand, carbamazepine (CBZ), clobazam (CLB), gabapentin (GBP), lamotrigine (LTG), oxcarbazepine (OXC), phenytoin (PHT), and valproate (VPA) were significantly associated with a decreased PBSE rates (P<0.001). Carbamazepine, GBP, LTG, PHT, and VPA were also associated with lower IPBSE rates when compared individually with the aggregate of other AEDs. All other AEDs were found to have intermediate rates that were not either increased or decreased compared with other AEDs. When each AED was compared to LTG, only CBZ had a significantly lower PBSE rate. The main limitations of this study were that the study design was retrospective and not blinded, and the AEDs were not randomly assigned to patients.

CONCLUSIONS

Psychiatric and behavioral side effects occur more frequently in patients taking LEV and ZNS than any other AED and led to higher rates of intolerability. Lower PBSE rates were seen in patients taking CBZ, CLB, GBP, LTG, OXC, PHT, and VPA. Our findings may help facilitate the AED selection process.

Psychiatric side effects and antiepileptic drugs: Observations from prospective audits

Psychiatric comorbidities are common in people with epilepsy. A retrospective study of characteristics associated with withdrawal due to psychiatric side effects was undertaken in patients with treated epilepsy participating in prospective audits with new antiepileptic drugs (AEDs). A total of 1058 treated patients with uncontrolled seizures (942 focal-onset seizures, 116 generalized genetic epilepsies [GGEs]) participated in eight prospective, observational audits from 1996 to 2014. These patients were prescribed adjunctive topiramate (n=170), levetiracetam (n=220), pregabalin (n=135), zonisamide (n=203), lacosamide (n=160), eslicarbazepine acetate (n=52), retigabine (n=64), or perampanel (n=54). Doses were titrated according to efficacy and tolerability to optimize zeizure outcomes and reduce side effects. Psychiatric comorbidities were recorded prior to and after the addition of each AED. At baseline, patients with focal-onset seizures (189 of 942; 20.1%) were statistically more likely to have psychiatric diagnoses compared to patients with GGEs (14 of 116, 12.1%; p=0.039). Following adjunctive AED treatment, neuropsychiatric adverse effects led to AED withdrawal in 1.9-16.7% of patients. Patients with a pre-treatment psychiatric history (22 of 209; 10.5%) were statistically more likely to discontinue their new AED due to psychiatric issues compared to patients with no previous psychiatric diagnosis (50 of 849; 5.9%; p=0.017). Patients receiving sodium channel blocking AEDs (4 of 212, 1.9%) were statistically less likely to develop intolerable psychiatric problems, compared to those on AEDs possessing other mechanisms of action (68 of 846, 8.0%; p=0.012). Depression was the commonest problem, leading to discontinuation of AEDs in 2.8% (n=30) patients. Aggression was statistically more common in men (11 of 527, 2.1%) compared to women (1 of 531, 0.2%; p=0.004). Patients with learning disability (12 of 122, 9.8%; p=0.0015) were statistically less likely to have psychiatric issues prior to adjunctive AED treatment compared to other patients (208 of 936, 22.2%), but there were no statistically significant differences once the new AEDs were added (8 of 122 patients with learning disability, 6.6%; 64 of 936 other patients, 6.8%). Awareness of these issues may assist clinicians in avoiding, identifying and treating psychiatric comorbidities in people with epilepsy.

Psychiatric and behavioral side effects of anti-epileptic drugs in adolescents and children with epilepsy

PURPOSE

The objective of the study was to compare the psychiatric and behavioral side effect (PBSE) profiles of both older and newer antiepileptic drugs (AEDs) in children and adolescent patients with epilepsy.

METHOD

We used logistic regression analysis to test the correlation between 83 non-AED/patient related potential predictor variables and the rate of PBSE. We then compared for each AED the rate of PBSEs and the rate of PBSEs that led to intolerability (IPBSE) while controlling for non-AED predictors of PBSEs.

RESULTS

922 patients (≤18 years old) were included in our study. PBSEs and IPBSEs occurred in 13.8% and 11.2% of patients, respectively. Overall, a history of psychiatric condition, absence seizures, intractable epilepsy, and frontal lobe epilepsy were significantly associated with increased PBSE rates. Levetiracetam (LEV) had the greatest PBSE rate (16.2%). This was significantly higher compared to other AEDs. LEV was also significantly associated with a high rate of IPBSEs (13.4%) and dose-decrease rates due to IPBSE (6.7%). Zonisamide (ZNS) was associated with significantly higher cessation rate due to IPBSE (9.1%) compared to other AEDs.

CONCLUSION

Patients with a history of psychiatric condition, absence seizures, intractable epilepsy, or frontal lobe epilepsy are more likely to develop PBSE. PBSEs appear to occur more frequently in adolescent and children patients taking LEV compared to other AEDs. LEV-attributed PBSEs are more likely to be associated with intolerability and subsequent decrease in dose. The rate of ZNS-attributed IPBSEs is more likely to be associated with complete cessation of AED.

Epilepsy, Antiepileptic Drugs, and Aggression: An Evidence-Based Review

Antiepileptic drugs (AEDs) have many benefits but also many side effects, including aggression, agitation, and irritability, in some patients with epilepsy. This article offers a comprehensive summary of current understanding of aggressive behaviors in patients with epilepsy, including an evidence-based review of aggression during AED treatment. Aggression is seen in a minority of people with epilepsy. It is rarely seizure related but is interictal, sometimes occurring as part of complex psychiatric and behavioral comorbidities, and it is sometimes associated with AED treatment. We review the common neurotransmitter systems and brain regions implicated in both epilepsy and aggression, including the GABA, glutamate, serotonin, dopamine, and noradrenaline systems and the hippocampus, amygdala, prefrontal cortex, anterior cingulate cortex, and temporal lobes. Few controlled clinical studies have used behavioral measures to specifically examine aggression with AEDs, and most evidence comes from adverse event reporting from clinical and observational studies. A systematic approach was used to identify relevant publications, and we present a comprehensive, evidence-based summary of available data surrounding aggression-related behaviors with each of the currently available AEDs in both adults and in children/adolescents with epilepsy. A psychiatric history and history of a propensity toward aggression/anger should routinely be sought from patients, family members, and carers; its presence does not preclude the use of any specific AEDs, but those most likely to be implicated in these behaviors should be used with caution in such cases.

Safety of Long-term Use of Lamotrigine for the Treatment of Psychiatric Disorders

OBJECTIVES

Lamotrigine (LTG) is a drug commonly used to treat epilepsy and can also be used to manage mood disorders, such as bipolar disorder. One of the most dangerous adverse effects of LTG is skin rash, which can make early cessation necessary. Here, we examine the adverse effects associated with long-term use of LTG for the treatment of mood disorders.

METHODS

Data were obtained from the medical records of 101 psychiatric patients who were prescribed long-term treatment with LTG. Patients were retrospectively divided into those who discontinued treatment within 6 months and those who continued for longer, and the groups were compared for adverse effects. We also compared the incidence of adverse effects in high and low doses.

RESULTS

Fifty-four patients continued LTG treatment for 6 months or longer; 47 discontinued within 6 months. A history of allergy was more prevalent among the patients who discontinued treatment early than in those who continued. Of the patients who continued treatment for 6 months or longer, only 2 later discontinued treatment because of adverse effects. Lamotrigine monotherapy showed no difference in the incidence of adverse effects for different doses of LTG (>200 mg = 4.8% vs >100 mg, ≤200 mg = 7.7%; P = 1, vs >50 mg, ≤100 mg = 0%; P = 1 vs ≤50 mg = 0%; P = 1).

CONCLUSIONS

Clinicians must be mindful of the adverse effects occurring early during the titration phase. However, long-term use of LTG was very well tolerated, even at high maintenance doses.

Monotherapy with Levetiracetam Versus Older AEDs: A Randomized Comparative Trial of Effects on Bone Health

Long-term anti-epileptic drug (AED) therapy is associated with increased fracture risk. This study tested whether substituting the newer AED levetiracetam has less adverse effects on bone than older AEDs. An open-label randomized comparative trial. Participants had "failed" initial monotherapy for partial epilepsy and were randomized to substitution monotherapy with levetiracetam or an older AED (carbamazepine or valproate sodium). Bone health assessments, performed at 3 and 15 months, included areal bone mineral density (aBMD) and content at lumbar spine (LS), total hip (TH), forearm (FA), and femoral neck (FN), radial and tibial peripheral quantitative computed tomography and serum bone turnover markers. Main outcomes were changes by treatment group in aBMD at LS, TH, and FA, radial and tibial trabecular BMD and cortical thickness. 70/84 patients completed assessments (40 in levetiracetam- and 30 in older AED group). Within-group analyses showed decreases in both groups in LS (-9.0 %; p < 0.001 in levetiracetam vs. -9.8 %; p < 0.001 in older AED group), FA (-1.46 %; p < 0.001 vs. -0.96 %; p < 0.001, respectively) and radial trabecular BMD (-1.46 %; p = 0.048 and -2.31 %; p = 0.013, respectively). C-terminal telopeptides of type I collagen (βCTX; bone resorption marker) decreased in both groups (-16.1 %; p = 0.021 vs. -15.2 %; p = 0.028, respectively) whereas procollagen Ι N-terminal peptide (PΙNP; bone formation marker) decreased in older AED group (-27.3 %; p = 0.008). The treatment groups did not differ in any of these measures. In conclusion, use of both levetiracetam and older AEDs was associated with bone loss over 1 year at clinically relevant fracture sites and a reduction in bone turnover.

The New Antiepileptic Drugs: Their Neuropharmacology and Clinical Indications

The administration of antiepileptic drugs (AEDs) is the first treatment of epilepsy, one of the most common neurological diseases. Therapeutic guidelines include newer AEDs as front-line drugs; monotherapy with new AEDs is delivered in Japan. While about 70% of patients obtain good seizure control by taking one to three AEDs, about 60% experience adverse effects and 33% have to change drugs. Compared to traditional AEDs, the prolonged administration of new AEDs elicits fewer adverse effects and fewer drug interactions and their teratogenicity may be lower. These characteristics increase drug compliance and allow combination therapy for drug-resistant epilepsy, although the antiepileptic effects of the new AEDs are not greater than of traditional AEDs. Comorbidities are not rare in epileptics; many adult patients present with stroke and brain tumors. In stroke patients requiring risk control and in chemotherapy-treated brain tumor patients, their fewer drug interactions render the new AEDs advantageous. Also, new AEDs offer favorable side benefits for concurrent diseases and conditions. Patients with stroke and traumatic brain injury often present with psychiatric/behavioral symptoms and cognitive impairment and some new AEDs alleviate such symptoms. This review presents an outline of the new AEDs used to treat adult patients based on the pharmacological activity of the drugs and discusses possible clinical indications from the perspective of underlying causative diseases and comorbidities.

Chaihushugan decoction exerts antiepileptic effects by increasing hippocampal glutamate metabolism in pentylenetetrazole-kindled rats

OBJECTIVE

To investigate the antiepileptic effects of Chaihushugan decoction (CHSGD) in rats with pentylenetetrazole (PTZ)-induced seizures and to discuss the impact of CHSGD on glutamate metabolism, a hypothesized underlying mechanism of seizure reduction.

METHODS

Fifty Wistar rats were divided randomly into either control (n = 10) or experimental (n = 40) groups. Rats in the control group were administered physiological saline intraperitoneally. A subconvulsive dose of PTZ (35 mg/kg) was administered intraperitoneally to rats in the experimental group to induce seizures. The fully PTZ-kindled rats were then randomly divided into five subgroups (n = 8 each) based on the following treatment categories: physiological saline, VPA (200 mg/kg), CHSGD (2.5 g/kg), CHSGD (5 g/kg), or CHSGD (10 g/kg), administered orally once per day, respectively. On day 28 following initiation of drug treatment, seizures were monitored. The rats were then sacrificed, and hippocampal dissections were performed for subsequent studies.

RESULTS

CHSGD significantly prolonged the latency of myoclonic, clonic, and tonic seizures, while decreasing overall seizure rates in the kindled rats. The measured concentrations of 2-[N-(7-nitrobenz-2-oxa-1,3-diazo-4-yl) amino]-2-deoxy-d-glucose (2-NBDG) and glutamate were significantly lower in the hippocampi of kindled rats in groups treated with CHSGD compared with those treated with PTZ alone. In addition, CHSGD was found to up-regulate both the expression of glutamate transporter-1 (GLT-1) protein and the activity of glutamine synthetase (GS) in the hippocampi of kindled rats.

CONCLUSION

These results suggest that CHSGD has antiepileptic effects on PTZ-induced seizures. The results further suggest an increase in glutamate metabolism at the synaptic cleft is a putative underlying mechanism of seizure reduction.

Prevalence of depression and anxiety among patients with epilepsy attending the epilepsy clinic at Sheikh Khalifa Medical City, UAE: A cross-sectional study

Depression and anxiety are highly prevalent in patients with epilepsy (PWE), with prevalence rates ranging from 20% to 55%. Unfortunately, the rates, patterns, and risk factors have not been well studied in the Middle East and, to our knowledge, have not been studied at all in the UAE. We screened 186 patients attending an epilepsy clinic using standardized screening tools to determine the rates of both depression and anxiety and compared these rates with that of age- and sex-matched controls. Almost one-third of our patients scored in the depression and anxiety ranges, which was significantly higher compared with the age- and sex-matched controls. Using a multiregression model, none of the studied variables were associated with an increased risk of having either disorder. Depression or anxiety symptoms independently and significantly increased the risk of association with the other disorder. Almost two-thirds of patients with depression and anxiety were not prescribed antidepressant or antianxiety medications.

Forecasting Seizures Using Intracranial EEG Measures and SVM in Naturally Occurring Canine Epilepsy

Management of drug resistant focal epilepsy would be greatly assisted by a reliable warning system capable of alerting patients prior to seizures to allow the patient to adjust activities or medication. Such a system requires successful identification of a preictal, or seizure-prone state. Identification of preictal states in continuous long- duration intracranial electroencephalographic (iEEG) recordings of dogs with naturally occurring epilepsy was investigated using a support vector machine (SVM) algorithm. The dogs studied were implanted with a 16-channel ambulatory iEEG recording device with average channel reference for a mean (st. dev.) of 380.4 (+87.5) days producing 220.2 (+104.1) days of intracranial EEG recorded at 400 Hz for analysis. The iEEG records had 51.6 (+52.8) seizures identified, of which 35.8 (+30.4) seizures were preceded by more than 4 hours of seizure-free data. Recorded iEEG data were stratified into 11 contiguous, non-overlapping frequency bands and binned into one-minute synchrony features for analysis. Performance of the SVM classifier was assessed using a 5-fold cross validation approach, where preictal training data were taken from 90 minute windows with a 5 minute pre-seizure offset. Analysis of the optimal preictal training time was performed by repeating the cross validation over a range of preictal windows and comparing results. We show that the optimization of feature selection varies for each subject, i.e. algorithms are subject specific, but achieve prediction performance significantly better than a time-matched Poisson random predictor (p<0.05) in 5/5 dogs analyzed.

A prospective study of adverse drug reactions to antiepileptic drugs in children

OBJECTIVES

To prospectively determine the nature and rate of adverse drug reactions (ADRs) in children on antiepileptic drugs (AEDs) and to prospectively evaluate the effect of AEDs on behaviour.

SETTING

A single centre prospective observational study.

PARTICIPANTS

Children (<18 years old) receiving one or more AEDs for epilepsy, at each clinically determined follow-up visit.

PRIMARY AND SECONDARY OUTCOMES

Primary outcome was adverse reactions of AEDs. Behavioural and cognitive functions were secondary outcomes.

RESULTS

180 children were recruited. Sodium valproate and carbamazepine were the most frequently used AEDs. A total of 114 ADRs were recorded in 56 of these children (31%). 135 children (75%) were on monotherapy. 27 of the 45 children (60%) on polytherapy had ADRs; while 29 (21%) of those on monotherapy had ADRs. The risk of ADRs was significantly lower in patients receiving monotherapy than polytherapy (RR: 0.61, 95% CI 0.47 to 0.79, p<0.0001). Behavioural problems and somnolence were the most common ADRs. 23 children had to discontinue their AED due to an ADR.

CONCLUSIONS

Behavioural problems and somnolence were the most common ADRs. Polytherapy significantly increases the likelihood of ADRs in children.

TRAIL REGISTRATION NUMBER

EudraCT (2007-000565-37).

Ficus religiosa L. figs--a potential herbal adjuvant to phenytoin for improved management of epilepsy and associated behavioral comorbidities

Oxidative stress, together with mitochondrial dysfunction, has been reported to be involved in the pathogenesis of epileptogenesis and its associated comorbidities. Phytoflavonoids have shown numerous beneficial ameliorative effects on different neurological disorders by virtue of their antioxidant effect. The present study investigated the effect of flavonoid-rich ethyl acetate fraction of the crude fig extract of Ficus religiosa in combination with phenytoin on seizure severity, depressive behavior, and cognitive deficit in pentylenetetrazol (PTZ)-kindled mice. The flavonoid-rich ethyl acetate fraction of the crude fig extract was found to show significant antioxidant potential in various in vitro free radical scavenging assays. Combined treatment of this fraction (2.5, 5, and 10 mg/kg; i.p.) along with a subeffective dose of phenytoin (15 mg/kg; i.p.) in postkindled animals once daily for fifteen days showed a dose-dependent decrease in the seizure severity score, a decreased number of mistakes, increased step-down latency in passive shock avoidance paradigm, and decreased immobility time in the tail suspension test in comparison with the phenytoin only-treated group. Biochemical investigations of the brain tissue showed amelioration of thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) levels, and reduced catalase and acetylcholinesterase (AChE) activities, thereby indicating suppression of oxidative stress. In conclusion, the results of the present study showed the protective effect of the flavonoid-rich fraction of F. religiosa along with a subeffective dose of phenytoin in PTZ-kindling-associated cognitive deficit and depressive behavior with complete suppression of seizures through reduction of oxidative stress, supporting the the need for clinical evaluation of the supplementation of phytoflavonoids along with antiepileptic drugs (AEDs) for management of epilepsy and its psychiatric and cognitive comorbidities.

Time to focus on brain tumor-related epilepsy trials

Brain tumor-related epilepsy (BTRE) is a common complication of cerebral glioma. It has a serious impact on the patient's confidence and quality of life and can be life threatening. There are significant differences in the management of BTRE and nontumoral epilepsy in adults. Surgery is performed early in management, and resection can be curative. Radiotherapy can also improve seizure frequency. Antiepileptic drugs (AEDs) are started after first seizure but are only effective at stopping attacks in 50% of cases. There are no satisfactory randomized controlled clinical trials, or even good prospective series, to support using one AED over another with respect to efficacy. Guidelines are therefore based on poor levels of evidence. In general, the choice of AED may depend on risk of early side effect (rash, biochemical, or hematological effects) and whether drug interactions with chemotherapy are likely. In patients with suspected low-grade glioma, where use of chemotherapy early in the management is not standard practice and survival in measured in many years, the drug interactions are less relevant, and rational seizure management should focus on drugs with the fewest long-term effects on neurocognition, personality, mood, and fatigue. While intriguing and potentially very important, there is no good evidence that any specific AED has a clinical antitumor effect or improves survival. Development of special interest groups in BTRE within countries, or between countries, may be a model for promoting better BTRE trials in the future.

Risk factors for psychological distress in community-treated epilepsy

The study aimed to determine risk factors for psychological distress in a community-treated sample of patients with epilepsy. This study investigated the Tasmanian Epilepsy Register participants. Participants included were as follows: aged 13 years and over, able to complete the individual computer-assisted participant interview, and diagnosed with epilepsy following an epilepsy specialist review of the diagnostic epilepsy interview, which was interpreted using standardized diagnostic guidelines. Psychological distress was assessed with the Kessler-10 questionnaire. Risk factors were grouped into four domains: sociodemographic factors, disease-related factors, psychological factors, and treatment-related factors. High or very high levels of psychological distress were reported by 22% of the participants, with 7.8% having very high distress. The regression model showed that psychological distress was significantly associated with female gender (F=18.1, p<0.001), diabetes mellitus (F=8.7, p=0.003), intellectual disability (F=7.1, p=0.06), and not receiving phenytoin (F=5.1, p=0.02). While the model was significant (F=5.78, p<0.001), only 11% of the variance of the K-10 score was explained by these factors (adjusted R-squared=0.11). This study identifies female gender and comorbid medical conditions as risk factors for psychological distress and the use of phenytoin as a protective factor. The few factors identified and the limited variance explained suggest that a focus on epilepsy-related variables is unlikely to explain key influences underlying psychiatric comorbidity in patients with epilepsy.

Homicide during postictal psychosis

Postictal psychosis is characterized by a fluctuating combination of thought disorder, auditory and visual hallucinations, delusions, paranoia, affective change, and aggression including violent behavior. We present a case of homicide following a cluster of seizures. The patient's history and postictal behavior were his consistent with postictal psychosis. Contributing factors resulting in homicide may have included increased seizure frequency associated with a change in his AED regimen seizure frequency. The AED change to levetiracetam may also have increased impulsiveness with diminished mood regulation following discontinuation of carbamazepine. There is evidence that he had a cluster of seizures immediately prior to the murder which may have resulted in the postictal disinhibition of frontal lobe inhibitory systems. This homicide and other violent behaviors associated with postictal psychosis may be avoided with earlier recognition and treatment.

Psychiatric adverse effects of zonisamide in patients with epilepsy and mental disorder comorbidities

Over the last few years, zonisamide has been proposed as a potentially useful medication for patients with focal seizures, with or without secondary generalization. Since psychiatric adverse effects, including mania, psychosis, and suicidal ideation, have been associated with its use, it was suggested that the presence of antecedent psychiatric disorders is an important factor associated with the discontinuation of zonisamide therapy in patients with epilepsy. We, therefore, set out to assess the tolerability profile of zonisamide in a retrospective chart review of 23 patients with epilepsy and comorbid mental disorders, recruited from two specialist pediatric (n=11) and adult (n=12) neuropsychiatry clinics. All patients had a clinical diagnosis of treatment-refractory epilepsy after extensive neurophysiological and neuroimaging investigations. The vast majority of patients (n=22/23, 95.7%) had tried previous antiepileptic medications, and most adult patients (n=9/11, 81.8%) were on concomitant medication for epilepsy. In the majority of cases, the psychiatric adverse effects of zonisamide were not severe. Four patients (17.4%) discontinued zonisamide because of lack of efficacy, whereas only one patient (4.3%) discontinued it because of the severity of psychiatric adverse effects (major depressive disorder). The low discontinuation rate of zonisamide in a selected population of patients with epilepsy and neuropsychiatric comorbidity suggests that this medication is safe and reasonably well-tolerated for use in patients with treatment-refractory epilepsy. Given the limitations of the present study, including the relatively small sample size, further research is warranted to confirm this finding.

Neurobehavioral effects of levetiracetam in brain tumor related epilepsy

The neurobehavioral profile of anti-epileptic drugs (AEDs) has been a recurrent research topic in the scientific literature. As pharmacological treatments for epilepsy continue to evolve, there is a general consensus that newer AEDs have less detrimental side effects in comparison to their older counterparts. Among newer AEDs and epilepsy patients, potential risk for neurobehavioral changes has been reported with levetiracetam (LEV). Conversely, limited data exists regarding the manifestation of this symptomatology in a subgroup of epilepsy patients with brain tumors. The current paper reviews the literature regarding the neurobehavioral profile of LEV in brain tumor related epilepsy and suggestions for future research will be discussed.

[Epilepsy-related psychoses]

BACKGROUND

Epilepsy-related psychoses lie in the border zone between neurology and psychiatry. The aim of this article is to give a brief overview of current knowledge of these psychoses, and to offer recommendations for their treatment.

METHOD

The article is based on a discretionary selection of articles found through a search in PubMed, as well as the authors' own experience with this patient group.

RESULTS

Epilepsy-related psychoses may occur during, after or between seizures. In addition, psychoses may occur as a side-effect of antiepileptic drugs, and as so-called alternative psychosis. The latter may arise in patients who, with the aid of treatment (medication or surgery), have become completely seizure-free. Ictal psychoses and the majority of postictal psychoses are often of such short duration that treatment with antipsychotics is not appropriate. In these cases, optimizing antiepileptic treatment is the best prophylaxis. Treatment with antipsychotics may, however, be indicated for interictal psychoses and for some patients with especially long-lasting or recurrent postictal psychoses.

INTERPRETATION

Different types of epilepsy-related psychosis require different types of treatment, and some are treated with antipychotics. In those circumstances, we recommend the use of medication that is less likely to lower the seizure threshold, for example risperidone.

Hallucinations and comorbid renal tubular acidosis caused by topiramate in a patient with psychiatric history

Few studies have shown that topiramate may induce psychiatric symptoms and metabolic disorders, respectively. Here, we reported a 13-year-old female who presented with topiramate-induced hallucinations and comorbid renal tubular acidosis. She had a history of psychiatric illness and had been taking the medication for 3 months without prior side effects. After the discontinuation of topiramate, she was treated with supplementary potassium and sodium bicarbonate. Subsequently, her psychiatric symptoms and biochemical findings improved. Recognition of drug-induced psychotic symptoms and renal tubular acidosis is important during concomitant topiramate therapy in psychiatric clinic.

Saikosaponin a mediates the anticonvulsant properties in the HNC models of AE and SE by inhibiting NMDA receptor current and persistent sodium current

Epilepsy is one of the most common neurological disorders, yet its treatment remains unsatisfactory. Saikosaponin a (SSa), a triterpene saponin derived from Bupleurum chinensis DC., has been demonstrated to have significant antiepileptic activity in a variety of epilepsy models in vivo. However, the electrophysiological activities and mechanisms of the antiepileptic properties of SSa remain unclear. In this study, whole-cell current-clamp recordings were used to evaluate the anticonvulsant activities of SSa in the hippocampal neuronal culture (HNC) models of acquired epilepsy (AE) and status epilepticus (SE). Whole-cell voltage-clamp recordings were used to evaluate the modulation effects of SSa on NMDA-evoked current and sodium currents in cultured hippocampal neurons. We found that SSa effectively terminated spontaneous recurrent epileptiform discharges (SREDs) in the HNC model of AE and continuous epileptiform high-frequency bursts (SE) in the HNC model of SE, in a concentration-dependent manner with an IC(50) of 0.42 µM and 0.62 µM, respectively. Furthermore, SSa significantly reduced the peak amplitude of NMDA-evoked current and the peak current amplitude of I(NaP). These results suggest for the first time that the inhibitions of NMDA receptor current and I(NaP) may be the underlying mechanisms of SSa's anticonvulsant properties, including the suppression of SREDs and SE in the HNC models of AE and SE. In addition, effectively abolishing the refractory SE implies that SSa may be a potential anticonvulsant candidate for the clinical treatment of epilepsy.

Adverse effects of antiepileptic drugs

More than 150 years after bromide was introduced as the first antiepileptic drug, adverse effects remain a leading cause of treatment failure and a major determinant of impaired health-related quality of life in people with epilepsy. Adverse effects can develop acutely or many years after starting treatment and can affect any organ or structure. In the past two decades, many efforts have been made to reduce the burden of antiepileptic drug toxicity. Several methods to screen and quantify adverse effects have been developed. Patient profiles associated with increased risk of specific adverse effects have been uncovered through advances in the areas of epidemiology and pharmacogenomics. Several new-generation antiepileptic drugs with improved tolerability profiles and reduced potential for drug interaction have been added to the therapeutic armamentarium. Overall, these advances have expanded the opportunities to tailor treatment with antiepileptic drugs, to enhance effectiveness and minimise the risk of toxic effects.

Beneficial and adverse psychotropic effects of antiepileptic drugs in patients with epilepsy: a summary of prevalence, underlying mechanisms and data limitations

Antiepileptic drugs (AEDs) can have both beneficial and adverse psychotropic effects. They act on neurotransmitter systems, neuronal ion permeability and other targets, although the exact mechanisms are not generally fully elucidated. A systematic review of the literature reveals evidence for both positive and negative effects on depression, anxiety, aggression, psychosis and sleep in patients with epilepsy. Topiramate, vigabatrin, levetiracetam, tiagabine and zonisamide have been associated primarily with adverse psychotropic effects, whilst gabapentin, pregabalin, lacosamide and lamotrigine, in particular, have demonstrated a more beneficial psychotropic profile, especially with regard to affective symptoms. This review, however, identifies specific methodological issues with studies that have reported on the psychotropic effects of AEDs, suggesting that some of the findings might be inconclusive or unreliable because of confounding factors, particularly the presence of psychiatric history. More rigorous double-blind, randomized, placebo-controlled trials on larger numbers of patients with epilepsy, with clear inclusion/exclusion criteria, that are specifically designed to investigate psychotropic changes are more likely to produce results that inform clinical practice and direct future research.

Impact of antiepileptic drugs on genesis of psychosis

Opinions regarding the impact of antiepileptic drugs (AEDs) on the genesis of psychotic symptoms are varied. To re-examine this issue, the records of adult patients with partial epilepsy and newly added AEDs were retrospectively surveyed. The types of newly added AEDs and clinical characteristics were compared between 38 patients with active psychosis and 212 without psychotic history during a follow-up period of 3 to 6 months after initiation of AED administration. Using multivariate logistic regression analysis, the significance of possible predictive variables for development of psychosis was evaluated, which demonstrated that use of zonisamide (ZNS) and phenytoin (PHT), presence of complex partial seizures (CPS), and low intelligence level were significantly correlated with psychosis. We concluded that ZNS and PHT are possible risk factors for development of psychosis along with clinical variables, including the presence of CPS and low intelligence level.

Anti-epileptic drugs

Therapeutic Reviews aim to provide essential independent information for health professionals about drugs used in palliative and hospice care. Additional content is available on www.palliativedrugs.com. Country-specific books (Hospice and Palliative Care Formulary USA, and Palliative Care Formulary, British and Canadian editions) are also available and can be ordered from www.palliativedrugs.com. The series editors welcome feedback on the articles (hq@palliativedrugs.com).

Psychiatric symptoms and quality of life in patients with drug-refractory epilepsy receiving adjunctive levetiracetam therapy

Background and Purpose

Levetiracetam (LEV) is a new antiepileptic drug that has been found to be effective as an adjunctive therapy for uncontrolled partial seizures. However, the results of several studies suggested that LEV has negative psychotropic effects, including irritability, aggressiveness, suicidality, and mood disorders. We investigated the impact of adjunctive LEV on psychiatric symptoms and quality of life (QOL) in patients with drug-refractory epilepsy (DRE) and determined the risk factors provoking psychiatric adverse events.

Methods

A 24-week, prospective, open-label study was conducted. At enrollment, we interviewed patients and reviewed their medical charts to collect demographic and clinical information. They were asked to complete self-report health questionnaires designed to measure various psychiatric symptoms and QOL at enrollment and 24 weeks later.

Results

Seventy-one patients were included in the study, 12 patients (16.9%) of whom discontinued LEV therapy due to serious adverse events including suicidality. The risk factor for premature withdrawal was a previous history of psychiatric diseases (odds ratio 4.59; 95% confidence interval, 1.22-17.32). LEV intake resulted in significant improvements in Beck Anxiety Inventory score (p<0.01) and some domains of the Symptom Checklist-90-Revised, such as somatization (p<0.05), obsessive-compulsiveness (p<0.05), depression (p<0.05), and anxiety (p<0.05). These improvements were not related to the occurrence of seizure freedom. The Quality of Life in Epilepsy Inventory-31 overall score and subscale scores, such as seizure worry (p<0.01), overall QOL (p<0.05), emotional well-being (p<0.05), energy-fatigue (p<0.05), and social function (p<0.05), also improved.

Conclusions

Adjunctive LEV in patients with DRE is likely to improve psychiatric symptoms and QOL. Clinicians should be well aware of the psychiatric histories of patients to prevent them from developing serious adverse events related to LEV.

Age-grouped differences in adverse drug events from psychotropic medication

OBJECTIVE

This review aims to detail specific psychotropic medication treatment differences in adverse drug events (ADEs) between children, adolescents, and adults.

METHOD

A thorough data-based search of ADEs was made, augmented by findings from approved and updated U.S. Food and Drug Administration (FDA) drug labels, controlled clinical trial reports, and from FDA information on ADEs at scheduled public hearings.

RESULTS

Children were found to generally exhibit more ADEs to psychotropic medication than adolescents and adults. These ADEs primarily include altered growth velocity, rash, vomiting, dystonia, tics, affect lability, activation, metabolic blood test abnormalities, sedation, sialorrhea, and electrocardiogram irregularities.

CONCLUSION

Children have more biological vulnerabilities than older individuals, which could account for their greater rate of ADEs to psychotropic medication treatment.

Acoustic effects of lamotrigine in pediatric patients with epilepsy

The aim of this study was to investigate the acoustic effects of lamotrigine in pediatric epileptic patients. Newly diagnosed 52 pediatric epileptic patients were assessed standard speech test through a Computerized Speech Lab applied before the beginning of therapy with lamotrigine and 2months after dosage had been stabilized. The voice onset times for /t/, /k(h)/, /p'/ and /t'/ after the therapy and those for /p/, /k/, /p(h)/, /t(h)/ and /k'/ was not affected. Total durations for all stop consonants did not change significantly except that lenis /p/ and /k/ increased significantly (P<0.05). No noteworthy alteration was observed for mean pitch and speaking rate of counting 1-10. Vowel formants and precise articulation rate remained the same. In conclusion, no significant effects of lamotrigine on speech were found in this study. Lamotrigine is safe for acoustic function in pediatric patients.

Efficacy and tolerability of levetiracetam in children with epilepsy

OBJECTIVE

To assess the efficacy and tolerability of levetiracetam (Lev) in children with epilepsy.

METHODS

Open-label observational, prospective, single arm, non-interventional study examining patients (≤14 years) with epilepsy, receiving mono- or combination therapy with levetiracetam. Levetiracetam was started at a dose of approximately 10mg/kg/day. The dose was titrated up with 10mg/kg increments if seizures were poorly controlled but the maximum daily dose could not be more than 60 mg/kg/day. Documented were seizure type and frequency, levetiracetam dose and side effects.

RESULTS

120 patients (39.3% females, mean age 4.5 ± 3.9 years) were enrolled. Average duration of follow-up was 10.3 ± 3.5 months. At study endpoint, 64.8% of patients got seizure free and 83.0% got a seizure reduction of ≥50%. Observed side effects were somnolence, dysphoria, nervousness, dystrophy, somnipathy, asitia, debilitation, etc. and the incidence rate in the study was 47.5%. Four (3.3%) of 120 patients withdrew because of intolerance of side effects. The estimated one year retention rate of levetiracetam was 73.3%. Poor effect was the most common reason for withdrawal.

CONCLUSIONS

In our study, it seemed that levetiracetam was safe and effective for a wide range of epileptic seizures in children with epilepsy.

Zonisamide discontinuation due to psychiatric and cognitive adverse events: a case-control study

OBJECTIVES

Zonisamide (ZNS) is an antiepileptic drug (AED) that has been associated with psychiatric adverse events (PAE) and cognitive adverse events (CAE); controlled studies evaluating these adverse events are limited. Our objectives were to 1) determine the incidence of PAE and CAE leading to the discontinuation of ZNS and 2) identify risk factors for PAE and CAE associated with the discontinuation of ZNS.

METHODS

All patients exposed to ZNS at MINCEP Epilepsy Care between March 2000 and September 2008 were identified. Reasons for discontinuing ZNS were documented. Separate case-control studies were performed to identify risk factors associated with the discontinuation of ZNS due to PAE or CAE via multivariate binary logistic regression.

RESULTS

A total of 544 patients were exposed to ZNS during the study period. PAE and CAE were the most frequently identified reasons for terminating ZNS therapy. The incidence of PAE severe enough to be associated with the discontinuation of ZNS was 6.9%; the incidence of CAE was 5.8%. Factors associated with termination of ZNS therapy due to PAE were past psychiatric history (p = 0.005), symptomatic generalized epilepsy (p = 0.027), and lower maximum ZNS serum concentration (mean = 17.9 mg/L vs 34.7 mg/L, p < 0.001). Independent variables associated with discontinuing ZNS due to CAE were greater number of concomitant AEDs (p = 0.011) and lower maximum ZNS serum concentration (mean = 16.6 mg/L vs 30.6 mg/L, p = 0.002).

CONCLUSIONS

We have identified clinically relevant risk factors associated with the discontinuation of ZNS. Our findings support the concept that selected patients are relatively more vulnerable to CNS adverse events when exposed to ZNS.

Psychiatric disorders in temporal lobe epilepsy: an overview from a tertiary service in Brazil

PURPOSE

To evaluate the frequency and intensity of psychiatric disorders in a group of temporal lobe epilepsy (TLE) patients from a tertiary-care center.

METHODS

Clinical and sociodemographic data of 73 patients were collected and a neuropsychiatric evaluation was performed with the following instruments: Mini-Mental State Examination (MMSE), structured clinical interview (MINI-PLUS), Hamilton Anxiety Scale (HAM-A), Hamilton Depression Scale (HAM-D), Brief Psychiatric Rating Scale (BPRS).

RESULTS

Patients with TLE showed a high frequency of lifetime psychiatric disorders (70%), the most frequent being mood disorders (49.3%). At assessment, 27.4% of the patients were depressed and 9.6% met criteria for bipolar disorder. Nevertheless, depression had not been properly diagnosed nor treated. Anxiety disorders were also frequent (42.5%), mainly generalized anxiety disorder (GAD) (21.9%). Obsessive compulsive disorder (OCD) was present in 11.0% and psychotic disorders in 5.5% of the sample. Patients with left mesial temporal sclerosis (LMTS) exhibited more psychopathologic features, mainly anxiety disorders (p=0.006), and scored higher on HAM-A and HAM-D (p<0.05 in both).

CONCLUSION

TLE is related to a high frequency of psychiatric disorders, such as anxiety and depression, which are usually underdiagnosed and undertreated. Damage to the left mesial temporal lobe, seen in LMTS, seems to be an important pathogenic lesion linked to a broad range of psychopathological features in TLE, mainly anxiety disorders. The present study prompts discussion on the recognition of the common psychiatric disorders in TLE, especially on the Brazilian setting.

Recurrent schizophrenia-like psychosis as first manifestation of epilepsy: a diagnostic challenge in neuropsychiatry

Since the 1950s, several studies have been carried out to investigate the occurrence of schizophrenia-like psychoses in epilepsy. The psychopathological profile comprises symptoms from the affective, schizophrenic, and cognitive domains and the prevalence varies between 2% to 20%. Classification of such conditions is performed according to their temporal relationship with the seizure itself. Although it is well known that epilepsy may be associated with psychotic disorders, it is less widely recognized that relapsing psychotic phenomena may be the first and only symptom of epilepsy. In this research, two patients are described who were initially referred for recurrent episodes of bipolar affective disorder and schizophrenic psychosis, respectively. In both patients, a diagnosis of relapsing postictal psychotic states due to previously undiagnosed epilepsy was made and consequently, treatment with antiepileptics was started. During follow up over several months, they remained free of both epileptic and psychotic symptoms. Given the kaleidoscopic nature of the postictal psychosis and full recovery from this, such psychoses best meet the criteria for a cycloid psychosis. These observations illustrate diagnostic and therapeutic pitfalls due to the conceptual disintegration emerging from the inadequate separation between psychiatry and neurology. Therefore, the importance of a neuropsychiatric viewpoint should be promoted.

Reversible lamotrigine-induced neurobehavioral disturbances in children with epilepsy

A retrospective review was performed in patients who developed neurobehavioral adverse reactions to lamotrigine. Data were obtained from interviews, examinations, and routine medical records. There were 7 male and 2 female patients with epilepsy with a mean age of 5 years. All 9 patients became hyperactive and agitated over a broad range of lamotrigine dosing (0.7-14.0 mg/kg per d). Five patients developed self-injurious and violent behaviors. Two patients developed severe insomnia. The most affected patient was a 6-year-old boy whose mood and affect became extremely volatile. He also experienced threatening visual and auditory hallucinations and insomnia. All 9 patients had dramatic improvement and/or resolution of the adverse neurobehavioral effects following discontinuation or reduction of lamotrigine. Reversible, severe neurobehavioral disturbances associated with lamotrigine therapy have not been reported in the literature. While idiosyncratic and uncommon, this is a potentially significant, clinical side effect. Further studies are necessary to clarify the population at risk.

Levetiracetam extended release and levetiracetam immediate release as adjunctive treatment for partial-onset seizures: an indirect comparison of treatment-emergent adverse events using meta-analytic techniques

The safety profiles of once-daily adjunctive levetiracetam (LEV) extended release (XR) (1000mg/day) and adjunctive LEV immediate release (IR) (500mg twice daily) were compared using data from three randomized, placebo (PBO)-controlled phase III clinical trials in patients with partial-onset seizures. MedDRA 9.0 treatment-emergent adverse events (TEAEs) were indirectly compared using meta-analytic techniques, including calculation of risk difference (RD) and mixed-effects analysis. Statistical significance was set at 10% alpha risk, the normative value for these analyses. Data from 555 patients older than 16 (204 LEV IR, 70 LEV XR, 281 PBO) were analyzed. Following adjustment for incidence of placebo TEAEs, LEV XR showed statistically significantly lower rates of TEAEs than LEV IR across nervous system disorders (RD=-18%, P=0.03), psychiatric disorders (RD=-11%, P=0.08), and metabolism and nutrition disorders (RD=-3%, P=0.08). Among nervous system disorders, the RD for headache favored LEV XR (RD=-11%, P=0.08). These results suggest that adjunctive LEV XR may be associated with a lower incidence of nervous system, psychiatric, and nutritional and metabolic TEAEs as compared with LEV IR. However, this difference was observed at a broad scale and not at a specific TEAE level except for headache.

Epilepsy pharmacogenetics

Large interindividual variation in efficacy and adverse effects of anti-epileptic therapy presents opportunities and challenges in pharmacogenomics. Although the first true association of genetic polymorphism in drug-metabolizing enzymes with anti-epileptic drug dose was reported 10 years ago, most of the findings have had little impact on clinical practice so far. Most studies performed to date examined candidate genes and were focused on candidate gene selection. Genome-wide association and whole-genome sequencing technologies empower hypothesis-free comprehensive screening of genetic variation across the genome and now the main challenge remaining is to select and study clinically relevant phenotypes suitable for genetic studies. Here we review the current state of epilepsy pharmacogenetics focusing on phenotyping questions and discuss what characteristics we need to study to get answers.