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

PurposePsychiatric 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.MethodsAs 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.ResultsPsychiatric 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.ConclusionsPsychiatric 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.     

Cross-reactivity of skin rashes with current antiepileptic drugs in Chinese population

ObjectiveDue to less experience with the cross-reactivity of antiepileptic drugs (AEDs) in Chinese population, we surveyed the rates of cross- reactivity of rash among commonly used AEDs in Chinese patients with epilepsy, particularly between the traditional and the new compounds.MethodsWe have retrospectively reviewed the medical records concerning all antiepileptic drug treatment in consecutive Chinese patients with epilepsy in our center. The incidence of AED-related rash was determined in 3793 outpatients, taking at least one of the AEDs-carbamazepine (CBZ), valproic acid (VPA), phenytoin (PHT), phenobarbital (PB), clonazepam (CZP), oxcarbazepine (OXC), lamotrigine (LTG), gabapentin (GBP), topiramate (TPM), levetiracetam (LEV) and traditional Chinese medicine (TCM). We have performed telephone interviews among all patients with AEDs-related rash. We described the clinical characteristics of the 18 patients with cross-reactivity involving the AEDs, and the cross- reactivity pattern for CBZ, PHT, OXC, and LTG.ResultsA total of 3.61% (137/3793) of patients experienced a skin rash to at least one AEDs, of these patients, 73 (53.28%) were female and 64 were males (46.72%). While 18 patients had a rash to two or more AEDs. Of patients who had a rash to CBZ and were also prescribed PHT (n = 17), 52.9% had a rash to PHT (abbreviated as CBZ → PHT: 52.9%); of patients who had a rash to PHT and were also prescribed CBZ (n = 13), rate of rash was 69.2% (i.e., PHT → CBZ: 69.2%). Other results: CBZ → LTG: 25% (n = 16); LTG  → CBZ: 44.4% (n = 9); CBZ → OXC: 40% (n = 10); OXC → CBZ: 66.7% (n = 6); LTG → PHT: 20% (n = 5); PHT → LTG: 16.7% (n = 6); OXC → LTG: 25% (n = 4); LTG → OXC: 33.3% (n = 3); OXC → PHT: 25% (n = 4); PHT → OXC: 16.7% (n = 6). There was a highly significant mutual risk for cross- reactivity for CBZ and PHT, and OXC, and LTG (p < 0.001), mutual risk reached statistical significance for LTG and CBZ (p = 0.01).ConclusionCross-reactivity rates between certain AEDs are high, especially when involving carbamazepine and phenytoin. There were also too few patients with rash to reach definitely conclusions about possible cross-reactivity. Larger numbers of patients would be needed to assess this and the mechanism. Caution should be exercised when prescribing certain AEDs (especially CBZ and PHT, but also OXC, and LTG).     

Is lamotrigine a significant human teratogen? Observations from the Australian Pregnancy Register

Lamotrigine (LTG) is increasingly being prescribed in pregnancy for women with epilepsy in place of valproate (VPA), because of the teratogenic risks associated with the latter. It is therefore important to know the teratogenic hazard associated with LTG, relative to VPA and to other commonly used antiepileptic drugs (AEDs). Data from the Australian Register of Antiepileptic Drugs in Pregnancy was examined to determine the incidence of teratogenicity determined 1 year from completion of pregnancy in women who took AEDs in monotherapy during pregnancy. Compared with a 3.4% malformation incidence in women who took no AEDs (N = 118), the incidences for LTG (N = 243), carbamazepine (CBZ) (N = 302) and VPA (N = 224) were, respectively, 4.9%, 5.3% and 15.2%, the latter statistically significantly greater than the risk for no AED therapy in pregnant women with epilepsy. Logistic regression analysis showed no tendency for foetal hazard to increase with increasing LTG dose in pregnancy, unlike the situation for VPA. However, seizure control in pregnancy tended to be not as good in the women taking LTG compared with those taking VPA, though the data examined were not adequate to permit definite conclusions regarding this matter. We conclude that LTG monotherapy in pregnancy is safer than valproate monotherapy from the point of view of foetal malformations, and no more hazardous in this regard than therapy with other commonly used AEDs.     

Effectiveness and tolerability of antiepileptic drugs in 104 girls with Rett syndrome

Approximately 60–80% of girls with Rett Syndrome (RTT) have epilepsy, which represents one of the most severe problems clinicians have to deal with, especially when patients are 7–12 years old.The aim of this study was to analyze the antiepileptic drugs (AEDs) prescribed in RTT, and to assess their effectiveness and tolerability in different age groups from early infancy to adulthood.We included in this study 104 girls, aged 2–42 years (mean age 13.9 years): 89 had a mutation in MECP2, 5 in CDKL5, 2 in FOXG1, and the mutational status was unknown in the remaining 8.Epilepsy was present in 82 patients (79%). Mean age at epilepsy onset was 4.1 years.We divided the girls into 5 groups according to age: < 5, 5–9, 10–14, 15–19, 20 years and older.Valproic acid (VPA) was the most prescribed single therapy in young patients (< 15 years), whereas carbamazepine (CBZ) was preferred by clinicians in older patients. The most frequently adopted AED combination in the patients younger than 10 years and older than 15 was VPA and lamotrigine (LTG).Seizures in the group aged 10–14 years were the most difficult to treat, requiring a mean of three different AEDs, often used in combination and mostly including VPA. Seizures in fifteen patients (18%) were considered drug resistant. VPA was reported as the most effective AED in younger girls (in 40% of the patients aged < 5 years, in 19% of the girls aged 5–9 years), and CBZ the most effective in the patients 15 years or older. Adverse reactions did not differ from expected: agitation, drowsiness, and weight loss were the most frequently reported. In our sample, LTG was the least tolerated AED. We did not find correlations with MECP2 mutations in terms of effectiveness or adverse reactions.Conclusion: in this study we observed different effectiveness of AEDs based on age, and suggest that clinicians consider age-dependency when prescribing appropriate AEDs in the RTT population.     

Association between antiepileptic drug dose and long-term response in patients with refractory epilepsy

Seizures in patients with medically refractory epilepsy remain a substantial clinical challenge, not least because of the dearth of evidence-based guidelines as to which antiepileptic drug (AED) regimens are the most effective, and what doses of these drugs to employ. We sought to determine whether there were regions in the dosage range of commonly used AEDs that were associated with superior efficacy in patients with refractory epilepsy. We retrospectively analyzed treatment records from 164 institutionalized, developmentally disabled patients with refractory epilepsy, averaging 17 years of followup per patient. We determined the change in seizure frequency in within-patient comparisons during treatment with the most commonly used combinations of 12 AEDs, and then analyzed the response to treatment by quartile of the dose range for monotherapy with carbamazepine (CBZ), lamotrigine (LTG), valproate (VPA), or phenytoin (PHT), and the combination LTG/VPA. We found that of the 26 most frequently used AED regimens, only LTG/VPA yielded superior efficacy, similar to an earlier study. For the monotherapies, patients who were treated in the lowest quartile of the dose range had significantly better long-term reduction in seizure frequency compared to those treated in the 2nd and 3rd quartiles of the dose range. Patients with paired exposures to CBZ in both the lowest quartile and a higher quartile of dose range experienced an increase in seizure frequency at higher doses, while patients treated with LTG/VPA showed improved response with escalation of LTG dosage. We conclude that in this population of patients with refractory epilepsy, LTG/VPA was the most effective AED combination. The best response to AEDs used in monotherapy was observed at low dosage. This suggests that routine exposure to maximally tolerated AED doses may not be necessary to identify those patients with drug-resistant seizures who will have a beneficial response to therapy. Rather, responders to a given AED regimen may be identified with exposure to low AED doses, with careful evaluation of the response to subsequent titration to identify non-responders or those with exacerbation of seizure frequency at higher doses.     

Population-based study of antiepileptic drug exposure in utero—Influence on head circumference in newborns

PurposeTo study the effect of AED exposure on head circumference in the newborn.MethodsData on all Swedish singletons births between 1995 and 2005, over 900,000 births, were obtained from the Swedish Medical Birth Registry. The effects of AEDs on birth-weight-adjusted mean head circumference (bw-adj-HC) were estimated by comparison with data from all births in an analysis which was adjusted for year of birth, maternal age, parity, maternal smoking, and maternal body mass index.ResultsA significant reduction of mean bw-adj-HC was seen after both carbamazepine (CBZ) (standard deviation scores (SDS) = 0.15, p < 0.001) and valproic acid (VPA) (SDS = 0.10, p = 0.04) in monotherapy. No effect on mean bw-adj-HC was seen for phenytoin, clonazepam, lamotrigine and gabapentin. There was a significant increase in the occurrence of microcephaly (bw-adj-HC smaller than 2 SD below the mean) after any AED polytherapy (OR = 2.85, 95% CI: 1.74–4.78) but not after AED monotherapy or monotherapy with CBZ or VPA. CBZ or VPA was taken by 71% of the pregnant mothers on AED, and the usage increased over time.ConclusionsCBZ and VPA in monotherapy during pregnancy reduce mean bw-adj-HC. AED polytherapy increases the rate of microcephaly but no significant effect is seen of AED monotherapy. The possible significance for the further development of the child is uncertain but should be explored.     

Prospective audits with newer antiepileptic drugs in focal epilepsy: Insights into population responses?

Despite the availability of a wide range of new antiepileptic drugs (AEDs), there is little evidence that their introduction has substantially altered outcomes. This paper reviews data from 5 consecutive prospective audits with new AEDs using similar methodology. Prospective audits with topiramate (TPM; n = 135), levetiracetam (LEV; n = 136), zonisamide (ZNS; n = 141), pregabalin (PGB; n = 135), and lacosamide (LCM; n = 160) were undertaken in treated patients with uncontrolled partial-onset seizures. Follow-up continued until one of four endpoints was reached: seizure freedom for ≥ 6 months on unchanged dosing; ≥ 50% reduction (responder) in seizure frequency on the highest tolerated dose compared with baseline; < 50% seizure frequency reduction (marginal response) compared with baseline in patients wishing to continue treatment with the new AED; or withdrawal due to lack of efficacy, side effects, or both. A greater proportion of seizure-free patients occurred with LEV (23.5%), LCM (21.9%), and TPM (20.7%) than with ZNS (12.8%) and PGB (10.4%). A higher percentage discontinued treatment with ZNS (41.8%) and PGB (50.4%) than with LEV (32.4%), TPM (31.1%), and LCM (22.5%). Most seizure-free patients responded to the new agent as first or second add-on (TPM 96%; LEV 97%; ZNS 89%; PGB 86%; LCM 97%) often at modest or moderate dosing (TPM 68%, ≤ 200 mg/day; LEV 63%, ≤ 1000 mg/day; ZNS 61%, ≤ 100 mg/day; PGB 86%, ≤ 300 mg/day; LCM 74%, ≤ 200 mg/day). With < 10% of patients discontinuing all AEDs due to lack of efficacy, tolerability was the major factor influencing the number of patients remaining on treatment. Lacosamide was the best (77% patients continued treatment), while PGB was the worst (50% continued treatment) tolerated AED. Overall, seizure freedom was achieved in < 25% of patients in each audit, mainly as a first or second add-on, with best tolerated AEDs producing a higher number of good outcomes. Seizures in very few patients with drug-resistant epilepsy, as defined by the International League Against Epilepsy task force, responded to any of the 5 newer AEDs. These data support the suggestion that the introduction of modern agents has not importantly impacted the outcomes in refractory epilepsy.     

Comparison of the effectiveness of four antiepileptic drugs in the treatment of status epilepticus according to four different efficacy criteria

The preliminary data presented here shall give an impression on how different criteria for the identification of an antiepileptic drug (AED) with a possible or certain treatment effect can have an influence on the results of retrospective case series. We present a data subset from a large retrospective study which, when completed, will cover all treatment episodes of status epilepticus (SE) at the neurological department of the Universitätsmedizin Rostock from January 2010 to June 2013. We compare and contrast the results of four different efficacy criteria for the effectiveness of phenytoin (PHT), valproate (VPA), levetiracetam (LEV), and lacosamide (LCM): criterion 1 = the last AED administered before SE termination; criterion 2 = the last drug introduced into the antiepileptic therapy within 72 h before SE termination and without changes in the comedication; criterion 3 = the last drug introduced into the antiepileptic therapy or increased in dose within 24 h before SE termination without changes in the comedication; and criterion 4 = the last drug introduced into the antiepileptic therapy within 72 h before SE termination, even allowing changes in the comedication. Thirty-seven treatment episodes in 32 patients (13 male and 19 female, mean age at first episode: 68 years, SD: 17) could be analyzed. In 31 episodes, at least one AED was given intravenously. Efficacy rates in the whole case series according to all four criteria were not significantly different between the four AEDs, but there was a considerable difference in the efficacy rates of each AED when evaluating them with the different efficacy criteria. Our data show that statistically significant results concerning the efficacy of different AEDs in different subtypes of SE may depend on the outcome criteria. Therefore, efficacy criteria for the effectiveness of AEDs in the treatment of SE should be standardized.This article is part of a Special Issue entitled Status Epilepticus.     

Pharmacodynamic and pharmacokinetic interactions of perampanel and other antiepileptic drugs in a rat amygdala kindling model

PurposeThis study explored the pharmacodynamic and pharmacokinetic effects of combining perampanel (PER) with commonly co-administered AEDs.MethodA strong stimulus intensity (three-fold higher than after-discharge threshold) was used to elicit drug-resistant seizures in a rat amygdala kindling model. Vehicle, low-dose PER (0.75 mg/kg), or high-dose PER (1.5 mg/kg), in combination with vehicle, levetiracetam (LEV) 50 mg/kg, lamotrigine (LAM) 20 mg/kg, carbamazepine (CBZ) 20 mg/kg, or valproic acid (VPA) 200 mg/kg, were administered intraperitoneally to groups of 6–13 rats. Seizure score, electroencephalography (EEG) seizure duration, and motor seizure duration were evaluated, with pharmacodynamic interactions determined by two-way analysis of variance (ANOVA). Motor impairment was evaluated by rotarod test and two-way ANOVA.ResultsHigh-dose PER, but not low-dose PER, LEV, LAM, CBZ, or VPA, reduced EEG seizure duration, motor seizure duration, and seizure score compared with vehicle alone. However, when low-dose PER was administered in combination with LEV, LAM, CBZ, or VPA, seizure severity parameters were reduced compared with the concomitant AEDs alone. These pharmacodynamic interactions were statistically significant in some cases, but the same AED combinations were not associated with statistically significant neurotoxic interactions. Efficacy may have been slightly affected by changes in PER plasma concentrations in the presence of other AEDs:PER plasma concentrations increased with LEV or LAM co-administration, and decreased with CBZ or VPA co-administration.ConclusionOverall, these data support published Phase III data demonstrating the efficacy of PER as adjunctive therapy for the treatment of refractory partial-onset seizures in patients aged ≥12 years.     

Antiepileptic drug prescribing patterns in Iraq and Afghanistan war veterans with epilepsy

ObjectiveWe examined patterns of antiepileptic drug (AED) use in a cohort of Iraq/Afghanistan war veterans (IAVs) who were previously identified as having epilepsy. We hypothesized that clinicians would be more likely to prescribe newer AEDs and would select specific AEDs to treat seizures based on patient characteristics including gender and comorbidities.MethodsFrom the cohort of IAVs previously identified with epilepsy between fiscal years 2009 and 2010, we selected those who received AEDs from the Veterans Health Administration in FY2010. Regimens were classified as monotherapy or polytherapy, and specific AED use was examine overall and by gender. Multivariable logistic regression examined associations of age; gender; race/ethnicity; medical, psychiatric, and neurological comorbidities; and receipt of neurology specialty care associated with the six most commonly used AEDs.ResultsAmong 256,284 IAVs, 2123 met inclusion criteria (mean age: 33 years; 89% men). Seventy-two percent (n = 1526) received monotherapy, most commonly valproate (N = 425) and levetiracetam (n = 347). Sixty-one percent of those on monotherapy received a newer AED (levetiracetam, topiramate, lamotrigine, zonisamide, oxcarbazepine). Although fewer women than men received valproate, nearly 90% (N = 45) were of reproductive age (≤ 45 years). Antiepileptic drug prescribing patterns were associated with posttraumatic stress disorder, bipolar disorder, cerebrovascular disease, dementia/cognitive impairment, headache, and receipt of neurological specialty care (all p < 0.01).SignificanceIn this cohort of veterans with epilepsy, most received AED monotherapy and newer AEDs. Prescribing patterns were different for men and women. The patterns observed between AEDs and neurological/psychiatric comorbidities suggest that clinicians are practicing rational prescribing.     

What do epileptologists recommend about discontinuing antiepileptic drugs for a second time in children?

ObjectiveThere is a broad consensus that antiepileptic drugs (AEDs) may be withdrawn after two years of seizure freedom for most children with epilepsy. If seizures recur and are, again, completely controlled with AEDs, little is known about discontinuing a second time. We surveyed American and Canadian pediatric epileptologists to understand their current practice.MethodsIn 2014, a survey was sent via e-mail to 193 pediatric epileptologists to learn about AED discontinuation practices in children. The survey asked direct questions about practice and posed five “real-life” cases where the decision to discontinue might be difficult. Participants were identified through membership lists of several US and Canadian epilepsy organizations.ResultsThere were 94 (49%) completed surveys. Sixty-three participants had ≥ 10 years in practice (“more experienced”: mean 23 ± 9 years), and 31 had < 10 years (“less experienced”: mean 6 ± 2). Overall, 62% recommended AED discontinuation for the first time after 2–3 years of seizure freedom, and 61% recommended discontinuation for the second time after 2–3 years. Fifty-six percent of “more experienced” clinicians required a longer seizure-free period prior to a second discontinuation (p < 0.001) compared with 26% of “less experienced” clinicians (p = ns). Overall, most participants suggested an AED taper duration of 2–6 months for the first and second attempts, 52% and 68%, respectively. Both groups wean AEDs more slowly during the second attempt (p < 0.001). There was only 40–60% agreement among participants to discontinue AEDs in four of the cases.ConclusionNearly half (46%) of pediatric epileptologists require a longer seizure-free period the second time they attempt to discontinue AEDs compared with the first attempt and wean down AEDs somewhat more slowly. Although a variety of factors influence decision-making, there was a high level of disagreement to discontinue AEDs a second time in “real-life” cases.     

Measurement of levetiracetam drug levels to assist with seizure control and monitoring of drug interactions with other anti-epileptic medications (AEMs)

PurposeLevetiracetam (LEV) therapeutic range (20–40 mg/L) and potential drug interactions were assessed in people with epilepsy (PWE).MethodFifty-two PWE had LEV and concomitant medications [carbamazepine (CBZ); valproate (VPA); lamotrigine (LTG)] blood levels measured and compared to seizure activity. Lacosamide (LCM) levels were unavailable. Adopted therapeutic ranges were: 20–40 mg/L – LEV; 25–50 μmol/L – total CBZ; 6–13 μmol/L – free CBZ; 300–750 μmol/L – total VPA; 30–75 μmol/L – free VPA; and 40–60 μmol/L – LTG. Seizure-freedom was assessed and patients followed for almost two years.Results23 of 52 PWE (44%) used LEV monotherapy and 16/23 (70%) had ‘therapeutic’ LEV with 13/16 (81%) seizure-free. 29 of 52 (56%) used polytherapy and 16/29 (55%) had ‘therapeutic’ LEV with 7/16 (44%) seizure-free. 11 of 29 (38%) used CBZ: 4/11 (36%) had therapeutic mean LEV levels and 7/11 (64%) were seizure-free. Fourteen (48%) used VPA: 9/14 (64%) had therapeutic mean LEV levels and 8/14 (57%) were seizure-free. 13 of 29 (45%) used LTG: 8/13 (62%) had therapeutic mean LEV levels and 5/13 (38%) were seizure-free. LEV did not alter CBZ, but CBZ affected LEV. LEV elevated VPA free levels but not VPA total levels. Dosage/concentration was lowered with polytherapy.ConclusionLEV range (20–40 mg/L) assisted epilepsy management and anti-epileptic medication interactions were suggested with polytherapy thus possibly explaining the impaired efficacy of LEV with polytherapy.     

Seizure outcome after AED failure in pediatric focal epilepsy: Impact of underlying etiology

ObjectiveThis study aimed to identify long-term seizure outcome in pediatric nonsyndromic focal epilepsy after failure of serial antiepileptic drugs (AEDs) due to lack of efficacy.MethodsChildren (1 month–17 years) with new-onset focal epilepsy not meeting the criteria for a defined electroclinical syndrome diagnosed between 1980 and 2009 while residing in Olmsted County, MN, were retrospectively identified. Medical records of those followed for ≥ 2 years were reviewed to assess etiology, the number of AEDs that failed due to lack of efficacy, and seizure outcome at final follow-up. Etiology was classified into structural/metabolic, genetic, or unknown. Favorable outcome was defined as seizure freedom ≥ 1 year, on or off AEDs, without prior epilepsy surgery. Poor outcome was defined as ongoing seizures in the preceding year or having undergone prior epilepsy surgery.ResultsNonsyndromic focal epilepsy accounted for 275/468 (59%) of all patients with newly diagnosed epilepsy — of these, 256 (93%) were followed for a minimum of two years and were included in the study. Median duration of follow-up was 10.0 years. At least one AED had failed due to lack of efficacy in 100 (39.1%) children. Favorable outcomes occurred in 149/156 (95.5%) children with no AED failure, 16/30 (53.3%) with one AED failure, 8/25 (32%) with two AED failures, and only 2/45 (4.4%) with three AED failures. After two AED failures, the seizures of nearly one-quarter of children who had epilepsy with an unknown cause responded favorably to the third AED compared with only 7.8% of the cohort that had epilepsy with a structural/metabolic cause. Children with a remote brain insult had a significantly higher likelihood of favorable outcome with serial AEDs than those with other structural abnormalities.SignificanceEtiology is an important determinant of pharmacoresistance in nonsyndromic focal epilepsy. Surgical evaluation should be considered after failure of 1–2 AEDs in those who have epilepsy with structural causes, excluding remote brain insults. Conversely, as surgical success is lower with normal MRI or more diffuse brain insults, it appears reasonable to hold off surgical evaluation until 2–3 AEDs have failed in such children.     

Differential effects of antiepileptic drugs on neonatal outcomes

Offspring of women with epilepsy (WWE) on AEDs are at increased risks for major congenital malformations and reduced cognition. They may be at risk for other adverse neonatal outcomes. Women with epilepsy on carbamazepine (CBZ), lamotrigine (LTG), phenytoin (PHT), or valproate (VPA) monotherapy were enrolled in a prospective, observational, multicenter study of the neurodevelopmental effects of AEDs. The odds ratio for small for gestational age (SGA) was higher for VPA vs. PHT, VPA vs. LTG, and CBZ vs. PHT. Microcephaly rates were elevated to 12% for all newborns and at 12 months old, but normalized by age 24 months. Reduced Apgar scores occurred more frequently in the VPA and PHT groups at 1 min, but scores were near normal in all groups at 5 min. This study demonstrates increased risks for being born SGA in the VPA and CBZ groups, and transiently reduced Apgar scores in the VPA and PHT groups. Differential risks among the AEDs can help inform decisions about AED selection for women during childbearing years.     

Efficacy,tolerability, and retention rates of zonisamide in older adult patients with focal-onset epilepsy: Experiences from two tertiary epilepsy centers

ObjectiveThe objective of this study was to evaluate the efficacy, tolerability, and retention rates for zonisamide (ZNS) in older adult patients with focal-onset epilepsy.Patients and methodsChart reviews of patients aged 60 years and older with focal-onset epilepsy treated with ZNS in two tertiary epilepsy centers were analyzed retrospectively.ResultsEighty-five patients (41 males, 44 females) aged over 60 years (range: 60–81) with focal-onset epilepsy treated with ZNS were identified; 55.3% of the patients (n = 47) were on monotherapy. The median and average doses of ZNS doses were 200 mg/day (range: 100–400) and 212.9 ± 84.2 mg/day, respectively. With ZNS treatment, 67.1% of the patients (n = 57) were seizure-free for a median of 28 months (range: 10–56) whereas 20% (n = 17) of the patients had seizures that were unresponsive to ZNS treatment. Best seizure control was achieved in patients with poststroke epilepsy; seizure freedom was 80% in this subgroup.Overall retention rate was found to be 83.5%. There was no significant relation between receiving poly- or monotherapy and discontinuation of ZNS (p = 0.18).Thirty-two of the patients (37.6%) lost weight. Median weight loss was 8 kg (range: 2–16). There was no significant correlation between weight loss and the administered doses of ZNS (r = 0.34; p = 0.12).ConclusionDespite limitations due to the retrospective design of the study, the results show that ZNS is a well-retained drug with high efficacy in older adult patients with epilepsy.     

Assessment of atherosclerosis risk due to the homocysteine–asymmetric dimethylarginine–nitric oxide cascade in children taking antiepileptic drugs

PurposeThe aim of this study was to assess the atherogenicity risk of antiepileptics in children by investigating the cascade, “hyperhomocysteinemia (HHcy) → asymmetric dimethylarginine (ADMA) increase → nitric oxide (NO) decrease”, which is thought to contribute to the developmental process of atherosclerosis.MethodsThe participants included 53 epilepsy patients who received either valproic acid (VPA, n = 26) or oxcarbazepine (OXC, n = 27). Twenty-four healthy sex- and age-matched children served as controls. Fasting plasma total homocysteine (tHcy), ADMA and NO levels were measured.ResultsThe differences in Hcy, ADMA, NO, vitamin B₁₂ and folate levels between VPA, OXC and control groups were all insignificant (p > 0.05 for all). In the patient group (VPA and OXC groups), 22.6% of the children (12/53) had tHcy levels above the normal cutoff (13.1 μmol/l) for children and 17% of the children (9/53) had tHcy levels of greater than 15 μmol/l which is accepted as the critical value for an increased atherosclerosis risk (p < 0.05 for both). The difference in rate of HHcy between VPA and OXC groups was statistically insignificant (p > 0.05, for both cut off levels of HHCy). There was a positive correlation of tHcy levels and antiepileptic drug treatment duration in the patient group (r = +0.276, p < 0.05).ConclusionHHcy may develop in patients using OXC. Contrary to some previous publications, our data do not suggest that OXC is safer than VPA in terms of HHcy risk. Further prospective, large scale and longer term studies investigating all suggested pathways responsible for development of atherosclerosis due to HHcy should be conducted to define the exact mechanism responsible for AEDs related atherosclerosis.     

Cognitive functions in children exposed to antiepileptic drugs in utero - Study in Georgia

ObjectiveThe cognitive teratogenicity of antiepileptic drugs (AEDs) has gained increasing attention in the last decade. The objective of the current study was to assess the effects of AED fetal exposure on the cognitive development of children of mothers with epilepsy from Georgia in a controlled study taking into consideration major confounding factors.MethodsA prospective cohort group was formed from children and mothers registered in the Georgian National AED-Pregnancy Registry. The study group's age- and gender-matched control children without fetal AED exposure were selected retrospectively. The Intelligence Quotient (IQ) using the Wechsler Adult Intelligence Scale – revised (WAIS-R) was assessed in mothers. The Wechsler Preschool and Primary Scale of Intelligence (WPPSI-4) were used to assess intellectual functioning for children of both study and control groups. Linear regression analysis was performed to detect association of AED exposure on the cognitive performance of children.ResultsIn total, 100 children aged 36 to 72 months were evaluated. The IQ of WWE was significantly lower compared to women without epilepsy in all modalities. Exposure to valproate (VPA) (n = 18) was associated with lowest cognitive performance regarding Full Scale IQ (FSIQ) (β, − 12.04; p = 0.006) and verbal comprehension (VCI) (β, − 8.89; p = 0.019). Maternal FSIQ, maternal performance IQ (PIQ), and child's age at first phrases were independent factors associated with the cognitive development of children.ConclusionsMultivariate analysis showed VPA to be an independent predictor for decreased cognitive performance. Maternal FSIQ, PIQ, and child developmental achievements were significant confounders for cognitive performance in children.     

Risk factors for valproic acid resistance in childhood absence epilepsy

AimsValproic acid (VPA) is reported to be effective for the control of absence seizures in 75% of children. The aim of this study was to determine the clinical and socio-demographic factors associated with VPA response in newly diagnosed childhood absence epilepsy (CAE) and to determine if these factors also influence the chances of achieving long-term seizure freedom.MethodsMedical charts of 180 children with CAE were retrospectively reviewed. Clinical, electroencephalographic and imaging findings were recorded to correlate with complete VPA response and long-term epilepsy outcome. Factors associated with non-responsiveness were identified individually and in a multivariable logistic regression analysis.ResultsTreatment was successful in 112 (58.3%) children. More children that were non-responsive to VPA experienced generalized tonic clonic seizures (GTCS) (33.8% vs. 13.4% for responders; p = 0.001) and 52.9% had a pre-treatment seizure frequency greater than 10/day (vs. 27.0% for responders; p < 0.001). Finally, responders were older at time of diagnosis versus non-responders (p = 0.001). Absence of long-term seizure freedom was linked to the presence of GTCS, the absence of initial response and the need for multiple AEDs to control seizures.InterpretationOur results suggest that clinical phenotypes are associated with reduced response rates to VPA. This should be taken into account when counselling families of children with newly diagnosed absence epilepsy.     

Health-care costs and utilization related to long- or short-acting antiepileptic monotherapy use

PurposeThis study aimed to compare health-care utilization and costs in patients treated with long-acting (LA) vs. short-acting (SA) antiepileptic drug (AED) monotherapy.MethodsWe conducted a cross-sectional study of claims from the OptumInsight™ database. Our analysis was restricted to adults diagnosed with epilepsy and who used AED monotherapy. Patients were excluded if they used > 1 type of AED, had < 9 months of treatment, or had a treatment gap of > 60 days. Antiepileptic drugs were classified as LA or SA based on published data and expert opinion. Medical and pharmacy claims were used to estimate health-care utilization and costs, and baseline group differences were adjusted using multivariate analyses.ResultsThere were 4058 (49.6%) LA AED users and 4122 (50.4%) SA AED users. Medication possession ratios (MPRs) were not significantly different between LA AED users and SA AED users (P = 0.125). Long-acting AED users had lower mean overall health-care costs ($9757 vs. $12,689), lower epilepsy-related costs ($3539 vs. $5279), and lower rate of overall (8.8% vs. 10.9%) and epilepsy-related hospitalizations (5.7% vs. 7.6%) compared with SA AED users (all P < 0.01). After adjusting for demographics and clinical characteristics, mean overall costs were lower by $686 and the mean epilepsy-related costs were lower by $894 in LA AED users.ConclusionAlthough MPRs were similar in LA AED and SA AED groups, patients treated with LA monotherapy had a lower economic burden compared with those treated with SA monotherapy, indicating that using AEDs with extended duration of action is associated with decreased health-care use and lower health-care costs.