Adult and pediatric physiologically-based biopharmaceutics modeling to explain lamotrigine immediate release absorption process.

Physiologically-based biopharmaceutics modeling (PBBM) has potential to accelerate the development of new drug and formulations. An important application of PBBM is for special populations such as pediatrics that have pharmacokinetics dependent on the maturation process. Lamotrigine (LTG) is a Biopharmaceutics Classification System (BCS) II drug and is widely prescribed. Therefore, the goal of this study was to assess the biopharmaceutics risk of the low-soluble drug LTG when the ontogeny on gastrointestinal tract (GIT) physiological parameters are considered. An oral physiologically-based pharmacokinetic model and a PBBM were developed and verified using GastroPlus™ software for both adults and children (2-12 years old, 12-52 kg). The biopharmaceutics properties and GIT physiological parameters were evaluated by sensitivity analysis. High doses were simulated assuming a worst case scenario, that is, the dose of 200 mg for adults and 5 mg/kg (up to the maximum of 200 mg) for 2-year-old children. Although several authors have suggested that ontogeny may have an effect on gastrointestinal fluid volume, our study found no evidence of interference between fluid and dose volumes with in vivo dissolution of LTG. The most impactful parameter was found to be the gastric transit time. Therefore, the hypothesis is developed to examine whether LTG exhibits characteristics of a BCS II classification in vitro while showing BCS I-like behavior in vivo. This hypothesis could act as a base for conducting novel studies on model-informed precision dosing, tailored to specific populations and clinical conditions. In addition, it could be instrumental in assessing the influence of various release profiles on in vivo performance for both adult and pediatric populations.

Expression of circulating microRNAs as predictors of diagnosis and surgical outcome in patients with mesial temporal lobe epilepsy with hippocampal sclerosis.

MicroRNAs have been progressively investigated as post-transcriptional regulators playing important roles in epilepsy pathophysiology. Here we investigate three promising microRNAs (miR-27a-3p, miR-328-3p and miR-654-3p) previously described in the literature as possible peripheral biomarkers for epilepsy diagnose and surgical prognosis. Serum samples from 28 patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) were analyzed, 14 with good surgical prognosis (Engel I) and 14 with unfavorable surgical prognosis (Engel III-IV). Serum samples from 11 healthy volunteers were the control group. The microRNAs expression analysis was performed using real-time PCR. The present results did not endorse the role of miR-27a-3p as a peripheral biomarker for epilepsy diagnosis or surgical prognosis. MiR-328-3p, however, presented significant area under the curve (AUC) values when comparing controls to Engel I (90.3%), controls to Engel III-IV (96.8%) and controls to Engel I + Engel III-IV (i.e., epilepsy patients, AUC = 93.5%). Additionally, miR-654-3p displayed AUC = 74.7% when comparing controls to Engel I patients (p = 0.004), and AUC = 73.6% (p = 0.04) in the attempt to discriminate unfavorable from favorable surgical prognosis. In conclusion, the ANOVA and ROC analyzes with the respective AUC, specificity and sensitivity values allows us to conclude that miR-328-3p is the most important peripheral biomarker for the diagnosis of MTLE-HS. In terms of predicting the surgical prognosis of MTLE-HS patients, miR-654-3p proved to be the only microRNA evaluated to present statistical power to differentiate, as a peripheral biomarker, Engel I from Engel III-IV patients.

Modulation of NMDA receptor by miR-219 in the amygdala and hippocampus of patients with mesial temporal lobe epilepsy.

Mesial temporal lobe epilepsy with hippocampal sclerosis is the most frequent form of focal epilepsy in adults, and it is often refractory to drug treatment. Regardless of the efforts on developing new antiepileptic drugs for refractory cases, studies suggest a need for better understanding the molecular bases of epilepsy. The microRNAs have been progressively investigated as potential targets for both epilepsy mechanisms elucidation and treatment. Therefore, the goal of this study was to evaluate the differential expression of miR-219, miR-181b, and miR-195, previously described as regulators of the excitatory neurotransmitter receptors NMDA-R1 and AMPA-GluR2 and inhibitory neurotransmitter GABAA (α2, ß3, and γ2 subunits) in the amygdala and hippocampus of patients with mesial temporal lobe epilepsy. Based on genes and miRNAs' quantitative Polymerase Chain Reaction (qPCR) from 18 patients with epilepsy, our results showed an inverse relationship between miR-219 and NMDA-NR1 expression in both the amygdala and hippocampus in comparison to their expression in controls. NR1 and GluR2 were upregulated in the amygdala of epileptic patients. Low miR-195 expression was observed in the amygdala of patients with epilepsy. Our findings indicate that miR-219 has a possible regulatory role in excitatory neurotransmission in patients with epilepsy, contributing to the new avenue of miRNA biology in drug-resistant epilepsy, reserving huge potential for future applications and clinical interventions in conjunction with existing therapies.

Expression of MicroRNAs miR-145, miR-181c, miR-199a and miR-1183 in the Blood and Hippocampus of Patients with Mesial Temporal Lobe Epilepsy.

The aim of this study was to analyze the expression profiles of the microRNAs (miRNAs) miR-145, miR-181c, miR-199a and miR-1183 in the hippocampus and blood of patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) and to investigate whether these can be used as diagnosis and prognosis biomarkers for epilepsy. Hippocampus and blood samples were collected from 20 patients with MTLE-HS, ten of whom had a favorable surgical outcome (Engel I) and ten with an unfavorable surgical outcome (Engel III-IV). Hippocampus samples from autopsied individuals with no neurological or psychiatric medical history (necropsy samples) and blood samples from healthy individuals were used as controls. Real-time quantitative PCR (RQ-PCR) was used to analyze miRNA expression. The results showed that the expressions of these miRNAs differed quantitatively in the hippocampus and blood of patients with MTLE-HS in comparison to the respective control. This difference was most pronounced for miR-145, which was hypo-expressed in the hippocampus and hyper-expressed in the blood of MTLE-HS patients. MiRNAs miR-145, miR-181c, miR-199a and miR-1183 were hyper-expressed in the blood of patients with MTLE-HS. No statistical differences in the levels of these miRNAs in the blood or hippocampus were found between Engel I patients and Engel III-IV patients. These results suggest that the analyzed microRNAs are potential circulating biomarkers for epilepsy diagnosis.

Qualidade de vida e eventos adversos de pacientes com epilepsia farmacorresistente em uso de lamotrigina / Quality of life and adverse events of patients with drug-resistant epilepsy using lamotrigine

Modelo do estudo: Estudo transversal. Introdução: O tratamento farmacológico é a primeira opção para o tratamento da epilepsia, e cerca de 40% dos pacientes necessitam de politerapia para melhor controle das crises epilépticas, o que pode estar associado ao aumento de eventos adversos e comprometimento da qualidade de vida. Objetivos: Avaliar a qualidade de vida de pacientes com epilepsia farmacoresistente em uso de lamotrigina (LTG), bem como verificar a associação dos eventos adversos dos antiepilépticos com a qualidade de vida. Metodologia: Este estudo transversal foi realizado com 75 pacientes com epilepsia farmacorresistente em uso LTG atendidos em um Ambulatório de Epilepsia de Difícil Controle de Ribeirão Preto-SP, no período de maio/2011 a abril/2012. As variáveis clínicas analisadas foram a qualidade de vida (Quality of Life in Epilepsy - Qolie-31) e o perfil de eventos adversos (AEP ­ Adverse Events Profile Questionnaire). Dados sociodemográficos e farmacoterapêuticos foram coletados através dos prontuários dos pacientes. Este trabalho foi aprovado pelo Comitê de Ética em Pesquisa do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP), cujo número do processo é 8791/2010. Resultados: Os eventos adversos mais frequentes foram sonolência e dificuldade de concentração. Além disso, observou-se baixos escores em todos os domínios relacionados à qualidade de vida (Qolie-31). Conclusão: A qualidade de vida possui associação inversamente significativa com os eventos adversos, nos pacientes em uso de antiepilépticos (p<0,01). (AU)

Study design: Cross-sectional study. Introduction: Pharmacological treatment is the first option to treat epilepsy, and about 40% of patients require polytherapy to better control epileptic seizures, which may be associated with an increase in adverse events and impairment of quality of life. Objective: To evaluate the quality of life of patients with pharmacoresistant epilepsy using lamotrigine (LTG), as well as to verify the association of adverse events with antiepileptic drugs with quality of life. Methods: This cross-sectional study was carried out with 75 patients with drugresistant epilepsy using LTG, in a Clinic of Epilepsy of Difficult Control of Ribeirão Preto-SP, from May/2011 to April / 2012. The clinical variables analyzed were Quality of Life in Epilepsy (QOLIE31) and the Adverse Events Profile Questionnaire (AEP). Socio-demographic and pharmacotherapeutic data were collected through patient records. This study was approved by the Research Ethics Committee of the General Hospital of the Medical School of Ribeirão Preto of the University of São Paulo (HCFMRP-USP), whose case number is 8791/2010. Results: The most frequent adverse events were somnolence and difficulty concentrating. In addition, low scores were observed in all domains related to quality of life (Qolie-31). Conclusion: Quality of life has an inverse association with adverse events in patients using antiepileptic drugs (p <0.01). (AU)

Drug-resistant epilepsy and topiramate: Plasma concentration and frequency of epileptic seizures.

Topiramate (TPM) is a second-generation antiepileptic drug (AED), acting on drug-resistant epilepsy. The aim of the study was to evaluate the influence of the dose, use of other AEDs on TPM plasma concentration (Cp ), and frequency of epileptic seizures. A cross-sectional analytical study was developed with patients aged 18-60 years, for diagnosis of drug-resistant epilepsy, using TPM in monotherapy or associated with other AEDs. The following variables were analyzed: age, frequency of epileptic seizures, pharmacotherapeutic regimen with its respective doses, adherence to medication treatment, and adverse events score. Thirty-seven patients were included, 83.8% of the patients presented Cp below the therapeutic range. Multiple linear regression estimated that the increase of 1.0 mg/kg/d promoted an increase of 0.68 µg/mL in TPMCp , while the use of inducers predicted a reduction of 2.97 µg/mL (P < .001). Multiple Poisson regression predicts that an increase of 1.0 µg/mL in TPMCp decreased the patient's chance of presenting seizures, and patients using AED inducers were about ten times more likely to present seizures than those who do not use (P < .001). In addition, for patients using AED inducers with Cp below the therapeutic range, the mean number of seizures per month was greater than those with Cp within the therapeutic range. The prescribed dose and the use of AED inducers influence Cp of TPM, likewise the low Cp of first-line AEDs and of the adjuvant in the treatment, TPM, as well as low TPM dose seem to affect the control of epileptic seizures.

Influence of the clinical profile of patients with refractory epilepsy on lamotrigine plasma concentration

ABSTRACT The purpose of this work was to evaluate the influence of the clinical profile on lamotrigine (LTG) plasma concentrations from patients with refractory epileptic seizures. In this cross-sectional study, therapeutic monitoring of LTG, and questionnaires with 75 patients with refractory epileptic seizures of a Hospital in Ribeirão Preto-SP-Brazil were performed. The multiple linear regression model was used to verify association between the LTG plasma concentrations and the independent variables. Covariance analysis was used to compare the mean LTG plasma concentration among the co-medication groups. The LTG plasma concentration was associated both with the LTG dosage (mg/kg/day) (p=0.0096) and with the use of first generation antiepileptic drugs (AED) (p<0.01), being carbamazepine (CBZ) and phenytoin (PHT), the AEDs showing the most prominent influence in reducing LTG plasma concentrations. Adverse events, adherence to the pharmacological treatment, and epileptic seizures frequency, did not show significant correlation with LTG plasma concentration values. The conclusion is that LTG plasma concentration is significantly influenced by the LTG dosage and by the concomitant use of a first generation AED.

An investigation of the influence of patient-related factors and comedications on lamotrigine clearance in patients with epilepsy.

Lamotrigine (LTG) is one of the most widely used antiepileptic drugs. Confusion still exists in the literature as to the relative influence of age, body weight, and concomitant drug therapy on LTG pharmacokinetics. So, the objective of this study is to evaluate the influence of patient-related factors and comedication on LTG apparent oral clearance (CL/F). A therapeutic drug-monitoring database was used to identify steady-state plasma LTG concentrations in 210 patients. LTG CL/F values were calculated for each patient according to the equation CL/F (L/h per kg) = LTG daily dose (mg/kg)/Css (steady state concentration) (mg/L) × 24 h. A linear-regression model was used to assess the influence of gender, dose, age, and body weight in LTG CL/F. The influence of comedication on LTG CL/F was investigated by applying the Bonferroni post-test. The lowest LTG CL/F was found in patients comedicated with valproate (VPA) (mean, 0.0183 L/h per kg), followed by patients receiving VPA + enzyme inducers (0.0271 L/h per kg), patients on LTG monotherapy (0.0298 L/h per kg) and patients comedicated with enzyme inducers (0.056 L/h per kg) LTG CL/F correlated significantly with LTG dose (P < 0.01), but showed no significant relationship with gender, weight, and age. LTG CL/F is influenced by the type of antiepileptic comedication. The correlation with dose may be a spurious finding related to the fact that physicians, in adjusting dosage according to clinical response, are more likely to use larger doses in patients with high clearance values.

Stir bar-sorptive extraction, solid phase extraction and liquid-liquid extraction for levetiracetam determination in human plasma: comparing recovery rates / Extração sortiva em barra de agitação, extracção da fase sólida e de extracção líquido-líquido para a determinação de levetiracetam em plasma humano: comparando as taxas de recuperação

Levetiracetam (LEV), an antiepileptic drug (AED) with favorable pharmacokinetic profile, is increasingly being used in clinical practice, although information on its metabolism and disposition are still being generated. Therefore a simple, robust and fast liquid-liquid extraction (LLE) followed by high-performance liquid chromatography method is described that could be used for both pharmacokinetic and therapeutic drug monitoring (TDM) purposes. Moreover, recovery rates of LEV in plasma were compared among LLE, stir bar-sorptive extraction (SBSE), and solid-phase extraction (SPE). Solvent extraction with dichloromethane yielded a plasma residue free from usual interferences such as commonly co-prescribed AEDs, and recoveries around 90% (LLE), 60% (SPE) and 10% (SBSE). Separation was obtained using reverse phase Select B column with ultraviolet detection (235 nm). Mobile phase consisted of methanol:sodium acetate buffer 0.125 M pH 4.4 (20:80, v/v). The method was linear over a range of 2.8-220.0 µg mL^-1. The intra- and inter-assay precision and accuracy were studied at three concentrations; relative standard deviation was less than 10%. The limit of quantification was 2.8 µg mL^-1. This robust method was successfully applied to analyze plasma samples from patients with epilepsy and therefore might be used for pharmacokinetic and TDM purposes...

Levetiracetam, fármaco antiepiléptico com perfil farmacocinético favorável, tem sido cada vez mais utilizado na prática clínica, embora informações sobre seu metabolismo e disposição cinética ainda estejam sendo geradas. Um método simples, robusto e rápido de extração líquido-líquido seguido por análise por cromatografia líquida de alta eficiência é aqui descrito para servir tanto a investigações farmacocinéticas quanto à monitorização terapêutica. Além disso, as taxas de recuperação do levetiracetam em plasma foram comparadas entre a extração líquido-líquido, a extração sortiva em barra de agitação e a extração em fase sólida. Extração com o solvente diclorometano resultou em plasma livre de interferentes, tais como fármacos antiepilépticos co-prescritos, e apresentou taxas de recuperação em torno de 90% (extração líquido-líquido), 60% (extração em fase sólida) e 10% (extração sortiva em barra de agitação). A separação foi obtida utilizando-se coluna de fase reversa Select B e detecção ultravioleta (235 nm). A fase móvel foi composta por metanol:tampão acetato de sódio 0,125 M pH 4,4 (20:80, v/v). O método mostrou-se linear para o intervalo de 2,8 a 220,0 µg mL^-1. Precisão intra- e interdias e a exatidão foram avaliadas em três concentrações; o desvio padrão relativo foi inferior a 10%. O limite de quantificação foi 2.8 µg mL^-1. Este método foi aplicado para análise de amostras de plasma de pacientes com epilepsia e, desta forma, pode ser utilizado satisfatoriamente tanto para fins de farmacocinética quanto de monitorização terapêutica...

The social context and the need of information from patients with epilepsy: evaluating a tertiary referral service.

OBJECTIVE: Characterize the social profile and the need of information from patients with refractory epilepsy. METHOD: A semi-structured questionnaire was applied to 103 patients to investigate sociodemographic aspects, pharmacotherapy and any doubts about epilepsy. RESULTS: Patients were highly dependent on having a free and accessible supply of antiepileptic drugs. Sixty-eight percent of the population was unemployed, and 26% confirmed receiving social security benefits due to epilepsy. Twenty-nine percent of the population reached high school. Eighty-five percent of the patients had at least one doubt about epilepsy; treatment and epilepsy aspects in general were the main topics. CONCLUSION: As observed in developed countries, patients with refractory epilepsy from a developing country also have high rates of unemployment and low educational levels. The results raise a concern about the need of information about epilepsy by patients and their families, urging the necessity to invest in strategies to solve this deficiency in knowledge.

The social context and the need of information from patients with epilepsy: evaluating a tertiary referral service / O contexto social e a necessidade de informações de pacientes com epilepsia: avaliando um serviço terciário de referência

Objective Characterize the social profile and the need of information from patients with refractory epilepsy. Method A semi-structured questionnaire was applied to 103 patients to investigate sociodemographic aspects, pharmacotherapy and any doubts about epilepsy. Results Patients were highly dependent on having a free and accessible supply of antiepileptic drugs. Sixty-eight percent of the population was unemployed, and 26% confirmed receiving social security benefits due to epilepsy. Twenty-nine percent of the population reached high school. Eighty-five percent of the patients had at least one doubt about epilepsy; treatment and epilepsy aspects in general were the main topics. Conclusion : As observed in developed countries, patients with refractory epilepsy from a developing country also have high rates of unemployment and low educational levels. The results raise a concern about the need of information about epilepsy by patients and their families, urging the necessity to invest in strategies to solve this deficiency in knowledge. .

Objetivo : Caracterizar o perfil social e a necessidade de informações por parte de pacientes com epilepsia refratária. Método Um questionário semi-estruturado foi aplicado a 103 pacientes para investigar aspectos sociodemográficos, farmacoterapia e quaisquer dúvidas sobre epilepsia. Resultados Os pacientes mostraram-se altamente dependentes de um fornecimento gratuito e acessível de drogas antiepilépticas. Sessenta e oito por cento da população estava desempregada, e 26% confirmaram receber algum benefício social devido à epilepsia. Vinte e nove por cento da população alcançou ensino médio. Oitenta e cinco por cento dos pacientes tinha ao menos uma dúvida sobre epilepsia; tratamento e aspectos gerais da epilepsia foram os principais temas. Conclusão Tal qual observado em países desenvolvidos, pacientes com epilepsia refratária em países em desenvolvimento também apresentam altas taxas de desemprego e baixos níveis educacionais. Os resultados são preocupantes no que diz respeito à necessidade de informações sobre epilepsia por parte dos pacientes e seus familiares, apontando a necessidade de se investir em estratégias que solucionem esta deficiência de conhecimento. .

Drug utilization profile in adult patients with refractory epilepsy at a tertiary referral center / Perfil de utilizacao de farmacos por pacientes adultos com epilepsia refrataria em um centro terciario de referencia

Objective To evaluate the utilization profile of antiepileptic drugs in a population of adult patients with refractory epilepsy attending a tertiary center. Method Descriptive analyses of data were obtained from the medical records of 112 patients. Other clinical and demographic characteristics were also registered. Results Polytherapies with ≥3 antiepileptic drugs were prescribed to 60.7% of patients. Of the old agents, carbamazepine and clobazam were the most commonly prescribed (72.3% and 58.9% of the patients, respectively). Among the new agents, lamotrigine was the most commonly prescribed (36.6% of the patients). At least one old agent was identified in 103 out of the 104 polytherapies, while at least one new agent was prescribed to 70.5% of the population. The most prevalent combination was carbamazepine + clobazam + lamotrigine. The mean AED load found was 3.3 (range 0.4–7.7). Conclusion The pattern of use of individual drugs, although consistent with current treatment guidelines, is strongly influenced by the public health system. .

Objetivo Avaliar o perfil de utilização de fármacos antiepilépticos em uma população de pacientes adultos com epilepsia refratária atendidos em um centro terciário. Método Análises descritivas dos dados obtidos dos registros médicos de 112 pacientes. Também foram consideradas as características clínicas e demográficas. Resultados Foram prescritas politerapias com ≥3 antiepilépticos a 60,7% dos pacientes. Em relação aos fármacos de primeira geração, carbamazepina e clobazam foram os mais frequentemente prescritos (a 72,3% e 58,9% dos pacientes, respectivamente). Dentre os novos antiepilépticos, a lamotrigina foi o mais prescrito (36,6% dos pacientes). Ao menos um antiepiléptico de primeira geração foi encontrado em 103 das 104 politerapias; ao menos um novo antiepiléptico foi prescrito a 70,5% da população. A combinação mais prevalente foi carbamazepina+clobazan+lamotrigina. A carga média de antiepilépticos foi 3.3 (0.4 a 7.7). Conclusão O padrão de utilização de antiepilépticos, embora concordante com guias atuais, é fortemente influenciado pelo sistema público de saúde. .

Lamotrigine therapeutic drug monitoring in a tertiary epilepsy centre / Monitorização terapêutica da lamotrigina em um centro terciário de epilepsia

Objective: to review the experience with lamotrigine therapeutic drug monitoring in a tertiary epilepsy centre aiming to characterize the plasma concentrations profile. Methods: inclusion of adults and children to whom lamotrigine concentrations were requested from October 2008 to April 2010. A chromatographic method was validated to determine lamotrigine concentrations. Reference range adopted (plasma): 2.5-15.0 mg/L. Results: 115 patients were included (86 adults, 29 children). Mean±standard deviation lamotrigine dosages for adults and children were statistically different (5.1±2.0 versus 7.4±3.4 mg/kg/day respectively, p<0.0001), so as lamotrigine concentrations (5.13±4.0 versus 9.0±5.6 mg/L respectively, p=0.0006). Approximately 68% of all quantifications were within the reference range. From the 29 quantifications below 2.5 mg/L, 27 corresponded to lamotrigine+enzyme inducers therapies. There was no correlation between lamotrigine concentrations and dosages neither for pediatric nor for adult groups. Patients on monotherapy had lamotrigine concentrations significantly higher than those on lamotrigine+inducers therapies (p<0.001), and patients on lamotrigine+valproic acid therapy had lamotrigine concentrations higher than those on lamotrigine+inducers (p<0.001). There was no significant difference among mean dosages according to different comedications. Conclusion: our observations about the influence of polytherapies on lamotrigine pharmacokinetics confirm the relevance of quantifying this antiepileptic drug plasma concentrations in the process of treatment optimization...

Objetivo: revisar a experiência de um centro terciário de epilepsia com a monitorização terapêutica da lamotrigina objetivando caracterizar o perfil de concentrações plasmáticas encontradas. Métodos: inclusão de todos adultos e crianças para os quais solicitou-se quantificação plasmáticas de lamotrigina de Outubro/2008 a Abril/2010. Um método cromatográfico foi validado para determinar as concentrações de lamotrigina. Intervalo de referência adotado (plasma): 2.5-15.0 mg/L. Resultados: 115 pacientes foram incluídos (86 adultos, 29 crianças). Média±desvio-padrão das doses de lamotrigina para adultos e crianças foram significativamente diferentes (5.1±2.0 versus 7.4±3.4 mg/kg/dia respectivamente, p<0.0001), assim como as concentrações (5.13±4.0 versus 9.0±5.6 mg/L, p=0.0006). Aproximadamente 68% das quantificações estavam dentro do intervalo de referência. Das 29 quantificações abaixo de 2.5 mg/L, 27 correspondiam a associações lamotrigina+indutores enzimáticos. Não houve correlação entre concentrações e doses de lamotrigina. Pacientes em monoterapia tiveram concentrações de lamotrigina significativamente maiores do que pacientes utilizando lamotrigina+indutores enzimáticos (p<0.001); pacientes em uso de lamotrigina+ácido valproico apresentaram concentrações maiores comparativamente àqueles em uso de lamotrigina+indutores (p<0.001). Não houve diferença significativa entre doses médias de acordo com diferentes comedicações. Conclusão: a influência de politerapias sobre a farmacocinética da lamotrigina confirma a relevância dese quantificar as concentrações plasmáticas deste antiepilético no processo de otimização terapêutica...

Drug utilization profile in adult patients with refractory epilepsy at a tertiary referral center.

OBJECTIVE: To evaluate the utilization profile of antiepileptic drugs in a population of adult patients with refractory epilepsy attending a tertiary center. METHOD: Descriptive analyses of data were obtained from the medical records of 112 patients. Other clinical and demographic characteristics were also registered. RESULTS: Polytherapies with ≥3 antiepileptic drugs were prescribed to 60.7% of patients. Of the old agents, carbamazepine and clobazam were the most commonly prescribed (72.3% and 58.9% of the patients, respectively). Among the new agents, lamotrigine was the most commonly prescribed (36.6% of the patients). At least one old agent was identified in 103 out of the 104 polytherapies, while at least one new agent was prescribed to 70.5% of the population. The most prevalent combination was carbamazepine + clobazam + lamotrigine. The mean AED load found was 3.3 (range 0.4-7.7). CONCLUSION: The pattern of use of individual drugs, although consistent with current treatment guidelines, is strongly influenced by the public health system.

Addressing overtreatment in patients with refractory epilepsy at a tertiary referral centre in Brazil.

BACKGROUND: Patients with refractory epilepsy often have impaired quality of life (QOL) as a consequence of seizures and adverse effects of antiepileptic drugs. We assessed the impact of adverse effects on QOL and the utility of a structured instrument to help the physician manage adverse effects in patients with refractory epilepsy. METHODS: Clinical characteristics, drug treatment and adverse effects were evaluated in 102 patients with refractory epilepsy at a single tertiary referral centre. The Adverse Events Profile (AEP) and Quality of Life in Epilepsy-31 (QOLIE-31) questionnaires were completed at baseline and after six months. At baseline, patients with a high burden of adverse effects (AEP scores ≥45) were randomized to an intervention or control group. AEP scores in the intervention group were available to the physician as an instrument to help to reduce adverse effects. RESULTS: Ninety-five patients (93.1%) were on polytherapy. Sixty-six completed the questionnaires and, of these, 43 (65.1%) had a high AE burden and were randomized to the intervention and control group. QOLIE-31 scores were inversely correlated with AEP scores at both visits. Among randomized patients, AEP scores tended to decrease between the baseline and the final visit without significant differences between groups (intervention group: 54.1 ±â€Š6.1 vs 51.1 ±â€Š9.1; control group: 55.8 ±â€Š5.8 vs 50.5 ±â€Š12.2). QOLI-31 scores did not change substantially between visits (intervention group: 45.9 ±â€Š17.4 vs 48.4 ±â€Š14; control group: 47.5 ±â€Š15.7 vs 45.2 ±â€Š18.9). CONCLUSION: A significant proportion of patients had a high toxicity burden which had an impact on their QOL. Reduction of overtreatment is a difficult challenge which cannot be addressed solely by providing a structured assessment of adverse effects, but requires a more comprehensive approach aimed at optimizing the many components of the management strategy.

Influence of enzyme inducing antiepileptic drugs on the pharmacokinetics of levetiracetam in patients with epilepsy.

To assess whether levetiracetam elimination is influenced by enzyme inducing antiepileptic drugs (EIAEDs), serum levetiracetam levels were determined at frequent intervals after a single oral 1000mg dose in 15 subjects co-medicated with EIAEDs and 15 matched controls. The EIAED group showed a higher levetiracetam oral clearance (p=0.01) and a shorter half-life (p=0.02) than controls. Although the magnitude of interaction is relatively modest, it could have clinical significance for some patients.