Gus A. Baker

The SANAD study of effectiveness of carbamazepine, gabapentin, lamotrigine, oxcarbazepine, or topiramate for treatment of partial epilepsy: an unblinded randomised controlled trial

BACKGROUND Carbamazepine is widely accepted as a drug of first choice for patients with partial onset seizures. Several newer drugs possess efficacy against these seizure types but previous randomised controlled trials have failed to inform a choice between these drugs. We aimed to assess efficacy with regards to longer-term outcomes, quality of life, and health economic outcomes. METHODS SANAD was an unblinded randomised controlled trial in hospital-based outpatient clinics in the UK. Arm A recruited 1721 patients for whom carbamazepine was deemed to be standard treatment, and they were randomly assigned to receive carbamazepine, gabapentin, lamotrigine, oxcarbazepine, or topiramate. Primary outcomes were time to treatment failure, and time to 12-months remission, and assessment was by both intention to treat and per protocol. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN38354748. FINDINGS For time to treatment failure, lamotrigine was significantly better than carbamazepine (hazard ratio [HR] 0.78 [95% CI 0.63-0.97]), gabapentin (0.65 [0.52-0.80]), and topiramate (0.64 [0.52-0.79]), and had a non-significant advantage compared with oxcarbazepine (1.15 [0.86-1.54]). For time to 12-month remission carbamazepine was significantly better than gabapentin (0.75 [0.63-0.90]), and estimates suggest a non-significant advantage for carbamazepine against lamotrigine (0.91 [0.77-1.09]), topiramate (0.86 [0.72-1.03]), and oxcarbazepine (0.92 [0.73-1.18]). In a per-protocol analysis, at 2 and 4 years the difference (95% CI) in the proportion achieving a 12-month remission (lamotrigine-carbamazepine) is 0 (-8 to 7) and 5 (-3 to 12), suggesting non-inferiority of lamotrigine compared with carbamazepine. INTERPRETATION Lamotrigine is clinically better than carbamazepine, the standard drug treatment, for time to treatment failure outcomes and is therefore a cost-effective alternative for patients diagnosed with partial onset seizures.

Quality of Life of People with Epilepsy: A European Study

Summary: Purpose: To study the impact of epilepsy and its treatment on people with epilepsy in Europe. We therefore aimed to collect data from as many countries as possible.

The SANAD study of effectiveness of valproate, lamotrigine, or topiramate for generalised and unclassifiable epilepsy: an unblinded randomised controlled trial.

BACKGROUND Valproate is widely accepted as a drug of first choice for patients with generalised onset seizures, and its broad spectrum of efficacy means it is recommended for patients with seizures that are difficult to classify. Lamotrigine and topiramate are also thought to possess broad spectrum activity. The SANAD study aimed to compare the longer-term effects of these drugs in patients with generalised onset seizures or seizures that are difficult to classify. METHODS SANAD was an unblinded randomised controlled trial in hospital-based outpatient clinics in the UK. Arm B of the study recruited 716 patients for whom valproate was considered to be standard treatment. Patients were randomly assigned to valproate, lamotrigine, or topiramate between Jan 12, 1999, and Aug 31, 2004, and follow-up data were obtained up to Jan 13, 2006. Primary outcomes were time to treatment failure, and time to 1-year remission, and analysis was by both intention to treat and per protocol. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN38354748. FINDINGS For time to treatment failure, valproate was significantly better than topiramate (hazard ratio 1.57 [95% CI 1.19-2.08]), but there was no significant difference between valproate and lamotrigine (1.25 [0.94-1.68]). For patients with an idiopathic generalised epilepsy, valproate was significantly better than both lamotrigine (1.55 [1.07-2.24] and topiramate (1.89 [1.32-2.70]). For time to 12-month remission valproate was significantly better than lamotrigine overall (0.76 [0.62-0.94]), and for the subgroup with an idiopathic generalised epilepsy 0.68 (0.53-0.89). But there was no significant difference between valproate and topiramate in either the analysis overall or for the subgroup with an idiopathic generalised epilepsy. INTERPRETATION Valproate is better tolerated than topiramate and more efficacious than lamotrigine, and should remain the drug of first choice for many patients with generalised and unclassified epilepsies. However, because of known potential adverse effects of valproate during pregnancy, the benefits for seizure control in women of childbearing years should be considered.

The Clinical Course of Epilepsy and Its Psychosocial Correlates: Findings from a U.K. Community Study

As part of a large community‐based study, we retrospectively examined the clinical course of epilepsy in an unselected population of people who had a recent history of seizures or were receiving antiepileptic drugs (AEDs). Clinical information was collected from medical records, and information about psychosocial functioning was obtained by means of postal questionnaires sent to identified subjects. The response rate to the postal questionnaire was 71%. There were some deficiencies in the recording of clinical data, which is not unusual since data were taken from records held by primary physicians rather than from hospital clinics. Nevertheless, findings regarding the clinical course of epilepsy corresponded to those of earlier studies. Fifty‐seven percent of the sample had had at least a 2‐year seizure‐free period and 46% of subjects were currently in a remission of at least 2‐year duration. There was a clear relationship between current seizure frequency and levels of anxiety and depression, perceived impact of epilepsy, perceived stigma, and marital and employment status. The relationship of seizure frequency and other clinical variables to psychosocial function was explored by multivariate analysis techniques. The amount of variation in scores on the various measures of function accounted for by the clinical variables was small. The most important predictor was current seizure activity, which was the first variable to enter the regression analyses for six of the eight measures of psychosocial function considered. Age at epilepsy onset also emerged as a significant predictor for depression, stigma, and marital status. In individuals with epilepsy in remission, there was little evidence that psychosocial functioning was associated with length of remission, a finding which may in part reflect the nature of this study population. The results indicate that there are several more important predictors of psychopathology and social dysfunction in epilepsy and suggest several implications for treatment interventions.

Cognitive function at 3 years of age after fetal exposure to antiepileptic drugs

BACKGROUND Fetal exposure of animals to antiepileptic drugs at doses lower than those required to produce congenital malformations can produce cognitive and behavioral abnormalities, but cognitive effects of fetal exposure of humans to antiepileptic drugs are uncertain. METHODS Between 1999 and 2004, we enrolled pregnant women with epilepsy who were taking a single antiepileptic agent (carbamazepine, lamotrigine, phenytoin, or valproate) in a prospective, observational, multicenter study in the United States and the United Kingdom. The primary analysis is a comparison of neurodevelopmental outcomes at the age of 6 years after exposure to different antiepileptic drugs in utero. This report focuses on a planned interim analysis of cognitive outcomes in 309 children at 3 years of age. RESULTS At 3 years of age, children who had been exposed to valproate in utero had significantly lower IQ scores than those who had been exposed to other antiepileptic drugs. After adjustment for maternal IQ, maternal age, antiepileptic-drug dose, gestational age at birth, and maternal preconception use of folate, the mean IQ was 101 for children exposed to lamotrigine, 99 for those exposed to phenytoin, 98 for those exposed to carbamazepine, and 92 for those exposed to valproate. On average, children exposed to valproate had an IQ score 9 points lower than the score of those exposed to lamotrigine (95% confidence interval [CI], 3.1 to 14.6; P=0.009), 7 points lower than the score of those exposed to phenytoin (95% CI, 0.2 to 14.0; P=0.04), and 6 points lower than the score of those exposed to carbamazepine (95% CI, 0.6 to 12.0; P=0.04). The association between valproate use and IQ was dose dependent. Childrens IQs were significantly related to maternal IQs among children exposed to carbamazepine, lamotrigine, or phenytoin but not among those exposed to valproate. CONCLUSIONS In utero exposure to valproate, as compared with other commonly used antiepileptic drugs, is associated with an increased risk of impaired cognitive function at 3 years of age. This finding supports a recommendation that valproate not be used as a first-choice drug in women of childbearing potential.

The longer term outcome of children born to mothers with epilepsy

Objectives: To determine the prevalence of cognitive delay and possible associated dysmorphic features in children exposed to antiepileptic drugs (AEDs) in utero. Design: Retrospective study of children born to mothers with epilepsy. Setting: Regional epilepsy clinics in Liverpool and Manchester, UK. Participants: Children aged between 6 months and 16 years born to mothers with epilepsy. Main outcome measures: Structured interviews, hospital records, clinical examination, and psychometric tests (Wechsler) were used to assess exposure and intelligence quotient (IQ). Blinded assessment of photographs was used to score children with characteristic dysmorphic features. Results: A total of 249 children aged 6 and over were studied: 41 were exposed to sodium valproate, 52 to carbamazepine, 21 to phenytoin, 49 to polytherapy, and 80 were unexposed. Mean verbal IQ was significantly lower in the valproate group compared to unexposed and other monotherapy groups. Multiple regression analysis showed that both valproate exposure and frequent tonic-clonic seizures in pregnancy were significantly associated with a lower verbal IQ despite adjusting for other confounding factors. There was a significant negative correlation between dysmorphic features and verbal IQ in children exposed to valproate. Conclusions: This study identifies valproate as a drug carrying potential risks for developmental delay and cognitive impairment and is the first to suggest that frequent tonic-clonic seizures have a similar effect. Our results need to be interpreted with caution given their retrospective nature. Women with epilepsy need careful counselling about individual risk benefit of AED treatment before pregnancy.

Fetal antiepileptic drug exposure and cognitive outcomes at age 6 years (NEAD study): a prospective observational study

BACKGROUND Many women of childbearing potential take antiepileptic drugs, but the cognitive effects of fetal exposure are uncertain. We aimed to assess effects of commonly used antiepileptic drugs on cognitive outcomes in children up to 6 years of age. METHODS In this prospective, observational, assessor-masked, multicentre study, we enrolled pregnant women with epilepsy on antiepileptic drug monotherapy (carbamazepine, lamotrigine, phenytoin, or valproate) between October, 1999, and February, 2004, at 25 epilepsy centres in the UK and the USA. Our primary outcome was intelligence quotient (IQ) at 6 years of age (age-6 IQ) in all children, assessed with linear regression adjusted for maternal IQ, antiepileptic drug type, standardised dose, gestational birth age, and use of periconceptional folate. We also assessed multiple cognitive domains and compared findings with outcomes at younger ages. This study is registered with ClinicalTrials.gov, number NCT00021866. FINDINGS We included 305 mothers and 311 children (six twin pairs) in the primary analysis. 224 children completed 6 years of follow-up (6-year-completer sample). Multivariate analysis of all children showed that age-6 IQ was lower after exposure to valproate (mean 97, 95% CI 94-101) than to carbamazepine (105, 102-108; p=0·0015), lamotrigine (108, 105-110; p=0·0003), or phenytoin (108, 104-112; p=0·0006). Children exposed to valproate did poorly on measures of verbal and memory abilities compared with those exposed to the other antiepileptic drugs and on non-verbal and executive functions compared with lamotrigine (but not carbamazepine or phenytoin). High doses of valproate were negatively associated with IQ (r=-0·56, p<0·0001), verbal ability (r=-0·40, p=0·0045), non-verbal ability (r=-0·42, p=0·0028), memory (r=-0·30, p=0·0434), and executive function (r=-0·42, p=0·0004), but other antiepileptic drugs were not. Age-6 IQ correlated with IQs at younger ages, and IQ improved with age for infants exposed to any antiepileptic drug. Compared with a normative sample (173 [93%] of 187 children), right-handedness was less frequent in children in our study overall (185 [86%] of 215; p=0·0404) and in the lamotrigine (59 [83%] of 71; p=0·0287) and valproate (38 [79%] of 40; p=0·0089) groups. Verbal abilities were worse than non-verbal abilities in children in our study overall and in the lamotrigine and valproate groups. Mean IQs were higher in children exposed to periconceptional folate (108, 95% CI 106-111) than they were in unexposed children (101, 98-104; p=0·0009). INTERPRETATION Fetal valproate exposure has dose-dependent associations with reduced cognitive abilities across a range of domains at 6 years of age. Reduced right-handedness and verbal (vs non-verbal) abilities might be attributable to changes in cerebral lateralisation induced by exposure to antiepileptic drugs. The positive association of periconceptional folate with IQ is consistent with other recent studies.

Outcomes of Add-on Treatment with Lamotrigine in Partial Epilepsy

Summary: The need for new antiepileptic drugs (AEDs) and more sensitive methods of assessing their efficacy is well recognized. This study was designed to evaluate the efficacy and safety of lamotrigine (LTG), a potential new AED and to develop and test new outcome measures. A health‐related quality of life (HRQL) model was developed which contains previously validated measures of anxiety, depression, happiness, overall mood, self‐esteem, and mastery and a specifically designed seizure severity scale with patient‐ and caregiver‐based components. This HRQL model was used in a randomized, placebo‐controlled, double‐blind, cross‐over study of LTG in 81 patients with refractory partial seizures. Seizure frequency was the primary measure and seizure severity and the HRQL were secondary measures of efficacy. The reduction in seizure frequency with LTG, relative to placebo, was 29.7% [95% confidence interval (CI) 17.8%, 39.9%] for total seizure count, 33.4% (95% CI 14.8%, 47.9%) for complex partial seizures (CPS) and 20.3% (95% CI 0.3%, 36.2%) for secondarily generalized tonic‐clonic seizures (GTCS). However, although 41 patients elected to continue with LTG, only 11 experienced at least 50% reduction in total seizures, indicating that other factors influenced their decision. The score with LTG, relative to placebo, was significantly lower for the ictal (p = 0.017) and caregivers (p = 0.035) subscales of the seizure severity scale and significantly higher for happiness (p = 0.003) and mastery (p = 0.003). Simple correlation and multiple‐regression analyses indicate that the effects on seizure frequency, seizure severity, and psychological variables appear to be independent of each other. This study indicates that LTG is effective in reducing seizure frequency and has additional favorable effects on seizure severity, mood, and perceived internal control. Some of the scales used indicate the potential of secondary measures of efficacy to enhance the sensitivity of trials of new AEDs.

Epilepsy and social identity: the stigma of a chronic neurological disorder

Epilepsy is the most common serious neurological disorder worldwide, affecting about 50 million people. In most people with epilepsy, the disorder is clinically benign. However, because of the stigma associated with having epilepsy, which is common to many cultures, there can be a negative effect on the social identity of people with the disorder, particularly for those living in resource-poor countries. In this paper, we present general theories of stigma, as well as those specific to chronic illness. We relate these theories to the stigma associated with epilepsy throughout history and across cultures. We review research on the relation between stigma and the overall quality of life of people with epilepsy. Finally, we address reduction of the stigma.

The stigma of epilepsy: a European perspective.

Summary: Purpose: To study the stigma of epilepsy in a European sample.