Are there potential problems with generic substitution of antiepileptic drugs?

In response to increasing cost pressures, healthcare systems are encouraging the use of generic medicines. This review explores potential problems with generic substitution of antiepileptic drugs (AEDs). A broad search strategy identified approximately 70 relevant articles. Potential problems with generic substitution included: The limited evidence (mainly case reports with some pharmacokinetic studies) appears to support these concerns for older AEDs. As a result, restrictions on use of specific generic AEDs are in place in some countries and recommended by some lay epilepsy organisations. As more AEDs lose patent protection, it is important to examine the question of whether generic substitution may pose problems for patients with epilepsy, and whether there should be safeguards to ensure that both physician and patient are informed when generic substitution occurs.

The clinical effectiveness and cost-effectiveness of newer drugs for children with epilepsy. A systematic review

OBJECTIVES

To examine the clinical effectiveness and cost-effectiveness of newer antiepileptic drugs (AEDs) for epilepsy in children: gabapentin, lamotrigine, levetiracetam, oxcarbazepine, tiagabine, topiramate and vigabatrin.

DATA SOURCES

Electronic databases. Drug company submissions.

REVIEW METHODS

For the systematic review of clinical and cost-effectiveness, studies were assessed for inclusion according to predefined criteria. Data extraction and quality assessment were also undertaken. A decision-analytic model was constructed to estimate the cost-effectiveness of the newer agents in children with partial seizures, the only condition where there were sufficient trial data to inform a model.

RESULTS

The quality of the randomised controlled trial (RCT) data was generally poor. For each of the epilepsy subtypes considered in RCTs identified for this review (partial epilepsy with or without secondary generalisation, Lennox-Gastaut syndrome, infantile spasms, absence epilepsy and benign epilepsy with centrotemporal spikes), there is some evidence from placebo-controlled trials that the newer agents tested are of some value in the treatment of these conditions. Where active controls have been used, the limited evidence available does not indicate a difference in effectiveness between newer and older drugs. The data are not sufficient to inform a prescribing strategy for any of the newer agents in any of these conditions. In particular, there is no clinical evidence to suggest that the newer agents should be considered as a first-choice treatment in any form of epilepsy in children. Annual drug costs of the newer agents ranges from around 400 pound to 1200 pound, depending on age and concomitant medications. An AED that is ineffective or has intolerable side-effects will only be used for a short period of time, and many patients achieving seizure freedom will successfully withdraw from drug treatment without relapsing. The results of the decision-analytic model do not suggest that the use of the newer agents in any of the scenarios considered is clearly cost-effective but, similarly, do not indicate that they are clearly not cost-effective.

CONCLUSIONS

The prognosis for children diagnosed with epilepsy is generally good, with a large proportion responding well to the first treatment given. A substantial proportion, however, will not respond well to treatment, and for these patients the clinical goal is to find an optimal balance between the benefits and side-effects of any treatment given. For the newly, or recently, diagnosed population, the key question for the newer drugs is how soon they should be tried. The cost-effectiveness of using these agents early, in place of one of the older agents, will depend on the effectiveness and tolerability of these agents compared with the older agents; the evidence from the available trial data so far suggests that the newer agents are no more effective but may be somewhat better tolerated than the older agents, and so the cost-effectiveness for early use will depend on the trade-off between effectiveness and tolerability, both in terms of overall (long-term) treatment retention and overall utility associated with effects on seizure rate and side-effects. There are insufficient data available to estimate accurately the nature of this trade off either in terms of long-term treatment retention or utility. Better information is required from RCTs before any rational evidence-based prescribing strategy could be developed. Ideally, RCTs should be conducted from a 'public health' perspective, making relevant comparisons and incorporating outcomes of interest to clinicians and patients, with sufficiently long-term follow-up to determine reliably the clinical utility of different treatments, particularly with respect to treatment retention and the balance between effectiveness and tolerability. RCTs should mirror clinical practice with respect to diagnosis, focusing on defined syndromes or, where no syndrome is identified, on groups defined by specific seizure type(s) and aetiology. Epilepsy in children is a complex disease, with a variety of distinct syndromes and many alternative treatment options and outcomes. Diagnosis-specific decision-analytic models are required; further research may be required to inform parameter values adequately with respect to epidemiology and clinical practice.

[Cost-minimisation analysis of the pharmacological treatment of epilepsy in Spain]

AIM

To use a model of economic evaluation to analyse the efficiency of therapy with the antiepileptic drugs indicated in recently diagnosed partial and generalised epilepsy.

MATERIALS AND METHODS

The treatment of partial epilepsy and generalised epilepsy in Spain was taken as the basis to design two flexible simulation models of the decision tree type. The time horizon of the study was one year and the perspective was that of the Spanish National Health System, and indirect costs were also included. Clinical effectiveness data were obtained from a review of the literature on clinical trials. Information about resources was obtained from the opinions of a panel of experts. Unitary costs of resources were drawn from Spanish databases (euro 2003). The findings of the study were expressed in terms of average cost per patient with each therapeutic strategy, as well as the incremental cost of the different treatment strategies with respect to valproic acid.

RESULTS

According to the literature that was reviewed, there are no differences in effectiveness from one antiepileptic drug to another. The incremental cost of the different therapeutic strategies, with respect to valproic acid, lies between 211 and 911 euros per patient and year in partial epilepsy, and between 1,355 and 1,297 euros per patient and year in the case of generalised epilepsy.

CONCLUSIONS

The use of sustained-release valproic acid in recently diagnosed partial and generalised epilepsy would allow savings to be made in resources, with respect to the other antiepileptic drugs, and can therefore be considered to be the most effective therapeutic option.

Deprivation and incidence of epilepsy in children

OBJECTIVE

To determine differences in the incidence of epilepsy associated with deprivation.

DESIGN

Cross-sectional study of new cases of epilepsy presenting over 3 years linked to census based population and deprivation data.

SETTING

Norfolk UK.

PATIENTS

Children aged 29 days to 14 years presenting to the only district hospital serving the study area.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Incidence of epilepsy in quartiles of areas defined by Townsend deprivation score.

RESULTS

Overall annual incidence of epilepsy was 6.63 cases per 10,000. There was no association between epilepsy incidence and deprivation with rates of 6.5, 8.0, 4.1 and 7.9 per 10,000 per year, respectively, in areas with increasing levels of deprivation. Proportions of children investigated for possible epilepsy and of children treated for epilepsy showed no social variation.

CONCLUSIONS

We did not find social inequalities in the incidence of epilepsy in children. Nor was there evidence for the inverse care law in the investigation or treatment of epilepsy in children.

Cost-effectiveness of add-on lamotrigine therapy in clinical practice

OBJECTIVE

This retrospective study addresses the cost-effectiveness of add-on therapy with lamotrigine in clinical practice.

METHODS

Two years' observational data of 165 patients were used. Seizure frequency, adverse effects and direct medical costs were recorded for the year before and the year after the start of lamotrigine add-on therapy. Therapy effectiveness was measured by: (1) reduction in seizure frequency and (2) retention time. The incremental cost-effectiveness ratio expressed the direct medical cost per patient treated effectively with lamotrigine.

RESULTS

The cost of medication was 492 (95% CI: 399-583) higher after the start of lamotrigine therapy. The extra cost of lamotrigine therapy (622) was partly offset by a reduction of the cost of co-medication (-130; 95% CI: -210 to -50). Overall, the total medical cost was 453 higher in the first year of lamotrigine therapy than in the year before the start of lamotrigine. Lamotrigine was effective in 47% of all the patients, making the resultant incremental cost-effectiveness ratio 954 per year.

DISCUSSION

Add-on therapy of lamotrigine for patients with uncontrolled epilepsy offers improved health outcomes. Lamotrigine therapy is associated with increased cost (453) and an annual incremental cost-effectiveness ratio of 954. These data, together with utility data published in the literature, support the notion that lamotrigine should be considered as an add-on therapy in for patients with refractory epilepsy.

The use of lamotrigine and other antiepileptic drugs in paediatric patients at a Malaysian hospital

OBJECTIVE

(1) To determine the effect of lamotrigine add-on therapy on the seizure frequency and cost in paediatric patients. (2) To determine the prescribing pattern of other antiepileptic drugs (AEDs).

METHOD

A retrospective study of medical records was carried out from October 2000 to June 2001 at the paediatric clinic, Hospital Pulau Pinang.

MAIN OUTCOME MEASURE

Seizure frequency, cost of drug and types of AED prescribed.

RESULTS

A total of 209 medical records were retrieved during the study period. Lamotrigine (LTG) was prescribed in 29 patients as add-on therapy. In 18 patients, there was a significant reduction in seizure frequency after the addition of LTG. Approximately 70% experienced a reduction in seizure frequency of more than 50%. Side effects of LTG were considered mild and manageable. However, drug cost after the addition of LTG increased by 103%. In the remaining 180 patients, the most common AED prescribed was sodium valproate (VPA). Only 15% of the patients received combination therapy. Mean monthly cost of monotherapy was found to be RM 24.4 while monthly cost of combination therapy was RM 45.4 (1 Euro-RM 5.00).

CONCLUSION

The majority of paediatric patients in the study are on AED monotherapy and only a small percentage was prescribed lamotrigine. The use of lamotrigine is associated with better seizure control but with an increase in drug cost.

Understanding the burden of epilepsy in Latin America: A systematic review of its prevalence and incidence

RATIONALE

Epilepsy is the most common serious neurological condition in the world, and an important cause of mortality and disability in developing countries. Because epidemiological and clinical characteristics of epilepsy vary by region, it is important to know the peculiarities of epilepsy in this area of the American continent.

METHODS

We searched MEDLINE, IMBIOMED, and LILACS (The Latin-American and Caribbean biomedical database) to identify community-based studies reporting on the prevalence and incidence of epilepsy in Latin America. Studies were included if a definition of epilepsy was given, if data were obtained through standardized questionnaires and if raw population numbers were available for data confirmation.

RESULTS

Thirty-three studies fulfilled eligibility criteria, 32 reported on prevalence and three on incidence of epilepsy. The median lifetime prevalence in all countries was 17.8 (range 6-43.2) per 1000 people, and the range for incidence was 77.7-190 per 100,000 people per year. There were no differences between rural and urban areas, by gender, age-group (children, adult, all ages), ascertainment method, or year of study.

CONCLUSIONS

Measuring the global burden of disease in Latin America requires adequate epidemiological information. This systematic review of epidemiological studies identifies higher prevalence and incidence rates of epilepsy in the general population of Latin America than in northern hemisphere countries. The remarkable heterogeneity found between and even within countries, could be explained by several factors, importantly, socioeconomic and methodological aspects.

[The clinical and economic impact of generic drugs in the treatment of epilepsy]

AIMS

The aim of this study was to determine whether the introduction of generic formulations of antiepileptic drugs (AED) would lead to an economic saving for the public health service.

DEVELOPMENT

The narrow therapeutic index, low solubility and non-linear pharmacokinetics of some AED mean that the ranges of bioequivalence that are authorised for generic formulations do not offer the same results regarding effectiveness and safety as those obtained by brand name drugs. This is why the potential saving stemming from the use of generic AED may be exceeded by the costs deriving from the consequences conditioned by their utilisation. These are the conclusions that can be drawn from the results of cost and effectiveness analyses conducted on two hypothetical cases of substituting (9 and 20%) treatments involving brand name carbamazepine (CBZ) with generic formulations. If a generic CBZ were introduced into the treatment of 9% of the patients taking this drug, the annual cost for one person with epilepsy would rise by 38.17 as compared to treating all these patients with brand name CBZ (marginal cost-effectiveness), and overall spending on health care in the country would grow by 2,748,000 (cost-benefit analysis). These figures rise sharply when 20% of treatments with brand name CBZ are replaced by generic formulations.

CONCLUSIONS

The bioequivalence ranges authorised for generic formulations may be inappropriate for generic AED. With certain AED, replacing a brand name product with a generic version of the same medication can have negative effects on the amount of health care resources that are consumed and, therefore, on the overall economic expenditure associated with epilepsy.

Cost-effectiveness of First-line Antiepileptic Drug Treatments in the Developing World: A Population-level Analysis

PURPOSE

To establish the population-level costs and cost-effectiveness of first-line antiepileptic drug (AED) treatments for reducing the treatment gap in developing countries.

METHODS

A population model was applied to nine World Health Organization (WHO) developing subregions to estimate the impact of four first-line AEDs in the primary care management of (ICD-10 defined) idiopathic epilepsy and epileptic syndromes: phenobarbitone (PB), phenytoin (PHT), carbamazepine (CBZ), and valproic acid (VPA). The efficacy of treatment was gauged in terms of improvements to both disability and recovery, subsequently adjusted for treatment coverage, response, and adherence. Total population-level treatment effects (measured in disability-adjusted life years or DALYs averted) and treatment costs (measured in international dollars; IUS dollars) were combined to form ratios of cost-effectiveness.

RESULTS

Across nine developing WHO subregions, extending AED treatment coverage to 50% of primary epilepsy cases would avert between 150 and 650 DALYs per one million population (equivalent to 13-40% of the current burden), at an annual cost per capita of IUS dollars 0.20-1.33. Older first-line AEDs (PB, PHT) were most cost-effective on account of their similar efficacy but lower acquisition cost (IUS dollars 800-2,000 for each DALY averted).

CONCLUSIONS

A significant proportion of the current burden of epilepsy in developing countries is avertable by scaling-up the routine availability of low-cost AEDs. Critical factors in the successful implementation of such a scaled-up level of service delivery, apart from renewed political support and investment, relate to appropriate training and continuity of drug supply.

Educational problems with underlying neuropsychological impairment are common in children with Benign Epilepsy of Childhood with Centrotemporal Spikes (BECTS)

INTRODUCTION

Benign Epilepsy of Childhood with Centrotemporal Spikes (BECTS) is one of the most common childhood epilepsies with a good prognosis regarding the seizure and neuropsychological outcomes. However, recent reports indicate the presence of neuropsychological problems in a significant percentage of children with BECTS. Our study was aimed to examine the educational performance and neuropsychological functions along with clinical and electrographic characteristics in a cohort of children with BECTS.

METHODS

We identified a cohort of children with BECTS by screening medical and EEG recordings of patients attending our institute. Data were collected with a standard protocol. Their educational performance was evaluated by an interview with the parents. Neuropsychological and language tests were administered to children who had educational problems. Statistical analysis was done using the chi2-test.

RESULTS

Fifty children (29 boys and 21 girls; mean age of onset of epilepsy 7.84+/-2.87 years) who met the criteria for BECTS were included in this study. Atypical seizure characteristics for BECTS were observed in 26 (52%) children. EEG showed typical centrotemporal spike and wave discharges in all children, 42% of them had a tangential dipole in the frontocentral region. An additional extra-rolandic focus in the EEG was found in seven children (14%). Educational problems were identified in 27 children (54%); 19 of them had neuropsychological or language impairment (p=0.003). We found a statistically significant correlation between the occurrence of educational problems and the absence of a tangential dipole in the EEG (p<0.001). Abnormal language function had a significant correlation with atypical seizure semiology (p=0.021).

CONCLUSION

This study shows that a significant number of children with BECTS have neuropsychological impairment and educational problems.

A review of the costs of managing childhood epilepsy

Epilepsy is a chronic treatable condition for which new diagnostic tools and several new drugs and non-pharmacological treatments are now available. The cost profile of these options is assessed here through an overview of the available literature focusing on studies of childhood epilepsy. Several methodological problems arise when interpreting the results of economic studies in epilepsy, including the variability of the study population and costs items, the reliability of the sources of cost, the limitations of the methods of data collection and the deficiencies of the study designs, with reference to the measures of treatment benefits. International comparisons are then difficult because economic results cannot be compared on account of differences in monetary issues, clinical practice patterns and healthcare system frameworks. The economic aspects of epilepsy are different in children and adults. Differences are detectable in the incidence and expression of epileptic syndromes, social and emotional impact, availability of antiepileptic drugs, hospital admissions, diagnostic tests and referral to specialists, social assistants and other healthcare professionals. In addition, children have access to medical services only with the help of a caregiver, for whom there may be lost work days or under-employment. The mean annual cost per child with epilepsy was USD 1853 for controlled epilepsy and USD 4950 for uncontrolled epilepsy in a Spanish study performed in 1998 and the annual direct costs per child with epilepsy ranged from euro 844 for patients in remission to euro 3268 for patients with drug-resistant epilepsy in an Italian study done between 1996 and 1998. The Spanish study showed that direct costs are the major source of expenditure for children with epilepsy. These studies along with a number of other cost-of-illness studies in combined populations of adults and children showed that service use and costs increase with more severe forms of illness and seizure frequency, this being more marked in adults than in children. Moderate cost differences may be expected between children (higher) and adults (lower), particularly with reference to initial investigations. Costs of epilepsy are mostly explained by hospital admissions and drugs; in particular, drug costs tend to dominate in more well controlled epilepsy, while both hospital admissions and drugs are significant costs in less well controlled epilepsy. Newly diagnosed patients can incur significant hospital and diagnostic costs. Costs for epilepsy tend to be lower for patients cared for in general practice or outpatient settings than in hospital settings. Seizure control by drugs, ketogenic diet or surgery is associated with a significant reduction in the costs of epilepsy.

Economic evaluation of levetiracetam as an add-on therapy in patients with refractory epilepsy

OBJECTIVES

This study provides the results of a cost-effectiveness analysis of levetiracetam as an adjunctive treatment for refractory epilepsy from the Canadian Ministry of Health perspective. The main objective is to estimate the expected cost-effectiveness ratio expressed as the incremental cost per seizure-free day gained when using levetiracetam. In addition, this study examines the potential savings that might result by reducing the number of surgical evaluations and surgery when using levetiracetam.

METHODS

A 1-year dose escalation decision-tree model comparing levetiracetam plus standard therapy with standard therapy alone was designed in order to combine probability, resource use and unit cost data (1999 Canadian dollars [$Can]). The short-term outcomes were derived from three phase III randomised, double-blind, placebo-controlled trials performed in 904 patients, aged 16-70 years, with at least 1 year history of epilepsy, two to four partial seizures per month, and receiving a maximum of two classic antiepileptic drugs.

RESULTS

The average gain in seizure-free days attributed to levetiracetam was 19 days per patient per year and the incremental cost-effectiveness ratio (ICER) for levetiracetam add-on in the base-case scenario was $Can80.7 per seizure-free day gained per patient per year. Moreover, when surgical investigation and surgery are considered in the model, the use of levetiracetam may be dominant, with substantial savings to the overall healthcare budget. All univariate sensitivity analyses show that the model was robust to the assumptions made.

CONCLUSIONS

The economic analysis presented in this paper suggests, given a wide range of assumptions, that the increased cost of treating patients (with refractory epilepsy) with levetiracetam may be partially offset by a reduction in other direct medical costs (from the Canadian Ministry of Health perspective), as a consequence of an increase in the number of seizure-free days. Moreover, potential cost savings may be foreseen when it is assumed that levetiracetam may reduce the number of candidates for surgical evaluation and surgery through a reduction of seizure frequency.

Epilepsy and insurance in the UK: an exploratory survey of the experiences of people with epilepsy

We investigated problems in obtaining insurance as reported by people with epilepsy who were members of a major United Kingdom patient organisation. Information was collected via questionnaires mailed to a random sample of the membership, 347 of whom replied. Overall, 62% of respondents reported experiencing a problem obtaining insurance coverage (increased premiums, restricted coverage, or outright refusal). Thirty-six percent of respondents reported having been refused one or more types of insurance on the grounds of their epilepsy. Although the low response rate to the study represents an important source of bias, extrapolation from our figures suggests a problem prevalence rate of at least 10%. Adoption of an evidence-based and standardised approach to informing assessments of risk is vital if insurance companies are to provide fair and reasonable terms for insurance coverage to their clients with epilepsy.

[The economic impact of epilepsy]

AIMS

In this study we review the economic impact involved in suffering from this disease in an attempt to determine how it affects both the individual and society, and the potential benefits deriving from its prevention and treatment.

DEVELOPMENT

The World Health Organisation and the World Bank have pointed out that 90% of the costs generated by epilepsy are produced in developing countries. Yet in most developed countries the economic impact of the disease remains partially hidden for patients by the existence of publicly funded health service. As regards spending on pharmaceutical products in Spain, the subgroup made up of the antiepileptic drugs accounted for 1.36% of the total spending throughout the year 2001. Nevertheless, the main economic consequence for most patients is the limitation they suffer in their occupational activities, which is inversely proportional to the degree of control over their seizures and considerably higher than in the general population. Moreover, in epilepsy we must not forget the costs linked to its numerous psychological and social consequences.

CONCLUSIONS

As happens in other areas of health care, the way epilepsy is attended depends to a large extent on economic factors. Further studies are therefore needed to provide us with a better understanding of the role played by economics in the field of health care.

Estimated cost of inpatient admissions and outpatient appointments for a population with epilepsy: a record linkage study

PURPOSE

This study describes the hospital costs for a population with epilepsy in 1 year (1999). The study was conducted in a defined geographic United Kingdom population of 424,000.

METHODS

A register of patients with epilepsy was constructed by using a variety of data sources that had undergone a process of record linkage. Hospital admissions were coded by using Healthcare Resource Group (HRG) and costed by using published National Health Service reference costs. A population of 3,892 people with epilepsy was recorded.

RESULTS

The cost of inpatient care for these patients with epilepsy was pound 2,537,386 ($4,135,939), an excess of pound 1,598,909 ($2,606,222) compared with the population as a whole. Of this, pound 320,182 ($521,897) was associated with a primary diagnosis of epilepsy, and pound 679,757 ($1,108,004) was associated with secondary diagnoses. Outpatient expenditure was pound 732,823 ($1,194,501).

CONCLUSIONS

This study demonstrates that people with epilepsy use excess resources and that this is not explained solely by either the direct or indirect effects of their epilepsy. These data may help in understanding of the complex issues surrounding the health economics of epilepsy.

Comprehensive Care of the Epilepsy Patient-Control, Comorbidity, and Cost

Traditionally, control of seizures in patients with epilepsy is viewed as the most important clinical outcome. Yet, current antiepileptic drugs (AEDs) do not always achieve this. Around 30-40% of patients remain uncontrolled despite pharmacological intervention. Poor tolerability of AEDs is a large part of the problem and contributes as much to the overall effectiveness of therapy as efficacy. Comorbid conditions are present in many patients, and appropriate management of these can further improve seizure control and quality of life. Patients with epilepsy often experience--among other disorders--neuropsychological effects, migraines, and psychological problems (especially anxiety and depression). Sleep disturbances are also common and have been shown to contribute to the intractability of seizures in some patients. Many anticonvulsant treatments have the potential to improve--or in some cases worsen--these concurrent conditions, and these properties should therefore be considered in the total care of the patient. Finally, the costs of uncontrolled epilepsy are measured not only in terms of direct healthcare-related costs, but also in terms of lost productivity and opportunity. The indirect costs of epilepsy are substantial and account for 70-85% of total disease-related costs. Patients with uncontrolled seizures contribute disproportionately to healthcare costs, reinforcing the need for the development of newer AEDs with improved profiles of efficacy and tolerability, but with minimal adverse effects on behavior, cognition, and sleep.

Economic evaluation of epilepsy in Kiremba (Burundi): a case-control study

PURPOSE

Epilepsy is a common disease whose prevalence across Africa is extremely variable (from 5 to 74 per thousand ). Its social and economic consequences in this continent are not well established. The objective of this study was to compare the cost of care of patients with epilepsy with that of controls in the commune of Kiremba in Burundi.

METHODS

The survey was carried out in the commune of Kiremba from March 1, 2001, to April 30, 2001. A sample of cases (patients with epilepsy) and controls was taken from the general population. The economic analysis was conducted from the viewpoint of the patient. Data collected were direct medical costs (consultations, admissions to hospital, complementary examinations, treatments) and indirect costs (evaluated from the number of days of family life disrupted).

RESULTS

In this study, 1,056 patients were included (352 patients with epilepsy and 704 controls). The total annual cost of patients with epilepsy was US dollars 11.0 against US dollars 7.3 for controls (p = 0.03). The indirect costs represented 75.8% of the total cost. For the people with epilepsy that took antiepileptic treatment (n = 18), the annual average total cost became US dollars 48.4. The number of disrupted days was 10.2 days (SD, 18.7 days) for the treated patients with epilepsy and 2.0 days (SD, 9.0 days) for the untreated ones (p < 0.001).

CONCLUSIONS

Epilepsy was responsible for an extra cost: an increased direct cost along with more disruption of family life. This extra cost remained after adjustment for use of health care and antiepileptic treatments. Various measures could be envisioned to reduce the impact of indirect costs.

Childhood epilepsy: a critical review of cost-of-illness studies

Epilepsy is an illness with multiple consequences and costs for children, families and society. There are only a few studies published on the cost of childhood epilepsy. The different methodologies used in these studies make it difficult to compare them or even to compare the cost of childhood epilepsy treatment with that of adult epilepsy. Nevertheless, studies highlight important differences in the distribution of costs associated with childhood epilepsy and epilepsy in adults. It is understandable that direct costs represent the higher percentage of the total cost associated with childhood epilepsy treatment, given the higher number of hospital admissions and investigations, as well as the complexity of therapeutic trials, while indirect costs represent the greater proportion in adult epilepsy treatment. In addition to age, the total cost associated with epilepsy also depends on other factors such as seizure frequency, the moment at which the illness cost is estimated and the local health care system. In summary, chronic illnesses not only have an influence on the physical and psychological development of children, they also impose costs on the family and society. Childhood epilepsy has greater economic costs than those generated by more prevalent, chronic illnesses.

Cost of Epilepsy in Patients Attending a Secondary‐level Hospital in India

The study objective was out to provide an estimate of cost of epilepsy in a secondary level hospital in northern India where a once a week epilepsy clinic is run. Cost data were based on existing information on costs of the hospital and market rates for drugs and investigations. Other necessary information was extracted from patient records for the year 2001. Both direct (consultation fees, cost of investigation, drugs and facility costs) and indirect (traveling and loss of productivity) were estimated. A 25% loss of productivity was assumed based on interviews with the epilepsy patients attending the clinic. There were a total of 184 patients attending the epilepsy clinic during the year 2001. The annual drug cost of epilepsy treatment using phenobarbitone was 11 US dollars. The cost of drugs was in the ratio 1:2:3:4 for phenobarbitone, phenytoin, carbamazepine and sodium valproate. The average annual cost of outpatient treatment of epilepsy was found to be 47 US dollars per patient. The annual cost incurred in emergency and inpatient management was estimated at 810.50 US dollars and 168.30 US dollars for all the patients attending the secondary hospital during the year 2001. The total annual treatment cost for patients attending the hospital was 11,470 US dollars. The annual productivity loss for the same patients was estimated at 20,475 US dollars. Applying these to the estimated 5 million epilepsy patients in India, it comes to about 0.2% of the GNP of the country. As disease cost is much lower than productivity loss, epilepsy treatment is a worthwhile investment for the society. Treating epilepsy patients at primary level using phenobarbitone will increase the treatment coverage and reduce treatment costs. Simultaneous efforts must be made to bring the epilepsy patients on mainstream so as to reduce the productivity loss.

Epilepsy surgery: patient-perceived long-term costs and benefits

PURPOSE

The goal of this study was to assess the patient-perceived costs and benefits associated with the longer-term outcomes of epilepsy surgery in patients who underwent anterior temporal lobectomy or selective amygdalohippocampectomy.

METHODS

Surgery patients who were assessed in 1997 were reassessed in 2003. Demographic, clinical, and psychosocial details were collected using a validated self-completion questionnaire. Data were collected from 67 patients who had undergone surgery.

RESULTS

Forty-five percent were seizure-free. There were significant differences (P<0.001) between the seizure-free (SF) and continuous seizure (CS) groups with respect to anxiety, depression, impact of epilepsy, self-esteem, mastery, stigma, affect balance, self-reported health, and quality of life. More SF patients were also employed and driving (P<0.001). Despite these differences there were no differences for regret over surgery but there were differences for satisfaction and success ratings.

CONCLUSIONS

Patients who were not SF, in the longer term, had little regret undergoing surgery but were less likely to be satisfied and had a poorer psychosocial profile.

Direct Cost of Medical Management of Epilepsy among Adults in Italy: A Prospective Cost-of-Illness Study (EPICOS)

PURPOSE

To investigate the costs of epilepsy from a nationwide survey comparing adult patients included in different prognostic categories.

METHODS

A 12-month prospective observational study was conducted in 15 epilepsy centers from Northern, Central, and Southern Italy. The study population included a random sample of individuals aged 18 years and older with newly diagnosed (ND) epilepsy, seizure remission (R), occasional seizures (OS), active non-drug-resistant (NDR) seizures, drug-resistant (DR) seizures, or surgical candidates (SC). Estimates of the direct costs of care of epilepsy were based on the use of diagnostic examinations, laboratory tests, specialist consultations, hospital admissions, day-hospital days, and drugs, taking the Italian National Health Service perspective.

RESULTS

The sample included 631 patients (ND 62, R 158, OS 155, NDR 114, DR 128, and SC 14). The SC group had the highest total cost per patient (3,619 euros) followed by DR (2,190 euros), ND (976 euros), NDR (894 euros), OS (830 euros), and R (561 euros). For each epilepsy group, the main components of the total cost were drugs and hospital admissions. Drug costs increased from the R group to the DR group. The new antiepileptic drugs (AEDs) were the largest part of the cost of treatment.

CONCLUSIONS

The costs of epilepsy in referral patients vary significantly according to the time course of the disease and the response to treatment. Hospital admissions and drugs are the major sources of expenditure.

Some problems and pitfalls in developing countries

In developed countries with well-structured health care and reimbursement systems, epilepsy care is evidence based. By contrast, in developing countries, patients with epilepsy encounter several significant barriers to adequate treatment and are more often managed according to local ethnic, racial, religious, economic, educational, and cultural diversities. Cost is one issue that clearly determines antiepileptic drug (AED) selection, and it is reasonable to recommend one of the traditional, and cheaper, AEDs as first-line therapy. However, the appropriate choice of drug in an individual patient is a balance of efficacy, tolerability, and cost and should be tailored to individual affordability.

Annual direct medical cost and contributing factors to total cost of epilepsy in Oman

OBJECTIVES

To describe the pharmaceutical use, health care resource utilisation patterns, and annual direct medical cost of epilepsy as well as determining the impact of various demographic and clinical characteristics on total costs of epilepsy in Oman.

METHODS

Medical and pharmacy data were collected for 6 months on all patients aged > or =13 years attending the Sultan Qaboos University Hospital. Unit pharmacy and medical costs were retrieved for each patient, and multiple linear regression was utilised to analyse the impact of various demographic and clinical characteristics on total cost.

RESULTS

A total of 486 patients were seen over the study period. Annual direct medical costs of epilepsy amounted to 1,426 US dollars. In-patient care, the antiepileptic drug (AED) lamotrigine and specialist visits, respectively, were the first, second and third most significant predictors of total cost. Age was associated positively, and was the most significant predictor of total costs among demographic and clinical parameters.

CONCLUSIONS

This analysis, the first economic study of epilepsy in Oman, could assist in health care allocation of scarce resources and in pharmacoeconomic analysis of AEDs. Besides in-patient admission, our findings demonstrate that the newer drugs are significant predictors of total cost, and hence any incremental benefits derived from them must be rigorously assessed for their cost-effectiveness.

Cost-utility analysis of vagus nerve stimulators for adults with medically refractory epilepsy

INTRODUCTION

The cost-utility of vagus nerve stimulator (VNS) devices for medically refractory epilepsy has yet to be estimated.

METHODS

Using a meta-analysis of randomised controlled trials of VNS, we estimate that six people require implantation in order for one person to experience a 50% reduction in seizure frequency. Costs averted from improved epilepsy control were ascertained from published literature. Values for health states were obtained from a series of 42 seizure clinic attenders using time trade-off techniques and the EQ-5D health status instrument. The cost per quality adjusted life year gained was estimated and the values obtained were tested in a sensitivity analysis.

RESULTS

Improved epilepsy control averted, on average, 745 pounds sterling health care costs per annum. People with epilepsy had great difficulty performing the time trade-off experiment, but those who managed to complete the task valued a 50% reduction in their own seizure frequency at 0.285 units. For a programme of six implants, the baseline model estimated the cost per quality adjusted life year gained at 28,849 pounds sterling. The most favourable estimate was equal to 4785 pounds sterling per quality adjusted life year gained, assuming that the number needed to treat was similar to published series in which one response was obtained for every three implants. The least favourable estimate was equal to 63,000 pounds sterling per quality adjusted life year gained, when EQ-5D utility values were used. The cost per quality adjusted life year gained was not sensitive to changes in length of stay, nor complication rates, but was significantly influenced by cost of device and device battery life expectancy.

CONCLUSION

There is not a strong economic argument against a programme of VNS implantation, although care should be taken to try and identify and treat those most likely to benefit.

The costs of epilepsy in three different populations of patients with epilepsy

The purpose of this study was to estimate the costs of care in three different populations of patients with epilepsy (general practices (GP), University Hospital (UH), and Epilepsy Center (EC)), and to analyse the distribution of costs by type of services for each patient group. A cost diary was developed to obtain prospective information on epilepsy-attributable service use over a period of 3 months. Similar information over the previous 3 months was obtained from a cost questionnaire. In addition, a quality of life inventory (QOLIE-31) was used. Standard cost lists were applied for the valuation of the direct cost items. A sensitivity analysis was performed for certain cost items for which no reliable data were available. One hundred and sixteen patients with established epilepsy were included, and the mean costs per patient per month (in Euros) ranged from 52.08 to 357.63. Patients from GP appeared to have lower direct costs, spent less time in seeking or undergoing a treatment, and reported lower seizure frequencies and less severe seizure types than the patients from the other patient groups. Patients from the EC reported the highest productivity changes and unemployment rates and also had the lowest scores on the QOLIE-31. The cost items anti-epileptic drugs, hospital services, unpaid care, and transportation accounted for the majority of the total direct costs.

ILAE Commission of European Affairs Subcommission on European Guidelines 1998-2001: The provision of epilepsy care across Europe

PURPOSE

To assess the needs and resources available in the provision of basic epilepsy care across Europe.

METHODS

A mailed questionnaire was used, the European Epilepsy Services inventory (EESI). The EESI was distributed to all 36 European chapters of the International League Against Epilepsy (ILAE), and answers were obtained from 32, a response rate of 89%. For the purpose of studying trends across Europe, the chapters were divided into a Western, an Eastern, a Central, and a Southern group.

RESULTS

The survey results showed that there was a wide range in the number of physicians and specialists involved in epilepsy care across Europe, with a trend toward higher numbers of neurologists, pediatricians, and pediatric neurologists in Eastern Europe. Many different specialties were involved in epilepsy care, and many chapters reported differences in the provision of care across their countries, with less possibility for patients to see a specialist in the least provided areas, where most epilepsy patients were cared for by general practitioners and internists. Problems with high costs of the newer antiepileptic drugs were most pronounced in Eastern Europe. Problems with lack of comprehensive care and of epilepsy specialists, with stigma and social problems, and with insufficient professional education and knowledge about epilepsy were reported all across Europe.

CONCLUSIONS

Knowledge about differences in the pattern of provision of epilepsy care and about the main problems encountered by the European ILAE chapters is of importance in the continuing efforts to improve management of epilepsy all over Europe.

[Antiepileptic treatment nearly six times more expensive since 1990]

There is a six-fold increase in the costs for antiepileptic drug prescriptions in Sweden from 1990 to 2000. This is mainly caused by a gradual increase in the prescribing of new and more expensive drugs, since the total use of antiepileptic drugs, expressed as defined daily doses per 1,000 inhabitants, is almost unchanged during the same time period. A marked variation in the prescribing of new antiepileptic drugs between different counties in Sweden, suggests that the role of the new compounds is still unclear. The cost effectiveness of new antiepileptic drugs in relation to the older drugs requires further evaluation.

The cost effectiveness of two new antiepileptic therapies in the absence of direct comparative data: a first approximation

BACKGROUND

A number of new antiepileptic agents have been introduced within a short period of time. Direct comparisons are not available, and information about the balance between costs and effects for these new therapies is lacking.

OBJECTIVE

To introduce a first approximation of the cost effectiveness of the new therapeutic agents (topiramate and lamotrigine) for epilepsy that have been assessed in clinical trials against placebo.

METHODS

Without head to head comparative data no formal methods are available to assess the relative cost effectiveness of two products; therefore, a Bayesian approach was developed. The approach starts with the 'proportionality assumption' saying that the differences in healthcare expenditure (less the direct cost of therapy) are directly proportional to the differences in effectiveness. Given this assumption, a therapy that is x times as expensive as an alternative therapy has an equivalent cost-effectiveness profile if the acquisition cost is x times as high. Moreover, simple formulas can be derived to calculate the probabilities that a therapy is dominant (more effective and less expensive) and that it is weakly dominant (more effective and a better cost-effectiveness profile). The approach is applied to data from published fixed dosage, parallel-design studies comparing both topiramate and lamotrigine with placebo.

RESULTS

Assuming that the 'proportionality assumption' holds for the medical treatment of epilepsy, and disregarding uncertainties, it is estimated that topiramate may be priced more than 2.2 times its current acquisition cost and still be more cost effective than lamotrigine. Taking uncertainties into account, it is estimated that lamotrigine 500 mg/day is dominated by topiramate 200 mg/day with a probability of 0.875 and by topiramate 400 mg/day with a probability of 0.986.

CONCLUSIONS

A simple method can be applied to assess the relative cost effectiveness of two therapies in the absence of direct comparative data. Applying this method to compare topiramate and lamotrigine leads to a strong preference for topiramate. However, to be able to draw this conclusion, some heroic assumptions need to be made. As such the method as developed here only reflects a first approximation. It needs to be used with care and is not intended to replace good comparative research.

Pharmacological and therapeutic properties of valproate: a summary after 35 years of clinical experience

Thirty-five years since its introduction into clinical use, valproate (valproic acid) has become the most widely prescribed antiepileptic drug (AED) worldwide. Its pharmacological effects involve a variety of mechanisms, including increased gamma-aminobutyric acid (GABA)-ergic transmission, reduced release and/or effects of excitatory amino acids, blockade of voltage-gated sodium channels and modulation of dopaminergic and serotoninergic transmission. Valproate is available in different dosage forms for parenteral and oral use. All available oral formulations are almost completely bioavailable, but they differ in dissolution characteristics and absorption rates. In particular, sustained-release formulations are available that minimise fluctuations in serum drug concentrations during a dosing interval and can therefore be given once or twice daily. Valproic acid is about 90% bound to plasma proteins, and the degree of binding decreases with increasing drug concentration within the clinically occurring range. Valproic acid is extensively metabolised by microsomal glucuronide conjugation, mitochondrial beta-oxidation and cytochrome P450-dependent omega-, (omega-1)- and (omega-2)-oxidation. The elimination half-life is in the order of 9 to 18 hours, but shorter values (5 to 12 hours) are observed in patients comedicated with enzyme-inducing agents such as phenytoin, carbamazepine and barbiturates. Valproate itself is devoid of enzyme-inducing properties, but it has the potential of inhibiting drug metabolism and can increase by this mechanism the plasma concentrations of certain coadministered drugs, including phenobarbital (phenobarbitone), lamotrigine and zidovudine. Valproate is a broad spectrum AED, being effective against all seizure types. In patients with newly diagnosed partial seizures (with or without secondary generalisation) and/or primarily generalised tonic-clonic seizures, the efficacy of valproate is comparable to that of phenytoin, carbamazepine and phenobarbital, although in most comparative trials the tolerability of phenobarbital was inferior to that of the other drugs. Valproate is generally regarded as a first-choice agent for most forms of idiopathic and symptomatic generalised epilepsies. Many of these syndromes are associated with multiple seizure types, including tonic-clonic, myoclonic and absence seizures, and prescription of a broad-spectrum drug such as valproate has clear advantages in this situation. A number of reports have also suggested that intravenous valproate could be of value in the treatment of convulsive and nonconvulsive status epilepticus, but further studies are required to establish in more detail the role of the drug in this indication. The most commonly reported adverse effects of valproate include gastrointestinal disturbances, tremor and bodyweight gain. Other notable adverse effects include encephalopathy symptoms (at times associated with hyperammonaemia), platelet disorders, pancreatitis, liver toxicity (with an overall incidence of 1 in 20,000, but a frequency as high as 1 in 600 or 1 in 800 in high-risk groups such as infants below 2 years of age receiving anticonvulsant polytherapy) and teratogenicity, including a 1 to 3% risk of neural tube defects. Some studies have also suggested that menstrual disorders and certain clinical, ultrasound or endocrine manifestations of reproductive system disorders, including polycystic ovary syndrome, may be more common in women treated with valproate than in those treated with other AEDs. However, the precise relevance of the latter findings remains to be evaluated in large, prospective, randomised studies.

Launching a research initiative: the Canadian Pediatric Epilepsy Network (CPEN)

The Canadian Pediatric Epilepsy Network is a network of scientists and health care professionals in partnership with organizations which provide education and support to children with epilepsy. The objective of the network is to gain a better understanding of childhood epilepsy through collaborative research conducted with doctors, psychologists, nurses, social workers, educators and scientists across Canada. The network was launched at a meeting in Ottawa in the spring of 2000 where several oral presentations addressed the issues of the fundamental questions of epilepsy, the economic impact and the neuropsychology of childhood epilepsy. The intent was to provoke discussion on future areas of research for the network.

The global burden of epilepsy

We briefly describe the Global Burden of Diseases (GBD) study, its goals, and some of its outcomes as related to neurologic and psychiatric disorders. The summary measure of population health DALYs (Disability Adjusted Life Years) are described, as well as the implications for neuropsychiatric disorders of changing health indicators and the move from mortality toward disability indicators. The pressing need for new measures for health is answered by the new WHO Classification of Functioning Disability and Health, ICF, and a brief summary of its basic principles is provided. Although a better understanding of the physical, social, and economic burden of epilepsy has moved this disorder higher on the world's agenda, epilepsy still has problems to be recognized as a public health priority. The implications of a shift toward considering the disability of epilepsy, as outlined in the the WHO World Health Report 2001, are important. The burden of epilepsy is high and, for the year 2000, accounts for approximately 0.5% of the whole burden of diseases in the world.

Help-seeking patterns for children with epilepsy in rural India: implications for service delivery

PURPOSE

Most people in the world with epilepsy are untreated with antiepileptic drugs (AEDs). In some developing countries, this is because treatment facilities are unavailable or difficult to access. It has even been suggested that indigenous health systems threaten the prospect of the global control of epilepsy with AEDs. We have investigated patterns and costs of help seeking for children with epilepsy in a region of rural India where only 12% of children with epilepsy were in treatment. Our objective was to find out (a) whom families had consulted; (b) if nonconsulting families differed in demographic or child medical factors; (c) if indigenous treatment was taken, exclusive of allopathic treatment; and (d) the direct and indirect cost of various providers.

METHODS

We conducted a cross-sectional interview study in a community-based program for childhood epilepsy in rural West Bengal, India. We interviewed parents of 85 children aged 2 to 18 years with untreated epilepsy who had entered a clinical trial of AEDs during 1995 through 1996.

RESULTS

Eighty percent of families had sought some help in the past: 62% with an allopathic practitioner, 44% with traditional practitioners. Primary health centres (PHCs) and quacks were not popular. Twenty-four percent of families never sought help of any kind, and this was unassociated with sex, income, maternal literacy, or medical variables. There was evidence of both exclusivity and pluralism: 42% of families first consulting allopathic practitioners also visited traditional practitioners, whereas 30% of families first consulting traditional practitioners also went to allopathic practitioners. One visit to a physician cost a median of 9-13% of monthly income and 5-12 person-hours; the cost of visiting indigenous providers was negligible.

CONCLUSIONS

Most families sought some form of help and were motivated to spend large amounts of money and time for allopathic treatments from qualified practitioners. The typical cost of allopathic treatment was unsustainable in the long term. Medical pluralism is common and does not adversely influence use of allopathic treatment. The phenomenon of nonconsulting merits further study. Traditional practitioners play a complementary role and might become involved in community treatment programs. Low-cost, local treatment is essential to the public health control of epilepsy.

Economic evaluation of epilepsy treatment: a review of the literature

This article provides an overview of methods used and findings from economic analyses in epilepsy. Cost-effectiveness studies have evaluated different drugs for monotherapy and add-on therapy, and compared alternative treatment modalities for refractory epilepsy. The methodological characteristics of these studies are examined, and their results are compared and interpreted. Health outcome measures are defined and data sources described. Methods for assessing the direct and indirect costs, and/or cost savings, with a treatment's use, are explored. Directions for future research are identified and discussed.

The economic cost of epilepsy: a review of the literature

Economic concerns are increasingly important in health system design, provider payment, and research funding decisions. Cost estimates are needed to provide insight into where the potential opportunities for cost-savings lie and to lay the groundwork for research to determine how to treat the disorder more effectively. The methods used by economists to estimate the direct and indirect costs of epilepsy are reviewed and results from studies in different countries are discussed. General patterns across patients with different types of conditions are reported. Gaps in the literature are identified and future research needs are assessed.

Cost-effectiveness of epilepsy therapy: how should treatment effects be measured?

Economic evaluations aim to inform policy makers about the cost-effectiveness of different therapies so that limited health care resources may be allocated efficiently. For such evaluations, the effects of therapy must be captured by measures that are reliable, valid, and clinically meaningful. Mortality and changes in disease activity (e.g., seizure freedom, reduction in seizure frequency) may be reliable and valid, but their clinical meaning is not always apparent. Changes in widely used "quality-of-life" measures can quantify therapeutic effects, but the value of such changes to patients is not necessarily clear. This article reviews conceptual and methodological issues involved in determining the value of health effects in the context of economic evaluations of epilepsy therapies. Techniques for eliciting preferences for health effects are reviewed. The limited information on preferences for epilepsy-related health states is described. Directions for further research are suggested.