Money matters in epilepsy.
Cost of epilepsy care has escalated many folds in the recent past. The high cost of newer anti epileptic drugs, cost of elaborate presurgical evaluation and surgery account for a large component of direct medical cost. Indirect cost to the society, through lost productivity or premature death, is many times more than the direct cost. The newer drugs have an advantage over the conventional drugs in terms of tolerability, safety and ease of administration. The benefits in terms of better control of seizures and improvement in quality of life offered by these newer strategies in treatment of epilepsy need to be considered along with the increase in cost. Careful economic evaluation is essential to assess ultimate utility of these interventions in the management of epilepsy at large. Unfortunately, there is little data on this aspect for the physician to apply in his practice. The general principles of economic appraisal of epilepsy and some of the key works in this field are discussed in this paper. The increase in cost due to newer anti epileptic drugs in the treatment of unselected population of patients (mild and severe epilepsy) may not be adequately justified by gains in seizure control. On the other hand newer drugs may have a clear superiority in selected situations such as intractable seizures. The high initial cost of presurgical evaluation and epilepsy surgery may be offset by gains in increased number of quality adjusted life years.
Epilepsy is the commonest neurological disorder in the world. There have been remarkable advancements in clinical epileptology in the recent past. Many new anti epileptic drugs (AED) have been marketed in this decade. Epilepsy surgery has established itself as a safe and effective option for intractable epilepsy.
Cognitive, psychosocial and gender issues have gained more attention, with the result that quality of life has become the central focus of epilepsy care. Progress in epilepsy care has inevitably escalated its cost as well. Recently, there had been much debate on the economic aspects of newer modalities of treatment of epilepsy., The International League Against Epilepsy (ILAE) Commission on economic aspects, in a recent report, has highlighted the need for thorough appraisal of the economic aspects of epilepsy. Thorough economic appraisal of newer strategies in epilepsy care, be it newer AEDs or epilepsy surgery, would enable the clinician to make judicious decisions in patient care. Most clinicians have little exposure to health economics, as it is a relatively new discipline in health sciences. In future, as third party payment of medical bills becomes more prevalent, there will be greater pressure for cost containment without compromising on quality of services. In this article, the broad principles of estimating the cost of epilepsy and standard techniques of making economic evaluation of treatment protocols are reviewed.
In socioeconomic evaluation, costs are the resources expended to obtain a desired state of health. All resource expenditures (medical and non-medical services) incurred for the prevention, diagnosis, treatment and rehabilitation of a particular disease are included under cost [Table I]. Traditionally, resource expenditure is estimated under the direct and indirect cost. A third component of intangible cost comprising of the money equivalents for the social stigma, psychological stress and pain is also computed in some cases [Table II].
Direct cost : Direct cost can be further divided into medical costs related to the prevention, diagnosis, treatment and rehabilitation of epilepsy and nonmedical costs related to travel expenditure etc. Most of the out of pocket expenses for the patients and their families come under this category. However, the actual cost of these services is frequently much more than what a patient pays. In many instances, government or other agencies may be subsidising this component; e.g. in a government hospital, the services of the neurologists and other specialists may be provided free, and the charges for video EEG or MRI may be only the cost of consumables. Many institutions also provide some cross subsidy by which they reduce the charges for poor patients by compensating it from more well off patients. Hence, the final bill charged to the patient may be quite different from the actual costs. The cost of services may be different in different parts of the country. The cost of infrastructure in a big city may be more than that for the same in a more modest setting. These factors also should be considered while computing the cost of epilepsy care. The direct cost of epilepsy is gathered in one of the three methods viz. (1) self reported treatment data from providers or patients, (2) medical charts or billing data obtained from the provider or patient and (3) hypothetical model based on disease characteristics.
Indirect cost : Indirect cost commonly has three components (1) employment related - the lost earnings associated with reduced output when people withdraw from work due to morbidity or premature mortality (2) productivity related - the reduced earnings from absence or reduced productivity due to morbidity for those who continue to work despite the illness and (3) household related the lost value of household production when people alter the time they devote to such work because of epilepsy. Calculation of indirect cost involves in-depth examination of the impact of the illness on the socioeconomic life of the patients and their families.
Intangible cost : This aspect of epilepsy care has not yet been adequately examined. The social stigma, pain and suffering that an individual suffers because of epilepsy constitutes intangible costs. In some studies they are expressed in unit terms or scales and in some studies an economic equivalent of this loss is expressed.
Consequences or benefits are the result of using a medical service or in economic terms, the outcome of using a particular resource. With regard to epilepsy, the positive consequences would include control of seizures, years of increased productivity and probably years of life saved (by avoiding death due to accidents) and improvement in social life. The negative consequences would include adverse effect of the drugs or the investigations carried out, time expended in making repeated visits to clinic and pharmacies [Table III].
Economic evaluation can be performed from different perspective or viewpoints. Patient's perspective emphasizes the out of pocket expenditure to the patient and his family. The cost borne by the provider or society at large are less important. Quality of life, time lost to work etc. are also important from the patient's perspective. Provider's perspective evaluates costs from the service provider's (such as hospital) viewpoint. Third party payer's perspective examines cost evaluation from the insurance company or employer's view point. Societal perspective examines the entire social and economic effect of the new treatment (e.g. epilepsy surgery) on all segments of the society. Such studies would examine the lifetime medical and surgical cost and consequences. Costs related to a wide array of services such as institutional care and home services need to be included in addition to hospital care, outpatient care etc. Perspective is a key factor in defining the research question and evaluating the cost and consequence of any new program for epilepsy. The most comprehensive study examines the cost and benefits from the societal perspective.
Cost of illness studies (COI)
This is a form of evaluation which computes the current economic impact of a disease including the costs and consequences of treating the disease. No comparison of treatment modalities is made. Traditionally there are two methods of estimating the cost of an illness. The commonly used approach is the human capital method that divides cost into direct and indirect components. An alternate approach to estimate the cost of illness is the willingness to pay method. This approach defines the cost of an illness in terms of what people would be willing to pay for a hypothetical permanent cure for the disease. The former approach is more frequently used. Most of the COI studies on epilepsy have been based on prevalence based estimates.,,, Such studies do not express the variation in the cost of management due to changes in natural history of epilepsy. Longitudinal studies are ideal for estimating the cost of epilepsy over a period of time. Two such studies have been published recently.,
The first comprehensive study on cost of epilepsy in USA was carried out in 1975. That study estimated the national cost of epilepsy at $3.6 billion for 2.1 million cases. On a per patient basis, the 1975 Figureure represents US $7440 in 1995, $1150 (15%) for direct treatment-related costs and $6290 (85%) for indirect employment-related costs. Begley et al estimated the cost of epilepsy based on its natural history. They identified six prognostic groups of epilepsy. Based on epidemiological data and these models, they estimated the lifetime cost of epilepsy for a cohort of persons diagnosed in 1990 in United States. The total lifetime cost in 1990 for all persons with onset of epilepsy in 1990 was estimated at $3.0 billion (direct cost accounting for 62%). The cost per patient ranged from $4272 for persons with remission after initial diagnosis and treatment to $138,602 for persons with intractable seizures.
An exhaustive cost of illness study on epilepsy was carried out in UK. This is based on data from National Epilepsy Society and National General Practice Study Group for Epilepsy. A longitudinal cost profile of epilepsy was calculated, with an average initial direct cost of £ 611 (US$ 917) per patient per annum which decreased after eight years of follow up to £ 169 (US$ 254) per patient per annum. The cost of newly diagnosed epilepsy in the first year of diagnosis in the UK was £ 18 million (US$ 27 million). The total annual cost of established epilepsy in the UK was estimated to be £ 1930 million (US$ 2895 million), over 69% of which was due to indirect costs (unemployment and excess mortality). The cost of active epilepsy per patient was approximately £ 4167 (US$ 6251), and of inactive epilepsy £ 1630 (US$ 2445) per patient per annum. Recently, another study had been carried out in UK based on the prevalence of epilepsy. The per annum per patient direct cost of epilepsy was £ 1568. The largest single element of cost (58%) to the health service was the cost of inpatient episodes followed by drug cost (23%). There are well-conducted 'cost of illness studies' from Switzerland, Australia and other western countries [Table III].
These studies indicate that epilepsy is an enormous economic burden to the society and the major component of the cost is the indirect cost constituted by lost productivity. With effective treatment, 70 - 80% of patients can go in for remission and can be effectively rehabilitated with positive economic gain.
Special problems in evaluating cost of epilepsy
Several methodological issues that influence the economic appraisal of epilepsy should be kept in mind while interpreting data on cost of epilepsy studies. It is important to ensure that all major components of cost are included in a given study. The definition of epilepsy also assumes importance when the cost is evaluated from the societal perspective. The commonly used definition of two or more unprovoked seizures has many limitations. Considerable cost may be involved in the evaluation of single seizures which would not be included if we follow this definition.
Epilepsy is a collection of syndromes that differ widely in terms of severity. The cost of mild epilepsy with rare seizures that do not interfere with normal life is quite different from severe epilepsy with very frequent seizures and considerable morbidity. Hospital based studies are likely to reflect the client characteristics and may accordingly bias the data. There may be other co morbidities such as mental retardation or motor disability that may inflate the cost unless suitable adjustments are done. It is also important to differentiate between prevalence based studies from longitudinal studies.
General tools of economic evaluation
The value of a procedure, e.g. epilepsy surgery is equal to the sum of all costs subtracted from all consequences discounted over time at a particular discount rate. There are four commonly used approaches of cost and benefits evaluations.
Cost Benefit Analysis (CBA) : This is the most exhaustive approach in which real cost and consequences are expressed in monetary terms. In this regard, many of the resources and consequences have to be given somewhat arbitrary monetary value. For example, the anxiety that one may lose memory following the surgery is a cost and the peace of mind that seizures will not occur is a benefit which are difficult to translate into monetary units. By using monetary values on both sides of the economic appraisal equation, it is possible to estimate the net gain to the society from a particular treatment. In principle this is an excellent tool to make comparisons between different treatment protocols for the disorder and different disorders altogether. However, the monetary value assigned to many benefits is arbitrary to a large extent and may not be comparable.
Cost Effectiveness Analysis (CEA) : In this approach, the benefits are not converted into monetary units but are evaluated as such. This approach is frequently adopted to compare different treatment protocols that apparently achieve the same outcome; e.g. the costs of medical and surgical treatment can be compared against the outcome of seizure frequency, measured as the number of seizures in unit period.
Cost Utility Analysis (CUA) is another approach that measures costs in monetary terms, but measures consequences in terms of their quality or utility. In CUA no attempt is made to measure health outcomes in monetary terms. Rather, CUA employs a common non-monetary tool to measure those consequences that are not amenable to economic expression. One of the recommended tools to measure the outcome is quality adjusted life years (QALY). Disability Adjusted Life Years (DALY) is another outcome measure that can be used instead of QALY. However, utility measures have a number of disadvantages including the bias against the elderly, the impossibility of generalizing quality of life across or within patient groups.
Cost Minimization Analysis (CMA) assumes that the outcome of two treatment options are the same and a direct comparison of costs for two alternate treatment protocols can be made. For example, if the remission rates of different AEDs are same, how do we minimize the cost by choosing the AEDs.
Pharmaco-economic evaluation of epilepsy
The increase in the cost of epilepsy care due to the use of newer AEDs has been the focus of interest recently. It is estimated to be approximately US$ 500 million a year in United States. Certain methodological issues need to be kept in mind while interpreting such data; e.g. the cost of a newer AEDs (acquisition cost) may be many fold more than conventional AEDs. However the overall cost of treating epilepsy with such drugs could be less because of savings from fewer hospital visits for seizures, or management of adverse drug reactions or increased productivity. Similarly, the one-time cost of presurgical evaluation and epilepsy surgery is many times more than that of medical treatment, but the life time cost would be less for patients who achieve complete remission by surgery.
Comparison of newer AEDs against conventional AEDs
Comparative studies of monotherapy have been published for lamotrigine,, and vigabatrin as compared to carbamazepine., A cost minimization study was carried out by Shakespeare and Simeon in which carbamazepine and lamotrigine were compared as monotherapy for partial or generalized epilepsy. They observed that cost of therapy with carbamazepine was about one third of lamotrigine (£ 179 vs. £ 522) even after the costs associated with the management of adverse events and therapeutic switching were considered. Markowitz et al have used another model to examine the cost effectiveness of lamotrigine as an add on therapy for epilepsy. In this model, they estimated the cost of treating patients with intractable epilepsy with conventional AED and the cost of presurgical evaluation and surgery as the base data. The difference in cost due to introduction of lamotrigine in the ensuing ten years was projected. The results showed that in the first year the lamotrigine regime costs an additional US$ 83.9 per seizure free day, and US$ 16.3 per seizure free day gained in the 3rd to 10th year. In the second year lamotrigine costs less because fewer persons from the lamotrigine group underwent presurgical evaluation and surgery. Another recent study had examined the lifetime cost utility of lamotrigine as an add on therapy. They have observed that adjunctive lamotrigine would cost approximately US$ 41,000 per unit increase in quality adjusted life year.
The cost of medical treatment of epilepsy with Vigabatrin (VGB) was compared with the cost of evaluation and surgery for epilepsy in 52 patients with intractable epilepsy. In this study, the direct costs associated with treatment with the conventional AED, VGB, epilepsy surgery evaluation (ESE) and epilepsy surgery were analyzed. Sixty percent of the 52 patients obtained a reduction in seizure frequency of 50% or more with VGB. Of the twenty-one operated patients, 57% became seizure free. Corresponding [Figures] for VGB responders who did not go through ESE and VGB non-responders who were not operated were 6% and 0% respectively. The mean yearly costs (expressed as 1991 prices) of epilepsy-related health care including AED treatment was US$ 1594, the year before starting VGB therapy, and US$ 2959 in the first year of VGB treatment including a mean yearly cost of VGB of US$ 1572. The mean total cost for ESE and surgery was US$ 46 778 (N = 21), while the mean cost of ESE in patients evaluated but not accepted for surgery (N = 14) was US $24 054. Considering the costs for ESE and surgery in the whole patient series, the mean total cost of rendering one patient seizure free with surgery was US $110000. Surgery is the most effective treatment option in selected cases of severe partial epilepsy. If its costs are distributed over the patient's expected lifetime, the yearly cost is comparable to the present yearly cost of medication with VGB. They opined that, since many patients achieve satisfactory seizure control with VGB, and considering the risks of surgery, it is a rational policy to let patients try this drug (or another of the new generation of AED) before entering ESE.
Acquisition cost may not reflect the over all cost.
Fosphenytoin is a new AED which can be administered intravenously or intramuscularly for status epilepticus. This drug is about fifteen times more expensive than phenytoin, but was shown to have better efficacy and less adverse effects in controlled clinical trials. Two recent studies,, have shown that the outcome cost (acquisition cost plus the cost of treating adverse drug reactions) is less for fosphenytoin (US$ 156.68) than phenytoin (US$ 543.47), although the former is fifteen times more expensive (US$ 90.00 vs. US$ 6.7).
Economic aspects of epilepsy: scenario in developing countries.
Ninety per cent of the world's 40 million people with epilepsy live in developing countries. The vast majority of them are not on regular treatment. These countries have meager facilities for advanced care for epilepsy. The capital investment in epilepsy care would involve import of a number of sophisticated equipments, and their spares, as well as training of personnel to handle these equipments properly. There is fierce competition for resources from several corners and its allocation is often a political decision. Quantification of the benefits of treating epilepsy also has problems in such countries. Unemployment among the healthy population, the traditional social underexpectations from sick people, and the impact of joint families all need to be taken into consideration. Direct conversion of local currency to equivalent US dollars would also be misleading as the purchasing power and monetary value of local currency may not be adequately reflected in it. Interaction with anticysticercal drugs, anti malarial and anti tubercular drugs that are frequently prescribed for people residing in tropical countries add another dimension to this problem. A recent study from Latin America has highlighted the need for detailed studies on economic aspects of epilepsy in developing countries Chandra has drawn attention to some of the difficulties in estimating the cost of epilepsy in his study from Indonesia.
Cost of epilepsy care in India.
There is no published report on cost of epilepsy from India. In a previous study, we had examined the various services that are utilized in the care for epilepsy in Kerala State. This study, carried out at a tertiary referral center for epilepsy, indicated that primary care services are underutilized by people with epilepsy. The mean delay in diagnosis of the condition is about nine months. A study from another tertiary referral center for epilepsy in North India has suggested that the cost of epilepsy care can be reduced
and the quality of care improved by proper clinical evaluation and education of general physician. Another recent study had shown that the frequency of polytherapy with its associated higher cost can be reduced by intervention from a tertiary referral center. A multicenter study involving one center each from eight states of India was carried out recently. This is the first large scale study that has addressed the medical service utilization by patients with epilepsy. It had also examined some of the direct cost of epilepsy care in India. Patients included all age groups (mean age 23 years). Half of them had localization related epilepsy. The mean delay in diagnosis of the condition was 1.5+4 years. The average number of hospital visits was three per year (range 1-30). The median of hospitalization because of epilepsy was one per year (range 1-18). About six per cent of them were never on any AED. Polytherapy was reduced from 48% to 22% patients after referral to an advanced epilepsy center. Nearly three quarter of them (70.2%) have had at least one EEG, one third (36.1%) had one or more CT scan and only 8.5% of them had one MRI scan. The direct cost of treatment was over Rs. 5000/- [Table IV].
The mean loss of workdays was about 58 days. The indirect cost related to loss of work may be to the tune of Rs. 6000/-. The out of pocket expenditure for anterior temporal lobectomy for intractable temporal lobe epilepsy in Kerala is approximately Rs. 46700/-.
These studies have brought out some interesting aspects of pharmaco-economics and selection of cases. Newer drugs and more expensive AEDs like lamotrigine, if administered without any selection criteria, would increase the cost of treatment many folds over treatment with conventional drugs. However, these drugs may have a clear economic advantage in the case of intractable epilepsy. Similarly, the savings in terms of fewer hospital visits or admission, fewer adverse drug reactions that need intervention and better quality of life may overcome the higher acquisition cost of some of the newer drugs or surgical treatment. However, the cost of epilepsy care from the societal perspective would increase many folds if the same treatment and investigations are administered to all patients. Economic evaluation of epilepsy care is a relatively newer branch. Scientists from the field of clinical epileptology, health economics and health administrators need to work together to appraise the subject satisfactorily. Further, economic evaluation of treatment of epilepsy and its consequences in our settings would enable the physicians to improve evidence-based practice as we enter the next millenium.