versão impressa ISSN 1676-2649
J. epilepsy clin. neurophysiol. vol.17 no.4 Porto Alegre 2011
Effectiveness of the use of an omega 3 and omega 6 combination(EquazenTM) in paediatric patients with refractory epilepsy
Eficácia do uso de uma combinação de ômega 3 com ômega 6 (EquazenTM) em pacientes pediátricos com epilepsia refratária
Eduardo Javier Barragán-PérezI; Irene Heredia-BarragánII; Rosana Huerta-AlbarranII
IPaediatric Neurologist. Attached to Paediatric Neurology Department, HIMFG. Profesor of Neuropediatrics, UNAM
IIPaediatric Neurologist. Federico Gómez Children's Hospital of Mexico (HIMFG)
INTRODUCTION: Epilepsy is considered a health problem. 85% of patients are satisfactorily controlled with antiepileptic drugs (AEDs) and 15% have refractory seizures. The combination of omega 3 and omega 6 fatty acids (EquazenTM) can contribute to changes in ionic currents and to stabilization of neurotransmitter's function resulting in cell membrane equilibrium. These changes lead to potential seizure control.
OBJECTIVE: To compare efficacy and safety in the treatment of refractory epilepsy with a supplement combining EPA, DHA (omega 3 fatty acids) and GLA (omega 6 fatty acids).
METHODS: We reviewed patients from the Neurology Department of the Children's Hospital of Mexico who have refractory epilepsy, evaluating clinical characteristics of seizures, number of seizures and AEDs. 792 mg of EPA, DHA and GLA per day (6 capsules of EquazenTM) were administrated for four weeks in order to assess the frequency of seizures as well as tolerability and probable side effects.
RESULTS: The study was conducted with a total of 13 patients with follow-up four weeks after the start of supplementation. We obtained a satisfactory clinical response with ≥ 80% decrease in the daily number of seizures in more than 60% of patient. The mean of number of seizures over all patients was reduced significantly from 26.61±37.2 to 5.92 daily. In addition a significant improvement in the neurocognitive capacity was observedin all patients.
CONCLUSION: The co-adjuvant supplementation with EquazenTM may result in a reduction of the number of seizures in refractory epilepsy having in addition significant impact on neurocognitive aspects. To enhance the quality of life of epileptic patient supplementation with a specific combination of EPA, DHA and GLA should be reconsidered.
Keywords: refractory epilepsy; omega 3, omega 6 fatty acids.
INTRODUÇÃO: epilepsia é considerada um problema de saúde em que 85% dos pacientes são satisfatoriamente controlados com drogas antiepilépticas (DAE) e 15% tem crises refratárias. A combinação de ácidos graxos ômega 3 e ômega 6 (EquazenTM) pode contribui em mudanças em correntes iônicas e estabilização de neurotransmissores, resultando em equilíbrio da membrana celular. Estas mudanças levam a potencial controle de crises.
OBJETIVO: comparar a eficácia e segurança suplementos combinando EPA, DHA (ácidos graxos ômega 3) e GLA (ácidos graxos ômega 6) no tratamento da epilepsia refrataria.
MÉTODOS: crianças com epilepsia refratária do Departamento de Neurologia do Hospital Infantil do México tiveram avaliadas as características de suas crises, frequência e numero de DAEs. EPA, DHA e GLA (6 capsulas de Equazem 729mg) foram administrados em um período de 4 semanas, sendo acessados tolerabilidade, efeitos colaterais e frequência de crises.
RESULTADOS: 13 pacientes foram avaliados por 4 semanas após o início da suplementação. Um controle clínico satisfatório (redução de 80% ou mais das crises) foi obtido em 60% dos pacientes (26.61±37.2 crises para 5.92 crises ao dia), além de significativa melhora em sua capacidade neurocognitiva.
CONCLUSÃO: a suplementação de Equazen pode determinar redução no número de crises em epilepsia refratária e determinar melhora em parâmetros neurocognitivos. O uso da combinação EPA, DHA, GLA deveria ser reconsiderado neste cenário.
Unitermos: epilepsia refratária; ácidos graxos ômega 3, ômega 6.
Epilepsy is considered to be the most common paroxysmal event in childhood and is second only to mental retardation among neurological diseases1.
About 80-85% of the epilepsy patients are satisfactorily managed and treated with the classic antiepileptic drugs (AED) while 15-20% requires an alternative pharmacological option or even surgical procedures2.
As epilepsy is one of the main causes for attending our institution (65% of all neurology consultations in the hospital) and despite the many treatments available, there remain 15% of epileptic patients who do not respond to drug therapies. Therefore it is important to look for alternative treatments, especially for those, which can sustain seizure control thereby reducing the secondary complications like somnolence or cognitive decline. They may also be expected to offer economically more accessible options and have an impact on quality of life.
According to some authors, up to 30% of epilepsy cases have intractable seizures or adverse reactions to the medication, while other authors consider that only 5% to 10% cannot be controlled with the known drugs and these are categorized as difficult-to-control or refractory epilepsies2.
Refractory epilepsy (RE) is defined as a lack of seizure control, despite the correct diagnosis being made and the use of at least two antiepileptic drugs indicated for epilepsy at the maximum tolerated doses, with therapeutic serum levels being maintained for a minimum of six months3.
The specific combination of the fatty acids EPA, DHA (belonging to omega 3 polyunsaturated fatty acids) and GLA (omega 6 polyunsaturated fatty acids) may change the ion currents of the neurons, which sustain the normal neurotransmitters function for the synaptic transmission. The increased concentration of EPA, DHA and GLA in the central nervous system (CNS) may stimulate and sustain myelinisation resulting in stabilization of the cell membrane and possibly leading to control of epileptic seizures4.
The progression of epilepsy until it becomes a refractory process may be caused by changes in the cerebral circuits that are reorganized after the initial lesion or after status epilepticus or/and by the individual's genetic anomalies and variations (mutations and polymorphisms), which influence how the individual reacts to aggression and thus affects the development of the acquired symptomatic epilepsy. It is not to ignore that this clearly multifactorial condition can be related even to other aspects17.
One of the most important risk factors for developing refractory epilepsy is determined by the type of epilepsy. Patients with partial complex seizures have a higher rate of seizure recurrence than those who have generalized tonic-clonic seizures. Numerous studies have shown that symptomatic partial epilepsies are associated with a higher risk of resistance to treatment with antiepileptic drugs and seizure recurrence after an initial episode. On the other hand, the group of seizure-free patients is much larger among those with idiopathic generalized epilepsy than those with cryptogenic and symptomatic partial seizures20.
Since there remain cases of refractory epilepsy, regulating the co-factors by the administration of food supplements, such as a specific combination of omega 3 and 6 fatty acids (EquazenTM), has now been proposed. Apparently the supplement acts as a stabilizer of the post-synaptic membrane, which may sustain the treatment management with the different antiepileptic drugs12.
Although only a small number of patients suffer from difficult-to-control seizures, the socio-economic, medical and family consequences are very significant. These include adverse reactions to the multiple drug therapy, abnormal behaviours, long periods of hospitalization, multiple infectious complications and school failure. There are clinical and electroencephalographic factors which are associated with refractory epilepsy8.
The aim of our study is to compare the clinical response to treatment of refractory epilepsy by administration of a specific combination of omega 3 and omega 6 fatty acid (EquazenTM). It is a prospective, longitudinal pilot clinical trial. All patients (male and female) aged between 4 and 16 years attending the out-patients clinic of the Neurology Department, Children's Hospital of Mexico "Dr. Federico Gómez", and suffering from refractory epilepsy, regardless of the type of epilepsy (partial or generalized), were considered for inclusion in the trial. Patients who had previously been treated with a ketogenic diet or with omega 3 and omega 6 fatty acid supplements, surgery for epilepsy, patients with third-grade malnutrition, epilepsy of degenerative origin and systemic disease preventing administration of the diet were excluded.
The clinical characteristics of the epileptic seizures confirming the presence of refractory disease were assessed, their clinical presentation being evaluated by a neurologist in the outpatients department. The clinical identification of these characteristics was correlated with the electroencephalogram, although this was not the determining factor when classifying the site affected. The omega 3 and 6 fatty acid supplement (EquazenTM, Vifor Pharma) was added at a dose of six capsules a day (558 mg EPA, 174mg DHA and 60mg GLA) for four weeks. The patients' neuroimaging results as well as the drug treatment they were taking were analysed.
The patients were followed up in the Neurology Department by means of a seizure diary to find out the number and characteristics of their seizures. A baseline conventional electro-encephalogram was taken and followed up after four weeks. Clinical assessment was also conducted two and four weeks after patients started the diet.
The Clinical Global Impression (CGI) severity scale was completed by the parents and the investigator. The patients for whom a paediatric and neurological clinical history as well as a general physical and neurological examination were carried out were assessed during the period from September 2009 to June 2010.
The SPSS for Windows statistics package was used. Descriptive statistical analysis was performed to analyse the data distribution by means of frequency tables, measures of central tendency and scatter, histograms, pie charts and normal curves. The results for the different variables were analysed by non-parametric hypothesis testing for independent samples to compare two means (Mann-Whitney U-test or Wilcoxon). Non-parametric one-way ANOVA for paired groups was also used to compare more than two means (X2 Friedman and Kendall's). In all the results, the statistical significance was set at α=0.05 with 95% confidence intervals.
A total of 13 patients with a diagnosis of refractory epilepsy, who fulfilled the inclusion criteria, were included in the trial. Seven were male (53.84%) and six female (46.15%). Their mean age was 8.46±3.86 years and the age group distribution was as follows: pre-school 30.76% school age 30.76%, adolescent 38.46%. The distribution of the number of antiepileptic drugs used was as follows: two antiepileptic drugs in 38.46%, three drugs in 53.84% and finally four antiepileptic drugs were used in only one patient (7.69%).
In terms of the type of seizures, 61.43% were partial and 38.46% were generalized.
We observed a significant improvement in the neurocognitive capacity of all the patients and in the patients' quality of life, assessed by the CGI. The improvement was not directly related to the decreased frequency of seizures. A decrease of more than 4 points was observed.
During the study each patient received 792 grams daily of omega 3 and omega 6 for one month. Every week a meeting with the family and the patient was arranged in order to check the mean number of seizures per day recorded in the patient's diary.
At basis (without supplementation) a mean number of 26.61 seizures was obtained. This mean number of seizures decreased to 11.30 by the first week, to 10.76 in the second week, to 8.76 in the third week and finally to 5.92 in the fourth week (see Table 1). In terms of the mean, a statistically significant decrease of more than 75% in the daily number of seizures was therefore found after 4 weeks of supplementation compared to the base before supplementation (p<0.05).
The Figure 1 shows the decrease in the weekly number of seizures per patient before and after one to 4 weeks of supplementation with the omega 3 and omega 6 combination.
Overall a decrease of the daily seizures number was observed after the first week as also to the 4 week compared to the number before supplementation. Only patient number 5 did not show any decrease. Patient number 11 had a slightly increase of the daily epileptic seziures.
The Figure 2 shows the weekly number of seizures from week 2 to 4 after the start of supplementation.
The results for the different variables were analysed by means of non-parametric hypothesis testing for independent samples to compare two means (Wilcoxon). Significant differences with a two-tailed test were found) by comparing the daily mean seizures numbers after week 1 (11.30) and week 4 (5.92) (p=0.008). No increase in the number of seizures was found in any patient. The number of daily seizures decreased in 8 patient and remained unchanged in 5. Significant differences of the daily seizures number were also found when comparing week 1 (11.30) and week 3 (8.76) (p=0.032), but not between week 1 and week 2 (10.76; p=0.623), as shown in Table 1.
Non-parametric one-way ANOVA for paired groups was also used. In all the results the statistical significance level was set at a=0.05 with 95% confidence intervals.
When ANOVA was used, all the tests were statistically significant but our hypothesis was only corroborated when comparing the number of seizures before administration of the omega 3 and 6 supplementation and the second and fourth weeks, not in the third and first weeks (taking into account the F-values in the tables corresponding to degrees of freedom in our study, F=43.39 as shown in Table 2 above).
Epilepsy is recognized worldwide as a public health problem, with a prevalence ranging from 1.5 to 10.8 per 1000 people. This has major repercussions for working and social life as well as health, exacerbating socio-economic conditions (which are already unstable in Mexico), given the daily struggle to maintain the cost of antiepileptic drugs.
The fact that only 80-85% of patients with epilepsy are satisfactorily controlled with antiepileptic drugs (AED) forces us to search for more treatment options for the remaining percentage (10-15%) who meet the criteria for refractory epilepsy.
The group of patients studied in the present trial was heterogeneous, with characteristics and criteria consistent with the diagnosis of refractory epilepsy. Given the study objective, the efficacy of the fatty acids omega 3 and omega 6 (EquazenTM) as additive therapy for refractory epilepsy is demonstrated in the paediatric population of the Children's Hospital of Mexico.
The most interesting finding from our study, which was not currently the first study objective, is the presence of an improvement in 100% of patients in their neurocognitive capacity and their quality of life, assessed by the CGI. This was not found to be related to the effect of the fatty acids omega 3 and omega 6 in terms of ≥80% decrease in the daily number of seizures in 60% of patients. This effect was regarded as another independent effect on neurocognitive capacity, which suggests that the usefulness of an omega 3 and omega 6 combination as a co-adjuvant supplement should also be reconsidered in the overall improvement of epilepsy patients.
In this study our hypothesis that the combination of EPA, DHA and GLA reduces the frequency of the number of seizures in patients with refractory epilepsy is proved. While the statistical tests (Wilcoxon and ANOVA) vary in significance on this point before four weeks, they both agree that by week 4 there is a decrease associated with administration of the supplementation. This might be explained by the time the supplement needs to be administered in order to reach adequate therapeutic levels.
According to our study, the response to EquazenTM as additive treatment to antiepileptic drugs reduces the seizure frequency by 80% in more than 60% of the total number of patients studied.
Its impact on neurocognitive aspects in 100% of patients, observed at the same time, gives cause to reconsider its usefulness in the comprehensive improvement of epileptic patients.
Vifor Pharma provided the supplement for this study. The staff of the neurology department, HIM, is acknowledged for supporting the study.
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Address for correspondence:
Eduardo Barragán Pérez
Av. Cuauhtémoc, 882 Col Narvarte Poniente
CP 03020, Delegación Benito Juárez, México DF, Mexico
Received Oct. 25, 2011; accepted Dec. 07, 2011.