Abstract
A major public health concern in the world, particularly in sub‐Saharan African countries, epilepsy is poorly studied in Niger, and its prevalence in the general population is unknown. Only two hospital‐based studies have been published in Niger, reporting an estimated mean hospital prevalence of epilepsy of 24.2% (95% CI: 23.2–25.2), mainly affecting patients younger than 18 years (54.6%, 95% CI: 52.2–57.0), and males (59.8%, 95% CI: 57.4–62.2). To date in Niger, people living with epilepsy (PWE) are usually cared for by non‐physician healthcare workers (mainly nurse technicians in mental health), general medical doctors (non‐specialist physician), and non‐neurologist physicians. In routine practice, these health workers make the diagnosis of epilepsy essentially based on the clinic, i.e., the repetition of epileptic seizures over time (mainly generalized tonic–clonic seizures) because most of them practiced in health centers or district hospitals or regional hospital centers in which electroencephalogram and neuroradiological explorations are of limited access or unavailable as well as a referral neurologist. Only 10 neurologists are currently practicing in Niger for a total population estimated at 21466800 inhabitants by the World Health Organization in 2018. In 41.8% (95% CI: 39.4–43.2) of the cases, the etiology was unknown with neuroradiological explorations and laboratory tests not performed in most cases. Genetic etiologies are the most frequent etiologies (40.8; 95% CI: 38.4–43.2), followed by Structural etiologies (11.7; 95% CI: 10.1–13.3) particularly hypoxic–ischemic brain injury, and infectious etiologies (6.8%; 95% CI: 5.6–8.0), especially cerebral malaria. PWEs are the target of social stigma and discrimination due to erroneous cultural and religious beliefs about epilepsy of the people from Niger. The present review is an update on the different aspects of epilepsy in Niger.
Keywords: clinical characteristics, epilepsy, Niger, sociocultural aspects, sub‐Saharan Africa
Key points.
Epilepsy represents the second cause of consultation in neurology after headaches in Niger.
Its hospital prevalence was estimated to be 24.2%, mainly affecting men and children and adolescents.
The care of PWE still faces problems such as the lack of neurologists, the lack of regular availability of ASMs, and limited access to paraclinical exams for the etiological workup.
In many rural areas, traditional healers are still consulted in the first intention by PWE or their families due to their erroneous beliefs and misconception about epilepsy.
1. INTRODUCTION
Epilepsy is a common chronic brain disease affecting people of all ages, sexes, races, income groups, or geographical locations. Around 7.6 per 1000 persons will have epilepsy during their lifetime, with a risk of premature death up to three times higher than that in the general population. 1 Epilepsy constitutes a major public health concern in the world particularly in developing countries, especially in sub‐Saharan African countries. It can have serious physical, psychological, and social consequences, including traumatic injuries, mental health disorders, and stigma and discrimination that lead to difficulties in education, employment, marriage, and reproduction.
A meta‐analysis estimated the global prevalence of epilepsy at 9.39 per 1000 in sub‐Saharan Africa, the region in which 59% (95% CI: 32–85) of people with epilepsy (PWE) do not take any antiseizure medications (ASMs). 2 The most common reasons reported in the same meta‐analysis, which explained the treatment gap were the lack of qualified personnel to diagnose epilepsy, the cost or relative unavailability of ASMs, and the cultural beliefs of patients and their families about epilepsy. In the 2022 report of the ILAE Task Force on access to treatment, barriers that prevent PWE in African countries from having access to ASMs were lack of awareness (50.0%), lack of medical expertise (38.9%), transport problems mainly distribution constraints (33.3%), and reliance on traditional healers (38.9%). 3
In Niger, there is little data on the different aspects of epilepsy. There is no door‐to‐door survey on epilepsy to estimate the prevalence of this condition in the general population in Niger. However, two hospital‐based studies on epilepsy have been published. 4 , 5 To date in Niger, PWEs are usually cared for by non‐physician healthcare workers (mainly nurse technicians in mental health), general medical doctors (non‐specialist physician), and non‐neurologist physicians. In routine practice, these health workers make the diagnosis of epilepsy essentially based on the clinic, that is, the repetition of epileptic seizures over time (mainly generalized tonic–clonic seizures) because most of them practiced in health centers or district hospitals or regional hospital centers in which electroencephalogram and neuroradiological explorations are of limited access or unavailable as well as a referral neurologist. Their care for PWE mainly consists of ASM prescription and neuroradiological exploration for the etiological workup of epilepsy is performed only by some general medical doctors or non‐neurologist physicians. Only 10 neurologists are currently practicing in Niger (six in the different hospitals of Niamey, two in the reference hospital of Maradi, one in the reference hospital of Zinder, and one in a medical neurological clinic in Agadez only from 2022 [Figure 1]) for a total population estimated at 21466800 inhabitants by the World Health Organization (WHO) in 2018. 6 According to a survey on epilepsy management carried out among the 10 neurologists practicing in Niger, of whom five responded to the questionnaire, epilepsy was the second most common cause of consultation in neurology after headaches in Niger (findings not published). The present review is an update on the different aspects of epilepsy in Niger.
FIGURE 1.
Geographical distribution of the 10 neurologists practicing in Niger and also the distribution of the different regions of this country.
2. INCIDENCE AND PREVALENCE
No study on the incidence and prevalence of epilepsy in Niger has been conducted, and therefore, there are no data on this to date. However, two hospital‐based studies on epilepsy have been published. 4 , 5 The first study was conducted in Niamey in a tertiary care center in a neurological unit and reported a hospital prevalence of 29.5%. 4 In the above study, the diagnosis of epilepsy was considered in case of at least two unprovoked (or reflex) seizures occurring more than 24 h apart or one unprovoked (or reflex) seizure in individuals who have risk factors such as cerebrovascular disease, central nervous system infection, and traumatic brain injury according to the 2014 revised definition of epilepsy of ILAE Official report. 7 The second study was conducted in Tahoua in a secondary care center in a psychiatric unit and reported a hospital prevalence of 12.2%. 5 The diagnosis of epilepsy was considered in the case of repetition of epileptic seizures over time in this study. The mean hospital prevalence was estimated to be 24.2% (95% CI: 23.2–25.2) (Table 1). The high difference in prevalence between the two studies could be explained by the fact that the study of Niamey was conducted in a department of neurology, the only center in the country until 2018, attracting people with neurological conditions from all parts of Niger (Figure 1).
TABLE 1.
hospital prevalence, sociodemographic characteristics, etiologies, epilepsy syndromes, and treatment.
| Variables | Study of Niamey [4] | Study of Tahoua [5] | Overall (95% CI) |
|---|---|---|---|
| Level of the study center | Tertiary | Secondary | — |
| Year | 2019 | 2021 | — |
| Study design | Retrospective | Retrospective | — |
| Population size | 4576 | 2022 | 6598 |
| Number of people with epilepsy | 1350 | 246 | 1596 |
| Hospital prevalence (%) | 29.5 | 12.2 | 24.2 (23.2–25.2) |
| Sociodemographic characteristics | n = 1350 | n = 246 | 1596 |
| Mean age (years) | 18.55 | 22.38 | 20.46 |
| Age groups (years) | |||
| 0–17 | 771 (57.1) | 100 (40.6) | 871 (54.6 [52.2–57.0]) |
| 18–37 | 392 (29.0) | 122 (49.6) | 514 (32.2 [29.9–34.5) |
| 38–59 | 125 (9.3) | 20 (8.2) | 145 (9.1 [7.7–10.5]) |
| ≥ 60 | 62 (4.6) | 4 (1.6) | 66 (4.1 [3.1–5.1]) |
| Gender group | |||
| Males | 812 (60.1) | 142 (57.7) | 954 (59.8 [57.4–62.2]) |
| Females | 538 (39.9) | 104 (42.3) | 642 (40.2 [37.8–42.6]) |
| Age groups of first seizures (years) | |||
| <19 | ‐ | 147 (59.7) | ‐ |
| 20–49 | ‐ | 90 (36.6) | ‐ |
| ≥50 | ‐ | 9 (3.7) | ‐ |
| Etiology | |||
| Structural | 164 (12.1) | 23 (12.2) | 187 (11.7 [10.1–13.3]) |
| Cerebrovascular disease | 39 (2.9) | 4 (1.6) | 43 (2.7 [1.9–3.5]) |
| Traumatic brain injury | 14 (1.0) | 12 (4.9) | 26 (1.6 [1.0–2.2]) |
| Brain tumors | 8 (0.6) | — | — |
| Arteriovenous malformation | 2 (0.1) | — | — |
| Hypoxic–ischemic brain injury | 101 (7.5) | 7 (2.8) | 108 (6.8 [5.6–8.0]) |
| Infectious | 24 (1.7) | 66 (26.8) | 90 (5.6 [4.5–6.7]) |
| Cerebral malaria | 18 (1.3) | 46 (18.7) | 64 (4.0 [3.0–5.0]) |
| Bacterial meningitis | 2 (0.1) | 20 (8.1) | 22 (1.4 [0.8–1.9]) |
| Cerebral toxoplasmosis | 2 (0.1) | — | |
| Cerebral tuberculosis | 2 (0.1) | — | |
| Genetic | 652 (48.3) | — | 652 (40.8 [38.4–43.2]) |
| Idiopathic generalized epilepsies | 622 (46.1) | — | — |
| Childhood absence epilepsy | 119 (8.8) | — | — |
| Juvenile absence epilepsy | 71 (5.3) | — | — |
| Epilepsy with GTCA | 377 (27.9) | — | — |
| Juvenile myoclonic epilepsy | 55 (4.1) | — | — |
| Epileptic encephalopathy | |||
| Myoclonic epilepsy in infancy | 30 (2.2) | — | — |
| Metabolic | — | — | — |
| Immune | — | — | — |
| Unknown | 510 (37.8) | 157 (63.9) | 667 (41.8 [39.4–44.2]) |
| Epilepsy syndromes | |||
| Childhood absence epilepsy | 119 (8.8) | — | — |
| Juvenile absence epilepsy | 71 (5.3) | — | — |
| Juvenile myoclonic epilepsy | 55 (4.1) | — | — |
| Epilepsy with GTCA | 377 (27.9) | — | — |
| Myoclonic epilepsy in infancy | 30 (2.2) | — | — |
| West syndrome | 34 (2.5) | — | — |
| HHE syndrome | 22 (1.6) | — | — |
| Unknown | 642 (49.2) | — | — |
| Treatment | |||
| Sodium valproate | 657 (48.7) | 112 (45.5) | 769 (48.2 [45.7–50.7]) |
| Carbamazepine | 370 (27.4) | 81 (32.9) | 451 (28.3 [26.1–30.5]) |
| Phenobarbital | 464 (34.4) | 97 (39.4) | 561 (35.1 [32.8–37.4]) |
| Lamotrigine | 11 (0.8) | ‐ | ‐ |
| Drug resistance | 130 (9.6) | 7 (2.8) | 137 (8.6 [7.2–10.0]) |
| Poor drug compliance | 167 (12.4) | ‐ | ‐ |
Note: GTCA indicates generalized tonic–clonic seizures alone; HHE syndrome, hemiconvulsion‐hemiplegia‐epilepsy syndrome.
3. SOCIODEMOGRAPHIC CHARACTERISTICS AND ETIOLOGIES OR EPILEPSY SYNDROMES
The two hospital‐based studies published in Niger reported a predominance of epilepsy in men (59.8%; 95% CI: 57.4–62.2) and a mean age of 20.46 years with a proportion of patients younger than 18 years of 54.6% (95% CI: 52.2–57.0) (Table 1). The age of the first epileptic seizure was less than 20 years in about 60% of patients. 5 Patients aged ≥60 years, considered elderly in a hospital‐based study conducted in Niger in 2019, 8 representing 4.1% (95% CI: 3.1–5.1). This prevalence of epilepsy among people aged 60 years and older in Niger seemed near to that reported in a systematic review among people aged 60 years or older in sub‐Saharan Africa, which ranged from 0.02% to 3.2%. 9
In 41.8% (95% CI: 39.4–43.2) of the cases, the etiology was unknown. This high prevalence of epilepsy of unknown etiology could be explained by the fact that PWE or their families have limited access to neuroradiological explorations and laboratory tests, or due to the unavailability of these examinations or to the lack of financial resources. The cost of measurement of antineuronal antibodies limited access to these lab tests for most PWE or their families, especially since they are unavailable in Niger would explain the absence of immune etiology in the two hospital‐based studies conducted in Tahoua and Niamey.
Brain infections represented 5.6% (95% CI: 4.5–6.7) of etiologies and were mainly represented by cerebral malaria (4.0%; 95% CI: 3.0–5.0). Neurocysticercosis is the most common brain infection and a major cause of epilepsy in many African countries. 2 Cysticercosis is rare in Niger, a country with a predominantly Muslim population where there is little contact between humans and pork and where pork is not consumed, making low the risk of infection with adult worms or environmental contamination by parasite eggs. Hypoxic–ischemic brain injury was the most common structural etiology (6.8%; 95% CI: 5.6–8.0), followed by cerebrovascular disease (2.7%; 95% CI: 1.9–3.5), and traumatic brain injury (1.6%; 95% CI: 1.0–2.2). The study of Niamey conducted in a department of neurology reported a high proportion of genetic etiologies (48.3%) mainly represented by epilepsy with generalized tonic–clonic seizures alone. 4 The authors explained this high proportion of genetic etiologies by the strong representation of patients younger than 18 years (57.1%), an age group in which the prevalence of genetic etiologies is high. In addition, people younger than 15 years also represented 51.4% of the general population in Niger, according to WHO data in 2018. 6 In the same study of Niamey, hemiconvulsion‐hemiplegia‐epilepsy syndrome (an epileptic syndrome that has become rare due to early and adequate management of fever and febrile convulsions in children) was reported in 1.6% of patients, and the cases had been taken over and described in detail in another study. 10
4. SOCIOCULTURAL ASPECTS
In developing countries, epilepsy is a major public health concern associated with a strong social stigma and discrimination against PWE particularly in the school environment. In Niger, two surveys among primary and secondary school teachers about the sociocultural aspects of epilepsy have been published. 11 , 12 Epilepsy was considered a demonic possession in 11.9% (95% CI: 8.8–15.0) and 43.4% (95% CI: 38.7–48.1) as a contagious disease (Table 2). The main modes of contagion reported were contacted with the place where the PWE fell during the seizure in 31.0% (95% CI: 26.6–35.4) and physical contact with a PWE or with his saliva or urine in 15.6% (95% CI: 12.2–19.0). Epilepsy was considered an untreatable condition by 11.9% of participating school teachers (95% CI: 8.8–15.0). About 73% of the participants would not allow their children to marry a PWE. These erroneous cultural and religious beliefs about epilepsy are not only prevalent in the school environment but also in the general population in Niger and are responsible for the social stigma and discrimination against PWE. Even in the paramedical sector in Niger, these erroneous cultural and religious beliefs were also observed. A study conducted in 2020 in Niamey among 98 nurses showed that epilepsy was considered a demonic possession and a contagious disease by 9.2% and 19.4% of participants, respectively. 13 In the same study, epilepsy was considered an untreatable condition by 5.1% of the participating nurses.
TABLE 2.
Sociocultural aspects.
| Study of Niamey [11] | Study of Tahoua [12] | Overall (95% CI) | |
|---|---|---|---|
| Study design | Cross‐sectional survey | Cross‐sectional survey | — |
| Year | 2020 | 2020 | — |
| Study population | Primary and secondary school teachers | Primary and secondary school teachers | — |
| Number of participants | 145 | 284 | 429 |
| Epilepsy as a psychiatric illness | 23 (15.9) | 92 (32.4) | 115 (26.8 [22.6–31.0]) |
| Epilepsy as a witchcraft | 14 (9.7) | 11 (3.9) | 25 (5.8 [3.6–8.0]) |
| Epilepsy as a demon possession | 5 (3.4) | 46 (16.2) | 51 (11.9 [8.8–15.0]) |
| Epilepsy as a brain disease | 61 (42.1) | 88 (31.0) | 149 (34.7 [32.4–37.0]) |
| Epilepsy as a hereditary disease | 16 (11.0) | 38 (13.4) | 54 (12.6 [9.3–15.9]) |
| Epilepsy as a contagious disease | 67 (46.2) | 119 (41.9) | 186 (43.4 [38.7–48.1]) |
| Contagiousness by physical contact with an epileptic person or their saliva or urine | 37 (25.5) | 30 (10.6) | 67 (15.6 [12.2–19.0]) |
| Contagiousness by contact with the place where the person fell during the seizure | 38 (26.2) | 95 (33.5) | 133 (31.0 [26.6–35.4]) |
| Epilepsy as an incurable disease | 10 (6.9) | 41 (14.4) | 51 (11.9 [8.8–15.0]) |
| Participants that would not allow their child to marry someone with epilepsy | — | 208 (73.2) | – |
To date, any study has been conducted in Niger among traditional healers to explore how they diagnosed epilepsy and cared for PWE. In many rural areas of Niger, these traditional healers are still consulted in the first intention by PWE or their families because their erroneous beliefs lead them to believe that epilepsy, which they consider a demonic possession, can only be treated by traditional medicine.
5. TREATMENT
To date, only medical treatment for epilepsy is available in Niger. Epilepsy surgery is not yet available. According to the survey conducted among the 10 neurologists practicing in Niger, of whom only five had agreed to participate, many patients had consulted a traditional healer before seeing a neurologist, all because of the failure of traditional treatment.
The most commonly used ASMs in the two hospital‐based studies published in Niger were sodium valproate, carbamazepine, and phenobarbital as monotherapy or in combination. Only lamotrigine has been used among the newer generations of ASMs (Table 1). According to the findings of our survey on epilepsy management among neurologists practicing in Niger, sodium valproate was the most used molecule in 60% of the cases.
Drug‐resistant epilepsies represented 8.6% (95% CI: 7.2–10.0) of cases in Niger. In the two hospital‐based studies, epilepsy was considered drug‐resistant in case of failure to achieve sustained seizure freedom despite adequate trials of two well‐tolerated, appropriately chosen and used ASMs prescribed as monotherapies or in combination according to the definition of drug‐resistance proposed by ILAE. 14 Poor drug compliance (PDC) was reported in 12.4% of cases in the study of Niamey. 4 PDC was considered when epileptic seizures are well controlled in the case of regular drug intake and then in the case of recrudescence of epileptic seizures when drug intake is imperfect or irregular (drug intake jump). The reasons for this PDC were the cost of ASMs to PWE or their families for long‐term treatment and their erroneous religious and cultural beliefs.
The main difficulties reported by the five neurologists who responded to our survey questionnaire on epilepsy management in Niger were as follows: (1) limited access to neuroradiological explorations and laboratory tests, either due to the unavailability of these examinations or due to the lack of financial resources in PWE or their families, (2) low‐income of PWE or their families, which does not allow them to buy ASMs regularly for long‐term treatment, (3) the lack of regular availability of ASMs, especially those of the newer generations, and (4) erroneous religious and cultural beliefs of PWE or their families that are partly responsible for PDC.
6. PERSPECTIVES
To change the erroneous religious and cultural beliefs in the general population and also to improve the quality of life of PWE by reducing social stigma and discrimination, information and awareness campaigns are organized and transmitted from time to time via national public social media. Every year on International Epilepsy Day, free consultations are also organized to allow PWE who do not have the financial resources to be seen by a neurologist. These actions will be continued over time. In addition, the health structures and the Ministry of Public Health will be required to help ensure access to neuroradiological explorations and laboratory tests and the regular availability of ASMs.
7. CONCLUSION
The second cause of consultation in neurology after headaches in Niger, epilepsy still remains a major public health concern that requires special attention from the Ministry of Public Health authorities. Information and awareness campaigns for the general population via national public social media should be supported by the Ministry of Public Health of Niger and other international epilepsy organizations to reduce social stigma and discrimination. In addition, measures to ensure easy access and regular availability of ASMs for PWE are needed, as well as laboratory tests and neuroradiological explorations.
CONFLICT OF INTEREST STATEMENT
The author has any conflict of interest to disclose. The author confirms that he has read Journal's position on issues involved in ethical publications and affirms that this report is consistent with those guidelines.
ACKNOWLEDGMENTS
None.
Toudou‐Daouda M. Epilepsy in Niger: An overview of the current situation. Epilepsia Open. 2023;8:278–284. 10.1002/epi4.12742
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