Reduction of Two-Drug Therapy in Intractable Epilepsy

The effects of reducing two-drug treatment to single-drug therapy were studied prospectively in 36 patients with intractable complex partial seizures. In 30 patients (83%) this was possible without an increase in seizure frequency. In six patients (17%) the number of seizures was higher during single-drug therapy. The slow transfer was not complicated by unwanted withdrawal effects. The plasma concentration of the single drug was raised if necessary until clinical drug toxicity was observed. An improvement in seizure control was surprisingly noted in 13 patients (36%). In two patients seizures were completely controlled. In one patient a seizure reduction of 87% was observed. The number of patients with clinical side effects was similar during two-drug and single-drug therapy. The number of side effects was lower during single-drug therapy. Reduction of polypharmacy may be beneficial for patients with intractable epilepsy.     

Efficacy of Clobazam as Add-On Therapy in Patients with Refractory Partial Epilepsy

PURPOSE: Clobazam (CLB) has an important antiepileptic effect and is less expensive than the new antiepileptic drugs (AEDs), but still has not been considered as first-line drug in the treatment of epilepsy. We evaluated the efficacy of CLB as add-on therapy in patients with refractory partial epilepsy. METHODS: This was an open, retrospective study, conducted at the epilepsy clinic of our university hospital. All patients had chronic epilepsy and were being evaluated for epilepsy surgery. CLB was introduced as add-on therapy (starting with 10 mg/ day) in patients with previous failure of at least two AEDs. Information was obtained from clinical notes and follow-up visits. RESULTS: We evaluated 97 patients, 37 men and 60 women. Ages ranged from 15 to 70 years (mean, 35.8 years). Etiology of epilepsy was hippocampal atrophy in 67 (69%), cortical dysgenesis in nine (9.3%), and other etiologies in nine (9.3%). In 12 (12.3%) patients, the etiology of epilepsy was not identified despite clinical and neurologic investigation. Patients used CLB for a period ranging from 1 month to 7 years and 9 months (mean, 16.7 months) with doses ranging from 10 to 60 mg/day (mean, 29.7 mg/day). Seven (7.2%) patients were seizure free, 48 (49.4%) had > or =50% of improvement in seizure control, 39 (40.2%) had <50% of improvement in seizure control, and in three (3.1%), no data were available. CONCLUSIONS: We conclude that CLB may have efficacy equivalent to that of the new AEDs when used as add-on therapy in patients with refractory epilepsy. CLB should be considered an economic alternative in the treatment of patients with refractory epilepsy.     

Vagus nerve stimulation for refractory idiopathic generalised epilepsy.

We reviewed our experience with vagus nerve stimulation (VNS) in 165 patients with medically refractory epilepsy (138 partial epilepsy (PE), 13 symptomatic generalised epilepsy (SGE), 14 idiopathic generalised epilepsy (IGE)). Average duration of VNS therapy was 21.6 months. A 50% or greater reduction in seizure frequency was achieved in 47.1% of the PE group, 46.1% of the SGE group, and 57.1% of the IGE group. A 50% or greater reduction in seizure frequency and reduced antiepileptic drug (AED) regimen were achieved in: PE (9.4%), SGE (7.7%), and IGE (35.7%). These preliminary results suggest that VNS is an effective therapy for some patients with medically refractory IGE.     

Vagal nerve stimulation in tuberous sclerosis complex patients

This is an open-label, retrospective, multicenter study to determine the outcome of intermittent stimulation of the left vagal nerve in children with tuberous sclerosis complex and medically refractory epilepsy. The records of all children treated with vagal nerve stimulation were reviewed in five pediatric epilepsy centers to locate those with tuberous sclerosis complex who had been treated with vagal nerve stimulation for at least 6 months. These patients were compared with (1) a series of patients obtained from the literature, (2) 10 similar control patients with epilepsy obtained from a registry of patients receiving vagal nerve stimulation, and (3) four published series of tuberous sclerosis complex patients whose epilepsy was surgically managed. Ten tuberous sclerosis complex patients with medically refractory epilepsy treated with vagal nerve stimulation were found. Nine experienced at least a 50% reduction in seizure frequency, and half had a 90% or greater reduction in seizure frequency. No adverse events were encountered. Comparison with published and registry patients revealed improved seizure control in the tuberous sclerosis complex patients. Comparison with the group undergoing seizure surgery demonstrated improved outcomes after surgery. Vagal nerve stimulation appears to be an effective and well-tolerated adjunctive therapy in patients with tuberous sclerosis complex and seizures refractory to medical therapy. Resective surgery has a better prospect for improved seizure control.     

Lacosamide in refractory mixed pediatric epilepsy: a prospective add-on study

Lacosamide is a new antiepileptic drug that is currently approved by the US Food and Drug Administration (FDA) for adults 17 years or older for partial-onset seizures. The authors reviewed 21 pediatric patients (<17 years) with various seizure types who were started on oral lacosamide as part of a prospective add-on study as adjunctive therapy for refractory epilepsy. Five patients were excluded due to less than 3 months of meaningful follow-up. Maintenance dosages used ranged from 2.4 to 19.4 mg/kg/d. Eight of 16 (50%) patients had greater than 50% reduction in seizure frequency with adjunctive lacosamide therapy. Eight (50%) patients had generalized epilepsy including 4 with Lennox-Gastaut syndrome. Lacosamide was effective therapy for most seizure types but was particularly effective for partial-onset seizures. Lacosamide was effective in treating 5 of 8 (62.5%) localization-related epilepsies but only 2 of 8 (25%) generalized epilepsies, both Lennox-Gastaut syndrome patients with greater than 90% seizure reduction. None of these very refractory patients remained seizure free.     

The natural history of epilepsy in tuberous sclerosis complex

Background : Although epilepsy affects most patients with tuberous sclerosis complex (TSC), little is known about the natural history of epilepsy in this genetic disease. Methods : A retrospective chart review of all patients with TSC seen between January 2002 and October 2008. Charts were reviewed for a history of infantile spasms (IS), seizure other than IS, refractory epilepsy, Lennox‐Gastaut syndrome (LGS), anticonvulsant medication use, ages of seizure onset, last seizure, last clinic visit, clinical seizure phenotype(s), cognitive impairment, and genetic mutation. Results : Two hundred ninety‐one patients were included. Among these patients, 37.8% had a history of IS; 85.2% had a history of seizure; 54.1% developed multiple seizure types, not including IS; 63.2% had seizure onset in the first year of life; and 12.1% of adults without a seizure history developed epilepsy. Of epilepsy patients, 62.5% developed refractory epilepsy and 33.5% achieved epilepsy remission; 37.5% of these patients achieved medication freedom. IS was a risk factor for refractory epilepsy (p<0.0001) and LGS (p<0.0001). History of seizure, IS, age at seizure onset, and refractory epilepsy each correlated with poor cognitive outcome (p<0.0001). Epilepsy remission correlated with better cognitive outcome (p<0.0001). TSC2 was a risk factor for IS and epilepsy; patients without an identified mutation were more likely to achieve remission. Conclusion : Most patients with TSC develop epilepsy and most develop multiple seizure types. Onset typically occurs in the first year of life; however, adults remain at risk. Although refractory epilepsy is common, many patients achieve seizure control. Many features of seizure history are predictive of cognitive and epilepsy outcome.     

Use of topiramate in childhood generalized seizure disorders

Topiramate is a sulfamate derivative of the naturally occurring monosaccharide D-fructose. It was initially approved in the United States as adjunctive therapy for partial seizures in 1997. However, there is increasing evidence that it is effective in the treatment of generalized seizures and epilepsy syndromes. Initially, open-label studies using topiramate as add-on therapy in children with refractory generalized seizure types were performed. These showed improvement in patients with the following generalized seizure types: typical and atypical absence, atonic, myoclonic, generalized tonic-clonic, and juvenile myoclonic epilepsy. Double-blind, placebo-controlled multicentered studies in patients with refractory primary generalized tonic-clonic seizures and epilepsy syndromes were performed. The median reduction in seizure frequency for primary generalized tonic-clonic seizures was 56.7% for topiramate and 9% for placebo. Additionally, 13.6% of topiramate-treated patients were primary generalized tonic-clonic seizure free for the study period. In the topiramate-treated juvenile myoclonic epilepsy patients, primary generalized tonic-clonic seizures were reduced > 50% in 73% of patients. Open-label extension showed that primary generalized tonic-clonic seizures were reduced >50% in 63% of topiramate-treated patients for > or = 6 months, and 16% were primary generalized tonic-clonic seizure free > or = 6 months. Accumulating evidence suggests that topiramate has a broad spectrum of antiepileptic effect. Moreover, life-threatening organ toxicity has not been attributed to topiramate. Topiramate is an effective treatment for refractory generalized seizure types and epilepsy syndromes encountered in children.     

The ketogenic diet as a treatment option in adults with chronic refractory epilepsy: efficacy and tolerability in clinical practice

The ketogenic diet (KD) is a high-fat, low-protein, low-carbohydrate diet that is used as a treatment for patients with difficult-to-control epilepsy. The present study assesses the efficacy and tolerability of the KD as an add-on therapy in adults with chronic refractory epilepsy. 15 adults were treated with the classical diet or MCT diet. During a follow-up period of 1 year we assessed seizure frequency, seizure severity, tolerability, cognitive performance, mood and quality of life (QOL). We found a significant reduction in seizures among the patients who followed the diet at least 1 year (n=5). Of these 5 patients, 2 had a reduction between 50 and 90%. Analyzing the study months separately, we found a seizure reduction of ≥50% in 26.6% of the patients during at least 1 month of treatment. Common side-effects were gastrointestinal disorders, loss of weight and fatigue. There was a considerable, non-significant improvement found in mood and QOL scores. Improvements were independent of reduction in seizure frequency, indicating that the effects of the KD reach further than seizure control.     

妥泰加用治疗成人难治性部分性癫痫的疗效观察

目的：观察妥泰（TPM）加用治疗成人难治性部分性伴或不伴随继发身性发作（GTCS）的疗效,安全性及耐受性。方法：56例在不动原用抗癫痫药（AEDs)的基础上加用TPM治疗20周、前8周为加量期,后12周为维持治疗的稳定期,治疗前（基础期）记录好作频率,用药情况。体重等作为自身对照。TPM自25mg/d开始,逐渐加量,目标剂量为200mg/d,治疗及治疗结束各查基础AEDs血药浓度进行比较,治疗结束行全面疗效分析。结果：TPM加用治疗20周后,与基础期发作频率比较,64．29％患者发作频率降低≥50％;25．00％,患者发生频率降低≥75％＜100％;16．07％完全不发。不良反应轻至中度,但与合AEDs的多少有关。50％患者体重可有不同程度的下降。TPM对止痛民西平及丙戊酸钠血药浓度影响不大。结论：TMP是治疗难治性部分性伴或不伴继发GTCS的表效的药物。     

左乙拉西坦治疗难治性癫痫48例的临床研究

目的：探讨左乙拉西坦（Lev）添加剂量治疗难治性癫痫的疗效和安全性。方法：采用开放性自身对照方法,对48例（儿童23例,成人25例）难治性癫痫患者进行Lev添加治疗,并随访1年以上,收集治疗后患者发作频率变化、无发作情况、不良反应以及退出原因。结果：Lev治疗难治性癫痫总有效率为64．58％,成人有效率高于儿童,对部分性癫痫综合征有效率高;3、6和12个月无发作率分别为6．25％、18．75％和16．67％,保留率为81．25％、56．25％和43．75％。总不良反应发生率为39．58％,无严重不良反应,退出的最主要原因为对疗效欠满意。结论：LEV是一种安全有效的难治性癫痫治疗药物,对部分性和全面性癫痫发作均有效。     

Clinical features and treatment of refractory epilepsy in children]

Clinical features of refractory epilepsy in children are symptomatic localization-related epilepsy, especially frontal lobe epilepsy, the onset in young age less than 3 years-old, and complication of developmental retardation. The treatments usually start with one drug of choice for specific seizure type. In the idiopathic epilepsy group, valproic acid was effective in 82% of the patients with generalized epilepsy and in 45% of localization-related epilepsy while carbamazepine was effective in 71% and 67%, respectively. However, in the refractory group which did not react to the drugs of choice at the initial treatment and continued to have seizures, no specific drugs were effective. Therefore, various kind of drugs, new or old, should be tried in sequence irrespective of the type of seizures. The seizure control was attained only in 10% (in the cases of CZP), and 17% (CLB) in localization-related epilepsy and in 9% (VPA), 12% (NZP) and 20% (ZNS) in generalized one in the refractory group. Although new drugs developed, the patients with refractory epilepsy do not tend to decrease in frequency and overall management including daily life or surgical therapy is mandatory for the children with refractory epilepsy.     

Monotherapy for partial epilepsy: focus on levetiracetam

Levetiracetam (LEV), the S-enantiomer of alpha-ethyl-2-oxo-1-pyrollidine acetamide, is a recently licensed antiepileptic drug (AED) for adjunctive therapy of partial seizures. Its mechanism of action is uncertain but it exhibits a unique profile of anticonvulsant activity in models of chronic epilepsy. Five randomized, double-blind, placebo-controlled trials enrolling adult or pediatric patients with refractory partial epilepsy have demonstrated the efficacy of LEV as adjunctive therapy, with a responder rate (>/=50% reduction in seizure frequency) of 28%-45%. Long-term efficacy studies suggest retention rates of 60% after one year, with 13% of patients seizure-free for 6 months of the study and 8% seizure-free for 1 year. More recent studies illustrated successful conversion to monotherapy in patients with refractory epilepsy, and its effectiveness as a single agent in partial epilepsy. LEV has also efficacy in generalized epilepsies. Adverse effects of LEV, including somnolence, lethargy, and dizziness, are generally mild and their occurrence rate seems to be not significantly different from that observed in placebo groups. LEV also has no clinically significant pharmacokinetic interactions with other AEDs, or with commonly prescribed medications. The combination of effective antiepileptic properties with a relatively mild adverse effect profile makes LEV an attractive therapy for partial seizures.     

Mozart K.448 acts as a potential add-on therapy in children with refractory epilepsy

Mozart's Sonata for two pianos in D major, K.448 (Mozart K.448), has been shown to improve mental function, leading to what is known as the Mozart effect. Our previous work revealed that epileptiform discharges in children with epilepsy decreased during and immediately after listening to Mozart K.448. In this study, we evaluated the long-term effects of Mozart K.448 on children with refractory epilepsy. Eleven children with refractory epilepsy were enrolled. All of the patients were diagnosed as having had refractory epilepsy for more than 1 year (range =1 year to 6 years 4 months, mean =3 years 11 months) and had been receiving at least two antiepileptic drugs (AED). During the study period, they listened to Mozart K.448 once a day before bedtime for 6 months. Seizure frequencies were recorded 6 months before they started listening to this music and monthly during the study period. All of the patients remained on the same AEDs during the 6-month study period. Frequencies of seizures were compared before and after listening to Mozart K.448. Eight of eleven patients were seizure free (N=2) or had very good responses (N=6) after 6 months of listening to Mozart K.448. The remaining three (27.3%) showed minimal or no effect (effectiveness <50%; unmodified or worsened seizure frequency). The average seizure reduction was 53.6 ± 62.0%. There were no significant differences in seizure reduction with IQ, etiology, or gender. We conclude that Mozart K.448 should be further studied as a potential add-on therapy in the treatment of children with refractory epilepsy.     

Oxcarbazepine reduces seizure frequency in a high proportion of patients with both newly diagnosed and refractory partial seizures in clinical practice.

The antiepileptic efficacy and tolerability of oxcarbazepine, used both as monotherapy and adjunctive therapy, were observed for 1 year in 202 adult patients, aged 17-83 years, with newly diagnosed or refractory partial epilepsy in clinical practice in Italy. At first observation, the seizure free rate was 72.2% in newly diagnosed patients given monotherapy, 40% in patients in whom oxcarbazepine replaced another monotherapy and 10.3% in patients given oxcarbazepine as adjunctive therapy. At least 50% reduction in seizure frequency was achieved in 90.7, 72 and 57%, respectively. Efficacy increased with the duration of treatment (p < 0.0001). In the 160 completers the seizure free rate was 61.3% with monotherapy and 28% with adjunctive therapy. 16.3% of patients reported adverse effects, mainly sedation and sleepiness; 5% discontinued oxcarbazepine because of adverse events. OXC is an effective and well-tolerated antiepileptic agent for the long-term treatment of partial epilepsy in adults.     

Practical prescribing and long-term efficacy and safety of zonisamide

Long-term efficacy, tolerability and safety of antiepileptic drug (AED) therapy is essential given the chronic nature of epilepsy. Zonisamide (Zonegran), a novel AED with a broad range of mechanisms of action contributing to its antiseizure efficacy, has been evaluated extensively for the long-term management of epilepsy. Open-label extension studies in the United States and Europe suggest continued efficacy of zonisamide in long-term treatment without development of adverse events further to those seen in registration studies. Baseline seizure frequency is reduced by approximately 40-70% during long-term treatment for up to 2 years, and 30-50% of patients attain >or=50% reduction in seizure frequency across all categories of seizure and durations of treatment. Preliminary data indicate a progressive decline in seizure frequency with continued zonisamide treatment. Zonisamide is well tolerated in long-term use, with a trend towards decreasing incidence of generally mild adverse events over time and a low rate of withdrawal during chronic use. Nephrolithiasis and other serious adverse events are infrequent, and can be minimised by appropriate management and patient education. This profile of maintained efficacy, tolerability and safety during sustained administration in combination with other AEDs supports zonisamide as a valuable adjunctive agent in the long-term management of refractory partial epilepsy.     

Long-term course of epilepsy in a large cohort of intellectually disabled patients.

This study was designed to describe the course of epilepsy (in terms of seizure frequency) and to assess the variables (antiepileptic therapy regimens and others) correlated to improvement. Seizure frequency (categories: seizure free, more than one seizure/year, monthly seizures, weekly seizures and daily seizures) and antiepileptic medication were retrospectively compared between 1992 and 2002 in a large cohort of 550 inpatients with chronic epilepsy and different degrees of intellectual disability or multiple handicaps. RESULTS: Seizure frequency decreased significantly (p<0.001). 218 of the 394 patients (55.3%) not seizure free in 1992 improved (changed into a better frequency category). The improvement rate was marginally higher in patients who had undergone a medication change (p=0.08). A high seizure frequency in 1992 (p=0.016) and older age (p=0.006), but not epilepsy syndrome or degree of intellectual disability, were predictors for improvement (stepwise logistic regression analysis). 56.4% of the improved patients were on combinations of two AEDs (17.4%, monotherapy; 20.2%, triple therapy). The most frequent therapy regimens in the improved patients were lamotrigine/valproate (48 patients), carbamazepine/phenobarbital (21) and carbamazepine only (19). Lamotrigine/valproate was effective in all kinds of epileptic syndromes. Most patients on lamotrigine had serum concentrations above 10microg/ml, approximately one half had dosages above 200mg/day. The rate of seizure freedom increased from 28.4 to 37.6%. The 84% of the patients seizure free in 1992 remained seizure free. Predictors for seizure freedom in 2002 were higher age (stepwise logistic regression, p<0.0005) and seizure freedom in 1992 (p<0.0005). CONCLUSIONS: Substantial improvement can be achieved even in intellectually disabled patients with chronic epilepsy. Although the rate of seizure freedom is reduced in comparison with a non-ID population, once seizure freedom has been achieved it is most likely to continue. For a majority of this patient population, monotherapy may not be sufficient. Lamotrigine/valproate appears to be a major therapeutic innovation.     

Lamotrigine–valproic acid combination therapy for medically refractory epilepsy

Purpose:   A retrospective study of lamotrigine (LTG)–valproic acid (VPA) combination therapy in medically refractory epilepsy.
Methods:   Patients were identified with an adult epilepsy clinic database and were included if they had been on LTG–VPA combination therapy for at least 6 months. Patient demographics and information about epilepsy type, severity, and degree of medical intractability were obtained by retrospective chart review. The primary outcome measure was change in baseline seizure frequency, and patients were stratified into three groups: (i) seizure-free, (ii) improved (at least 50% reduction in baseline seizure frequency), and (iii) not improved.
Results:   Thirty-five patients met all inclusion–exclusion criteria. Epilepsy type was generalized in 25 patients (71%) and partial in 10 patients (29%). Before LTG–VPA treatment, 27 of 35 (77%) experienced disabling seizures on a monthly basis, and 17 of 35 (49%) of patients had at least one disabling seizure per week. Patients had previously failed treatment with a median of five antiepileptic drugs (AEDs), alone or in combination. With LTG–VPA therapy, 18 (51.4%) remained completely seizure-free, four (11.4%) were improved, and 13 (37.1%) were unimproved. Median follow-up was 42 months. Of the 22 patients who improved, 11 had previously failed LTG and VPA monotherapy. There was no significant difference between improved and unimproved patients with respect to demographics, epilepsy type or severity, or number of previously failed AEDs.
Discussion:   The combination of LTG and VPA should be considered in patients with medically refractory epilepsy. The effectiveness of this combination appears to be independent of epilepsy type or patient demographics.     

Vigabatrin in the Treatment of Childhood Epilepsies: A Single-Blind Placebo-Controlled Study

Sixty-one pediatric patients (12-229 months of age) with refractory epilepsy were treated with vigabatrin [gamma-vinyl GABA (GVG)] in a 16-week, single-blind, add-on, placebo-controlled trial. Twenty-three patients (38%) showed a reduction of more than 50% in seizure frequency; 12 patients (20%) experienced a seizure increase; and the remaining 26 did not show significant differences between placebo and GVG treatment. Among the 216 patients who entered the long-term phase after having experienced more than 50% decrease in seizure frequency, 14 continued with the same degree of improvement after 2-11 months of follow-up (mean 7.7). GVG was particularly efficient in cryptogenic partial epilepsy. Conversely, nonprogressive myoclonic epilepsy tended to be aggravated. Agitation was the most commonly observed side effect, mainly at onset of therapy in mentally retarded patients, but was easily reversed by dose reduction. GVG is a promising drug in the treatment of refractory epilepsies of childhood.     

Cost-effectiveness of add-on therapy with pregabalin in patients with refractory partial epilepsy

PURPOSE: To estimate the cost-effectiveness of pregabalin as add-on therapy in patients with refractory partial epilepsy. METHODS: We developed a model to estimate clinical and economic outcomes over 1 year in a hypothetical cohort of patients with refractory partial epilepsy assumed alternatively to receive add-on therapy with pregabalin (300 mg/day) or no add-on therapy. For each patient in the model, we estimated the occurrence of seizure and side effects, using techniques of stochastic simulation. We assigned health-state utilities to each day of follow-up based on whether or not seizure or side effects were predicted to occur. Patients could discontinue therapy due to lack of efficacy or side effects. Outcomes included expected numbers of days without seizure ("seizure-free [SF] days"), quality-adjusted life-years (QALYs), and costs of therapy. Cost-effectiveness was assessed alternatively in terms of incremental cost per SF day gained and incremental cost per QALY gained. RESULTS: Add-on therapy with pregabalin was estimated to result in an average gain of 23.8 SF days over one year; the estimated additional cost of therapy was $678. Incremental cost (mean, 95% CI) per SF day gained was $28.45 ($27.25, $29.44); corresponding estimates of incremental cost per QALY gained were $52,893 ($49,249, $56,983). CONCLUSIONS: In patients with refractory partial epilepsy, the cost-effectiveness of pregabalin 300 mg/day compares favorably with published estimates of cost-effectiveness for other add-on antiepileptic drugs.     

Characteristics of refractory vs. medically controlled epilepsy patients with obstructive sleep apnea and their response to CPAP treatment

Obstructive sleep apnea (OSA) commonly coexists with epilepsy, and treatment of OSA may decrease seizure frequency. However, it is unclear whether patients with medically refractory epilepsy have a higher incidence of OSA compared with well-controlled epilepsy patients and whether the two groups carry different risk factors.PurposeThis study aimed to investigate the presence of OSA in patients with refractory vs. well-controlled epilepsy and their associated risk factors. We also assessed the benefits of treatment of OSA with continuous positive airway pressure (CPAP) in refractory epilepsy patients.MethodsWe retrospectively reviewed data from patients who presented to the Jacobs Neurological Institute Comprehensive Epilepsy Center of University at Buffalo from 2007 to 2010.ResultsThere is a tendency for much higher incidence of OSA in our epilepsy population compared with the general population (15.2% vs. 4.41%). For patients with well-controlled epilepsy, older age, male gender, and higher seizure frequency were predictors of a diagnosis of OSA. However, in medically refractory epilepsy patients, diabetes and snoring predicted a diagnosis of OSA. Treatment of OSA with CPAP in refractory epilepsy patients improved their seizure control (p < 0.02).ConclusionThis study confirms that OSA is common in epilepsy patients and treatment of OSA can improve seizure control in medically refractory cases. Patients with refractory epilepsy who have diabetes are more likely to have OSA.