Concomitant use of divalproex sodium and lamotrigine in developmentally disabled patients with epilepsy: a retrospective evaluation of efficacy and tolerability

Objective. Epilepsy in institutionalized severe developmentally disabled patients poses a therapeutic challenge. Frequently these patients have multiple seizure (sz) types that are often intractable. Both divalproex sodium (VPA) and lamotrigine (LTG) have demonstrated efficacy. We sought to examine the efficacy of this specific combination in a group of institutionalized, developmentally disabled patients with epilepsy.Methods. Medical and pharmacy records of all patients with developmental disabilities and intractable seizures were reviewed to identify those who had received VPA and LTG. This retrospective evaluation was structured with respect to time frame and outcome measure. Phase 1 consisted of baseline monotherapy with VPA. Phase 2 consisted of titration/dose escalation. Phase 3 was treatment observation period with the combination of both. Seizure frequency and adverse effect data were obtained from nursing or residential staff records. Primary outcome measures were change in seizure frequency between Phases 1 and 3. Additional measures were percentage of patients seizure-free and those with >75% reduction in seizures. A Wilcoxan signed rank test was used for statistical analysis.Results. Of 293 patients, 25 (12M/13F, 31.7+/-10.2 years) had VPA monotherapy following which LTG was added. Mean doses of VPA and LTG were 1474+/-728 and 165+/-111mg/day, respectively. Baseline seizure frequency ranged from 1 to 25 per month. Mean seizure frequency significantly decreased (6.5+/-vs2.0+/-4.0seizures/month, P<0.001). Sixty-four percent of these patients had >/=75% reduction in seizures 28% became seizure-free.Conclusions. The combination of VPA and LTG appears efficacious in this group of developmentally disabled patients with intractable seizures. Rash, which has been associated with this combination, was notably absent and this may reflect the slower titration schedule used.     

Juvenile Myoclonic Epilepsy: A 5-Year Prospective Study

Summary: We made a long term prospective study of 66 patients with juvenile myoclonic epilepsy (JME). Prevalence was 10.2% among 672 patients with epilepsies. Sex distribution was equal. Sixty-three were not diagnosed on referral; JME was not initially recognized in the epilepsy clinic in 22. Clinical typical absence seizures were reported in 33.3%, myoclonic jerks in 97% and generalized tonic-clonic seizures (GTC) in 78.8% of the patients. Mean age (±SD) at onset was 10.5 ± 3.4 years (range 5–16 years) for absence seizures, 15 ± 3.5 years (range 8–26 years) for myoclonic jerks, and 16 ± 3.5 years (9–28) for GTC. Absence predated myoclonic jerks by 3.9 ± 2.3 years (range-1–9 years) and GTC by 4.4 ± 2.7 years (range 1–8 years) in 14 (21.2%) patients who manifested all three types of seizure. Absence were never antedated by myoclonic jerks or GTC. Myoclonic jerks occurred on awakening in 87.5% of the patients. GTC occurred mainly on awakening, but other patients had nocturnal or diurnal GTC with no circadian distribution. Neurologic examination was normal for all patients except for tremor of the hands similar to essential tremor, noted in 35% of patients. Computed tomography (CT) brain scans were normal: 93% of patients had precipitating factors: sleep deprivation (89.5%), fatigue (73.7%), photosensitivity (36.8%; television and video games 8.8%), menstruation (24.1% of women), mental concentration (22.8%), and stress (12.3%). Incidence of JME among siblings (13 of 41 examined families) implies an autosomal recessive mode of inheritance for this Arab population. EEGs were frequently normal in treated patients. At least one abnormal EEG was recorded in 56 (84.9%) patients. Abnormalities consisted mainly of generalized discharges of spike/double spike and/or polyspike and slow wave. Frequent multiple spikes and discharge fragmentations varied from 0.5to 20-s duration (mean 6.8 s). Twenty (30.3%) had focal abnormalities, and 18 (27.3%) had photoconvulsive discharges. Eighty-eight percent of patients remained seizure-free for 3 years of follow-up. Effective treatment was achieved with valproate (VPA); control of myoclonic jerks was improved with clonazepam (CZP). CZP monotherapy did not consistently prevent GTC. Adding small doses of CZP with simultaneous reduction of VPA was the most effective and better tolerated form of medication, particularly in patients demonstrating an adverse reaction or requiring a large VPA dosage. VPA dosage was successfully reduced in 15 patients who were seizure-free for >2 years and had infrequent seizures before treatment, but 9 of 11 patients relapsed after VPA discontinuation.     

Pharmacological outcomes in newly diagnosed epilepsy

The response to antiepileptic drugs (AEDs) has been examined in 780 adult and adolescent patients with newly diagnosed epilepsy presenting with a range of seizure types and epilepsy syndromes over a 20-year period. Carbamazepine (CBZ, n=312), sodium valproate (VPA, n=315), and lamotrigine (LTG, n=249) were the most common AEDs prescribed as monotherapy. More patients with localization-related epilepsies became seizure free with LTG (63%) than with CBZ (45%, P=0.006) or VPA (42%, P=0.006). For idiopathic generalized epilepsies a greater proportion of patients achieved control with VPA (68%) than with CBZ (31%) or LTG (45%). In particular, more patients with juvenile myoclonic epilepsy responded to VPA (75%) compared with LTG (39%, P=0.014). Seizure freedom was achieved with modest or moderate daily doses (median CBZ 400mg, VPA 1000 mg, (LTG) 150 mg) of all three AEDs in the majority of patients achieving remission. Time to first seizure did not differ among these three drugs when given as first treatment. Adverse effects leading to withdrawal were more frequent with CBZ (16%) than with VPA (7%, P=0.03) or LTG (7%, P=0.018). In patients failing initial monotherapy, response to a combination of two AEDs (27%) was not different from that with alternative monotherapy (32%). The majority of patients with newly diagnosed epilepsy responding to treatment did so rapidly and completely with moderate doses of AEDs, with no differences in time to first seizure.     

Evolution of juvenile myoclonic epilepsy treated from the outset with sodium valproate.

Sodium valproate (VPA) is considered the first choice drug in juvenile myoclonic epilepsy (JME). We have analysed the long-term evolution of 22 patients treated from the outset with VPA. The following inclusion criteria were applied: (1) unequivocal diagnosis of JME; (2) treatment should be initiated with VPA monotherapy; and (3) follow-up for more than 5 years. Twenty-two patients (15 females, seven males) were studied and their EEG recordings were analysed. Their mean age was 28 years (range: 20-40 years) and their mean follow-up was 7.7 years (range: 5-17 years). Four of them suffered persistent seizures despite optimal VPA dosage and needed the addition of a second drug (lamotrigine in three cases, clobazam in one case). All of our patients who continued their treatment are seizure-free. VPA effectively controlled all seizures in 80% of patients. The discontinuation of drug therapy lead to a very high rate of relapses. With accurate diagnosis and appropriate therapy, seizures in JME can be effectively controlled. VPA is a very effective antiepileptic drug in controlling the seizures of JME, but many patients relapse after VPA discontinuation. Thus, JME may require lifelong therapy.     

Do carbamazepine and phenytoin aggravate juvenile myoclonic epilepsy?

BACKGROUND: Juvenile myoclonic epilepsy is a frequent form of idiopathic generalized epilepsy that is usually and easily controlled by valproate monotherapy. However, juvenile myoclonic epilepsy is often misdiagnosed, and some drugs, especially carbamazepine and phenytoin, may have an aggravating effect. OBJECTIVES: To determine the risk of aggravation of juvenile myoclonic epilepsy in patients treated with carbamazepine and phenytoin. METHODS: Among 170 consecutive patients with juvenile myoclonic epilepsy (104 female, 66 male) referred between 1981 and 1998, the authors retrospectively found 40 patients (23%) who had received carbamazepine or phenytoin (duration of epilepsy at referral, 1 to 34 years; mean +/- SD, 13.8 +/- 8.5 years; follow-up, 3 to 50 years; mean +/- SD, 16.4 +/- 11 years). RESULTS: Twenty-three patients (57.5%) experienced aggravation of seizures, whereas 6 (15%) apparently benefited from these drugs. There was no effect in the remaining 11 cases (27.5%). Carbamazepine was prescribed to 28 patients: 19 (68%) had aggravated symptoms, including myoclonic status in two; 4 (14%) were improved, one in association with valproate and one in association with valproate and phenobarbital. Phenytoin was prescribed in 16 cases: 6 (38%) had aggravation and 2 (12%) were improved, including one in association with phenobarbital. Vigabatrin was given in only one case, in association with carbamazepine, and provoked a mixed absence and myoclonic status. CONCLUSIONS: Among commonly prescribed anticonvulsants, carbamazepine appears to have the strongest aggravating potential in patients with juvenile myoclonic epilepsy, whereas the aggravating effect of phenytoin is less prominent. Aggravation was mostly in the form of increased myoclonic jerks.     

Double-blind substitution of vigabatrin and valproate in carbamazepine-resistant partial epilepsy. 012 Study group

Patients from 12 countries reporting two or more partial seizures per month despite treatment with optimal doses of CBZ were randomised to additional vigabatrin (VGB, 2-4 g daily) or sodium valproate (VPA, 1-2 g daily) using a double-blind, double-dummy design. The study included a 6 month retrospective baseline on unchanged CBZ dosage, a month's prospective baseline, a short titration phase, and an assessment period lasting 3 months on duotherapy. CBZ was withdrawn over a further 2 months in responders ( > or = 50% monthly seizure reduction compared with baseline), who continued on alternative monotherapy for 3 or more months. If seizure control deteriorated, CBZ was reinstated and these patients were also followed up for 3 months. A total of 215 patients (108 VGB, 107 VPA) reporting a mean of seven partial seizures per month fulfilled the criteria for the intention-to-treat analysis. 53 and 51% of patients in the VGB and VPA group respectively achieved a monthly reduction in seizure numbers > or = 50%, respectively. 27 and 31% maintained alternative monotherapy. Overall, 17% (7% monotherapy, 10% duotherapy) of the VGB treated patients and 19% (8% monotherapy, 11% duotherapy) of the VPA group remained seizure-free during the final 3 month treatment period. VGB and VPA, which increase neuronal inhibition mediated by gamma aminobutyric acid, can be added to or substituted for CBZ when this Na+ channel blocker fails to control partial seizures. This lends credence to the hypothesis in support of a mechanistic approach to the management of epilepsy.     

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 as first add-on treatment in carbamazepine-resistant epilepsy patients

Numerous clinical reports and several controlled clinical trials have confirmed that vigabatrin is both effective and well-tolerated as an add-on treatment for patients with drug-resistant epilepsy. This report presents the results of a study of 40 patients (22 women and 18 men), aged I960 years (mean 37 years), with partial seizures (with or without secondary generalization) and receiving carbamazepine, 600-1800 mg/day. Vigabatrin was given as first add-on drug at a dose of 2-3 g/day for an average of 6 months, in order to assess the clinical response before considering other anti-epilepsy drugs. There was a significant decrease in seizure frequency, from a median of 13 seizures/month at baseline, to 3 seizures/month during the last month on vigabatrin (p<0.01). Seven patients became seizure-free (17.5%). The most common adverse events experienced during the study were drowsiness, diplopia/blurred vision, and were already present before vigabatrin treatment. In conclusion, vigabatrin is effective as a first add-on therapy for partial epilepsy, refractory to carbamazepine monotherapy, and appears to be a worthy clinical alternative to other drug combinations.     

Monotherapy with Valproate in Primary Generalized Epilepsies

Summary: Sodium valproate enteric-coated tablets were administered as monotherapy to 118 patients (median age, 19 years) with primary generalized epilepsies. More than half (56%) of these patients were transferred from prior drug therapy, most of them because of inadequate seizure control, and some because of adverse effects. Seventy-one percent of the patients experienced tonic-clonic seizures, either alone or in combination with other types of seizures, principally absences. Mean duration of follow-up was 18 months (median, 17 months; range, 1–68 months). At a mean daily dosage of <20 mg/kg, 83% of the patients became seizure-free. Therapy was equally effective against tonic-clonic seizures, absences, and myoclonic seizures. Tonic-clonic seizures were suppressed in 85% of cases (89% when patient had only one seizure type), absences in 82% (95% when patient had only one seizure type), and myoclonic seizures in 82%. Paroxysmal activity was present in 88% of the electroencephalogram (EEG) records before valproate monotherapy, and in 32.4% at the study's end. These results were achieved with generally mild and mostly transient side effects; side effects were reported by 16% of patients during the first month, and 2% at the last follow-up. No hematologic or hepatic toxicity was observed. The lag time between attaining steady-state serum concentrations and achieving maximal clinical improvement suggests that sodium valproate monotherapy should be given an adequate trial to ensure that patients derive the greatest possible benefit before adding or switching to another drug.     

Efficacy and tolerability of antiepileptic drugs in an Omani epileptic population

OBJECTIVE: The aim of this hospital-based study is to get an insight into the efficacy and tolerability of antiepileptic drugs (AED) in Omani epileptic patients. PATIENTS AND METHODS: All Omani patients (aged 14 years and above) suffering from epileptic seizures for at least 2 years and followed-up by board-certified neurologists in Sultan Qaboos University Hospital (SQUH) were evaluated. The treatment retention rate since first visit at SQUH and over the last 2 years was used as primary efficacy measure of AED therapy. Change in seizure-frequency and side effect profiles were also assessed. RESULTS: In this population of 203 confirmed epileptic patients, generalized tonic-clonic (40%) and partial seizures (39%) were most commonly observed, idiopathic/cryptogenic origin (81%) being the most frequent encountered origin. Sixty one percent of the patients were controlled with an AED in monotherapy and overall 34% of patients could be successfully maintained on monotherapy during the whole follow-up period at SQUH (median 6 years). The treatment retention rates for carbamazepine (CBZ) at a daily dose of 400-600 mg, sodium valproate (VPA) at a daily dose of 500-1000 mg, and phenytoin (PHT) at a daily dose of 300 mg, in monotherapy over the total follow-up period was 51, 50, and 21%, respectively. In contrast, over the last 2 years these rates were highest for VPA (91%) followed by CBZ (83%) and PHT (73%). Adverse drug reactions were recorded in 67% of patients, and were most commonly encountered with VPA. CONCLUSIONS: Despite a higher adverse effect profile for VPA, long-term treatment with CBZ and VPA appeared to be equally effective in terms of treatment retention rates and seizure control.