Efficacy and tolerability of the new antiepileptic drugs I: treatment of new onset epilepsy: report of the Therapeutics and Technology Assessment Subcommittee and Quality Standards Subcommittee of the American Academy of Neurology and the American Epilepsy Society

OBJECTIVE

To assess the evidence demonstrating efficacy, tolerability, and safety of seven new antiepileptic drugs (AEDs) (gabapentin, lamotrigine, topiramate, tiagabine, oxcarbazepine, levetiracetam, and zonisamide-reviewed in the order in which these agents received approval by the US Food and Drug Administration) in the treatment of children and adults with newly diagnosed partial and generalized epilepsies.

METHODS

A 23-member committee, including general neurologists, pediatric neurologists, epileptologists, and doctors in pharmacy, evaluated the available evidence based on a structured literature review including MEDLINE, Current Contents, and Cochrane library for relevant articles from 1987 until September 2002, with selected manual searches up until 2003.

RESULTS

There is evidence either from comparative or dose-controlled trials that gabapentin, lamotrigine, topiramate, and oxcarbazepine have efficacy as monotherapy in newly diagnosed adolescents and adults with either partial or mixed seizure disorders. There is also evidence that lamotrigine is effective for newly diagnosed absence seizures in children. Evidence for effectiveness of the new AEDs in newly diagnosed patients with other generalized epilepsy syndromes is lacking.

CONCLUSIONS

The results of this evidence-based assessment provide guidelines for the prescription of AEDs for patients with newly diagnosed epilepsy and identify those seizure types and syndromes where more evidence is necessary.

Efficacy and tolerability of the new antiepileptic drugs II: Treatment of refractory epilepsy: Report of the Therapeutics and Technology Assessment Subcommittee and Quality Standards Subcommittee of the American Academy of Neurology and the American Epilepsy Society

OBJECTIVE

To assess the evidence demonstrating efficacy, tolerability, and safety of seven new antiepileptic drugs (AEDs) (gabapentin, lamotrigine, topiramate, tiagabine, oxcarbazepine, levetiracetam, and zonisamide) in the treatment of children and adults with refractory partial and generalized epilepsies.

METHODS

A 23-member committee including general neurologists, pediatric neurologists, epileptologists, and doctors in pharmacy evaluated the available evidence based on a structured literature review including MEDLINE, Current Contents, and Cochrane library for relevant articles from 1987 until March 2003.

RESULTS

All of the new AEDs were found to be appropriate for adjunctive treatment of refractory partial seizures in adults. Gabapentin can be effective for the treatment of mixed seizure disorders, and gabapentin, lamotrigine, oxcarbazepine, and topiramate for the treatment of refractory partial seizures in children. Limited evidence suggests that lamotrigine and topiramate are also effective for adjunctive treatment of idiopathic generalized epilepsy in adults and children, as well as treatment of the Lennox Gastaut syndrome.

CONCLUSIONS

The choice of AED depends upon seizure and/or syndrome type, patient age, concomitant medications, AED tolerability, safety, and efficacy. The results of this evidence-based assessment provide guidelines for the prescription of AEDs for patients with refractory epilepsy and identify those seizure types and syndromes where more evidence is necessary.

Vagus nerve stimulation therapy for epilepsy in older adults

The authors assessed the efficacy, safety, and tolerability of vagus nerve stimulation (VNS) for refractory epilepsy in 45 adults 50 years of age and older. They determined seizure frequency, adverse effects, and quality of life. At 3 months, 12 patients had a >50% decrease in seizure frequency; at 1 year, 21 of 31 studied individuals had a >50% seizure decrease. Side effects were mild and transient. Quality of life scores improved significantly with time.

Assessing the Winning Teams program of interactive satellite-based training

This research assessed an interactive satellite-based training program integrating interactive audiovisual experiences with face-to-face interactions. Key elements were content created by experts, high-quality video segments, satellite-based interaction, off-line interactions among teams of parents and caregivers, workshops, and team building exercises. For pragmatic reasons, it was necessary to develop brief assessment instruments concurrently with training. A large set of survey items were created from draft materials and reduced empirically through piloting to those with the best psychometric properties. To avoid the appearance of traditional testing, knowledge was assessed with Likert items. Surveys measured participant satisfaction, knowledge, attitudes, and the application and articulation of concepts. Participant satisfaction was high. Participants increased positive attitudes and learned appropriate vocabulary. Training was more effective than no training or watching videotapes. The program appears to represent a viable model of training that could successfully be applied to Internet technologies.

Landau-Kleffner syndrome. Treatment with subpial intracortical transection

Landau-Kleffner syndrome (LKS) is an acquired epileptic aphasia occurring in childhood and associated with a generally poor prognosis for recovery of speech. It is thought to be the result of an epileptogenic lesion arising in speech cortex during a critical period of development. Utilizing a new surgical technique designed to eliminate the capacity of cortical tissue to generate seizures while preserving the normal cortical physiological function, we have treated 14 children with aphasia, seizures and a severely abnormal EEG by multiple subpial transection of the epileptogenic cortex. Seven of the 14 patients (50%) have recovered age-appropriate speech, are in regular classes in school and no longer require speech therapy. Four of the 14 (29%) have shown marked improvement, are speaking and understanding verbal instruction but are still receiving speech therapy. Thus, 11 of the 14 (79%), none of whom had used language to communicate for at least 2 years, are now speaking--a rate of sustained improvement considered unusual in this disorder. This study documents the value of a treatment modality not previously used in LKS. Success depends on selection of cases having severe epileptogenic abnormality that can be demonstrated to be unilateral in origin despite a bilateral electrographic manifestation.

Tailored anterior temporal lobectomy. Relation between extent of resection of mesial structures and postsurgical seizure outcome

OBJECTIVE

The purpose of this study was to assess the relationship between the extent of resection of mesial temporal structures and postsurgical seizure outcome in a group of patients who had undergone a tailored anterior temporal lobectomy.

METHODS

Twenty-four patients with unilateral interictal and ictal foci restricted to anterior/mesial temporal regions underwent resection of mesial and temporal lateral structures, the extent of which was tailored by intraoperative electrocorticographic findings and functional mapping of eloquent cortex. The extent of resection was determined with postoperative magnetic resonance imaging scans, using a semiquantitative method, based on a 20-compartment model of the temporal lobe. The magnetic resonance imaging scans were rated by three investigators blinded to seizure outcome. Follow-up period ranged between 18 months and 5 years.

RESULTS

Amygdala and hippocampus were spared in six patients; nine patients had a partial to total resection of amygdala, eight patients had a resection of amygdala and the anterior third of the hippocampus, and one patient underwent resection of amygdala and anterior two thirds of hippocampus. Twenty-one of the 24 patients were seizure free (Engel's class I) and three had rare seizures (Engel's class II). Among these three patients, one had a resection of amygdala; one had resection of amygdala and anterior third of hippocampus; while in the third patient, mesial structures were spared.

CONCLUSION

These data suggest that in patients with an anterotemporal seizure focus, the sparing or limited resection of amygdala and/or hippocampus is not necessarily associated with a poor seizure outcome, as had been previously suggested, provided that the decision not to resect is based on the absence of epileptiform activity during intraoperative electrocorticography or during recordings with depth electrodes.

Vagus nerve stimulation for treatment of partial seizures: 3. Long-term follow-up on first 67 patients exiting a controlled study. First International Vagus Nerve Stimulation Study Group

Vagus nerve stimulation (VNS) has demonstrated a significant anticonvulsant effect in preclinical studies, in pilot studies in humans, and in the acute phase of a multicenter, double-blinded, randomized study. After completion of a 14-week, blinded, randomized study, with 31 receiving high (therapeutic) VNS and 36 receiving low (less or noneffective) VNS, 67 patients elected to continue in an open extension phase. During the extension phase, all 67 patients received high VNS. Seizure frequency during the 3-month treatment blocks was compared with a 12-week baseline. For both groups, all periods of high VNS demonstrated a significant decrease in seizure frequency (p < 0.01 level) as compared with baseline. For the 16-18-month period of VNS, data were available for 26 of the 31 patients randomized to high VNS. This group achieved a 52.0% mean seizure frequency percentage reduction as compared with baseline. For those converted from low to high VNS, data were available for 24 of the 36 patients at the 16-18-month time period. This group reported a mean seizure frequency percentage reduction of 38.1% as compared with baseline. No significant change in the safety/side effect profile was reported during long-term follow-up. The previously reported side effects of hoarseness/voice change, coughing, and paresthesia (sensation in neck and jaw) continued to occur during VNS. These side effects were well tolerated. During the follow-up period, 1 patient died of thrombotic thrombocytopenic purpura (TTP) and 5 patients discontinued treatment because of unsatisfactory efficacy.

Placebo-controlled study of the efficacy and safety of lamotrigine in patients with partial seizures. U.S. Lamotrigine Protocol 0.5 Clinical Trial Group

We evaluated the efficacy and safety of lamotrigine (300 and 500 mg/day) as add-on therapy in a multicenter, randomized, double-blind, parallel-group, placebo-controlled study of 216 patients with refractory partial seizures. During 6 months of treatment, median seizure frequency decreased by 8% with placebo, 20% with 300 mg lamotrigine, and 36% with 500 mg lamotrigine. Seizure frequency decreased by > or = 50% in one-third of the 500-mg group and one-fifth of the 300-mg group. Reductions in seizure frequency and seizure days were statistically significant, compared with placebo, for the 500-mg group but not the 300-mg group. Most adverse events were minor and resolved over time. Nine percent of patients on lamotrigine withdrew because of adverse experiences. Lamotrigine plasma concentrations appeared to be a linear function of dose, and the drug did not affect plasma concentrations of concomitant antiepileptic drugs. Lamotrigine was safe, effective, and well tolerated as add-on therapy for refractory partial seizures.

Weeping as a common element of pseudoseizures

Weeping is an extremely rare ictal phenomenon. We report weeping during or at the very end of electrographically proved pseudoseizures in 10 patients. We conclude that weeping is a relatively common and specific clinical feature of pseudoepileptic seizures.

Reduction of sexual activities in females taking antiepileptic drugs

Studies of male or sexually unspecified populations have revealed loss of libido and decreased sexual function in patients with epilepsy taking antiepileptic drugs. The relative contributions of antiepileptic drugs, seizures, brain injury, and social factors have not been clearly delineated. We studied sexual activity in a group of females taking antiepileptic drugs, and defined a subgroup with pronounced hyposexuality.

Correlation of abnormalities of interictal n-isopropyl-p-iodoamphetamine single-photon emission tomography with focus of seizure onset in complex partial seizure disorders

Single-photon emission tomography (SPECT) scanning with n-isopropyl-p-iodoamphetamine (IMP) was performed on 23 patients with complex partial seizures undergoing long-term video electroencephalographic (EEG) seizure monitoring. Twenty-one of the 23 patients had abnormalities on SPECT scanning consisting of areas of decreased activity reflecting diminished cerebral blood flow. In 15 of these 21 patients, there was good correlation between the site of the abnormality on SPECT scan and the site of origin of seizures monitored by EEG. Of the six remaining patients, four had multifocal SPECT abnormalities, with one of the abnormal areas corresponding with an ictal site. The two remaining patients had SPECT abnormalities and major ictal EEG foci in entirely different areas. In contrast to the high proportion of abnormal SPECT scans, only 10 of 23 focal abnormalities were discovered on magnetic resonance imaging (MRI) scans. Three patients who had seizures within 2 h of an initial scan were rescanned 4-5 h after injection. Focal areas of increased blood flow were noted on all three scans, although not always at the ictal site. The SPECT scan appears to be useful in interictal localization of seizure foci. Postictal scans may also be useful, although our numbers are too small to draw conclusions.

Magnetic resonance imaging as a sensitive and specific predictor of neoplasms removed for intractable epilepsy

Twenty-three patients had magnetic resonance imaging (MRI) and computed tomography (CT) of the head prior to surgery for medically intractable epilepsy. Eleven patients had neoplasms, mostly astrocytomas. Six of the 11 tumors were seen on CT. In five of the six cases, the MRI showed a focal area of increased signal on T2-weighted images. All 11 tumors were detected by MRI. None of the non-neoplastic lesions produced an abnormal T2-weighted signal area on MRI. Only one of the non-neoplastic lesions was seen on both CT and on MRI. MRI allowed clear discrimination between tumors and non-neoplastic lesions in patients coming to surgery for intractable epilepsy.

Prevalence of psychologic disorders after surgical treatment of seizures

To investigate whether surgical treatment of refractory epilepsy is associated with increased risk for serious psychopathology, 25 treated patients were compared with 25 current candidates for surgery matched on demographic and neuroepileptic characteristics. Diagnoses were made by the National Institute of Mental Health Diagnostic Interview Schedule. No differences between groups in lifetime or point prevalence rates were significant. The rate of psychosis in the postoperative group (8%) approximated the lower estimates in previous studies. Thus, surgical treatment of seizures did not increase the risk for psychopathology. However, patients with temporal lobe electroencephalogram foci or tumor as the epileptogenic lesion were more likely to have serious disorders than other patients. Also, anxiety disorders were more prevalent in our patient groups than in the general population.

Infarction after surgery for focal epilepsy: manipulation hemiplegia revisited

The success of surgery for seizure focus resection depends on postoperative reduction or disappearance in number of seizures, improvement in psychosocial functioning, and low morbidity and mortality. Permanent neurologic sequelae are most often not discussed in this context. Deficits more than a superior quadrantanopsia are not expected after temporal lobectomy. Four cases of ischemic stroke after seizure focus resection, each distant from the site of tissue removal, are reported. These are the first such radiologically documented reports of "manipulation hemiplegia." The permanent neurologic deficits are not attributed to resected tissue or edema.

Hemispheric asymmetry of visual evoked potentials in patients with well-defined occipital lesions

Visual evoked potentials were examined in 3 patients who had well defined unilateral occipital lobectomy. In an attempt to resolve discrepancies in the interpretation of hemispheric asymmetries in evoked potentials, recordings were obtained from a wide array of electrodes with multiple montages during full-field and hemi-field stimulation with checkerboard pattern reversal and during full-field flash stimulation. The discrepancies appear to be due primarily to differences in electrode montages used in recording. The use of a midfrontal reference electrode reliably produces a paradoxical EP lateralization: abnormal EPs are recorded over the intact occipital lobe and normal EPs are recorded over the ablated occipital lobe. These findings are fully consistent with the interpretation of Barrett et al. (1976) that the generator of the P100 has an equivalent dipole located in the calcarine cortex on the posteromedial surface of the contralateral hemisphere. Our findings support the use of the Queen Square montage (Halliday et al. 1977). The use of electrodes at O1 and O2 referred to the ipsilateral earlobe yields inconsistent lateralization and should be discouraged. The lateralization of EP abnormalities did not differ for flash and pattern reversal, although the asymmetries were sometimes more prominent with pattern reversal.

Localized hirsutism following Colle's fracture

Images

The electroencephalogram in Tourette syndrome

The electroencephalogram (EEG) was studied in 38 patients with Tourette syndrome. Psychometric tests and neurological evaluation identified patients with signs of additional central nervous system dysfunction. Thirteen patients (34%) had some EEG abnormality. In contrast to findings by other investigators, epileptiform activity was uncommon (only 2 out of 38). Most of the patients with EEG abnormalities either had other objective signs of neurological dysfunction or were taking haloperidol, a drug known to disturb the EEG.

Cerebral atrophy, EEG slowing age, education, and cognitive functioning in suspected dementia

Seventy-eight hospital patients, 50 years of age or older, were selected for suspected changes in mentation and for the absence of focal or other organic brain disease. They were studied in relation to education, age, cerebral atrophy (by computerized tomography), electroencephalographic (EEG) slowing, and performance in several neuropsychologic tests. Adequate test-retest reliability of the cognitive measures and interjudge reliability of the cerebral atrophy and EEG measures were demonstrated. Stepwise multiple regression analyses suggested the following: (1) EEG slowing is the strongest and most general pathologic influence on cognition in elderly persons without overt brain disease. (2) Cerebral atrophy independently affects primarily the verbal recall of recent and remote information. (3) Age independently affects primarily recent memory for both verbal and nonverbal material. (4) Formal education is a powerful influence that must be accounted for in all studies of the effects of age on cognition.

Treatment and prognosis of hemiballismus

Acute hemiballismus due to a cerebrovascular lesion may have a grave prognosis. In the past nine years, we have treated 11 patients who had an acute onset of hemiballismus believed to be the result of an acute vascular lesion with neuroleptic drugs (most frequently haloperidol). None of the 11 died, and the movement disorders were greatly reduced or eliminated. In eight patients the drugs were withdrawn within six months, without recurrence of the movement disorders. Spinal-fluid homovanillic acid levels were increased in three patients, suggesting that altered dopaminergic feedback mechanisms may be involved in the pathophysiology of hemiballismus. Our observations suggest that the prognosis of hemiballismus is not necessarily as grave as has been believed, and that neuroleptic therapy may alter the outcome of this disorder.

Movement phosphenes in optic neuritis: a new clinical sign

Positive visual phenomena (phosphenes) elicited by eye movements have been described in normal individuals and in myopes with vitreous opacities. In the present paper we describe eye movement-induced phosphenes that appear to be related to optic nerve involvement in patients with optic neuritis and multiple sclerosis. This phenomenon is not associated with vitreous or retinal defects, nor is it similar to phosphenes observed in normal individuals. Instead, it shares many characteristics with the well-known Lhermitte sign and is believed to represent a similar phenomenon.

Correlation between diffuse EEG abnormalities and cerebral atrophy in senile dementia

Thirty-five elderly patients were investigated because of clinical signs of dementia. The presence or diffuse cerebral atrophy, and its severity, were determined by the use of computed tomography (CT scan). All of the patients were also examined by electroencephalography (EEG), and the presence of diffuse abnormalities, especially diffuse slowing, was noted. Specifically, patients with normal or near-normal EEGs were compared with those with severe diffuse slowing. No correlation between the presence or severity of diffuse EEG abnormalities and the degree of cerebral atrophy as measured by CT scan was found. Though the EEG is clearly identifying physiological dysfunction of nerve cells in demented patients it does not appear to be reliable tool for the prediction of diffuse cerebral atrophy in this population.

Levodopa-induced myoclonus

Twelve parkinsonian patients on long-term levodopa therapy developed intermittent, myoclonic body jerks. The movements consisted of single unilateral or bilateral abrupt jerks of the extremities and occurred most frequently during sleep. Although directly related to daily dosage of levodopa, the myoclonus was specifically blocked by the serotonin antagonist, methysergide. Levodopa-induced myoclonus may be related to intermittent increases of activity of serotonin in the brain and results from levodopa-induced dysregulation of serotonin activity.

Deanol in the treatment of levodopa-induced dyskinesias

Levodopa-induced dyskinesias frequently limit the clinical efficacy of levodopa therapy in Parkinson's disease. Deanol recently has been reported to be of value in relieving the dyskinesias by acting through a central cholinergic mechanism. Seventeen outpatients with levodopa-induced dyskinesias were given deanol in dosages of 300 to 900 mg per day. The dyskinesias improved in four of the patients, remained unchanged in five, and worsened in eight. In all four patients who showed improvement after institution of deanol therapy, the improvement continued after the patients were switched to a placebo. One of these patients also demonstrated improvement in his parkinsonism, while two others experienced a worsening in their parkinsonism. Deanol does not appear to be effective in the treatment of levodopa-induced dyskinesias.

Prolonged drug-induced Parkinsonism

Three non-schizophrenic individuals with drug-induced parkinsonism of a prolonged nature were presented. This is the first report of the occurrence of this extrapyramidal side effect in patients without a diagnosis of psychosis and demonstrates that neuroleptic-induced parkinsonism can occur in such individuals. The prolonged nature of the disability following withdrawal was unusual. Although such occurrences have been previously reported, no long-term study of the natural history of this syndrome has been reported. This study suggests that neuroleptic-induced parkinsonism can last at least 18 months and still disappear completely. This is possibly related to the long persistence of neuroleptic agents within the body.