Neuropsychological Performance 1 Year After Status Epilepticus in Adults

OBJECTIVES

Status epilepticus (SE) may lead to or worsen cognitive dysfunction. Few studies have evaluated magnitude and profile of cognitive dysfunction in patients after SE. Characterization of cognitive deficits may be important for rehabilitation and follow-up. We assessed cognitive function in a consecutive, non-selected group of relatively healthy survivors with a comprehensive neuropsychological test battery.

METHODS

A total of 33 patients (24 men, 9 women; mean age 54,9 years, mean education 11,8 years) were tested 1 year after SE with Wechsler Adult Intelligence Scale Fourth edition (WAIS-IV), Rey Auditory Verbal Learning Test, subtests from the Wechsler Memory Scale-Revised, Phonemic and Semantic word list generation, and the Halstead-Reitan Battery. Premorbid IQ was estimated with a Norwegian version of the National Adult Reading Test (NART). Results were compared to published norms. Regression analyses and independent groups t-tests were performed to assess the influence of background variables.

RESULTS

Mean performance generally was about one standard deviation below average. Full scale IQ (WAIS-IV) was significantly reduced compared to estimated premorbid IQ (NART). Negative influence on cognition of brain lesions visible on computed tomography or magnetic resonance imaging and duration of SE >30 min was shown by group comparisons.

CONCLUSIONS

SE represents a marker for possible cognitive dysfunction, and follow-up with neuropsychological assessment and cognitive rehabilitation seems warranted in most patients. Complex problem-solving abilities with high general sensitivity to brain impairment showed the most prominent reduction. Otherwise, no specific profile of domain affection was found. Structural brain lesions and duration of SE over 30 min represent risk factors for cognitive deficit.

Codeine is associated with poor prognosis in acute stroke

BACKGROUND

The aim of this study was to investigate how the use of analgesics, sleeping drugs, and sedatives relates to prognosis and complications in stroke patients in the acute care phase (≤48 hr) after a stroke.

MATERIALS AND METHODS

Patients with ischemic stroke, hemorrhagic stroke, and transient ischemic attack were included. The study is based on gathering of data on medication from 921 patient records belonging to patients included in the Bergen NORSTROKE registry, 12.2009-02.2012. In this database risk factors, stroke severity, etiology, and blood analyses were prospectively registered. We have retrospectively registered if patients received one drug or more from a list of analgesics, sleeping drugs, and sedatives within the first 48 hr after admission.

RESULTS

In total, 921 patients were included in the study, 408 females and 513 males. Mean age was 71.0 years. In total, 101 patients were given sleeping drugs, 97 patients sedatives and 140 patients analgesics. Of the group given analgesics, 90 patients were given codeine-containing analgesics. Logistic regression analyses showed that codeine-containing analgesics were associated with an increased occurrence of pneumonia (OR = 3.8, p < .001), stroke worsening (OR = 2.7, p = .001), and a higher mRS-score (OR = 2, p = .024) day 7. The study did not show any relation between poorer prognosis or increased occurrence of complications and the use of other analgesics, sedatives and/or sleeping drugs.

CONCLUSION

Use of codeine-containing analgesics is associated with a poorer short-term prognosis and an increased occurrence of complications in the acute phase after a stroke. The highly significant findings suggest that codeine has a negative effect on acute stroke patients. The study reflects exploratory analyses and prospective studies are necessary to determine the background of the association observed in our study.

Myoclonus epilepsy and ataxia due to KCNC1 mutation: Analysis of 20 cases and K+ channel properties

OBJECTIVE

To comprehensively describe the new syndrome of myoclonus epilepsy and ataxia due to potassium channel mutation (MEAK), including cellular electrophysiological characterization of observed clinical improvement with fever.

METHODS

We analyzed clinical, electroclinical, and neuroimaging data for 20 patients with MEAK due to recurrent KCNC1 p.R320H mutation. In vitro electrophysiological studies were conducted using whole cell patch-clamp to explore biophysical properties of wild-type and mutant K_V 3.1 channels.

RESULTS

Symptoms began at between 3 and 15 years of age (median = 9.5), with progressively severe myoclonus and rare tonic-clonic seizures. Ataxia was present early, but quickly became overshadowed by myoclonus; 10 patients were wheelchair-bound by their late teenage years. Mild cognitive decline occurred in half. Early death was not observed. Electroencephalogram (EEG) showed generalized spike and polyspike wave discharges, with documented photosensitivity in most. Polygraphic EEG-electromyographic studies demonstrated a cortical origin for myoclonus and striking coactivation of agonist and antagonist muscles. Magnetic resonance imaging revealed symmetrical cerebellar atrophy, which appeared progressive, and a prominent corpus callosum. Unexpectedly, transient clinical improvement with fever was noted in 6 patients. To explore this, we performed high-temperature in vitro recordings. At elevated temperatures, there was a robust leftward shift in activation of wild-type K_V 3.1, increasing channel availability.

INTERPRETATION

MEAK has a relatively homogeneous presentation, resembling Unverricht-Lundborg disease, despite the genetic and biological basis being quite different. A remarkable improvement with fever may be explained by the temperature-dependent leftward shift in activation of wild-type K_V 3.1 subunit-containing channels, which would counter the loss of function observed for mutant channels, highlighting KCNC1 as a potential target for precision therapeutics. Ann Neurol 2017;81:677-689.

Neuroleptic malignant syndrome: an easily overlooked neurologic emergency

Neuroleptic malignant syndrome is an unpredictable iatrogenic neurologic emergency condition, mainly arising as an idiosyncratic reaction to antipsychotic agent use. It is characterized by distinctive clinical features including a change in mental status, generalized rigidity, hyperpyrexia, and dysautonomia. It can be lethal if not diagnosed and treated properly. Mortality and morbidity attributed to this syndrome have recently declined markedly due to greater awareness, earlier diagnosis, and intensive care intervention. In most cases, the syndrome occurs as a result of a rapid increase in a dose of neuroleptic, especially one of the long-acting ones. Pathophysiology behind this syndrome is attributed to a dopamine receptor blockade inside the neurons rendered by the offending drug and excessive calcium release from the sarcoplasmic reticulum of skeletal myocytes. Laboratory tests, although not diagnostic, may assist in assessing the severity of the syndrome and also the consequent complications. The syndrome has been described in all age groups and occurs more in males than in females. Genetics appears to be central regarding the etiology of the syndrome. Stopping the use of the offending agent, cold intravenous fluids, and removal of the causative agent and its possible active metabolites is the cornerstone of treatment. Periodic observation of psychotic patients recently started on antipsychotic medications, especially those being treated with depot preparations, may aid to an early diagnosis of the syndrome and lead to early treatment.

Life satisfaction in women with epilepsy during and after pregnancy

OBJECTIVE

The aim of this study was to investigate life satisfaction in women with epilepsy during and after pregnancy.

METHODS

The study was based on the Norwegian Mother and Child Cohort Study, including 102,265 women with and without epilepsy from the general population. Investigation took place at pregnancy weeks 15-19 and 6 and 18months postpartum. Women with epilepsy were compared with a reference group without epilepsy.

RESULTS

The proportion of women with epilepsy was 0.6-0.7% at all three time points. Women with epilepsy reported lower life satisfaction and self-esteem both during and after pregnancy compared with the references. Single parenting correlated negatively with life satisfaction in epilepsy during the whole study period. Epilepsy was associated with lower levels of relationship satisfaction and higher levels of work strain during pregnancy and lower levels of self-efficacy and satisfactory somatic health 18months postpartum. Adverse life events, such as divorce, were more common in women with epilepsy compared with the references, and fewer women with epilepsy had a paid job 18months postpartum.

SIGNIFICANCE

Reduced life satisfaction associated with epilepsy during and after pregnancy showed that, even in a highly developed welfare society, women with epilepsy struggle. Mothers with epilepsy and their partners should be examined for emotional complaints and partnership satisfaction during and after pregnancy. Validated screening tools are available for such measures.

Psychiatric Comorbidity, Social Aspects and Quality of Life in a Population-Based Cohort of Expecting Fathers with Epilepsy

OBJECTIVES

To investigate psychiatric disorders, adverse social aspects and quality of life in men with epilepsy during partner's pregnancy.

METHOD

We used data from the Norwegian Mother and Child Cohort Study, including 76,335 men with pregnant partners. Men with epilepsy were compared to men without epilepsy, and to men with non-neurological chronic diseases.

RESULTS

Expecting fathers in 658 pregnancies (mean age 31.8 years) reported a history of epilepsy, 36.9% using antiepileptic drugs (AEDs) at the onset of pregnancy. Symptoms of anxiety or depression were increased in epilepsy (7.0% and 3.9%, respectively) vs. non-epilepsy (4.6% and 2.5%, respectively, p = 0.004 and 0.023), and so were new onset symptoms of depression (2.0% vs. 1.0%, p < 0.031) and anxiety (4.3% vs. 2.3%, p = 0.023). Low self-esteem (2.5%) and low satisfaction with life (1.7%) were more frequent among fathers with epilepsy compared to fathers without epilepsy (1.3% and 0.7%, respectively, p = 0.01 and 0.010). Adverse social aspects and life events were associated with epilepsy vs. both reference groups. Self-reported diagnoses of ADHD (2.2%) and bipolar disorder (1.8%) were more common in epilepsy vs. non-epilepsy (0.4% and 0.3%, respectively, p = 0.002 and 0.003) and non-neurological chronic disorders (0.5% and 0.5%, respectively, p = 0.004 and 0.018). A screening tool for ADHD symptoms revealed a higher rate compared to self-reported ADHD (9.5% vs. 2.2%, p < 0.001).

CONCLUSION

Expecting fathers with epilepsy are at high risk of depression and anxiety, adverse socioeconomic aspects, low self-esteem, and low satisfaction with life. Focus on mental health in fathers with epilepsy during and after pregnancy is important. The use of screening tools can be particularly useful to identify those at risk.

A recurrent de novo mutation in KCNC1 causes progressive myoclonus epilepsy

Progressive myoclonus epilepsies (PMEs) are a group of rare, inherited disorders manifesting with action myoclonus, tonic-clonic seizures and ataxia. We sequenced the exomes of 84 unrelated individuals with PME of unknown cause and molecularly solved 26 cases (31%). Remarkably, a recurrent de novo mutation, c.959G>A (p.Arg320His), in KCNC1 was identified as a new major cause for PME. Eleven unrelated exome-sequenced (13%) and two affected individuals in a secondary cohort (7%) had this mutation. KCNC1 encodes KV3.1, a subunit of the KV3 voltage-gated potassium ion channels, which are major determinants of high-frequency neuronal firing. Functional analysis of the Arg320His mutant channel showed a dominant-negative loss-of-function effect. Ten cases had pathogenic mutations in known PME-associated genes (NEU1, NHLRC1, AFG3L2, EPM2A, CLN6 and SERPINI1). Identification of mutations in PRNP, SACS and TBC1D24 expand their phenotypic spectra to PME. These findings provide insights into the molecular genetic basis of PME and show the role of de novo mutations in this disease entity.

Fetal growth restriction and birth defects with newer and older antiepileptic drugs during pregnancy

The primary aim of this study was to assess the risks of fetal growth restriction and birth defects in children exposed prenatally to newer and older antiepileptic drugs, using an unselected epilepsy cohort. Deliveries recorded in the compulsory Medical Birth Registry of Norway 1999-2011 formed the study population. All 2,600 children exposed to antiepileptic drugs during pregnancy were compared to all 771,412 unexposed children born to women without epilepsy. Children of untreated mothers with epilepsy served as an internal control group. The main outcomes were small for gestational age birth weight and head circumference, and major congenital malformations. Children exposed to antiepileptic drugs had a moderate risk of growth restriction. Infants exposed to topiramate had a considerable risk of microcephaly (11.4 vs. 2.4 %; OR 4.8; CI 2.5-9.3) and small for gestational age birth weight (24.4 vs. 8.9 %; OR 3.1; 95 % CI 1.9-5.3). Carbamazepine, lamotrigine, levetiracetam, oxcarbazepine, gabapentin, and pregabalin had low malformation rates, whereas topiramate tended to have an elevated malformation rate. Valproate monotherapy was associated with a significant risk of birth defects (6.3 vs. 2.9 %; OR 2.5; CI 1.6-3.8), and specifically with septal heart defects and hypospadias. For mothers using valproate, the presence of major birth defect in one child was associated with a markedly increased risk for the siblings (42.9 vs. 6.7 %; OR 10.4; CI 2.3-46.7). Children of untreated mothers with epilepsy had malformation risk similar to the reference group. In conclusion, topiramate was associated with a substantial risk of fetal growth restriction, and possibly an increased malformation rate. Other newer-generation antiepileptic drugs had a low malformation rate. Valproate monotherapy had a significant malformation risk, especially in repeated pregnancies.

Early child development and exposure to antiepileptic drugs prenatally and through breastfeeding: a prospective cohort study on children of women with epilepsy

IMPORTANCE

Exposure to antiepileptic drugs during pregnancy is associated with adverse effects on psychomotor development.

OBJECTIVES

To determine whether signs of impaired development appear already during the first months of life in children exposed prenatally to antiepileptic drugs, and to explore potential adverse effects of antiepileptic drug exposure through breastfeeding.

DESIGN, SETTING, AND PARTICIPANTS

Mothers at 13 to 17 weeks of pregnancy were recruited in the population-based, prospective Norwegian Mother and Child Cohort Study from 1999 to 2009. The mothers reported on their child's motor and social skills, language, and behavior using items from standardized screening tools at 6 months (n = 78,744), 18 months (n = 61,351), and 36 months (n = 44,147) of age. The mothers also provided detailed information on breastfeeding during the first year. MAIN OUTCOMES AND MEASURES The risk of adverse development in children according to maternal or paternal epilepsy was estimated as the odds ratio with corresponding 95% confidence interval, adjusted for maternal age, parity, education, smoking, breastfeeding, depression/anxiety, folate supplementation, and congenital malformation in the child.

RESULTS

At age 6 months, infants of mothers using antiepileptic drugs (n = 223) had a higher risk of impaired fine motor skills compared with the reference group (11.5% vs 4.8%, respectively; odds ratio = 2.1; 95% CI, 1.3-3.2). Use of multiple antiepileptic drugs compared with the reference group was associated with adverse outcome for both fine motor skills (25.0% vs 4.8%, respectively; odds ratio = 4.3; 95% CI, 2.0-9.1) and social skills (22.5% vs 10.2%, respectively; odds ratio = 2.6; 95% CI, 1.2-5.5). Continuous breastfeeding in children of women using antiepileptic drugs was associated with less impaired development at ages 6 and 18 months compared with those with no breastfeeding or breastfeeding for less than 6 months. At 36 months, prenatal antiepileptic drug exposure was associated with adverse development regardless of breastfeeding status during the first year. Children of women with epilepsy who did not use antiepileptic drugs and children of fathers with epilepsy had normal development at 6 months.

CONCLUSIONS AND RELEVANCE

Prenatal exposure to antiepileptic drugs was associated with impaired fine motor skills already at age 6 months, especially when the child was exposed to multiple drugs. There were no harmful effects of breastfeeding. Women with epilepsy should be encouraged to breastfeed their children irrespective of antiepileptic drug treatment.

Psychiatric comorbidity and social aspects in pregnant women with epilepsy - the Norwegian Mother and Child Cohort Study

OBJECTIVE

The objective of this study was to investigate psychiatric disease and social aspects in young women with epilepsy before and during pregnancy.

METHOD

The study included self-reported data from 106,935 pregnancies.

RESULTS

Seven hundred eleven women reported having epilepsy, and 45.9% of them were using antiepileptic drugs (AEDs). Compared to the reference group, self-reported eating disorders and depression were increased in the untreated epilepsy group before pregnancy. Both AED-treated and untreated women with epilepsy reported higher depression scores as assessed by the Hopkins Symptom Checklist, and the Lifetime Major Depression scale was increased in AED-treated women. Antiepileptic drug treatment was linked to low income (27.4% vs. 18.4%, p<0.001) and no income (5.5% vs. 2.6%, p=0.001). Low educational level was associated with epilepsy in AED-treated and untreated women (50.5%, p<0.001 and 46.9%, p<0.001 vs. 32.2%), as was unemployment due to disability (7.9%, p<0.001 and 6.5%, p<0.001 vs. 1.5%) and single parenting (4.4%, p=0.016 and 4.5%, p=0.007 vs. 2.4%). No difference was found for smoking, alcohol use, or narcotic use.

CONCLUSION

Symptoms of depression were associated with epilepsy both during and before pregnancy. Epilepsy was linked to eating disorders before pregnancy. Unemployment, single parenting, and low educational level were linked to epilepsy in young pregnant females. Efforts aiming at treatment and screening for psychiatric comorbidity in pregnant women with epilepsy are important in the follow-up of these patients.

Exposure to antiepileptic drugs in utero and child development: a prospective population-based study

PURPOSE

Antiepileptic drugs may cause congenital malformations. Less is known about the effect on development in infancy and childhood. The aim of this study was to examine whether exposure to antiepileptic drugs during pregnancy has an effect on early child development.

METHODS

From mid-1999 through December 2008, children of mothers recruited at 13-17 weeks of pregnancy were studied in the ongoing prospective Norwegian Mother and Child Cohort Study. Information on birth outcomes were obtained from the Medical Birth Registry (108,264 children), and mothers reported on their child's motor development, language, social skills, and autistic traits using items from standardized screening tools at 18 months (61,351 children) and 36 months (44,147 children) of age. The relative risk of adverse outcomes in children according to maternal or paternal epilepsy with and without prenatal exposure to antiepileptic drugs was estimated as odds ratios (ORs), using logistic regression with adjustment for maternal age, parity, education, smoking, depression/anxiety, folate supplementation, and child congenital malformation or low birth weight.

KEY FINDINGS

A total of 333 children were exposed to antiepileptic drugs in utero. At 18 months, the exposed children had increased risk of abnormal scores for gross motor skills (7.1% vs. 2.9%; OR 2.0, 95% confidence interval [CI] 1.1-3.7) and autistic traits (3.5% vs. 0.9%; OR 2.7, CI 1.1-6.7) compared to children of parents without epilepsy. At 36 months, the exposed children had increased risk of abnormal score for gross motor skills (7.5% vs. 3.3%; OR 2.2, CI 1.1-4.2), sentence skills (11.2% vs. 4.8%; OR 2.1, CI 1.2-3.6), and autistic traits (6.0% vs. 1.5%; OR 3.4, CI 1.6-7.0). The drug-exposed children also had increased risk of congenital malformations (6.1% vs. 2.9%; OR 2.1, CI 1.4-3.4), but exclusion of congenital malformations did not affect the risk of adverse development. Children born to women with epilepsy who did not use antiepileptic drugs had no increased risks. Children of fathers with epilepsy generally scored within the normal range.

SIGNIFICANCE

Exposure to antiepileptic drugs during pregnancy is associated with adverse development at 18 and 36 months of age, measured as low scores within key developmental domains rated by mothers. Exposures to valproate, lamotrigine, carbamazepine, or multiple antiepileptic drugs were associated with adverse outcome within different developmental domains.

Mitochondrial diseases and epilepsy

The mitochondrial respiratory chain is the final common pathway for energy production. Defects affecting this pathway can give rise to disease that presents at any age and affects any tissue. However, irrespective of genetic defect, epilepsy is common and there is a significant risk of status epilepticus. This review summarizes our current understanding of the epilepsy that occurs in mitochondrial disease, focusing on three of the most common disorders: mitochondrial myopathy encephalopathy, lactic acidosis and stroke-like episodes (MELAS), myoclonus epilepsy and ragged-red fibers (MERRF), and polymerase gamma (POLG) related disease. In addition, we review the pathogenesis and possible treatment of these disorders.

Teratogene effekter av antiepileptika

 SAMMENDRAGCa. 1 av 200 gravide har epilepsi. Gravide med epilepsi har økt risiko for visse obstetriske komplikasjonerog for å føde barn med medfødte misdannelser. Risikoen for misdannelser synes koblet til bruk avantiepileptika under svangerskapet, og ikke til selve epilepsien. Alle typer misdannelser er økt, men leppeganespalteog nevralrørsdefekter utgjør særlig viktige misdannelser. Årsakene til misdannelsene er multifaktorielle.Bruk av antiepileptika i monoterapi kan sies å gi en individuell risiko for større misdannelser påca. 4-6%. Karbamazepin og natriumvalproat gir hhv. 0,5-1% og 2-3% risiko for nevralrørsdefekt. Samletrisiko for større og mindre anomalier inkludert dysmorfe ansiktstrekk synes ikke å overstige 10%. ENGLISH SUMMARYEngelsen BA. Teratogenic effects of antiepileptic drugs. Nor J Epidemiol 1997; 7 (1): 23-28.Approximately 1 in 200 pregnant women have epilepsy, and 1 in 250 births are to children of mothers whouse antiepleptic drugs (AED). Pregnant women with epilepsy have increased risk for certain obstetricalcomplications, and for giving birth to children with congenital malformations. The increased risk forcongenital malformations seems connected to the use of AED, not to the epileptic syndromes. The etiologyof congenital malformations are multifactorial. Use of AED in monotherapy is associated with anindividual risk of giving birth to a child with a major malformation of 4-6%. The specific risk of spinabifida is 0,5 to 1% for carbamazepine and 2-3% for sodium valproate.

Neuropsychological performance in patients with POLG1 mutations and the syndrome of mitochondrial spinocerebellar ataxia and epilepsy

Mutations in the catalytic subunit of polymerase gamma (POLG1) produce a wide variety of neurological disorders including a progressive ataxic syndrome with epilepsy: mitochondrial spinocerebellar ataxia and epilepsy (MSCAE). Our earlier studies of patients with this syndrome raised the possibility of more prominent right than left hemisphere dysfunction. To investigate this in more detail, eight patients (six women, two men; mean age: 22.3 years) were studied. All completed an intelligence test (Wechsler Adult Intelligence Scale; WAIS), and four were also given memory tests and a comprehensive neuropsychological test battery. Patients with MSCAE showed significant cognitive dysfunction. Mean Verbal IQ (84.3) was significantly better than Performance IQ (71.8) (t=5.23, P=0.001), but memory testing and neuropsychological testing failed to detect a consistent unilateral dysfunction. Further studies are needed to define the profile and development of cognitive symptoms in this disorder.

POLG1 mutations cause a syndromic epilepsy with occipital lobe predilection

The epileptic semiology of 19 patients (from 15 families) with mitochondrial disease due to mutations in the POLG1 gene is presented. The patients were either homozygous for the 1399G > A (p.A467T) or 2243G > C (p.W748S) mutations or compound heterozygotes for these two mutations. While the clinical features have been reviewed, detailed analysis of their epilepsy is presented for the first time. Irrespective of genotype, patients developed an epileptic syndrome with initial features of occipital lobe epilepsy. Occipital seizure phenomena included flickering coloured light, sometimes persisting for weeks, months or even years, ictal visual loss, horizontal/vertical nystagmus or oculoclonus, dysmorphopsia, micro-/macropsia and palinopsia. Most patients developed simple partial seizure phenomena with motor symptoms suggesting frontal lobe seizure initiation or spread. Simple and complex partial seizures, clonic- and/or myoclonic seizures with epilepsia partialis continua and frequent convulsive status epilepticus were observed in this syndrome that appears to be a symptomatic and secondary generalized or multifocal epilepsy with focal occipital predilection. The mean age of seizure presentation was 18.4 years (6-58 years). All patients developed status epilepticus and 11 patient deaths were, all related to prolonged convulsive status epilepticus, including two with liver failure apparently precipitated by treatment with sodium valproate.

Dichotic listening with forced attention in patients with temporal lobe epilepsy: Significance of left hemisphere cognitive dysfunction

Fifty right-handed patients with focal temporal lobe epilepsy were administered a dichotic listening test with consonant-vowel syllables under non-forced, forced right and forced left attention conditions, and a neuropsychological test battery. Dichotic listening performance was compared in subgroups with and without left hemisphere cognitive dysfunction, measured by the test battery, and in subgroups with left and right temporal epileptic focus. Left hemisphere cognitive dysfunction led to more correct responses to left ear stimuli in all three attention conditions, and fewer correct responses to right ear stimuli in the non-forced attention condition. This was probably caused by basic left hemisphere perceptual dysfunction. Dichotic listening was less affected by a left-sided epileptic focus than by left hemisphere cognitive dysfunction. General cognitive functioning influenced dichotic listening performance stronger in forced than in non-forced attention conditions. Larger cerebral networks were probably involved in the forced attention conditions due to the emphasis on conscious effort.

Frontoparietal activation during delayed visuospatial recall in patients with epilepsy due to hippocampal sclerosis

We hypothesized that brain activation during encoding and retrieval of visual material differed between epilepsy patients with hippocampal sclerosis (HS) and healthy controls. Eleven patients with epilepsy and HS and nine age- and education-matched control subjects were tested during functional MRI recording. A three-block design for visuospatial memory encoding and retrieval and an interference interval longer than 1 minute without memory tasks were used. All subjects revealed parietal, occipital, and prefrontal activation patterns during encoding. Interference revealed parietal more than occipital activation, whereas retrieval revealed asymmetrical frontal and parietal activation. Patients demonstrated a relative increase in occipitoparietal versus frontal cortical activation as compared with controls. Memory performance did not differ between patients and controls. The increased activation in occipitoparietal versus frontal areas in the patients suggests cortical reorganization of visuospatial recognition memory in epilepsy patients with HS. The study is limited by other factors that may contribute to the results, for example, antiepileptic drugs, effects of greater cognitive effort allocated in patients than controls, and possibly subclinical epileptic activity. However, normal visuospatial memory performance in our patients with HS suggests successful network plasticity.

The spectrum of clinical disease caused by the A467T and W748S POLG mutations: a study of 26 cases

We studied 26 patients belonging to 20 families with a disorder caused by mutations in the POLG gene. The patients were homozygous for 1399 G/A or 2243 G/C (giving the amino acid changes A467T and W748S, respectively) or compound heterozygotes for these two mutations. Irrespective of genotype, the patients exhibited a progressive neurological disorder usually starting in their teens and characterized by epilepsy, headache, ataxia, neuropathy, myoclonus and late onset ophthalmoplegia. However, major differences in survival were seen depending on genotype, with compound heterozygotes having a significantly shorter survival time than patients homozygous either for the A467T or W748S (P = 0.006). Epilepsy occurred in 22 of the 26 patients and in the majority of these there was an occipital EEG focus. Episodes of both generalized and focal motor status epilepticus were common and highly resistant to treatment, even with generalized anaesthesia. Status epilepticus was the recorded cause of death in 9 of 11 patients. Liver failure was the sole cause of death in two patients and evolved terminally in six others, all but one of whom were being treated with sodium valproate. Two patients underwent liver transplantation, but only one survived. Delayed psychomotor development and subsequent cognitive decline also occurs. This study demonstrates the clinical spectrum of a disorder that combines features of Alpers' syndrome and a later onset mitochondrial spinocerebellar ataxia with epilepsy and headache. Patients with this disorder are at high risk of death from status epilepticus and from liver failure, if exposed to sodium valproate. Each mutation appears capable of producing a disorder that is recessively inherited, although we also find evidence in one patient suggesting that heterozygotes may manifest. Compound heterozygotes have a significantly more severe phenotype raising the possibility of a dominant negative effect.

Autosomal recessive mitochondrial ataxic syndrome due to mitochondrial polymerase gamma mutations

OBJECTIVE

To investigate three families and one sporadic case with a recessively inherited ataxic syndrome.

METHODS

Clinical and genetic studies were performed in six individuals. Southern blotting and real time PCR were used to detect deletions of mtDNA and mutations in the POLG gene were identified using a combination of DHPLC and direct DNA sequencing.

RESULTS

The patients have a distinctive, progressive disorder that starts with episodic symptoms such as migraine-like headache or epilepsy. Ataxia, which is a combination of central and peripheral disease, develops later as does ophthalmoplegia. The commonest form of epilepsy was focal and involved the occipital lobes. Myoclonus was common and patients have a high risk of status epilepticus. MRI typically shows signal changes in the central cerebellum, olivary nuclei, occipital cortex, and thalami. COX negative muscle fibers were found in four of six; in one patient these were rare and in another absent. Multiple mtDNA deletions were identified in all patients, although in two these were not apparent on Southern blotting and real time PCR was required to demonstrate the defect. Two families were homozygous for a previously described POLG mutation, G1399A (A467T). One family and the sporadic case had the same two new mutations, a G to C at position 1491 (Q497H) and a G to C at 2243 (W748S).

CONCLUSIONS

Mutations in POLG cause a recessively inherited syndrome with episodic features and progressive ataxia. Characteristic changes on MRI are seen and although skeletal muscle may appear morphologically normal, multiple mtDNA deletions can be detected using real-time PCR.

Left hemisphere dysfunction affects dichotic listening in patients with temporal lobe epilepsy

This study evaluated the relative effect of left hemisphere dysfunction and side of seizure onset on dichotic listening performance in patients with temporal lobe epilepsy and left hemisphere speech dominance. Seventeen patients were divided into groups based on side of seizure onset and based on scores on a composite measure revealing left hemisphere dysfunction. The group with left hemisphere dysfunction had more correct responses from the left ear, and a left ear advantage, on dichotic listening. The group with normal left hemisphere function showed the expected right ear advantage. Side of seizure onset did not affect dichotic listening performance significantly.

[Status epilepticus]

The review defines status epilepticus and discusses treatment options for convulsive and nonconvulsive status epilepticus. The drug of choice in Norway is diazepam intravenously (0.25 mg/kg), followed by phosphenytoin or sodium valproate intravenously and barbiturate narcosis. Other treatment options are discussed. Underlying causes must be addressed for therapeutic intervention. Given early treatment, the prognosis is generally good.

The impact of affectivity dispositions, self-efficacy and locus of control on psychosocial adjustment in patients with epilepsy

The main hypothesis of this study was that negative and positive affectivity, self-efficacy and health-related locus of control are important for psychosocial adjustment in patients with epilepsy. These dimensions are rarely examined directly in relation to the psychosocial adjustment in these patients. Correlations between measures of these constructs and measures of psychosocial adjustment in epilepsy were investigated. One hundred and one patients answered the Washington psychosocial seizure inventory (WPSI), the positive and negative affect schedule (PANAS-X), the multidimensional health locus of control scales (MHLC), the generalized self-efficacy scale and a scale measuring self-efficacy in epilepsy. Reliability analyses, correlational analyses and multiple stepwise regression analyses were performed. Negative affectivity (NA), positive affectivity (PA) and generalized self-efficacy showed high correlations with the WPSI scales emotional adjustment, overall psychosocial adjustment and quality of life. The epilepsy self-efficacy measures showed high, but lower correlations with the same WPSI scales. The MHLC scales showed low correlations with the WPSI scales. Multiple regression analyses showed that PA, NA and measures of self-efficacy explained more than 50% of the variances on emotional adjustment, overall psychosocial functioning and quality of life. In conclusion, positive and negative affectivity and self-efficacy are important predictors of perceived emotional adjustment, psychosocial adjustment and quality of life in patients with epilepsy. NA is the best predictor, but PA and self-efficacy measures give unique predictions independent of NA.

Juvenile myoclonic epilepsy: clinical characteristics, treatment and prognosis in a Norwegian population of patients

Forty-three patients with juvenile myoclonic epilepsy (JME) is presented. The female to male ratio was 2.9:1. The patients answered a standardized questionnaire pertaining to social situation, medical history, onset of epilepsy, types and frequency of seizures, treatment, experienced control over seizures and consequences of having epilepsy. Myoclonic jerks, which are the hallmark of the condition, are often forgotten by the patients or not considered as epileptic seizures. This could be one reason why JME still seems underdiagnosed. JME may comprise absence, myoclonic and generalized tonic-clonic seizures (GTCS), proposed to occur in age-related sequence. We found that absence seizures may start after onset of other seizures. Our results confirm the need for medication since, during the last year, only 7% were seizure free without medication. Of patients on antiepileptic drugs (AEDs), 79.5% had no GTCS and 41% were seizure free during the last year, which confirms a relatively good response to appropriate treatment. Although most patients used AED daily and many still had one or more types of epileptic seizure, the epilepsy in general had very little impact on their lives.

Epileptic seizures in patients with multiple sclerosis. Is the prognosis of epilepsy underestimated?

The exact prevalence of epileptic seizures in patients with multiple sclerosis (MS) is still a matter of some controversy. In a population-based, unselected group of 423 patients with MS we identified 17 (4.02%) with epileptic seizures. The mean age at onset of MS was 25.2 years and at onset of epilepsy 32.6 years. A prevalence of 'active epilepsy', i.e. seizures within the last 5 years, was estimated to 3.2%. The prevalence of epilepsy in our MS population is much higher than should be expected when compared to lifetime prevalence of epilepsy in corresponding age groups. The occurrence of convulsive status epilepticus is also higher than expected, and suggests a rather serious prognosis. Thus, drug treatment should be considered after the first epileptic seizure.

Differential effect of carbamazepine and valproate monotherapy on plasma levels of oestrone sulphate and dehydroepiandrosterone sulphate in male epileptic patients

Steroid sulphates such as oestrone sulphate (OE1S) and dehydroepiandrosterone sulphate (DHEAS) have been suggested to be of biological importance in different disease states such as breast cancer and atherosclerosis. Previous studies have shown that drugs such as aminoglutethimide and rifampicin that induce P450-dependent mixed-function oxygenases selectively suppress plasma OE1S levels. The aim of this study was to evaluate the influence of treatment with carbamazepine, an antiepileptic drug known to stimulate mixed-function oxygenases, on plasma levels of OE1S and DHEAS. We measured plasma OE1S and DHEAS together with other plasma oestrogens and androgens in male epileptic patients before and during carbamazepine monotherapy. Patients treated with valproate monotherapy acted as a control group. Treatment with carbamazepine decreased plasma OE1S levels from a mean value of 810.8 to 411.6 pmol/l (mean suppression to 50.7% of pretreatment levels, P < 0.001). Similarly, the ratio of OE1S to OE1 fell to 59.9% of pretreatment levels (P < 0.001)). DHEAS decreased from a mean level of 4.9 mumol/l before treatment to 3.0 mumol/l during carbamazepine therapy (mean reduction to 62.7% of pretreatment levels (P < 0.001), while the ratio of DHEAS to DHEA fell to 63.0% of pretreatment values (P < 0.01). No significant change in plasma levels of the other oestrogens or androgens measured was observed. Treatment with valproate caused a slight decrease in FSH levels (P < 0.05), but no change in any of the other hormones measured was observed. Studies are warranted to evaluate the possible effects of long-term treatment with carbamazepine on the risk of developing endocrine-sensitive tumours and cardiovascular disease and also the possible effects of alterations in plasma DHEAS on epileptic activity.

Penicillin-induced convulsions have preferential effects on transmitter glutamate pools in rat neostriatum

Convulsant doses of penicillin and elevated ambient pressure of 41 bar enhance the excitability of neurons. Their effects have been studied in neostriatal tissue with methods allowing differentiation between transmitter and metabolic glutamate pools. Levels of glutamate (Glu), glutamine (Gln), aspartate (Asp); gamma-aminobutyric acid and taurine were measured in the intact and decorticated neostriatum and parieto-occipital cortex of rats with a unilateral frontal cortex ablation. Intravenous infusion of penicillin at 1 bar decreased the neostriatal Glu content in the intact but not in the decorticated hemisphere. Pressure of 41 bar significantly decreased the level of Asp in the decorticated side only. Infusion of penicillin at 41 bar reduced the levels of Glu by 20.1% and Gln by 21.0% in the intact neostriatum only, whereas it decreased the Asp level in both sides as compared to control. The cortical Glu content was decreased only after infusion of penicillin at 41 bar. The results suggest that intravenous penicillin has a more pronounced effect on transmitter than on metabolic Glu pools in rat brain.

Taurine treatment of dyskinesias: an attempt

Taurine is a sulfonic amino acid with inhibitory effects in the central nervous system. The clinical effect of taurine on dyskinesias was tested in an open trial with 14 patients. Taurine (3 g/day) was given orally in divided doses. Six patients showed an initial improvement which, however, did not persist to the end of the 6-week treatment period. No side effects were observed. It seems unlikely that taurine administration will prove effective in the symptomatic treatment of dyskinesias.

The acute effect of ammonium acetate on levels of amino acids in the intact and decorticated rat neostriatum

Unilateral frontal cortex ablations were performed in rats so that the glutamate terminals in the ipsilateral rostral neostriatum were removed. At 1 or 7 days later, intraperitoneal injections of ammonium acetate induced different changes in amino acid concentrations in the intact and deafferentated neostriatum. After 1 day, the level of glutamate decreased only in the intact side, whereas that of glutamine increased and that of aspartate decreased to the same extent on both sides following ammonia injection. After 7 days, the glutamate level decreased more in the intact than the decorticated side in both nonconvulsing and convulsing rats. The concentration of alanine increased most in the intact neostriatum, whereas glutamine levels increased and aspartate levels decreased to the same extent on both sides in nonconvulsing and convulsing rats. The results indicate that ammonia has a more pronounced effect on neuronal than glial glutamate pools.

Elevated concentrations of glutamate and aspartate in human ventricular cerebrospinal fluid (vCSF) during episodes of increased CSF pressure and clinical signs of impaired brain circulation

In the ventricular cerebrospinal fluid (vCSF) of 10 hydrocephalic patients the mean (+/- S.D.) concentrations of glutamate and asparate were 2.9 +/- 0.2 and 0.2 +/- 0.2 microM, respectively. Significantly higher concentrations of these amino acids were found in two patients (glutamate 37.8 and 22.4 microM, aspartate 2.2 and 0.6 microM) with symptoms of impaired brain tissue perfusion, i.e. relative ischemia due to severely increased intraventricular CSF pressure. Our results are consistent with recent experiments in rats showing increased extracellular concentrations of glutamate and aspartate during transient cerebral ischemia.