Outcome at age 7 of epilepsy presenting in the first 2 years of life. A population-based study

Objective

Existing data suggest that epilepsy presenting in the first few years of life carries a worse prognosis than later onset. However, studies are few and methods differ, making interpretations of data uncertain. This study analyzes outcome at age 7 and potential prognostic factors in a well‐characterized population‐based cohort with epilepsy onset during the first 2 years of life.

Methods

An incidence cohort of 116 prospectively identified cases of epilepsy with seizure onset before age 2 years was described in Stödberg et al. (2020). Cases were originally retrieved from the Stockholm Incidence Registry of Epilepsy (SIRE), which registered all cases with a first unprovoked epileptic seizure from September 1, 2001, in Northern Stockholm. Data on treatment and outcome at age 7 years were collected from electronic medical records and through interviews with parents. Outcome and potential prognostic factors were analyzed with descriptive statistics and multivariable log binomial regression analysis.

Results

Eleven children (9.5%) died before age 7. Polytherapy was common. Epilepsy surgery was performed in two children. At age 7 years, 61 of 116 children (53%) had been seizure‐free for the last 2 years or longer. Intellectual disability was diagnosed in 57 of 116 children (49%), autism spectrum disorder in 13 (11%), and cerebral palsy in 28 (24%). West syndrome had a similar seizure remission rate but a worse cognitive outcome. There was no difference in outcome between first and second year onset. Six predictors, including etiology, remained associated with two or more outcome variables after regression analysis.

Significance

About half of children with infantile‐onset epilepsy will become seizure‐free and half of them will have intellectual disability. Etiology was confirmed as a major independent predictor of outcome. Our study contributes to a more firm knowledge base when counseling parents of infants diagnosed with epilepsy.

Epilepsy syndromes, etiologies, and the use of next-generation sequencing in epilepsy presenting in the first 2 years of life: A population-based study

OBJECTIVE

Population-based data on epilepsy syndromes and etiologies in early onset epilepsy are scarce. The use of next-generation sequencing (NGS) has hitherto not been reported in this context. The aim of this study is to describe children with epilepsy onset before 2 years of age, and to explore to what degree whole exome and whole genome sequencing (WES/WGS) can help reveal a molecular genetic diagnosis.

METHODS

Children presenting with a first unprovoked epileptic seizure before age 2 years and registered in the Stockholm Incidence Registry of Epilepsy (SIRE) between September 1, 2001 and December 31, 2006, were retrieved and their medical records up to age 7 years reviewed. Children who met the epilepsy criteria were included in the study cohort. WES/WGS was offered in cases of suspected genetic etiology regardless of whether a structural or metabolic diagnosis had been established.

RESULTS

One hundred sixteen children were included, of which 88 had seizure onset during the first year of life and 28 during the second, corresponding to incidences of 139 and 42/100 000 person-years, respectively. An epilepsy syndrome could be diagnosed in 54% of cases, corresponding to a birth prevalence of 1/1100. Structural etiology was revealed in 34% of cases, a genetic cause in 20%, and altogether etiology was known in 65% of children. The highest diagnostic yield was seen in magnetic resonance imaging (MRI) with 65% revealing an etiology. WES/WGS was performed in 26/116 cases (22%), with a diagnostic yield of 58%.

SIGNIFICANCE

Epilepsy syndromes can be diagnosed and etiologies revealed in a majority of early onset cases. NGS can identify a molecular diagnosis in a substantial number of children, and should be included in the work-up, especially in cases of epileptic encephalopathy, cerebral malformation, or metabolic disease without molecular diagnosis. A genetic diagnosis is essential to genetic counselling, prenatal diagnostics, and precision therapy.

Copy number variations in children with brain malformations and refractory epilepsy

Brain malformations are a major cause of therapy-refractory epilepsy as well as neurological and developmental disabilities in children. This study examined the frequency and the nature of copy number variations among children with structural brain malformations and refractory epilepsy. The medical records of all children born between 1990 and 2009 in the epilepsy registry at the Astrid Lindgren's Children's Hospital were reviewed and 86 patients with refractory epilepsy and various brain malformations were identified. Array-CGH analysis was performed in 76 of the patients. Pathogenic copy number variations were detected in seven children (9.2%). In addition, rearrangements of unclear significance, but possibly pathogenic, were detected in 11 (14.5%) individuals. In 37 (48.7%) patients likely benign, but previously unreported, copy number variants were detected. Thus, a large proportion of our patients had at least one rare copy number variant. Our results suggest that array-CGH should be considered as a first line genetic test for children with cerebral malformations and refractory epilepsy unless there is a strong evidence for a specific monogenic syndrome.

The incidence of unprovoked seizures and occurrence of neurodevelopmental comorbidities in children at the time of their first epileptic seizure and during the subsequent six months

PURPOSE

To evaluate the incidence of unprovoked seizures in children and the prevalence of related neurodevelopmental comorbidities at the time of the presumed first seizure and six months thereafter.

METHODS

The medical records of all children (0-18 years of age) seeking medical attention as the result of a first unprovoked seizure between September 1, 2001 and December 31, 2006, and registered in the population-based Stockholm Incidence Registry of Epilepsy (SIRE) were reviewed. Neurodevelopmental comorbidities were evaluated on the basis of the medical records from this first visit and from other healthcare during the following six months.

RESULTS

The incidence of unprovoked seizures was between 30 and 204/100,000 person years (n=766) in the different age groups. It was highest among the youngest children and lowest among the 18-year-olds with small gender differences. The most common neurodevelopment comorbidities were developmental delay (22%, CI: 19-25%), speech/language and learning difficulties (23%, CI: 20-26%) and intellectual disability (16%, CI: 13-18%). The types of neurodevelopmental comorbidity varied by age at the time of seizure onset, with cerebral palsy being more common among the 0-5-year-olds, attention deficits among the 6-16-year-olds, and autism and psychiatric diagnosis among the older children. An associated neurodevelopmental comorbidity was more common among those experiencing recurrent than single seizures during follow-up six months from the index seizure (42% versus 66%). In 68% (CI: 64-71%) of the children there was no known or suspected neurodevelopmental comorbidity.

CONCLUSION

The incidence of unprovoked, non-febrile seizures among 0-18-year-olds included in the SIRE was 67/100,000 person-years. Neurodevelopmental comorbidities were common already at the time of onset of the seizure disorder, indicating that neither seizure treatment nor seizures were the underlying cause of other neurodevelopmental symptoms in these patients during the period studied.

Effectiveness of the ketogenic diet used to treat resistant childhood epilepsy in Scandinavia

BACKGROUND

This Scandinavian collaborative retrospective study of children treated with ketogenic diet (KD) highlights indications and effectiveness over two years follow-up.

METHODS

Five centres specialised in KD collected data retrospectively on 315 patients started on KD from 1999 to 2009. Twenty-five patients who stopped the diet within four weeks because of compliance-problems and minor side-effects were excluded. Seizure-type(s), seizure-frequency, anti-epileptic drugs and other treatments, mental retardation, autism-spectrum disorder and motor-dysfunction were identified and treatment-response was evaluated.

RESULTS

An intention-to-treat analysis was used. Responders (>50% seizure-frequency reduction) at 6, 12 and 24 months were 50%, 46% and 28% respectively, seizure-free were 16%, 13% and 10%. Still on the diet were 80%, 64% and 41% after 6, 12 and 24 months. No child had an increased seizure-frequency. The best seizure outcome was seen in the group with not-daily seizures at baseline (n = 22), where 45%, 41% and 32% became seizure-free at 6, 12 and 24 months A significant improvement in seizure-frequency was seen in atonic seizures at three months and secondary generalised seizures at three and six months. Side-effects were noted in 29 subjects; most could be treated and only two stopped due to hyperlipidaemia and two due to kidney-stones. In 167 patients treated with potassium-citrate, one developed kidney-stones, compared with six of 123 without potassium-citrate treatment (relative risk = 8.1).

CONCLUSIONS

As the first study of implementing KD in children in the Scandinavian countries, our survey of 290 children showed that KD is effective and well tolerated, even in such severe patients with therapy-resistant epilepsy, more than daily seizures and intellectual disability in the majority of patients. Long-term efficacy of KD was comparable or even better than reported in newer AEDs. Addition of potassium citrate reduced risk of kidney-stones. Our data indicate that the response might be predicted by seizure-frequency before initiation of the diet but not by age, seizure-type or aetiology.

Presurgical language lateralization assessment by fMRI and dichotic listening of pediatric patients with intractable epilepsy

Objective

The aim of this study was to evaluate the clinical use of a method to assess hemispheric language dominance in pediatric candidates for epilepsy surgery. The method is designed for patients but has previously been evaluated with healthy children.

Methods

Nineteen patients, 8–18 years old, with intractable epilepsy and candidates for epilepsy surgery were assessed. The assessment consisted of two functional MRI protocols (fMRI) intended to target frontal and posterior language networks respectively, and a behavioral dichotic listening task (DL). Regional left/right indices for each fMRI task from the frontal, temporal and parietal lobe were calculated, and left/right indices of the DL task were calculated from responses of consonants and vowels, separately. A quantitative analysis of each patient's data set was done in two steps based on clearly specified criteria. First, fMRI data and DL data were analyzed separately to determine whether the result from each of these assessments were conclusive or not. Thereafter, the results from the individual assessments were combined to reach a final conclusion regarding hemispheric language dominance.

Results

For 14 of the 19 subjects (74%) a conclusion was reached about their hemispheric language dominance. Nine subjects had a left-sided and five subjects had a right-sided hemispheric dominance. In three cases (16%) DL provided critical data to reach a conclusive result.

Conclusions

The success rate of conclusive language lateralization assessments in this study is comparable to reported rates on similar challenged pediatric populations. The results are promising but data from more patients than in the present study will be required to conclude on the clinical applicability of the method.

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Language lateralization was assessed in 19 pediatric candidates for epilepsy surgery.

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The assessment involved fMRI and an independent behavioral measure; dichotic listening.

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A two step analysis was employed combining fMRI and dichotic listening data.

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For 74% of the subjects a conclusion was reached about hemispheric language dominance.

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The rate of conclusive assessments in this study is comparable to reported rates on similar challenged pediatric populations.

Growth charts and long-term sequelae in extreme preterm infants--from full-term age to 10 years

AIM

To describe growth pattern from full-term age to 10 years in infants born before 26 weeks of gestation.

METHOD

This retrospective longitudinal cohort contained 123 children from Karolinska Hospital, Stockholm, during 1990-2002. Length/height (Ht), weight (Wt) and head circumference (HC) were recorded monthly during the first year, every 3 months until 2 years and yearly thereafter, but HC at 15 months and at median age of 8.1/9.7 years (range 2-14) in boys/girls.

RESULTS

For boys/girls at birth, the mean Z-score for Ht was -0.2/-0.2, for Wt 0.0/-0.2 and for HC 0.0/-0.3. At term, the mean Z-score for Ht was -3.8/-3.1, for Wt -3.0/-2.5 and for HC -1.7/-1.2. At 1 year, the mean Z-score for Ht was-1.3/-1.3, for Wt -1.9/-1.7 and for HC -1.2/-1.0. At 2 years, the mean Z-score for Ht was -1.3/-1.1, for Wt -1.6/-1.2 and at 10 years for Ht -0.7/-0.4; that was on average -0.3 below mid-parental height; for Wt -0.2/-0.2. Long-term sequelae were found in 48% of the boys and 34% of the girls.

CONCLUSION

By 10 years of age, the attained mean Ht was in accordance with their genetic potential and almost half of these children had significant long-term sequelae.

Medical conditions affect the outcome of early intervention in preschool children with autism spectrum disorders

The aim was to explore the frequency of genetic and other medical conditions, including epilepsy, in a population-based group of 208 preschool children with early diagnosis of Autism spectrum disorders (ASD) and to relate outcome at a 2-year follow-up to the co-existing medical findings. They had all received early intervention. The Vineland Adaptive Behaviour Scales (VABS-II) composite score served as the primary outcome measure. In the total group, 38/208 children (18 %) had a significant medical or genetic condition. Epilepsy was present in 6.3 % at the first assessment and in 8.6 % at follow-up and was associated with more severe intellectual impairment. A history of regression was reported in 22 %. Children with any medical/genetic condition, including epilepsy, as well as children with a history of regression had significantly lower VABS-II scores at the 2-year follow-up. Children with a medical/genetic condition, including epilepsy, had been diagnosed with ASD at an earlier age than those without such conditions, and early age at diagnosis also correlated negatively with adaptive functioning outcome. The results underscore the importance of considering medical/genetic aspects in all young children with ASD and the requirement to individualize and tailor interventions according to their specific needs.