Prediction of Drug-Resistant Epilepsy in Children With Cerebral Palsy

Clinical features associated with epilepsy occurrence, resolution, and drug resistance in children with cerebral palsy: A population-based study

AIM

To investigate clinicoradiological features associated with epilepsy, its resolution, and drug resistance in children with cerebral palsy (CP).

METHOD

Data were gathered from the New South Wales/Australian Capital Territory CP Register, encompassing children with CP born between 2003 and 2015 (n = 1916). Clinical features and the severity of impairments were compared among three groups: children with current epilepsy (n = 604), those with resolved epilepsy by age 5 years (n = 109), and those without epilepsy (n = 1203). Additionally, a subset of the registry cohort attending Children's Hospital Westmead (n = 256) was analysed to compare epilepsy and treatment characteristics between drug-responsive (n = 83) and drug-resistant groups (n = 147) using logistic regression and hierarchical cluster analysis.

RESULTS

Manual Ability Classification System levels IV and V, intellectual impairment, and vision impairment were found to be associated with epilepsy in children with CP on multivariable analysis (p < 0.01). Moderate to severe intellectual impairment and bilateral spastic CP were independent positive and negative predictors of epilepsy persistence at the age of 5 years respectively (p < 0.05). Microcephaly and multiple seizure types were predictors of drug-resistant epilepsy (area under the receiver operating characteristic curve of 0.83; 95% confidence interval 0.77-0.9). Children with a known genetic cause (14%) and CP epilepsy surgery group (4.3%) formed specific clinical subgroups in CP epilepsy.

INTERPRETATION

Our study highlights important clinical associations of epilepsy, its resolution, and treatment response in children with CP, providing valuable knowledge to aid in counselling families and identifying distinct prognostic groups for effective medical surveillance and optimal treatment.

WHAT THIS PAPER ADDS

Severe motor and non-motor impairments in cerebral palsy (CP) increase epilepsy risk. Epilepsy more likely resolves in bilateral spastic and milder CP impairments. Epilepsy in CP often manifests at an early age with multiple seizure types and high drug resistance. Children with a known genetic cause and CP epilepsy surgery group represent distinct clinical subgroups.

Association of epilepsy with neuroimaging patterns in children with cerebral palsy

OBJECTIVES

In this study, we examined whether epilepsy and drug-resistant epilepsy are associated with neuroimaging findings in children with cerebral palsy (CP).

METHODS

Magnetic resonance imaging classification system (MRICS) proposed by Surveillance of Cerebral Palsy in Europe (SCPE) was used for classification of different MRI patterns in patients with cerebral palsy. We reviewed the brain MRI scans and medical records of children with CP who were followed-up in our clinic between 2019 and 2023. Patients were divided into three categories: CP without epilepsy, CP with controlled epilepsy and CP with DRE. MRI patterns were grouped as maldevelopments, predominant white matter injury, predominant gray matter injury, miscellaneous (delayed myelination, cerebral atrophy, cerebellar atrophy, brainstem lesions and calcifications, lesions that were not classified under any other group) and normal according to MRICS of the SCPE.

RESULTS

There were 325 CP patients. The most common MRI patterns were predominant white matter injury (47.6%) and gray matter injury (23.8%). There was a 1.5-fold reduction in the risk of epilepsy in patients with predominant white matter injury (OR = 1.54, 95% CI 1.23-1.94). In contrast, children in the miscellaneous group had significantly higher risks of epilepsy (p < 0.001), and we were able to determine that miscellaneous findings increased the risk by 1.8 times (OR = 1.77, 95% CI 1.47-2.12).

CONCLUSION

In conclusion, more than half of the children with CP had epilepsy, 40.7% of whom had DRE. On MRI, miscellaneous findings may indicate a poor prognosis for epilepsy, while predominant white matter injury may indicate a good outcome. Children with CP, especially those with miscellaneous findings on MRI, should be closely monitored for epilepsy development.

Risk factors and outcome of epilepsy in adults with cerebral palsy or intellectual disability

INTRODUCTION

Epilepsy is found in 10-60% of individuals with cerebral palsy (CP) and 5.5-35% with intellectual disability (ID). However, little is known about the long-term evolution of epilepsy among adults. The aim of the study is to describe the factors associated with epilepsy and its outcome in a population of adults with CP or ID.

METHODS

This retrospective study reviewed the medical records of 306 individuals with CP/ID. All individuals underwent neurological, psychiatric, and neuropsychological follow-ups.

RESULTS

In the cohort, 72.5% of the individuals had a CP diagnosis, with a mean age of 36.4 years (IQR 24.0-46.0). Epilepsy was present in 55.6% of the individuals and was associated with CP (p < 0.01), spastic subtype (p < 0.01), a higher degree of ID (p < 0.01), hemorrhagic and congenital malformation etiologies (p 0.011), abnormal neuroimaging (p < 0.01), and worse scores on motor and communication scales (p < 0.01). Drug-resistant epilepsy (DRE) (22.4%) was associated with higher scores on motor scales (p < 0.01). Additionally, 42.3% of the individuals who attempted antiseizure medication (ASM) withdrawal experienced recurrence, which was associated with epileptic activity on the electroencephalogram (EEG) (p 0.004).

CONCLUSIONS

Epilepsy is a common comorbidity in adults with CP or ID and is associated with greater brain damage and a more severe phenotype. Seizure recurrence after ASM withdrawal occurred in half of the individuals and was associated with epileptic activity on the EEG.

Epilepsy syndromes in cerebral palsy: varied, evolving and mostly self-limited

Seizures occur in approximately one-third of children with cerebral palsy. This study aimed to determine epilepsy syndromes in children with seizures and cerebral palsy due to vascular injury, anticipating that this would inform treatment and prognosis. We studied a population-based cohort of children with cerebral palsy due to prenatal or perinatal vascular injuries, born 1999-2006. Each child's MRI was reviewed to characterize patterns of grey and white matter injury. Children with syndromic or likely genetic causes of cerebral palsy were excluded, given their inherent association with epilepsy and our aim to study a homogeneous cohort of classical cerebral palsy. Chart review, parent interview and EEGs were used to determine epilepsy syndromes and seizure outcomes. Of 256 children, 93 (36%) had one or more febrile or afebrile seizures beyond the neonatal period and 87 (34%) had epilepsy. Children with seizures were more likely to have had neonatal seizures, have spastic quadriplegic cerebral palsy and function within Gross Motor Function Classification System level IV or V. Fifty-six (60%) children with seizures had electroclinical features of a self-limited focal epilepsy of childhood; we diagnosed these children with a self-limited focal epilepsy-variant given the current International League Against Epilepsy classification precludes a diagnosis of self-limited focal epilepsy in children with a brain lesion. Other epilepsy syndromes were focal epilepsy-not otherwise specified in 28, infantile spasms syndrome in 11, Lennox-Gastaut syndrome in three, genetic generalized epilepsies in two and febrile seizures in nine. No epilepsy syndrome could be assigned in seven children with no EEG. Twenty-one changed syndrome classification during childhood. Self-limited focal epilepsy-variant usually manifested with a mix of autonomic and brachio-facial motor features, and occipital and/or centro-temporal spikes on EEG. Of those with self-limited focal epilepsy-variant, 42/56 (75%) had not had a seizure for >2 years. Favourable seizure outcomes were also seen in some children with infantile spasms syndrome and focal epilepsy-not otherwise specified. Of the 93 children with seizures, at last follow-up (mean age 15 years), 61/91 (67%) had not had a seizure in >2 years. Children with cerebral palsy and seizures can be assigned specific epilepsy syndrome diagnoses typically reserved for normally developing children, those syndromes commonly being age-dependent and self-limited. Compared to typically developing children with epilepsy, self-limited focal epilepsy-variant occurs much more commonly in children with cerebral palsy and epilepsy. These findings have important implications for treatment and prognosis of epilepsy in cerebral palsy, and research into pathogenesis of self-limited focal epilepsy.

Characteristics and Challenges of Epilepsy in Children with Cerebral Palsy-A Population-Based Study

The aim of this population-based study was to describe the prevalence and characteristics of epilepsy in children with cerebral palsy (CP), focusing on antiseizure medication (ASM) and seizure outcome. Findings were related to CP type, gross motor function and associated impairments. Data on all 140 children with CP born in 2003-2006 were taken from the CP register of Western Sweden. Medical records were reviewed at ages 9-12 and 13-16 years. In total 43% had a diagnosis of epilepsy. Epilepsy was more common in children with dyskinetic CP, who more often had a history of infantile spasms, continuous spike-and-wave during sleep and status epilepticus. Neonatal seizures, severe intellectual disability, severe motor disability and autism were associated with a higher risk of epilepsy. Many children were on polytherapy, and valproate was frequently used, even in girls. At age 13-16 years, 45% of the children with epilepsy were seizure free for at least one year. Onset after 2 years of age, female sex and white matter injury were associated with good seizure outcome. Despite the risk of relapse, reduction or discontinuation of ASM could be an option in selected cases. It is important to optimize ASM and to consider the possibility of epilepsy surgery.

Potential clinical and biochemical markers for the prediction of drug-resistant epilepsy: A literature review

Drug resistance is a major challenge in the treatment of epilepsy. Drug-resistant epilepsy (DRE) accounts for 30% of all cases of epilepsy and is a matter of great concern because of its uncontrollability and the high burden, mortality rate, and degree of damage. At present, considerable research has focused on the development of predictors to aid in the early identification of DRE in an effort to promote prompt initiation of individualized treatment. While multiple predictors and risk factors have been identified, there are currently no standard predictors that can be used to guide the clinical management of DRE. In this review, we discuss several potential predictors of DRE and related factors that may become predictors in the future and perform evidence rating analysis to identify reliable potential predictors.

Interictal brain activity changes in temporal lobe epilepsy: A quantitative electroencephalogram analysis

OBJECTIVES

To evaluate the usefulness of quantitative electroencephalography (qEEG) in the analysis of baseline activity in patients with temporal lobe epilepsy (TLE) and identify measures potentially associated with disease duration and drug resistance.

MATERIALS AND METHODS

Cross-sectional study of adult patients with TLE and controls who underwent video-EEG monitoring. Representative artifact-free resting wakefulness baseline EEG segments were selected for quantitative analysis. The fast Fourier transform (FFT) approach was used for the power spectral analysis, with computation of FFT power ratios and alpha-delta and alpha-theta ratios for both hemispheres. The resulting measures were compared between TLE patients and controls and their values as predictors of epilepsy duration and drug resistance analyzed.

RESULTS

Thirty-nine TLE patients and 23 controls were included. The TLE patients had a lower alpha-delta ratio in the posterior quadrant ipsilateral to the epileptic focus and a lower alpha-theta ratio in the ipsilateral anterior/posterior quadrants and temporal region. A younger age at onset and longer epilepsy duration correlated with a higher theta power ratio in the contralateral anterior and posterior quadrants and temporal region. No qEEG measures predicted drug resistance.

CONCLUSIONS

Quantitative electroencephalography background activity may contribute to the diagnosis of TLE and provide useful information on disease duration. A lower alpha-delta and alpha-theta ratio may be reliable baseline qEEG measures for identifying patients with TLE. A higher contralateral theta power ratio may be indicative of longer epilepsy duration.

A Self-Limited Childhood Epilepsy as Co-Incidental in Cerebral Palsy

Background

Cerebral palsy is the most frequent motor disability in childhood and is associated with a higher incidence of seizure disorders. In many instances, it is recognized that motor difficulties, as well as seizures, are from the same underlying brain lesion. However, self-limited childhood epilepsies, being a common group of epilepsy syndromes, would be expected to occur in patients with cerebral palsy merely on chance association and be unrelated to the structural brain imaging abnormality causing the motor impairment. Differential diagnosis in this case is important determining the long-term prognosis and need for anticonvulsant treatment.

Case Presentation

Here, we report two patients with cerebral palsy combined with epilepsy, whose age at onset, seizure semiology and electroclinical features were similar to children with self-limited childhood-specific seizure disorders (childhood epilepsy with centrotemporal spikes and Panayiotopoulos syndrome).

Conclusion

These cases highlight the importance of comprehensive differential diagnosis of seizures in cerebral palsy. Co-existence of age-dependent focal epilepsies with an underlying brain pathology as white matter injury, not affecting the cerebral cortex, might take place in the case of children with impaired motor skills. With health systems increasingly utilizing clinical pathways, it is important to consider the possibility of a self-limited childhood epilepsy and avoid aggressive and unnecessary medication treatment in children with cerebral palsy.

Models for predicting treatment efficacy of antiepileptic drugs and prognosis of treatment withdrawal in epilepsy patients

Although antiepileptic drugs (AEDs) are the most effective treatment for epilepsy, 30–40% of patients with epilepsy would develop drug-refractory epilepsy. An accurate, preliminary prediction of the efficacy of AEDs has great clinical significance for patient treatment and prognosis. Some studies have developed statistical models and machine-learning algorithms (MLAs) to predict the efficacy of AEDs treatment and the progression of disease after treatment withdrawal, in order to provide assistance for making clinical decisions in the aim of precise, personalized treatment. The field of prediction models with statistical models and MLAs is attracting growing interest and is developing rapidly. What’s more, more and more studies focus on the external validation of the existing model. In this review, we will give a brief overview of recent developments in this discipline.