Children with epilepsy are affected by several factors, including clinical and social variables. Among these variables, cognitive decline and behavioral disturbances, perceptions of stigma, and fatigue can lead to reductions in quality of life (QOL). Epileptic activities, including seizure severity, frequent seizures, and status epilepticus (SE), have been identified as important predictors of QOL. In addition, the frequency of interictal epileptiform discharges (IEDs) on electroencephalogram (EEG) may also be an important predictor of QOL, because IEDs can lead to cognitive decline and behavioral disturbances. Moreover, frequent seizures and/or IEDs may play a role in emotional mediators, such as stigma and fatigue, in childhood epilepsy. Seizure severity and/or IEDs are, therefore, important QOL-related factors in childhood epilepsy.
1. Introduction
Quality of life (QOL) in children with epilepsy seems to be influenced by various factors, including clinical and social variables. Among these variables, cognitive decline and behavioral disturbances, perceptions of stigma, and fatigue can lead to reductions in QOL. These disturbances may be associated with epileptic activities. Thus, seizure control is critical because of the improvement in QOL
[1].
Among various epileptic activities, seizure severity, frequent seizures, and the presence of status epilepticus (SE) are regarded as the main QOL-related factors. Seizure clusters may be associated with higher seizure frequency, higher risk of treatment resistance, and lower likelihood of seizure remission, according to a systematic review
[2]. In children with seizure clusters, QOL could be lower than that in children with isolated seizures
[2]. Seizure clusters may also adversely affect the productivity of patients and their caregivers
[2]. In addition, frequent seizures and SE can lead to neuropsychological impairments
[3,4][3][4]. Accordingly, seizure severity may be associated with a reduction in QOL in children with epilepsy. On the other hand, electroencephalogram (EEG) findings, such as the frequency of interictal epileptiform discharges (IEDs), which are among the epileptic activities, may also be related to cognitive decline and behavioral disturbances
[5]. Like frequent seizures, IEDs on EEG could also mediate emotional states, including stigma and fatigue
[6]. These findings suggest that epileptic activities, including frequent seizures and the presence of SE and IEDs on EEG, may lead to reduced QOL in children with epilepsy.
On the other hand, stigma is regarded as an important QOL-related factor in epilepsy. The perception of stigma related to the epileptic condition may be very severe and is often under-recognized by clinicians
[7]. Stigma has a marked negative impact, not only for children but also their families. Reducing perceptions of stigma is, therefore, necessary for the clinical management of childhood epilepsy.
In addition, fatigue is also associated with reduced QOL in patients with epilepsy. Fatigue may correlate with psychosocial factors, including anxiety, depression, and sleep problems
[8]. In addition to these variables, epileptic activities may be associated with fatigue. A previous study showed that frequent seizures can lead to increased fatigue in epileptic patients
[9]. Thus, fatigue may also relate to epileptic activities.
Neuropsychological impairments in children with epilepsy, such as cognitive decline, behavioral disturbances, perception of stigma, and fatigue, that relate to frontal lobe dysfunction can be caused by several factors. Frontal lobe lesions may lead to these disturbances in consonance with lesion location. However, children with no lesions can also present with these disturbances. A previous study showed a negative correlation between the frequency of IEDs on EEG and cognitive function in self-limited epilepsy with centrotemporal spike (SeLECTS)
[10]. These disturbances may thus relate to epileptic activities and topography. The frontal lobes mature over a long period and so are easily damaged by various factors. Damage to the frontal regions during childhood interferes with maturational and organizational processes, which can lead to neuropsychological impairments
[11]. Results from previous investigations have suggested that severe seizures, as reflected by certain statuses, such as frequent seizures and SE, can impair the developing brain
[11,12,13][11][12][13]. In combination with these studies, seizure severity and IEDs on EEG may lead to cognitive, behavioral, and psychological disturbances. Epileptic activities, such as seizure severity and/or IEDs, are important QOL-related factors in childhood epilepsy.
2. Seizure Severity in Childhood Epilepsy
2.1. Seizure Severity and Cognitive/Behavioral Disturbances
Neuropsychological impairments, such as cognitive decline and behavioral disturbances, reduce QOL in childhood epilepsy and may be induced by frontal lobe dysfunction. In addition, QOL reduction in children can also reduce QOL in the family. Thus, frontal lobe dysfunction can result in reduced QOL for both the child and their family.
The frontal lobes are the largest cortical regions of the brain, comprising approximately 40% of the cerebral cortex. Among these regions, the prefrontal regions involve wide networks
[14]. Because of these connections, the prefrontal cortex can receive abundant information from all parts of the cerebrum and can affect information processing in those parts. Prefrontal lobe neurons and glial cells are readily influenced by various factors, so prefrontal lobe functions are regarded as being vulnerable for a long period
[15]. Accordingly, severe seizures, such as frequent or prolonged seizures, result in negative effects on prefrontal lobe functions more easily than on other cortical regions
[14,15][14][15]. Considering these findings, epilepsy associated with prefrontal regions in children may be associated with several neuropsychological impairments in comparison with healthy subjects
[3].
In other cerebral regions, seizures can result in memory and learning disturbances, which relate to temporal lobe dysfunctions
[16]. Temporal lobe seizures can also lead to behavioral disturbances
[17]. However, direct relationships between seizures and temporal or other cerebral lobe functioning have not been fully revealed. Further research is needed to discuss these aspects.
2.1.1. Prefrontal Lobe Growth in Frontal Lobe Epilepsy
Understanding how frontal lobe epilepsy (FLE) impacts the life of patients is important. In a serial three-dimensional (3D) magnetic resonance imaging (MRI) volumetric study, the growth of the frontal and prefrontal lobes in children with drug-responsive FLE without neuropsychological impairments was similar to that in healthy subjects
[3]. In contrast, frontal and prefrontal lobe growth disturbances were present during the active epileptic phase in refractory FLE patients with cognitive decline and behavioral disturbances. However, a difference associated with the active seizure period was present. A short active seizure period was associated with prompt growth recovery. In children with a longer active seizure period, the growth disturbance was more severe, and growth recovery took longer
[3] (
Table 1). Frequent seizures in children with FLE may thus induce prefrontal lobe growth disturbances, which can lead to neuropsychological impairments.
Table 1.
Associations between seizure severity and prefrontal lobe growth disturbances.