The relationship between epilepsy, sleep disorders, and attention deficit hyperactivity disorder (ADHD) in children: A review of the literature

Sleep disorders and ADHD symptoms in children and adolescents with typical absence seizures: An observational study

OBJECTIVE

To assess the occurrence of sleep disorders (SD) and attention deficit hyperactivity disorder (ADHD) symptoms in children with typical absence seizures (TAS) compared to control children and to evaluate the impact of epilepsy-related factors on sleep and attention in children with TAS.

METHODS

The Sleep Disturbance Scale for Children (SDSC) and the ADHD rating scale were filled in by parents of a cohort composed by 82 children aged from 5 to 15.6 years, 49% of boys (41 with TAS with a syndromic diagnosis of childhood absence epilepsy and 41 controls). For children with TAS, the Pediatric Epilepsy Side Effects Questionnaire was completed. Statistical analyses were conducted in order to compare sleep and attention scores between groups. In children with TAS, a correlation was computed between these scores. Logistics regression models were conducted to identify predictors of excessive diurnal sleepiness and inattention in children with TAS.

RESULTS

Compared to controls, children with TAS had higher total scores for subjective sleep (mean 42.9 vs 38.3, p = 0.05) and attention disorders (mean 16.8 vs 11.6, p = 0.01), especially for excessive diurnal sleepiness (mean 3.9 vs 3.2, p = 0.02) and inattention (mean 9.3 vs 5.6, p = 0.003) components. In children with TAS, sleep problems were significantly under-reported by parents. Sleep disorders symptoms as breathing-related sleep disturbance, excessive diurnal sleepiness or naps at or after 7 years of age were reported. Subjective sleep and attention disorders were significantly correlated (r = 0.43, p = 0.01). Subjective excessive diurnal sleepiness may be the result of a polytherapy (p = 0.05) or a side effect of anti-seizure medication (ASM) (p = 0.03) but children without medication side effects also reported subjective SD. In children with TAS, the risk of inattention symptoms was increased in boys (p = 0.02), with a high BMI (p = 0.05), or with ASM side effects (p = 0.03).

CONCLUSIONS

This study demonstrates that children with TAS are at risk of sleep and attention disorder symptoms. If attention disorders in a context of epilepsy are now widely assessed and identified, sleep disorders are still under-estimated. An accurate identification and management of sleep disorders could improve academic performances, quality of life, and seizure management in children with TAS.

Sleep Power Topography in Children with Attention Deficit Hyperactivity Disorder (ADHD)

OBJECTIVE

Recent years saw an increasing interest towards sleep microstructure abnormalities in attention-deficit/hyperactivity disorder (ADHD). However, the existing literature on sleep electroencephalographic (EEG) power in ADHD is still controversial, often based on single electrode recordings, and mainly focused on slow wave activity (SWA) during NREM sleep. This study aimed to systematically investigate sleep power topography in all traditional frequency bands, in all sleep stages and across sleep cycles using high-density EEG (HD-EEG).

METHOD

Thirty drug-naïve children with ADHD (10.5 ± 2.1 years, 21 male) and 23 typically developing (TD) control participants (mean age: 10.2 ± 1.6 years, 13 male) were included in the current analysis. Signal power topography was computed in classical frequency bands during sleep, contrasted between groups and sleep cycles, and correlated with measures of ADHD severity, cognitive functioning and estimated total sleep time.

RESULTS

Compared to TD subjects, patients with ADHD consistently displayed a widespread increase in low-frequency activity (between 3 and 10 Hz) during NREM sleep, but not during REM sleep and wake before sleep onset. Such a difference involved a wide centro-posterior cluster of channels in the upper SWA range, in Theta, and low-Alpha. Between-group difference was maximal in sleep stage N3 in the first sleep cycle, and positively correlated with average total sleep time.

CONCLUSIONS

These results support the concept that children with ADHD, compared to TD peers, have a higher sleep pressure and altered sleep homeostasis, which possibly interfere with (and delay) cortical maturation.

Sleep microstructure in attention deficit hyperactivity disorder according to the underlying sleep phenotypes

The analysis of sleep microstructure in attention deficit hyperactivity disorder (ADHD) revealed an under-representation of the EEG slow component during NREM sleep. Previous studies either excluded or did not characterize objectively sleep disorders, which notoriously affect sleep architecture. The present study aimed to investigate the cyclic alternating pattern in a real clinical sample of children with ADHD, in whom sleep disorders could be considered. Twenty-seven consecutively enrolled drug-naïve children (mean age, 10.53 years; nine females) and 23 controls (mean age, 10.22 years; 11 females) underwent a full sleep investigation, including attended video-polysomnography. Visual cyclic alternating pattern analysis was performed in a blinded way. Children with ADHD had one or more sleep disorders (a narcolepsy-like phenotype was found in two cases, sleep onset insomnia in three cases, arousal disorder in one case, movement disorder phenotype in six cases and obstructive sleep apnea in 11 cases, and six children had sleep-related epileptiform discharges). Children with ADHD and normal controls showed a similar microstructure with a cyclic alternating pattern rate of about 50%. Children with obstructive sleep apnea had a significantly higher cyclic alternating pattern rate during stage N3. Despite not reaching statistical differences, a lower cyclic alternating pattern rate and A1 index were found in children without epileptic abnormalities/obstructive sleep apnea. Our analysis might allow differentiation of the "primary form" of ADHD associated with a decrease of NREM instability from those forms associated with sleep apnea and epileptic activity.

The Relationship Between Sleep, Cognition and Behavior in Children With Newly-Diagnosed Epilepsy Over 36 Months

Introduction

There is substantial evidence that children with epilepsy experience more sleep, behavior and cognitive challenges than children without epilepsy. However, the literature is limited in describing the relationship between sleep, epilepsy, cognition and behavioral challenges and the interactions amongst these factors over time. This study aims to understand the nature and strength of the relationship between sleep, cognition, mood and behavior in children with new-onset epilepsy as assessed by multiple informants at multiple time periods using multiple different dependent measures.

Methods

332 participants (6-16years) were recruited within 6 weeks of their first recognized seizure. The comparison group was comprised of 266 healthy siblings. Participants underwent sleep evaluation by a parent using the Sleep Behavioral Questionnaire (SBQ), cognitive evaluation using a comprehensive neuropsychological test battery, a behavioral evaluation using the Child Behavior Checklist (CBCL from parents and TRF from teachers) and the Children's Depression Inventory (CDI). These evaluations were completed at baseline (B), at 18 months, and at 36 months.

Results

Compared to siblings, children with new-onset epilepsy had more sleep disturbance (SBQ), higher rates of behavioral problems (CBCL and TRF), lower cognitive testing scores, and higher rates of depression; which persisted over the 36-month study. Sleep significantly correlated with behavioral problems, cognitive scores and depression. When divided into categories based of sleep disturbance scores, 39.7% of children with epilepsy experienced "Persistently Abnormal Sleep", while 14.8% experienced "Persistently Normal Sleep". Children with persistently abnormal sleep experienced the highest rates of behavioral problems, depression and cognitive impairment compared to those with persistently normal sleep, regardless of epilepsy syndrome. Younger age of seizure onset, younger age at testing, and lower grade level at baseline were associated with persistently abnormal sleep.

Conclusions

To our knowledge, this is the first demonstration of the nature, strength, reliability, stability and persistence of the relationship between sleep, cognition, and behavioral problems over time in a large cohort of children with newly diagnosed epilepsy, as assessed by multiple informants at different timepoints. The results of this study indicate that children with epilepsy are at a high risk of significant persisting neurobehavioral multimorbidity. Therefore, early screening for these challenges may be essential for optimizing quality of life long-term.

Role of inflammation in childhood epilepsy and ADHD comorbidity

Epilepsy is a heterogeneous disorder that is not limited to experiencing seizures but also includes multiple neuropsychiatric squeal (i.e. attention-deficit/hyperactivity disorder (ADHD), depression and anxiety) that adversely impact a child quality of life. However, the underlying mechanism linking both disorders is not yet thoroughly explored. Our objective was to assess pro-inflammatory cytokines levels in children with seizure controlled epilepsy and explore the association between pro-inflammatory cytokines and the co-occurrence of ADHD in such children. A cross-sectional study included 50 children with controlled epilepsy for at least one year, in addition to 30 neurotypical children as controls. All children were assessed by the Conner parent scale for ADHD. Serum interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) levels were measured and correlated to clinical data. In the present study, 23 out of 50 children with epilepsy also had ADHD (46%). Children with ADHD have been found to have a significantly lower age of onset, longer duration of epilepsy, and a higher serum level of IL-6 and TNF-α than those without ADHD. The Conner's parent rating scale overall total score yielded significant negative correlations with the age of onset of epilepsy and a significant positive correlation with the duration of epilepsy and pro-inflammatory cytokine levels. In addition to active seizures, the presence of elevated circulating inflammation markers may be associated with increased frequency of ADHD in children with epilepsy aged 6-14 years.

Effect of Transcutaneous Vagus Nerve Stimulation at Auricular Concha for Insomnia: A Randomized Clinical Trial

Insomnia inflicts mental burden and decreases physical productivity and affects life quality. Transcutaneous vagus nerve stimulation (ta-VNS) may be an effective treatment option for insomnia. This study aims to evaluate the effect and safety of ta-VNS and compare it with transcutaneous nonvagus nerve stimulation (tn-VNS). A multicenter, randomized, clinical trial was conducted at 3 hospitals in China enrolling 72 insomnia participants from May 2016 to June 2017. Participants were randomly assigned (1 : 1) to receive 40 sessions of ta-VNS or tn-VNS treatment. 63 participants completed the trial. ta-VNS treatment significantly decreased the Pittsburgh Sleep Quality Index score, Epworth Sleepiness Scale score, Flinders Fatigue Scale score, Hamilton Depression Scale score, and Hamilton Anxiety Scale score over 4 weeks compared with those of the baseline. Moreover, it also significantly increased the 36-item Short-Form Health Survey Questionnaire scores compared with that of the baseline. However, it did not show significant differences compared with tn-VNS in changes of primary and secondary outcomes. The incidence of adverse events was low. ta-VNS significantly relieved insomnia over 4 weeks. Moreover, it also alleviated fatigue and improved participants' quality of life as well as other concomitant symptoms such as depression and anxiety. This trial is registered at Chinese Clinical Trial Registry (http://www.chictr.org.cn) with the registration number: ChiCTR-TRC-13003519.

Melatonin inhibits attention-deficit/hyperactivity disorder caused by atopic dermatitis-induced psychological stress in an NC/Nga atopic-like mouse model

Atopic dermatitis (AD) is a chronic inflammatory skin disease with the hallmark characteristics of pruritus, psychological stress, and sleep disturbance, all possibly associated with an increased risk of attention-deficit/hyperactivity disorder (ADHD). However, the etiology of the possible association between AD and ADHD is still not well understood. 2,4-dinitrochlorobenzene or corticosterone was used to evaluate the atopic symptom and its psychologic stress in the atopic mice model. Melatonin, corticotropin-releasing hormone, corticotropin-releasing hormone receptor, urocortin, proopiomelanocortin, adrenocorticotropic hormone, corticosterone, cAMP, cAMP response element-binding protein, dopamine and noradrenaline were analyzed spectrophotometrically, and the expression of dopamine beta-hydroxylase and tyrosine hydroxylase were measured by Western blotting or immunohistochemistry. AD-related psychological stress caused an increase in the levels of dopamine beta-hydroxylase and tyrosine hydroxylase, degradation of melatonin, hyper-activity of the hypothalamic-pituitary-adrenal axis, and dysregulation of dopamine and noradrenaline levels (ADHD phenomena) in the locus coeruleus, prefrontal cortex, and striatum of the AD mouse brain. Notably, melatonin administration inhibited the development of ADHD phenomena and their-related response in the mouse model. This study demonstrated that AD-related psychological stress increased catecholamine dysfunction and accelerated the development of psychiatric comorbidities, such as ADHD.

Sleep Related Epilepsy and Pharmacotherapy: An Insight

In the last several decades, sleep-related epilepsy has drawn considerable attention among epileptologists and neuroscientists in the interest of new paradigms of the disease etiology, pathogenesis and management. Sleep-related epilepsy is nocturnal seizures that manifest solely during the sleep state. Sleep comprises two distinct stages i.e., non-rapid eye movement (NREM) and rapid eye movement (REM) that alternate every 90 min with NREM preceding REM. Current findings indicate that the sleep-related epilepsy manifests predominantly during the synchronized stages of sleep; NREM over REM stage. Sleep related hypermotor epilepsy (SHE), benign partial epilepsy with centrotemporal spikes or benign rolandic epilepsy (BECTS), and Panayiotopoulos Syndrome (PS) are three of the most frequently implicated epilepsies occurring during the sleep state. Although some familial types are described, others are seemingly sporadic occurrences. In the present review, we aim to discuss the predominance of sleep-related epilepsy during NREM, established familial links to the pathogenesis of SHE, BECTS and PS, and highlight the present available pharmacotherapy options.