Sleep in attention-deficit/hyperactivity disorder in children and adults: past, present, and future

The key role of daytime sleepiness in cognitive functioning of adults with attention deficit hyperactivity disorder

Background.

Adults with attention deficit hyperactivity disorder (ADHD) frequently suffer from sleep problems and report high levels of daytime sleepiness compared to neurotypical controls, which has detrimental effect on quality of life.

Methods.

We evaluated daytime sleepiness in adults with ADHD compared to neurotypical controls using an observer-rated sleepiness protocol during the Sustained Attention Response Task as well as electroencephalogram (EEG) slowing, a quantitative electroencephalographic measure collected during a short period of wakeful rest.

Results.

We found that adults with ADHD were significantly sleepier than neurotypical controls during the cognitive task and that this on-task sleepiness contributed to cognitive performance deficits usually attributed to symptoms of ADHD. EEG slowing predicted severity of ADHD symptoms and diagnostic status, and was also related to daytime sleepiness. Frontal EEG slowing as well as increased frontal delta were especially prominent in adults with ADHD. We have validated and adapted an objective observer-rated measure for assessing on-task sleepiness that will contribute to future sleep research in psychology and psychiatry.

Conclusions.

These findings indicate that the cognitive performance deficits routinely attributed to ADHD and often conceptualized as cognitive endophenotypes of ADHD are largely due to on-task sleepiness and not exclusively due to ADHD symptom severity. Daytime sleepiness plays a major role in cognitive functioning of adults with ADHD.

Excessive Daytime Sleepiness Measurements in Children With Attention Deficit Hyperactivity Disorder

Attention deficit hyperactivity disorder (ADHD) is the most commonly diagnosed neurodevelopmental disorder in childhood. It is a heterogeneous disorder in terms of clinical presentation that is probably due to the frequent occurrence of comorbidity. Children with ADHD more frequently report sleep disorders (notably delayed sleep phase syndrome) and excessive daytime sleepiness (EDS) than typically developing children. The aim of this article is to propose a narrative review of the assessment of EDS in the context of ADHD with first a summary of the subjective and objective tools used to measure it. Secondly, perspectives in terms of electroencephalogram (EEG) markers and neurofeedback are proposed. Then, possibilities for new kinds of evaluation are discussed (virtual reality, ecological momentary assessment, etc.). Lastly, we discuss specific clinical situations with EDS in the context of ADHD as links with narcolepsy, the comorbidity with other psychiatric disorders, and the context of sluggish cognitive tempo.

Media Use, Sleep Quality, and ADHD Symptoms in a Community Sample and a Sample of ADHD Patients Aged 8 to 18 Years

Objective: Relationships between sleep, screen-based media, and ADHD symptomatology were investigated using a case- and community-based approach. Method: N = 357 healthy and N = 61 children with ADHD (12.72 ± 2.83 years) completed a sleep and media questionnaire. To measure ADHD symptomatology, parents filled out the Strengths and Weaknesses of ADHD symptoms and Normal behavior (SWAN) scale. Two samples were formed: a matched (N = 61 patients and N = 61 controls) and a community sample (N = 357 healthy participants and N = 20 patients). Results: Compared with controls, participants with ADHD reported delayed sleep onset and more screen time on school days. Adolescent patients showed more behavior promoting delayed sleep phase. In the community sample, media time, sleep deviation, and circadian rhythm were correlated with ADHD symptomatology. Furthermore, media time, sleep-wake behavior, and sleep deviation were predictive of ADHD symptomatology (variance explained = 4%-15%). Conclusion: Longer media time and inadequate sleep-wake behavior increase the risk of ADHD-like symptoms. However, research using objective assessments is needed to disentangle this distinct association and to provide possible directions for intervention.

The Functional Impact of Sleep Disorders in Children With ADHD

Objective: Children with ADHD display higher rates of sleep problems, and both sleep disorders and ADHD have been shown to affect functioning in childhood. The current study examines the frequency and relationship between sleep problems and ADHD, and their impact on quality of life (QoL) and functional impairment. Method: Parents of 192 children with ADHD (M = 10.23 years) completed measures regarding their child's ADHD symptoms (Swanson, Nolan and Pelham [SNAP]), sleep disorders (Pediatric Sleep Questionnaire [PSQ]), QoL (Child Health Illness Profile [CHIP-PE]), and functioning (Weiss Functional Impairment Rating Scale-Parent Report [WFIRS-P]). Results: Common sleep complaints in participants were insomnia, excessive daytime sleepiness (EDS), and variability in sleep schedule. Regression analysis indicated that sleep problems and ADHD symptoms independently predicted lower levels of QoL (ΔR² = .12, p < .001) and social functioning (ΔR² = .12, p < .001). Conclusion: The results suggest that ADHD may coexist with somnolence and that both conditions have a significant impact on a child's functioning and QoL.

Effects of Sleep Extension on Inhibitory Control in Children With ADHD: A Pilot Study

Objective: Children with ADHD often have sleep complaints and cognitive deficits. The aim of this pilot study was to determine whether sleep extension improves inhibitory control, a primary cognitive deficit in ADHD. Method: Children with (n = 11) and without (n = 15) ADHD participated in a within-subject sleep extension intervention that targeted nocturnal sleep duration. Sleep was assessed with actigraphy and polysomnography. Inhibitory control was assessed with a Go/No-Go task. Results: For children without ADHD, there was a significant main effect of time, such that morning inhibitory control was 10% greater than evening inhibitory control. However, inhibitory control did not differ between the baseline and extension conditions in this group. For children with ADHD, although morning inhibitory control did not differ from evening inhibitory control, sleep extension improved inhibitory control by 13% overall. Conclusion: These results suggest that a sleep extension intervention improves inhibitory control in children with ADHD.

The effects of emotional lability, mind wandering and sleep quality on ADHD symptom severity in adults with ADHD

Mind wandering, emotional lability and sleep quality are currently mostly independently investigated but are all interlinked and play a major role is adult attention-deficit/ hyperactivity disorder (ADHD). Emotional lability is a core feature of the disorder, excessive mind wandering has recently been linked to symptoms and impairments of ADHD and poor sleep quality is experienced by a clear majority of adults with ADHD. All three phenomena lead to functional impairment in ADHD, however their relationship to each other and to ADHD symptom severity is not well understood. Here we used serial multiple mediation models to examine the influence of mind wandering, sleep quality and emotional lability on ADHD symptom severity. 81 adults diagnosed with ADHD participated in this study. We found that mind wandering and emotional lability predicted ADHD symptom severity and that mind wandering, emotional lability and sleep quality were all linked and significantly contributed to the symptomatology of adult ADHD. Mind wandering was found to lead to emotional lability which in turn lead to ADHD symptom severity; and poor sleep quality was found to exacerbate mind wandering leading to ADHD symptoms. Future research should employ objective on-task measures of mind wandering, sleepiness and emotional lability to investigate the neural basis of these impairing deficits in ADHD.

Impact of a behavioral intervention, delivered by pediatricians or psychologists, on sleep problems in children with ADHD: a cluster-randomized, translational trial

BACKGROUND

We have demonstrated the efficacy of a brief behavioral intervention for sleep in children with ADHD in a previous randomized controlled trial and now aim to examine whether this intervention is effective and cost-effective when delivered by pediatricians or psychologists in community settings.

METHODS

Translational, cluster-randomized trial of a behavioral intervention versus usual care from 19th January, 2015 to 30th June, 2017. Participants (n = 361) were children aged 5-13 years with ADHD and parent report of a moderate/severe sleep problem who met criteria for American Academy of Sleep Medicine criteria for chronic insomnia disorder, delayed sleep-wake phase disorder, or were experiencing sleep-related anxiety. Participants were randomized at the level of the pediatrician (n = 61) to intervention (n = 183) or usual care (n = 178). Families in the intervention group received two consultations with a pediatrician or a psychologist covering sleep hygiene and tailored behavioral strategies.

RESULTS

In an intention-to-treat analysis, at 3 and 6 months respectively, the proportion of children with moderate to severe sleep problems was lower in the intervention (28.0%, 35.8%) compared with usual care group (55.4%, 60.1%; 3 month: risk ratio (RR): 0.51, 95% CI 0.37, 0.70, p < .001; 6 month: RR: 0.58; 95% CI 0.45, 0.76, p < .001). Intervention children had improvements across multiple Children's Sleep Habits Questionnaire subscales at 3 and 6 months. No benefits of the intervention were observed in other domains. Cost-effectiveness of the intervention was AUD 13 per percentage point reduction in child sleep problem at 3 months.

CONCLUSIONS

A low-cost brief behavioral sleep intervention is effective in improving sleep problems when delivered by community clinicians. Greater sample comorbidity, lower intervention dose or insufficient clinician supervisions may have contributed to the lack benefits seen in our previous trial.

Behavioral and Emotional Disorders and Transportation Noise among Children and Adolescents: A Systematic Review and Meta-Analysis

Children and adolescents may be particularly vulnerable to environmental influences such as noise which can affect mental well-being. The aim of this systematic review was to evaluate the effect of transportation noise on behavioral and emotional disorders in children and adolescents using a meta-analytic approach. Therefore, we searched four databases (Pubmed, Embase, PsychINFO, and PSYNDEX) and grey literature until February of 2019. We identified 14 articles from 10 studies examining the effect of transportation noise exposure on the mental health of children. These studies predominately used the Strength and Difficulties Questionnaire (SDQ) and mainly focused on schoolchildren and adolescents aged 9–10 years and 15–17 years in Europe. Three studies could be included in the meta-analysis. In sum, the odds for hyperactivity/inattention and total difficulties was significantly increased by 11% (Odds Ratio, OR = 1.11 (95% Confidence Interval, CI 1.04–1.19), respectively 9% (95% CI 1.02–1.16) per 10 dB road traffic noise. Thus, we obtained evidence for an effect of road traffic noise on hyperactivity/inattention and total difficulties, although we could consider few studies. Future studies are needed that use similar techniques to assess outcomes and exposures at schools and in homes. This would make it possible to conduct an individual participant data pooled analysis of the data.

Poor Sleep Has Negative Implications for Children With and Without ADHD, but in Different Ways

Background: Sleep problems are commonly reported in attention deficit hyperactivity disorder (ADHD), and are also a familiar characteristic of typical development (TD). We sought to elucidate the relationship between sleep, ADHD trait behaviors, and cognitive inattention, and how it manifests between ADHD and TD children. Participants: Eighteen children diagnosed with ADHD and 20 age-matched TD controls aged 5 to 11 years old participated in the study. Methods: Sleep profiles were assessed using Children's Sleep Habits Questionnaire and actigraphy measures. Behavioral functioning was examined using Conners' Parent Report Scale and attention using the computerized Conners' Continuous Performance Task. Results: We found evidence of (a) poorer sleep quality in the ADHD group, despite no difference in actual sleep time, (b) poor sleep quality in TD children predicting increased ADHD-trait behaviors, despite no association with attention, and (c) a consistent trend for poor sleep quality predicting reduced attentional control in ADHD children, despite no association with behavior. Conclusions: Poor sleep quality affects developmental subgroups in different ways. For ADHD children, poor sleep worsens their predisposed attentional deficit, while for TD children it mimics ADHD behaviors. These findings have important implications for the debate on overdiagnosis of childhood ADHD, and the use of sleep-based interventions. Above all, they highlight the importance of promoting good sleep hygiene in all children.

Disability-Specific Associations with Child Health and Functioning

This study examined the health profile of children with different types of disabilities and explored the disability-specific associations with various types of health and functioning using a large nonclinical sample of children. A cross-sectional school survey was conducted during 2016 and 2017. A total of 4114 children (aged 6⁻18 years) receiving primary or secondary education, or their proxy, in Hong Kong participated in the study. Disabilities were categorized as (a) physical disabilities; (b) learning and developmental disabilities; (c) intellectual disabilities; (d) internalizing disorders or mental illness; and (e) autism spectrum disorder. Health-related quality of life (QoL), sleep-related QoL, activities of daily living (ADL), emotional functioning, and social functioning were assessed and compared between children with disabilities and those without. The results showed that children with disabilities showed poorer physical functioning, health-related QoL, and emotional and social functioning than their counterparts without disabilities. Disability-specific associations with health were found: (a) physical disabilities and intellectual disabilities were associated with greater difficulties in ADL; (b) language impairment and Attention deficit/ hyperactivity disorder (ADHD) were negatively associated with sleep-related QoL; (c) all types of disabilities but hearing impairment were negatively associated with health-related QoL (HRQoL); and (d) language impairment, ADHD, internalizing disorder, as well as autism spectrum disorder were associated with greater abnormal behavioral difficulties. The findings warrant the development of tailor-made intervention programs and give insights to effective resource allocation for the children in need.

Impact of Nasal Septal Surgery on Sleep Quality and Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

To evaluate the effect of nasal septal surgery on quality of life.

METHODS

A total of 49 patients who underwent septoplasty and/or inferior turbinate radiofrequency operations for nasal septal deviation and inferior turbinate hypertrophy were prospectively enrolled in the study. All patients completed the adult attention-deficit/hyperactivity disorder scale (ADHD scale) and Pittsburgh sleep quality index (PSQI) before and after septoplasty. Acoustic rhinometric measurements were also recorded.

RESULTS

Acoustic rhinometric measurements and PSQI showed statistically significant improvement after nasal surgery (P < 0.05), but no statistically significant difference was present between pre- and postoperative ADHD scores (P > 0.05).

CONCLUSION

Besides the functional improvement of septoplasty, a long-lasting improvement in the quality of life is observed in patients with that undergo this surgery.

Positive emotional attention bias in young children with symptoms of ADHD

Children with attention-deficit/hyperactivity disorder (ADHD) often experience emotional dysregulation. Dysregulation can arise from heightened attention to emotional stimuli. Emotional attention biases are associated with a number of adverse socioemotional outcomes including reward sensitivity and externalizing behaviors. As reward sensitivity and externalizing behaviors are common in children with ADHD, the aim of the current study was to determine whether emotional attention biases are evident in young children with clinically significant ADHD symptoms. To test this, children with (n = 18) and without (n = 15) symptoms of ADHD were tested on a Dot Probe task. Provided recent evidence that emotional attention biases are attenuated by sleep, the task was performed before and after overnight sleep. Children with ADHD symptoms displayed positive, but not negative, attention biases at both time points, whereas typically developing children did not preferentially attend toward or away from positive or negative stimuli. Sleep did not alter attention biases in either group. Collectively, these results indicate that children with ADHD symptoms have stable, positive attention biases.

Attention-deficit hyperactivity disorder in ancient Greece: The Obtuse Man of Theophrastus

We present an ancient Greek description written by the philosopher Theophrastus in his classic book ' Characters' comparable with modern attention-deficit hyperactivity disorder. The arguments are based in one chapter of this book-The Obtuse Man-presenting features of a character closely resembling the modern description of attention-deficit hyperactivity disorder. In a free comparative exercise, we compared Theophrastus descriptions with modern Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) attention-deficit hyperactivity disorder symptoms. The sentences describing The Obtuse Man written by Theophrastus are similar to several symptoms of attention-deficit hyperactivity disorder and he would probably be currently diagnosed with this disorder as an adult. To our knowledge, this is the oldest description compatible with the current conception of attention-deficit hyperactivity disorder in adults in the Western literature. Differently than the moralistic view of ancient Greece regarding those symptoms, the medical attention-deficit hyperactivity disorder conception may be advantageous to patients since it might reduce prejudice and allow individuals to seek treatment.

The Impact of Sleep Restriction on Daytime Functioning in School-Age Children With and Without ADHD: A Narrative Review of the Literature

The purpose of this narrative review was to synthesize the existing literature on the impact of sleep on daytime functioning in both typically developing (TD) children and children with attention-deficit/hyperactivity disorder (ADHD). Correlational studies in children suggest that insufficient sleep and impaired daytime functioning are significantly associated; however, this does not address the causal relationships between sleep and daytime functioning. The review results indicated that there is limited experimental sleep manipulation research in children. In the eight studies that employed experimental methods to examine sleep restriction, the consequences of insufficient sleep were greatest for attention and inconsistent for other domains, such as cognition and emotion regulation. Despite the significant co-occurrence of ADHD and sleep problems, the experimental sleep research focused on the daytime impact of shorter sleep in children with ADHD is extremely limited and as such more research is needed.

The Association Between Insomnia and Sleep Duration in Adults With Attention-Deficit Hyperactivity Disorder: Results From a General Population Study

STUDY OBJECTIVES

Insomnia and short or long sleep duration are important comorbid conditions in adults with attention-deficit hyperactivity disorder (ADHD), but reports of the association vary. In a general population study, we evaluated the relationship between ADHD symptom severity, insomnia symptoms, and sleep duration in adults.

METHODS

Data were from the third wave of the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2; n = 4,618). ADHD symptom severity and symptom dimensions (hyperactivity and inattention) were assessed using the Adult ADHD Self-Report Scale screener. Self-reported insomnia symptoms (Insomnia Rating Scale; IRS) were defined as clinically relevant if IRS ≥ 9. Self-reported short sleep duration was defined as ≤ 6 hours, and long sleep duration as ≥ 10 hours.

RESULTS

Within the group with clinically relevant ADHD symptoms, 43% reported significant insomnia symptoms (odds ratio [OR] = 2.66, 95% confidence interval [CI] 1.74-4.07); 41% short sleep duration (relative risk ratio [RRR] = 1.94, 95% CI 1.31-2.85) and 6% long sleep (RRR = 5.87, 95% CI 1.97-17.45). Increased inattention symptoms were associated with IRS ≥ 9, short and long sleep duration in fully adjusted models (OR = 1.10, 95% CI 1.06-1.14; RRR = 1.06, 95% CI 1.02-1.09; RRR = 1.16, 95% CI 1.05-1.28, respectively). Increased hyperactivity symptoms were associated with IRS ≥ 9 (OR = 1.17, 95% CI 1.11-1.23) and short sleep duration (RRR = 1.12, 95% CI 1.05-1.19).

CONCLUSIONS

Both clinically significant ADHD symptoms and inattention and hyperactivity symptom dimensions were consistently associated with insomnia symptoms and altered sleep duration. These associations confirm that sleep disturbances should be assessed and given appropriate clinical attention in adults with ADHD.

The impact of comorbid mental health symptoms and sex on sleep functioning in children with ADHD

Children with attention-deficit/hyperactivity disorder (ADHD) display more sleep problems than their peers, but it remains unclear whether comorbid mental health symptoms [i.e., anxiety, depression, oppositional-defiant disorder (ODD)] are uniquely related to sleep functioning. It is also largely unknown whether boys and girls with ADHD differ in their sleep functioning. This study (1) examined whether boys or girls with ADHD differ in their sleep functioning, (2) evaluated comorbid symptoms as uniquely related to sleep functioning domains, and (3) explored whether sex moderated associations between comorbid symptoms and sleep. Participants were 181 children (ages 7-13; 69% male; 82% White) diagnosed with ADHD. Parents completed measures assessing their child's ADHD symptoms, comorbid symptoms, and sleep functioning. Girls had poorer sleep functioning than boys across most sleep functioning domains. Sixty percent of children met cutoff criteria for having sleep problems, though rates differed significantly between girls (75%) and boys (53%). No differences in rates of sleep problems were found between ADHD subtypes/presentations or between younger and older children. In path models including ADHD and comorbid symptom dimensions, anxiety symptoms were uniquely associated with increased bedtime resistance and sleep anxiety, ADHD hyperactive-impulsive symptoms were associated with more night wakings and more parasomnia behaviors, and ODD and depressive symptoms were associated with shorter sleep duration. Depression was also uniquely associated with increased daytime sleepiness and overall sleep problems. Sex did not moderate associations between comorbid symptoms and sleep problems. This study provides important preliminary evidence that girls with ADHD experience more sleep problems than boys with ADHD. Findings also demonstrate that the associations between comorbid symptoms and sleep functioning in children with ADHD vary based on both the specific symptoms and sleep domains examined.

Brain arousal regulation in adults with attention-deficit/hyperactivity disorder (ADHD)

The main aim of the current study was to test the hypothesis that adult patients with attention-deficit/hyperactivity disorder (ADHD) have less stable brain arousal regulation than healthy controls. We objectively assessed brain arousal regulation using the Vigilance Algorithm Leipzig (VIGALL 2.1) to analyze 15-min resting EEG data of thirty-three ADHD patients and thirty-five matched controls. Based on automatically classified 1-s segments we computed mean EEG-vigilance (indexing arousal level) and arousal stability score (indexing arousal regulation). Adult ADHD patients showed significantly lower arousal levels and significantly less stable brain arousal regulation than controls. Multiple regression analysis indicated that arousal regulation (i.e., arousal stability score) predicted the retrospectively-assessed severity of childhood ADHD symptoms, supporting the trait aspect of brain arousal regulation. Our findings support the arousal regulation model of ADHD, which interprets hyperactivity and sensation seeking as an autoregulatory reaction to an unstable regulation of brain arousal. EEG-based arousal parameters may be candidate biomarkers for adult ADHD.

Association Between Restless Legs Syndrome and Adult ADHD in a German Community-Based Sample

OBJECTIVE

Previous research in clinical samples indicated a significant association between ADHD and restless legs syndrome (RLS). The present study examined the association between adult ADHD and RLS in the German population.

METHOD

Self-rating instruments to assess RLS, childhood ADHD, and adult ADHD were administered to a community-based sample ( N = 1,632). In addition, current depression and anxiety, sleep disturbances, weight, and height were assessed by self-report.

RESULTS

Adult ADHD was associated with statistically significant increases in the odds of meeting diagnostic criteria for RLS even when adjusting for potential confounding variables such as weight (odds ratio [OR] = 3.18, 95% confidence interval [CI] = [1.29, 7.63], p< .001). However, the association did not hold true after adjusting for the presence of sleep disturbances (OR = 2.02, 95% CI = [0.82, 4.96], p = .13).

CONCLUSION

The findings suggest a strong link between RLS and adult ADHD symptoms. Clinicians should be aware of RLS among adult ADHD patients, especially as there might be a negative interactive effect.

Adult ADHD and Comorbid Somatic Disease: A Systematic Literature Review

OBJECTIVE

To systematically review, synthesize, and appraise available evidence, connecting adult ADHD with somatic disease.

METHOD

Embase, Psychinfo, and Medline databases were searched for studies published from 1994 to 2015 addressing adult ADHD and somatic comorbidity. Somatic conditions were classified according to International Classification of Diseases (ICD-10) codes. Levels of evidence were graded as inconclusive, tentative, or well documented.

RESULTS

Most of the 126 studies included in the qualitative synthesis were small and of modest quality. Obesity, sleep disorders, and asthma were well-documented comorbidities in adult ADHD. Tentative evidence was found for an association between adult ADHD and migraine and celiac disease. In a large health registry study, cardiovascular disease was not associated with adult ADHD.

CONCLUSION

There are few large systematic studies using standardized diagnostic criteria evaluating adult ADHD and somatic comorbidities. Significant associations are found between adult ADHD and several somatic diseases, and these are important to consider when assessing and treating either adult ADHD or the somatic diseases.

Effect on Primary Sleep Disorders When Children With ADHD Are Administered Guanfacine Extended Release

OBJECTIVE

To evaluate children with ADHD and sleep problems with polysomnography (PSG) after guanfacine extended-release (GXR) administration.

METHOD

Double-blind, randomized, placebo-controlled study was terminated early due to treatment-emergent concerns after enrolling 29 children aged 6 to 12 years. After >4 weeks dose adjustment and >1 week dose stabilization, 11 children received GXR and 16 controls underwent analyses with PSG.

RESULTS

Although GXR improved ADHD symptoms, the primary outcome variable, total sleep time, was shorter in contrast to placebo (-57.32, SD = 89.17 vs. +31.32, SD = 59.54 min, p = .005). Increased time awake after sleep onset per hour of sleep was the primary factor for the reduction. Although rapid eye movement (REM), non-REM, and N3/slow wave sleep times were reduced, these were proportional to the overall sleep reduction. Sedation was common with GXR (73% vs. 6%).

CONCLUSION

Morning-administered GXR resulted in decreased sleep and may contribute to sedation.

Leg Movement Activity During Sleep in Adults With Attention-Deficit/Hyperactivity Disorder

Objectives: To conduct a first detailed analysis of the pattern of leg movement (LM) activity during sleep in adult subjects with Attention-Deficit/Hyperactivity Disorder (ADHD) compared to healthy controls. Methods: Fifteen ADHD patients and 18 control subjects underwent an in-lab polysomnographic sleep study. The periodic character of LMs was evaluated with established markers of "periodicity," i.e., the periodicity index, intermovement intervals, and time distribution of LM during sleep, in addition to standard parameters such as the periodic leg movement during sleep index (PLMSI) and the periodic leg movement during sleep arousal index (PLMSAI). Subjective sleep and psychiatric symptoms were assessed using several, self-administered, screening questionnaires. Results: Objective sleep parameters from the baseline night did not significantly differ between ADHD and control subjects, except for a longer sleep latency (SL), a longer duration of the periodic leg movements during sleep (PLMS) in REM sleep and a higher PLMSI also in REM sleep. Data from the sleep questionnaires showed perception of poor sleep quality in ADHD patients. Conclusions: Leg movements during sleep in ADHD adults are not significantly more frequent than in healthy controls and the nocturnal motor events do not show an increased periodicity in these patients. The non-periodic character of LMs in ADHD has already been shown in children and seems to differentiate ADHD from other pathophysiological related conditions like restless legs syndrome (RLS) or periodic limb movement disorder (PLMD). The reduced subjective sleep quality reported by ADHD adults contrasted with the normal objective polysomnographic parameters, which could suggest a sleep-state misperception in these individuals or more subtle sleep abnormalities not picked up by the traditional sleep staging.

Cognitive and Behavioral Consequences of Sleep Disordered Breathing in Children

There is now a plethora of evidence that children with sleep disordered breathing (SDB) show deficits in neurocognitive performance, behavioral impairments, and school performance. The following review will focus on the neurobehavioral impacts of SDB, pediatric sleep investigation challenges, potential mechanisms of behavioral and cognitive deficits in children with SDB, and the impact of SDB treatment.

Developmental Ethanol-Induced Sleep Fragmentation, Behavioral Hyperactivity, Cognitive Impairment and Parvalbumin Cell Loss are Prevented by Lithium Co-treatment

Developmental ethanol exposure is a well-known cause of lifelong cognitive deficits, behavioral hyperactivity, emotional dysregulation, and more. In healthy adults, sleep is thought to have a critical involvement in each of these processes. Our previous work has demonstrated that some aspects of cognitive impairment in adult mice exposed at postnatal day 7 (P7) to ethanol (EtOH) correlate with slow-wave sleep (SWS) fragmentation (Wilson et al., 2016). We and others have also previously demonstrated that co-treatment with LiCl on the day of EtOH exposure prevents many of the anatomical and physiological impairments observed in adults. Here we explored cognitive function, diurnal rhythms (activity, temperature), SWS, and parvalbumin (PV) and perineuronal net (PNN)-positive cell densities in adult mice that had received a single day of EtOH exposure on P7 and saline-treated littermate controls. Half of the animals also received a LiCl injection on P7. The results suggest that developmental EtOH resulted in adult behavioral hyperactivity, cognitive impairment, and reduced SWS compared to saline controls. Both of these effects were reduced by LiCl treatment on the day of EtOH exposure. Finally, developmental EtOH resulted in decreased PV/PNN-expressing cells in retrosplenial (RS) cortex and dorsal CA3 hippocampus at P90. As with sleep and behavioral activity, LiCl treatment reduced this decrease in PV expression. Together, these results further clarify the long-lasting effects of developmental EtOH on adult behavior, physiology, and anatomy. Furthermore, they demonstrate the neuroprotective effects of LiCl co-treatment on this wide range of developmental EtOH's long-lasting consequences.

Adult Attention-Deficit/Hyperactivity Disorder (ADHD) and Insomnia: an Update of the Literature

PURPOSE OF REVIEW

Insomnia is diagnosed when there is dissatisfaction with sleep quantity or quality. It has a prevalence in the general population ranging from 31 to 56%. Insomnia has previously been associated with adult attention-deficit/hyperactivity disorder (ADHD). In this review, we address three topics: (1) the cross-sectional relationship between ADHD and insomnia in adulthood, (2) the longitudinal relationship between ADHD and insomnia, and (3) insomnia as a side effect of pharmacological treatments for adult ADHD.

RECENT FINDINGS

Three cross-sectional, clinical, and population studies report a prevalence of insomnia in ADHD adults ranging from 43 to 80%. Longitudinal evidence for a link between childhood-onset ADHD and insomnia at later age is mixed, with one study confirming and another study not supporting such a longitudinal association. In randomized, placebo-controlled trials, insomnia is reported significantly more often in the treatment arm than in the placebo arm. In varying percentages of trial participants, insomnia is a treatment-emergent adverse effect in triple-bead mixed amphetamine salts (40-45%), dasotraline (35-45%), lisdexamfetamine (10-19%), and extended-release methylphenidate (11%). Ten to seventeen percent of subjects in placebo-controlled trials of atomoxetine report insomnia, possibly related to poor metabolizer status. The mechanisms explaining the relationship between ADHD and sleep problems are incompletely understood, but both genetic and non-shared environmental influences may be involved. Adults with ADHD should be assessed for insomnia, which is frequently comorbid, and both conditions should be treated.

Attention deficit hyperactivity disorder symptom severity and sleep problems in adult participants of the Netherlands sleep registry

BACKGROUND

We examined whether current overall attention deficit hyperactivity disorder (ADHD), inattention, or hyperactivity symptom severities are associated with the current presence and persistent history of sleep problems.

METHODS

N = 942 participants of the Netherlands Sleep Registry filled out online several validated questionnaires. Regression analyses were performed to assess the association between (1) current overall ADHD symptom severity and the current presence of sleep problems, (2) current ADHD symptom-severity groups and the persistent history of sleep problems, and (3) current inattention or hyperactivity symptom severities and the current presence of sleep problems.

RESULTS

(1) Current overall ADHD symptom severity was associated with the odds of suffering from probable obstructive sleep apnea syndrome (OSAS), restless legs syndrome (RLS), periodic limb movement disorder (PLMD), insomnia disorder (ID) with predominant difficulties initiating sleep (DIS) and maintaining sleep (DMS), but not with the odds of suffering from narcolepsy or ID with predominant early-morning awakening (EMA). Current overall ADHD symptom severity was also associated with an extreme evening chronotype but not with short sleep. (2) The group with the most severe current ADHD symptoms was more likely to have a history of persistent OSAS, RLS, and ID. (3) The severity of symptoms of hyperactivity, but not of inattention, was specifically associated with probable RLS, PLMD, ID with DIS or DMS, and short sleep. Inattention symptom severity was only related to the probability of being an extreme evening chronotype.

CONCLUSION

ADHD severity, especially the severity of hyperactivity, is associated with the current presence and persistent history of sleep problems.

Adults with Attention Deficit Hyperactivity Disorder Report High Symptom Levels of Troubled Sleep, Restless Legs, and Cataplexy

Objective: To compare the occurrence of a spectrum of different self-reported sleep problems in adults with ADHD and a control group, and to study the impact of current ADHD medication use and clinical ADHD subtype.

Method: Cross-sectional study of 268 clinically ascertained adult ADHD patients (DSM-IV criteria) and 202 randomly selected controls. Sleep problems were self-reported using validated questions, partly from Global Sleep Assessment Questionnaire.

Results: ADHD patients reported more sleep problems than controls: Lifetime occurrence of sleep problems (82.6 vs. 36.5%), hypnotics use (61.4 vs. 20.2%), current sleep duration below 6 h (26.6 vs. 7.6%), and symptoms/signs during the past 4 weeks of excessive daytime sleepiness, cataplexy, loud snoring, breathing pauses during sleep, restless legs, and periodic limb movements in sleep (significant odds ratios ranged from 1.82 to 14.55). Current ADHD medication use was associated with less cataplexy compared with not using medication. Patients with inattentive subtype reported better sleep quality and less restless legs than patients with hyperactive/impulsive subtypes.

Conclusions: Adults with ADHD reported a very high occurrence of many different self-reported sleep problems, underlining the importance of screening for sleep disorders. Among the ADHD patients, medication use was not associated with more sleep-related symptoms, but in fact less cataplexy. When comparing ADHD subtypes, the inattentive subtype was associated with less sleep problems.

Characteristics of sleep in socially vulnerable adolescents

IMPORTANCE

This study may help understand the effects of an unfavorable environment in sleep quality of adolescents.

OBJECTIVE

To investigate sleep quality in socially vulnerable adolescents, correlating the results with cognitive problems and attention deficit/hyperactivity disorder, and assessing the effectiveness of sleep hygiene and an educational intervention.

DESIGN

Cross-sectional and interventional study.

SETTING

an educational charitable center supported by a Catholic institution, in Porto Alegre, southern Brazil.

PARTICIPANTS

125 male and female high school students.

INTERVENTIONS

As first step the subjects were administered specific questionnaires, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS), followed by an educational activity that was combined with an unblinded, randomized interventional study. Next, a cross-sectional study was conducted to determine the influence of cognition and ADHD on the sleep.

MAIN OUTCOME AND MEASURES

Sleep was evaluated using PSQI and ESS. Cognitive assessment was based on the Wechsler Abbreviated Scale of Intelligence and ADHD by a clinical interview the Multimodal Treatment Study for ADHD (MTA-SNAP-IV).

RESULTS

The average duration of sleep per night were 6 h 30 m. 80% of the sample presented sleep complains. Of these, 44% had excessive daytime sleepiness and 69.6% had poor sleep quality related to use of electronic media, environmental violence, and emotional issues. There were no significant associations between sleep problems and cognitive problems or ADHD. Sleep quality improved in 17% of the 53 students with previous sleep complains who participated in any of the two interventions.

CONCLUSIONS

A high prevalence of sleep deprivation and sleep complains was found in the study sample. The interventions showed some positive effects on the improvement of sleep quality.

Safety, Tolerability and Efficacy of Drugs for Treating Behavioural Insomnia in Children with Attention-Deficit/Hyperactivity Disorder: A Systematic Review with Methodological Quality Assessment

OBJECTIVE

A large proportion of paediatric patients with attention-deficit/hyperactivity disorder (ADHD) have associated sleep problems which not only affect the child's wellbeing but also impact family functioning. Management of sleep problems is consequently an important aspect of overall ADHD management in paediatric patients. Although some drugs are being used off-label for the management of paediatric insomnia, there is scant clinical evidence supporting their use. Our aim was to identify and assess the quality of published studies reporting the safety, tolerability and efficacy of drugs used for treating behavioural insomnia in children with ADHD.

METHODS

After an initial screen to determine which drugs were most commonly used, we conducted a systematic review of English-language publications from searches of PubMed, EMBASE, PsycINFO and two trial register databases to February 2017, using keywords 'clonidine', 'melatonin', 'zolpidem', 'eszopiclone', 'L-theanine', 'guanfacine', 'ADHD', 'sleep disorder' and 'children'. For quality assessment of included studies, we used the CONSORT checklist for randomised control trials (RCTs) and the Downs and Black checklist for non-RCTs.

RESULTS

Twelve studies were included. Two case series for clonidine, two RCTs and four observational studies for melatonin and one RCT each for zolpidem, eszopiclone, L-theanine and guanfacine. Of the 12 included studies, only one on eszopiclone scored excellent for quality. The quality of the rest of the studies varied from moderate to low. For clonidine, melatonin and L-theanine, improvements in sleep-onset latency and total sleep duration were reported; however, zolpidem, eszopiclone and guanfacine failed to show any improvement when compared with placebo. Clonidine, melatonin, L-theanine, eszopiclone and guanfacine were well tolerated with mild to moderate adverse events; zolpidem was associated with neuropsychiatric adverse effects.

CONCLUSION

There is generally poor evidence for prescribing drugs for behavioural insomnia in children with ADHD. Further controlled studies are warranted.

ADHD and Sleep Quality: Longitudinal Analyses From Childhood to Early Adulthood in a Twin Cohort

Attention-deficit/hyperactivity disorder (ADHD) is associated with poor sleep quality, but there is more to learn about the longitudinal association and aetiology of this association. We investigated the following: (a) Is there an association between childhood ADHD and poor sleep quality in young adulthood? (b) Is this driven by the long-term effects of childhood ADHD or concurrent associations with ADHD in young adulthood? (c) To what extent do genetic and environmental influences explain the overlap between symptoms of ADHD and poor sleep quality? Participants were from the Environmental Risk Longitudinal Twin Study of 2,232 twin children born in the United Kingdom in 1994-1995. We ascertained ADHD diagnoses at ages 5, 7, 10, 12, and 18. We assessed sleep quality using the Pittsburgh Sleep Quality Index at age 18. We used regression models to examine longitudinal associations and bivariate twin modelling to test genetic and environmental influences. Children with ADHD had poorer sleep quality in young adulthood, but only if their ADHD persisted. Adults with ADHD had more sleep problems than those without ADHD, over and above psychiatric comorbidity and maternal insomnia. ADHD and sleep problems in young adulthood were associated because of genetic (55%) and nonshared environmental influences (45%). Should ADHD remit, children with ADHD do not appear to have an increased risk of later sleep problems. Good quality sleep is important for multiple areas of functioning, and a better understanding of why adults with ADHD have poorer sleep quality will further the goal of improving treatments.

REM theta activity enhances inhibitory control in typically developing children but not children with ADHD symptoms

Sleep disturbances impair cognitive functioning in typically developing populations. Children with attention-deficit/hyperactivity disorder (ADHD), a disorder characterized by impaired inhibitory control and attention, commonly experience sleep disturbances. Whether inhibitory impairments are related to sleep deficits in children with ADHD is unknown. Children with ADHD (n = 18; M _age = 6.70 years) and typically developing controls (n = 15; M _age = 6.73 years) completed a Go/No-Go task to measure inhibitory control and sustained attention before and after polysomnography-monitored overnight sleep. Inhibitory control and sustained attention were improved following overnight sleep in typically developing children. Moreover, morning inhibitory control was positively correlated with rapid eye movement (REM) theta activity in this group. Although REM theta activity was greater in children with ADHD compared to typically developing children, it was functionally insignificant. Neither inhibitory control nor sustained attention was improved following overnight sleep in children with ADHD symptoms, and neither of these behaviors was associated with REM theta activity in this group. Taken together, these results indicate that elevated REM theta activity may be functionally related to ADHD symptomology, possibly reflecting delayed cortical maturation.

Nightmare frequency in adults with attention-deficit hyperactivity disorder

Nightmare frequency in adult ADHD patients has not yet been studied systematically. In a sample of 65 patients, it could be shown that nightmare frequency was elevated in ADHD patients compared to a sample representative for Germany. Frequent nightmares (once a week or more often) were reported by 4.62 % of the patients and 1.77 % of the controls. This increase was neither explained by the increased dream recall in general nor by the presence of a comorbid mental disorder. Questions about nightmares should be included in the diagnostic procedures for ADHD patients, and it should be tested whether well-established nightmare treatment strategies like imagery rehearsal treatment might be beneficial to those patients with nightmares.

Assessment of Wakefulness and Brain Arousal Regulation in Psychiatric Research

During the last few decades, much knowledge has been gained about sleep being a heterogeneous condition with several distinct sleep stages that represent fundamentally different physiological states. The same applies for the wake state which also comprises distinct global functional states (called vigilance stages). However, various terms and concepts have been introduced describing different aspects of wakefulness, and accordingly several methods of assessment exist, e.g. sleep laboratory assessments (Multiple Sleep Latency Test, Maintenance of Wakefulness Test), questionnaires (Epworth Sleepiness Scale, Karolinska Sleepiness Scale), behavioural tasks (Psychomotor Vigilance Test) or electroencephalography (EEG)-based assessments (Alpha Attenuation Test, Karolinska Drowsiness Test). Furthermore, several theoretical concepts about the regulation of sleep and wakefulness have been put forward, and physiological correlates have been identified. Most relevant for healthy functioning is the regulation of brain arousal and the adaption of wakefulness to the environmental and situational needs so that the optimal balance between energy conservation and responsiveness can be obtained. Since one approach to the assessment of brain arousal regulation is the classification of EEG vigilance stages, a computer-based algorithm (Vigilance Algorithm Leipzig) has been introduced, allowing classification of EEG vigilance stages in EEG recordings under resting conditions. The time course of EEG vigilance stages in EEGs of 15-20 min duration allows estimation of the individual arousal regulation (hyperstable, adaptive, or unstable vigilance pattern). The vigilance model of affective disorders and attention-deficit/hyperactivity disorder links a disturbed arousal regulation to the pathogenesis of psychiatric disorders and accordingly helps to explain and possibly also predict treatment effects of pharmacological and non-pharmacological interventions for these conditions.

An Intervention to Promote Sleep and Reduce ADHD Symptoms

OBJECTIVE

To determine the effect of a sleep hygiene education module and prescriptive sleep routine for children ages 5 through 11 years with attention deficit hyperactivity disorder (ADHD).

METHODS

The 20-week pilot project used a pre-/posttest design to assess sleep and ADHD symptoms. The Child Sleep Habits Questionnaire (CHSQ) and Vanderbilt Assessment Scale-Parent Form survey were provided to assess sleep and ADHD behaviors of participants at baseline and 6 weeks after implementation of the sleep hygiene routine. Fifty-three children participated in the project. Of these, 23 scored 42 or greater on the CHSQ, indicating a sleep disorder, and received the intervention.

RESULTS

The CHSQ and Vanderbilt scores indicated a significant improvement in sleep quality and reduction in ADHD symptoms after implementation of the sleep hygiene routine (CHSQ: p < .001, d = .928; Vanderbilt Questions 1-9: p < .001, d = .473; Vanderbilt Questions 10-18: p = .004; d = .329).

CONCLUSION

A provider-instructed sleep hygiene routine in children with ADHD improves sleep quality and reduces ADHD symptoms.

School Maladjustment and External Locus of Control Predict the Daytime Sleepiness of College Students With ADHD

OBJECTIVE

The primary aim of this study was to evaluate whether school maladjustment longitudinally predicts the daytime sleepiness of college students with ADHD above and beyond symptoms of ADHD and to determine whether internalizing dimensions mediate the relationship between maladjustment and sleepiness.

METHOD

A prospective longitudinal study of 59 college students comprehensively diagnosed with ADHD who completed ratings at the beginning, middle, and end of the school year.

RESULTS

School maladjustment at the beginning of the year significantly predicted daytime sleepiness at the end of the year above and beyond symptoms of ADHD. Locus of control mediated the relationship between maladjustment and daytime sleepiness.

CONCLUSION

The significant school maladjustment difficulties that students with ADHD experience following the transition to college may lead to the development of problems with daytime sleepiness, particularly for those students with high external locus of control. This pattern is likely reciprocal, whereby sleep problems in turn result in greater school impairment, reinforcing the idea that life events are outside of one's control.

Associations of pineal volume, chronotype and symptom severity in adults with attention deficit hyperactivity disorder and healthy controls

The pineal gland, as part of the human epithalamus, is the main production site of peripheral melatonin, which promotes the modulation of sleep patterns, circadian rhythms and circadian preferences (morningness vs. eveningness). The present study analyses the pineal gland volume (PGV) and its association with circadian preferences and symptom severity in adult ADHD patients compared to healthy controls. PGV was determined manually using high-resolution 3T MRI (T1-magnetization prepared rapid gradient echo) in medication free adult ADHD patients (N=74) compared to healthy controls (N=86). Moreover, the Morningness-Eveningness Questionnaire (MEQ), the ADHD Diagnostic Checklist and the Wender-Utah Rating Scale were conducted. PGV differed between both groups (patients: 59.9±33.8mm(3); healthy controls: 71.4±27.2mm(3), P=0.04). In ADHD patients, more eveningness types were revealed (patients: 29%; healthy controls: 17%; P=0.05) and sum scores of the MEQ were lower (patients: 45.8±11.5; healthy controls 67.2±10.1; P<0.001). Multiple regression analyses indicated a positive correlation of PGV and MEQ scores in ADHD (β=0.856, P=0.003) but not in healthy controls (β=0.054, P=0.688). Patients' MEQ scores (β=-0.473, P=0.003) were negatively correlated to ADHD symptoms. The present results suggest a linkage between the PGV and circadian preference in adults with ADHD and an association of the circadian preference to symptom severity. This may facilitate the development of new chronobiological treatment approaches for the add-on treatment in ADHD.

Sleep and melatonin secretion abnormalities in children and adolescents with fetal alcohol spectrum disorders

OBJECTIVES

Caregivers describe significant sleep disturbances in the vast majority of children and adolescents, which is diagnosed as fetal alcohol spectrum disorders (FASD), but objective data on sleep disorders in this population are almost completely lacking. Animal models suggest that intrauterine alcohol exposure may disrupt sleep wake patterns, cause sleep fragmentation, and specifically affect the suprachiasmatic nucleus, thus disrupting melatonin secretion. The objective of this pioneering study was to evaluate sleep and melatonin abnormalities in children with FASD using objective, gold-standard measures.

METHODS

Children and adolescents (N = 36, 6-18 years) with FASD participated in clinical assessments by sleep specialists, overnight polysomnography (PSG), and a dim light melatonin onset (DLMO) test in a pediatric sleep laboratory. PSG was analyzed according to standardized scoring guidelines and sleep architecture was compared with normative data. DLMOs were determined and melatonin secretion curves were evaluated qualitatively to classify melatonin profiles. Sleep disorders were evaluated according to international diagnostic criteria.

RESULTS

There was a high prevalence (58%) of sleep disorders. The most common sleep problems were parasomnias (27.9%) and insomnia (16.8%). The sleep studies showed lower than normal sleep efficiency and high rates of sleep fragmentation. Most participants (79%) had an abnormal melatonin profile.

CONCLUSIONS

This study led to the recognition that both sleep and melatonin secretion abnormalities are present in children with FASD. Therefore, to be effective in managing the sleep problems in children with FASD, one needs to consider both the sleep per se and a possible malfunction of the circadian regulation.

The ADHD Concomitant Difficulties Scale (ADHD-CDS), a Brief Scale to Measure Comorbidity Associated to ADHD

Introduction: Although the critical feature of attention-deficit/hyperactivity disorder (ADHD) is a persistent pattern of inattention and/or hyperactivity/impulsivity behavior, the disorder is clinically heterogeneous, and concomitant difficulties are common. Children with ADHD are at increased risk for experiencing lifelong impairments in multiple domains of daily functioning. In the present study we aimed to build a brief ADHD impairment-related tool -ADHD concomitant difficulties scale (ADHD-CDS)- to assess the presence of some of the most important comorbidities that usually appear associated with ADHD such as emotional/motivational management, fine motor coordination, problem-solving/management of time, disruptive behavior, sleep habits, academic achievement and quality of life. The two main objectives of the study were (i) to discriminate those profiles with several and important ADHD functional difficulties and (ii) to create a brief clinical tool that fosters a comprehensive evaluation process and can be easily used by clinicians.

Methods: The total sample included 399 parents of children with ADHD aged 6–18 years (M = 11.65; SD = 3.1; 280 males) and 297 parents of children without a diagnosis of ADHD (M = 10.91; SD = 3.2; 149 male). The scale construction followed an item improved sequential process.

Results: Factor analysis showed a 13-item single factor model with good fit indices. Higher scores on inattention predicted higher scores on ADHD-CDS for both the clinical sample (β = 0.50; p < 0.001) and the whole sample (β = 0.85; p < 0.001). The ROC curve for the ADHD-CDS (against the ADHD diagnostic status) gave an area under the curve (AUC) of.979 (95%, CI = [0.969, 0.990]).

Discussion: The ADHD-CDS has shown preliminary adequate psychometric properties, with high convergent validity and good sensitivity for different ADHD profiles, which makes it a potentially appropriate and brief instrument that may be easily used by clinicians, researchers, and health professionals in dealing with ADHD.

Excessive daytime sleepiness in adults with possible attention deficit/hyperactivity disorder (ADHD): a web-based cross-sectional study

OBJECTIVES

Arousal dysregulation has been speculated to be involved in the pathological mechanism of attention deficit/hyperactivity disorder (ADHD). However, there has been no epidemiological study assessing the real condition of excessive daytime sleepiness (EDS) in adults with ADHD. This study investigated the prevalence of EDS and the relationship between sleepiness and ADHD symptoms in adults with possible ADHD.

METHODS

An observational, cross-sectional, web-based study was performed. Participants were 9822 Japanese adults aged 20-69 years who completed an Internet-based questionnaire that assessed ADHD symptoms, autistic traits, depressive symptoms, chronotype, sleepiness, and sleep disturbances.

RESULTS

Participants with possible ADHD were more likely than non-ADHD participants to have an evening chronotype and experience depressive symptoms, sleepiness, and sleep disturbances. The rates of having moderate and severe sleepiness in the possible ADHD group were higher than those in the non-ADHD group. Hierarchical logistic regression analyses revealed that the presence of ADHD symptoms was independently associated with EDS even after adjusting for factors related to the presence of sleepiness. When examining inattention and hyperactivity scores among participants with possible ADHD, the inattention score was significantly higher in the severe EDS group compared with the moderate and non-EDS groups.

CONCLUSIONS

EDS was relatively common in adults with possible ADHD. ADHD symptoms, especially inattentiveness, were associated with the formation of EDS in this population.

Effects of Methylphenidate on Sleep Functioning in Children with Attention-Deficit/Hyperactivity Disorder

OBJECTIVE

To examine the effects of stimulant medication on the sleep functioning of children with attention-deficit/hyperactivity disorder (ADHD) and identify predictors of sleep problems as a side effect of taking stimulant medication.

METHOD

One hundred sixty-three stimulant-naïve children (72% boys) aged 7 to 11 years diagnosed with ADHD (120 with ADHD predominantly inattentive type, 43 with ADHD combined type) participated in a 4-week, randomized, double-blind, placebo-controlled trial of once-daily (long-acting) methylphenidate (MPH). Parents completed weekly side-effect ratings including an item related to sleep problems.

RESULTS

Ten percent of patients had parent-rated sleep problems before the initiation of medication. Rates of parent-rated sleep problems during MPH titration generally increased with increasing MPH dose (placebo: 8%; low dose: 18%; medium dose: 15%; high dose: 25%). Differences emerged between children with (n = 16) or without (n = 147) preexisting sleep problems. Although 23% of children without preexisting sleep problems went on to have sleep problems at the highest MPH dose, only 37.5% of children with preexisting sleep problems still had sleep problems at the highest MPH dose. Lower weight and lower body mass index (BMI) were associated with increased sleep problems during MPH titration.

CONCLUSION

This study demonstrated a general association between increased MPH dose and increased sleep problems in children with ADHD, particularly for children of lower weight/BMI. However, a substantial proportion of children with preexisting sleep difficulties no longer had sleep problems on the highest MPH dose, which may help explain mixed findings reported to date in studies examining the impact of MPH on sleep functioning in children with ADHD and suggests that MPH dose titration should not be avoided solely on the basis of a child's premorbid sleep problems. Future research is needed to replicate and extend these findings to more specific domains of sleep functioning and to identify differences between children with persistent or improved sleep functioning as a result of MPH use.

ADHD-associated dopamine transporter, latrophilin and neurofibromin share a dopamine-related locomotor signature in Drosophila

Attention-deficit/hyperactivity disorder (ADHD) is a common, highly heritable neuropsychiatric disorder with hyperactivity as one of the hallmarks. Aberrant dopamine signaling is thought to be a major theme in ADHD, but how this relates to the vast majority of ADHD candidate genes is illusive. Here we report a Drosophila dopamine-related locomotor endophenotype that is shared by pan-neuronal knockdown of orthologs of the ADHD-associated genes Dopamine transporter (DAT1) and Latrophilin (LPHN3), and of a gene causing a monogenic disorder with frequent ADHD comorbidity: Neurofibromin (NF1). The locomotor signature was not found in control models and could be ameliorated by methylphenidate, validating its relevance to symptoms of the disorder. The Drosophila ADHD endophenotype can be further exploited in high throughput to characterize the growing number of candidate genes. It represents an equally useful outcome measure for testing chemical compounds to define novel treatment options.

No objectively measured sleep disturbances in children with attention-deficit/hyperactivity disorder

The main goal of this study was to gain more insight into sleep disturbances in children with attention-deficit/hyperactivity disorder, using objective measures of sleep quality and quantity. The evidence for sleep problems in children with attention-deficit/hyperactivity disorder thus far is inconsistent, which might be explained by confounding influences of comorbid internalizing and externalizing problems and low socio-economic status. We therefore investigated the mediating and moderating role of these factors in the association between attention-deficit/hyperactivity disorder and sleep problems. To control for the effects of stimulant medication use, all participants were tested free of medication. Sixty-three children with attention-deficit/hyperactivity disorder and 61 typically developing children, aged 6-13 years, participated. Sleep was monitored for one to three school nights using actigraphy. Parent and teacher questionnaires assessed symptoms of attention-deficit/hyperactivity disorder, internalizing behaviour, oppositional defiant disorder and conduct disorder. Results showed no differences between the attention-deficit/hyperactivity disorder and typically developing group in any sleep parameter. Within the attention-deficit/hyperactivity disorder group, severity of attention-deficit/hyperactivity disorder symptoms was not related to sleep quality or quantity. Moderation analyses in the attention-deficit/hyperactivity disorder group showed an interaction effect between attention-deficit/hyperactivity disorder symptoms and internalizing and externalizing behaviour on total sleep time, time in bed and average sleep bout duration. The results of our study suggest that having attention-deficit/hyperactivity disorder is not a risk factor for sleep problems. Internalizing and externalizing behaviour moderate the association between attention-deficit/hyperactivity disorder and sleep, indicating a complex interplay between psychiatric symptoms and sleep.