Reut Gruber

Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep1

Leaders from the Canadian Society for Exercise Physiology convened representatives of national organizations, content experts, methodologists, stakeholders, and end-users who followed rigorous and transparent guideline development procedures to create the Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep. These novel guidelines for children and youth aged 5-17 years respect the natural and intuitive integration of movement behaviours across the whole day (24-h period). The development process was guided by the Appraisal of Guidelines for Research Evaluation (AGREE) II instrument and systematic reviews of evidence informing the guidelines were assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Four systematic reviews (physical activity, sedentary behaviour, sleep, integrated behaviours) examining the relationships between and among movement behaviours and several health indicators were completed and interpreted by expert consensus. Complementary compositional analyses were performed using Canadian Health Measures Survey data to examine the relationships between movement behaviours and health indicators. A stakeholder survey was employed (n = 590) and 28 focus groups/stakeholder interviews (n = 104) were completed to gather feedback on draft guidelines. Following an introductory preamble, the guidelines provide evidence-informed recommendations for a healthy day (24 h), comprising a combination of sleep, sedentary behaviours, light-, moderate-, and vigorous-intensity physical activity. Proactive dissemination, promotion, implementation, and evaluation plans have been prepared in an effort to optimize uptake and activation of the new guidelines. Future research should consider the integrated relationships among movement behaviours, and similar integrated guidelines for other age groups should be developed.

Assessment and Management of Sleep Problems in Youths With Attention-Deficit/Hyperactivity Disorder

OBJECTIVE To provide evidence- or consensus-based recommendations concerning the assessment and management of sleep problems in youths with attention-deficit/hyperactivity disorder (ADHD). METHOD PubMed, Ovid, EMBASE, and Web of Knowledge were searched through October 31, 2012. When no evidence was available, consensus of the authors was achieved. The evidence-level of the recommendations on the management of sleep disturbances was based on the Scottish Intercollegiate Guidelines Network (SIGN) system. RESULTS A total of 139 original articles on sleep and childhood ADHD were retrieved, including 22 on treatment of sleep disturbances. This review focuses on behaviorally based insomnia, circadian rhythm disorder, sleep-disordered breathing, restless legs syndrome/periodic limb movement disorder, and sleep disturbances due to comorbid psychiatric disorders or ADHD medications. Healthy sleep practices are recommended as the foundation of management strategies. Behavioral interventions should be considered as first-line treatment of insomnia, although further evidence from randomized controlled trials (RCTs) is needed to prove their efficacy in ADHD. Among pharmacological treatments, RCTs support the use of melatonin to reduce sleep-onset delay, whereas there is more limited evidence for other medications. CONCLUSION Growing empirical evidence is informing assessment/management strategies of sleep problems in youths with ADHD. However, further RCTs are warranted to support current recommendations.

Impact of Sleep Extension and Restriction on Children’s Emotional Lability and Impulsivity

OBJECTIVE: To examine the impact of moderate sleep extension and restriction on child behavior in school. METHODS: We conducted a randomized parallel group study to determine the impact of an experimental sleep extension (addition of 1 hour of sleep relative to baseline habitual sleep duration on weekdays) and experimental sleep restriction (elimination of 1 hour of sleep relative to baseline habitual sleep duration on weekdays) on child behavior in school. The primary outcome measures were scores on the Conners’ Global Index Scale, as determined by teachers blinded to sleep status of the participants. A sample of 34 typically developing children aged 7 to 11 years with no reported sleep problems and no behavioral, medical, or academic issues participated in the study. RESULTS: Our main findings were that (1) a cumulative extension of sleep duration of 27.36 minutes was associated with detectable improvement in Conners’ Global Index–derived emotional lability and restless-impulsive behavior scores of children in school and a significant reduction in reported daytime sleepiness; and (2) a cumulative restriction of sleep of 54.04 minutes was associated with detectable deterioration on such measures. CONCLUSIONS: A modest extension in sleep duration was associated with significant improvement in alertness and emotional regulation, whereas a modest sleep restriction had opposite effects.

Short sleep duration is associated with poor performance on IQ measures in healthy school-age children

OBJECTIVE To examine the associations between habitual sleep duration and intellectual functioning in healthy, well-rested, school-age children. METHODS The study group consisted of 39 healthy children, aged 7-11 years old. Nightly actigraphic sleep recordings were taken for four consecutive nights to determine habitual week-night sleep duration in the home environment. Objective measures of cognitive functioning and sleepiness were used to measure daytime functioning. RESULTS Longer habitual sleep duration in healthy school-age participants was associated with better performance on measures of perceptual reasoning and overall IQ, as measured by the WISC-IV, and on reported measures of competence and academic performance. No association between sleep duration and the studied behavioral measures was found. CONCLUSIONS These findings support the hypothesis that sleep duration is differentially related to some components of cognitive functioning, even in the absence of evidence for sleep deprivation or attention deficits.

Systematic review of the relationships between sleep duration and health indicators in school-aged children and youth

The objective of this systematic review was to examine the relationships between objectively and subjectively measured sleep duration and various health indicators in children and youth aged 5-17 years. Online databases were searched in January 2015 with no date or study design limits. Included studies were peer-reviewed and met the a priori-determined population (apparently healthy children and youth aged 5-17 years), intervention/exposure/comparator (various sleep durations), and outcome (adiposity, emotional regulation, cognition/academic achievement, quality of life/well-being, harms/injuries, and cardiometabolic biomarkers) criteria. Because of high levels of heterogeneity across studies, narrative syntheses were employed. A total of 141 articles (110 unique samples), including 592 215 unique participants from 40 different countries, met inclusion criteria. Overall, longer sleep duration was associated with lower adiposity indicators, better emotional regulation, better academic achievement, and better quality of life/well-being. The evidence was mixed and/or limited for the association between sleep duration and cognition, harms/injuries, and cardiometabolic biomarkers. The quality of evidence ranged from very low to high across study designs and health indicators. In conclusion, we confirmed previous investigations showing that shorter sleep duration is associated with adverse physical and mental health outcomes. However, the available evidence relies heavily on cross-sectional studies using self-reported sleep. To better inform contemporary sleep recommendations, there is a need for sleep restriction/extension interventions that examine the changes in different outcome measures against various amounts of objectively measured sleep to have a better sense of dose-response relationships.

Future Research Directions in Sleep and ADHD Report of a Consensus Working Group

Objective: To explore relationships between basic and translational science research regarding sleep and ADHD in children. Method: A multidisciplinary group of experts in pediatric sleep medicine and ADHD convened in November 2010 to summarize the current literature, delineate knowledge gaps, and formulate recommendations regarding future research directions and priorities. Results: Six major research areas of interest were identified: (a) brain centers regulating sleep, arousal, and attention; (b) neurotransmitter systems involved in both sleep and attention regulation; (c) alterations of neural systems regulating sleep in ADHD; (d) phenotypic similarities between behavioral, mood, and cognitive manifestations of insufficient/disrupted sleep and ADHD; (e) hypoarousal and sleepiness in ADHD; and (f) external sleep–wake signals that affect sleep regulation in ADHD. Conclusion: An enhanced understanding of the complex mechanisms regulating sleep promotion, wakefulness, and attention may contribute to new insights regarding the core impairments in ADHD and lead to the development of new therapies.

Dose Effects and Comparative Effectiveness of Extended Release Dexmethylphenidate and Mixed Amphetamine Salts

OBJECTIVE To compare the dose effects of long-acting extended-release dexmethylphenidate (ER d-MPH) and ER mixed amphetamine salts (ER MAS) on attention-deficit/hyperactivity disorder (ADHD) symptom dimensions, global and specific impairments, and common adverse events associated with stimulants. METHODS Fifty-six children and adolescents with ADHD participated in an 8-week, double-blind, crossover study comparing ER d-MPH (10, 20, 25-30 mg) and ER MAS (10, 20, 25-30) with a week of randomized placebo within each drug period. Efficacy was assessed with the ADHD Rating Scale-IV (ADHD-RS-IV), whereas global and specific domains of impairment were assessed with the Clinical Global Impressions Severity and Improvement Scales and the parent-completed Weiss Functional Impairment Scale, respectively. Insomnia and decreased appetite, common stimulant-related adverse events, were measured with the parent-completed Stimulant Side Effects Rating Scale. RESULTS Both ER d-MPH and ER MAS were associated with significant reductions in ADHD symptoms. Improvement in Total ADHD and Hyperactivity/Impulsivity symptoms were strongly associated with increasing dose, whereas improvements in Inattentive symptoms were only moderately associated with dose. About 80% demonstrated reliable change on ADHD-RS-IV at the highest dose level of ER MAS compared with 79% when receiving ER d-MPH. Decreased appetite and insomnia were more common at higher dose levels for both stimulants. Approximately 43% of the responders were preferential responders to only one of the stimulant formulations. CONCLUSIONS Dose level, rather than stimulant class, was strongly related to medication response.

School-based sleep promotion programs: Effectiveness, feasibility and insights for future research

Adolescent sleep restriction is prevalent in todays society and is associated with major negative consequences for adolescent development and well-being. In the present review, we examine efforts to reduce adolescent sleep restriction via school-based sleep promotion programs. Such programs effectively enhance sleep knowledge but usually do not succeed in maintaining sleep behavioral changes. This may be because insufficient consideration is given to the importance of integrating motivational components into the programs. We suggest that future interventions should consider the use of individually tailored approaches to sleep promotion. We recommend the use of motivational interviewing, which can detect individual differences in the degree of willingness to change, thus allowing motivational barriers to be adequately addressed on an individual basis. Furthermore, we suggest that individually tailored sleep promotion strategies could be delivered to a significant proportion of adolescents via internet-based communication.

The Interplay Between Sleep and Emotion Regulation: Conceptual Framework Empirical Evidence and Future Directions

Emotions are biologically-based responses that help an organism meet challenges and opportunities, and involve changes in subjective experience, behavior, and physiology. Emotions arise when something important to us is at stake. Although many factors have been associated with healthy emotional regulation, the role of sleep in this process has been largely ignored. Recent studies, however, have begun to delineate how sleep critically affects emotional functioning. Nighttime sleep affects daytime mood, emotional reactivity and the capacity to regulate positive and negative emotions; conversely, daytime experiences affect sleep. Hence, there is a complex interplay between sleep and emotional regulation. The objective of this article is to examine this interplay in adults. This objective is addressed by utilizing a framework that identifies key aspects of the relationship between sleep and emotion. We propose that the connectivity between the emotional centers of the brain — the prefontal cortex and the amygdala — is in part dependent on the homeostatic sleep system such that connectivity between these brain networks is higher when rested and lower when sleep deprived. High connectivity drives more efficient executive functioning, while a disconnect leads to poor executive functioning capacity including emotional reactivity and impulsivity. The cognitive effects of the homeostatic system are couple with the mood regulation effects of the circadian system together dictating the degree to which one experiences emotional regulation or dysregulation. Further, the affective brain systems of individuals with clinical symptomology and/or pathology are suggested to be more vulnerable to homeostatic pressure and circadian lows or misalignment resulting in increased affective clinical symptomology. We review empirical evidence that supports this framework and explore the implications of this framework. Finally, we describe future directions for this type of work.

The association between sleep spindles and IQ in healthy school-age children

Recent studies have suggested that sleep is associated with IQ measures in children, but the underlying mechanism remains unknown. An association between sleep spindles and IQ has been found in adults, but only two previous studies have explored this topic in children. The goal of this study was to examine whether sleep spindle frequency, amplitude, duration and/or density were associated with performance on the perceptual reasoning, verbal comprehension, working memory, and processing speed subscales of the Wechsler Intelligence Scale for Children-IV (WISC-IV). We recruited 29 typically developing children 7-11 years of age. We used portable polysomnography to document sleep architecture in the natural home environment and evaluated IQ. We found that lower sleep spindle frequency was associated with better performance on the perceptual reasoning and working memory WISC-IV scales, but that sleep spindle amplitude, duration and density were not associated with performance on the IQ test.