Melatonin has membrane receptor-independent hypnotic action on neurons: an hypothesis.

Melatonin, which is known to have sleep-promoting properties, has no morpho-physiological barriers and readily enters neurons and their subcellular compartments from both the blood and cerebrospinal fluid. It has multiple receptor-dependent and receptor-independent functions. Sleep is a neuronal function, and it can no longer be postulated that one or more anatomical structures fully control sleep. Neurons require sleep for metabolically driven restorative purposes, and as a result, the process of sleep is modulated by peripheral and central mechanisms. This is an important finding because it suggests that melatonin should have intracellular sleep-inducing properties. Based on recent evidence, it is proposed that melatonin induces sleep at the neuronal level independently of its membrane receptors. Thus, the hypnotic action of melatonin and the mechanisms involving the circadian rhythms are separate neurological functions. This is contrary to the presently accepted view.

The role of the thalamus in sleep, pineal melatonin production, and circadian rhythm sleep disorders.

The thalamus has a strong nonphotic influence on sleep, circadian rhythmicity, pineal melatonin production, and secretion. The opening of the sleep gate for nonrapid eye movement sleep is a thalamic function but it is assisted by melatonin which acts by promoting spindle formation. Thus, melatonin has a modulatory influence on sleep onset and maintenance. A remarkable similarity exists between spindle behavior, circadian rhythmicity, and pineal melatonin production throughout life. Together, the thalamic and chronobiological control of sleep leads to a new and improved understanding of the pathophysiology of circadian rhythm sleep disorders and also of the principles of sleep hygiene interventions.

Effectiveness outcomes in attention-deficit/hyperactivity disorder.

Attention-deficit/hyperactivity disorder (ADHD) is common, chronic, and associated with significant functional impairment. It is highly treatable. It is therefore not only a major public health problem but also one that provides a unique opportunity in medicine to make a significant difference. This article will discuss the methodology needed to demonstrate empirically the impact of treatment on actual burden of illness in practice. Where efficacy studies demonstrate whether a treatment can work, effectiveness studies tell us whether they actually do work. Clinical trials exclude incompetent, non-compliant, and seriously comorbid patients, so that the information obtained from these trials tells us the most about the patients we see the least. Small differences in effect size in pivotal trials of efficacy have become a key variable for rating treatments as first line or second line, without consideration of effectiveness variables such as comorbidity, difficulty with appetite or sleep, patient preference, capacity for compliance, timing of functional impairment, and substance use. These effectiveness variables are less well studied, but critical to clinical decision making. In reality, fewer than 10% of our patients comply with and persist with treatment. To learn more about why patients are discontinuing treatment, we need to explore measures of effectiveness empirically. Effectiveness studies are also important to provide regulatory bodies with the data they need to balance the risk of treatment with the risk of failing to treat. Practical clinical trials and naturalistic follow-up studies will allow us to evaluate the true clinical impact of short-term efficacy trials.

Sleep hygiene and melatonin treatment for children and adolescents with ADHD and initial insomnia.

OBJECTIVE: To evaluate the efficacy of sleep hygiene and melatonin treatment for initial insomnia in children with attention-deficit/hyperactivity disorder (ADHD). METHOD: Twenty-seven stimulant-treated children (6-14 years of age) with ADHD and initial insomnia (>60 minutes) received sleep hygiene intervention. Nonresponders were randomized to a 30-day double-blind, placebo-controlled, crossover trial of 5-mg pharmaceutical-grade melatonin provided by the study's sponsor. RESULTS: Sleep hygiene reduced initial insomnia to <60 minutes in 5 cases, with an overall effect size in the group as a whole of 0.67. Analysis of the trial data able to be evaluated showed a significant reduction in initial insomnia of 16 minutes with melatonin relative to placebo, with an effect size of 0.6. Adverse events were generally mild and not different from those recorded with placebo treatment. The effect size of the combined sleep hygiene and melatonin intervention from baseline to 90 days' posttrial was 1.7, with a mean decrease in initial insomnia of 60 minutes. Improved sleep had no demonstrable effect on ADHD symptoms. CONCLUSION: Combined sleep hygiene and melatonin was a safe and effective treatment for initial insomnia in children with ADHD taking stimulant medication.

Neurophysiology of circadian rhythm sleep disorders of children with neurodevelopmental disabilities.

This article reviews circadian rhythm sleep disorders (CRSDs) of children with neurodevelopmental disabilities. These sleep disturbances frequently occur in this population but they are misunderstood and under diagnosed. The causes and features of CRSD in children with brain disorders differ in many ways from those seen in typically developing children. It is the brain, including the eyes, which regulates sleep and circadian rhythmicity by modulating pineal melatonin production/secretion and when there is significant brain damage, the sleep/wake patterns may be modified. In most instances CRSD are not disorders of the suprachiasmatic nuclei because these small hypothalamic structures only adjust their functions to the changing photic and non-photic modulatory influences. Each form of CRSD is accompanied by characteristic changes in serum melatonin levels and clinical features. When nocturnal melatonin production/secretion is inappropriately timed or impaired in relation to the environment, timed melatonin replacement therapy will often be beneficial. In this review an attempt is made to clarify the neurophysiological mechanisms underlying the various forms of CRSD because without understanding the photic and non-photic influences on sleep, these sleep disorders can not be fully characterized, defined or even appropriately treated. In the future, the existing definitions for the different forms of CRSD should be modified by experts in pediatric sleep medicine in order to include children with neurodevelopmental disabilities.

Cerebral modulation of circadian sleep-wake rhythms.

The objective of this prospective observational study was to assess the association between dysrhythmia of EEG background (disturbance of cerebral connectivity) and sleep difficulties. Sixty children, aged 4 to 12 years, participated. Hospital records were reviewed, and sleep histories were obtained by interviewing the parents. EEGs of 39 subjects were normal, showed epileptiform activity, and/or mild to moderate background dysrhythmia. Severe unilateral dysrhythmia was noted in 6 and bilaterally in 15 EEGs, with all 15 children having profound neurodevelopmental disabilities and 14 of these 15 having long-standing severe chaotic sleep/wake patterns. Thus, there was a highly significant association between EEG evidence of severe bilateral dysrhythmia and chronic sleep/wake dysregulation. Unilateral dysrhythmia was not associated with sleep difficulties. This study delineates a specific sleep disorder in a group of children with marked neurodevelopmental disabilities and offers insight into how disturbed cerebral connectivity impacts the thalamocortical dynamics relating to neurodevelopmental disabilities, sleep, and melatonin production.

Long-term sleep disturbances in children: a cause of neuronal loss.

Short-term sleep loss is known to cause temporary difficulties in cognition, behaviour and health but the effects of persistent sleep deprivation on brain development have received little or no attention. Yet, severe sleep disorders that last for years are common in children especially when they have neurodevelopmental disabilities. There is increasing evidence that chronic sleep loss can lead to neuronal and cognitive loss in children although this is generally unrecognized by the medical profession and the public. Without the restorative functions of sleep due to total sleep deprivation, death is inevitable within a few weeks. Chronic sleep disturbances at any age deprive children of healthy environmental exposure which is a prerequisite for cognitive growth more so during critical developmental periods. Sleep loss adversely effects pineal melatonin production which causes disturbance of circadian physiology of cells, organs, neurochemicals, neuroprotective and other metabolic functions. Through various mechanisms sleep loss causes widespread deterioration of neuronal functions, memory and learning, gene expression, neurogenesis and numerous other changes which cause decline in cognition, behaviour and health. When these changes are long-standing, excessive cellular stress develops which may result in widespread neuronal loss. In this review, for the first time, recent research advances obtained from various fields of sleep medicine are integrated in order to show that untreated chronic sleep disorders may lead to impaired brain development, neuronal damage and permanent loss of developmental potentials. Further research is urgently needed because these findings have major implications for the treatment of sleep disorders.

Nutritional status of children with attention deficit hyperactivity disorder: a pilot study.

Objectives. This is a pilot study of the dietary intake and nutrient status of children with Attention Deficit Hyperactivity Disorder (ADHD). Method. Nutritional assessment of 43 children aged 6-12 with ADHD was performed using a 3-day food record, 24-hour recall, and serum assessors. Results. Macronutrient intake and consumption of Low-Nutrient Foods were comparable to population norms; however, 66% were found to be deficient in zinc and 23% in copper. Conclusions. This pilot study reports the food intake and nutrient status of children with ADHD and shows a predisposition for low zinc and copper status in ADHD.

Sleep Health Issues for Children with FASD: Clinical Considerations.

This article describes the combined clinical experience of a multidisciplinary group of professionals on the sleep disturbances of children with fetal alcohol spectrum disorders (FASD) focusing on sleep hygiene interventions. Such practical and comprehensive information is not available in the literature. Severe, persistent sleep difficulties are frequently associated with this condition but few health professionals are familiar with both FASD and sleep disorders. The sleep promotion techniques used for typical children are less suitable for children with FASD who need individually designed interventions. The types, causes, and adverse effects of sleep disorders, the modification of environment, scheduling and preparation for sleep, and sleep health for their caregivers are discussed. It is our hope that parents and also researchers, who are interested in the sleep disorders of children with FASD, will benefit from this presentation and that this discussion will stimulate much needed evidence-based research.

A randomized, placebo-controlled trial of controlled release melatonin treatment of delayed sleep phase syndrome and impaired sleep maintenance in children with neurodevelopmental disabilities.

The purpose of this study was to determine the efficacy of controlled-release (CR) melatonin in the treatment of delayed sleep phase syndrome and impaired sleep maintenance of children with neurodevelopmental disabilities including autistic spectrum disorders. A randomized double-blind, placebo-controlled crossover trial of CR melatonin (5 mg) followed by a 3-month open-label study was conducted during which the dose was gradually increased until the therapy showed optimal beneficial effects. Sleep characteristics were measured by caregiver who completed somnologs and wrist actigraphs. Clinician rating of severity of the sleep disorder and improvement from baseline, along with caregiver ratings of global functioning and family stress were also obtained. Fifty-one children (age range 2-18 years) who did not respond to sleep hygiene intervention were enrolled. Fifty patients completed the crossover trial and 47 completed the open-label phase. Recordings of total night-time sleep and sleep latency showed significant improvement of approximately 30 min. Similarly, significant improvement was observed in clinician and parent ratings. There was additional improvement in the open-label somnolog measures of sleep efficiency and the longest sleep episode in the open-label phase. Overall, the therapy improved the sleep of 47 children and was effective in reducing family stress. Children with neurodevelopmental disabilities, who had treatment resistant chronic delayed sleep phase syndrome and impaired sleep maintenance, showed improvement in melatonin therapy.

Sleep hygiene for children with neurodevelopmental disabilities.

Sleep disturbances in children with neurodevelopmental disabilities are common and have a profound effect on the quality of life of the child, as well as the entire family. Although interventions for sleep problems in these children often involve a combination of behavioral and pharmacologic strategies, the first line of treatment is the promotion of improved sleep habits or "hygiene." Despite the importance of sleep-hygiene principles, defined as basic optimal environmental, scheduling, sleep-practice, and physiologic sleep-promoting factors, clinicians often lack appropriate knowledge and skills to implement them. In addition, sleep-hygiene practices may need to be modified and adapted for this population of children and are often more challenging to implement compared with their healthy counterparts. This first comprehensive, multidisciplinary review of sleep hygiene for children with disabilities presents the rationale for incorporating these measures in their treatment, outlines both general and specific sleep-promotion practices, and discusses problem-solving strategies for implementing them in a variety of clinical practice settings.

Evidence supporting the use of melatonin in short gestation infants.

Pineal melatonin regulates circadian rhythms and influences sleep. Melatonin also has protective actions against tissue damage from free-radicals and other toxins. Evidence is presented that this indoleamine is involved in pre- and postnatal brain (and ocular) development and intrauterine growth. In the absence of maternal melatonin, short gestation infants have a prolonged period of melatonin deficiency. Melatonin supplementation, which has a benign safety profile, may help reduce complications in the neonatal period that are associated with short gestation. We believe that this treatment might result in a wide range of health benefits, improved quality of life and reduced healthcare costs.

Long-term effectiveness outcome of melatonin therapy in children with treatment-resistant circadian rhythm sleep disorders.

To date, there have been no prospective long-term studies of melatonin therapy in children. We report here data from a prospective follow-up study of 44 children with neurodevelopmental disabilities and treatment-resistant circadian rhythm sleep disorders (CRSD) who had participated in a placebo controlled, double blind cross-over trial of sustained-release melatonin. The follow-up study involved a structured telephone interview of caregivers every 3 months for upto 3.8 yr. The caregivers provided ratings of satisfaction, adverse effects, benefits, persistence with treatment and additional medications. Changes in melatonin dose were recorded. Open ended questions were included to capture caregivers' impressions and comments concerning melatonin therapy. Adverse reaction to melatonin therapy and development of tolerance were not evident. Better sleep was associated with reported improvement in health, behavior and learning. At the end of the study, the parental comments regarding the effectiveness of long-term melatonin therapy were highly positive. Parents whose children had sleep maintenance difficulties expressed a wish to have a commercially available controlled-release melatonin product which would promote sleep for 8-10 hr. Hypnotics for children with CRSD should be considered a second line of treatment for those who fail to respond to sleep hygiene and/or melatonin.