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INTRODUCTION — Identification of sleep problems in children is important because a growing body of evidence suggests that sleep disorders may interfere with physical, cognitive, emotional, and social development. Conversely, children with neurodevelopmental problems, learning differences, or behavior problems may be at heightened risk for sleep problems compared with the general pediatric population [1-5].
Clinicians should incorporate questions about sleep into routine health assessment for children of all ages because parents may not volunteer information about their child's sleep, or may not appreciate the potential relationship between sleep problems and daytime behavior. Sleep problems present most commonly in the outpatient setting, but the hospitalized child may develop sleep problems during an acute illness, or chronic sleep disorders may come to medical attention during hospitalization.
Children with sleep disorders may present with different symptoms than adults. As an example, in contrast with adults, most children with obstructive sleep apnea (OSA) are not obese, and many children present with daytime attentional or behavioral problems rather than overt sleepiness [3,6]. Even within the pediatric age group, the clinical manifestations of sleep problems may vary by age and developmental level. For example, a school-aged child with excessive sleepiness may exhibit motor overactivity, inattentiveness, irritability, or oppositional behavior rather than overt sleepiness [7,8]. Sleep problems such as difficulty initiating or maintaining sleep (insomnia) may coexist with anxiety or depression in the adolescent, and may worsen certain medical or psychiatric problems.
This topic review will discuss the approach to taking a structured sleep history, provide an overview of specific sleep problems that may present during childhood, and explain indications for further diagnostic testing. Specific sleep disorders are discussed in more detail in other topic reviews:
APPROACH TO THE SLEEP HISTORY — A thorough sleep and medical history, guided by an understanding of normal sleep physiology, provides the foundation for diagnosis and management of sleep problems. A variety of checklists and questionnaires are available and may supplement the history. As an example, BEARS is a screening acronym that prompts a clinician to inquire about five sleep areas (B = Bedtime Issues, E = Excessive daytime sleepiness, A = Night awakenings, R = Regularity and duration of sleep, S = Sleep disordered breathing [or Snoring]) (table 1) . This type of screen can help identify patients who should be evaluated with a more detailed sleep history. There is no substitute for a thorough sleep and medical history by a knowledgeable clinician.
The sleep history is most contributory when it is structured, detailed, and systematic. The clinician should evaluate the sleep/wake schedule, difficulties initiating or maintaining sleep, abnormal movements or behavior during sleep, presence of snoring, and daytime accompaniments (eg, sleepiness, hyperactivity, inattentiveness, or irritability). Once the chief sleep complaint is identified, the history can focus on details that distinguish among disorders in that category (see 'Chief sleep complaint' below). The history should include details about the duration and frequency of the problem, temporal profile of onset (abrupt, gradual, intermittent), and degree of variability from night to night. The clinician should note what interventions or strategies have been tried and whether medications have been used.
Because parents are generally asleep during the night, they may struggle to provide a full history, as they may witness only portions of nighttime events. Some parents generate diaries or logs of sleep problems, and the widespread availability of home video cameras and smartphones have increased the opportunity for physicians to observe episodes of abnormal movement or behavior.
Completion of a sleep log during the two weeks prior to evaluation may provide important information regarding the sleep/wake pattern and nocturnal events (form 1). The log should include bed time, time of sleep onset, awakenings, rise time, nocturnal events, feeding pattern, naps, perceived quality of sleep, degree of alertness or sleepiness during the day, and observations regarding nocturnal events and medical or psychological stressors. The child's sleep patterns can then be compared with typical sleep patterns for his or her age group (figure 1), although it should be recognized that the average sleep time of children in a given age group varies by as much as two hours. (See "Sleep physiology in children", section on 'Maturation of sleep architecture'.)
CHIEF SLEEP COMPLAINT — The history begins with asking the parent or child to identity the chief complaint related to sleep. Despite the many ways children may experience sleep problems, most complaints can be distilled into one (or more) of four categories :
●Difficulty initiating or maintaining sleep
●Excessive daytime sleepiness
●Snoring or other breathing problems during sleep
●Abnormal movements or behaviors before or during sleep
The sleep history should always assess for difficulties in each of these areas. However, the main focus of the history depends on the nature of the chief complaint. The main diagnostic considerations in each of these categories are outlined below.
DIFFICULTY INITIATING OR MAINTAINING SLEEP — A useful way to gather history on a child with difficulty initiating sleep is to review the child's pattern of activity, hour by hour, from the point of arrival home from school or daycare until bedtime.
Behavioral contributors — Sleeplessness, or more specifically difficulty initiating or maintaining sleep (insomnia) often has behavioral roots, especially in young children. The problem can be clarified by evaluating the sleep schedule, sleeping environment, and bedtime routines. When problems are identified, the provider can advise the parent on how to modify the routine to improve sleep habits. (See "Behavioral sleep problems in children".)
●Pre-sleep activities — The clinician should record specific times of activities, including periods of exercise or competitive sports, homework times, dinner time, and whether and when the child routinely views television or plays electronic games. Use of electronic devices and social media appear to be important contributors to delayed sleep onset, whereas spending time with family may be protective . One study suggests that sedentary activity during the day is associated with increased sleep latency (ie, more difficulty falling asleep), whereas physical activity reduces sleep latency . The effects of sedentary activities or sports also depend on the timing of the activities, and vary between individual children.
●Bedtime routine — The clinician should discuss the bedtime routine, including the consistency with which parents adhere to schedules, how stalling is addressed, and where the child falls asleep. Patterns that are often associated with delayed sleep onset include:
•Stimulating activities are readily available in the sleep environment (such as television sets, laptop computers or tablets, cell phones, or video games in the bedroom).
•Presence of one or both parents as the child falls asleep.
•Siblings or other children in the bedroom, or other disruptive environmental circumstances (eg, a loud or unsafe neighborhood).
•Increased attention from the parents in response to a child's stalling behavior at bedtime, which inadvertently promotes the behavior. To avoid this, parents can establish a consistent response that extinguishes the unwanted behavior. (See "Behavioral sleep problems in children", section on 'Bedtime routines'.)
●Response to nighttime awakenings — When children experience nighttime awakenings, the parents' response can promote or extinguish the behavior. As an example, excessive parental attention in response to nighttime awakenings (including routinely allowing the child to switch beds) may perpetuate the problem. The clinician should assess whether the parents' response to nighttime awakenings is likely to reinforce the behavior, and should offer advice on how to reverse this pattern. For healthy toddlers and older infants, habitual nighttime feedings may disrupt sleep and are unnecessary. Clinicians should inquire about nighttime feedings and offer guidance on eliminating these when appropriate. (See "Behavioral sleep problems in children", section on 'Young children with behavioral insomnia'.)
Specific sleep disorders — Specific sleep disorders may be responsible for the insomnia in some cases and warrant specific treatment .
●Delayed sleep-wake phase disorder, which is a common cause of difficulty initiating sleep in adolescents and is characterized by a shift in sleep and wake time relative to the patient's desired or required sleep schedule. (See "Delayed sleep-wake phase disorder".)
●Restless legs syndrome, which usually can be distinguished by questioning about the urge to move the legs, which is the primary symptom of this movement disorder. (See "Restless legs syndrome/Willis-Ekbom disease and periodic limb movement disorder in children".)
●Nightmares, which may occur in any child but are more frequent in those with anxiety or post-traumatic stress disorder. (See "Sleepwalking and other parasomnias in children", section on 'Nightmare disorders'.)
Other contributors — The following problems contribute to insomnia in some children. In such cases, the insomnia is unlikely to respond to behavioral therapy alone until these issues are addressed.
●Psychosocial dysfunction — Psychosocial dysfunction may cause or present as a sleeping problem. Conversely, children's sleeping problems can contribute to household and marital stress. The clinician should probe the psychosocial history, including the presence of marital discord, use of alcohol or drugs by household members, and any indications of child abuse. In some cases, it may be necessary to interview the child alone to get a reliable history.
●Anxiety or depression — Anxiety (including separation anxiety) and depression are common causes of insomnia in children. All children have fears at some point in their lives, and these may interfere with sleep. If the fears are persistent and consistently interfere with functioning (ie, sleep), evaluation for a specific phobia or generalized anxiety disorder may be warranted (see "Overview of fears and phobias in children and adolescents"). The prevalence of depression is about 2 percent among school-aged children and rises sharply during adolescence. In addition to insomnia, symptoms include depressed or irritable mood, diminished interest or pleasure (anhedonia), change in appetite or weight status, psychomotor agitation or retardation (eg, talking or moving more slowly than is usual for them), fatigue or loss of energy, feelings of worthlessness or guilt, impaired concentration, or recurrent thoughts of death or suicide. (See "Pediatric unipolar depression: Epidemiology, clinical features, assessment, and diagnosis".)
●Concomitant medical problems — The clinician should identify chronic medical problems that may influence sleep, including chronic or recurrent pain, symptoms suggestive of gastroesophageal reflux, breathing problems during wakefulness or sleep, and the medication history. Such medical problems may disrupt sleep because of discomfort or because of medical interventions (eg, medications, breathing treatments, or feedings) that are given during the night. Some medications, including stimulants used for attention deficit-hyperactivity disorder (ADHD), may affect sleep latency and continuity. (See 'Concomitant medical problems' below and 'Medications, caffeine, and alcohol' below.)
EXCESSIVE DAYTIME SLEEPINESS — For evaluation of the child with excessive daytime sleepiness, the history is directed at identification of potential causes. If parents are not aware of age-appropriate norms for nighttime sleep and daytime napping, they may fail to recognize poor sleep hygiene or chronic sleepiness in their child. Furthermore, a child with insufficient sleep may not appear sleepy to parents or clinicians. Instead, the child may exhibit attentional difficulties due to unsuspected sleepiness, hyperactivity secondary to efforts to stay awake, or aggressive and disruptive behavior that reflects inability of a sleep-deprived frontal cortex to regulate emotion normally. (See "Cognitive and behavioral consequences of sleep disorders in children".)
Excessive sleepiness is of particular concern in older adolescents because of the known association between drowsy driving and accidents. Driving while drowsy can have the same consequences as driving while under the influence of drugs or alcohol including reduced attentiveness, delayed reaction times, and impaired decision-making. Young men between 16 and 24 years of age are most at risk for having an accident while driving drowsy . The American Academy of Sleep Medicine (AASM) has advocated for policies and procedures that will reduce drowsy driving such as inclusion of material on drowsy driving in state drivers' education manuals and curricula, and on drivers' licensing examinations and other initiatives. Physicians involved with evaluation and management of older adolescents who drive should incorporate appropriate education and recommendations about drowsy driving into their management plan. (See "Drowsy driving: Risks, evaluation, and management", section on 'High-risk populations'.)
Sleepiness should be differentiated from chronic fatigue, which often involves somatic complaints, such as weakness or easy fatigability, malaise, nonrestorative sleep patterns, and depression or other emotional disturbances. (See "Fibromyalgia in children and adolescents: Clinical manifestations and diagnosis".)
Insufficient sleep — Insufficient sleep is the leading cause of daytime sleepiness in children and teenagers . The sleep requirement for children and teenagers is age-dependent and can show a rather wide range, especially in infants. For optimal health, daytime functioning and development, the following sleep times are recommended on a regular basis [16,17]. These consensus recommendations were made by the AASM and endorsed by the American Academy of Pediatrics (AAP), and are very similar to those of the National Sleep Foundation (figure 1). Of note, these consensus recommendations derive largely from studies that collected parent reports, rather than objective measures:
●Infants 4 to 12 months – 12 to 16 hours (including naps)
●Toddlers 1 to 2 years – 11 to 14 hours (including naps)
●3 to 5 year old children – 10 to 13 hours (including naps)
●6 to 12 year old children – 9 to 12 hours
●Teens 13 to 18 years – 8 to 10 hours
AASM did not make specific recommendations for newborns 0 to 3 months of age because of the wide range of variation in sleep duration and patterns; infants in this age group generally sleep 14 to 17 hours daily (including naps). Insufficient sleep is often a consequence of poor sleep hygiene (which contributes to insufficient sleep time), failure of the parents or older children to prioritize sleep, and/or medication side effects. Strategies to improve sleep habits in children are outlined in the table (table 2) and discussed in more detail in a separate topic review. (See "Behavioral sleep problems in children".)
Delayed sleep-wake phase disorder — Delayed sleep-wake phase disorder involves a circadian rhythm disturbance characterized by a shift in sleep and wake time relative to the patient's desired or required sleep schedule. It is particularly common among adolescents and young adults, and results in complaints of difficulty waking in the morning and difficulty initiating sleep at the targeted time. (See "Delayed sleep-wake phase disorder".)
Narcolepsy — Children with narcolepsy often experience severe sleepiness, including falling asleep during meal times and conversation, sports events, or social activities. The disorder is most often diagnosed during adolescence, but is increasingly recognized in younger children. Academic failure is common. Unique features that may or may not be present initially are cataplexy (sudden bilateral loss of tone, often precipitated by a sudden emotion such as laughter), sleep paralysis, or hypnagogic hallucinations (vivid, dreamlike imagery at sleep onset) [8,18-21]. Cataplexy should be differentiated from atonic seizures, syncope, vestibular disorders, transient ischemic attacks, and behaviorally based loss of postural tone. The diagnostic evaluation for narcolepsy includes a focused history and physical examination, polysomnography (PSG), and multiple sleep latency test (MSLT) (see 'Multiple sleep latency test' below). Narcolepsy is discussed in detail separately. (See "Narcolepsy in children" and "Clinical features and diagnosis of narcolepsy in adults".)
Other central disorders of hypersomnolence include Kleine-Levin syndrome (recurrent hypersomnia, which may be menstrual-related), and idiopathic hypersomnia [22-24]. (See "Classification of sleep disorders", section on 'Central disorders of hypersomnolence'.)
Other causes — The following disorders sometimes present with daytime sleepiness as a chief complaint, but usually can be distinguished by their other clinical features:
●Obstructive sleep apnea – Obstructive sleep apnea (OSA) is also a common cause for daytime sleepiness or associated behavioral problems. The sleepiness is often less obvious in children compared with adults with OSA. Complaints of excessive snoring or abnormal breathing during sleep are usually, but not always, present. (See 'Obstructive sleep apnea' below.)
●Periodic limb movement disorder – Periodic limb movement disorder (PLMD) is characterized by periodic episodes of repetitive limb movements during sleep. It may present with daytime sleepiness. Periodic limb movements and arousals that occur with them can also be associated with transient increases in blood pressure. Affected children also may complain of symptoms of restless legs syndrome (RLS), which is a closely associated disorder. (See 'Periodic or rhythmic movements' below.)
●Underlying medical conditions – Many medical conditions may be associated with excessive daytime sleepiness, diminished alertness, fatigue, or related complaints that can be challenging to distinguish. Such conditions include:
•Any chronic disease – eg, including anemia, cardiac disease, malignancy, or metabolic problems
•Acquired central nervous system (CNS) disorders
-After traumatic brain injury (concussion) or in association with meningitis, encephalitis, or certain toxic exposures (eg, carbon monoxide and heavy metals).
-Increased intracranial pressure, due to hydrocephalus or mass lesions in the region of the third ventricle or posterior hypothalamus . Headaches, diplopia, or papilledema may be present. Further evaluation with neuroimaging is indicated for children with suspected mass lesions. (See "Elevated intracranial pressure (ICP) in children: Clinical manifestations and diagnosis".)
SNORING OR BREATHING PROBLEMS
Obstructive sleep apnea — Obstructive sleep apnea (OSA) is particularly common in school-aged children with adenotonsillar hypertrophy, or in children of any age with obesity. It typically presents with complaints of snoring or other sounds, such as snorting or gasping. It is often associated with neurobehavioral symptoms such as inattention, hyperactivity, impulsivity, and irritability. Excessive daytime sleepiness is less obvious than in adults with OSA, but may be evident on specific questioning. Children whose initial screening reveals any of these symptoms, or those with marked adenotonsillar hypertrophy or obesity, warrant a more detailed clinical evaluation. The detailed evaluation typically is performed by a sleep medicine specialist or otolaryngologist, and usually includes polysomnography (PSG) . Alternatively, the referring provider may be able to arrange for a PSG if a facility with experience in pediatric PSG is available. (See 'Polysomnography' below and "Evaluation of suspected obstructive sleep apnea in children" and "Cognitive and behavioral consequences of sleep disorders in children", section on 'Sleep-related breathing disorders'.)
Snoring may occur more frequently in the supine position. When the airway obstruction is severe, the snoring often occurs in any sleeping position. However, in contrast with adults with OSA, children with OSA may not snore, and they may not experience recurrent awakenings or arousals with episodes of obstruction. Episodes of snoring, gasping, apnea, and sudden arousal during airway obstruction are often observed more frequently in the final one-third of the night because upper airway obstruction is often worse during rapid eye movement (REM) sleep . (See "Sleep physiology in children", section on 'Association of sleep disorders with sleep states'.)
Other nighttime symptoms of OSA may include paradoxical chest-abdominal movements, retractions, observed apneas, restless sleep, excessive sweating, or cyanosis. Nocturnal enuresis occurs more frequently in children with OSA than in children without OSA, and enuresis may improve in association with treatment of OSA [26,27]. Daytime symptoms may include nasal obstruction, mouth breathing or other signs of adenotonsillar hypertrophy (eg, "adenoid facies" (picture 1)), poor attentiveness, irritability or other behavior problems, or daytime sleepiness.
Children with severe OSA may sleep in the upright or semi-upright position to maintain upper airway patency. Severe forms may be associated with failure to thrive, cor pulmonale, or delayed development . Upon questioning, parents may acknowledge staying awake during the night to monitor whether their child was breathing, and to stimulate the child to make him or her breathe during sleep [21,28].
MOVEMENTS OR BEHAVIORS DURING SLEEP — Abnormal movements or behaviors may be observed in a variety of sleep disorders, including respiratory disturbance, parasomnias, and sleep-related epilepsy (nocturnal seizures) (table 3). Nocturnal events associated with high amplitude movements may present a risk of injury to the child, and protective measures may be required.
A thorough history is adequate in most cases for characterization of nocturnal events and establishing a diagnosis. Recordings of representative clinical events with a home video camera or smartphone may provide useful information. In some cases, additional diagnostic evaluation, such as electroencephalography (EEG) or prolonged EEG/video monitoring is necessary.
●Sleep starts (hypnic jerks) – Sleep starts are abrupt, startle-like movements that occur as one is drifting off to sleep. They are very common in all age groups. (See "Sleep-related movement disorders in childhood", section on 'Sleep starts (hypnic jerks)'.)
●Limb jerks associated with OSA – Limb movements may occur during arousals triggered by obstructive sleep apnea (OSA), but these are not stereotyped; they are not scored as periodic limb movements. OSA usually can be distinguished by snoring, paradoxical abdominal movements, and/or risk factors such as adenotonsillar hypertrophy or obesity, and the diagnosis is confirmed by polysomnography (PSG). (See 'Obstructive sleep apnea' above.)
●Benign sleep myoclonus of infancy – This is characterized by brief myoclonic jerks of the limbs or the trunk during sleep in infants younger than six months of age; the condition is uncommon and benign. (See "Sleep-related movement disorders in childhood", section on 'Benign sleep myoclonus of infancy'.)
Periodic or rhythmic movements — Periodic or rhythmic movements during sleep are common in children and include (table 5):
●Rhythmic movement disorder – Rhythmic movements of the head, neck, or trunk associated with sleep are likely developmental (physiologic) in infants and young children. They are most common in infants and toddlers, and often resolve spontaneously by five years of age. The term rhythmic movement disorder is used if the movements have or are likely to have significant consequences such as self-injury or interference with normal sleep .
Typical manifestations are body rocking, head rolling (side to side), or head banging, sometimes accompanied by rhythmic humming or inarticulate chanting. The movements often begin immediately prior to sleep onset and are sustained into light sleep . The distinctive character of rhythmic movements allows a clinical diagnosis in most cases, although in a few cases with atypical features, further investigation may be required to distinguish these from sleep-related epilepsy. (See "Sleep-related movement disorders in childhood", section on 'Rhythmic movement disorder'.)
●Periodic limb movement disorder (PLMD) – PLMD (nocturnal myoclonus) is characterized by periodic episodes of repetitive and highly stereotypic limb movements during sleep, as documented on PSG, and associated with sleep disturbance or daytime dysfunction . The movements usually involve extension of the great toe and partial flexion of the ankle, knee, and sometimes hip. When these movements are associated with repetitive partial arousals or awakenings, sleep is fragmented. In addition to the movements, affected children have daytime problems, often including diminished attentiveness .
There is significant overlap between PLMD and restless leg syndrome (RLS) in both children and adults. RLS is characterized by an urge to move the legs, usually accompanied by uncomfortable or unpleasant sensations in the legs. The symptoms begin or worsen during rest or inactivity, are relieved by movement, and occur exclusively or predominantly in the evening or night. Children with RLS or PLMD often have depressed serum ferritin levels, indicating reduced iron stores, and in this case the disorder may improve with iron supplementation. (See "Restless legs syndrome/Willis-Ekbom disease and periodic limb movement disorder in children".)
●Hypnagogic foot tremor – Hypnagogic foot tremor is a rhythmic movement of the feet or toes, occurring around the time of sleep onset with a periodicity of once every one to two seconds. It is a benign entity seen in both children and adults. The periodicity and timing near sleep onset distinguish it from periodic limb movements of sleep (table 5). (See "Sleep-related movement disorders in childhood", section on 'Hypnagogic foot tremor and alternating leg muscle activation'.)
Complex movements or behaviors — Complex movements during sleep usually are parasomnias, and are common in young children. Occasionally, sleep-related epilepsy can present with similar clinical features.
●Parasomnias – Parasomnias are episodic and complex behaviors that intrude into sleep. The most common parasomnias in children are sleepwalking, confusional arousals, and sleep terrors, which occur upon partial arousal from non-rapid eye movement (NREM) sleep . They are benign and most common in young children but occasionally occur in older children or adolescents. Common triggers include sleep deprivation and other sleep disorders, such as OSA.
Parasomnias usually are easily identified by a description or video record of the behavior and its timing. Rarely, certain types of sleep-related epilepsy can mimic parasomnias, but usually can be distinguished by clinical characteristics, or with nocturnal EEG if needed. Assessment includes gathering clinical history on common triggers such as insufficient sleep, or symptoms of OSA or RLS. (See "Sleepwalking and other parasomnias in children".)
●Sleep-related epilepsy – Sleep-related epilepsy (nocturnal seizures) may be generalized or focal (also known as partial or localization-related epilepsy). A generalized tonic clonic seizure arising out of sleep is usually obvious by history and not easy to confuse with a sleep disorder; the seizure involves bilateral tonic clonic movements, often with tongue biting or urinary incontinence, postictal drowsiness and confusion. It may be difficult for parents to provide a full description of nocturnal seizures since they may directly observe only the latter portion of the event rather than the beginning of the event. Assessment may include PSG with expanded EEG montage.
Benign (childhood) epilepsy with centrotemporal spikes (BECTS), also known as benign rolandic epilepsy, is one of the more common epilepsy syndromes in childhood. It is an age-dependent focal epilepsy of unknown etiology with a peak incidence in children between seven and nine years of age. The characteristic focal seizure type involves initial hemifacial clonic twitching accompanied by hypersalivation, evolving to a focal hemi-tonic-clonic seizure. The seizure tends to occur during nocturnal sleep, often in the early morning hours. (See "Sleep-related epilepsy syndromes", section on 'Benign focal epilepsies of childhood'.)
Juvenile myoclonic epilepsy typically occurs in otherwise healthy adolescents and is characterized by the triad of myoclonic jerks, generalized tonic-clonic seizures (GTCS), and absence seizures (also called petit mal). The seizures characteristically occur upon awakening, often in the early morning, or in association with sleep deprivation. By contrast, periodic limb movements occur during sleep, and are more likely in the first half of the night. (See "Juvenile myoclonic epilepsy".)
Temporal and frontal lobe seizures are relatively rare but distinctive focal epilepsies in sleep. Events are highly stereotypic (ie, the same behavior pattern recurs) and are often brief but clustered or frequent during the night. Occasionally these types of seizures may be difficult to distinguish from arousal (NREM) parasomnias (sleep walking, sleep terrors, and confusional arousals) because both may be associated with altered behavior, responsiveness, and automatisms, and because attempts to awaken a child during a parasomnia may precipitate a lengthy period of confusion (ie, partial arousal) that is reminiscent of a postictal state .
A key feature that differentiates temporal and frontal lobe seizures from parasomnias is the time of occurrence in the sleep period, as outlined in the table (table 6). NREM parasomnias typically occur in association with deeper stages of NREM sleep in the first one-third of the night . REM sleep phenomena (eg, nightmares, sleep paralysis, and REM sleep behavior disorder) tend to occur in the final one-third of the night, when REM sleep predominates [31,32]. Nocturnal seizures may occur during any stage of sleep but are observed most frequently in the transition into non-REM sleep, or upon arousal from sleep .
Details of NREM parasomnias and sleep-related epilepsy syndromes, and clinical approaches to distinguishing between these disorders, are discussed in separate topic reviews:
ADDITIONAL MEDICAL HISTORY
Concomitant medical problems — Evaluation of the child with sleep problems should also include a thorough review of the medical history, with a focus on possible neurodevelopmental or medical problems that may be associated with sleep disorders. These include:
●Chronic conditions that may disrupt sleep, such as reactive airways disease, gastroesophageal reflux, congenital heart disease, arthritis, and other causes of chronic pain. (See "Medical disorders resulting in problem sleeplessness in children".)
●Disorders associated with altered craniofacial anatomy or reduced oropharyngeal function, which predispose to obstructive sleep apnea (OSA). (See "Evaluation of suspected obstructive sleep apnea in children", section on 'Other'.)
●Neurological disorders such as cerebral palsy, intellectual disability, autism spectrum disorder and related disorders, and blindness, which are associated with neurobehavioral and circadian sleep disruption .
●Attention deficit hyperactivity disorder (ADHD), in which the association with sleep disorders is probably bidirectional:
•ADHD-associated behavioral problems and stimulant medications tend to cause sleep disruption. (See "Medical disorders resulting in problem sleeplessness in children", section on 'Attention deficit hyperactivity disorder'.)
•Conversely, some types of sleep disorders, such as OSA and restless legs syndrome (RLS), may cause behavioral symptoms that meet diagnostic criteria for ADHD, including inattention, hyperactivity, impulsivity, and irritability. In many cases, the behavioral symptoms improve or resolve if the sleep disorder is effectively treated. (See "Cognitive and behavioral consequences of sleep disorders in children".)
Medications, caffeine, and alcohol — A wide variety of medications can cause sleep disruption (table 7). Medications with adverse effects on sleep that are commonly encountered in pediatrics include:
●Stimulant medications (eg, for ADHD). (See "Pharmacology of drugs used to treat attention deficit hyperactivity disorder in children and adolescents", section on 'Stimulant adverse effects'.)
●Sedating medications – Medications with sedating effects include certain antihistamines, antidepressants (especially the tricyclic compounds), benzodiazepines, and antiseizure medications (especially barbiturates and topiramate), and alpha-adrenergic agonists (eg, clonidine) [35,36].
●Selective serotonin reuptake inhibitors (SSRIs) – SSRIs may increase awakenings, and abrupt withdrawal may worsen insomnia.
●Other substances – Caffeine-containing beverages (eg, colas, coffee, and tea) tend to delay sleep onset and cause insomnia. Alcohol tends to shorten latency to sleep but also may cause insomnia later in the night.
PHYSICAL EXAMINATION — The physical examination is directed towards identification of causes of sleep disorders, or sequelae associated with sleep pathology.
●General physical examination:
•General observations include the child's level of alertness (including possible fluctuations in degree of alertness) during the examination. Repetitive yawning, droopy eyelids, blank facial expression, frequent changes in position, overactivity, and irritability may indicate excessive sleepiness.
•Evaluation of growth parameters – Excessive weight gain and obesity are associated with an increased risk for obstructive sleep apnea (OSA). Failure to thrive also may be a consequence of OSA, or of an underlying chronic medical disorder. (See "Evaluation of suspected obstructive sleep apnea in children", section on 'Examination'.)
•Dysmorphic features such as those associated with Down syndrome or Prader-Willi syndrome, both of which are associated with OSA. (See "Down syndrome: Clinical features and diagnosis" and "Clinical features, diagnosis, and treatment of Prader-Willi syndrome".)
•Craniofacial anomalies, such as macrocephaly, microcephaly, micrognathia, or Pierre Robin syndrome, which are also associated with OSA. (See "Syndromes with craniofacial abnormalities".)
•Persistent mouth breathing or noisy breathing may suggest nasal obstruction.
•Clubbing, cyanosis, or edema may suggest heart failure. Lung examination may suggest chronic lung disease or reactive airways disease.
•Tonsillar or adenoidal hypertrophy, abnormally small upper airway, mandibular hypoplasia, micrognathia, retrognathia, high-arched hard palate, dependent soft palate, overjet, overbite, adenoidal facies (elongated face, mouth breathing); each of these features is associated with OSA. (See "Evaluation of suspected obstructive sleep apnea in children", section on 'Examination'.)
•Absent gag reflex, poor movement of the soft palate, or swallowing problems suggest bulbar dysfunction, which is associated with OSA.
•Signs of neuromuscular disease, including scoliosis and weakness. Children with neuromuscular disease are at risk for both OSA (due to oropharyngeal dysfunction) and sleep-related hypoventilation (due to respiratory muscle weakness). (See "Etiology and evaluation of the child with weakness".)
•Developmental milestones and cognitive function.
INDICATIONS FOR TESTING AND REFERRAL — Thorough assessment and treatment of children with sleep disorders can require a multidisciplinary approach and can involve clinicians in general pediatrics or family medicine as well as subspecialists in child neurology, psychiatry, psychology, otolaryngology, pulmonary medicine, and development. Board-certified sleep medicine physicians are generally trained to address sleep disorders in patients of all ages. After training, many though not all sleep medicine specialists continue to include children in their practices. Pediatricians who are fellowship-trained and board-certified in sleep medicine are not plentiful but often are available at academic centers or other large practices.
●Suspected obstructive sleep apnea (OSA) – If the child has persistent snoring and other risk factors or symptoms of OSA, consideration should be given to a referral to an otolaryngologist (ear, nose, and throat specialist) or sleep physician for further evaluation. Existing literature does not indicate which referral serves best, and local resources and access to care may vary. If polysomnography (PSG) is indicated, this can be arranged by the sleep physician. Alternatively, the referring provider may be able to arrange directly for a PSG if a facility with experience in pediatric PSG is available; children with abnormal results of PSG or other significant sleep problems can then be referred to the appropriate specialist.
●Difficulty initiating and maintaining sleep (insomnia) – In some cases, the primary care clinician may provide counseling to improve sleep hygiene. For children with suspected emotional triggers, further evaluation and referral to a mental health specialist is appropriate. If this is not successful, then referral to a specialist in sleep medicine may be helpful, especially for children with neurological or developmental disorders. (See "Behavioral sleep problems in children".)
●Suspected movement disorder – If the child has a suspected sleep-related movement disorder such as restless legs syndrome (RLS) or periodic limb movement disorder (PLMD) that disrupts sleep or quality of life, referral to a sleep physician may be helpful to confirm the diagnosis and initiate treatment. Alternatively, the clinician may choose to recommend avoidance of caffeine and to evaluate for deficiency of iron or ferritin before referring to a specialist. (See "Restless legs syndrome/Willis-Ekbom disease and periodic limb movement disorder in children".)
●Suspected nocturnal seizures – For children with an apparent parasomnia or sleep-related movement disorder with atypical features (eg, age of onset), the possibility of nocturnal seizures should be considered. Such patients should ideally be referred to a specialist in pediatric sleep medicine or a pediatric neurologist, if available. Patients with features strongly suggesting nocturnal seizures (eg, generalized tonic-clonic movements, or presence of daytime seizures), should be evaluated by a specialist in either pediatric neurology and/or pediatric sleep medicine.
●Suspected narcolepsy – Children with symptoms suggesting narcolepsy (eg, severe daytime sleepiness, with or without cataplexy, sleep paralysis, or hypnagogic hallucinations) should be referred to a sleep medicine physician for further evaluation. (See 'Multiple sleep latency test' below and "Narcolepsy in children".)
Children with typical parasomnias or sleep-related movements that are benign (eg, rhythmic movements in a toddler) sometimes can be addressed by a primary care provider who is familiar with diagnosis and management of these common conditions. Management also includes follow-up to ensure that the parasomnia resolves or remains consistent with a benign condition.
Polysomnography — Polysomnography (PSG) typically consists of an all-night recording performed in the sleep laboratory in order to characterize sleep architecture and sleep pathology. A number of physiological parameters are measured, including sleep stages (characterized using a combination of electroencephalography [EEG], eye movements, and muscle tone), respiratory function (including air flow at the nose and mouth, respiratory movements of the chest and abdomen, and oximetry), electrocardiogram (EKG), limb movements, a microphone to detect sounds such as snoring or vocalizations, and video recording to characterize movements or behaviors during sleep. A standardized scoring manual provides guidelines and criteria for analysis of PSG in adults and children . Specific criteria are also available for infants. (See "Overview of polysomnography in infants and children".)
Indications for laboratory-based PSG performed by a sleep technologist include [38,39]:
●Assessment for a sleep-related breathing disorder (eg, obstructive sleep apnea [OSA])
●Assessment for narcolepsy (in conjunction with a multiple sleep latency test [MSLT]) (see 'Multiple sleep latency test' below)
●Assessment for periodic limb movement disorder (PLMD) (see "Restless legs syndrome/Willis-Ekbom disease and periodic limb movement disorder in children")
●Titration of continuous positive airway pressure (CPAP) (see "CPAP for pediatric obstructive sleep apnea")
PSG also may be indicated for evaluation of :
●Patients with neuromuscular disorders and sleep-related symptoms.
●A parasomnia associated with clinical suspicion for a sleep-related breathing disorder or PLMD.
●Restless legs syndrome (RLS) usually can be diagnosed by clinical symptoms and is not an indication for PSG. However, PSG may be helpful in selected children with suspected RLS who require supportive data for the diagnosis.
PSG with an expanded electroencephalography (EEG montage; typically 16-channels) may be indicated for evaluation of :
●Patients with suspected sleep-related epilepsy when the initial clinical evaluation and standard EEG are inconclusive, to help distinguish the disorder from a parasomnia
●Patients with an atypical or potentially injurious parasomnia, to confirm the diagnosis and assess for sleep-related epilepsy
PSG is not routinely indicated for evaluation of difficulty initiating or maintaining sleep (insomnia), circadian rhythm disorders, uncomplicated parasomnias, chronic lung disease, depression, RLS, bruxism, or behaviorally-based sleep problems [38,40].
Multiple sleep latency test — The multiple sleep latency test (MSLT) is an objective, in-laboratory assessment for excessive daytime sleepiness . It is performed following nocturnal PSG and consists of five 20-minute nap opportunities at two-hour intervals across the day. The test is based on the concept that the speed with which one falls asleep is an indication of the severity of sleepiness. The MSLT is also used more specifically to assess for narcolepsy when the clinical history suggests this diagnosis .
During the MSLT, a sleep latency time of less than five minutes is markedly abnormal and supports a diagnosis of narcolepsy or severe sleep deprivation; affected individuals also tend to enter rapid eye movement (REM) sleep quickly. The International Classification of Sleep Disorders, 3rd edition (ICSD-3), requires a mean sleep latency of less than eight minutes and two or more sleep onset REM periods as part of the diagnostic criteria for narcolepsy . In prepubertal children, data suggest that mean sleep latency values of 8 to 15 minutes (rather than less than eight minutes) on the MSLT may be suggestive of pathological sleepiness . Abnormal entry into REM sleep may occur in disorders other than narcolepsy that are associated with fragmented nocturnal sleep, such as OSA, sleep deprivation, and as a rebound phenomenon after REM-suppressing medications are stopped abruptly. (See "Quantifying sleepiness", section on 'Multiple sleep latency test (MSLT)' and "Narcolepsy in children".)
Actigraphy — Actigraphy involves use of a wristwatch-like device to monitor movement at night , usually during a 5- to 14-day period. Actigraphy has been validated against PSG and shown to provide a reasonable estimate for patterns of sleep versus wakefulness in children and adults. The advantage of actigraphy over polysomnography is that it captures multiple days of data from the home environment. Actigraphy is typically used by sleep medicine specialists as part of a comprehensive characterization of sleep/wake patterns and to monitor response to interventions. (See "Overview of actigraphy".)
RESOURCES — The International Classification of Sleep Disorders, 3rd edition (ICSD-3), provides a diagnostic and coding manual for recognized sleep disorders . The classification provides a systematic review of the essential features, diagnostic criteria, prevalence, predisposing factors, pathology, complications, and polysomnographic findings associated with each recognized sleep disorder. The ICSD-3 includes separate entries for pediatric sleep disorders where children and adults differ most in presentation, diagnosis, evaluation, or treatment. The classification scheme is summarized in a separate topic review (see "Classification of sleep disorders").
The American Academy of Sleep Medicine (AASM) and Sleep Research Society (SRS) are active professional organizations dedicated to the advancement of sleep medicine and related research. The AASM websites (www.aasmnet.org and www.sleepeducation.org) and the SRS website (www.sleepresearchsociety.org) provide information on professional standards, education and training, accreditation, publications, research opportunities, and patient resources.
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Insomnia in children" and "Society guideline links: Sleep-related breathing disorders including obstructive sleep apnea in children".)
INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Basics topics (see "Patient education: Daytime sleepiness (The Basics)" and "Patient education: Night terrors, confusional arousals, and nightmares in children (The Basics)" and "Patient education: Sleepwalking in children (The Basics)")
SUMMARY AND RECOMMENDATIONS — Sleep disorders in children are very common and can impair academic function and daytime behavior. Clinicians should incorporate questions about sleep into their routine health assessment of children.
●A structured sleep history assesses the sleep/wake schedule, difficulties initiating or maintaining sleep, presence of snoring, abnormal movements or behavior during sleep, and daytime accompaniments (eg, sleepiness, inattentiveness, or irritability). The history should include details about the duration and frequency of the problem, temporal profile of onset (abrupt, gradual, intermittent), and degree of variability from night to night. (See 'Approach to the sleep history' above.)
●Difficulties initiating or maintaining sleep (sleeplessness or insomnia) often have behavioral origins in young children. These issues can be identified by evaluating the sleep schedule, sleeping environment, and bedtime routines. Other causes or contributors in all age groups include psychosocial stressors, underlying medical problems, and anxiety or depression. Specific sleep disorders that may cause sleep-onset insomnia include restless legs syndrome (RLS) and delayed sleep-wake phase disorder, which is common in adolescents. (See 'Difficulty initiating or maintaining sleep' above and "Behavioral sleep problems in children".)
●The most common causes of daytime sleepiness include insufficient nocturnal sleep compared with the average sleep requirements for the age group (figure 1), poor sleep hygiene, and medication side effects. Less common but important causes include narcolepsy, obstructive sleep apnea (OSA), idiopathic hypersomnia, and periodic limb movement disorder (PLMD). (See 'Excessive daytime sleepiness' above.)
●OSA in children typically presents with snoring, other noisy breathing, daytime behavioral problems, or excessive daytime sleepiness. If these symptoms are present, or if a child has significant adenotonsillar hypertrophy or obesity, a more detailed clinical evaluation is warranted. (See 'Obstructive sleep apnea' above and "Evaluation of suspected obstructive sleep apnea in children".)
●Abnormal movements or behaviors may be observed in a variety of sleep disorders, including rhythmic movement disorder, parasomnias (sleepwalking, confusional arousals, and night terrors), and nocturnal seizures (table 3). (See 'Movements or behaviors during sleep' above.)
•Rhythmic movements of the head, neck, or trunk associated with sleep are common and likely developmental (physiologic) in infants and young children. They are most common in infants and toddlers, and generally resolve spontaneously by five years of age. (See 'Periodic or rhythmic movements' above.)
•RLS and periodic limb movements in sleep are relatively common in children and are associated with diminished attentiveness. Children with RLS often have depressed serum ferritin levels, indicating reduced iron stores, and in this case the disorder may improve with iron supplementation. (See 'Periodic or rhythmic movements' above.)
•Compared with parasomnias, nocturnal seizures are more likely to recur during the same night, have stereotypic behaviors that look exactly the same each time, and occur randomly through the night (rather than in the first one-third of the night) (table 6). (See 'Complex movements or behaviors' above.)
●In some children, evaluation with overnight polysomnography (PSG) may be required to confirm a specific sleep disorder (eg, OSA or narcolepsy) or to titrate positive airway pressure. PSG is not routinely indicated for children with insomnia, circadian rhythm sleep disturbances, uncomplicated parasomnias, or behavioral sleep problems. (See 'Polysomnography' above.)
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