Hypersomnolence is defined in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition, as excessive sleepiness associated with lapses into sleep, feeling unrefreshed, and difficulty waking in the morning despite an adequate sleep time.1 Excessive sleepiness as a subjective complaint is common among adolescents in the United States.2 In one study, daytime sleepiness occurring more than once per week was noted by 45.7% of adolescents.3
The consequences of hypersomnolence are far-reaching and can include obesity, underperformance in school, motor vehicle crashes, and psychiatric sequelae. Analysis of data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development showed that shorter sleep duration in grade 3 was associated with increased likelihood of being overweight in grade 6, as was shorter sleep duration in grade 6.4 Pagel et al.3 reported that students endorsing constant daytime sleepiness had a lower grade point average even after controlling for socioeconomic factors. In a poll by the National Sleep Foundation, more than one-half of 10th to 12th graders reported drowsy driving in the past year.5 A cross-sectional study of 27,939 adolescents showed greater substance use and feelings of hopelessness, suicidal thoughts, and attempts in those sleeping 6 to 7 hours per night.6 Given the significant adverse consequences of hypersomnolence, it is important to assess for this in children and adolescents presenting for psychiatric evaluations.
The etiology of hypersomnolence in children and adolescents is multifactorial and can include central disorders of hypersomnolence, medical or psychiatric illnesses, and medications. According to the 2006 Sleep in America poll, a telephone survey of 1,602 adolescents across the US, 45% of adolescents reported obtaining insufficient sleep (defined as less than 8 hours) on school nights, with less sleep per night reported with increase in age.5 Although developmental aspects discussed below play a role in insufficient sleep, behavioral factors are also implicated. The latter include later bedtimes, which may be in part due to greater screen time on technological devices in an increasingly connected world.7
Developmental Aspects of Excessive Sleepiness
Sleep timing and duration in children and adolescents is influenced by development stage. Starting at puberty, most adolescents experience a sleep phase “delay” of up to 2 hours later than in middle childhood.8 Two factors play a role in this delay. First, nocturnal melatonin secretion shifts to a later time, which parallels a shift in circadian phase preference from morning to evening; this results in difficulty falling asleep earlier.8 Second, sleep pressure accumulates more slowly after puberty: after 14.5–18.5 hours spent awake, post-pubertal children take longer to fall asleep than do pre-pubertal children.9 This delayed sleep-wake phase tendency in the context of early school start times can lead to insufficient sleep which in turn can lead to daytime sleepiness.
Children and adolescents differ in the amount of sleep that they need. The American Academy of Sleep Medicine recommends 9 to 12 hours of sleep per night for children age 6 to 12 years and 8 to 10 hours for adolescents age 13 to 18 years.10 This recommendation is endorsed by the American Academy of Pediatrics.11
Given the biological changes in adolescence and the impact that daytime sleepiness can have on adolescent health, several medical professional societies have advocated for a delay in middle and high school start times. The American Academy of Sleep Medicine issued a position statement that middle and high school start times should be 8:30 am or later.12 This position is shared by the American Academy of Pediatrics,13 Society of Behavioral Medicine,14 and the American Medical Association.15 There is evidence of increased sleep duration with later school start times.16
Causes of Daytime Sleepiness
Insufficient sleep is the most common cause of daytime sleepiness.17 Although poor sleep hygiene is commonly encountered in general practice,18 central disorders of hypersomnolence are also part of the differential diagnosis. Central disorders of hypersomnolence are characterized by excessive daytime sleepiness not attributable to another sleep disorder such as sleep-related breathing disorder or circadian rhythm sleep-wake disorder. All these disorders have in common the complaint of excessive sleepiness defined in the International Classification of Sleep Disorders, 3rd edition (ISCD-3), as “daily episodes of an irrepressible need to sleep or daytime lapses into sleep.”19
Narcolepsy is characterized by excessive daytime sleepiness, sleep paralysis, hallucinations on falling asleep or awakening, and cataplexy. Although symptoms vary, excessive daytime sleepiness is always present and onset can be in children younger than age 15 years.18 Narcolepsy is divided into two types: narcolepsy type 1 is characterized by cataplexy (sudden loss of muscle tone triggered by an emotional event) and/or a low cerebrospinal hypocretin-1 level, whereas narcolepsy type 2 does not present with cataplexy and/or low hypocretin-1.20
Idiopathic hypersomnia (IH) characterizes people who have excessive daytime sleepiness of no apparent cause with prolonged nighttime sleep, but do not have cataplexy. Clinically, IH may present like narcolepsy type 2. However, unlike with narcolepsy, people with IH do not have rapid eye movement (REM) sleep during daytime naps. Their nighttime polysomnogram may be normal, and they often do not have sleep fragmentation as is seen in narcolepsy.20 Some people with IH may be diagnosed with narcolepsy in the future.21
Kleine-Levin syndrome (KLS) is rare (about 1.5 cases per million), generally appearing in adolescent boys. It is characterized by relapsing-remitting episodes of severe sleepiness, hyperphagia, hypersexuality, depressed mood, and psychotic symptoms. Episodes of hypersomnolence in KLS last for 2 days to 4 weeks, recur at least once per year, and are characterized by normalization of cognition and alertness in between episodes. In adolescents who develop the disorder, it generally spontaneously resolves by age 30 years.22
Sleep-related breathing disorders are an often-undiagnosed cause of daytime sleepiness in children.23 People with risk factors for sleep-related breathing disorders have a higher body mass index and are an African-American male.24 It should be noted that data on the association of body mass index with sleep-related breathing disorders for children compared to adults is less complete and a number of the studies investigating this association have methodological issues that may confound the findings.
Circadian rhythm sleep-wake disorders may also cause daytime sleepiness. Delayed sleep-wake phase disorder often starts in adolescence. Those affected often cannot sleep before 2 to 3 am and prefer wake times in the late morning or early afternoon. If allowed to sleep freely, they have normal sleep quantity and quality, but are sleepy if forced to follow conventional sleep-wake times.18
In younger children, behavioral insomnia of childhood may also be a cause of daytime sleepiness. This manifests as bedtime resistance or refusal, or frequent nighttime awakenings.17,25 It is important for the clinician to keep this in mind, as the prevalence of problematic nighttime awakenings and bedtime resistance is as high as 15%.25,26 See Table 1 for a summary of causes of daytime sleepiness.
Common Causes of Daytime Sleepiness in Children
Assessment of Hypersomnolence
The assessment of hypersomnolence requires thorough history-taking, physical examination, and the integration of subjective and objective measures of sleep. Because hypersomnolence can be caused by a wide range of etiologies, a thorough evaluation is important for accurate diagnosis of the cause.
The initial evaluation should include details of the patient's total daily sleep time, sleep habits (bedtime, sleep-onset time) both on school days and holidays/weekends, napping habits, reports of snoring and/or witnessed apneas from self or parents/caregivers, restless legs syndrome symptoms or twitching in sleep, and indications at night suggestive of gastrointestinal reflux, asthma, or pain. It is also important to know whether the sleep obtained is refreshing, whether the patient has any diagnosed comorbid medical conditions, and drug use including illicit drugs, prescription drugs, and caffeine.
The physical examination for hypersomnolence should assess for findings associated with obstructive sleep apnea, such as obesity, midface hypoplasia, micrognathia, tonsillar hypertrophy, deviated nasal septum, and mouth breathing.27
Subjective measures of sleep may help better qualify sleep practices that are contributing to daytime sleepiness. Sleep logs should estimate the number, timing, and duration of daily sleep episodes (including nighttime sleep, daytime naps, and wake periods), and possibly eating times. These can be done over days to months and can be validated using concurrent actigraphy. Although sleep logs do have the risk of being inaccurately completed, they can be helpful to identify chronic insufficient sleep.27
Sleepiness scales and questionnaires may also be helpful. The Pediatric Daytime Sleepiness Scale is specifically designed for measuring daytime sleepiness in school-aged children. The Childhood Sleep Habits Questionnaire is a 35-item questionnaire normed for children age 4 to 10 years that assesses sleep habits, sleep problems, and sleep practices.28 The Pediatric Sleep Questionnaire is normed for children age 2 to 18 years, and contains a 22-item sleep-related breathing disorder subscale, a 4-item daytime sleepiness subscale, and a 6-item inattention/hyperactive behavior subscale.23
Objective measures of sleep include actigraphy, Multiple Sleep Latency Test (MSLT), and polysomnography (PSG) (Table 2). Actigraphs are miniature wristwatch-like devices worn on the wrist or ankle that work on the premise that movement is a sign of wakefulness and lack of movement is a sign of sleep. Actigraphy allows one to obtain longitudinal data about sleep and wake over several days in the patient's home environment. It is useful supplemental data to a sleep log.27 The gold-standard for objective assessment in excessive daytime sleepiness is the MSLT combined with nocturnal PSG.27,29
Diagnostic Tests for the Evaluation of Sleep Disorders
Nocturnal PSG quantifies sleep and breathing abnormalities. It provides information regarding total sleep time, sleep efficiency, sleep onset latency, initial latency to REM sleep, apnea-hypopnea index, snoring, arousal index, periodic leg movement index, periodic leg movement arousal index, pulse oximetry data, end-tidal or transcutaneous carbon dioxide trends, body position, electroencephalogram abnormalities, and sleep staging. MSLT is done the day after PSG to ensure at least 6 to 7 hours of sleep the night before MSLT.
MSLT with a mean sleep latency (MSL) of less than or equal to 8 minutes is required for a diagnosis of narcolepsy.19,27 This does not rule out prior sleep deprivation; therefore, we recommend keeping sleep logs and using actigraphy monitoring for at least 1 week prior to MSLT to rule out insufficient sleep and/or sleep-wake disturbances as a potential cause for the MSLT findings.19 It is also possible to get a false-negative result, as some patients with central disorder of hypersomnolence may not consistently have a MSL less than or equal to the hypersomnia cutoff of 5 minutes. In comparison, healthy children should have an MSL of 15 to 20 minutes.29 To improve accuracy, antidepressants are ideally stopped for at least 2 weeks prior to testing, and stimulants are stopped ideally 2 weeks prior to MSLT. Urine toxicology may also be indicated to assess for substance use. Drawbacks to MSLT include the cost and labor required to perform it and sleep architecture disruption due to the number of sensors required.27 Age and other developmental factors should be accounted for while interpreting the findings of MSLTs: pre-pubertal children have a longer MSL that decreases as they pass through various Tanner stages of development.30
Management of Hypersomnolence
Management of hypersomnolence in children and adolescents relies on treating the underlying cause. Patients and caregivers should be educated about normal sleep requirements in the relevant age group(s) and encouraged to obtain sufficient sleep on a consistent basis. If there is an underlying medical or psychiatric cause, this should be addressed. Narcolepsy and IH are treated with stimulant medications, although these tend to be less effective in IH than in narcolepsy.21 No US Food and Drug Administration-approved medications exist for treatment of IH. Treatment of KLS can also involve the off-label use of stimulants or amantadine during episodes of sleepiness. Lithium is used off-label as a preventive agent for those with frequent sleepiness episodes associated with KLS.22 Sleep disturbed by periodic limb movements or restless legs syndrome is often treated (off-label in children) with dopaminergic medications, gabapentin, or benzodiazepines.17,21
There should be an emphasis on good sleep hygiene (Table 3).18 Recommendations include consistent sleep and wake times 7 days per week; avoiding large meals or strenuous exercise before bed; only using the bed for sleep; minimizing use of electronics 30 to 60 minutes before bedtime; having as much exposure to bright light as possible after waking; having a consistent bedtime routine; and keeping the bedroom cool, dark, and quiet. In addition, avoiding stimulants including caffeine and nicotine is also important. A recent prospective study found that reducing electronics use after 9 pm was associated with early sleep time and longer sleep duration.7
Principles of Sleep Hygiene
For behavioral insomnia of childhood, treatment involves behavioral measures and parent training. Behavioral measures include setting specific, consistent bedtimes and naptimes, a standardized bedtime routine, and extinction of behaviors such as needing a parent in the room for the child to fall asleep. Parent training involves guidance on consistent reinforcement of limits and extinction of problematic behaviors.25
Cognitive-behavioral therapy for insomnia (CBT-I) can be used in adolescents with hypersomnolence. It consists of psychoeducation and sleep hygiene, tracking of sleep using sleep logs, cognitive therapies addressing anxieties, and resistance of outside pressures that can affect either overall time allotted for sleep or sleep latency, limiting stimuli, and relaxation techniques. An example of the interventions used in a course of CBT-I for adolescents is available in the randomized controlled trial by deBruin et al,31 which also found that Internet-based CBT-I has similar positive outcomes to group therapy.
Treatment of delayed sleep-wake phase disorder requires slowly delaying the scheduled sleep time until the desired bedtime is reached and requires strict adherence to the new sleep schedule as even missing 1 day can return the adolescent to the old sleep pattern. Melatonin is helpful in advancing the circadian clock. Common doses of melatonin in studies of insomnia have been as low as 0.75 mg for children younger than age 6 years. Typical doses for children are approximately 2.5 to 3 mg. Typical doses for adolescents are 5 to 10 mg.32 In addition, anchoring waking time with exposure to bright light in the morning and avoiding exposure to light at nighttime can help advance the body clock.
Hypersomnolence in children and adolescents is highly prevalent and has far-reaching psychosocial and health consequences. Although hypersomnolence could be secondary to central disorders of hypersomnolence, these conditions are rare. The most common cause of hypersomnolence in these age groups is insufficient sleep, and given the potential risk of harm due to accidents and increased risk of psychiatric comorbidity associated with excessive daytime sleepiness, it is important for the clinician to assess patients' sleep habits and counsel them about the importance of obtaining sufficient sleep.
- American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Arlington, VA: American Psychiatric Publishing; 2013.
- Kolla BP, He J-P, Mansukhani MP, Kotagal S, Frye MA, Merikangas KR. Prevalence and correlates of hypersomnolence symptoms in US teens. J Am Acad Child Adolesc Psychiatry. 2019;58(7):712–720. doi:10.1016/j.jaac.2018.09.435 [CrossRef]. PMID: doi:10.1016/j.jaac.2018.09.435 [CrossRef]30768408
- Pagel JF, Forister N, Kwiatkowki C. Adolescent sleep disturbance and school performance: the confounding variable of socioeconomics. J Clin Sleep Med. 2007;3(1):19–23. PMID:17557448
- Lumeng JC, Somashekar D, Appugliese D, Kaciroti N, Corwyn RF, Bradley RH. Shorter sleep duration is associated with increased risk for being overweight at ages 9 to 12 years. Pediatrics. 2007;120(5):1020–1029. https://doi.org/10.1542/peds.2006-3295 PMID: doi:10.1542/peds.2006-3295 [CrossRef]17974739
- [No authors listed]. 2006 sleep in America poll–teens and sleep. Sleep Health. 2015;1(2):e5. https://doi.org/10.1016/j.sleh.2015.04.005 doi:10.1016/j.sleh.2015.04.005 [CrossRef]
- Winsler A, Deutsch A, Vorona RD, Payne PA, Szklo-Coxe M. Sleepless in Fairfax: the difference one more hour of sleep can make for teen hopelessness, suicidal ideation, and substance use. J Youth Adolesc. 2014;44(2):362–378. doi:10.1007/s10964-014-0170-3 [CrossRef]25178930
- Perrault AA, Bayer L, Peuvrier M, et al. Reducing the use of screen electronic devices in the evening is associated with improved sleep and daytime vigilance in adolescents. Sleep (Basel). 2019;42(9):1–10. https://doi.org/10.1093/sleep/zsz125 PMID:31260534
- Frey S, Balu S, Greusing S, Rothen N, Cajochen C. Consequences of the timing of menarche on female adolescent sleep phase preference. PLoS One. 2009;4(4):e5217–e5217. https://doi.org/10.1371/journal.pone.0005217 PMID: doi:10.1371/journal.pone.0005217 [CrossRef]19384418
- Taylor DJ, Jenni OG, Acebo C, Carskadon MA. Sleep tendency during extended wakefulness: insights into adolescent sleep regulation and behavior. J Sleep Res. 2005;14(3):239–244. https://doi.org/10.1111/j.1365-2869.2005.00467.x PMID: doi:10.1111/j.1365-2869.2005.00467.x [CrossRef]16120098
- Paruthi S, Brooks LJ, D'Ambrosio C, et al. Consensus statement of the American Academy of Sleep Medicine on the recommended amount of sleep for healthy children: methodology and discussion. J Clin Sleep Med. 2016;12(11):1549–1561. https://doi.org/10.5664/jcsm.6288 PMID: doi:10.5664/jcsm.6288 [CrossRef]27707447
- American Academy of Pediatrics. Recommended amount of sleep for pediatric populations. Pediatrics. 2016;138(2):e20161601. https://doi.org/10.1542/peds.2016-1601 PMID: doi:10.1542/peds.2016-1601 [CrossRef]27456512
- Watson NF, Martin JL, Wise MS, et al. American Academy of Sleep Medicine Board of Directors. Delaying middle school and high school start times promotes student health and performance: an American Academy of Sleep Medicine position statement. J Clin Sleep Med. 2017;13(4):623–625. https://doi.org/10.5664/jcsm.6558 PMID: doi:10.5664/jcsm.6558 [CrossRef]28416043
- Adolescent Sleep Working GroupCommittee on AdolescenceCouncil on School Health. School start times for adolescents. Pediatrics. 2014;134(3):642–649. https://doi.org/10.1542/peds.2014-1697 PMID: doi:10.1542/peds.2014-1697 [CrossRef]25156998
- Society of Behavioral Medicine. Start middle and high schools at 8:30 a.m. or later to promote student health and learning. https://www.sbm.org/UserFiles/file/late-school-start-statement-FINAL.pdf. Accessed November 5, 2019.
- Report 6 of the Council on Science and Public Health. Delaying school start time to alleviate adolescent sleep deprivation. https://www.ama-assn.org/sites/ama-assn.org/files/corp/media-browser/public/about-ama/councils/Council%20Reports/council-on-science-public-health/a16-csaph6.pdf. Accessed November 5, 2019.
- Boergers J, Gable CJ, Owens JA. Later school start time is associated with improved sleep and daytime functioning in adolescents. J Dev Behav Pediatr. 2014;35(1):11–17. https://doi.org/10.1097/DBP.0000000000000018 PMID: doi:10.1097/DBP.0000000000000018 [CrossRef]
- Meltzer LJ, Mindell JA. Sleep and sleep disorders in children and adolescents. Psychiatr Clin North Am. 2006;29(4):1059–1076. https://doi.org/10.1016/j.psc.2006.08.004 PMID: doi:10.1016/j.psc.2006.08.004 [CrossRef]17118282
- Kotagal S, Pianosi P. Sleep disorders in children and adolescents. BMJ. 2006;332(7545):828–832. https://doi.org/10.1136/bmj.332.7545.828 PMID: doi:10.1136/bmj.332.7545.828 [CrossRef]16601043
- Sateia MJ. International classification of sleep disorders-third edition: highlights and modifications. Chest. 2014;146(5):1387–1394. https://doi.org/10.1378/chest.14-0970 PMID: doi:10.1378/chest.14-0970 [CrossRef]25367475
- Khan Z, Trotti LM. Central disorders of hypersomnolence: focus on the narcolepsies and idiopathic hypersomnia. Chest. 2015;148(1):262–273. https://doi.org/10.1378/chest.14-1304 PMID: doi:10.1378/chest.14-1304 [CrossRef]26149554
- Millman RPWorking Group on Sleepiness in Adolescents/Young Adults; AAP Committee on Adolescence. Excessive sleepiness in adolescents and young adults: causes, consequences, and treatment strategies. Pediatrics. 2005;115(6):1774–1786. https://doi.org/10.1542/peds.2005-0772 PMID: doi:10.1542/peds.2005-0772 [CrossRef]15930245
- Arnulf I, Rico TJ, Mignot E. Diagnosis, disease course, and management of patients with Kleine-Levin syndrome. Lancet Neurol. 2012;11(10):918–928. https://doi.org/10.1016/S1474-4422(12)70187-4 PMID: doi:10.1016/S1474-4422(12)70187-4 [CrossRef]22995695
- Chervin RD, Hedger K, Dillon JE, Pituch KJ. Pediatric sleep questionnaire (PSQ): validity and reliability of scales for sleep-disordered breathing, snoring, sleepiness, and behavioral problems. Sleep Med. 2000;1(1):21–32. https://doi.org/10.1016/S1389-9457(99)00009-X PMID: doi:10.1016/S1389-9457(99)00009-X [CrossRef]10733617
- Lumeng JC, Chervin RD. Epidemiology of pediatric obstructive sleep apnea. Proc Am Thorac Soc. 2008;5(2):242–252. https://doi.org/10.1513/pats.200708-135MG PMID: doi:10.1513/pats.200708-135MG [CrossRef]18250218
- Thomas JH, Burgers DE. Sleep is an eye-opener: behavioral causes and consequences of hypersomnolence in children. Paediatr Respir Rev. 2018;25:3–8. PMID:27986503
- Mindell JA, Kuhn B, Lewin DS, Meltzer LJ, Sadeh AAmerican Academy of Sleep Medicine. Behavioral treatment of bedtime problems and night wakings in infants and young children. Sleep. 2006;29(10):1263–1276. PMID:17068979
- Kothare SV, Kaleyias J. The clinical and laboratory assessment of the sleepy child. Semin Pediatr Neurol. 2008;15(2):61–69. https://doi.org/10.1016/j.spen.2008.03.003 PMID: doi:10.1016/j.spen.2008.03.003 [CrossRef]18555192
- Spruyt K, Gozal D. Pediatric sleep questionnaires as diagnostic or epidemiological tools: a review of currently available instruments. Sleep Med Rev. 2011;15(1):19–32. https://doi.org/10.1016/j.smrv.2010.07.005 PMID: doi:10.1016/j.smrv.2010.07.005 [CrossRef]
- Littner MR, Kushida C, Wise M, et al. Standards of Practice Committee of the American Academy of Sleep Medicine. Practice parameters for clinical use of the multiple sleep latency test and the maintenance of wakefulness test. Sleep. 2005;28(1):113–121. https://doi.org/10.1093/sleep/28.1.113 PMID: doi:10.1093/sleep/28.1.113 [CrossRef]15700727
- Carskadon MA, Harvey K, Duke P, Anders TF, Litt IF, Dement WC. Pubertal changes in daytime sleepiness. Sleep. 1980;2(4):453–460. https://doi.org/10.1093/sleep/2.4.453 PMID: doi:10.1093/sleep/2.4.453 [CrossRef]7403744
- de Bruin EJ, Bögels SM, Oort FJ, Meijer Anne Marie. Efficacy of cognitive behavioral therapy for insomnia in adolescents: a randomized controlled trial with internet therapy, group therapy and a waiting list condition. Sleep. 2015;38(12):1913–1926. doi:10.5665/sleep.5240 [CrossRef] PMID: doi:10.5665/sleep.5240 [CrossRef]26158889
- Cummings CCanadian Paediatric Society; Community Paediatrics Committee. Melatonin for the management of sleep disorders in children and adolescents. Paediatr Child Health. 2012;17(6):331–336.
Common Causes of Daytime Sleepiness in Children
■ Difficulty falling asleep at night
■ Inadequate sleep hygiene
■ Behavioral insomnias of childhood
■ Inconsistency in bedtime routines and schedules
■ Late daytime naps
■ Engaging in stimulating activities before bedtime
■ Electronics use before bed
Diagnostic Tests for the Evaluation of Sleep Disorders
Measures movement as surrogate marker for wakefulness
||Multiple sensors measure sleep time, efficiency, latency
Can be used to measure sleep-related breathing abnormalities
|Multiple sleep latency test
||Multiple sensors measure time to fall asleep during multiple daytime naps
Should be done after polysomnography to ensure adequate sleep the night prior
Principles of Sleep Hygiene
■ Keep sleep/wake times consistent
■ Avoid large meals or exercise before bed
■ Only use the bed for sleep
■ Avoid stimulants at nighttime
■ Exposure to bright light after waking
■ Keep bedroom cool, dark, quiet
■ Reduce use of electronics before bedtime