Narcolepsy in childhood

Development and validation of the narcolepsy severity scale in school aged children

OBJECTIVE

To develop and psychometrically test the pediatric narcolepsy severity scale (P-NSS) for pediatric with narcolepsy type 1 (NT1).

METHODS

Item pool was formed based on literature review, clinical judgement of the expert panel and input of the narcoleptic patients and their parents. Psychometric properties were evaluated after applying the P-NSS in a sample of 200 patients (8-18 years age) with narcolepsy. Analyses included item analysis, validity analysis and reliability analysis.

RESULTS

P-NSS consisted four factors with a total of 17 items. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) revealed four distinct and theoretically coherent factors, explaining 63.4% of the total variance. The fitting results of the CFA model were χ2/dƒ = 2.235, GFI = 0.876, AGFI = 0.822, RMSEA = 0.079, TLI = 0.908, CFI = 0.927. P-NSS score is correlated with Pediatric Daytime Sleepiness Scale (r = 0.512, P < 0.01), Epworth Sleepiness Scale for Children and Adolescents (r = 0.355, P < 0.01) and Narcolepsy quality-of-life instrument with 21 questions (r = -0.512, P < 0.01). Cronbach's α coefficient for P-NSS and four dimensions were from 0.732 to 0.915. The split-half reliability was 0.882 (P < 0.01).

CONCLUSION

P-NSS is proved to be a reliable and valid measure for Chinese children with NT1. It may serve in China as a valuable and easily accessible outcome measure for using in narcolepsy trials, the clinic with improved responsiveness and long term follow-up.

Approach to a sleepy child: Diagnosis and treatment of excessive daytime sleepiness in children and adolescents

The aim of this review is to give updated information to pediatric neurologists on the correct diagnostic approach and treatment of excessive daytime sleepiness (EDS) in children and adolescents. Due to the change in the society habits, EDS is becoming an emerging problem for the health system. At the present there are few articles specifically devoted to the evaluation of EDS. EDS is often reported in several manuscripts as a side effect of other sleep disorders (obstructive sleep apnea, circadian disorders, etc.) or of the use of drugs or of the substance abuse or as a consequence of bad sleep habits and poor sleep hygiene. EDS, especially in children, may manifest with paradoxical symptoms like hyperactivity, inattention, and impulsiveness. However, common sign of EDS in children are the propensity to sleep longer than usual, the difficulty waking up in the morning, and falling asleep frequently during the day in monotonous situation. The diagnosis should include subjective (sleep diaries, questionnaires) and objective (polysomnography, multiple sleep latency test, etc.) instruments to avoid misdiagnosis. Narcolepsy is the most studied central disorder of hypersomnolence, and it is a predominantly pediatric disease with a peak age of onset in prepuberty but the diagnosis is often delayed especially in mild forms. The early and correct treatment of narcolepsy and of other form of EDS is extremely important since late and inappropriate treatments can affect the psychosocial development of the children and adolescents.

The impact of narcolepsy on social relationships in young adults

STUDY OBJECTIVES

Narcolepsy often begins during adolescence and young adulthood, which are crucial periods for social development. The symptoms of narcolepsy likely impact social interactions, but little research has assessed the effects of narcolepsy on social relationships. The current study investigated the impact of narcolepsy on friendships and romantic and sexual relationships.

METHODS

Young adults (18-39 years) with narcolepsy were recruited through national narcolepsy patient organizations. Participants (n = 254) completed an online survey assessing their friendships and romantic and sexual relationships, including communication about their social relationships with medical providers.

RESULTS

All participants (mean age = 28.8 years; 87% female, 92% White/Caucasian) reported that narcolepsy made their social life more challenging. They reported receiving more support from significant others, compared to family or friends (P < .05). Most (80%) indicated that narcolepsy currently impacted their sex life. Only a few participants reported that their providers asked about their social and sex lives, though they wanted providers to ask.

CONCLUSIONS

Narcolepsy impacts social functioning in young adults. Many individuals with narcolepsy prioritize single, meaningful, romantic relationships as developing and sustaining new relationships may be challenging. In addition, narcolepsy symptoms impact sexual functioning. Though many participants wanted to discuss their social and sex lives with providers, only a few providers ask. Treatment of narcolepsy in young adulthood should include supporting individuals regarding the impact on social, romantic, and sexual health.

CITATION

Davidson RD, Biddle K, Nassan M, Scammell TE, Zhou ES. The impact of narcolepsy on social relationships in young adults. J Clin Sleep Med. 2022;18(12):2751-2761.

Secondary Narcolepsy as Worsening Sign in a Pediatric Case of Optic Pathway Glioma

Narcolepsy, a neurologic disorder that leads to excessive daytime sleepiness, may represent a rare consequence of neoplastic lesions involving the sellar/parasellar and hypothalamic regions, the anatomical areas responsible for wakefulness. Optic pathway gliomas represent the most common neoplasm of these regions and present an excellent overall survival, while long-term neurologic impairments, such as visual loss, endocrinopathies, or sleep disorders, are the principal causes of morbidity. In this case report, we describe a non-NF1 patient suffering from a very extensive optical pathway glioma, who several years after the diagnosis in a radiological condition of stable disease, presented with severe narcolepsy, a rare complication, that led to the death of the patient.

Narcolepsy in Children: Sleep disorders in children, A rapidly evolving field seeking consensus

Narcolepsy is a life-long sleep disorder with two distinct subtypes, narcolepsy type I and narcolepsy type II. It is now well recognized that the loss of hypocretin neurons underlies the pathogenesis of narcolepsy type I, however, the pathogenesis of narcolepsy type II is currently unknown. Both genetic and environmental factors play an important role in the pathogenesis of narcolepsy. There is increasing evidence that autoimmune processes may play a critical role in the loss of hypocretin neurons. Infections especially streptococcus and influenza have been proposed as a potential trigger for the autoimmune-mediated mechanism. Several recent studies have shown increased cases of pediatric narcolepsy following the 2009 H1N1 pandemic. The increased cases in Europe seem to be related to a specific type of H1N1 influenza vaccination (Pandemrix), while the increased cases in China are related to influenza infection. Children with narcolepsy can have an unusual presentation at disease onset including complex motor movements which may lead to delayed diagnosis. All classic narcolepsy tetrads are present in only a small proportion of children. The diagnosis of narcolepsy is confirmed by either obtaining cerebrospinal fluid hypocretin or overnight sleep study with the multiple sleep latency test (MSLT). There are limitations of using MSLT in young children such that a negative MSLT test cannot exclude narcolepsy. HLA markers have limited utility in narcolepsy, but it may be useful in young children with clinical suspicion of narcolepsy. For management, both pharmacologic and non-pharmacologic treatments are important in the management of narcolepsy. Pharmacotherapy is primarily aimed to address excessive daytime sleepiness and REM-related symptoms such as cataplexy. In addition to pharmacotherapy, routine screening of behavioral and psychosocial issues is warranted to identify patients who would benefit from bio-behavior intervention.

Pediatric Narcolepsy-A Practical Review

Pediatric narcolepsy is a chronic sleep-wakefulness disorder. Its symptoms frequently begin in childhood. This review article examined the literature for research reporting on the effects of treatment of pediatric narcolepsy, as well as proposed etiology and diagnostic tools. Symptoms of pediatric narcolepsy include excessive sleepiness and cataplexy. In addition, rapid-eye-movement-related phenomena such as sleep paralysis, sleep terror, and hypnagogic or hypnapompic hallucinations can also occur. These symptoms impaired children's function and negatively influenced their social interaction, studying, quality of life, and may further lead to emotional and behavioral problems. Therefore, early diagnosis and intervention are essential for children's development. Moreover, there are differences in clinical experiences between Asian and Western population. The treatment of pediatric narcolepsy should be comprehensive. In this article, we review pediatric narcolepsy and its treatment approach: medication, behavioral modification, and education/mental support. Pharmacological treatment including some promising newly-developed medication can decrease cataplexy and daytime sleepiness in children with narcolepsy. Other forms of management such as psychosocial interventions involve close cooperation between children, school, family, medical personnel, and can further assist their adjustment.

Narcolepsia na Infância: A Atuação Multidisciplinar com a Psicologia do Sono do Diagnóstico ao Tratamento em um Relato de Caso

Resumo A narcolepsia, distúrbio neurológico crônico caracterizado pela sonolência diurna excessiva, pode ser associada à cataplexia, fragmentação do sono, alucinações relacionadas ao sono e paralisia do sono. Frequentemente, é confundida com outros transtornos, como Transtorno do Déficit de Atenção com Hiperatividade (TDAH), epilepsia e até esquizofrenia, assim, por vezes, é diagnosticada inadequadamente. Objetiva-se relatar o diagnóstico diferencial bem-sucedido da narcolepsia na infância e suas dificuldades, realizado por uma equipe multidisciplinar, enfocando a atuação da psicologia do sono em avaliação e intervenção. Um menino de 10 anos foi recebido no Ambulatório de Narcolepsia e Apneia do Sono Infantil (AMBNAP), alocado no Hospital Universitário Onofre Lopes da Universidade Federal do Rio Grande do Norte (UFRN) com queixas de sonolência diurna excessiva, sono fragmentado e episódios de perda de tônus muscular. Foi submetido a entrevistas psiquiátrica e psicológica pormenorizadas, a exames, aplicação de escalas específicas para rastreio e diagnóstico de transtornos de sono e diário de sono, solicitação de recursos de mídia e de relatório escolar e avaliação neurológica. A partir da investigação multidisciplinar, o diagnóstico foi de Narcolepsia e Síndrome da Apneia Obstrutiva do Sono (SAOS). O paciente foi submetido a técnicas da Terapia Cognitivo-Comportamental (TCC) e segue em acompanhamento, apresentando resultados satisfatórios. Este estudo evidencia que uma equipe multidisciplinar especializada na área de sono atuando em conjunto com a Psicologia do Sono oportuniza o diagnóstico e intervenções precoces eficazes para o tratamento do distúrbio do sono na infância.

Paediatric narcolepsy: a review of diagnosis and management

Narcolepsy is a chronic disabling neurological sleep disorder that requires lifelong treatment. We have outlined the clinical features of narcolepsy, the assessment and diagnosis process and have summarised the existing treatment options for children and adolescents with narcolepsy. In the future, the approach to management of paediatric narcolepsy should ideally be in a multidisciplinary setting, involving specialists in sleep medicine, sleep physiology, neurologists and psychologists/psychiatrists. A multidisciplinary approach will help to manage the potential impact of narcolepsy on children and adolescents who are in a stage of their life that is critical to their physical, emotional and social development and their academic attainment.

Polysomnographic nighttime features of narcolepsy: A systematic review and meta-analysis

Polysomnographic studies have been conducted to explore nighttime sleep features in narcolepsy, but their relationship to narcolepsy is still imperfectly understood. We conducted a systematic review of the literature exploring polysomnographic differences between narcolepsy patients and healthy controls (HCs) in EMBASE, MEDLINE, All EBM databases, CINAHL, and PsycINFO. 108 studies were identified for this review, 105 of which were used for meta-analysis. Meta-analyses revealed significant reductions in sleep latency, sleep efficiency, slow wave sleep percentage, rapid eye movement sleep (REM) latency, cyclic alternating pattern rate, and increases in total sleep time, wake time after sleep onset (WASO), awakening numbers (AWN) per hour, stage shift (SS) per hour, N1 percentage, apnea hypopnea index, and periodic limb movement index in narcolepsy patients compared with HCs. Furthermore, narcolepsy type 1 patients showed more disturbed nighttime sleep compared with narcolepsy type 2 patients. Children and adolescent narcolepsy patients show increased WASO, AWN, and SS compared with adult patients. Macro- and micro-structurally, our study suggests that narcolepsy patients have poor nighttime sleep. Sex, age, body mass index, disease duration, disease type, medication status, and adaptation night are demographic, clinical and methodological factors that contribute to heterogeneity between studies.

The Impacts of Age and Sex in a Mouse Model of Childhood Narcolepsy

Narcolepsy is a sleep disorder caused by selective death of the orexin neurons that often begins in childhood. Orexin neuron loss disinhibits REM sleep during the active period and produces cataplexy, episodes of paralysis during wakefulness. Cataplexy is often worse when narcolepsy develops in children compared to adults, but the reason for this difference remains unknown. We used orexin-tTA; TetO DTA mice to model narcolepsy at different ages. When doxycycline is removed from the diet, the orexin neurons of these mice express diphtheria toxin A and die within 2-3 weeks. We removed doxycycline at 4 weeks (young-onset) or 14 weeks (adult-onset) of age in male and female mice. We implanted electroencephalography (EEG) and electromyography (EMG) electrodes for sleep recordings two weeks later and then recorded EEG/EMG/video for 24 h at 3 and 13 weeks after removal of doxycycline. Age-matched controls had access to doxycycline diet for the entire experiment. Three weeks after doxycycline removal, both young-onset and adult-onset mice developed severe cataplexy and the sleep-wake fragmentation characteristic of narcolepsy. Cataplexy and maintenance of wake were no worse in young-onset compared to adult-onset mice, but female mice had more bouts of cataplexy than males. Orexin neuron loss was similarly rapid in both young- and adult-onset mice. As age of orexin neuron loss does not impact the severity of narcolepsy symptoms in mice, the worse symptoms in children with narcolepsy may be due to more rapid orexin neuron loss than in adults.

Topical Review: A Biopsychosocial Framework for Pediatric Narcolepsy and Idiopathic Hypersomnia

OBJECTIVE

Provide an overview of current research findings in pediatric central disorders of hypersomnolence (CDH) and propose a biopsychosocial model for clinical management, with a focus on interdisciplinary care and future directions for research and clinical practice.

METHODS

Literature review drawing from pediatric and adult narcolepsy, as well as pediatric sleep and chronic pain research to develop an integrative biopsychosocial model for pediatric CDH.

RESULTS

Youth with CDH are vulnerable to impairments in academics, emotional, and behavioral functioning, activity engagement and quality of life (QOL). There is a complex interrelationship between neurobiological features of disease, treatment-related factors, and psychological, sleep-related, and contextual factors across development. Research is limited largely to adults and pediatric narcolepsy type 1 and the mechanisms and evolution of morbidity remain poorly understood.

CONCLUSIONS

In addition to first-line treatment (pharmacotherapy), routine screening of bio-behavioral and psychosocial functioning and QOL is needed to identify risk for compromised functioning warranting adjunctive interventions with behavioral health specialists.

Comorbidity of Narcolepsy and Psychotic Disorders: A Nationwide Population-Based Study in Taiwan

BACKGROUND

Narcolepsy is a chronic sleep disorder that is likely to have neuropsychiatric comorbidities. Psychotic disorders are characterized by delusion, hallucination, and reality impairments. This study investigates the relationship between narcolepsy and psychotic disorders.

DESIGN AND METHODS

This study involves patients who were diagnosed with narcolepsy between January 2002 and December 2011 (n = 258) and age- and gender-matched controls (n = 2580) from Taiwan's National Health Insurance database. Both the patients and the controls were monitored from January 1, 2002 to December 31, 2011 to identify any occurrence of a psychotic disorder. Drugs that have been approved for treating narcolepsy: immediate-release methylphenidate (IR-MPH), osmotic controlled-release formulations of methylphenidate (OROS-MPH), and modafinil, were analyzed. A multivariate logistic regression model was used to evaluate the potential comorbidity of narcolepsy with psychotic disorders.

RESULTS

During the study period, 8.1% of the narcoleptic patients exhibited comorbidity with a psychotic disorder, whereas only 1.5% of the control subjects (1.5%) had psychotic disorders (aOR, 4.07; 95% CI, 2.21-7.47). Of the narcolepsy patients, 41.5, 5.4, and 13.2% were treated with MPH-IR, MPH-OROS, and modafinil, accordingly. Pharmacotherapy for narcolepsy did not significantly affect the risk of exhibiting a psychotic disorder.

CONCLUSIONS

This nationwide study revealed that narcolepsy and psychotic disorders commonly co-occur. Pharmacotherapy for narcolepsy was not associated with the risk of psychotic disorders. Our findings serve as a reminder that clinicians must consider the comorbidity of narcolepsy and psychosis.

Autism Spectrum Disorder and Narcolepsy: A Possible Connection That Deserves to Be Investigated

Narcolepsy in childhood-adolescence is characterized by a high occurrence of psychiatric comorbidities. The most frequent psychiatric disorders reported in these patients are attention deficit/hyperactivity disorder, depression, anxiety disorder, and schizophrenia. However, narcolepsy can be associated also with introversion, sorrowfulness, feelings of inferiority, impaired affectivity modulation, emotional lability, irritability, aggressiveness, and poor attention, that have been pooled by some authors under a definition of "narcoleptic personality." Some aspects of this "narcoleptic personality," and in particular introversion, impaired affectivity modulation, irritability, and poor attention, partially overlap with the clinical features of the individuals with autism spectrum disorder, considering also those that are not regarded as core autism symptoms. Till now, in literature the number of cases affected by both narcolepsy and autism spectrum disorder (seven patients) has been clearly too small to demonstrate the presence of a pathogenetic link between these two conditions, but this possible connection has not yet been adequately investigated, despite the presence of several points in common. The finding of a connection between narcolepsy and autism spectrum disorder could boost the study of possible etiopathogenetic mechanisms shared between these two apparently so distant disorders. Basing on the literature data summarized in this paper, in the diagnostic work-up of a child with narcolepsy it is essential to evaluate also the social-communicative behavior using standardized tools in order to detect the real recurrence of clinical features suggesting an autism spectrum disorder. At the same time, it appears necessary to screen in the individuals with autism spectrum disorder for the possible presence of evoking symptoms of narcolepsy.

Obesity and other medical comorbidities among NT1 patients after the Norwegian H1N1 influenza epidemic and vaccination campaign

Study Objectives

Narcolepsy type 1 (NT1) may be complicated by comorbidities. We aimed to study the extent of obesity and other medical comorbidities in a Norwegian population of NT1 patients with debut of symptoms after the 2009 H1N1 influenza epidemic and vaccination campaign. We also aimed to explore factors associated with obesity.

Methods

Ninety-one patients (48 children and 43 adults) were included in this cross-sectional study, 80 of whom were H1N1-vaccinated. All participants were hospitalized and underwent sleep investigation and physical examination, and completed a semi-structured clinical interview.

Results

In children, 16 females (70%) and 10 males (40%) were classified as overweight or obese. Twenty children (42%) had a co-existing medical disorder. Medical comorbidity was significantly positively associated with BMI in children (p = .032). In adults, 19 females (58%) and 7 males (70%) were classified as overweight or obese. Twenty-six adults (61%) had a co-existing medical disorder. We found no factors significantly associated with BMI in adults. On a fatigue scale from 0 to 100, lower scores indicating more fatigue, we found a mean (SD) total fatigue score of 50 (17) in children and 39 (16) in adults.

Conclusion

In a cohort of predominantly H1N1-vaccinated NT1 patients, we found a high prevalence of overweight or obesity. Half of the cohort presented with one or more additional medical comorbidities, and patients reported a clinically relevant degree of fatigue. Our findings highlight the importance of carefully monitoring patients with NT1 with regard to the development of obesity, which is a significant risk factor for cardiovascular disorders.

Factors Influencing Time to Diagnosis in Childhood Narcolepsy Type 1

OBJECTIVE

To study the variables impacting on time from symptom onset to diagnosis in childhood narcolepsy, including presence of cataplexy, onset in infancy, administration of the H1N1 Pandemrix vaccine, and date of diagnosis following the H1N1 pandemic.

DESIGN

A retrospective cohort study of 42 children seen in a single tertiary pediatric neurology center between 1996 and 2016.

KEY RESULTS

Onset of symptoms of narcolepsy occurred between infancy and 15 years, with 92.9% of children symptomatic by 13 years. Time from reported symptom onset to diagnosis ranged from 3 months to 11 years, with 51.3% diagnosed within 12 months of symptom onset. Those patients who were reportedly symptomatic from birth had a statistically significant increased time from reported symptom onset to diagnosis.

CONCLUSIONS

The symptoms of childhood narcolepsy progress over time. The number of annual diagnoses in this center increased over the study period, but there is no evidence that the time from symptom onset to diagnosis is decreasing. Being reportedly symptomatic from the age of <1 year is associated with an increased time to diagnosis. We recommend raising awareness of narcolepsy among medical students and general practitioners. It is important that clinicians appreciate the clinical relevance of excessive daytime sleepiness.

Management of Excessive Daytime Sleepiness in Narcolepsy With Baclofen

BACKGROUND

Narcolepsy is a disabling sleep-wake disorder characterized by the pentad symptoms of excessive daytime sleepiness, sleep paralysis, sleep fragmentation, sleep-related hallucinations, and cataplexy. There is no curative therapy for narcolepsy. Treatment is therefore symptom directed. Symptom management is generally directed at improving excessive daytime sleepiness, sleep fragmentation, and cataplexy. First-line treatment for excessive daytime sleepiness is typically daily use of wake-promoting agents, such as modafinil or armodafinil, or stimulant therapy, such as methylphenidate or amphetamines. Alternatively, sodium oxybate can be used nightly for improved cataplexy, sleep consolidation, and following day wakefulness. These therapies can be limited in some patients because of inadequate efficacy, poor tolerability, or side effects.

METHODS

We describe five narcolepsy patients with severe excessive daytime sleepiness who had an inadequate response or experienced side effects with the initial therapies but had a positive response to treatment with baclofen.

RESULTS

These patients reported subjective improvement in sleep maintenance without fragmentation and daytime sleepiness. Average Epworth Sleepiness Scale assessment before treatment was 15.8 with post-treatment assessment being 10.4 (P < 0.05).

CONCLUSIONS

Baclofen may be an effective treatment for excessive daytime sleepiness and sleep fragmentation in narcolepsy and warrants further study.

Childhood narcolepsy and autism spectrum disorders: four case reports

BACKGROUND

Childhood narcolepsy is associated with various emotional, behavioural and cognitive dysfunctions as well as with psychiatric and neurodevelopmental disorders: anxiety, depression, attention deficit hyperactivity disorder and psychosis. A relationship between these conditions is unclear - comorbidity or similar pathophysiological mechanisms can be suggested.

OBJECTIVE

We reported four children with narcolepsy type 1 (NT1) and autism spectrum disorder (ASD) - Asperger syndrome (AS).

RESULTS AND CONCLUSION

To the best of our knowledge co-occurrence of NT1 and AS has not been described in the literature as noted in this report.

Clinical Characteristics and Burden of Illness in Pediatric Patients with Narcolepsy

BACKGROUND

Narcolepsy is a chronic and lifelong neurologic disorder with onset commonly occurring in childhood or adolescence, and affecting approximately 0.025% to 0.05% of the general population. The primary symptom is excessive daytime sleepiness, which is accompanied by cataplexy in 70% of patients. Other common symptoms include sleep paralysis, hallucinations upon falling asleep or waking, and disrupted nocturnal sleep. Narcolepsy is associated with a considerable burden of illness (BOI), which has been well characterized in adults, and is exacerbated by delays in symptom recognition, diagnosis, and intervention.

METHODS

This review describes the specific characteristics and BOI of pediatric narcolepsy, using a wide range of published research data.

RESULTS

Pediatric narcolepsy presents distinct challenges in diagnosis and management. Narcolepsy symptoms often initially manifest differently in children and adolescents versus adults, which may pose diagnostic dilemmas. Children often respond to sleepiness with irritability, hyperactivity, and poor attention, which may be misinterpreted as misbehavior or neurocognitive sequelae of other conditions. Pediatric cataplexy symptoms may include subtle and unusual facial expressions or choreic-like movements, which are not observed in adults. Insufficient sleep and circadian rhythm disorders presenting with excessive daytime sleepiness are common in adolescents, potentially confounding narcolepsy diagnosis. Pediatric narcolepsy is also associated with comorbidities including rapid weight gain, precocious puberty, and attention deficit hyperactivity disorder, and increased risk for deficits in social functioning, depression, and anxiety. School performance is also typically impaired, requiring special education services.

CONCLUSIONS

Thus, the discrete BOI of pediatric narcolepsy underscores the need for prompt and accurate diagnosis, and appropriate treatment of this disorder.

Correlates to Problem Behaviors in Pediatric Narcolepsy: A Pilot Study

STUDY OBJECTIVE

Excessive daytime sleepiness, the hallmark of narcolepsy, predisposes patients to serious performance decrements in multiple areas of function. Psychosocial dysfunction has been demonstrated in adults and children with narcolepsy. Several factors could influence psychosocial functioning in children. The objective of this study was to examine neurobehavioral problems in children with narcolepsy and to define associations with these problem behaviors.

METHODS

A cross-sectional study was performed where the Child Behavior Checklist (CBCL) was completed by guardians of children (age 18 years or younger) in whom narcolepsy with or without cataplexy was diagnosed (based on the International Classification of Sleep Disorders, Second Edition) between July 2008 and October 2014. Spearman correlations (continuous variables) and Wilcoxon rank-sum tests (categorical variables) were performed for the CBCL findings and narcolepsy factors previously shown to influence psychosocial functioning.

RESULTS

The participants' current age correlated significantly with multiple CBCL scales. Caregivers of younger participants reported higher total psychosocial problems and externalizing problems. In addition, caregivers of younger participants reported higher scores on indices measuring inattention, withdrawal, thought problems, aggression, and rule-breaking behaviors. Values of P < .001 were found for total psychosocial problems, externalizing behaviors, and thought problems (negative correlations of 0.66, 0.65, and 0.64, respectively).

CONCLUSIONS

Patients with pediatric narcolepsy have high rates of attention and emotional/behavior problems. These problems strongly correlated with age. Younger children expressed higher emotional, behavioral, and attention problems. Sleep physicians need to be aware of and assess the mental and behavioral health of their pediatric patients with narcolepsy.

Comorbidity of narcolepsy and depressive disorders: a nationwide population-based study in Taiwan

OBJECTIVE

Narcolepsy is a chronic sleep disorder that is likely to have neuropsychiatric comorbidities. Depression is a serious mood disorder that affects individuals' daily activities and functions. The current study aimed to investigate the relationship between narcolepsy and depressive disorders.

METHODS

The study consisted of patients diagnosed with narcolepsy between January 2002, and December 2011 (n = 258), and age-matched and gender-matched controls (n = 2580) from Taiwan's National Health Insurance database. Both the patients and the controls were monitored through December 31, 2011, to identify the occurrence of a depressive disorder. A multivariate logistic regression model was used to assess the narcolepsy's potential influence on the comorbidity of a depressive disorder.

RESULTS

During the study period, 32.7%, 24.8%, and 10.9% of the narcoleptic patients were comorbid with any depressive disorder, dysthymic disorder, and major depressive disorder, respectively. When compared to the control subjects, the patients with narcolepsy were at greater risks of having any depressive disorder (aOR 6.77; 95% CI 4.90-9.37), dysthymic disorder (aOR 6.62; 95% CI 4.61-9.57), and major depressive disorder (aOR 6.83; 95% CI 4.06-11.48). Of the narcoleptic patients that were comorbid with depression, >50% had been diagnosed with depression prior to being diagnosed with narcolepsy.

CONCLUSIONS

This nationwide data study revealed that narcolepsy and depression commonly co-occurred. Since some symptoms of narcolepsy overlapped with those of depressive disorders, the findings serve as a reminder that clinicians must pay attention to the comorbidity of narcolepsy and depression.

Clinical and polysomnographic characteristics of excessive daytime sleepiness in children

PURPOSE

This study aimed to delineate the clinical and polysomnography (PSG) characteristics of sleep disorders in children with excessive daytime sleepiness (EDS).

METHODS

Between February 2002 and June 2015, 622 pediatric patients with EDS were evaluated with overnight PSG and the Multiple Sleep Latency Test at the Samsung Medical Center. The medical records; questionnaire responses about depression, sleepiness, sleep habits; and sleep study data of 133 patients without obstructive sleep apnea (OSA) were reviewed retrospectively.

RESULTS

The patients (63 girls, 70 boys) slept for an average of 7 h 30 min and 8 h 44 min on weekdays and weekends, respectively. The mean Epworth Sleepiness Scale score was 11.01 ± 4.09 and did not differ significantly among sleep disorders. Among the 102 patients who completed the depression questionnaire, 53 showed depressive feelings, which were moderate or severe in 39, with no significant differences among specific sleep disorders. Thirty-four patients exhibited normal PSG results. Seventeen of them were concluded as not having any sleep disorders, and the others as having delayed sleep phase disorder (DSPD). Narcolepsy (n = 78) was the most common disorder, followed by DSPD (n = 17) and idiopathic hypersomnia (n = 12).

CONCLUSIONS

Pediatric patients with EDS had various sleep disorders and some did not have any sleep disorder despite EDS. More than half the patients with EDS showed depressive feelings affecting their daily lives. For pediatric patients with EDS, a systematic diagnostic approach including questionnaires for sleep habits and emotion and PSG is essential for accurate diagnosis and treatment.

The spectrum of REM sleep-related episodes in children with type 1 narcolepsy

Type 1 narcolepsy is a central hypersomnia due to the loss of hypocretin-producing neurons and characterized by cataplexy, excessive daytime sleepiness, sleep paralysis, hypnagogic hallucinations and disturbed nocturnal sleep. In children, close to the disease onset, type 1 narcolepsy has peculiar clinical features with severe cataplexy and a complex admixture of movement disorders occurring while awake. Motor dyscontrol during sleep has never been systematically investigated. Suspecting that abnormal motor control might affect also sleep, we systematically analysed motor events recorded by means of video polysomnography in 40 children with type 1 narcolepsy (20 females; mean age 11.8 ± 2.6 years) and compared these data with those recorded in 22 age- and sex-matched healthy controls. Motor events were classified as elementary movements, if brief and non-purposeful and complex behaviours, if simulating purposeful behaviours. Complex behaviours occurring during REM sleep were further classified as 'classically-defined' and 'pantomime-like' REM sleep behaviour disorder episodes, based on their duration and on their pattern (i.e. brief and vivid-energetic in the first case, longer and with subcontinuous gesturing mimicking daily life activity in the second case). Elementary movements emerging either from non-REM or REM sleep were present in both groups, even if those emerging from REM sleep were more numerous in the group of patients. Conversely, complex behaviours could be detected only in children with type 1 narcolepsy and were observed in 13 patients, with six having 'classically-defined' REM sleep behaviour disorder episodes and seven having 'pantomime-like' REM sleep behaviour disorder episodes. Complex behaviours during REM sleep tended to recur in a stereotyped fashion for several times during the night, up to be almost continuous. Patients displaying a more severe motor dyscontrol during REM sleep had also more severe motor disorder during daytime (i.e. status cataplecticus) and more complaints of disrupted nocturnal sleep and of excessive daytime sleepiness. The neurophysiological hallmark of this severe motor dyscontrol during REM sleep was a decreased atonia index. The present study reports for the first time the occurrence of a severe and peculiar motor disorder during REM sleep in paediatric type 1 narcolepsy and confirms the presence of a severe motor dyscontrol in these patients, emerging not only from wakefulness (i.e. status cataplecticus), but also from sleep (i.e. complex behaviours during REM sleep). This is probably related to the acute imbalance of the hypocretinergic system, which physiologically acts by promoting movements during wakefulness and suppressing them during sleep.

Narcolepsy and cataplexy: a pediatric case report

Narcolepsy is characterized by excessive sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis during the rapid eye movement period of sleep. Herein, we present a boy aged eight years who was diagnosed as having narcolepsy and cataplexy about thirteen months after his first presentation. He was admitted with symptoms of daytime sleepiness. In the follow-up, cataplexy in the form of head dropping attacks developed seven months after the first admission. The patient was investigated for different prediagnoses and was eventually diagnosed as having narcolepsy and cataplexy through polysomnography and multiple sleep latency tests thirteen months after the first presentation. He is being followed up and is under drug therapy; his symptoms have improved substantially.

Circadian Rest-Activity Rhythm in Pediatric Type 1 Narcolepsy

STUDY OBJECTIVES

Pediatric type 1 narcolepsy is often challenging to diagnose and remains largely undiagnosed. Excessive daytime sleepiness, disrupted nocturnal sleep, and a peculiar phenotype of cataplexy are the prominent features. The knowledge available about the regulation of circadian rhythms in affected children is scarce. This study compared circadian rest-activity rhythm and actigraphic estimated sleep measures of children with type 1 narcolepsy versus healthy controls.

METHODS

Twenty-two drug-naïve type 1 narcolepsy children and 21 age- and sex- matched controls were monitored for seven days during the school week by actigraphy. Circadian activity rhythms were analyzed through functional linear modeling; nocturnal and diurnal sleep measures were estimated from activity using a validated algorithm.

RESULTS

Children with type 1 narcolepsy presented an altered rest-activity rhythm characterized by enhanced motor activity throughout the night and blunted activity in the first afternoon. No difference was found between children with type 1 narcolepsy and controls in the timing of the circadian phase. Actigraphic sleep measures showed good discriminant capabilities in assessing type 1 narcolepsy nycthemeral disruption.

CONCLUSIONS

Actigraphy reliably renders the nycthemeral disruption typical of narcolepsy type 1 in drug-naïve children with recent disease onset, indicating the sensibility of actigraphic assessment in the diagnostic work-up of childhood narcolepsy type 1.

Antibodies to influenza nucleoprotein cross-react with human hypocretin receptor 2

The sleep disorder narcolepsy is linked to the HLA-DQB1*0602 haplotype and dysregulation of the hypocretin ligand-hypocretin receptor pathway. Narcolepsy was associated with Pandemrix vaccination (an adjuvanted, influenza pandemic vaccine) and also with infection by influenza virus during the 2009 A(H1N1) influenza pandemic. In contrast, very few cases were reported after Focetria vaccination (a differently manufactured adjuvanted influenza pandemic vaccine). We hypothesized that differences between these vaccines (which are derived from inactivated influenza viral proteins) explain the association of narcolepsy with Pandemrix-vaccinated subjects. A mimic peptide was identified from a surface-exposed region of influenza nucleoprotein A that shared protein residues in common with a fragment of the first extracellular domain of hypocretin receptor 2. A significant proportion of sera from HLA-DQB1*0602 haplotype-positive narcoleptic Finnish patients with a history of Pandemrix vaccination (vaccine-associated narcolepsy) contained antibodies to hypocretin receptor 2 compared to sera from nonnarcoleptic individuals with either 2009 A(H1N1) pandemic influenza infection or history of Focetria vaccination. Antibodies from vaccine-associated narcolepsy sera cross-reacted with both influenza nucleoprotein and hypocretin receptor 2, which was demonstrated by competitive binding using 21-mer peptide (containing the identified nucleoprotein mimic) and 55-mer recombinant peptide (first extracellular domain of hypocretin receptor 2) on cell lines expressing human hypocretin receptor 2. Mass spectrometry indicated that relative to Pandemrix, Focetria contained 72.7% less influenza nucleoprotein. In accord, no durable antibody responses to nucleoprotein were detected in sera from Focetria-vaccinated nonnarcoleptic subjects. Thus, differences in vaccine nucleoprotein content and respective immune response may explain the narcolepsy association with Pandemrix.

Narcolepsy in a three-year-old girl: A case report

OBJECTIVE

Narcolepsy is characterized by excessive daytime somnolence associated with sleep paralysis, hallucinations when falling asleep or awakening, and cataplexy. Early recognition of pediatric narcolepsy is essential for growth and development. We experienced a case of narcolepsy in a three-year-old girl.

METHODS

The patient underwent brain MRI and 24h video-electroencephalogram (EEG) monitoring. Polysomnography (PSG) with multiple sleep latency test (MSLT) and human leukocyte antigen (HLA) DQ typing was performed.

RESULTS

The brain MRI was normal. 24h video-EEG monitoring revealed no abnormal slow or epileptiform discharge on interictal EEG, and no EEG change during tongue thrusting, dropping head with laughter, or flopping down, which was consistent with cataplexy associated with narcolepsy. A mean sleep latency of 2.5 min and four episodes of sleep-onset REM periods in five naps were observed in PSG with MSLT. She was positive in HLA-DQB1*0602. Based on these findings, she was diagnosed as narcoleptic with cataplexy.

CONCLUSION

The history, combined with PSG and MSLT, was helpful in the diagnosis of narcolepsy. We report a case of early-onset narcolepsy presenting with excessive sleepiness and cataplexy.

Challenges in the development of therapeutics for narcolepsy

Narcolepsy is a neurological disorder that afflicts 1 in 2000 individuals and is characterized by excessive daytime sleepiness and cataplexy-a sudden loss of muscle tone triggered by positive emotions. Features of narcolepsy include dysregulation of arousal state boundaries as well as autonomic and metabolic disturbances. Disruption of neurotransmission through the hypocretin/orexin (Hcrt) system, usually by degeneration of the HCRT-producing neurons in the posterior hypothalamus, results in narcolepsy. The cause of Hcrt neurodegeneration is unknown but thought to be related to autoimmune processes. Current treatments for narcolepsy are symptomatic, including wake-promoting therapeutics that increase presynaptic dopamine release and anticataplectic agents that activate monoaminergic neurotransmission. Sodium oxybate is the only medication approved by the US Food and Drug Administration that alleviates both sleep/wake disturbances and cataplexy. Development of therapeutics for narcolepsy has been challenged by historical misunderstanding of the disease, its many disparate symptoms and, until recently, its unknown etiology. Animal models have been essential to elucidating the neuropathology underlying narcolepsy. These models have also aided understanding the neurobiology of the Hcrt system, mechanisms of cataplexy, and the pharmacology of narcolepsy medications. Transgenic rodent models will be critical in the development of novel therapeutics for the treatment of narcolepsy, particularly efforts directed to overcome challenges in the development of hypocretin replacement therapy.

Allergies and Disease Severity in Childhood Narcolepsy: Preliminary Findings

INTRODUCTION

Narcolepsy frequently begins in childhood, and is characterized by excessive daytime sleepiness, with the presence of cataplexy reflecting a more severe phenotype. Narcolepsy may result from genetic predisposition involving deregulation of immune pathways, particularly involving T helper 2 cells (Th2). Increased activation of Th2 cells is usually manifested as allergic conditions such as rhinitis, atopic dermatitis, and asthma. We hypothesized that the presence of allergic conditions indicative of increased Th2 balance may dampen the severity of the phenotype in children with narcolepsy.

METHODS

A retrospective chart review of childhood narcolepsy patients was conducted at three major pediatric sleep centers. Patients were divided into those with narcolepsy without cataplexy (NC-) and narcolepsy with cataplexy (NC+). Demographics, polysomnographic and multiple sleep latency test data, and extraction of information on the presence of allergic diseases such allergic rhinitis, atopic dermatitis, and asthma was performed.

RESULTS

There were 468 children identified, with 193 children in NC- group and 275 patients in the NC+ group. Overall, NC+ children were significantly younger, had higher body mass index, and had shorter mean sleep latencies and increased sleep onset rapid eye movement events. The frequency of allergic conditions, particularly asthma and allergic rhinitis, was markedly lower in NC+ (58/275) compared to NC- patients (94/193; P < 0.0001).

CONCLUSION

Involvement of the immune system plays an important role in the pathophysiology of narcolepsy. Current findings further suggest that an increased shift toward T helper 2 cells, as indicated by the presence of allergic conditions, may modulate the severity of the phenotype in childhood narcolepsy, and reduce the prevalence of cataplexy in these patients.

Psychosocial Characteristics of Children with Central Disorders of Hypersomnolence Versus Matched Healthy Children

BACKGROUND

Hypersomnia of central origin from narcolepsy or idiopathic hypersomnia (IHS) is characterized by pathological levels of excessive daytime sleepiness (EDS). Central hypersomnia has historically been underdiagnosed and poorly understood, especially with respect to its impact on daytime functioning and quality of life in children.

OBJECTIVE

Describe the psychosocial adjustment of children treated for narcolepsy or IHS on school performance, quality of life, and physical/extracurricular activities.

METHODS

Using a matched case control design, we compared child self- and parent-reported data from thirty-three 8- to 16-year-olds with an established diagnosis of narcolepsy or IHS, according to ICSD-2 criteria, to that of 33 healthy children matched by age, race/ethnicity, gender, and household income. Assessments evaluated academic performance, quality of life and wellness, sleepiness, and participation in extracurricular activities.

RESULTS

Compared to healthy controls, children with central hypersomnia had poorer daytime functioning in multiple domains. Children with hypersomnia missed more days of school and had lower grades than healthy controls. Children with hypersomnia had poorer quality of life by both parent and child report. Children with hypersomnia were significantly sleepier, had higher BMI, and were more likely to report a history of recent injury. Finally, children with hypersomnia engaged in fewer after-school activities than healthy controls.

CONCLUSIONS

A range of significant psychosocial consequences are reported in children with hypersomnia even after a diagnosis has been made and treatments initiated. Health care professionals should be mindful of the psychosocial problems that may present in children with hypersomnia over the course of treatment.

Case report of narcolepsy in a six-year-old child initially misdiagnosed as atypical epilepsy

Summary

This report describes a case of first-onset narcolepsy in a six-year-old female that was misdiagnosed as atypical epilepsy and other diagnoses at eight different hospitals over a period of 10 months before the correct diagnosis was made. The diagnosis of narcolepsy is more difficult in children because very few of them experience all four cardinal symptoms of narcolepsy – paroxysmal sleep, cataplexy, hypnagogic hallucination, and sleep paralysis – and they often have a more prolonged onset and diverse symptoms. To decrease the time lag between initial presentation and accurate diagnosis, we recommend that in all cases in which children report excessive sleep of unknown etiology – regardless of the associated symptoms – that sleep monitoring and sleep latency tests be conducted to rule out the possibility of narcolepsy. The case highlights the wide variety of presentations of uncommon psychiatric conditions, particularly in children, and the need for clinicians to be aware of the atypical presentations of these conditions when collecting medical histories.

Narcolepsy in pediatric age - Experience of a tertiary pediatric hospital

Narcolepsy, a chronic disorder of the sleep–wake cycle of multifactorial etiology, is characterized by excessive daytime sleepiness, often associated with cataplexy, hypnagogic/hypnopompic hallucinations and sleep paralysis. Both early clinical suspicion and therapeutic approach are essential for promotion of cognitive development and social integration of these children. The authors present a descriptive retrospective study of a series of eight children in whom symptoms first started between 6.8 and 10.5 years of age. Diagnostic delay ranged from 4 months to 2 years. One child had H1N1 flu vaccination eight months before the clinical onset. The first multiple sleep latency test was positive in 6 of 8 cases. All cases were treated with methylphenidate, and venlafaxine was associated in 4 of them. In one case the initial therapy was exclusively behavioral. In all cases, symptomatic improvement, better school performance and social integration were achieved after therapeutic adjustment.

A retrospective survey of childhood ADHD symptomatology among adult narcoleptics

OBJECTIVE

This study examined the retrospective history of childhood ADHD symptomatology in an adult narcoleptic population (Narcolepsy Group [NG]: n = 161) compared with a control group (CG: n = 117).

METHOD

Both groups completed the Wender Utah Rating Scale (WURS), a retrospective self-report questionnaire indicating the presence of childhood ADHD symptomatology in adults.

RESULTS

Childhood ADHD symptoms were significantly greater in NG than CG (p < .001). Joint prevalence calculations of childhood ADHD symptomatology in NG were more than 8 to 15 times greater than expected. Among NG, those individuals with a greater score on the WURS, indicative of childhood ADHD symptomatology, also had shorter sleep onsets on the Multiple Sleep Latency Test, a common objective measure of sleepiness, t(97) = -7.11, p < .05.

CONCLUSION

It appears that self-reported childhood ADHD symptomatology history among adult narcoleptics is common. Future research is warranted with adult narcoleptics to elucidate the true nature of this.

High prevalence of precocious puberty and obesity in childhood narcolepsy with cataplexy

STUDY OBJECTIVES

We analyzed the potential predictive factors for precocious puberty, observed in some cases of childhood narcolepsy with cataplexy (NC) and for obesity, a much more common feature of NC, through a systematic assessment of pubertal staging, body mass index (BMI), and metabolic/endocrine biochemical analyses.

DESIGN

Cross-sectional on consecutive recruitment.

SETTING

Hospital sleep center and pediatric unit.

PATIENTS

Forty-three children and adolescents with NC versus 52 age-matched obese children as controls.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Patients underwent clinical interview, polysomnographic recordings, cerebrospinal fluid hypocretin-1 measurement, and human leukocyte antigen typing. Height, weight, arterial blood pressure, and Tanner pubertal stage were evaluated. Plasma lipid and glucose profiles were analyzed. When an altered pubertal development was clinically suspected, plasma concentrations of hypothalamic-pituitary-gonadal axis hormones were determined. Children with NC showed a high prevalence of overweight/obesity (74%) and a higher occurrence of precocious puberty (17%) than obese controls (1.9%). Isolated signs of accelerated pubertal development (thelarche, pubic hair, advanced bone age) were also present (41%). Precocious puberty was significantly predicted by a younger age at first NC symptom onset but not by overweight/obesity or other factors. In addition, overweight/obesity was predicted by younger age at diagnosis; additional predictors were found for overweight/obesity (short disease duration, younger age at weight gain and lower high-density lipoprotein cholesterol), which did not include precocious puberty. NC symptoms, pubertal signs appearance, and body weight gain developed in close temporal sequence.

CONCLUSIONS

NC occurring during prepubertal age is frequently accompanied by precocious puberty and overweight/obesity, suggesting an extended hypothalamic dysfunction. The severity of these comorbidities and the potential related risks require a multidiagnostic approach and a tailored therapeutic management.

The incidence of narcolepsy in Europe: before, during, and after the influenza A(H1N1)pdm09 pandemic and vaccination campaigns

BACKGROUND

In August 2010 reports of a possible association between exposure to AS03 adjuvanted pandemic A(H1N1)pdm09 vaccine and occurrence of narcolepsy in children and adolescents emerged in Sweden and Finland. In response to this signal, the background rates of narcolepsy in Europe were assessed to rapidly provide information for signal verification.

METHODS

We used a dynamic retrospective cohort study to assess the narcolepsy diagnosis rates during the period 2000-2010 using large linked automated health care databases in six countries: Denmark, Finland, Italy, the Netherlands, Sweden and the United Kingdom.

RESULTS

Overall, 2608 narcolepsy cases were identified in almost 280 million person years (PY) of follow up. The pooled incidence rate was 0.93 (95% CI: 0. 90-0.97) per 100,000 PY. There were peaks between 15 and 30 year of age (women>men) and around 60 years of age. In the age group 5-19 years olds rates were increased after the start of pandemic vaccination compared to the period before the start of campaigns, with rate ratios (RR) of 1.9 (95% CI: 1.1-3.1) in Denmark, 6.4 (95% CI: 4.2-9.7) in Finland and 7.5 (95% CI: 5.2-10.7) in Sweden. Cases verification in the Netherlands had a significant effect on the pattern of incidence over time.

CONCLUSIONS

The results of this incidence study provided useful information for signal verification on a population level. The safety signal of increased narcolepsy diagnoses following the start of the pandemic vaccination campaign as observed in Sweden and Finland could be observed with this approach. An increase in narcolepsy diagnoses was not observed in other countries, where vaccination coverage was low in the affected age group, or did not follow influenza A(H1N1)pdm09 vaccination. Patient level analyses in these countries are being conducted to verify the signal in more detail.

Treatment of dyssomnias and parasomnias in childhood

OPINION STATEMENT

Dyssomnias are sleep disorders associated with complaints of insomnia or hypersomnia. The daytime sleepiness of narcolepsy is treated by a combination of planned daytime naps, regular exercise medications such as modafinil, or salts of methylphenidate, or amphetamine. Cataplexy that accompanies narcolepsy is treated with anticholinergic agents, selective serotonin reuptake inhibitors, or sodium oxybate. Children with neurodevelopmental disabilities such as autism have sleep initiation and maintenance difficulties on a multifactorial basis, with favorable response to melatonin in some patients. Childhood onset restless legs syndrome is often familial, associated with systemic iron deficiency, and responsive to iron supplementation and gabapentin. Parasomnias are episodic phenomena events which occur at the sleep -- wake transition or by intrusion on to sleep. Arousal parasomnias such as confusional arousals and sleep walking can sometimes be confused with seizures. A scheme for differentiating arousal parasomnias from nocturnal seizures is provided. Since arousal parasomnias are often triggered by sleep apnea, restless legs syndrome, or acid reflux, treatment measures directed specifically at these disorders often helps in resolution. Clonazepam provided in a low dose at bedtime can also alleviate sleep walking and confusional arousals. Obstructive sleep apnea affects about 2 percent of children. Adeno-tonsillar hypertrophy, cranio-facial anomalies, and obesity are common predisposing factors. Mild obstructive sleep apnea can be treated using a combination of nasal corticosteroids and a leukotriene antagonist. Moderate to severe obstructive sleep apnea are treated with adeno-tonsillectomy, positive airway pressure breathing devices, or weight reduction as indicated. This paper provides an overview of the topic, with an emphasis on management steps. Where possible, the level of evidence for treatment recommendations is indicated.

Predictors of hypocretin (orexin) deficiency in narcolepsy without cataplexy

STUDY OBJECTIVES

To compare clinical, electrophysiologic, and biologic data in narcolepsy without cataplexy with low (≤ 110 pg/ml), intermediate (110-200 pg/ml), and normal (> 200 pg/ml) concentrations of cerebrospinal fluid (CSF) hypocretin-1.

SETTING

University-based sleep clinics and laboratories.

PATIENTS

Narcolepsy without cataplexy (n = 171) and control patients (n = 170), all with available CSF hypocretin-1.

DESIGN AND INTERVENTIONS

Retrospective comparison and receiver operating characteristics curve analysis. Patients were also recontacted to evaluate if they developed cataplexy by survival curve analysis.

MEASUREMENTS AND RESULTS

The optimal cutoff of CSF hypocretin-1 for narcolepsy without cataplexy diagnosis was 200 pg/ml rather than 110 pg/ml (sensitivity 33%, specificity 99%). Forty-one patients (24%), all HLA DQB1*06:02 positive, had low concentrations (≤ 110 pg/ml) of CSF hypocretin-1. Patients with low concentrations of hypocretin-1 only differed subjectively from other groups by a higher Epworth Sleepiness Scale score and more frequent sleep paralysis. Compared with patients with normal hypocretin-1 concentration (n = 117, 68%), those with low hypocretin-1 concentration had higher HLA DQB1*06:02 frequencies, were more frequently non-Caucasians (notably African Americans), with lower age of onset, and longer duration of illness. They also had more frequently short rapid-eye movement (REM) sleep latency (≤ 15 min) during polysomnography (64% versus 23%), and shorter sleep latencies (2.7 ± 0.3 versus 4.4 ± 0.2 min) and more sleep-onset REM periods (3.6 ± 0.1 versus 2.9 ± 0.1 min) during the Multiple Sleep Latency Test (MSLT). Patients with intermediate concentrations of CSF hypocretin-1 (n = 13, 8%) had intermediate HLA DQB1*06:02 and polysomnography results, suggesting heterogeneity. Of the 127 patients we were able to recontact, survival analysis showed that almost half (48%) with low concentration of CSF hypocretin-1 had developed typical cataplexy at 26 yr after onset, whereas only 2% had done so when CSF hypocretin-1 concentration was normal. Almost all patients (87%) still complained of daytime sleepiness independent of hypocretin status.

CONCLUSION

Objective (HLA typing, MSLT, and sleep studies) more than subjective (sleepiness and sleep paralysis) features predicted low concentration of CSF hypocretin-1 in patients with narcolepsy without cataplexy.

Tolerance and efficacy of sodium oxybate in childhood narcolepsy with cataplexy: a retrospective study

Narcolepsy with cataplexy is a sleep disorder characterized by excessive daytime sleepiness, irresistible sleep episodes, and sudden loss of muscle tone (cataplexy) mostly triggered by emotions. Narcolepsy with cataplexy is a disabling lifelong disorder frequently arising during childhood. Pediatric narcolepsy often results in severe learning and social impairment. Improving awareness about this condition increases early diagnosis and may allow patients to rapidly access adequate treatments, including pharmacotherapy and/or non-medication-based approaches. Even though children currently undergo pharmacotherapy, data about safety and efficacy in the pediatric population are scarce. Lacking international guidelines as well as drugs registered for childhood narcolepsy with cataplexy, physicians have no other alternative but to prescribe in an off-label manner medications identical to those recommended for adults. We retrospectively evaluated 27 children ranging from 6 to 16 years old, suffering from narcolepsy with cataplexy, who had been treated with off-label sodium oxybate and had been followed in a clinical setting. Throughout a semi-structured interview, we documented the good efficacy and tolerability of sodium oxybate in the majority of the patients. This study constitutes a preliminary step towards a further randomized controlled trial in childhood narcolepsy with cataplexy.