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

Estimating the prevalence and clinical causality of obstructive sleep apnea in paediatric narcolepsy patients

BACKGROUND

Numerous risk factors in paediatric narcolepsy may predispose them to obstructive sleep apnea (OSA). The concurrent presence of OSA in these patients might lead to underdiagnosing narcolepsy. This research investigates the prevalence and potential causality between OSA and paediatric narcolepsy.

METHODS

A case-control study coupled with a two-sample Mendelian randomization (MR) analysis was employed to explore the prevalence and causal link between paediatric narcolepsy and OSA risk.

RESULTS

The case-control study revealed that paediatric narcolepsy patients are at an increased risk of OSA, with an Odds ratio (OR) of 4.87 (95% CI: 2.20-10.71; P < 0.001). The inverse-variance weighted (IVW) model further suggests a potential causal link between narcolepsy and OSA (IVW OR: 4.671, 95% CI: 1.925-11.290; P < 0.001). Additionally, sensitivity analysis confirmed these findings' reliability.

CONCLUSION

The findings highlight an elevated prevalence and genetic susceptibility to OSA among paediatric narcolepsy patients, underscoring the necessity for clinical screening of OSA. Continued research is essential to clarify the pathogenic mechanisms and develop potential treatments.

Potential Role of Sleep Disturbance in the Development of Early Puberty: Past Clinical Evidence for Future Management

The incidence of early puberty in children has been increasing. It has been suspected that both genetic and various environmental factors such as nutrition and hormonal exposure could influence the mechanisms underlying the earlier onset of puberty. Interestingly, several previous studies have reported a strong connection between sleep and puberty. Specifically, it was discovered that luteinizing hormone (LH), a potential marker for the onset of puberty, was increased during the deep sleep period. Furthermore, a high prevalence of early puberty was observed in patients with sleep disorders, especially in those experiencing narcolepsy. In this review article, findings related to the association between sleep disturbance and early puberty have been comprehensively summarized. Any contrary findings are also included and discussed. Advances in the knowledge surrounding sleep disturbance have led to a greater understanding of a correlation between early puberty and sleep disorder and provide alternative therapeutic options for the treatment of central precocious puberty in the future.

Exploring the association between hypocretin-1 levels and bone mineral content in patients with narcolepsy: A cross-sectional study

INTRODUCTION

Recent studies suggest the existence of a physiologic basis for bone rarefaction and increased risk for fractures. This study aimed to address anthropometric differences between patients with narcolepsy type 1 (NT1) and type 2 (NT2) and discrepancies in bone mineral content (BMC) as a function of hypocretin-1 (Hcrt-1) measured in cerebrospinal fluid (CSF).

METHODS

We have evaluated 31 adult patients (aged 18-65 years) with NT1 and 18 patients with NT2, comparing the groups in terms of anthropometric variables - body mass index (BMI) and waist-to-hip ratio (WHR) - and percentage of bone mineral content (%BMC), measured by bioelectrical impedance analysis (BIA). Statistical analysis assessed the effects of Hcrt-1 levels on CSF, dietary intake, and medication use over these variables. Statistical significance was achieved with a confidence interval of 95 % and p < 0.05.

RESULTS

Patients with NT1 presented with higher BMI (32.04 ± 6.95 vs. 25.38 ± 4.26 kg/m2; p < 0.01) and WHR (0.89 ± 0.09 vs. 0.83 ± 0.09; p = 0.02) compared to NT2, in detriment of %BMC, which was lower for NT1 (4.1 ± 1.02 vs. 4.89 ± 0.59; p < 0.01). Hcrt-1 in CSF showed a positive correlation with %BMC (r = +0.48, p < 0.01) and a negative correlation with anthropometric features (BMI: r = -0.54, p < 0.01; WHR: r = -0.37, p = 0.01). There was a correlation between WHR and diary caloric intake (r = +0.42, p < 0.01).

CONCLUSION

The evaluation of patients with narcolepsy presupposes a syndromic approach comprising symptoms that go far beyond excessive daytime sleepiness. The integrated follow-up, including nutritional profile and anthropometric features, should add value in reducing morbidity in this population.

Cardiovascular Risks in People With Narcolepsy: Expert Panel Consensus Recommendations

BACKGROUND

Observational and retrospective studies suggest that people with narcolepsy may have an increased prevalence of cardiovascular and cardiometabolic comorbidities and may be at greater risk for future cardiovascular events. An expert consensus panel was formed to establish agreement on the risk of hypertension and cardiovascular/cardiometabolic disease in people with narcolepsy and to develop strategies to mitigate these risks.

METHODS AND RESULTS

Experts in sleep medicine and cardiology were selected to participate in the panel. After reviewing the relevant literature, the experts identified key elements, drafted recommendation statements, and developed discussion points to provide supporting evidence for the recommendations. The draft and final recommendations were rated on a scale from 0 (not at all agree) to 4 (very much agree). All experts had an agreement rating of 4.0 for all 14 revised recommendation statements for patients with narcolepsy. These statements comprised 3 themes: (1) recognize the risk of hypertension and cardiovascular/cardiometabolic disease, (2) reduce the risk of hypertension and cardiovascular/cardiometabolic disease, and (3) reduce sodium intake to lower the risk of hypertension and cardiovascular disease.

CONCLUSIONS

These consensus recommendations are intended to increase awareness of potential cardiovascular/cardiometabolic risks in patients with narcolepsy for all clinicians. Early monitoring for, and prevention of, cardiovascular risks in this population are of great importance, especially as narcolepsy usually develops in adolescents and young adults, who will be exposed to adverse effects of the disease for decades. Prospective systematic studies are needed to determine association and causation of narcolepsy with cardiovascular/cardiometabolic disorders.

Narcolepsy and rapid eye movement sleep

Since the first description of narcolepsy at the end of the 19th Century, great progress has been made. The disease is nowadays distinguished as narcolepsy type 1 and type 2. In the 1960s, the discovery of rapid eye movement sleep at sleep onset led to improved understanding of core sleep-related disease symptoms of the disease (excessive daytime sleepiness with early occurrence of rapid eye movement sleep, sleep-related hallucinations, sleep paralysis, rapid eye movement parasomnia), as possible dysregulation of rapid eye movement sleep, and cataplexy resembling an intrusion of rapid eye movement atonia during wake. The relevance of non-sleep-related symptoms, such as obesity, precocious puberty, psychiatric and cardiovascular morbidities, has subsequently been recognized. The diagnostic tools have been improved, but sleep-onset rapid eye movement periods on polysomnography and Multiple Sleep Latency Test remain key criteria. The pathogenic mechanisms of narcolepsy type 1 have been partly elucidated after the discovery of strong HLA class II association and orexin/hypocretin deficiency, a neurotransmitter that is involved in altered rapid eye movement sleep regulation. Conversely, the causes of narcolepsy type 2, where cataplexy and orexin deficiency are absent, remain unknown. Symptomatic medications to treat patients with narcolepsy have been developed, and management has been codified with guidelines, until the recent promising orexin-receptor agonists. The present review retraces the steps of the research on narcolepsy that linked the features of the disease with rapid eye movement sleep abnormality, and those that do not appear associated with rapid eye movement sleep.

Narcolepsy: an interface among neurology, immunology, sleep, and genetics

Narcolepsy is a primary disorder of the central nervous system resulting from genetic, environmental, and immunological interactions defined as excessive daytime sleepiness plus cataplexy, hallucinations, sleep paralysis, and sleep fragmentation. The pathophysiology is not entirely known, but the interaction among genetic predisposition, environmental exposition, and immune component with consequent hypocretin-1 deficiency is the model to explain narcolepsy type I. The mechanism of narcolepsy type II is less understood. There is a delay of over ten years for the diagnosis of narcolepsy around the world. Patients with narcolepsy have many comorbidities with a negative impact on quality of life. The treatment of narcolepsy must contain an educational approach for the family, coworkers, and patients. Scheduled naps and sleep hygiene are essential to minimize the dose of medications. Much progress has been seen in the pharmacological treatment of narcolepsy with new stimulants, different presentations of oxybate, and recent studies with orexin agonists. Narcolepsy is a rare disease that needs to be more understood and highlighted to avoid delayed diagnosis and severe disabilities in patients.

Effect of sodium oxybate on body mass index in pediatric patients with narcolepsy

STUDY OBJECTIVES

We examined body mass index (BMI) changes associated with sodium oxybate treatment (SXB) in pediatric patients with narcolepsy with cataplexy who participated in a double-blind, placebo-controlled, randomized withdrawal study and an open-label continuation period.

METHODS

Participants were aged 7-16 years at screening. SXB-naive participants titrated to twice-nightly dosing of SXB then entered a 2-week stable-dose period; participants taking SXB at study entry entered a 3-week stable-dose period. After a 2-week randomized withdrawal period, all participants entered an open-label safety period (OLP; main study duration: ≤ 52 weeks). Participants who completed the OLP were allowed to enter the open-label continuation period (an additional 1-2 years). BMI percentile categories were defined as underweight (< 5th), normal (5th to < 85th), overweight (≥ 85th to < 95th), and obese (≥ 95th).

RESULTS

Median BMI percentile decreased from baseline to OLP week 52 in SXB-naive participants who were normal weight at baseline (decreased from 77.0 to 35.0) or overweight/obese at baseline (98.0 to 86.7). Median BMI percentile decreased to a lesser extent in participants taking twice-nightly SXB at study entry who were normal weight at baseline (54.6 to 53.0) or overweight/obese at baseline (96.5 to 88.9). Shifts in BMI category from baseline to week 52 were sometimes noted. In SXB-naive participants, 9/10 (90.0%) who were overweight became normal weight, 7/25 (28.0%) who were obese became normal weight, 3/25 (12.0%) who were obese became overweight, and 1/16 (6.3%) who was normal weight became obese. In participants taking SXB at baseline, 5/8 (62.5%) who were overweight became normal weight, 3/6 (50.0%) who were obese became overweight, 1/14 (7.1%) who was normal weight became overweight, and 2/14 (14.3%) who were normal weight became underweight. Median BMI percentiles at months 6 and 12 of the open-label continuation period were similar to those at OLP end (OLP week 52). In SXB-naive participants, the evident BMI z-score decrease over time was relative to the screening values.

CONCLUSIONS

Decreases in BMI percentile and z-score, and downward shifts in BMI category, were observed within 1 year of SXB treatment in pediatric participants with narcolepsy with cataplexy. BMI decreases plateaued after approximately 1 year.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: A Multicenter Study of the Efficacy and Safety of Xyrem With an Open-Label Pharmacokinetic Evaluation and Safety Extension in Pediatric Subjects With Narcolepsy With Cataplexy; URL: https://clinicaltrials.gov/study/NCT02221869; Identifier: NCT02221869.

CITATION

Dauvilliers Y, Lammers GJ, Lecendreux M, et al. Effect of sodium oxybate on body mass index in pediatric patients with narcolepsy. J Clin Sleep Med. 2024;20(3):445-454.

Cardiovascular Burden of Narcolepsy Disease (CV-BOND): a real-world evidence study

STUDY OBJECTIVES

Narcolepsy is associated with cardiovascular risk factors; however, the risk of new-onset cardiovascular events in this population is unknown. This real-world study evaluated the excess risk of new-onset cardiovascular events in U.S. adults with narcolepsy.

METHODS

A retrospective cohort study using IBM MarketScan administrative claims data (2014-2019) was conducted. A narcolepsy cohort, comprising adults (≥18 years) with at least two outpatient claims containing a narcolepsy diagnosis, of which at least one was non-diagnostic, was matched to a non-narcolepsy control cohort (1:3) based on cohort entry date, age, sex, geographic region, and insurance type. The relative risk of new-onset cardiovascular events was estimated using a multivariable Cox proportional hazards model to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

The narcolepsy and matched non-narcolepsy control cohorts included 12 816 and 38 441 individuals, respectively. At baseline, cohort demographics were generally similar; however, patients with narcolepsy had more comorbidities. In adjusted analyses, the risk of new-onset cardiovascular events was higher in the narcolepsy cohort compared with the control cohort: any stroke (HR [95% CI], 1.71 [1.24, 2.34]); heart failure (1.35 [1.03, 1.76]); ischemic stroke (1.67 [1.19, 2.34]); major adverse cardiac event (1.45 [1.20, 1.74]); grouped instances of stroke, atrial fibrillation, or edema (1.48 [1.25, 1.74]); and cardiovascular disease (1.30 [1.08, 1.56]).

CONCLUSION

Individuals with narcolepsy are at increased risk of new-onset cardiovascular events compared with individuals without narcolepsy. Physicians should consider cardiovascular risk in patients with narcolepsy when weighing treatment options.

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.

Long-Term Treatment of Narcolepsy and Idiopathic Hypersomnia with Low-Sodium Oxybate

Narcolepsy and idiopathic hypersomnia are chronic conditions that negatively affect alertness, mental and physical energy, functioning, and quality of life (QoL). Calcium, magnesium, potassium, and sodium oxybates (low-sodium oxybate; LXB) is an oxybate formulation with 92% less sodium than sodium oxybate (SXB; a treatment for narcolepsy) and the same active moiety. LXB is approved in the US for treatment of cataplexy or excessive daytime sleepiness (EDS) in patients 7 years of age or older with narcolepsy, and idiopathic hypersomnia in adults. In Phase 3 clinical trials, LXB exhibited a safety profile consistent with that of SXB in narcolepsy. Besides continued efficacy in treating symptoms, potential benefits of long-term LXB treatment include flexible optimization of dosing and regimen, improvement of QoL and functioning, weight loss, and (relative to SXB in narcolepsy) health benefits of reduced sodium content. Dosing of LXB is twice nightly (for narcolepsy) or once or twice nightly (for idiopathic hypersomnia) based on patient characteristics and response, and individualized titration can be leveraged over the long term as a patient's life circumstances change. Patients with narcolepsy transitioning from SXB initiate LXB at the same dose, and most patients require no further changes to achieve similar efficacy and tolerability. Improvements in functioning and QoL with LXB treatment could have cascading positive effects in multiple domains, particularly in younger patients. In clinical trials, LXB was associated with weight loss in both narcolepsy (in which obesity is a well-established comorbidity) and idiopathic hypersomnia, only occasionally leading participants to be underweight. As both narcolepsy and idiopathic hypersomnia are associated with increased risk of cardiometabolic and cardiovascular comorbidities, limiting medication-related sodium intake with LXB may have significant health benefits, although this has not yet been verified prospectively due to the prolonged follow-up required. LXB is a promising long-term treatment for narcolepsy and idiopathic hypersomnia.

Blood Lymphocyte Subsets and Proinflammatory Cytokine Profile in ROHHAD(NET) and non-ROHHAD(NET) Obese Individuals

Context

Rapid-onset obesity with central hypoventilation, hypothalamic dysfunction, and autonomic dysregulation with neural crest tumors (ROHHAD-NET) syndrome pathophysiology remains elusive. Acquired neuroimmunological dysfunction has been proposed as a possible pathogenetic pathway.

Objective

The aim of our study was to characterize lymphocyte subpopulations subsets in peripheral blood (PB) and to evaluate a panel of proinflammatory cytokines/chemokines in ROHHAD(NET) patients vs controls.

Methods

We included 11 ROHHAD(NET) patients, 7 ROHHAD and 4 ROHHAD-NET, selected by clinical criteria. Controls were 11 simple obese children, matched for age and sex. Flow cytometric analysis and enzyme-linked immunosorbent assay were performed on PB and serum samples of the 2 groups.

Results

Analysis revealed that T lymphocytes are significantly increased in ROHHAD(NET) patients (P = .04) with a prevalence of CD4-T cells (P = .03) and a lower number of activated CD8-T cells (P = .02). With regard to regulatory subset, patients displayed increased regulatory B cells (P = .05) and type-1 regulatory T cells (P = .03). With regard to CD8-T cells, a lower number of T effector memory was observed (P = .02). In contrast, among CD4-T cells, we found a higher number of T naive (P = .04) and T effector (P = .0008). Interleukin-8 (IL-8) levels and monocyte chemotactic protein-1 were increased in patients vs controls (P = .008 and P = .01, respectively). Furthermore, IL-8 levels were higher in the subgroup with neural tumor (P = .0058) (ROHHAD-NET) than in patients without neural tumor (ROHHAD). Soluble HLA-G was significantly lower in patients vs controls (P = .03).

Conclusion

Our findings contribute to support the hypothesis of immune dysregulation, which may underlie this complex, often fatal disease. Because ROHHAD(NET) syndrome is an ultra-rare disease, multicentric studies are needed to improve the effect of our data in the management of this condition.

Sleep Disorders in Childhood

OBJECTIVE

This article provides a comprehensive review of pediatric sleep disorders including the clinical features, diagnosis, and treatment of sleep-disordered breathing, insomnia, parasomnias, restless sleep disorder, restless legs syndrome, narcolepsy in childhood, and Kleine-Levin syndrome.

LATEST DEVELOPMENTS

Our understanding of pediatric sleep pathophysiology continues to evolve, and diagnostic and treatment modalities have expanded. A low-sodium oxybate formulation was approved in July 2020 in the United States to treat cataplexy and excessive daytime sleepiness in patients 7 years old and older with narcolepsy. A validated pediatric hypersomnolence survey for pediatric narcolepsy and idiopathic hypersomnia with high sensitivity, specificity, and interrater reliability is now available.

ESSENTIAL POINTS

The clinical presentation, diagnostics, and treatment of children with sleep disorders differ from those of adults. Untreated sleep disorders in childhood can lead to adverse physical and psychological consequences in adults. Correctly diagnosing and treating sleep disorders in youth can prevent a significant burden of disease in adulthood.

A State-of-Art Review of the Vicious Circle of Sleep Disorders, Diabetes and Neurodegeneration Involving Metabolism and Microbiota Alterations

In the context of neurodegenerative disorders, cognitive decline is frequently reported in older population. Recently, numerous metabolic pathways have been implicated in neurodegeneration, including signaling disruption of insulin and other glucose-regulating hormones. In fact, Alzheimer's disease has now been considered as "type-3 diabetes". In this review, we tried to clarify the role of sleep impairment as the third major player in the complex relationship between metabolic and neurodegenerative diseases. Altered sleep may trigger or perpetuate these vicious mechanisms, leading to the development of both dementia and type 2 diabetes mellitus. Finally, we analyzed these reciprocal interactions considering the emerging role of the gut microbiota in modulating the same processes. Conditions of dysbiosis have been linked to circadian rhythm disruption, metabolic alterations, and release of neurotoxic products, all contributing to neurodegeneration. In a future prospective, gut microbiota could provide a major contribution in explaining the tangled relationship between sleep disorders, dementia and diabetes.

Auxological and endocrine findings in narcolepsy type 1: seventeen-year follow-up from a pediatric endocrinology center

Introduction

Narcolepsy Type 1 (NT1) is a rare hypersomnia of central origin linked to hypocretin deficiency, most frequently arising at pediatric age. NT1 could be associated with endocrine comorbidities involving the neuroendocrine axis, predominantly obesity, and Central Precocious Puberty (CPP). The primary aim of this study is the evaluation of endocrine and auxological parameters at diagnosis and during follow-up in patients with NT1, treated with Sodium Oxybate (SO) or not.

Methods

We retrospectively evaluated the auxological, biochemical, and radiological parameters of 112 patients referred to our Center between 2004-2022. The design of our study is cross-sectional at the time of diagnosis followed by a longitudinal follow-up.

Results

Our study confirms an increased frequency of CPP and obesity in patients with NT1. At first evaluation, obesity was found in 31.3% of patients, while overweight was found in 25.0%. A diagnosis of CPP was made in 19.6% of patients. Interestingly, this group showed a significantly lower level of CSF-hypocretin (hrct-1) at diagnosis compared to others. We found an improvement in BMI SDS in the SO-treated group compared to untreated patients, and this trend persisted also at 36 months of follow-up (0.0 ± 1.3 vs 1.3 ± 0.4; p<0.03). Sixty-three patients reached their final height, with a median SDS of 0.6 ± 1.1 in boys and 0.2 ± 1.2 in girls.

Discussion

To our knowledge, these are the first results regarding the final height in a large series of pediatric patients with NT1, with a normal range of IGF1-SDS levels and stature SDS.

Narcolepsy and Idiopathic Hypersomnia

Narcolepsy types 1 and 2 and idiopathic hypersomnia are primary Central Nervous System (CNS) disorders of hypersomnolence characterized by profound daytime sleepiness and/or excessive sleep need. Onset of symptoms begins typically in childhood or adolescence, and children can have unique presentations compared with adults. Narcolepsy type 1 is likely caused by immune-mediated loss of orexin (hypocretin) neurons in the hypothalamus; however, the causes of narcolepsy type 2 and idiopathic hypersomnia are unknown. Existing treatments improve daytime sleepiness and cataplexy but there is no cure for these disorders.

Resilience and its correlates in patients with narcolepsy type 1

STUDY OBJECTIVES

This study aimed to explore resilience and its possible association with sociodemographic and clinical features in patients with narcolepsy type 1 (NT1).

METHODS

This was a cross-sectional study involving patients with NT1 and age-/sex-matched controls (comparison group). Sociodemographic and clinical data were collected through semistructured interviews and validated questionnaires, including the Epworth Sleepiness Scale (ESS), State-Trait Anxiety Inventory (STAI)-State Anxiety, Beck Depression Inventory (BDI), 36-item Short Form Survey (SF-36), and the Resilience Scale (RS). Different statistical approaches were used to investigate the relationship between resilience and NT1 and associations with sociodemographic and clinical features.

RESULTS

The participants comprised 137 patients (mean age, 38.0 years; 52.6% female) and 149 controls (39.6 years; 55.7% female). Compared with controls, patients had a significantly lower (122.6 vs 135.5) mean RS score and a 2-fold risk of having low/mild-range resilience (adjusted odds ratio = 1.99, 95% confidence interval 1.13-3.52). Patients with high resilience had sociodemographic and narcolepsy characteristics similar to patients with low resilience, but they reported anxiety and depressive symptomatology less frequently (4.2% vs 55.8% and 58.3%, respectively), and their SF-36 scores were comparable to those of the comparison group. In patients, RS score was strongly associated with STAI-State Anxiety and BDI (rho = -0.57 and -0.56, respectively) and weakly with ESS (rho = -20) scores.

CONCLUSIONS

The results of this study suggest that resilience may play a key role in patients' adaptation to NT1. Furthermore, this study supports interventions aimed at increasing patients' resilience and provides a base for further studies, preferably longitudinal and including objective measures, directed toward understanding the relationship between resilience, depression, and quality of life in patients with narcolepsy.

CITATION

D'Alterio A, Menchetti M, Zenesini C, et al. Resilience and its correlates in patients with narcolepsy type 1. J Clin Sleep Med. 2023;19(4):719-726.

Real-world treatment of pediatric narcolepsy with pitolisant: A retrospective, multicenter study

BACKGROUND

First symptoms of narcolepsy mostly present during childhood. Pharmacological management options in children are limited, also due to approval status. Pitolisant is an inverse histamine 3 receptor agonist and has been approved for the treatment of adult narcolepsy with or without cataplexy by EMA and FDA. Clinical experience indicates for a beneficial use also in children and adolescents. Our goal was to evaluate the effects and tolerability of pitolisant in narcolepsy children/adolescents in a real-world setting.

METHODS

This multicentre retrospective observational study included 55 patients with narcolepsy from three international narcolepsy centers (Germany, France and Italy) who were treated with pitolisant. Patients were eligible if they were at least 6 years old and diagnosed with narcolepsy type 1 or 2. Demographic and clinical characteristics, questionnaires, sleep medicine and laboratory data were collected.

RESULTS

55 children/adolescents (25 girls, 45.45%, 30 boys, 54.55%) aged 6-18 years, with narcolepsy (type 1 = 92.7%, type 2 = 7.3%), were treated with pitolisant. The mean pitolisant dose was 34.1 mg/d. Treatment was effective for excessive daytime sleepiness (EDS) and cataplexy: the pediatric Epworth Sleepiness Scale (ESS) score decreased from 19 to 13.5 (p < 0.001) and the weekly cataplexy frequency improved from 7.9 at baseline to 5.2 (p < 0.001). Treatment with pitolisant was well tolerated. Side effects were mild and mostly short-term. Insomnia was reported most frequently (5.5%).

CONCLUSION

First real-world results suggest that pitolisant treatment is effective in improving EDS and cataplexy in children with narcolepsy, and also is well tolerated.

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.

What, when and by whom? Adolescents' and parents' preferences concerning narcolepsy information

OBJECTIVE

To investigate adolescents' and parents' preferences concerning information on narcolepsy.

METHODS

During a one-year cross-sectional study, adolescents (12-20 years old) with narcolepsy and parents attending the Narcolepsy Center of Bologna (Italy) were invited to fill in a questionnaire including 28 pieces of information regarding narcolepsy, 14 concerning medical issues (i.e., diagnosis, prognosis, treatment, management) and 14 concerning psychosocial issues (i.e., impact on everyday life, relationships, possible support). Participants were asked to indicate: the importance of each item on a 5-point Likert scale; when each piece of information should be provided (diagnostic suspicion, confirmed diagnosis, follow-up visits, upon patient's request); and who should provide it (doctor, nurse, psychologist, parents and/or others).

RESULTS

Sixty-two adolescents (37% female, mean age 16.4 years) and 96 parents (58% female, mean age 48.2 years) agreed to participate (100% response rate). Parents rated all items as important (score≥4), while, according to adolescents, 11/14 medical and psychosocial issues were important. The moment of diagnosis was considered the right time to give almost all medical information. Regarding psychosocial issues, mothers mainly indicated the time of diagnosis, while fathers also indicated follow-up visits, and some children opted for follow-up visits or information upon request. The doctor was the preferred provider but when information concerned psychosocial issues, adolescents also indicated the parents, and parents also indicated the psychologist.

CONCLUSIONS

This study suggests that information on narcolepsy should be comprehensive and tailored, and that parents and psychologists may support the doctor in providing information when narcolepsy is diagnosed during adolescence.

Progress of autonomic disturbances in narcolepsy type 1

Narcolepsy type 1 is a kind of sleep disorder characterized by a specific loss of hypocretin neurons in the lateral hypothalamus and reduced levels of hypocretin-1 in the cerebrospinal fluid. Hypocretin deficiency is associated with autonomic disorders. This article summarizes the autonomic disorders and possible mechanisms associated with narcolepsy type 1. Patients with narcolepsy type 1 often have various systemic autonomic symptoms, including non-dipping blood pressure, reduced heart rate variability, dynamic cerebral autoregulation impairment, reduced gastric motility and emptying, sleep-related erectile dysfunction, skin temperature abnormalities, and blunted pupillary light reflex. Similar findings should strengthen the recognition and intervention of these disturbances in clinical practice. In addition to hypocretin deficiency, current evidence also indicates that pharmacological therapy (including psychostimulants and anti-cataplectic drugs) and comorbidities may contribute to the alterations of autonomic system observed in narcolepsy type 1.

Body Weight and Metabolic Rate Changes in Narcolepsy: Current Knowledge and Future Directions

Narcolepsy is a known auto-immune disease that presents mainly in the teenage years with irresistible sleep attacks. Patients with narcolepsy, especially NT1, have been found to have a high prevalence of obesity and other metabolic derangements. This narrative review aimed to address the relationship between narcolepsy and changes in weight and metabolic rate, and discuss potential mechanisms for weight gain and metabolic changes and future research agendas on this topic. This article will provide a balanced, up-to-date critical review of the current literature, and delineate areas for future research, in order to understand the pathophysiological metabolic changes in narcolepsy. Articles using predefined keywords were searched for in PubMed and Google Scholar databases, with predefined inclusion and exclusion criteria. Compared to controls, patients with narcolepsy are more likely to be obese and have higher BMIs and waist circumferences. According to recent research, weight gain in narcolepsy patients may be higher during the disease's outset. The precise mechanisms causing this weight gain remains unknown. The available information, albeit limited, does not support differences in basal or resting metabolic rates between patients with narcolepsy and controls, other than during the time of disease onset. The evidence supporting the role of orexin in weight gain in humans with narcolepsy is still controversial, in the literature. Furthermore, the available data did not show any appreciable alterations in the levels of CSF melanin-concentrating hormone, plasma and CSF leptin, or serum growth hormone, in relation to weight gain. Other mechanisms have been proposed, including a reduction in sympathetic tone, hormonal changes, changes in eating behavior and physical activity, and genetic predisposition. The association between increased body mass index and narcolepsy is well-recognized; however, the relationship between narcolepsy and other metabolic measures, such as body fat/muscle distribution and metabolic rate independent of BMI, is not well documented, and the available evidence is inconsistent. Future longitudinal studies with larger sample sizes are needed to assess BMR in patients with narcolepsy under a standard protocol at the outset of narcolepsy, with regular follow-up.

Precocious puberty in narcolepsy type 1: Orexin loss and/or neuroinflammation, which is to blame?

Narcolepsy type 1 (NT1) is a rare neurological sleep disorder triggered by postnatal loss of the orexin/hypocretin neuropeptides. Overweight/obesity and precocious puberty are highly prevalent comorbidities of NT1, with a close temporal correlation with disease onset, suggesting a common origin. However, the underlying mechanisms remain unknown and merit further investigation. The main question we address in this review is whether the occurrence of precocious puberty in NT1 is due to the lack of orexin/hypocretin or rather to a wider hypothalamic dysfunction in the context of neuroinflammation, which is likely to accompany the disease given its autoimmune origins. Our analysis suggests that the suspected generalized neuroinflammation of the hypothalamus in NT1 would tend to delay puberty rather than hastening it. In contrast, that the brutal loss of orexin/hypocretin would favor an early reactivation of gonadotropin-releasing hormone (GnRH) secretion during the prepubertal period in vulnerable children, leading to early puberty onset. Orexin/hypocretin replacement could thus be envisaged as a potential treatment for precocious puberty in NT1. Additionally, we put forward an alternative hypothesis regarding the concomitant occurrence of sleepiness, weight gain and early puberty in NT1.

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.

Characterization of rapid weight gain phenotype in children with narcolepsy

OBJECTIVES

To characterize the rapid weight gain (RWG) phenotype associated with the onset of childhood narcolepsy and to determine whether it could constitute a marker of severity of the disease.

METHODS

RWG was defined using the BMI z-score slope reported to one year (>0.67 SD) from symptom onset to disease diagnosis. We compared the clinical, metabolic, and sleep characteristics between patients with or without RWG at diagnosis. Pharmacological management, anthropometric, and clinical progression were also evaluated during the follow-up.

RESULTS

A total of 84 de novo narcoleptic pediatric patients were included; their median age at diagnosis was 12.0 years; 59.5% boys, 90.5% cataplexy, and 98.7% HLA-DQB1*06:02, 57% had RWG profile. RWG patients were younger at diagnosis than non-RWG patients, despite a shorter diagnostic delay. They had a higher BMI z-score and a higher prevalence of obesity at diagnosis, but not at symptom onset, and higher adapted Epworth Sleepiness Scale and Insomnia Severity Index scores than non-RWG patients. No differences on nocturnal polysomnography and multiple sleep latency tests were found between groups at disease diagnosis. After a median follow-up of 5 years, RWG patients still had a higher BMI z-score and a higher prevalence of obesity despite benefiting from the same therapeutic management and displaying improvement in sleepiness and school difficulties.

CONCLUSIONS

Narcoleptic RWG patients were younger, sleepier, and the prevalence of obesity was higher at diagnosis despite a shorter diagnostic delay than that of non-RWG patients. These patients had also a higher risk of developing a long-term obesity, despite a positive progression of their narcoleptic symptoms. RGW could then represent a maker of a more severe phenotype of childhood narcolepsy, which should inspire a prompt and more offensive management to prevent obesity and its complications.

Narcolepsy: a model interaction between immune system, nervous system, and sleep-wake regulation

Narcolepsy is a rare chronic neurological disorder characterized by an irresistible excessive daytime sleepiness and cataplexy. The disease is considered to be the result of the selective disruption of neuronal cells in the lateral hypothalamus expressing the neuropeptide hypocretin, which controls the sleep-wake cycle. Diagnosis and management of narcolepsy represent still a substantial medical challenge due to the large heterogeneity in the clinical manifestation of the disease as well as to the lack of understanding of the underlying pathophysiological mechanisms. However, significant advances have been made in the last years, thus opening new perspective in the field. This review describes the current knowledge of clinical presentation and pathology of narcolepsy as well as the existing diagnostic criteria and therapeutic intervention for the disease management. Recent evidence on the potential immune-mediated mechanisms that may underpin the disease establishment and progression are also highlighted.

Finnish children who experienced narcolepsy after receiving the Pandemrix vaccine during the 2009-2010 H1N1 pandemic demonstrated high level of psychosocial problems

AIM

We assessed psychosocial burdens in children who developed narcolepsy after receiving the Pandemrix H1N1 vaccine during the 2009-2010 pandemic. Parental quality of life was also assessed.

METHODS

This multicentre study covered four of the five Finnish University Hospital Districts, which dealt with about 90% of the paediatric narcolepsy cases after the Pandemrix vaccination. The medical records of children diagnosed from 2010 to 2014 were reviewed. The questionnaires included the Youth Self-Report (YSR), Children's Depression Inventory (CDI), the Child Behaviour Checklist (CBCL) and questions on parental resources, stress and quality of life.

RESULTS

We obtained the medical records of 94 children who were aged 5-17 years at the time of their narcolepsy diagnosis and questionnaire data for 73 of those children. Most children had strong narcolepsy symptoms, and 25% had CDI scores that suggested depression. In addition, 41% had total CBCL problem scores above the clinically significant limit and 48% were anxious, withdrawn and had somatic complaints. Sleep latency was weakly associated with the CBCL total problem score. Half of the children needed psychiatric interventions and parental stress was common.

CONCLUSION

Depression and behavioural problems were common in children with narcolepsy after the Pandemrix vaccination and their parents frequently reported feeling stressed.

The role of mtDNA haplogroups on metabolic features in narcolepsy type 1

Narcolepsy type 1 (NT1) is due to selective loss of hypocretin (hcrt)-producing-neurons. Hcrt is a neuropeptide regulating the sleep/wake cycle, as well as feeding behavior. A subset of NT1 patients become overweight/obese, with a dysmetabolic phenotype. We hypothesized that mitochondrial DNA (mtDNA) sequence variation might contribute to the metabolic features in NT1 and we undertook an exploratory survey of mtDNA haplogroups in a cohort of well-characterized patients. We studied 246 NT1 Italian patients, fully defined for their metabolic features, including obesity, hypertension, low HDL, hypertriglyceridemia and hyperglycemia. For haplogroup assignment, the mtDNA control region was sequenced in combination with an assessment of diagnostic markers in the coding region. NT1 patients displayed the same mtDNA haplogroups (H, HV, J, K, T, U) frequency as those reported in the general Italian population. The majority of NT1 patients (64%) were overweight: amongst these, 35% were obese, 48% had low HDL cholesterol levels, and 31% had hypertriglyceridemia. We identified an association between haplogroups J, K and hypertriglyceridemia (P=0.03, 61.5% and 61.5%, respectively vs. 31.3% of the whole sample) and after correction for age and sex, we observed a reduction of these associations (OR=3.65, 95%CI=0.76-17.5, p=0.106 and 1.73, 0.52-5.69, p=0.368, respectively). The low HDL level showed a trend for association with haplogroup J (P=0.09, 83.3% vs. 47.4% of the whole sample) and after correction we observed an OR=6.73, 95%CI=0.65-69.9, p=0.110. Our study provides the first indication that mtDNA haplogroups J and K can modulate metabolic features of NT1 patients, linking mtDNA variation to the dysmetabolic phenotype in NT1.

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.

Metabolomic Signature of Patients With Narcolepsy

BACKGROUND AND OBJECTIVE

Narcolepsy type 1 (NT1) is an orphan brain disorder caused by the irreversible destruction of orexin neurons. Metabolic disturbances are common in patients with NT1 who have a body mass index (BMI) 10-20% higher than the general population, with one third being obese (BMI>30 kg/m²). Besides the destruction of orexin neurons in NT1, the metabolic alterations in obese and non-obese patients with narcolepsy type 1 remain unknown. The aim of the study was to identify possible differences in plasma metabolic profiles between patients with NT1 and controls as a function of their BMI status.

METHODS

We used a targeted liquid chromatography-mass spectrometry metabolomics approach to measure 141 circulating, low molecular weight metabolites in drug-free fasted plasma samples from 117 NT1 patients (including 41 obese subjects) compared with 116 BMI-matched controls (including 57 obese subjects).

RESULTS

Common metabolites driving the difference between NT1 and controls, irrespective of BMI, were identified, namely sarcosine, glutamate, nonaylcarnitine (C9), 5 long chain lysophosphatidylcholine acyls, one sphingolipid, 12 phosphatidylcholine diacyls and 11 phosphatidylcholine acyl-akyls, all showing increased concentrations in NT1. Metabolite concentrations significantly affected by NT1 (n = 42) and BMI category (n = 40) showed little overlap (n = 5). Quantitative enrichment analysis revealed common metabolic pathways that were implicated in the NT1/control differences, in both normal BMI and obese comparisons, namely glycine and serine, arachidonic acid, and tryptophan metabolisms. The metabolites driving these differences were glutamate, sarcosine and ornithine (glycine and serine metabolism), glutamate and PC aa C34:4 (arachidonic acid metabolism) and glutamate, serotonin and tryptophan (tryptophan metabolism). Linear metabolite-endophenotype regression analyses highlight that as part of the NT1 metabolic phenotype, most of the relationships between the sleep parameters (i.e. slow wave sleep duration, sleep latency and periodic leg movement) and metabolite concentrations seen in the controls were lost.

DISCUSSION

These results represented the most comprehensive metabolic profiling of patients with NT1 as a function of BMI and propose some metabolic diagnostic biomarkers for NT1, namely glutamate, sarcosine, serotonin, tryptophan, nonaylcarnitine and some phosphatidylcholines. The metabolic pathways identified offer, if confirmed, possible targets for treatment of obesity in NT1.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that a distinct metabolic profile can differentiate patients with Narcolepsy Type 1 from patients without the disorder.

The Genetics of Sleep Disorders in Children: A Narrative Review

Sleep is a universal, highly preserved process, essential for human and animal life, whose complete functions are yet to be unravelled. Familial recurrence is acknowledged for some sleep disorders, but definite data are lacking for many of them. Genetic studies on sleep disorders have progressed from twin and family studies to candidate gene approaches to culminate in genome-wide association studies (GWAS). Several works disclosed that sleep-wake characteristics, in addition to electroencephalographic (EEG) sleep patterns, have a certain degree of heritability. Notwithstanding, it is rare for sleep disorders to be attributed to single gene defects because of the complexity of the brain network/pathways involved. Besides, the advancing insights in epigenetic gene-environment interactions add further complexity to understanding the genetic control of sleep and its disorders. This narrative review explores the current genetic knowledge in sleep disorders in children, following the International Classification of Sleep Disorders-Third Edition (ICSD-3) categorisation.

BMI changes in pediatric type 1 narcolepsy under sodium oxybate treatment

Pediatric type 1 narcolepsy (NT1) is often associated with overweight and obesity. Sodium oxybate (SO), approved for the treatment of narcolepsy with cataplexy from the age of 7 years old in the United States, has been associated with weight loss, although longitudinal pediatric studies are lacking. We report a retrospective cohort of 129 consecutive patients with a 4-year follow-up, to analyze the impact of different pharmacological treatments on body mass index (BMI) z-score. At baseline, the prevalence of obesity and overweight was 26.4% (34/129) and 29.5% (38/129), respectively. Patients were divided into three groups: children treated with SO alone (group 1), with SO-combined therapy (group 2), and without SO (group 3). At the end of the first year of follow-up, group 1 and group 2 showed a significant BMI z-score reduction compared to baseline: from 1.2 ± 1.1 to 0.4 ± 1.4 for group 1 (p < 0.001), and from 1.4 ± 1.1 to 1 ± 1.3 for group 2 (p = 0.002), independently from baseline clinical features. In the second year, only group 2 experienced a further and significant BMI z-score decrease (from 1.0 ± 1.2 to 0.6 ± 1.2, p = 0.037). No further significant BMI z-score changes were observed in SO-treated patients in the following years. Instead, children treated without SO developed a significant weight increase between the second and third year of therapy (BMI z-score from 0.3 ± 0.9 to 0.5 ± 0.9). In conclusion, SO treatment in pediatric NT1 is associated with a favorable weight reduction in the first year of treatment.

Endocrine and metabolic aspects of narcolepsy type 1 in children

STUDY OBJECTIVES

To study whether the onset of narcolepsy type 1 (NT1) in children and adolescents affects BMI, specific metabolic risk factors, the onset of puberty, longitudinal growth or other endocrine functions.

METHODS

A population-based study, comprising 34 patients, was performed with a clinical evaluation, an assessment of puberty and growth, actigraphy and blood samples at fasting, from patients and controls, to evaluate pituitary function, growth factors, thyroid gland, gonads, insulin sensitivity, appetite regulation and blood lipids.

RESULTS

In the post-H1N1 vaccination (PHV) narcolepsy group, the median BMI SDS was higher 6-12 months after the onset of narcolepsy (p < 0.01), but it was no different 10 years after the onset of narcolepsy (p = 0.91), compared with 12-24 months before the onset of narcolepsy. There was a correlation between an increase in BMI and a decrease in total energy expenditure (R = -0.74). In the nPHV group, weight and BMI changes were smaller and no significant changes were recorded. Early puberty was more common in patients with puberty onset after narcolepsy onset (n = 16/19) compared with patients with puberty onset before narcolepsy onset (n = 3/11, p = 0.02). There was no significant change in height SDS during the studied period. Although they were within normal ranges, both median HDL and median TSH levels were significantly lower in NT1 patients, compared with controls.

CONCLUSIONS

We found a high prevalence of large BMI gain in the period immediately after the onset of narcolepsy, which had almost normalized at the long-term follow-up. The onset of narcolepsy led to early puberty in both sexes. Linear growth was not affected. We did not find any strong indicators of metabolic disturbances.

Narcolepsy type 1 features across the life span: age impact on clinical and polysomnographic phenotype

STUDY OBJECTIVES

Narcolepsy type 1 (NT1) is a chronic neurological disorder typically arising during adolescence and young adulthood. Recent studies demonstrated that NT1 presents with age-specific features, especially in children. With this study we aimed to describe and to compare the clinical pictures of NT1 in different age groups.

METHODS

In this cross-sectional, multicenter study, 106 untreated patients with NT1 enrolled at the time of diagnosis underwent clinical evaluation, a semistructured interview (including the Epworth Sleepiness Scale), nocturnal video-polysomnography, and the Multiple Sleep Latency Test. Patients were enrolled in order to establish 5 age-balanced groups (childhood, adolescence, adulthood, middle age, and senior).

RESULTS

The Epworth Sleepiness Scale score showed a significant increase with age, while self-reported diurnal total sleep time was lower in older and young adults, with the latter also complaining of automatic behaviors in more than 90% of patients. Children reported the cataplexy attacks to be more frequent (> 1/d in 95% of patients). "Recalling an emotional event," "meeting someone unexpectedly," "stress," and "anger" were more frequently reported in adult and older adult patients as possible triggers of cataplexy. Neurophysiological data showed a higher number of sleep-onset rapid eye movement periods on the Multiple Sleep Latency Test in adolescent compared to senior patients and an age-progressive decline in sleep efficiency.

CONCLUSIONS

Daytime sleepiness, cataplexy features and triggers, and nocturnal sleep structure showed age-related difference in patients with NT1; this variability may contribute to diagnostic delay and misdiagnosis.

Sleep and Puberty

In the 1970's, Boyar and colleagues made the seminal observation that during the early stages of puberty, there is a sleep-specific augmentation of pulsatile luteinizing hormone (LH) secretion. Building on this tantalizing association between sleep and the re-awakening of the neuro-reproductive axis, a number of investigators have since mapped the dynamic relationship between sleep and reproductive hormones across the pubertal transition. In this review, we focus on the complex, reciprocal relationship between sleep and reproductive hormones during adolescence as well as the potential effects of melatonin and orexin on gonadotropin-releasing hormone (GnRH) activity in children with chronic insomnia and narcolepsy, respectively. Given the important interaction between the reproductive and somatotropic axes during puberty, we end with a discussion of sleep and growth hormone (GH) secretion in children.

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.

Cardiovascular disorders in narcolepsy: Review of associations and determinants

Narcolepsy type 1 (NT1) is a lifelong disorder of sleep-wake dysregulation defined by clinical symptoms, neurophysiological findings, and low hypocretin levels. Besides a role in sleep, hypocretins are also involved in regulation of heart rate and blood pressure. This literature review examines data on the autonomic effects of hypocretin deficiency and evidence about how narcolepsy is associated with multiple cardiovascular risk factors and comorbidities, including cardiovascular disease. An important impact in NT1 is lack of nocturnal blood pressure dipping, which has been associated with mortality in the general population. Hypertension is also prevalent in NT1. Furthermore, disrupted nighttime sleep and excessive daytime sleepiness, which are characteristic of narcolepsy, may increase cardiovascular risk. Patients with narcolepsy also often present with other comorbidities (eg, obesity, diabetes, depression, other sleep disorders) that may contribute to increased cardiovascular risk. Management of multimorbidity in patients with narcolepsy should include regular assessment of cardiovascular health (including ambulatory blood pressure monitoring), mitigation of cardiovascular risk factors (eg, cessation of smoking and other lifestyle changes, sleep hygiene, and pharmacotherapy), and prescription of a regimen of narcolepsy medications that balances symptomatic benefits with cardiovascular safety.

Recognizing the Symptom Spectrum of Narcolepsy to Improve Timely Diagnosis: A Narrative Review

Narcolepsy is a chronic sleep disorder with a strong negative impact on quality of life, especially when untreated. Diagnostic delay is a persistent problem, with obvious detrimental effects on patients. A diagnosis of narcolepsy may be delayed because of its broad symptom presentation which is much more encompassing than the classical "tetrad" of sleepiness, cataplexy, hallucinations, and sleep paralysis. Furthermore, symptoms can vary over time. Presentation of symptoms can also be markedly different between children and adults. Finally, common sleep-related comorbidities increase the risk of narcolepsy being masked by overlapping symptoms or treatment. In this review, we provide a detailed description of the broad and dynamic symptom spectrum of narcolepsy, with specific attention to the different manifestations in both adults and children. The overarching goal is to help not only sleep specialists, but general practitioners, pediatricians, and other caregivers with early recognition and prompt diagnosis of this severe but treatable disorder.

Dysregulation of the orexin/hypocretin system is not limited to narcolepsy but has far-reaching implications for neurological disorders

Neuropeptides orexin A and B (OX-A/B, also called hypocretin 1 and 2) are released selectively by a population of neurons which projects widely into the entire central nervous system but is localized in a restricted area of the tuberal region of the hypothalamus, caudal to the paraventricular nucleus. The OX system prominently targets brain structures involved in the regulation of wake-sleep state switching, and also orchestrates multiple physiological functions. The degeneration and dysregulation of the OX system promotes narcoleptic phenotypes both in humans and animals. Hence, this review begins with the already proven involvement of OX in narcolepsy, but it mainly discusses the new pre-clinical and clinical insights of the role of OX in three major neurological disorders characterized by sleep impairment which have been recently associated with OX dysfunction, such as Alzheimer's disease, stroke and Prader Willi syndrome, and have been emerged over the past 10 years to be strongly associated with the OX dysfunction and should be more considered in the future. In the light of the impairment of the OX system in these neurological disorders, it is conceivable to speculate that the integrity of the OX system is necessary for a healthy functioning body.

Various causative factors and associated complications of childhood obesity in Jeddah, western region, Saudi Arabia

OBJECTIVE

to investigate the causative factors and complications attributable to obesity in children living in jeddah, saudi arabia.

METHODS

this is a retrospective study encompassing a sample size of 151 children and adolescents between the ages of 4 and 20 years. data was collectived through revieweing medical records, medical files on the hospital electironic system and clinical interviews conducted with legal guardians. date of study was from january to june 2018, and was carried in jeddah, western region, saudi arabia.

RESULTS

data was entered, coded, cleaned and analysed using statistical package for social science (IBM SPSS), version 22. the analysis was done by assessing the significance of various risk factors ands equalae in their contribution to paediatric obesity by one way ANOVA for nominal variables of more than two categories and independent sample t-test for the nominal variables with two categories. the sample was 47% of the male gender whereas females made for the remaining 53%. the causation of obesity was distributed among the following factors: an unhealthy diet, a sedentary lifestyle, medications such as glucocorticoids, and complications attributed to obesity included gastro-oesophageal reflux, hypertension, precocious puberty, sleep apnoea, psychological disturbances and fatty liver diseases.

CONCLUSION

environmental factors were found to be the most predominant cause, where the majority of children were found to be leading a sedentary lifestyle, following an unhealthy diet, and skipping meals. the msot recurring complications involved psychosocial and behavioural abnormalities, and among the medical consequences, gastro-oesophageal reflux and obstructive sleep apnoea were the most prevalent.

Narcolepsy with cataplexy: Does age at diagnosis change the clinical picture?

Objective

To compare symptoms and sleep characteristics in patients diagnosed with narcolepsy‐cataplexy (NC) before and after the age of 18 years.

Methods

De novo patients with NC diagnosis completed a standardized questionnaire and interview, followed by a sleep study. The clinical and sleep measures were compared between patients diagnosed before (46 children, median age: 12 year old) and after (46 adults, median age: 28.5 year old) 18 years of age.

Results

The frequency of obesity (54% vs 17%), night eating (29% vs 7%), parasomnia (89% vs 43%), sleep talking (80% vs 34%), and sleep drunkenness (69% vs 24%) were higher in children than in adults, the frequency of sleep paralysis was lower (20% vs 55%) but the frequency of cataplexy and the severity of sleepiness were not different. Children scored higher than adults at the attention‐deficit/hyperactivity disorder (ADHD) scale. Depressive feelings affected not differently children (24%) and adults (32%). However, adults had lower quality of life than children. There was no difference between groups for insomnia and fatigue scores. Quality of life was essentially impacted by depressive feelings in both children and adults. Obstructive apnea‐hypopnea index (OAHI) was lower in children with higher mean and minimal oxygen saturation than in adults. No between‐group differences were found at the multiple sleep latency test. The body mass index (z‐score) was correlated with OAHI (r = .32).

Conclusion

At time of NC diagnosis, children have more frequent obesity, night eating, parasomnia, sleep talking, drunkenness, and ADHD symptoms than adults, even if sleepiness and cataplexy do not differ. These differences should be considered to ensure a prompt diagnosis.

Associations of plasma hypocretin-1 with metabolic and reproductive health: Two systematic reviews of clinical studies

The hypocretin system consists of two peptides hypocretin-1 and hypocretin-2 (HCRT1 and HCRT2). Hypocretin-containing neurons are located in the posterior and lateral hypothalamus, and have widespread projections throughout the brain and spinal cord. In addition to its presence in the cerebrospinal fluid (CSF), peripheral HCRT1 has been detected in plasma. Robust experimental evidence demonstrates functions of hypothalamic-originated HCRT1 in regulation of multiple biological systems related to sleep-wake states, energy homeostasis and endocrine function. In contrast, HCRT1 studies with human participants are limited by the necessarily invasive assessment of CSF HCRT1 to patients with underlying morbidity. Regulation by HCRT1 of energy homeostasis and reproduction in animals suggests similar regulation in humans and prompts these two systematic reviews. These reviews translate prior experimental findings from animal studies to humans and examine associations between HCRT1 and: 1) metabolic risk factors; 2) reproductive function in men, women and children. A total of 21 studies and six studies met the inclusion criteria for the two searches, respectively. Research question, study design, study population, assessments of HCRT1, reproductive, cardiometabolic data and main findings were extracted. Associations between HCRT1, metabolic and reproductive function are inconsistent. Limitations of studies and future research directions are outlined.

Various causative factors and associated complications of childhood obesity in Jeddah, Western Region, Saudi Arabia

Objective:

The objective of the study was to investigate the causative factors and complications attributable to obesity in children living in Jeddah, Saudi Arabia.

Methods:

This is a retrospective study encompassing a sample size of 151 children and adolescents between the ages of 4 and 20 years. Data were collected through reviewing medical records, medical files on the hospital electronic system, and clinical interviews conducted with legal guardians. The date of the study was from January to June 2018, and the study was carried out in Jeddah, Western Region, Saudi Arabia.

Results:

Data were entered, coded, cleaned, and analyzed using the Statistical Package for the Social Sciences (IBM SPSS), version 22. The analysis was done by assessing the significance of various risk factors and sequelae in their contribution to pediatric obesity by one-way ANOVA for nominal variables of more than two categories and independent-samples t-test for the nominal variables with two categories. The sample was 47% of the male gender, whereas females made for the remaining 53%. The causation of obesity was distributed among the following factors: an unhealthy diet, a sedentary lifestyle, medications such as glucocorticoids, and complications attributed to obesity including gastroesophageal reflux, hypertension, precocious puberty, sleep apnea, psychological disturbances, and fatty liver diseases.

Conclusion:

Environmental factors were found to be the most predominant cause, where the majority of children were found to be leading a sedentary lifestyle, following an unhealthy diet, and skipping meals. The most recurring complications involved psychosocial and behavioral abnormalities, and among the medical consequences, gastroesophageal reflux and obstructive sleep apnea were the most prevalent.

Narcolepsy in Children and Adults: A Guide to Improved Recognition, Diagnosis and Management

Narcolepsy is a rare condition that affects children and adults, and commonly has an onset in childhood. Time to appropriate diagnosis frequently is at least a decade. Unrecognized or misdiagnosed symptoms of narcolepsy contribute to increased morbidity, disability and socioeconomic liability in these patients. Delays in diagnosis may be related to variability in presentation in childhood, lack of familiarity with symptoms or appropriate diagnostic testing or misdiagnosis with accidental introduction of treatment that may modify or mask narcolepsy features. Improved awareness about the diagnosis and tailored therapies improve clinical and socioeconomic outcomes by reducing time to effective treatment. Application of effective treatment results in long-term benefits by improving clinical outcomes, potentially enabling improved education, increased employment opportunity, and improved work productivity and quality of life. This review provides a comprehensive stepwise approach to improve knowledge and comfort for recognition of symptoms, diagnostic strategies and management considerations of narcolepsy in children and adults.

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.