Recognition and management of narcolepsy

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.

Pandemic influenza A H1N1 vaccines and narcolepsy: vaccine safety surveillance in action

The 2009 influenza A H1N1 pandemic placed unprecedented demand on public health authorities and the vaccine industry. Efforts were coordinated internationally to maximise the speed of vaccine development, distribution, and delivery, and the European Union's novel fast-track authorisation procedures mandated increased postmarketing surveillance to monitor vaccine safety. Clinicians in Finland and Sweden later identified an apparent increase in the incidence of narcolepsy associated with a specific adjuvanted pandemic influenza vaccine. After extensive review, the European Medicines Agency confirmed the existence of this association, which has since been detected in England, Ireland, France, and Norway. Assessments of the causal mechanisms continue. In this Review, we discuss how the narcolepsy association was detected, and we present the evidence according to the causality assessment criteria for adverse events following immunisation. The lessons learnt emphasise the central role of alert clinicians in reporting of suspected adverse reactions, and the importance of internationally robust postmarketing surveillance strategies as crucial components in future mass immunisation programmes.

Diagnosis and treatment of sleep disorders: a brief review for clinicians

Sleep disorders encompass a wide spectrum of diseases with significant individual health consequences and high economic costs to society. To facilitate the diagnosis and treatment of sleep disorders, this review provides a framework using the International Classification of Sleep Disorders, Primary and secondary insomnia are differentiated, and pharmacological and nonpharmacological treatments are discussed. Common circadian rhythm disorders are described in conjunction with interventions, including chronotherapy and light therapy. The diagnosis and treatment of restless legs syndrome/periodic limb movement disorder is addressed. Attention is focused on obstructive sleep apnea and upper airway resistance syndrome, and their treatment. The constellation of symptoms and findings in narcolepsy are reviewed together with diagnostic testing and therapy, Parasomnias, including sleep terrors, somnambulism, and rapid eye movement (REM) behavior sleep disorders are described, together with associated laboratory testing results and treatment.

Childhood-onset narcolepsy, obesity and puberty in four consecutive children: a close temporal link

Narcolepsy is a rare but disabling condition that causes excessive daytime sleepiness. Interestingly, weight gain is frequent in patients with narcolepsy and it has sometimes been described very early in the course of the disease. Here, we report four consecutive obese children who were referred to our sleep laboratory for excessive daytime sleepiness and suspected sleep apnoea syndrome. They underwent nocturnal polysomnography associated with multiple sleep latency tests. Narcolepsy was diagnosed in all children with a close temporal link between the onset of narcolepsy, obesity and puberty. Scientifically, the relationship between sleep, weight, growth rate and puberty onset is striking and merits further investigation. From the clinical point of view, narcolepsy must be investigated in obese sleepy children along with obstructive sleep apnoea. Indeed, it can be controlled with appropriate treatment but the proper diagnosis relies not only upon nocturnal polysomnography but involves the systematic use of multiple sleep latency tests.

Treatment with venlafaxine in six cases of children with narcolepsy and with cataplexy and hypnagogic hallucinations

OBJECTIVE

Narcolepsy with cataplexy is a chronic neuropsychiatric disorder associated with inappropriate control of rapid eye movement (REM) sleep. The main symptoms are excessive daytime sleepiness, cataplexy, hypnagogic hallucinations, and disturbed nocturnal sleep. Cataplexy is marked by episodes of muscular weakness and may cause the patient to collapse to the ground. So far, pharmacotherapy of cataplexy and hypnagogic hallucinations has been predominantly based on tricyclic antidepressants. Recently, new drugs that block the reuptake of norepineprine and serotonin (e.g., venlafaxine) have been suggested as first-line treatment. These drugs have become our choice in treating children with cataplexy and nightmares as a symptom in narcolepsy.

METHODS

We describe clinical case reports of venlafaxine treatment in 6 children aged 7-12 years old when diagnosed with narcolepsy-cataplexy.

RESULTS

In 2 cases with up to 50 daily cataplectic attacks, an initial effect of 37.5 mg of venlafaxine was initially observed. However, during the first year, the dose had to be increased to 112.5 mg daily to avoid cataplexy. A third patient with partial cataplexy was treated with 75 mg of venlafaxine daily. In 2 cases, hypnagogic hallucinations, described by the patients as nightmares, were the most troubling symptom and were successfully treated with only 37.5 mg of venlafaxine daily. Side effects included an increase of disturbed nocturnal sleep when venlafaxine was taken after 2:00 p.m. No major aggressive or suicidal thoughts and no raised blood pressure were recorded.

CONCLUSION

Venlafaxine has proven to be an effective treatment of cataplexy and hypnagogic hallucinations in 6 children with narcolepsy. No severe side effects were observed.

Are children just small adults? The differences between paediatric and adult sleep medicine

Several important physiological and maturational changes occur in sleep development during the paediatric age range, particularly during infancy and in early childhood. As the pathology of sleep apnoea is superimposed onto a developing and often plastic physiological system, children often show a different pathophysiology to their adult counterparts. These factors need to be incorporated into the evaluation of a child's sleep problems. Particular attention should be paid to the developmental stage of the child. Investigation, interpretation and subsequent management provide further unique challenges and during successive reviews predicted normal changes must also be taken into account. This review article discusses the important physiological and maturational changes that occur in sleep during childhood, some common paediatric sleep conditions and their presentation and the appropriate evaluation and management of these conditions. In the course of the discussion, we have stressed important differences between paediatric and adult sleep medicine.

Sleep disorders in children

INTRODUCTION

Sleep disorders may affect 20-30% of young children, and include excessive daytime sleepiness, problems getting to sleep (dysomnias), or undesirable phenomena during sleep (parasomnias), such as sleep terrors, and sleepwalking. Children with physical or learning disabilities are at increased risk of sleep disorders.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for dysomnias in children? What are the effects of treatments for parasomnias in children? We searched: Medline, Embase, The Cochrane Library and other important databases up to September 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 14 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: antihistamines, behavioural therapy plus benzodiazepines, or plus chloral and derivates, exercise, extinction and graduated extinction, light therapy, melatonin, safety/protective interventions for parasomnias, scheduled waking (for parasomnias), sleep hygiene, and sleep restriction.

Comparative analysis of multiple sleep latency tests (MSLT) parameters and occurrence of dreaming in patients with daytime sleepiness of narcoleptic and non-narcoleptic origin

OBJECTIVE

To compare MSLT parameters in two groups of patients with daytime sleepiness, correlated to the occurrence and onset of dreams.

METHOD

Patients were submitted to the MSLT between January/1999 and June/2002. Sleep onset latency, REM sleep latency and total sleep time were determined. The occurrence of dreams was inquired following each MSLT series. Patients were classified as narcoleptic (N) or non-narcoleptic (NN).

RESULTS

Thirty patients were studied, 12 were classified as narcoleptics (N group; 40%), while the remaining 18 as non-narcoleptic (NN group; 60%). Thirty MSLT were performed, resulting in 146 series. Sleep was detected in 126 series (86%) and dreams in 56 series (44.44%). Mean sleep time in the N group was 16.0+/-6.3 min, while 10.5+/-7.5 min in the NN group (p<0.0001). Mean sleep latency was 2.0+/-2.2 min and 7.2+/-6.0 min in the N and NN group, respectively (p<0.001). Mean REM sleep latency in the N group was 3.2+/-3.1min and 6.9+/-3.7 min in the NN group (p=0.021). Dreams occurred in 56.9% of the N group series and 28.4% in that of the NN group (p=0.0009). Dream frequency was detected in 29.8% and 75% of the NREM series of the N and NN groups, respectively (p=0.0001).

CONCLUSION

Patients from the N group, compared to the NN group, slept longer and earlier, demonstrated a shorter REM sleep onset and greater dream frequency. NN patients had a greater dream frequency in NREM series. Thus, the occurrence of dreams during NREM in the MSLT may contribute to differentially diagnose narcolepsy and daytime sleepiness.

The protean manifestations of childhood narcolepsy and their misinterpretation

Narcolepsy often begins in childhood but is infrequently recognized, partly because of its many manifestations that can be confused with other conditions. The clinical presentations of excessive sleepiness, cataplexy, hallucinatory phenomena, and sleep paralysis (not always occurring together) are very varied. The picture may be further complicated by the occurrence of automatic behaviour, memory and visual problems, and associated sleep disorders, as well as the psychological and social consequences of having narcolepsy. Not surprisingly, therefore, misinterpretation of the symptoms as primarily psychological, or otherwise physical, may well occur leading to inappropriate management including initial referral to psychiatric or educational rather than neurological or sleep disorder services. The wide-ranging and special features of childhood narcolepsy need to be appreciated by health care and other professionals as well as by parents.

The sleepy child

Disorders of excessive sleepiness are uncommon in children. When they occur, the presentation is often consistent with the developmental age of the child and does not meet either historical or laboratory criteria determined with adults in mind. Because of these differences, the true diagnosis can be missed or inadequately treated. Knowledge of the differences in presentation, diagnosis, and treatment between adult and childhood sleep disorders is imperative to prevent serious cardiac, respiratory, psychiatric, and cognitive morbidity.

Factors associated with a delay in the diagnosis of narcolepsy

BACKGROUND

There can be a long interval from the onset of symptoms before a diagnosis of narcolepsy is made. There are no multivariate analyses reported in the literature of factors that may contribute to this delay. The aims of this study were to describe the delay in diagnosis of people with narcolepsy living in the UK and to identify associated factors.

METHODS

The study comprised a postal survey of 500 members of the Narcolepsy Association UK, which included questions regarding age of onset of symptoms, year of diagnosis and subject demographics. Cox's proportional hazards regression was performed.

RESULTS

A total of 313 questionnaires were returned of which 219 had been completed sufficiently for analysis. The interval between symptom onset and diagnosis ranged from within 1 to 61 years with a median of 10.5 years. Multivariate analysis showed that the presence of cataplexy as one of the initial symptoms and a more recent year of symptom onset were the only factors associated with time to diagnosis.

CONCLUSIONS

We have confirmed that the diagnosis of narcolepsy can be delayed for many years particularly when cataplexy is absent initially. The delay in diagnosis in the UK appears to be decreasing, probably through greater doctor and patient awareness of the clinical manifestations of narcolepsy.

Diagnosis and treatment of sleep disorders: a brief review for clinicians

Sleep disorders encompass a wide spectrum of diseases with significant individual health consequences and high economic costs to society. To facilitate the diagnosis and treatment of sleep disorders, this review provides a framework using the International Classification of Sleep Disorders, Primary and secondary insomnia are differentiated, and pharmacological and nonpharmacological treatments are discussed. Common circadian rhythm disorders are described in conjunction with interventions, including chronotherapy and light therapy. The diagnosis and treatment of restless legs syndrome/periodic limb movement disorder is addressed. Attention is focused on obstructive sleep apnea and upper airway resistance syndrome, and their treatment. The constellation of symptoms and findings in narcolepsy are reviewed together with diagnostic testing and therapy, Parasomnias, including sleep terrors, somnambulism, and rapid eye movement (REM) behavior sleep disorders are described, together with associated laboratory testing results and treatment.

Medication for sleep-wake disorders

Medication is indicated for only a limited number of children's sleep disorders. However, correctly chosen and supervised, pharmacological treatment may be justified and helpful. For a given sleep problem it is important to identify the underlying cause (or sleep disorder) which often calls for treatment of a non-medication type. Where medication is appropriate, cautious use and careful review of the child's physical and psychological state is essential in view of the limited information available on effectiveness and possible short and long term effects. It follows that much further research is required to establish the part medication can play in the care of children with sleep disorders, and also to define the possible effects on sleep and wakefulness of other drugs used in clinical practice.

Annotation: The use of psychotropic medications in children: a British view

BACKGROUND

Prescribing practices relating to the use of psychotropic medication with mentally disordered children have changed significantly in Britain over recent years.

METHODS

I conducted a review of the modest body of empirical data available relating to the prescribing practices of child psychiatrists, paediatricians and general practitioners (primary care physicians). The data were obtained primarily from postal questionnaire studies but also from British drug studies and a government-sponsored evaluation of the efficacy of stimulant medication. Postgraduate training guidelines for the three principal clinical disciplines are also discussed.

RESULTS

Systematic evaluation of prescribing practices has a relatively short history. All the studies reviewed demonstrated consistent methodological weaknesses, the most important of which was reliance upon retrospective reports of prescribing practices from clinicians with no analysis of actual prescription data. No studies relating to the general use of psychotropic medication by paediatricians were found. Child psychiatrists and general practitioners appear to be using a range of drugs for a range of conditions; however, there was evidence of intra- and interdisciplinary variations in practice. It was also evident from the general practitioner data that drug treatments were frequently used for conditions best managed with behavioural methods (e.g., common sleep problems and enuresis). Government prescription data relating to methylphenidate use in ADHD reveal a dramatic rise over the past ten years. Currently, most child psychiatrists use this treatment compared to approximately half the profession only seven years ago. The use of newer antipsychotic agents as well as the SSRI antidepressants appears to be growing in child psychiatric practice. A majority of clinicians surveyed believed that medication was an important treatment modality but also felt that they were relatively unskilled in the field and requested further training.

CONCLUSIONS

Overall, a picture of both a growing and better informed use of psychotropic medication is emerging in Britain despite shortcomings in postgraduate training. Future research needs to evaluate prescribing practice in a more objective manner in order to improve training and also service developments in the field.

Use of psychostimulant medication for ADHD in South Australia

OBJECTIVE

A retrospective analysis of archival data on psychostimulant prescriptions from South Australia for the period 1990 to 2000 for 5,189 youths from birth to age 18 years was conducted.

METHOD

A person-based data set was used to assess (1) rate of new prescriptions by age group, (2) demographic characteristics (age of psychostimulant start, male-to-female ratio), (3) duration of psychostimulant use, and (4) geographic variation in psychostimulant prescription.

RESULTS

Four major findings were observed: (1) the rate of new prescriptions increased dramatically until 1995 but is now declining; (2) demographic characteristics and changes over time mirror those observed in the United States; (3) median duration of psychostimulant use (for a subset of 1,688 children) was approximately 2.5 years; and (4) there was a significant correlation between geographic location and prescription rate.

CONCLUSIONS

The patterns of psychostimulant use in Australia closely parallel U.S. patterns. Physicians'prescribing practices may be extremely volatile. Duration of medication treatment should receive increased attention. There is pronounced geographic variability in prescription rates which may be related to socioeconomic status.

Schlafstörungen bei kinder- und jugendpsychiatrischen Erkrankungen

Zusammenfassung: Schlafstörungen als Symptom zahlreicher kinder- und jugendpsychiatrischer Störungsbilder komplizieren häufig den Verlauf und die Behandlung der Grunderkrankung. Organische Störungen wie die Narkolepsie oder das Kleine-Levin-Syndrom können zu differentialdiagnostischen Schwierigkeiten und Fehleinschätzungen führen. Unklar ist, ob spezifische Veränderungen der Schlafarchitektur bereits im Kindes- und Jugendalter bestehen und damit als biologischer Trait-Marker für psychiatrische Erkrankungen zu verstehen sind. Während für das Erwachsenenalter die Bedeutung von Schlafstörungen vor allem für die Entwicklung späterer depressiver Störungen belegt werden konnte, ist derzeit offen, ob es sich bei persistierenden Schlafstörungen im Kindesalter um Vulnerabilitätsmarker für psychiatrische Erkrankungen handelt. In der vorliegenden Literaturübersicht sollen Wechselwirkungen zwischen Schlafstörung und psychischer Störung aufgezeigt und die Bedeutung der Berücksichtigung von Schlafstörungen für Diagnostik und Therapie kinder- und jugendpsychiatrischer Störungsbilder unterstrichen werden.

Childhood sleep disorders: diagnostic and therapeutic approaches

Pediatric sleep physiology begins with development of the sleep/wake cycle, and the origins of active versus quiet sleep. The 24-hour circadian cycle becomes established at 3 to 6 months. Sleep disorders are rationally approached in pediatrics as age-related. Disorders during infancy commonly include mild, usually self-limited conditions such as sleep-onset association disorder, excessive nighttime feedings, and poor limit-setting. These require behavioral management to avoid long-term deleterious sleep habits. In contrast, other sleep disorders are more ominous, including sudden infant death syndrome (SIDS), central congenital hypoventilation syndrome, and sleep apnea. Childhood is generally the golden age of sleep, with brief latency, high efficiency, and easy awakening. Parasomnias, sometimes stage specific, are manifest here. Adolescents have sleep requirements similar to preteens, posing a challenge for them to adapt to school schedules and lifestyles. Narcolepsy, usually diagnosed in adolescence or early adulthood, is a lifelong sleep disorder that has led to the identification of the hypocretin/orexin neurotransmitter system. This will lead to enhanced understanding of what regulates stage rapid eye movement, and to novel therapeutic advances for hypersomnolence.

Assessment of sleepiness in children

Excessive sleepiness is a common but under-recognized problem in children. This article examines the clinical and laboratory evaluation of sleepiness in children, including the use of polysomnography, the multiple sleep latency test, and other varieties of neurophysiologic testing. Where applicable, technical aspects of laboratory testing are reviewed. Alternative laboratory and neurobehavioral techniques used to investigate daytime sleepiness are also briefly covered.