EFNS guidelines on management of narcolepsy

Rapid eye movement sleep behavior disorder and rapid eye movement sleep without atonia in narcolepsy

Narcolepsy is a rare disabling hypersomnia disorder that may include cataplexy, sleep paralysis, hypnagogic hallucinations, and sleep-onset rapid eye movement (REM) periods, but also disrupted nighttime sleep by nocturnal awakenings, and REM sleep behavior disorder (RBD). RBD is characterized by dream-enacting behavior and impaired motor inhibition during REM sleep (REM sleep without atonia, RSWA). RBD is commonly associated with neurodegenerative disorders including Parkinsonisms, but is also reported in narcolepsy in up to 60% of patients. RBD in patients with narcolepsy is, however, a distinct phenotype with respect to other RBD patients and characterized also by absence of gender predominance, elementary rather than complex movements, less violent behavior and earlier age at onset of motor events, and strong association to narcolepsy with cataplexy/hypocretin deficiency. Patients with narcolepsy often present dissociated sleep features including RSWA, increased density of phasic chin EMG and frequent shift from REM to NREM sleep, with or without associated clinical RBD. Most patients with narcolepsy with cataplexy lack the hypocretin neurons in the lateral hypothalamus. Tonic and phasic motor activities in REM sleep and dream-enacting behavior are mostly reported in presence of cataplexy. Narcolepsy without cataplexy is a condition rarely associated with hypocretin deficiency. We proposed that hypocretin neurons are centrally involved in motor control during wakefulness and sleep in humans, and that hypocretin deficiency causes a functional defect in the motor control involved in the development of cataplexy during wakefulness and RBD/RSWA/phasic motor activity during REM sleep.

Clinical assessment and management of sleep disorders in multiple sclerosis: a literature review

The major sleep disorders are common in multiple sclerosis (MS) and are associated with significant morbidity. Despite this, the rate of recognition and management of these conditions are low. All types of sleep disorders are seen in patients with MS: insomnia, circadian rhythm sleep disorders, sleep-related movement disorders, sleep-related breathing disorders, hypersomnia (narcolepsy), and parasomnia (REM sleep behavior disorder; RBD). This literature review covers the prevalence, clinical features, and treatment of sleep disorders in MS. Based on clinical experience, the spectrum of symptoms associated with MS, and the current knowledge of MS pathophysiology, we have also enclosed proposed strategies for clinical assessment and investigation of sleep disorders in MS patients.

Diagnosis and management of central hypersomnias

Central hypersomnias are diseases manifested in excessive daytime sleepiness (EDS) not caused by disturbed nocturnal sleep or misaligned circadian rhythms. Central hypersomnias includes narcolepsy with and without cataplexy, recurrent hypersomnia, idiopathic hypersomnia, with and without long sleep time, behaviorally induced insufficient sleep syndrome, hypersomnia and narcolepsy due to medical conditions, and finally hypersomnia induced by substance intake. The Epworth Sleepiness Scale is a subjective tool mostly used for EDS assessment, while the Multiple Sleep Latency Test serves as an objective diagnostic method for narcolepsy and idiopathic hypersomnias. As for symptomatic therapy of EDS, the central nervous system stimulants modafinil and methylphenidate seem to work well in most cases and in narcolepsy and Parkinson's disease; sodium oxybate also has notable therapeutic value.

The use of sodium oxybate to treat narcolepsy

Narcolepsy is a life-long neurodegenerative disorder that causes considerable impairment to quality of life. Until the 1970s, the treatment for one of the main symptoms, excessive daytime sleepiness, was restricted to stimulants, whereas the second core symptom, cataplexy, was treated with antidepressants, and the resultant fragmented night-time sleep with hypnotics. Sodium oxybate (Xyrem(®), UCB Pharma, Brussels, Belgium) is an efficacious drug for all three symptoms which improves the quality of life of narcoleptic patients. Owing to its metabolic pathway, there is very little pharmacokinetic interaction with other drugs. In combination with modafinil, some of its therapeutic benefits are enhanced. Adverse events and side effects are moderate when taken according to indication and as recommended. Essential limitations have to be considered before starting the treatment (sleep-related breathing disorders, alcohol intake, hypnotic and sedative comedication, and epilepsy). This article gives an overview of sodium oxybate, which has been US FDA approved for the treatment of cataplexy and excessive daytime sleepiness in patients with narcolepsy, and EMA approved for the treatment of narcolepsy-cataplexy.

Predictors of hypocretin (orexin) deficiency in narcolepsy without cataplexy

STUDY OBJECTIVES

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

SETTING

University-based sleep clinics and laboratories.

PATIENTS

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

DESIGN AND INTERVENTIONS

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

MEASUREMENTS AND RESULTS

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

CONCLUSION

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

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

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

Excessive daytime sleepiness and narcolepsy--an approach to investigation and management

Excessive daytime sleepiness is a common presentation to physicians both in general practice and hospital settings. In this review, we provide an update on the latest theories on the pathogenesis of the condition, and discuss the approach to investigation of the sleepy patient, with particular reference to narcolepsy. Recommended therapy is reviewed for both narcolepsy and cataplexy, to provide physicians with an important reference on the investigation and management of these troubling conditions.

Injurious REM sleep behaviour disorder in narcolepsy with cataplexy contributing to criminal proceedings and divorce

We present a case of violent sleep-related behaviour in a patient with narcolepsy with cataplexy (NC) and REM sleep behaviour disorder (RBD), causing injuries to his wife that resulted in charge of assault, followed by a divorce case. This observation pinpoints that RBD in NC can arise early in a patient's life and that it can be violent, that pharmacological treatment for RBD has to be considered in this case, that lack (or delay) of RBD diagnoses may further exacerbate the psychosocial burden of NC, and that a general awareness of the nature of sleep related violence may avoid unfortunate legal and personal consequences for patients, their partners and families.

British Association for Psychopharmacology consensus statement on evidence-based treatment of insomnia, parasomnias and circadian rhythm disorders

Sleep disorders are common in the general population and even more so in clinical practice, yet are relatively poorly understood by doctors and other health care practitioners. These British Association for Psychopharmacology guidelines are designed to address this problem by providing an accessible up-to-date and evidence-based outline of the major issues, especially those relating to reliable diagnosis and appropriate treatment. A consensus meeting was held in London in May 2009. Those invited to attend included BAP members, representative clinicians with a strong interest in sleep disorders and recognized experts and advocates in the field, including a representative from mainland Europe and the USA. Presenters were asked to provide a review of the literature and identification of the standard of evidence in their area, with an emphasis on meta-analyses, systematic reviews and randomized controlled trials where available, plus updates on current clinical practice. Each presentation was followed by discussion, aimed to reach consensus where the evidence and/or clinical experience was considered adequate or otherwise to flag the area as a direction for future research. A draft of the proceedings was then circulated to all participants for comment. Key subsequent publications were added by the writer and speakers at draft stage. All comments were incorporated as far as possible in the final document, which represents the views of all participants although the authors take final responsibility for the document.

The socio-economical burden of hypersomnia

OBJECTIVES

In the absence of socio-economical consequences of hypersomnia this study addresses the factual indirect and direct costs.

METHODS

Two thousand two hundred and eight patients with a hypersomnia diagnosis from 1998 to 2005 were identified in the Danish national patient registry (NPR), each compared with 4 age and gender adjusted, randomly chosen citizens selected from the Civil Registration System Statistics. The health cost was decomposed in direct and indirect yearly costs, including labor supply and social transfer payments. Direct costs included frequencies and costs of discharges and outpatient use by cost weights according to diagnosis related groups and specific outpatient prices based on data from The Danish Ministry of Health. The use of and costs of drugs was based on data from the Danish Medicines Agency. The frequencies and costs from primary sectors were based on data from The National Health Security. Indirect costs were based on income data from the coherent social statistics (CSS).

RESULTS

Patients with hypersomnia presented significant higher health related contact rate, expenses and medication use. No differences were identified in employment and income. The yearly sum of direct and indirect costs were yearly euro3402 vs. euro1212 in controls (P < 0.001), corresponding to a yearly excess costs euro2190. The patients presented higher transfer income, total euro889.

CONCLUSION

Hypersomnia patient present higher health and medication uses, and social transfer income and thus represent a significant socio-economical burden.

A review of tolerability and abuse liability of gamma-hydroxybutyric acid for insomnia in patients with schizophrenia

BACKGROUND

Approved therapeutic uses for gamma-hydroxybutyric acid (GHB) (or sodium oxybate), a gamma-aminobutyric acid type B and GHB receptor agonist, include narcolepsy in the United States and Europe and alcohol abuse treatment in Italy. Possible efficacy of GHB in schizophrenia has also been proposed. A tolerability concern regarding use of GHB is its abuse potential. Given the high comorbidity of substance disorders and schizophrenia, a systematic assessment of the published literature is crucial.

OBJECTIVE

The aim of this review was to assess the tolerability and abuse liability of GHB in the context of future clinical studies as a potential treatment for insomnia in patients with schizophrenia.

METHODS

A literature search in English (inception through April 2009, inclusive) was conducted of MEDLINE, EMBASE, and PsycINFO using the search term GHB. All articles whose abstracts mentioned human use of GHB were read in their entirety. The reference sections of identified articles were reviewed for publications that might have been missed by the initial search.

RESULTS

GHB is abused by a small percentage of people (<1%) as a "club drug" and is commonly associated with enhanced sexual experiences (65%), euphoria (41%), somnolence (71%), and confusion (24%), according to a recent study. A review of all available emergency room case series suggests that while GHB can be associated with serious coma necessitating intubation, the number of reported fatal cases associated with GHB appears limited. Clarity on the lethality of GHB is complicated by instability of GHB in postmortem samples and frequent concomitant ingestions. Furthermore, formal abuse liability studies do not support high abuse propensity for GHB, mainly because oversedation and dizziness may lead most individuals to find GHB unpleasant at high doses. As supported by 2 large studies, there is limited evidence to suggest widespread use as an agent in sexual assault. Years of clinical use in narcolepsy do not support the development of tolerance or withdrawal in those subjects without substance dependence.

CONCLUSIONS

Tolerability and abuse liability issues, while a concern with GHB given its abuse potential, do not preclude further study of the potential use for insomnia in nondually diagnosed schizophrenia. Full cognizance must be taken of risk/benefit tradeoffs, and to the development of improved formulations with decreased abuse liability.

[Narcolepsy with and without cataplexy: an uncommon disabling and unrecognized disease]

Although narcolepsy is a relatively uncommon condition, its impact on a child's life can be dramatic and disabling. Narcolepsy is characterized by excessive daytime sleepiness (EDS), with brief "sleep attacks" at very unusual times and usually associated with cataplexy (sudden loss of muscle control while awake, resulting in a fall, triggered by laughter). Other symptoms frequently reported are sleep paralysis (feeling of being unable to move or speak, even totally aware), hypnagogic hallucinations (vivid dreamlike experiences difficult to distinguish from reality) or disturbed night time sleep. Some children also experience depression or overweight-obesity. Although narcolepsy has been thoroughly studied, the exact cause is unknown. It appears to be a disorder of cerebral pathways that control sleep and wakefulness, involving dorsolateral hypothalamus and hypocretin. A genetic factor has been suggested, but narcolepsy in relatives is rare. Researchers have suggested that a set of genes combines with additional factors in a person's life to cause narcolepsy. The effective treatment of narcolepsy requires not only medication (usually stimulants, antidepressants and sodium oxybate), but also adjustments in life-style (scheduled naps). Management of this condition in children demands a comprehensive approach to the patient, that includes a correct diagnosis, pharmacological and non-pharmacological treatment and adjustments in the environment. These strategies can improve the child's self-esteem and ability to obtain a good education.

[Narcolepsy and other hypersomnias]

BACKGROUND

Narcolepsy is currently categorized into three groups; narcolepsy with and without emotionally triggered loss of muscle tone (cataplexy), and narcolepsy secondary to other medical conditions. Many patients with hypersomnia are diagnosed too late. The article presents a review of this field.

MATERIAL AND METHODS

Sources are literature identified through a non-systematic Pub-Med search and the authors' personal experience with diagnosing and treating patients with narcolepsy and other hypersomnias.

RESULTS

Sleep attacks and emotionally triggered loss of muscle tone are the most important symptoms of narcolepsy with cataplexy. Loss of hypocretin-producing cells is considered to be the cause. Absence of the tissue antigen HLA DQB1*0602 renders narcolepsy an unlikely diagnosis. Narcolepsy without cataplexy occurs less frequently and may have another biological basis. A differential diagnostic evaluation is important to determine whether hypersomnia is associated with obstructive sleep apnea, neurological disease or psychiatric disorders. Polysomnography and multiple sleep latency tests are important diagnostic tools. Hypocretine levels in the cerebrospinal fluid should be measured in most patients. Methylphenidate and other CNS-stimulants are the most potent drugs for treatment of sleep attacks. Tricyclic antidepressive drugs and some newer drugs may be efficient in cataplexy.

INTERPRETATION

Narcolepsy may affect education and work-life. Medication is available. Regular general practitioners should refer patients suspected of having narcolepsy for evaluation in a sleep centre or a hospital with established routines for diagnosis of sleep disorders.

Treatment of narcolepsy

Narcolepsy is a neurological disorder characterized, in its classical form, by excessive daytime sleepiness (EDS) with irresistible episodes of sleep, cataplexy, disrupted nocturnal sleep, hypnagogic/hypnopompic hallucinations and sleep paralysis. It is often under-diagnosed, however, if it is suitably diagnosed, symptoms can be well treated by means of targeted drugs, such as modafinil to treat EDS, sodium oxybate for cataplexy, as well as EDS and disrupted nocturnal sleep, and tricyclic and newer antidepressants for cataplexy. Hallucinations and sleep paralysis can be treated with the same drugs used for cataplexy. Amphetamines and amphetamine-like stimulants are used less nowadays. Behavioral measures are also important and useful. The discovery of hypocretin deficiency in narcoleptic patients opens new perspectives for the development of newer therapeutic approaches for both EDS and cataplexy. Therapy for narcolepsy is chronic, hence symptomatic. However, the correct use of available drugs enables patients to gain a better quality of life, keeping the symptoms under control, which, mainly from a social point of view, are heavily disabling.

Differential effects of acute and repeat dosing with the H3 antagonist GSK189254 on the sleep-wake cycle and narcoleptic episodes in Ox-/- mice

BACKGROUND AND PURPOSE

Histamine H3 receptor antagonists are currently being evaluated in clinical trials for a number of central nervous system disorders including narcolepsy. These agents can increase wakefulness (W) in cats and rodents following acute administration, but their effects after repeat dosing have not been reported previously.

EXPERIMENTAL APPROACH

EEG and EMG recordings were used to investigate the effects of acute and repeat administration of the novel H3 antagonist GSK189254 on the sleep-wake cycle in wild-type (Ox+/+) and orexin knockout (Ox-/-) mice, the latter being genetically susceptible to narcoleptic episodes. In addition, we investigated H3 and H1 receptor expression in this model using radioligand binding and autoradiography.

KEY RESULTS

In Ox+/+ and Ox-/- mice, acute administration of GSK189254 (3 and 10 mg x kg(-1) p.o.) increased W and decreased slow wave and paradoxical sleep to a similar degree to modafinil (64 mg x kg(-1)), while it reduced narcoleptic episodes in Ox-/- mice. After twice daily dosing for 8 days, the effect of GSK189254 (10 mg x kg(-1)) on W in both Ox+/+ and Ox-/- mice was significantly reduced, while the effect on narcoleptic episodes in Ox-/- mice was significantly increased. Binding studies revealed no significant differences in H3 or H1 receptor expression between Ox+/+ and Ox-/- mice.

CONCLUSIONS AND IMPLICATIONS

These studies provide further evidence to support the potential use of H3 antagonists in the treatment of narcolepsy and excessive daytime sleepiness. Moreover, the differential effects observed on W and narcoleptic episodes following repeat dosing could have important implications in clinical studies.

Evidence-based recommendations for the assessment and management of sleep disorders in older persons

Sleep-related disorders are most prevalent in the older adult population. A high prevalence of medical and psychosocial comorbidities and the frequent use of multiple medications, rather than aging per se, are major reasons for this. A major concern, often underappreciated and underaddressed by clinicians, is the strong bidirectional relationship between sleep disorders and serious medical problems in older adults. Hypertension, depression, cardiovascular disease, and cerebrovascular disease are examples of diseases that are more likely to develop in individuals with sleep disorders. Conversely, individuals with any of these diseases are at a higher risk of developing sleep disorders. The goals of this article are to help guide clinicians in their general understanding of sleep problems in older persons, examine specific sleep disorders that occur in older persons, and suggest evidence- and expert-based recommendations for the assessment and treatment of sleep disorders in older persons. No such recommendations are available to help clinicians in their daily patient care practices. The four sections in the beginning of the article are titled, Background and Significance, General Review of Sleep, Recommendations Development, and General Approach to Detecting Sleep Disorders in an Ambulatory Setting. These are followed by overviews of specific sleep disorders: Insomnia, Sleep Apnea, Restless Legs Syndrome, Circadian Rhythm Sleep Disorders, Parasomnias, Hypersomnias, and Sleep Disorders in Long-Term Care Settings. Evidence- and expert- based recommendations, developed by a group of sleep and clinical experts, are presented after each sleep disorder.

Modafinil in the treatment of excessive sleepiness

The wake-promoting agent modafinil is approved for the treatment of excessive sleepiness associated with obstructive sleep apnea (OSA), shift work disorder (SWD), and narcolepsy. In OSA, modafinil is recommended for use as an adjunct to standard therapies that treat the underlying airway obstruction. This article reviews the literature on modafinil (pharmacology, pharmacokinetics, efficacy, tolerability, and abuse potential), with emphasis on use of modafinil in the treatment of excessive sleepiness in patients with OSA, SWD, and narcolepsy. In large-scale, double-blind, placebo-controlled studies, modafinil improved objectively determined sleep latency, improved overall clinical condition related to severity of sleepiness, and reduced patient-reported sleepiness. Improvements in wakefulness were accompanied by improvements in behavioral alertness, functional status, and health-related quality of life. In patients with SWD, diary data showed modafinil reduced the maximum level of sleepiness during night shift work, level of sleepiness during the commute home, and incidence of accidents or near-accidents during the commute home when compared with placebo. Modafinil was well tolerated, without adversely affecting cardiovascular parameters or scheduled sleep. These findings and those of extension studies which reported improvements were maintained suggest modafinil has a beneficial effect on daily life and well-being in patients with excessive sleepiness associated with OSA, SWD, or narcolepsy.

Management of narcolepsy

BACKGROUND

Narcolepsy is a rare chronic sleep disorder classically characterized by excessive daytime sleepiness. Other symptoms of the disease, including cataplexy, sleep paralysis, hypnagogic hallucinations and disturbed nocturnal sleep, may follow later. The disease can be incapacitating and frequently results in impaired psychosocial interaction. In the absence of a cure for narcolepsy, medical therapy is directed at symptom control.

OBJECTIVES

The aim of this study was to review the current approach to the treatment of narcolepsy.

METHODS

A search of three bibliographic databases (MEDLINE/PubMed, EMBASE and the Cochrane Library Database) was conducted from 1966 to January 2008 using the National Library of Medicine MeSH search terms narcolepsy and cataplexy. Relevant studies, case reports, review articles, editorials, short communications and chapters from selected textbooks were then extracted and manually cross-referenced.

RESULTS/CONCLUSIONS

Traditionally, stimulants have been used to improve the symptoms of excessive daytime sleepiness. However, the treatment of narcolepsy has evolved recently with the widespread use of newer drugs, including modafinil for daytime sleepiness, newer antidepressants for cataplexy and gamma-hydroxybutyrate (sodium oxybate) for both excessive daytime sleepiness and cataplexy.

Nocturnal aspects of narcolepsy with cataplexy

Even though the most impressive manifestation of narcolepsy is excessive sleepiness, paradoxically a significant number of patients have trouble sleeping at night. A wide array of alterations can affect the night-time sleep of a narcoleptic patient, and the aim of this review is to increase awareness on this issue, thereby enhancing the care of narcoleptic patients by more specific approaches to their disturbed night sleep. This review covers a broad variety of nocturnal sleep features in narcolepsy. Starting from animal models and the clinical features of patients, the paper then discusses the many comorbid conditions found in narcolepsy at night, the most advanced methods of analysis and the few recent advances in the specific treatment of night sleep in narcoleptic patients.

Therapies for narcolepsy with or without cataplexy: evidence-based review

(1) Narcolepsy is a rare disorder of unknown aetiology characterized by excessive daytime sleepiness and typically associated with cataplexy. It is extremely incapacitating, and frequently results in impaired psychosocial functioning and reduced work performance. Currently there is no cure for narcolepsy, so treatment focuses on control of symptoms.(2) Although the sympathomimetic stimulants, such as amphetamines or methylphenidate, are effective in improving excessive daytime sleepiness in patients with narcolepsy, they have the potential for dependence, have sometimes disabling sympathomimetic side-effects and are associated with tolerance.(3) To date, there is clear evidence of the efficacy of modafinil, armodafinil and sodium oxybate in patients with narcolepsy. Modafinil and armodafinil improve excessive daytime sleepiness symptoms and have little abuse potential, but have no effect on cataplexy, so other drugs, such as antidepressants, are required to control cataplexy attacks.(4) Sodium oxybate improves both excessive daytime sleepiness and cataplexy. However, there is potential for abuse and possibly dependence.

Mésusage des médicaments du sommeil et de la vigilance

Sleep disorders, mainly insomnia and daytime somnolence, can arise from very different causes. For example insomnia may be related to anxiety-depression or occur in response to a stressful lifestyle or as an element of restless leg syndrome. Subjects with hypersomnia may present episodes of sleep apnea, drug-related depression or narcolepsia. Specific management is required for each etiology. Misuse of sleep drugs generally results from an insufficient etiological diagnosis and a misunderstanding of their proper use. These drugs can be used as necessary expedients but cannot replace correct management or treatment of the cause or causes of the sleep disorder. We present here a review of the undesirable effects, particularly among the elderly population, and of the risk of addiction to the different drugs used to induce sleep in order to propose prescription guidelines.

Sodium oxybate: a review of its use in the management of narcolepsy

Sodium oxybate (Xyrem) is the sodium salt of the CNS depressant gamma-hydroxybutyric acid (GHB) and is therefore subject to prescription restrictions. It is approved in the US for the treatment of cataplexy and excessive daytime sleepiness (EDS) in patients with narcolepsy, and in the EU for the treatment of narcolepsy with cataplexy. Sodium oxybate is generally well tolerated and effective in the treatment of symptoms of narcolepsy with cataplexy. While its short half-life necessitates twice-nightly administration, it is highly effective in reducing the frequency of cataplexy, improving sleep architecture and reducing EDS in patients with narcolepsy. Sodium oxybate therefore offers a valuable alternative or addition to the use of TCAs, SSRIs and stimulants in the treatment of the symptoms of narcolepsy including cataplexy and EDS.

Persistent sleepiness in CPAP treated obstructive sleep apnea patients: evaluation and treatment

Nasal continuous positive airway pressure (CPAP) is an effective treatment for most patients with obstructive sleep apnea syndrome (OSAS), improving sleepiness, cognitive function and mood. A number of patients, however, complain about persistent sleepiness after CPAP. In these cases another clinical history should be carried out to confirm the diagnosis of OSAS, to check CPAP compliance and to exclude associated conditions such as poor sleep hygiene, depression, narcolepsy or idiopathic hypersomnia. If necessary, a full polysomnography (PSG) followed by a multiple sleep latency test or even a full PSG with CPAP titration should be performed. Experimental data in animals suggest that long-term intermittent hypoxia related to the apneic events could deteriorate the brain structures that regulate alertness. This impairment, if present in humans, could be another reason for residual sleepiness after CPAP. Modafinil has been shown to reduce subjective sleepiness after CPAP in OSAS patients. Further studies are warranted to clarify the way in which CPAP modifies sleepiness.