Diagnosis Of Narcolepsy Research Articles

What Has Been Going on With My Sleep After My Car Accident?

INTRODUCTION: Hypnagogic hallucinations are hallucinatory experiences that accompany the onset of awakening, they can occur in certain states, such as sleep deprivation and conditions such as narcolepsy. Main neural structures responsible for muscle atonia in REM sleep are dorsolateral portions of the pons and brainstem, cholinergic and cholinoceptive REM sleep-on neurons, monoaminergic REM sleep-off neurons. Generalized atonia originates in dorsolateral portions of the pontine reticular formation and descend to the medulla and spinal cord to bring postural atonia. Muscle atonia characteristic of REM sleep produces both cataplexy and sleep paralysis. Disruptions induced experimentally of these neurons can cause REM sleep without atonia. Reports on narcolepsy following traumatic brain injury have been previously described in the literature.CASE PRESENTATION: We report a case of a 25 year old woman referred to Sleep Clinic with complaints of episodes of drifting off and suffocating while in bed for about 2 years, with visual hallucinations of a figure in the room or the surroundings, feeling paralyzed during these episodes, that occur approximately 3 to four times per week, sometimes occuring more than once per night. Sleep paralysis, nightmares were described. Excessive daytime sleepiness was observed, with propensity to naps that could last 3 to 4 hours and were refreshing. Epworth Sleepiness scale was 6. There was no family history of parasomnias. She denied snoring or sleep attacks. She noticed the symptoms described occurred two years ago after a car accident, when she suffered a concussion. She had reported a recent 15 Lbs weight gain. On Physical exam she had an airway Mallampati class II and was obese (BMI 32) without any neurological findings. Polysomnography results were as follows: Total sleep time: 494 min (efficiency 93%), Sleep latency: 13 min and REM latency: 5 min. Sleep disordered breathing was not observed. Multiple Sleep Latency Test results were: Mean sleep latency of 10 min with mean REM latency of 7.7 min and 3 SOREMPs.DISCUSSION: We describe a case of Narcolepsy without cataplexy presenting after a concussion following a car accident. Prior associations with multiple sclerosis, encephalitis and had trauma have been reported, but the temporal relationship between these and the onset of symptoms were not clearly established. Hypnagogic hallucinations, sleep paralysis and nightmares are often present in the general population and may not warrant additional testing.CONCLUSIONS: In our patient, her excessive daytime sleepiness and temporal relationship with the diagnosis of concussion were helpful elucidating her final diagnosis of Narcolepsy.1) Castriotta R, Murthy J. Sleep disorders in patients with traumatic brain injury: A Reveiw. CNS Drugs; 2011, 25175-852) Clavelou P, Tournilhac M, Vidal C, et al. Narcolepsy associated with arteriovenous malformation of the diencephalon. Sleep; 1995, 18:202-5DISCLOSURE: The following authors have nothing to disclose: Veronica Brito, Chrisoula Politis, Shalinee ChawlaNo Product/Research Disclosure InformationWinthrop University Hospital, Mineola, NY. Language: en

Hypothermia, Hypotension, Hypersomnia, and Obesity Associated With Hypothalamic Lesions in a Patient Positive for the Anti–aquaporin 4 Antibody

To describe a patient positive for the anti-aquaporin 4 antibody with hypothalamic lesions showing hypothermia, hypotension, hypersomnia, and obesity. Case report. University hospital. We describe a 21-year-old woman who was positive for anti-aquaporin 4 antibody and presented with hypothermia, hypotension, and hypersomnia owing to bilateral hypothalamic lesions as the only abnormal clinical finding. Immediate steroid administration resulted in significant improvement of the patient's vital signs and imaging findings; however, her cognitive impairment and sleepiness persisted, and she subsequently developed obesity. Decreased cerebrospinal fluid orexin levels and sleep studies confirmed the diagnosis of narcolepsy due to medical condition. Physicians should be aware that neuromyelitis optica spectrum disorders can initially involve the hypothalamus. We emphasize that measurement of anti-aquaporin 4 antibody is of clinical importance in the differential diagnosis of hypothalamic lesions.

Daytime continuous polysomnography predicts MSLT results in hypersomnias of central origin

In the diagnostic work-up of hypersomnias of central origin, the complaint of excessive daytime sleepiness should be objectively confirmed by MSLT findings. Indeed, the features and diagnostic utility of spontaneous daytime sleep at 24 h continuous polysomnography (PSG) have never been investigated. We compared daytime PSG features to MSLT data in 98 consecutive patients presenting with excessive daytime sleepiness and with a final diagnosis of narcolepsy with cataplexy/hypocretin deficiency (n = 39), narcolepsy without cataplexy (n = 7), idiopathic hypersomnia without long sleep time (n = 19), and 'hypersomnia' with normal sleep latency at MSLT (n = 33). Daytime sleep time was significantly higher in narcolepsy-cataplexy but similar in the other groups. Receiver operating characteristics (ROC) curves showed that the number of naps during daytime PSG predicted a mean sleep latency ≤8 min at MSLT with an area under the curve of 0.67 ± 0.05 (P = 0.005). The number of daytime sleep-onset REM periods (SOREMPs) in spontaneous naps strikingly predicted the scheduled occurrence of two or more SOREMPs at MSLT, with an area under the ROC curve of 0.93 ± 0.03 (P < 10(-12) ). One spontaneous SOREMP during daytime had a sensitivity of 96% with specificity of 74%, whereas two SOREMPs had a sensitivity of 75%, with a specificity of 95% for a pathological REM sleep propensity at MSLT. The features of spontaneous daytime sleep well correlated with MSLT findings. Notably, the occurrence of multiple spontaneous SOREMPs during daytime clearly identified patients with narcolepsy, as well as during the MSLT.

Familial narcolepsy in the Lipizzaner horse: a report of three fillies born to the same sire

The occurrence of sleep disorder in three half sibling Lipizzaner is described. Sleepiness, swaying, stumbling, carpal joints buckling and falling down onto the carpal joints had been present since early foal age in all of them. Clinical signs had gradually reduced since the age of 2 years in cases 1 and 3. Sleepiness was induced by going out from the stable in adulthood. A physostigmine test was performed in all three affected horses and produced positive results in cases 1 and 3. The result of the test in case 2 was unclear due to the almost continuous sleepiness of the foal. Hypocretin-1 concentration in the cerebrospinal fluid was established using a standardised radioimmunoassay in case 1 (317.85 pg/mL), case 2 (303.43 pg/mL) and five adult control horses (275.2 ± 47.9 [SD] pg/mL) and was considered as normal in all horses. The sire of the affected horses has had 19 other registered offspring who did not show clinical signs of sleep disorder and also dams of all three cases produced healthy foals. Based on the demographic and clinical data together with the responses to the physostigmine challenges, the diagnosis of familial equine narcolepsy was made.

AS03 Adjuvanted AH1N1 Vaccine Associated with an Abrupt Increase in the Incidence of Childhood Narcolepsy in Finland

BackgroundNarcolepsy is a chronic sleep disorder with strong genetic predisposition causing excessive daytime sleepiness and cataplexy. A sudden increase in childhood narcolepsy was observed in Finland soon after pandemic influenza epidemic and vaccination with ASO3-adjuvanted Pandemrix. No increase was observed in other age groups.MethodsRetrospective cohort study. From January 1, 2009 to December 31, 2010 we retrospectively followed the cohort of all children living in Finland and born from January 1991 through December 2005. Vaccination data of the whole population was obtained from primary health care databases. All new cases with assigned ICD-10 code of narcolepsy were identified and the medical records reviewed by two experts to classify the diagnosis of narcolepsy according to the Brighton collaboration criteria. Onset of narcolepsy was defined as the first documented contact to health care because of excessive daytime sleepiness. The primary follow-up period was restricted to August 15, 2010, the day before media attention on post-vaccination narcolepsy started.FindingsVaccination coverage in the cohort was 75%. Of the 67 confirmed cases of narcolepsy, 46 vaccinated and 7 unvaccinated were included in the primary analysis. The incidence of narcolepsy was 9.0 in the vaccinated as compared to 0.7/100,000 person years in the unvaccinated individuals, the rate ratio being 12.7 (95% confidence interval 6.1–30.8). The vaccine-attributable risk of developing narcolepsy was 1∶16,000 vaccinated 4 to 19-year-olds (95% confidence interval 1∶13,000–1∶21,000).ConclusionsPandemrix vaccine contributed to the onset of narcolepsy among those 4 to 19 years old during the pandemic influenza in 2009–2010 in Finland. Further studies are needed to determine whether this observation exists in other populations and to elucidate potential underlying immunological mechanism. The role of the adjuvant in particular warrants further research before drawing conclusions about the use of adjuvanted pandemic vaccines in the future.

Sodium oxybate in the treatment of childhood narcolepsy–cataplexy: A retrospective study

To evaluate the efficacy and side effect profile of sodium oxybate in the treatment for narcolepsy-cataplexy in the pediatric age group. A retrospective study was conducted on 15 children and adolescents with narcolepsy-cataplexy who had been treated with sodium oxybate. The mean age at diagnosis of narcolepsy was 11 years (range 3-17 years). Subjects were followed for 3-90 months (mean 33) after starting sodium oxybate. During this period of time they were also maintained on other medications for sleepiness (n=14) and cataplexy (n=6). The charts were reviewed for documentation of improvement in sleepiness or cataplexy, side effects, and functioning in daily life. Subsequent to the addition of sodium oxybate, sleepiness improved in 13/15 patients. In patients who had Epworth Sleepiness Scale (ESS) assessments, the score fell from a baseline median of 18 to 12 (n=10, p=0.01). The number of cataplexy episodes estimated by parents decreased from a median of 38/week pre-treatment to <1/week post treatment (n=14, p<0.001). Cataplexy severity, measured on an arbitrary scale, fell from a median of 3 (severe) to 1 (mild) in all 15 subjects (p<0.001). Two of the 15 patients (13%) discontinued sodium oxybate, one for insurance reasons and the other due to constipation and dissociative feelings. A third patient stopped the medication temporarily due to body aches and dizziness, but then resumed treatment without recurrence of symptoms. Side effects in four others included tremor, blurring of vision, nocturnal awakenings, and increased nightmares. Overall, side effects occurred in 6/15 (40%) individuals. Improvement in social/academic spheres was noted in 11/15 (73%) subjects after starting sodium oxybate. The median BMI before and after treatment remained unchanged at 23 (n=14, p=0.99). Median values of height and weight before and after treatment also did not change significantly. The mean dose of sodium oxybate was 5 ± 2 g. Dose escalation owing to development of tolerance was not encountered. Sodium oxybate is effective in alleviating sleepiness and cataplexy in childhood onset narcolepsy-cataplexy. The therapeutic response was sustained over time, and without development of tolerance. Forty percent of the subjects experienced adverse effects.

Development of Parkinson’s disease in patients with Narcolepsy

Although amphetamine drugs can damage dopaminergic axons, it is unknown whether chronic treatment with amphetamine increases the risk of developing Parkinson's disease (PD). Of 1,152 consecutive PD patients, 3 had a prior diagnosis of narcolepsy. This rate is five times higher than expected (p = 0.02). These patients had typical onset of narcolepsy and underwent treatment with amphetamine. Although preliminary, this observation raises the possibility that some factors intrinsic to narcolepsy or its treatment may be a risk factor for PD.

Narcolepsy and sleep‐disordered breathing

There is a high incidence of sleep-disordered breathing (SDB) in narcoleptic patients. Some narcoleptics with SDB may benefit from treatment with continuous positive airway pressure therapy (CPAP). The aim of this study was to examine the prevalence of SDB in narcoleptics referred to a tertiary sleep disorders clinic and assess the effectiveness of CPAP as adjunctive therapy. A retrospective review of patients meeting ICSD-2 criteria for the diagnosis of narcolepsy from 2000 to 2009. One hundred and two patients (61 women) with narcolepsy were included in the study. Twenty-nine (29) patients (eight women, 21 men) were diagnosed with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) of whom 26 commenced CPAP therapy with 11 patients concurrently treated with stimulants. Patients with narcolepsy and OSAHS were older (P = 0.009) and heavier (BMI, 29.6 ± 4.8 vs. 27.3 ± 6, P = 0.042), but their ESS did not differ from patients with narcolepsy alone. Patients treated with both CPAP and stimulants were younger (P = 0.008) and less obese (BMI, 29.1 ± 4.6 vs. 30.4 ± 5.4, P = 0.044) with higher apnoea-hypopnoea index (36.15 ± 21.9 vs. 31.5 ± 16.7, P = 0.03) than those treated with CPAP alone. The ESS of CPAP-treated patients improved during follow-up (19 ± 3.6 vs. 15.8 ± 4.5, P = 0.006), but BMI increased (30.6 ± 5 vs. 31.7 ± 5.6, P = 0.05). The use of stimulants did not seem to improve on the effectiveness of CPAP. Coexisting SDB is common in narcoleptics (28.5%). CPAP therapy in narcoleptics with OSAHS remains a useful second-line adjunct to standard therapy.

Testing sleepiness and vigilance in the sleep laboratory

Excessive daytime sleepiness (EDS) is common and a potentially devastating public health challenge. EDS has been implicated as a contributing factor to workplace injury, motor vehicle accidents, cardiovascular disease, and impaired quality of life. Subjective self-report measures have failed to sufficiently quantify EDS. The use of objective tools found in sleep laboratories is therefore fundamental in the management of patients with EDS. The purpose of this review is to provide an overview of the current methods used to quantify sleepiness, and to highlight recent advances. The Multiple Sleep Latency Test (MSLT), normally used for the diagnosis of narcolepsy, can be a useful tool in recognizing other forms of sleepiness. The Maintenance of Wakefulness Test (MWT) has also been confirmed as an important test to identify EDS, as well as to provide an indicator of future risk of accidents. Modifications and newer tests have been discussed with potential applications for the future. Objective tests such as the MSLT and MWT are useful in the diagnosis and management of patients with EDS. However, the relatively high cost can restrict their overall usefulness in clinical medicine. Newer simple tests are under development.

Nocturnal polysomnographic characteristics of pediatric narcolepsy

The aim of this study was to describe the polysomnographic features of childhood-onset narcolepsy. A retrospective review was performed on children with narcolepsy. The polysomnogram findings were compared with reference values obtained from normative data in the general population. Narcolepsy subjects had a mean initial sleep latency of 10.9 min on nocturnal PSG, which was shorter by a mean of 18 min than corresponding values from normative data (P < 0.001). Short initial REM latency on nocturnal PSG correlated with the number of SOREMPs on MSLT in subjects with narcolepsy (P = 0.007). These findings may assist in the clinical diagnosis of narcolepsy.

Benefit of Repeat Multiple Sleep Latency Testing in Confirming a Possible Narcolepsy Diagnosis

The clinical diagnosis of narcolepsy is usually uncomplicated in the presence of cataplexy. Objective testing is more important in ambiguous disease. The gold-standard objective test in these cases is the multiple sleep latency test (MSLT). Repeat testing can be burdensome but is reasonable when faced with a diagnostic dilemma. However, there is limited evidence to support this approach. In this study, we assessed the diagnostic utility of a repeat MSLT in patients suspected of narcolepsy whose first MSLT result was nonconfirmatory. Of 125 patients who underwent an MSLT between 2004 and 2009, we identified 10 (9.6%) who had undergone repeat studies. We analyzed changes in MSLT parameters while taking account of other relevant differences between testing. Two patients (20%) met narcolepsy criteria during the second MSLT. Nine patients (90%) met sleepiness criteria (mean sleep latency <8 minutes) during the second MSLT while only 5 did during the first (P = 0.05). We demonstrate that a repeat MSLT confirmed the diagnosis of narcolepsy in 20% of patients whose results had been nonconfirmatory on a first MSLT. This study provides support for a repeat MSLT in cases where clinical suspicion for narcolepsy is high despite an ambiguous first test.

Recent Advances in the Treatment of Narcolepsy

A diagnosis of narcolepsy requires pharmacologic treatment in more than 90% of patients. Wake-promoting compounds are used to treat excessive daytime sleepiness (EDS), and anticataplectics are used for cataplexy. The treatment of EDS includes the use of amphetamine-like CNS stimulants (such as dextroamphetamine and methylphenidate), modafinil, and its R-enantiomer, armodafinil. Because of its high safety and low side-effect profiles, modafinil has become the first-line treatment of choice for EDS associated with narcolepsy. However, wake-promoting compounds do not improve cataplexy and dissociated manifestation of REM sleep, and so antidepressants (monoamine uptake inhibitors) are additionally used for the treatment of cataplexy and REM sleep abnormalities. Tricyclic antidepressants potently reduce REM sleep and thus have been used for the treatment of cataplexy and REM sleep abnormalities, but these have recently been replaced by more selective serotonin and/or noradrenaline uptake inhibitors with better side-effect profiles. As sodium oxybate (the approved formula of γ-hydroxybutyrate in the United States), given at night, improves both EDS and cataplexy, the number of US patients treated with sodium oxybate is increasing, while much progress has been made in understanding the modes of action of amphetamine-like CNS stimulants.

Wake-REM sleep transitions for measuring REM sleep disturbance: Comparison between narcolepsy, idiopathic hypersomnia and healthy controls

This study tested a well-known but as yet nonoperationalized means for measuring REM sleep disturbance in patients with narcolepsy at night. We retrospectively analyzed polysomnographies of patients with narcolepsy with cataplexy (n = 18), narcolepsy without cataplexy (n = 12), idiopathic hypersomnia (n = 22) and healthy controls (n = 33) with regard to the number of wake-REM sleep transitions as a measurement for REM sleep disturbance at night. We found a significantly higher number of transitions between wake and REM sleep (14.17 ± 2.00) in patients with narcolepsy with cataplexy than in healthy controls (3.70 ± 1.00; p lt; 0.001) and patients with idiopathic hypersomnia (5.36 ± 1.00; p = 0.001). These results confirm previous findings that REM sleep disturbance is a specific phenomenon for narcolepsy with cataplexy. Additionally we found that wake-REM sleep transitions provide a useful marker for operationalizing and measuring this sleep disturbance. A possible mediating factor for this observation is the hypocretin-1 system, which is deficient in narcolepsy with cataplexy but intact in idiopathic hypersomnia. The number of wake-REM sleep transitions may thus become a useful additional means for the differential diagnosis of narcolepsy.

Évaluation d’une somnolence diurne excessive en psychopathologie de l’enfant et de l’adolescent

Childhood and adolescence are characterized by major changes in physiological, social and psychological domains. Some learning, behavior, mood or sleep disorders occurring during these ever-changing periods may lead children and teenagers to search for psychiatric care. It is then crucial to accurately determine which symptoms pertain to sleep and alertness disorders. Otherwise, some sleepy children and adolescents may be incorrectly considered as lazy, hyperactive or depressed. The evaluation of sleepiness requires a thorough physical examination (including the otorhinolaryngologic aspect), the completion of scales and brief questionnaires suited for pediatric patients, a fully completed sleep diary and in some cases biological or electrophysiological exams such as polysomnography (suited for the diagnosis of sleep apnea, narcolepsy, and periodic limb movement disorder). These investigations will help recognize excessive sleepiness, evaluate the often bi-directional links with the associated psychopathology and, should the case arise, diagnose primary sleep disorders (mostly sleep apnea in children and insufficient sleep in adolescents) and guide the adequate treatment.

Narcolepsy due to Parkinson's disease with a decrease in cerebrospinal-fluid orexin: a case report

A 57-year old man became affected by excessive daytime sleepiness. Thereafter, he had difficulty in moving his left limbs and began to walk slowly. He had no particular past or family history. He had taken no medications. Neurologically, Parkinsonism was present. Sleep examinations revealed that the diagnostic criteria of narcolepsy without cataplexy were fulfilled. The orexin level in the cerebrospinal fluid (CSF) was undetectable (>40 pg/mL). HLA DR2 was negative. These factors led to a diagnosis of narcolepsy due to Parkinson’s disease (PD). This is the first clear case of narcolepsy due to PD presenting a decreased CSF-orexin level.

Abnormally Low Serum Acylcarnitine Levels in Narcolepsy Patients

Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness, cataplexy, and REM sleep abnormalities. A genome-wide association study identified a novel narcolepsy-related single nucleotide polymorphism (SNP), rs5770917, which is located adjacent to CPT1B (carnitine palmitoyltransferase 1B). In this study, we analyzed the CPT1B expression level and measured the carnitine fractions in blood samples obtained from narcolepsy patients and control subjects to test the hypothesis that fatty acid β-oxidation is altered in narcolepsy. We measured CPT1B mRNA expression in white blood cells of 38 narcolepsy patients and 56 healthy control subjects. The serum carnitine fractions (total carnitine, free carnitine, and acylcarnitine) were measured in the 38 narcolepsy patients and in 30 of 56 control subjects. Stepwise multiple regression analysis revealed that the risk allele (C) for SNP rs5770917 was significantly associated with decreased CPT1B mRNA expression (P = 1.0 × 10(-9)), and the CPT1B expression was higher in the narcolepsy patients than in the controls (P = 0.005). The acylcarnitine levels were abnormally low in 21% of the narcolepsy patients while those of all the controls were within the normal range. Stepwise multiple regression analysis using the dichotomous variable for acylcarnitine (normal or abnormal) as an objective variable revealed that the diagnosis of narcolepsy but not CPT1B expression level and BMI was associated with abnormally low acylcarnitine levels (P = 0.006). Our results indicate that multiple factors are involved in the regulation of serum acylcarnitine levels. Abnormally low levels of acylcarnitine observed in narcolepsy suggest dysfunctional fatty acid β-oxidation pathway.

P03-394 - Quantitative electrophysiology during night- and daytime including electroencephalography and event-related potential EEG/ERP topography and tomography (LORETA) in hyperthyroidism

IntroductionIn contrast to the abundance of visual qualitative EEG reports in patho-endocrinology, there is a paucity of quantitative EEG findings.ObjectivesElectrophysiology may be utilized for differential diagnosis of hypersomnolence.AimsTo investigate long-term daytime sleepiness in a young female neurologist with the tentative diagnosis of narcolepsy in addition to moderate depression/anxiety and congenital thyroid hypoplasia treated with thyroxin.MethodsThree-night polysomnography, multiple sleep latency test (MSLT), visual EEG/ERP-mapping, LORETA, psychometrics and blood analyses were performed.ResultsPolysomnography revealed normal sleep efficiency and sleep architecture, but a high arousal index of up to 63/h TST. The MSLT showed a shortened mean sleep latency of 3.7 min. without REM-sleep onsets, objectifying the high Epworth Sleepiness score of 18. Visual EEG evaluation exhibited a fast alpha rhythm with intermittent theta and delta intrusions and paroxysmal activities. EEG-mapping showed an accelerated dominant frequency and ubiquitous increase in absolute (especially delta and beta) power, ERP revealed shortened N1 latency and very high amplitudes in all components (P300 &gt; 5 SD). LORETA demonstrated significant regional increases in delta, alpha-2 and beta-1 power in the anterior cingulate, orbital, ventromedial, dorsolateral prefrontal cortex and temporal cortex, predominantly right hemispherically. Psychometry showed increased anxiety (SAS) and depression (SDS) and reduced quality of life. Finally, hormonal analysis pointed to thyrotoxicosis factitia (ICD-10 E05.4).ConclusionDiagnostic investigations clearly elucidated the pathogenesis of the presenting diagnosis of organic hypersomnia triggered by increased sleep-microarousals due to thyrotoxicosis factitia. Discontinuation of hormone substitution led to a normalization process that will be discussed.

Narcolepsy: a review

Narcolepsy is a lifelong sleep disorder characterized by a classic tetrad of excessive daytime sleepiness with irresistible sleep attacks, cataplexy (sudden bilateral loss of muscle tone), hypnagogic hallucination, and sleep paralysis. There are two distinct groups of patients, ie, those having narcolepsy with cataplexy and those having narcolepsy without cataplexy. Narcolepsy affects 0.05% of the population. It has a negative effect on the quality of life of its sufferers and can restrict them from certain careers and activities. There have been advances in the understanding of the pathogenesis of narcolepsy. It is thought that narcolepsy with cataplexy is secondary to loss of hypothalamic hypocretin neurons in those genetically predisposed to the disorder by possession of human leukocyte antigen DQB1*0602. The diagnostic criteria for narcolepsy are based on symptoms, laboratory sleep tests, and serum levels of hypocretin. There is no cure for narcolepsy, and the present mainstay of treatment is pharmacological treatment along with lifestyle changes. Some novel treatments are also being developed and tried. This article critically appraises the evidence for diagnosis and treatment of narcolepsy.

Pseudocataplexy and Transient Functional Paralysis: A Spectrum of Psychogenic Motor Disorder

Pseudocataplexy and Transient Functional Paralysis: A Spectrum of Psychogenic Motor Disorder

Diagnosing narcolepsy with cataplexy on history alone: challenging the International Classification of Sleep Disorders (ICSD-2) criteria

The second version of the International Classification of Sleep Disorders suggests narcolepsy with cataplexy can be diagnosed on history alone. Five patients with a history supportive of narcolepsy/cataplexy. Case review following clinical investigation. None of the five patients had a diagnosis of narcolepsy/cataplexy on the basis of objective testing using polysomnography (PSG) and multiple sleep latency testing (MSLT). PSG and MSLT should always be used in conjunction with a comprehensive history taken by an experienced sleep physician to support a diagnosis of narcolepsy with cataplexy and to exclude other conditions that may mimic narcolepsy.