Sexual excitation induces courtship ultrasonic vocalizations and cataplexy-like behavior in orexin neuron-ablated male mice.

Cataplexy is triggered by laughter in humans and palatable food in mice. To further evaluate mice's cataplexy, we examined courtship behavior in orexin neuron-ablated mice (ORX-AB), one of the animal models of narcolepsy/cataplexy. Wild-type female mice were placed into the home cage of male ORX-AB and cataplexy-like behavior was observed along with ultrasonic vocalizations (USVs), also known as the "love song". ORX-AB with a female encounter showed cataplexy-like behavior both during the dark and light periods, whereas ORX-AB with chocolate predominantly showed it during the dark period. During the light period observation, more than 85% of cataplexy-like bouts were preceded by USVs. A strong positive correlation was observed between the number of USVs and cataplexy-like bouts. Cataplexy-like behavior in narcoleptic mice is a good behavioral measure to study the brain mechanisms behind positive emotion because they can be induced by different kinds of positive stimuli, including chocolate and female courtship.

Neuropsychological Alterations in Narcolepsy with Cataplexy and the Expression of Cognitive Deficits.

OBJECTIVES: The objective of our study was to assess attention processes and executive function in patients with narcolepsy with cataplexy (NT1). To do so, we compared the results with those of a control group from the general population using an extensive neuropsychological test battery. METHODS: We studied 28 patients with NT1 and 28 healthy control participants matched for age, gender, and educational level. They all completed questionnaires on sleepiness, anxiety, and depression symptoms. In addition, they underwent neuropsychological tests. The ability to maintain attention was assessed using three computer tasks with different levels of complexity. RESULTS: Patients had significantly more daytime sleepiness than controls. A significant negative correlation between depression and disease duration was found in NT1 patients. The results of the anxiety questionnaire correlated with the presence of sleep paralysis. There were significant differences in information processing speed subtasks. Patients made significantly more omissions and generally reacted slower and more variably than controls in computerized tasks. As for executive function, patients performed worse in phonologic fluency tasks than controls. However, when the influence of processing speed on fluency tasks was statistically controlled, part of this significant difference disappeared. CONCLUSIONS: Our results indicate that the negative correlation between depression and disease duration probably reflects progressive adaptation to the functional burden of the disease. Information processing speed plays a fundamental role in the expression of cognitive deficits. We emphasized the need to control the influence of processing speed and sustained attention in the neuropsychological assessment of NT1 patients.

Narcolepsy and emotional experience: a review of the literature.

Narcolepsy is a chronic sleep disorder characterized by excessive daytime sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis. This disease affects significantly the overall patient functioning, interfering with social, work, and affective life. Some symptoms of narcolepsy depend on emotional stimuli; for instance, cataplectic attacks can be triggered by emotional inputs such as laughing, joking, a pleasant surprise, and also anger. Neurophysiological and neurochemical findings suggest the involvement of emotional brain circuits in the physiopathology of cataplexy, which seems to depending on the dysfunctional interplay between the hypothalamus and the amygdala associated with an alteration of hypocretin levels. Furthermore, behavioral studies suggest an impairment of emotions processing in narcolepsy-cataplexy (NC), like a probable coping strategy to avoid or reduce the frequency of cataplexy attacks. Consistently, NC patients seem to use coping strategies even during their sleep, avoiding unpleasant mental sleep activity through lucid dreaming. Interestingly, NC patients, even during sleep, have a different emotional experience than healthy subjects, with more vivid, bizarre, and frightening dreams. Notwithstanding this evidence, the relationship between emotion and narcolepsy is poorly investigated. This review aims to provide a synthesis of behavioral, neurophysiological, and neurochemical evidence to discuss the complex relationship between NC and emotional experience and to direct future research.

[Neuropsychological alterations in narcolepsy with cataplexy: a review]. / Alteraciones neuropsicologicas en la narcolepsia con cataplejia: una revision.

AIM: To describe the current state of the art about the main cognitive deficits that appear in patients affected with narcolepsy with cataplexy (NT1). DEVELOPMENT: The majority of the studies have found that the most impaired cognitive functions are attention (especially maintenance of attention or sustained attention), speed of information processing and executive functions (in particular, verbal fluency and resistance to the stimuli interference). These data indicate the difficulty to use the available cognitive resources of the patient. These alterations are similar to those present in other hypersomnias, although they might differ in intensity. Moreover, most of the studies emphasize a high prevalence of different depressive and anxious disorders. It has been suggested that predisposition to anxiety could be part of the characteristic phenotype of these patients. Anxiety could act either as a trigger for the disease or a consequence of the disease. CONCLUSIONS: Cognitive deficits in patients with NT1 appear in long lasting and/or monotonous tasks and in high cognitive demanding tasks. The presence of depressive symptomatology, together with excessive daytime sleepiness in these patients could affect their performance in neuropsychological test, and it might be related to their subjective perception of the cognitive deficits.

TITLE: Alteraciones neuropsicologicas en la narcolepsia con cataplejia: una revision.Objetivo. Describir el estado actual de conocimiento sobre los principales deficits cognitivos que presentan los pacientes con narcolepsia con cataplejia o narcolepsia de tipo 1. Desarrollo. La mayoria de los estudios ha encontrado que las funciones cognitivas mas afectadas son la atencion (especialmente el mantenimiento de la atencion o atencion sostenida), la velocidad de procesamiento de la informacion y las funciones ejecutivas (en particular, la fluidez verbal y la resistencia a la interferencia de estimulos). Estos datos indican una dificultad para utilizar los recursos cognitivos de los que dispone el sujeto. Estas alteraciones son similares a las presentes en otras hipersomnias, aunque difieren en la intensidad. Por otra parte, la mayoria de los estudios destaca una elevada prevalencia de diferentes trastornos depresivos y ansiosos. Se ha sugerido que la predisposicion a la ansiedad forma parte del fenotipo caracteristico de estos pacientes. La ansiedad podria actuar como un factor desencadenante de la enfermedad y ser asimismo una consecuencia de la enfermedad. Conclusiones. Los deficits cognitivos en los pacientes con narcolepsia de tipo 1 se manifiestan en tareas de larga duracion o monotonas y en tareas con alta demanda cognitiva, principalmente en tareas de atencion sostenida. La presencia de sintomatologia depresiva en estos pacientes, junto con la excesiva somnolencia diurna, parecen afectar a su rendimiento en las pruebas neuropsicologicas, y estar estrechamente relacionadas con la apreciacion subjetiva de dificultades cognitivas.

High Rates of Psychiatric Comorbidity in Narcolepsy: Findings From the Burden of Narcolepsy Disease (BOND) Study of 9,312 Patients in the United States.

OBJECTIVE: To evaluate psychiatric comorbidity patterns in patients with a narcolepsy diagnosis in the United States. METHODS: Truven Health Analytics MarketScan Research Databases were accessed to identify individuals ≥ 18 years of age with ≥ 1 ICD-9 diagnosis code(s) for narcolepsy continuously insured between 2006 and 2010 and non-narcolepsy controls matched 5:1 (age, gender, region, payer). Extensive subanalyses were conducted to confirm the validity of narcolepsy definitions. Narcolepsy subjects and controls were compared for frequency of psychiatric comorbid conditions (based on ICD-9 codes/Clinical Classification Software [CCS] level 2 categories) and psychiatric medication use. RESULTS: The final population included 9,312 narcolepsy subjects and 46,559 controls (each group, mean age = 46.1 years; 59% female). All categories of mental illness were significantly more prevalent in patients with narcolepsy versus controls, with the highest excess prevalence noted for CCS 5.8 Mood disorders (37.9% vs 13.8%; odds ratio [OR] = 4.0; 95% CI, 3.8-4.2), CCS 5.8.2 Depressive disorders (35.8% vs 13.0%; OR = 3.9; 95% CI, 3.7-4.1), and CCS 5.2 Anxiety disorders (25.1% vs 11.9%; OR = 2.5; 95% CI, 2.4-2.7). Excess prevalence of anxiety and mood disorders (narcolepsy vs controls) was higher in younger age groups versus older age groups. Psychiatric medication usage was higher in the narcolepsy group versus controls in the following categories: selective serotonin reuptake inhibitors (36% vs 17%), anxiolytic benzodiazepines (34% vs 19%), hypnotics (29% vs 13%), serotonin-norepinephrine reuptake inhibitors (21% vs 6%), and tricyclic antidepressants (13% vs 4%) (all P values < .0001). CONCLUSIONS: Narcolepsy is associated with significant comorbid psychiatric illness burden and higher psychiatric medication usage compared with the non-narcolepsy population.

[A case of narcolepsy in adolescent].

A description of the clinical observation of the teenager with narcolepsy is presented. This case demonstrates specific clinical and polysomnographic characteristics of narcolepsy with cataplexy as well as a unique combination of paroxysmal forms of diseases affecting the state of sleep and wakefulness (narcolepsy, epilepsy and other phenomena related to sleep medicine). These forms include sleep-associated eating disorder and restless legs syndrome. The current approaches to treatment of narcolepsy are presented.

Morphological alterations in amygdalo-hippocampal substructures in narcolepsy patients with cataplexy.

Although the role of hypocretin-mediated amygdalo-hippocampal dysfunction is hypothesized to be linked with narcolepsy, there have been no human MRI studies investigating the relationship between their regional volume and key symptoms of narcolepsy. To investigate the morphological changes of amygdalo-hippocampus and its relationship with clinical features in patients with narcolepsy, point-wise morphometry that allowed for measuring the regional volumes of amygdalo-hippocampus on T1-weighted MRI was applied. Participants were 33 drug-naïve patients and 35 age-/gender-matched controls (mean ± SD: 27 ± 6 years). We compared hippocampal and amygdalar subfields volumes between patients and controls and correlated between volume and clinical and neuropsychological features in patients. Bilateral hippocampal atrophy (183 vertices) was identified mainly located within the CA1 subfield (FDR < 0.05). Significant amygdalar volume reduction was found in the areas of the centromedial (102 vertices) and laterobasal nuclear groups (LB, 35 vertices). There was no volume increase in patients relative to controls (FDR >0.2). After controlling depressive mood, sleep quality, age, and gender, hippocampal CA1 atrophy and amygdalar centromedial atrophy were associated with longer duration of daytime sleepiness and shorter mean REM sleep latency (|r| >0.44, p < 0.01). The amygdalar centromedial atrophy was associated with longer duration of cataplexy (|r| >0.47, p < 0.005). Subfields atrophy of amygdalo-hippocampus in untreated patients with narcolepsy that was found relative to controls suggests that CA1 of the hippocampus and centromedial area of amygdala are closely related to the severity of narcolepsy and play a crucial role in the circuitry of cataplexy.

Attention-Deficit/Hyperactivity Disorder (ADHD) Symptoms in Pediatric Narcolepsy: A Cross-Sectional Study.

STUDY OBJECTIVES: To evaluate the frequency, severity, and associations of symptoms of attention-deficit/hyperactivity disorder (ADHD) in children with narcolepsy with and without cataplexy. DESIGN: Cross-sectional survey. SETTINGS: Four French national reference centers for narcolepsy. PATIENTS: One hundred eight consecutively referred children aged younger than 18 y with narcolepsy, with (NwC, n = 86) or without cataplexy (NwoC, n = 22), and 67 healthy controls. INTERVENTIONS: The participants, their families, and sleep specialists completed a structured interview and questionnaires about sleep, daytime sleepiness, fatigue, and ADHD symptoms (ADHD-rating scale based upon Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision [DSM-IV-TR] symptoms), and use of psychostimulants for the treatment of narcolepsy (administered in 68.2%). Polysomnographic measures were collected. MEASUREMENTS AND RESULTS: Clinically significant levels of ADHD symptoms were found in 4.8% of controls compared with 35.3% in patients with NwoC (P < 0.001) and 19.7% in patients with NwC (P < 0.01). Total ADHD scores were 6.4 (95% confidence interval [CI]: 4.5, 9.0) in controls compared with 14.2 (95% CI: 10.6, 18.9; P < 0.001), in patients with NwoC and 12.2 (95% CI: 9.8, 15.3; P < 0.01) in patients with NwC; subscores of inattention and hyperactivity/impulsivity were also significantly higher in both narcolepsy groups compared with controls. No difference was found between the NwC and NwoC groups for any ADHD measure. ADHD symptom severity was associated with increased levels of sleepiness, fatigue, and insomnia. Compared with the 34 untreated patients, the 73 patients treated with psychostimulants (modafinil in 91%) showed a trend toward lower narcolepsy symptoms but not lower ADHD symptoms. CONCLUSIONS: Pediatric patients with narcolepsy have high levels of treatment-resistant attention-deficit/hyperactivity disorder (ADHD) symptoms. The optimal treatment for ADHD symptoms in these patients warrants further evaluation in longitudinal intervention studies.

Comparing Treatment Effect Measurements in Narcolepsy: The Sustained Attention to Response Task, Epworth Sleepiness Scale and Maintenance of Wakefulness Test.

STUDY OBJECTIVES: To validate the Sustained Attention to Response Task (SART) as a treatment effect measure in narcolepsy, and to compare the SART with the Maintenance of Wakefulness Test (MWT) and the Epworth Sleepiness Scale (ESS). DESIGN: Validation of treatment effect measurements within a randomized controlled trial (RCT). PATIENTS: Ninety-five patients with narcolepsy with or without cataplexy. INTERVENTIONS: The RCT comprised a double-blind, parallel-group, multicenter trial comparing the effects of 8-w treatments with pitolisant (BF2.649), modafinil, or placebo (NCT01067222). MWT, ESS, and SART were administered at baseline and after an 8-w treatment period. The severity of excessive daytime sleepiness and cataplexy was also assessed using the Clinical Global Impression scale (CGI-C). MEASUREMENTS AND RESULTS: The SART, MWT, and ESS all had good reliability, obtained for the SART and MWT using two to three sessions in 1 day. The ability to distinguish responders from nonresponders, classified using the CGI-C score, was high for all measures, with a high performance for the SART (r = 0.61) and the ESS (r = 0.54). CONCLUSIONS: The Sustained Attention to Response Task is a valid and easy-to-administer measure to assess treatment effects in narcolepsy, enhanced by combining it with the Epworth Sleepiness Scale.

A 12-week open-label, multicenter study evaluating the safety and patient-reported efficacy of sodium oxybate in patients with narcolepsy and cataplexy.

OBJECTIVE: This study aimed to evaluate safety and efficacy of sodium oxybate (SXB) titrated to effect. METHODS: SXB-naive patients who had participated in a randomized SXB clinical trial and had not been titrated to adequate clinical effect were initiated on open-label SXB at 4.5 g/night and titrated in 1.5-g increments to 6, 7.5, or 9 g/night or down to 3 g/night, based on individual clinical response. Treatment was 12 weeks; safety was the primary outcome. Efficacy was evaluated using the Narcolepsy Symptom Assessment Questionnaire (NSAQ), a five-point scale ("much improved" to "much worse") that assessed changes from baseline in specific symptoms. Response was defined as "much improved" or "somewhat improved" overall at weeks 6 and 12. RESULTS: Of 202 patients, 171 (85%) completed treatment; final doses were 3 g (n = 5), 4.5 g (n = 29), 6 g (n = 80), 7.5 g (n = 66), and 9 g (n = 22). Adverse events (AEs) were reported in 114 patients (56%), serious AEs in five (2%). The most common AEs were nausea (10%), headache (7%), and dizziness (5%). Response rate was 92% at week 6 and 90% at week 12; most patients reported improvements in all individual symptoms. Overall, 60% of patients rated their symptoms at 12 weeks as "much improved," and this improvement was dose dependent. CONCLUSIONS: The SXB safety profile was consistent with parent trials. Ninety percent of patients reported improvements as measured by the NSAQ.

Narcolepsy goes to school: the three Rs for school nurses.

The sleep disorder narcolepsy most often first appears in the teen years. It can dash the dreams of optimistic, intelligent students. It can make some students the target of nasty jokes and bullying, leaving them depressed and socially isolated. It can challenge children's self-esteem, and lowered self-esteem may last a lifetime. Typically, children with narcolepsy gain weight and have no interest in participating in anything. Many constantly feel extreme tiredness, and they may experience cataplexy. School nurses and teachers can help if they know the symptoms and practice the 3 Rs of narcolepsy: Recognize the symptoms of narcolepsy; Respect that narcolepsy is a lifelong, serious sleep disorder that needs treatment; and Refer students who exhibit symptoms to medical professionals. The 3 Rs will help students living with this lifelong disorder to get a fair shake in life's academic, social, and career arenas.

Facing emotions in narcolepsy with cataplexy: haemodynamic and behavioural responses during emotional stimulation.

Narcolepsy with cataplexy is a complex sleep disorder that affects the modulation of emotions: cataplexy, the key symptom of narcolepsy, is indeed strongly linked with emotions that usually trigger the episodes. Our study aimed to investigate haemodynamic and behavioural responses during emotional stimulation in narco-cataplexy. Twelve adult drug-naive narcoleptic patients (five males; age: 33.3 ± 9.4 years) and 12 healthy controls (five males; age: 30.9 ± 9.5 years) were exposed to emotional stimuli (pleasant, unpleasant and neutral pictures). Heart rate, arterial blood pressure and mean cerebral blood flow velocity of the middle cerebral arteries were continuously recorded using photoplethysmography and Doppler ultrasound. Ratings of valence and arousal and coping strategies were scored by the Self-Assessment Manikin and by questionnaires, respectively. Narcoleptic patients' haemodynamic responses to pictures overlapped with the data obtained from controls: decrease of heart rate and increase of mean cerebral blood flow velocity regardless of pictures' content, increase of systolic blood pressure during the pleasant condition, and relative reduction of heart rate during pleasant and unpleasant conditions. However, when compared with controls, narcoleptic patients reported lower arousal scores during the pleasant and neutral stimulation, and lower valence scores during the pleasant condition, respectively, and also a lower score at the 'focus on and venting of emotions' dimensions of coping. Our results suggested that adult narcoleptic patients, compared with healthy controls, inhibited their emotion-expressive behaviour to emotional stimulation, and that may be related to the development of adaptive cognitive strategies to face emotions avoiding cataplexy.

Neuropsychological findings in childhood narcolepsy.

Narcolepsy with cataplexy is a severely disabling disorder very often arising in childhood. Data on neuropsychological impairment in children are scant. We administered standardized neuropsychological tests to 13 children with narcolepsy with cataplexy. Overall, our patients displayed multiple patterns of cognitive and behavioral dysfunction, and often academic failure (7 cases out of 13). All children had a normal full intelligence quotient (IQ), but 3 patients presented a significantly higher and 2 a significantly lower Verbal IQ compared to Performance IQ, respectively. Mean sleep latency was significantly correlated (P < .05) to alertness functions. Eight patients displayed behavioral problems: emotional symptoms and conduct problems prevailed. Childhood narcolepsy with cataplexy represents a risk factor for subtle and heterogeneous cognitive impairments potentially resulting in academic failure, despite the normal IQ. These children also have a certain psychopathological risk. All this seems to be at least partially detached from the direct effects of daytime sleepiness.

Impact of obesity in children with narcolepsy.

AIMS: To evaluate the impact of obesity on clinical and sleep characteristics in a population of narcoleptic children. METHODS: Data from the children diagnosed with idiopathic narcolepsy in the National Reference Centers for Narcolepsy were collected between 2008 and 2011. Clinical and electrophysiological characteristics were compared between obese (body mass index [BMI] greater than P97) and nonobese children. RESULTS: The 117 children (65 boys, 59 de novo patients) had a mean age of 11.6 ± 3.1 years on diagnosis. Cataplexy was present in 81%, DQB1*0602 in 91%. Mean BMI was 23.2 ± 5.2 kg/m(2) and BMI z-score was 2.9 ± 2.6. Obesity was found in 60% with a similar prevalence in treated versus de novo patients and in patients with and without cataplexy. Sleepiness and cataplexy started earlier in obese children. Obese narcoleptic children had lower sleep efficiency, higher apnea hypopnea index and respiratory arousals index (RAI) than nonobese children. BMI z-score was positively correlated with RAI. Obese children were more tired and missed more often school than nonobese children. CONCLUSION: Obesity affects more than 50% of narcoleptic children, mostly younger at disease onset, and has a deleterious impact on sleep quality as well as on school attendance.

Clinical, polysomnographic and genome-wide association analyses of narcolepsy with cataplexy: a European Narcolepsy Network study.

The aim of this study was to describe the clinical and PSG characteristics of narcolepsy with cataplexy and their genetic predisposition by using the retrospective patient database of the European Narcolepsy Network (EU-NN). We have analysed retrospective data of 1099 patients with narcolepsy diagnosed according to International Classification of Sleep Disorders-2. Demographic and clinical characteristics, polysomnography and multiple sleep latency test data, hypocretin-1 levels, and genome-wide genotypes were available. We found a significantly lower age at sleepiness onset (men versus women: 23.74 ± 12.43 versus 21.49 ± 11.83, P = 0.003) and longer diagnostic delay in women (men versus women: 13.82 ± 13.79 versus 15.62 ± 14.94, P = 0.044). The mean diagnostic delay was 14.63 ± 14.31 years, and longer delay was associated with higher body mass index. The best predictors of short diagnostic delay were young age at diagnosis, cataplexy as the first symptom and higher frequency of cataplexy attacks. The mean multiple sleep latency negatively correlated with Epworth Sleepiness Scale (ESS) and with the number of sleep-onset rapid eye movement periods (SOREMPs), but none of the polysomnographic variables was associated with subjective or objective measures of sleepiness. Variant rs2859998 in UBXN2B gene showed a strong association (P = 1.28E-07) with the age at onset of excessive daytime sleepiness, and rs12425451 near the transcription factor TEAD4 (P = 1.97E-07) with the age at onset of cataplexy. Altogether, our results indicate that the diagnostic delay remains extremely long, age and gender substantially affect symptoms, and that a genetic predisposition affects the age at onset of symptoms.

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.

Quality of life in patients with narcolepsy with cataplexy, narcolepsy without cataplexy, and idiopathic hypersomnia without long sleep time: comparison between patients on psychostimulants, drug-naïve patients and the general Japanese population.

OBJECTIVE: To assess the quality of life of patients with narcolepsy with cataplexy (NA-CA), narcolepsy without cataplexy (NA w/o CA), and idiopathic hypersomnia without long sleep time (IHS w/o LST) who were taking psychostimulant medication, and to ascertain which factors (including psychosocial and environmental variables) influence quality of life in this population. METHODS: In total, 185 patients who had received regular treatment were enrolled in the study (NA-CA, n=83; NA w/o CA, n=48; IHS w/o LST, n=54). Patients were asked to complete questionnaires including the Short Form-36 Health Survey (SF-36), the Epworth Sleepiness Scale (ESS), and items concerning psychosocial and environmental variables. RESULTS: All three diagnostic groups had significantly lower scores for most SF-36 domains compared with the Japanese normative data, and the ESS score was significantly reduced with treatment. Multiple logistic regression analyses revealed that several SF-36 domains were associated with the ESS score; autonomy in controlling own job schedule, experience of divorce or break up with a partner due to symptoms, experience of being forced to relocate or being dismissed due to symptoms, and perception of support from others. CONCLUSIONS: The severity of subjective sleepiness and psychological and environmental variables influenced quality of life in patients with these hypersomnias of central origin.

Analysis of cortical thickness in narcolepsy patients with cataplexy.

STUDY OBJECTIVES: To investigate differences in cortical thickness in narcolepsy patients with cataplexy and control subjects. DESIGN: Cortical thickness was measured using a 3-D surface-based method that enables more accurate measurement in deep sulci and localized regional mapping. SETTING: University hospital. PATIENTS AND PARTICIPANTS: We enrolled 28 patients with narcolepsy and cataplexy and 33 age-and sex-matched control subjects. INTERVENTIONS: Cortical thickness was measured using a direct method for calculating the distance between corresponding vertices from inner and outer cortical surfaces. MEASUREMENTS AND RESULTS: We normalized cortical surfaces using 2-D surface registration and performed diffusion smoothing to reduce the variability of folding patterns and to increase the power of the statistical analysis. Localized cortical thinning in narcolepsy patients with cataplexy was found in orbitofrontal gyri, dorsolateral and medial prefrontal cortexes, insula, cingulate gyri, middle and inferior temporal gyri, and inferior parietal lobule of the right and left hemispheres at the level of a false discovery rate P<0.05. No significant local increases in cortical thickness were observed in narcolepsy patients. A significant negative correlation was observed between the narcolepsy patients' scores on the Epworth Sleepiness Scale and the cortical thickness of the left supramarginal gyrus. CONCLUSIONS: Cortical thinning in narcolepsy patients with cataplexy in localized anatomic brain regions may serve as a possible neuroanatomic mechanism of the disturbances in attention, memory, emotion, and sleepiness.

Narcolepsy with cataplexy associated with nocturnal compulsive behaviors: a case-control study.

STUDY OBJECTIVES: To assess the prevalence of sleep related-eating disorder (SRED) and nocturnal smoking (NS) in patients with narcolepsy with cataplexy (NC). DESIGN: Case-control study. SETTING: University hospital. PATIENTS OR PARTICIPANTS: 65 consecutive adult NC patients (33 men; mean age 43.9 ± 19.2 years) and 65 age-, sex-, and geographical origin-matched controls. INTERVENTIONS: Validated questionnaires were used to investigate SRED, NS, restless legs syndrome (RLS), and psychopathological traits (using Eating Disorder Inventory-2 [EDI-2]; Maudsley Obsessive-Compulsive Inventory [MOCI]; and Beck Depression Inventory [BDI]). MEASUREMENTS AND RESULTS: NC patients showed a higher prevalence of SRED (32% vs 3%, P=0.00001), NS (21% vs 0%, P=0.00006), and RLS (18% vs 5%, P=0.013) than controls. Moreover, NC patients presented more frequently with an eating-related pathological profile on the EDI-2 (80% vs 46%, P=0.00006) and had a higher prevalence of depressed mood on the BDI (41% vs 18%, P=0.004). In comparison to patients without SRED, NC patients with SRED were more frequently women (71% vs 39%, P=0.013), had higher "bulimic" (29% vs 2%, P=0.004) and "social insecurity" (48% vs 18%, P=0.013) traits on the EDI-2, had higher obsessive-compulsiveness on the MOCI (29% vs 4%, P = 0.009), and were more depressed on the BDI (67% vs 29%, P=0.005). NC patients with NS showed more frequent pathological profiles on the EDI-2 (100% vs 75%, P=0.035), including the "bulimic" (29% vs 6%, P=0.015), "perfectionism" (43% vs 14%, P=0.016), and "social insecurity" (50% vs 22, P=0.035) profiles. CONCLUSION: Our study shows a strong association of the compulsive nocturnal behaviors SRED and NS with adult NC.