Biomarkers of neurodegeneration in isolated and antidepressant-related rapid eye movement sleep behavior disorder.

BACKGROUND AND PURPOSE: This study compared the features of isolated rapid eye movement (REM) sleep behavior disorder (iRBD) and antidepressant-related REM sleep behaviour disorder (RBD) with the aim of highlighting markers that might distinguish the two entities. METHODS: The observational cohort study included RBD patients with and without antidepressant use (antiD+ and antiD- patients, respectively), without cognitive impairment and parkinsonism. Clinical features of RBD, subtle motor and non-motor symptoms of parkinsonism, sleep architecture, REM atonia index, dopamine transporter-single photon emission computed tomography (DAT-SPECT) and skin biopsies for the intraneuronal alpha-synuclein (α-syn), were evaluated in the baseline work-up. RESULTS: Thirty-nine patients, 10 antiD+ and 29 antiD-, were included. AntiD+ patients (more frequently female) reported more psychiatric symptoms, less violent dream enactment, and less frequent hyposmia. Dermal α-syn was detected in 93.1% of antiD- versus 30% of antiD+ patients (p = 0.00024). No differences appeared in other motor and non-motor symptoms, Movement Disorder Society-Unified Parkinson's Disease Rating Scale part III score, DAT-SPECT, or polysomnographic features. CONCLUSIONS: Patients with antidepressant-related RBD have clinical and neuropathological features suggesting a lower risk of evolution than those with iRBD.

Exploring the emotional and behavioural profile in paediatric narcolepsy type 1: A case-control study.

Narcolepsy type 1 (NT1) is a central disorder of hypersomnolence often arising in childhood and adolescence. NT1 has a significant, but poorly defined, psychological impact. We aimed to investigate the psycho-social functioning of children and adolescents with NT1. We performed a cross-sectional, child and parent-reported questionnaire survey in 37 children and adolescents (6-17 years) with NT1, compared with age- and sex-matched controls. Questionnaires (SSHS, ESS-CHAD, CDI, MASC, CBCL, CRS-R, and SNAP-IV) evaluated various aspects of behavioural and emotional profiles, sleep habits, and daytime sleepiness. Subsequently, NT1 intra-group analysis was performed to investigate the effect of sex (males vs females) and pharmacological treatment (treated vs non-treated) on psychological features. The NT1 questionnaires total scores were then correlated with the clinical characteristics (age, body mass index [BMI], ESS-CHAD score, cerebrospinal hypocretin-1 [Hcrt-1] levels, and diagnostic delay). Patients with NT1 showed a higher tendency to depressive symptoms, anxiety, somatisation, inattention, hyperactivity, oppositional/defiant problems, and other maladaptive behaviours compared with controls. Among NT1 patients, females showed a higher propensity to anxiety, and non-treated patients displayed higher depressive symptoms. Psychological symptoms increased with age, BMI, and daytime sleepiness in patients with NT1, while a younger age was associated with more frequent somatisation symptoms. Lower cerebrospinal Hcrt-1 levels correlated with poorer social competencies, daily activities, and inattention. Diagnostic delay was associated with a higher impact of depressive symptoms and behavioural problems. NT1 in children and adolescents is associated with poorer functioning in multiple psychological domains calling for a multidisciplinary approach and monitoring to reduce disease burden and to prevent psychiatric consequences.

(Not so) Smart sleep tracking through the phone: Findings from a polysomnography study testing the reliability of four sleep applications.

An increasing number of sleep applications are currently available and are being widely used for in-home sleep tracking. The present study assessed four smartphone applications (Sleep Cycle-Accelerometer, SCa; Sleep Cycle-Microphone, SCm; Sense, Se; Smart Alarm, SA) designed for sleep-wake detection through sound and movement sensors, by comparing their performance with polysomnography. Twenty-one healthy participants (six males, 15 females) used the four sleep applications running on iPhone (provided by the experimenter) simultaneously with portable polysomnography recording at home, while sleeping alone for two consecutive nights. Whereas all apps showed a significant correlation with polysomnography-time in bed, only SA offered significant correlations for sleep efficacy. Furthermore, SA seemed to be quite effective in reliable detection of total sleep time and also light sleep; however, it underestimated wake and partially overestimated deep sleep. None of the apps resulted capable of detecting and scoring rapid eye movement sleep. To sum up, SC (functioning through both accelerometer and microphone) and Se did not result sufficiently reliable in sleep-wake detection compared with polysomnography. SA, the only application offering the possibility of an epoch-by-epoch analysis, showed higher accuracy than the other apps in comparison with polysomnography, but it still shows some limitations, particularly regarding wake and deep sleep detection. Developing scoring algorithms specific for smartphone sleep detection and adding external sensors to record other physiological parameters may overcome the present limits of sleep tracking through smart phone apps.

Protocols of a diagnostic study and a randomized controlled non-inferiority trial comparing televisits vs standard in-person outpatient visits for narcolepsy diagnosis and care: TElemedicine for NARcolepsy (TENAR).

BACKGROUND: Narcolepsy is a rare chronic sleep disorder that typically begins in youth. Excessive daytime sleepiness is the main disabling symptom, but the disease is often associated with severe endocrine-metabolic and psychosocial issues, worsened by a long diagnostic delay, requiring a multidisciplinary approach. The scarcity of reference Sleep Centres forces the patient and family to travel for seeking medical consultations, increasing the economic and psychosocial burden of the disease. Growing evidence suggests that Telemedicine may facilitate patient access to sleep consultations and its non-inferiority in terms of patient satisfaction, adherence to treatment, and symptom improvement for sleep disorders. However, Telemedicine clinical and economic benefits for patients with narcolepsy are still unknown. METHODS: TENAR is a two-part project, including: 1. a cross-sectional study (involving 250 children and adults with suspected narcolepsy) evaluating the accuracy of Teletriage (i.e., a synchronous live interactive sleep assessment through a Televisit) for narcolepsy diagnosis compared to the reference standard; and 2. a two-arm, parallel, open randomized controlled trial (RCT) to demonstrate the non-inferiority of the multidisciplinary care of narcolepsy through Televisits versus standard care. In this RCT, 202 adolescents (> 14 y.o.) and adults with narcolepsy will be randomly allocated (1:1 ratio) either to Televisits via videoconference or to standard in-person outpatient follow-up visits (control arm). The primary outcome is sleepiness control (according to the Epworth Sleepiness Scale). Secondary outcomes are other symptoms control, compliance with treatment, metabolic control, quality of life, feasibility, patient and family satisfaction with care, safety, and disease-related costs. At baseline and at 12 months, patients will undergo neurologic, metabolic, and psychosocial assessments and we will measure primary and secondary outcomes. Primary outcomes will be also measured at 6 months (remotely or in person, according to the arm). DISCUSSION: TENAR project will assess, for the first time, the feasibility, accuracy, efficacy and safety of Telemedicine procedures applied to the diagnosis and the multidisciplinary care of children and adults with narcolepsy. The study may be a model for the remote management of other rare disorders, offering care access for patients living in areas lacking medical centres with specific expertise. TRIAL REGISTRATION: Number of the Tele-multidisciplinary care study NCT04316286. Registered 20 March 2020.

Excessive daytime sleepiness in narcolepsy and central nervous system hypersomnias.

PURPOSE: Excessive daytime sleepiness (EDS) is the core complaint of central nervous system (CNS) hypersomnias. In this mini-review, we summarized EDS features in CNS hypersomnias to provide a guide for differential diagnosis purposes. METHODS: A review of recent literature was performed to provide an update in CNS hypersomnias. RESULTS: At clinical evaluation, narcolepsy patients report a good restorative potential of sleep together with the frequent occurrence of dreaming even during short-lasting naps. These features are mirrored by the neurophysiological evidence of REM sleep at sleep onset (SOREMP) during the Multiple Sleep Latency Test (MSLT), a specific marker. Conversely, patients with idiopathic hypersomnia (IH) complain sleep inertia and prolonged nocturnal sleep. Polysomnographic studies show high sleep propensity on the MSLT or high 24-h total sleep time during continuous monitoring. Patients with insufficient sleep syndrome (ISS) can present with variable clinical EDS features in between narcolepsy and IH. ISS diagnosis is based on the clinical evidence of nocturnal sleep curtailment (weekdays versus vacations) associated with the disappearance of EDS complaint after sleep extension. Polysomnographic data are not required, but when the MSLT is performed, ISS patients can present with SOREMP arising from non-REM stage 2 sleep (vs narcolepsy patients entering into SOREM most frequently from wakefulness). Kleine-Levin Syndrome is characterized by recurrent episodes of enormously prolonged sleep time lasting days associated with abnormal cognition and behavior intermixed by asymptomatic periods, a sleep pattern that can be well documented by actigraphy. CONCLUSIONS: Different CNS hypersomnias present with specific features of EDS are useful to guide the clinician to apply and interpret appropriate neurophysiological investigations.

The spectrum of REM sleep-related episodes in children with type 1 narcolepsy.

Type 1 narcolepsy is a central hypersomnia due to the loss of hypocretin-producing neurons and characterized by cataplexy, excessive daytime sleepiness, sleep paralysis, hypnagogic hallucinations and disturbed nocturnal sleep. In children, close to the disease onset, type 1 narcolepsy has peculiar clinical features with severe cataplexy and a complex admixture of movement disorders occurring while awake. Motor dyscontrol during sleep has never been systematically investigated. Suspecting that abnormal motor control might affect also sleep, we systematically analysed motor events recorded by means of video polysomnography in 40 children with type 1 narcolepsy (20 females; mean age 11.8 ± 2.6 years) and compared these data with those recorded in 22 age- and sex-matched healthy controls. Motor events were classified as elementary movements, if brief and non-purposeful and complex behaviours, if simulating purposeful behaviours. Complex behaviours occurring during REM sleep were further classified as 'classically-defined' and 'pantomime-like' REM sleep behaviour disorder episodes, based on their duration and on their pattern (i.e. brief and vivid-energetic in the first case, longer and with subcontinuous gesturing mimicking daily life activity in the second case). Elementary movements emerging either from non-REM or REM sleep were present in both groups, even if those emerging from REM sleep were more numerous in the group of patients. Conversely, complex behaviours could be detected only in children with type 1 narcolepsy and were observed in 13 patients, with six having 'classically-defined' REM sleep behaviour disorder episodes and seven having 'pantomime-like' REM sleep behaviour disorder episodes. Complex behaviours during REM sleep tended to recur in a stereotyped fashion for several times during the night, up to be almost continuous. Patients displaying a more severe motor dyscontrol during REM sleep had also more severe motor disorder during daytime (i.e. status cataplecticus) and more complaints of disrupted nocturnal sleep and of excessive daytime sleepiness. The neurophysiological hallmark of this severe motor dyscontrol during REM sleep was a decreased atonia index. The present study reports for the first time the occurrence of a severe and peculiar motor disorder during REM sleep in paediatric type 1 narcolepsy and confirms the presence of a severe motor dyscontrol in these patients, emerging not only from wakefulness (i.e. status cataplecticus), but also from sleep (i.e. complex behaviours during REM sleep). This is probably related to the acute imbalance of the hypocretinergic system, which physiologically acts by promoting movements during wakefulness and suppressing them during sleep.

The Brain Correlates of Laugh and Cataplexy in Childhood Narcolepsy.

The brain suprapontine mechanisms associated with human cataplexy have not been clarified. Animal data suggest that the amygdala and the ventromedial prefrontal cortex are key regions in promoting emotion-induced cataplectic attacks. Twenty-one drug-naive children/adolescent (13 males, mean age 11 years) with recent onset of narcolepsy type 1 (NT1) were studied with fMRI while viewing funny videos using a "naturalistic" paradigm. fMRI data were acquired synchronously with EEG, mylohyoid muscle activity, and the video of the patient's face. Whole-brain hemodynamic correlates of (1) a sign of fun and amusement (laughter) and of (2) cataplexy were analyzed and compared. Correlations analyses between these contrasts and disease-related variables and behavioral findings were performed. SIGNIFICANCE STATEMENT: In this study we reported for the first time in humans the brain structures whose neural activity is specifically and consistently associated with emotion-induced cataplexy. To reach this goal drug-naive children and adolescents with recent onset narcolepsy type 1 were investigated. In narcolepsy caused by hypocretin/orexin deficiency, cataplexy is associated with a marked increase in neural activity in the amygdala, the nucleus accumbens, and the ventromedial prefrontal cortex, which represent suprapontine centers that physiologically process emotions and reward. These findings confirm recent data obtained in the hypocretin knock-out mice and suggest that the absence of hypothalamic hypocretin control on mesolimbic reward centers is crucial in determining cataplexy induced by emotions. Emotion-induced laughter occurred in 16 patients, and of these 10 showed cataplexy for a total of 77 events (mean duration = 4.4 s). Cataplexy was marked by brief losses of mylohyoid muscle tone and by the observation of episodes of facial hypotonia, jaw drop, and ptosis. During laughter (without cataplexy) an increased hemodynamic response occurred in a bilateral network involving the motor/premotor cortex and anterior cingulate gyrus. During cataplexy, suprapontine BOLD signal increase was present in the amygdala, frontal operculum-anterior insular cortex, ventromedial prefrontal cortex, and the nucleus accumbens; BOLD signal increases were also observed at locus ceruleus and in anteromedial pons. The comparison of cataplexy versus laugh episodes revealed the involvement of a corticolimbic network that processes reward and emotion encompassing the anterior insular cortex, the nucleus accumbens, and the amygdala.

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.

Electroencephalogram paroxysmal θ characterizes cataplexy in mice and children.

Astute control of brain activity states is critical for adaptive behaviours and survival. In mammals and birds, electroencephalographic recordings reveal alternating states of wakefulness, slow wave sleep and paradoxical sleep (or rapid eye movement sleep). This control is profoundly impaired in narcolepsy with cataplexy, a disease resulting from the loss of orexin/hypocretin neurotransmitter signalling in the brain. Narcolepsy with cataplexy is characterized by irresistible bouts of sleep during the day, sleep fragmentation during the night and episodes of cataplexy, a sudden loss of muscle tone while awake and experiencing emotions. The neural mechanisms underlying cataplexy are unknown, but commonly thought to involve those of rapid eye movement-sleep atonia, and cataplexy typically is considered as a rapid eye movement sleep disorder. Here we reassess cataplexy in hypocretin (Hcrt, also known as orexin) gene knockout mice. Using a novel video/electroencephalogram double-blind scoring method, we show that cataplexy is not a state per se, as believed previously, but a dynamic, multi-phased process involving a reproducible progression of states. A knockout-specific state and a stereotypical paroxysmal event were introduced to account for signals and electroencephalogram spectral characteristics not seen in wild-type littermates. Cataplexy almost invariably started with a brief phase of wake-like electroencephalogram, followed by a phase featuring high-amplitude irregular theta oscillations, defining an activity profile distinct from paradoxical sleep, referred to as cataplexy-associated state and in the course of which 1.5-2 s high-amplitude, highly regular, hypersynchronous paroxysmal theta bursts (∼7 Hz) occurred. In contrast to cataplexy onset, exit from cataplexy did not show a predictable sequence of activities. Altogether, these data contradict the hypothesis that cataplexy is a state similar to paradoxical sleep, even if long cataplexies may evolve into paradoxical sleep. Although not exclusive to overt cataplexy, cataplexy-associated state and hypersynchronous paroxysmal theta activities are highly enriched during cataplexy in hypocretin/orexin knockout mice. Their occurrence in an independent narcolepsy mouse model, the orexin/ataxin 3 transgenic mouse, undergoing loss of orexin neurons, was confirmed. Importantly, we document for the first time similar paroxysmal theta hypersynchronies (∼4 Hz) during cataplexy in narcoleptic children. Lastly, we show by deep recordings in mice that the cataplexy-associated state and hypersynchronous paroxysmal theta activities are independent of hippocampal theta and involve the frontal cortex. Cataplexy hypersynchronous paroxysmal theta bursts may represent medial prefrontal activity, associated in humans and rodents with reward-driven motor impulse, planning and conflict monitoring.

Clinical and polysomnographic course of childhood narcolepsy with cataplexy.

Our aim was to investigate the natural evolution of cataplexy and polysomnographic features in untreated children with narcolepsy with cataplexy. To this end, clinical, polysomnographic, and cataplexy-video assessments were performed at diagnosis (mean age of 10 ± 3 and disease duration of 1 ± 1 years) and after a median follow-up of 3 years from symptom onset (mean age of 12 ± 4 years) in 21 children with narcolepsy with cataplexy and hypocretin 1 deficiency (tested in 19 subjects). Video assessment was also performed in two control groups matched for age and sex at first evaluation and follow-up and was blindly scored for presence of hypotonic (negative) and active movements. Patients' data at diagnosis and at follow-up were contrasted, compared with controls, and related with age and disease duration. At diagnosis children with narcolepsy with cataplexy showed an increase of sleep time during the 24 h; at follow-up sleep time and nocturnal sleep latency shortened, in the absence of other polysomnographic or clinical (including body mass index) changes. Hypotonic phenomena and selected facial movements decreased over time and, tested against disease duration and age, appeared as age-dependent. At onset, childhood narcolepsy with cataplexy is characterized by an abrupt increase of total sleep over the 24 h, generalized hypotonia and motor overactivity. With time, the picture of cataplexy evolves into classic presentation (i.e., brief muscle weakness episodes triggered by emotions), whereas total sleep time across the 24 h decreases, returning to more age-appropriate levels.

Role of Daytime Continuous Polysomnography in the Diagnosis of Pediatric Narcolepsy Type 1.

BACKGROUND AND OBJECTIVES: Narcolepsy type 1 (NT1) is still largely underdiagnosed or diagnosed too late in children. Difficulties in obtaining rapid and reliable diagnostic evaluations of the condition in clinical practice partially explain this problem. Predictors of NT1 include cataplexy and sleep-onset REM periods (SOREMPs), documented during nocturnal polysomnography (N-PSG) or through the multiple sleep latency test (MSLT), although low CSF hypocretin-1 (CSF hcrt-1) is the definitive biological disease marker. Obtaining reliable MSLT results is not always feasible in children; therefore, this study aimed to validate daytime continuous polysomnography (D-PSG) as an alternative diagnostic tool. METHODS: Two hundred consecutive patients aged younger than 18 years (112 with NT1; 25 with other hypersomnias, including narcolepsy type 2 and idiopathic hypersomnia; and 63 with subjective excessive daytime sleepiness) were randomly split into 2 groups: group 1 (n = 133) for the identification of diagnostic markers and group 2 (n = 67) for the validation of the detected markers. The D-PSG data collected included the number of spontaneous naps, total sleep time, and the number of daytime SOREMPs (d-SOREMP). D-PSG data were tested against CSF hcrt-1 deficiency (NT1 diagnosis) as the gold standard using receiver operating characteristic (ROC) curve analysis in group 1. ROC diagnostic performances of single and combined D-PSG parameters were tested in group 1 and validated in group 2. RESULTS: In group 1, the areas under the ROC curve (AUCs) were 0.91 (95% CI 0.86-0.96) for d-SOREMPs, 0.81 (95% CI 0.74-0.89) for the number of spontaneous naps, and 0.70 (95% CI 0.60-0.79) for total sleep time. A d-SOREMP count ≥1 (sensitivity of 95% and specificity of 72%), coupled with a diurnal total sleep time above 60 minutes (sensitivity of 89% and specificity of 91%), identified NT1 in group 1 with high reliability (area under the ROC curve of 0.93, 95% CI 0.88-0.97). These results were confirmed in the validation group with an AUC of 0.88 (95% CI 0.79-0.97). DISCUSSION: D-PSG recording is an easily performed, cost-effective, and reliable tool for identifying NT1 in children. Further studies should confirm its validity with home D-PSG monitoring. These alternative procedures could be used to confirm NT1 diagnosis and curtail diagnostic delay.

Polysomnographic study of nocturnal sleep in idiopathic hypersomnia without long sleep time.

We investigated nocturnal sleep abnormalities in 19 patients with idiopathic hypersomnia without long sleep time (IH) in comparison with two age- and sex- matched control groups of 13 normal subjects (C) and of 17 patients with narcolepsy with cataplexy (NC), the latter considered as the extreme of excessive daytime sleepiness (EDS). Sleep macro- and micro- (i.e. cyclic alternating pattern, CAP) structure as well as quantitative analysis of EEG, of periodic leg movements during sleep (PLMS), and of muscle tone during REM sleep were compared across groups. IH and NC patients slept more than C subjects, but IH showed the highest levels of sleep fragmentation (e.g. awakenings), associated with a CAP rate higher than NC during lighter sleep stages and lower than C during slow wave sleep respectively, and with the highest relative amount of A3 and the lowest of A1 subtypes. IH showed a delta power in between C and NC groups, whereas muscle tone and PLMS had normal characteristics. A peculiar profile of microstructural sleep abnormalities may contribute to sleep fragmentation and, possibly, EDS in IH.

Cardiovascular variability as a function of sleep-wake behaviour in narcolepsy with cataplexy.

Hypocretin/orexin signalling varies among sleep-wake behaviours, impacts upon cardiovascular autonomic control and is impaired in patients with narcolepsy with cataplexy (NC). However, evidence concerning disturbed cardiovascular autonomic control in NC patients is contrasting, and limited mainly to waking behaviour. We thus investigated whether control of cardiovascular variability is altered in NC patients during wakefulness preceding sleep, light (1-2) and deep (3-4) stages of non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. Polysomnographic recordings and finger blood pressure measurements were performed on nine drug-free male NC patients and nine matched healthy control subjects during spontaneous sleep-wake behaviour in a standardized laboratory environment. Indices of autonomic function were computed based on spontaneous fluctuations of systolic blood pressure (SBP) and heart period (HP). During wakefulness before sleep, NC patients showed significant decreases in indices of vagal HP modulation, cardiac baroreflex sensitivity and amplitude of central autonomic (feed-forward) cardiac control compared with control subjects. During NREM sleep, the negative correlation between HP and subsequent SBP values was greater in NC patients than in control subjects, suggesting a greater contribution of central autonomic commands to cardiac control. Collectively, these results provide preliminary evidence that autonomic control of cardiac variability by baroreflex and central autonomic (feed-forward) mechanisms is altered in NC patients during spontaneous sleep-wake behaviour, and particularly during wakefulness before sleep.

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.

Phenomenology and psychiatric correlates of pseudocataplexy.

STUDY OBJECTIVES: Pseudocataplexy is a rare functional neurological disorder that mimics cataplexy, pathognomonic for narcolepsy type 1 (NT1). We describe the psychiatric comorbidity and personality traits of patients with pseudocataplexy versus NT1 cases. METHODS: The case-control observational study enrolled consecutive patients with pseudocataplexy and a control group of age-matched consecutive NT1 patients. The diagnostic work-up included a structured interview, 48-hour polysomnography, multiple sleep latency test, cataplexy provoking test, and hypocretin-1 measurement in cerebrospinal fluid.All participants were administered Beck Depression Inventory, State-Trait Anxiety Inventory, Patient Health Questionnaire-15 (PHQ-15), Personality Inventory for DSM-5 brief form, and quality of life (QoL) measurement by 36-item Short Form health survey (SF-36). RESULTS: Fifteen patients with pseudocataplexy and 30 with NT1 were included. Despite the suspicion of possible cataplexy, none of the pseudocataplexy participants fulfilled international diagnostic criteria for NT1. Pseudocataplexy patients presented higher rates of moderate state anxiety (40% vs. 10%, p=0.018), medium level of somatic symptoms, defined by PHQ-15 score >10 (66.7% vs. 16.7%, p=0.003), and a trend towards moderate-to-severe depressive symptoms (33.3% vs. 10%, p=0.054) compared to NT1. No significant differences in personality traits emerged. Pseudocataplexy patients had worse QoL profile in almost all SF-36 domains including physical (mean±SD: 37.7±9.88 vs. 51.13±7.81, p<0.001) and mental (mean±SD: 33.36±12.69 vs.42.76±11.34, p=0.02) summary scores. CONCLUSIONS: Patients with pseudocataplexy present more severe psychiatric symptoms and a lower QoL profile in comparison with patients with NT1. The severe somatoform and affection impairment in pseudocataplexy may explain the poorer QoL and should require a tailored therapeutic approach.

Sleep Bruxism and Orofacial Pain in Patients with Sleep Disorders: A Controlled Cohort Study.

BACKGROUND: The gold standard for the diagnosis of sleep bruxism (SB) is laboratory polysomnography (L-PSG) recording. However, many clinicians still define SB using patients' self-assessment and/or clinical tooth wear (TW). The purpose of this cross-sectional controlled study was to compare the prevalence of TW, head-neck muscles sensitivity and Temporomandibular Disorders (TMD) between SB and non-SB patients diagnosed with L-PSG in a cohort of patient with sleep disorders (SD). METHODS: 102 adult subjects with suspected SD underwent L-PSG recording to assess the presence of sleep disorder and SB. TW was clinically analyzed using TWES 2.0. The pressure pain threshold (PPT) of masticatory muscles were assessed using a Fisher algometer. Diagnostic criteria for TMD (DC/TMD) were used to evaluate the presence of TMD. SB self-assessment questionnaires were administered. TWES score, PPT, TMD prevalence and questionnaire results were compared between SB and non-SB patients. RESULTS: 22 SB patients and 66 non-SB patients with SD were included. No significant differences emerged between groups in regards to TW, the PPT values, or SB's self-assessment questionnaires as well the prevalence of TMD. CONCLUSION: in a SD population, TW is not pathognomonic of active SB and SB self-assessment is not reliable. There seems to be no correlation between SB, TMD and head/neck muscle sensitivity.

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

BACKGROUND: First symptoms of narcolepsy mostly present during childhood. Pharmacological management options in children are limited, also due to approval status. Pitolisant is an inverse histamine 3 receptor agonist and has been approved for the treatment of adult narcolepsy with or without cataplexy by EMA and FDA. Clinical experience indicates for a beneficial use also in children and adolescents. Our goal was to evaluate the effects and tolerability of pitolisant in narcolepsy children/adolescents in a real-world setting. METHODS: This multicentre retrospective observational study included 55 patients with narcolepsy from three international narcolepsy centers (Germany, France and Italy) who were treated with pitolisant. Patients were eligible if they were at least 6 years old and diagnosed with narcolepsy type 1 or 2. Demographic and clinical characteristics, questionnaires, sleep medicine and laboratory data were collected. RESULTS: 55 children/adolescents (25 girls, 45.45%, 30 boys, 54.55%) aged 6-18 years, with narcolepsy (type 1 = 92.7%, type 2 = 7.3%), were treated with pitolisant. The mean pitolisant dose was 34.1 mg/d. Treatment was effective for excessive daytime sleepiness (EDS) and cataplexy: the pediatric Epworth Sleepiness Scale (ESS) score decreased from 19 to 13.5 (p < 0.001) and the weekly cataplexy frequency improved from 7.9 at baseline to 5.2 (p < 0.001). Treatment with pitolisant was well tolerated. Side effects were mild and mostly short-term. Insomnia was reported most frequently (5.5%). CONCLUSION: First real-world results suggest that pitolisant treatment is effective in improving EDS and cataplexy in children with narcolepsy, and also is well tolerated.

Periodic leg movements during sleep in narcoleptic patients with or without restless legs syndrome.

We compared periodic and non-periodic leg movements during sleep and polysomnography in patients with narcolepsy with cataplexy (NC) with or without restless legs syndrome (RLS) with matched idiopathic RLS (iRLS) and control subjects. We enrolled 100 patients with NC: 17 having RLS were compared with 34 sex- and age-matched patients without RLS and with 17 normal controls and 17 iRLS subjects. Periodic leg movements were highest in iRLS and lowest in controls, with those in NC with RLS very close to iRLS, but higher than those in NC without RLS. The periodicity indexes showed the highest value in iRLS followed by NC with or without RLS and, finally, by controls. The inter-leg movement intervals peaked between 10 and 50 s in NC with RLS and in iRLS, the former did not display the nocturnal gradual decrease of periodic leg movements typical of iRLS. Periodic leg movements during sleep and polysomnography displayed specific features in RLS and NC, respectively, with NC with RLS showing an intermediate pattern. Even if RLS is only detected by targeted interview in NC, its frequency and impact on night-time sleep architecture and continuity suggest that this condition should be routinely searched for in NC.

Catathrenia under sodium oxybate in narcolepsy with cataplexy.

PURPOSE: This study aims to report on catathrenia occurring in narcolepsy with cataplexy (NC) patients under sodium oxybate (SO) treatment. Catathrenia is a parasomnia characterized by groaning and an abnormal respiratory pattern during sleep. METHODS: Fifty-one patients with NC and starting SO therapy underwent a baseline overnight polysomnography (PSG) to detect any sleep-related breathing disorders (SRBD). To avoid risks due to a possible central respiratory control depression by SO, all patients with concomitant obstructive sleep apnea (OSA) were treated with a nasal continuous positive airway pressure (nCPAP) device. After 2 months of treatment with SO, all patients underwent a follow-up overnight PSG to investigate possible newly occurring SRBD. They also underwent a semi-structured clinical interview to monitor other potential SO side effects. RESULTS: At baseline, four out of 51 patients showed simple snoring, and eight, mild to severe OSA. After a titration PSG night, patients with OSA received a nCPAP device. After 2 months of SO treatment, 28 patients (54.9%) showed SO-related side effects, including SRBD in 11 (21.6%). The follow-up PSG showed a respiratory pattern characteristic of catathrenia in seven patients (13.7%) as a newly observed and possibly benign SO side effect, and ruled out a worsening of OSA. CONCLUSIONS: Catathrenia should be considered a possible side effect in NC patients under SO treatment and should be accurately identified to prevent unnecessary SO withdrawal.

REM sleep behavior disorder with predominant nightmares in a patient with ischemic pontine lesions.

Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia typically associated with synucleinopathy and evolving to neurodegenerative disorders. RBD is caused by impairment of brainstem nuclei controlling REM sleep muscle atonia. Rarely, focal lesions of the brainstem can cause secondary RBD. We present the case of a 74-year-old patient, previously evaluated at age 70 years for insomnia and periodic limb movements during sleep, who then rapidly developed unpleasant dreams with minor motor behavior, affecting his sleep quality. Polysomnography recorded REM sleep without atonia and motor behaviors in REM sleep. Ischemic lesions in the pons were detected by magnetic resonance imaging. Clinical, biological, and instrumental biomarkers of neurodegeneration were repeatedly negative at 2 years' follow-up. Although rare, a lesional cause of RBD must be considered in cases of atypical presentation and without evidence of neurodegeneration. The complaint of unpleasant dreams suggests a possible role of brainstem nuclei controlling REM sleep atonia in affecting oneiric content. CITATION: Biscarini F, Montini A, Antelmi E, Vandi S, Pizza F, Plazzi G. REM sleep behavior disorder with predominant nightmares in a patient with ischemic pontine lesions. J Clin Sleep Med. 2022;18(3):945-948.