Sleepwalking in Parkinson's disease: a questionnaire-based survey

Sleepwalking (SW) corresponds to a complex sleep-associated behavior that includes locomotion, mental confusion, and amnesia. SW is present in about 10% of children and 2-3% of adults. In a retrospective series of 165 patients with Parkinson's disease (PD), we found adult-onset ("de novo”) SW "de novo” in six (4%) of them. The aim of this study was to assess prospectively and systematically the frequency and characteristics of SW in PD patients. A questionnaire including items on sleep quality, sleep disorders, and specifically also SW and REM sleep behavior disorder (RBD), PD characteristics and severity, was sent to the members of the national PD patients organization in Switzerland. In the study, 36/417 patients (9%) reported SW, of which 22 (5%) had adult-onset SW. Patients with SW had significantly longer disease duration (p=0.035), they reported more often hallucinations (p=0.004) and nightmares (p=0.003), and they had higher scores, suggestive for RBD in a validated questionnaire (p=0.001). Patients with SW were also sleepier (trend to a higher Epworth Sleepiness Scale score, p=0.055). Our data suggest that SW in PD patients is (1) more common than in the general population, and (2) is associated with RBD, nightmares, and hallucinations. Further studies including polysomnographic recordings are needed to confirm the results of this questionnaire-based analysis, to understand the relationship between SW and other nighttime wandering behaviors in PD, and to clarify the underlying mechanism

EEG after sleep deprivation is a sensitive tool in the first diagnosis of idiopathic generalized but not focal epilepsy

OBJECTIVES: Electroencephalography (EEG) is an essential tool in the diagnosis of epilepsy. EEG after sleep deprivation might increase the likelihood of finding specific epileptiform abnormalities. However conflicting data exist concerning the sensitivity and specificity of this method. We aimed to evaluate the role of EEG after sleep deprivation in the first diagnosis of epilepsy. METHODS: We analyzed retrospectively the medical histories of patients who underwent at least one unspecific standard EEG and a subsequent EEG after sleep deprivation during the time period from 2001 to 2014 at the University Hospital Zurich because of suspected epilepsy. RESULTS: Out of 237 patients who fulfilled all inclusion criteria, 69 were finally diagnosed with epilepsy. Seventeen of them showed interictal epileptiform patterns in EEGs after sleep deprivation, giving this method an overall sensitivity of 25%. Sensitivity of EEG after sleep deprivation was superior in patients with primary generalized epilepsies compared to patients with focal epilepsies (64% vs. 17%, p=0.0011). Overall EEG after sleep deprivation was not more sensitive than a subsequent repeated standard EEG in a subgroup of 55 patients (22% vs. 9%; p=0.065). CONCLUSION: After an unspecific standard EEG, EEG after sleep deprivation is a useful tool to increase diagnostic sensitivity in patients with idiopathic generalized epilepsy but not in those with focal epilepsy. SIGNIFICANCE: This study provides further evidence about the usefulness of EEG after sleep deprivation as an additional diagnostic tool in epilepsy

Remitting narcolepsy? Longitudinal observations in a hypocretin-deficient cohort

Study Objective Narcolepsy type 1 (NT1) is considered a chronic, incurable disease. Excessive daytime sleepiness (EDS) is typically the most troublesome symptom, and more difficult to control by pharmacologic treatment than cataplexy. Although many NT1 patients are monitored by regular follow-ups, the purported relentless persistence of EDS has rarely been the object of longitudinal studies. Methods Retrospective analysis of 26 well-defined hypocretin-deficient NT1 patients who underwent longitudinal assessments of Epworth sleepiness scale (ESS) scores under stable pharmacotherapy. We present detailed case reports of four patients with unusual spontaneous improvement. Results Over a mean observation period of 5 years, changes in ESS scores between first and last examination were ≤4 points in 19 patients (73%). Three patients deteriorated by 5 points, four patients ameliorated by 7-11 points. Among the latter, subjective sleepiness resolved in all four patients, and three of them continued showing ESS scores 8 minutes), one of whom did not fall asleep during maintenance of wakefulness test. Multiple linear regression analysis identified higher cerebrospinal fluid (CSF) hypocretin level (p < 0.001) and absence of fragmented nighttime sleep (p = 0.001) as independent associates of EDS improvement. Conclusions The longitudinal course of NT1-related sleepiness is not invariably stable, but included spontaneous deterioration or improvement in 27%. Spontaneous improvement can persist after treatment discontinuation and resemble remission. Milder hypocretin deficiency and good nighttime sleep may predict a more favorable disease course

Sleep-Related Rhythmic Movement Disorder in Triplets: Evidence for Genetic Predisposition?

Sleep-related rhythmic movement disorder (RMD) is common in very young children but rarely persists beyond childhood. Despite its high frequency, the underlying pathophysiology remains unclear. Familial occurrence is rare. Here we present monozygotic female triplets, all of them being affected by body rolling in terms of RMD. Furthermore, they all present with an additional genetic disease, cystic fibrosis, with the same documented mutation of the cystic fibrosis transmembrane conductance regulator gene (F508del-CFTR). Because all three monozygotic siblings are concordant for RMD, genetic factors may contribute to the time course of the disorder

Extending sleep to confirm insufficient sleep syndrome is challenging

Insufficient sleep syndrome (ISS) is prevalent, but poorly studied. This descriptive study was performed to determine its diagnostic challenges and clinical characteristics in a large (n = 3,461) retrospective sample from a single sleep laboratory. Based on actigraphy, polysomnography and multiple sleep latency tests, we diagnosed "suspected insufficient sleep syndrome" in patients with chronic sleepiness, short time in bed, longer sleep duration during weekends or vacation, and without evidence of other causes of sleepiness. For the diagnosis of "definite insufficient sleep syndrome", we additionally required objectively confirmed resolution of sleepiness with actigraphy-documented extension of time in bed. We diagnosed "suspected insufficient sleep syndrome" in 300 subjects. In 94 subjects, extension of sleep time with consecutive relief of sleepiness was attempted, but only 37 subjects succeeded, often despite being offered several attempts. "Definite insufficient sleep syndrome" was confirmed in 36 patients. In these subjects, mean time in bed after sleep extension was above 8 hr per night and 84 min longer than at baseline. Narcolepsy-like findings were frequently observed before sleep extension, but no sleep onset rapid eye movement sleep on polysomnography. This study indicates that fulfilling the diagnostic criteria of ISS is challenging in clinical practice. It further corroborates the importance of actigraphy and polysomnography for correct diagnosis

Cortical morphometry in narcolepsy with cataplexy

The sleep-wake disorder narcolepsy with cataplexy is associated with the loss of hypocretin-(orexin-) producing neurons in the lateral hypothalamus. Several studies have reported abnormal cerebral activation in patients with narcolepsy with cataplexy. It remains unclear, however, whether these functional changes are related to structural alterations, particularly at the cortical level. To quantify structural brain changes associated with narcolepsy with cataplexy, we used high-resolution T1-weighted magnetic resonance imaging (MRI) in 12 patients compared with 12 healthy participants matched for age and gender. Subcortical and regional cortical volumes were measured using a method unbiased by non-linear registration. Further whole-brain analyses were conducted, measuring cortical characteristics, such as cortical thickness and gyrification, at thousands of points across each hemisphere using validated algorithms. Statistical analyses accounted for an effect of age and gender. We observed decreased cortical volume in the left paracentral lobule and increased cortical volume in the left caudal part of the middle frontal gyrus in narcoleptic patients compared with controls. Cortical thickness in prefrontal areas was inversely correlated with the severity of narcolepsy. Further, we observed several clusters of cortical thinning in patients with childhood or adolescent onset of narcolepsy compared with patients with adult onset of the disease. Our results suggest that specific anatomical changes may differentiate subgroups of narcolepsy patients with different clinical profiles (such as varying symptom severity or different age at onset). Future studies with larger groups of sleepy patients are required to assess whether distinct patterns of anatomical changes may distinguish narcolepsy from non-hypocretin-deficient hypersomnia disorders

Exploring the impact of experimental sleep restriction and sleep deprivation on subjectively perceived sleep parameters

We aimed to investigate the effect of increased sleep pressure and shortened sleep duration on subjective sleep perception in relation to electroencephalographic sleep measures. We analyzed the data from a study in which 14 healthy male volunteers had completed a baseline assessment with 8 hr time in bed, a sleep deprivation (40 hr of wakefulness) and a sleep restriction protocol with 5 hr time in bed during 7 nights. In this work, we assessed perception index, derived through dividing the subjectively perceived total sleep time, wake after sleep onset and sleep latency duration by the objectively measured one at each condition. We found that total sleep time was subjectively underestimated at baseline and shifted towards overestimation during sleep restriction and after deprivation. This change in accuracy of subjective estimates was not associated with any changes in sleep architecture or sleep depth. Wake after sleep onset was significantly underestimated only during sleep restriction. Sleep latency was always overestimated subjectively without any significant change in this misperception across conditions. When comparing accuracy of subjective and actimetry estimates, subjective estimates regarding total sleep time and wake after sleep onset deviated less from electroencephalography derived measures during sleep restriction and after deprivation. We conclude that self-assessments and actimetry data of patients with chronic sleep restriction should be interpreted cautiously. The subjectively decreased perception of wake after sleep onset could lead to overestimated sleep efficiency in such individuals, whereas the underestimation of sleep time and overestimation of wake after sleep onset by actimetry could lead to further underestimated sleep duration