Video-polysomnographic Recording Research Articles

Restless Sleep Disorder and the Role of Iron in Other Sleep-Related Movement Disorders and ADHD

In the last few years, restless sleep has been described as the key element of many clinical issues in childhood, leading to the recognition of “restless sleep disorder” (RSD) as a new proposed diagnostic category. The essential aid of video-polysomnographic recordings enables detection and quantification of the “large muscle group movements” (such as limb movements and repositioning) frequently described by parents of children with RSD. Strong evidence links iron deficiency to the pathophysiology of sleep-related movement disorders such as RSD, restless legs syndrome, periodic limb movement disorder, and attention deficit hyperactivity disorder (ADHD) due to the important role played by the brain dopamine production system. Serum ferritin is the main parameter used to evaluate iron deficiency in patients with sleep-related movement disorders. Iron supplementation is recommended when the serum ferritin level is <50 ng/mL, since the literature emphasizes the correlation between lower levels of serum ferritin, serum iron, and cerebrospinal fluid ferritin, and increased symptom severity. Moreover, several studies report an improvement in symptoms when ferritin levels are kept above 50 ng/mL. In this narrative review, we discuss the role of iron in sleep-related movement disorders, as well as ADHD, highlighting not only the connection between these two conditions, but also the relevance of iron supplementation for symptom improvement.

Severity of REM sleep without atonia correlates with measures of cognitive impairment and depressive symptoms in REM sleep behaviour disorder.

This study aimed to correlate REM sleep without atonia (RSWA) and neuropsychological data in patients with idiopathic/isolated REM sleep behaviour disorder (iRBD) and those with RBD associated with Parkinson's disease (PDRBD), in order to assess whether higher degrees of RSWA are related to poorer cognitive performance. A total of 142 subjects were enrolled: 48 with iRBD, 55 with PDRBD, and 39 PD without RBD (PDnoRBD). All participants underwent video-polysomnographic recording, clinical and neuropsychological assessment. RSWA was quantified according to two manual scoring methods (Montréal, SINBAR) and one automated (REM atonia index, RAI). Mild cognitive impairment (MCI) was diagnosed according to diagnostic criteria for MCI in Parkinson's disease. The relationship between neuropsychological scores and RSWA metrics was explored by multiple linear regression analysis and logistic regression models. Patients with iRBD showed significantly lower visuospatial functions and working memory, compared with the others. More severe RSWA was associated with a higher risk of reduced visuospatial abilities (OR 0.15), working memory (OR 2.48), attention (OR 2.53), and semantic fluency (OR 0.15) in the iRBD. In the whole group, a greater RSWA was associated with an increased risk for depressive symptoms (OR 3.6). A total of 57(40%) MCI subjects were found (17 iRBD, 26 PDRBD, and 14 PDnoRBD). Preserved REM-atonia was associated with a reduced odds of multi-domain MCI in the whole study population (OR 0.54). In conclusion, a greater severity of RSWA was associated with an increased risk for poor cognitive performance and depressive mood in patients with RBD. Moreover, higher RAI was associated with a lower risk of multi-domain MCI.

Is camera recording crucial for the correct diagnosis of sleep bruxism in polysomnography?

Due to potential issues, several sleep laboratories conduct sleepbruxism diagnosis without the use of a camera, instead relying mostly on electromyographic monitoring. The purpose of the study was to determine if a camera is necessary for the polysomnographic evaluation of sleep bruxism and how sleep bruxism parameters change when a camera is not utilised. The study material was actual polysomnographic recordings made in the years 2017-2020. A total of 199 single-night video-polysomnographic recordings of patients who were suspected of having sleep bruxism were chosen at random. The first analysis involved the evaluation of the video recording, while in the second video recording was not used. The findings revealed that all the examined sleepbruxism indices had statistically significantly higher values for the recordings made without the use of a camera. According to the findings, noncamera recordings had decreased sensitivity and specificity when the criteria ofbruxism and mild-to-moderate bruxism were taken into account, and decreased sensitivity in the case of the criterion of severe bruxism. Sleep efficiency, the apnea/hypopnea index, and arousals had independent effects on the bruxism episode index value in the analysis of noncamera recordings. In conclusion, camera-based polysomnography still appears to be the most reliable way to assess the severity of sleep bruxism, particularly in patients who also report other sleep disturbances. The presence of symptoms of sleep-disordered breathing, insomnia, or other sleep disorders should prompt us to use camera-based diagnostics.

EEG Activation Does Not Differ in Simple and Complex Episodes of Disorders of Arousal: A Spectral Analysis Study.

PurposeDisorders of arousal (DoA) are characterized by incomplete awakening from NREM sleep, with the admixture of both deep sleep and wake EEG activity. Previous observations suggested that changes in EEG activity could be detected in the seconds preceding DoA episodes. The aims of this work were to characterize the topography of EEG spectral changes prior to DoA episodes and to investigate whether or not behavioral complexity could be predicted by changes in EEG immediately preceding behavioral onsets.Patients and MethodsWe collected 103 consecutive video-polysomnographic recordings of 53 DoA adult patients and classified all episodes as simple, rising and complex arousal movements. For each episode, a 5-second window preceding its motor onset (“pre-event”) and a 60-second window from 2 to 3 minutes before the episodes (“baseline”) were compared. Subsequently, a between-group comparison was performed for the pre-event of simpler versus the more complex episodes.ResultsSpectral analysis over 325 DoA episodes showed an absolute significant increase prior to DoA episodes in all frequency bands excluding sigma, which displayed the opposite effect. In normalized maps, the increase was relatively higher over the central/anterior areas for both slow and fast frequency bands. No significant differences emerged from the comparison between simpler and more complex episodes.ConclusionTaken together, these results show that deep sleep and wake-like EEG rhythms coexist over overlapping areas before DoA episodes, suggesting an alteration of local sleep mechanisms. Episodes of different complexity are preceded by a similar EEG activation, implying that they possibly share a similar pathophysiology.

Scoring of large muscle group movements during sleep: an International Restless Legs Syndrome Study Group position statement.

There is a gap in the manuals for scoring sleep-related movements because of the absence of rules for scoring large movements. A taskforce of the International Restless Legs Syndrome Study Group (IRLSSG) elaborated rules that define the detection and quantification of movements involving large muscle groups. Consensus on each of the criteria in this article was reached by testing the presence of consensus on a first proposal; if no consensus was achieved, the concerns were considered and used to modify the proposal. This process was iterated until consensus was reached. A preliminary analysis of the duration of movements involving large muscle groups was also carried out on data from two previous studies, which, however, used a visual analysis of video-polysomnographic (PSG) recordings obtained from children or adults. Technical specifications and scoring rules were designed for the detection and quantification of large muscle group movements during sleep with a duration between 3 and 45 seconds in adults or 3 and 30 seconds in children, characterized by an increase in electromyographic activity and/or the occurrence of movement artifact in any combination of at least two recommended channels and not meeting the criteria for any other type of movement. Large muscle group movements are often accompanied by sleep stage changes, arousals, awakenings, and heart rate rises. The absence of clear and detailed rules defining them has likely impeded the development of studies that might disclose their clinical relevance; these new rules fill this gap.

The Arousal Disorders Questionnaire: a new and effective screening tool for confusional arousals, Sleepwalking and Sleep Terrors in epilepsy and sleep disorders units

BackgroundArousal Disorders (DoA) include Confusional Arousals, Sleepwalking and Sleep Terrors. DoA diagnosis is mainly clinical but no validated questionnaires exist for DoA screening according to the criteria of the International Classification of Sleep Disorders, Third Edition. Recently our group proposed the Arousal Disorders Questionnaire (ADQ) as a new diagnostic tool for DoA diagnosis. The objective of this study was to evaluate the diagnostic accuracy of the ADQ in a sleep and epilepsy center. MethodsOne interviewer blinded to clinical and video-polysomnographic (VPSG) data administered the ADQ to 150 patients consecutively admitted to our Sleep and Epilepsy Centers for a follow-up visit. The final diagnosis, according to VPSG recordings of at least one major episode, classified patients either with DoA (DoA group) or with other sleep-related motor behaviors confounding for DoA (nDoA group). Results47 patients (31%) composed the DoA group; 56 patients with REM sleep behavior disorder, 39 with sleep-hypermotor epilepsy, six with night eating syndrome, and two with drug-induced DoA composed the nDoA group. The ADQ had a sensitivity of 72% (95% CI: 60–82) and a specificity of 96% (95% CI: 89–98) for DoA diagnosis; excluding the items regarding consciousness and episode recall, sensitivity was 83% (95% CI: 71–90) and specificity 93% (95% CI: 86–97). ConclusionsThe ADQ showed good accuracy in screening patients with DoA in a sleep and epilepsy center setting. Diagnostic criteria related to cognition and episode recall reduced ADQ sensitivity, therefore a better definition of these criteria is required, especially in adults.

Botulinum Toxin Therapy for Managing Sleep Bruxism: A Randomized and Placebo-Controlled Trial.

The purpose of this study is to evaluate the effects of botulinum toxin type A (BoNT-A) for managing sleep bruxism (SB) in a randomized, placebo-controlled trial. Thirty SB subjects were randomly assigned into two groups evenly. The placebo group received saline injections into each masseter muscle, and the treatment group received BoNT-A injections into each masseter muscle. Audio–video–polysomnographic recordings in the sleep laboratory were made before, at four weeks after, and at 12 weeks after injection. Sleep and SB parameters were scored according to the diagnostic and coding manual of American Academy of Sleep Medicine. The change of sleep and SB parameters were investigated using repeated measures analysis of variance (RM-ANOVA). Twenty-three subjects completed the study (placebo group 10, treatment group 13). None of the SB episode variables showed a significant time and group interaction (p > 0.05) except for electromyography (EMG) variables. The peak amplitude of EMG bursts during SB showed a significant time and group interaction (p = 0.001). The injection decreased the peak amplitude of EMG bursts during SB only in the treatment group for 12 weeks (p < 0.0001). A single BoNT-A injection cannot reduce the genesis of SB. However, it can be an effective management option for SB by reducing the intensity of the masseter muscle.

Searching food during the night: the role of video-polysomnography in the characterization of the night eating syndrome

ObjectivesTo describe the video-polysomnographic (VPSG) features of the night eating syndrome (NES), exploring the existence of potential subtypes. MethodsIn this study, 20 consecutive patients with NES according to the most recent diagnostic criteria underwent an overnight VPSG. None of them presented with a sleep-related eating disorder (SRED). VPSG recordings were reviewed identifying all eating episodes. For each episode, eating latency (time delay from awakening to food intake), eating duration (time between eating onset to eating offset) and sleep latency after eating offset (time delay from eating offset to sleep) were calculated. Total episode duration was considered as the time between awakening and sleep latency after eating offset. ResultsTen patients fulfilled the A1 core criterion for NES (evening hyperphagia with consumption of at least 25% of the daily caloric intake after the evening meal); within this group, eight patients also fulfilled the A2 criterion (at least two episodes of nocturnal eating per week) and were thus included in the evening hyperphagia (EH) subgroup. The remaining 10 patients satisfied only the A2 core criterion for NES, constituting the nocturnal ingestion (NI) subgroup. We recorded 20 eating episodes, seven in the EH group and 13 in the NI group. In the EH subgroup, three eating episodes occurred before sleep onset, one after an awakening from non-rapid eye movement (NREM) stage 1 sleep, two from NREM stage 2 and one from REM sleep. All 13 NI episodes occurred after an awakening from sleep (1 from NREM stage 1 sleep, 8 from NREM stage 2 and four from NREM stage 3). In EH patients, eating latency, total episode duration and sleep latency after eating offset were significantly longer than in NI patients. ConclusionOur VPSG data from a case series of 20 patients referred to our center for nocturnal eating indicate potential different NES subtypes. This distinction may have an impact on patients’ treatment and follow-up.

Sleep in Mowat-Wilson Syndrome: a clinical and video-polysomnographic study

ObjectiveSleep disturbances are frequently reported in Mowat-Wilson Syndrome (MWS). The current study aimed to evaluate clinical and video-polysomnographic (VPSG) characteristics of the sleep architecture and abnormal electroencephalogram (EEG) patterns during sleep in MWS. MethodsSixteen individuals with MWS (range 16 months–25 years), attending the Department of Child Neurology and Psychiatry of the University of Bologna, were included. The “Sleep Disturbances Scale for Children (SDSC)” questionnaire was administered to all parents of MWS patients, and all patients underwent a VPSG recording. ResultsThe analysis of the SDSC questionnaire revealed disturbances mainly at the sleep–wake transition and in initiating and maintaining sleep. Evaluation of sleep structure in MWS patients showed a significant reduction of total sleep time, an increase of wake after sleep onset and arousal index as compared to normal controls. An EEG pattern characterized by slowing of background activity and poverty of physiological sleep characterisitcs was observed in all patients. Moreover, in patients aged >7 years, anteriorly predominant spike and waves were observed, markedly activated by sleep configuring a sub-continuous or continuous activity. ConclusionOur data (both clinical and VPSG) documented the presence of significant and clinically relevant sleep disturbances in MWS patients. Moreover, we identified a characteristic age-dependent sleep EEG pattern that could provide a new element to assist in the management of MWS.

CHRNA2 and Nocturnal Frontal Lobe Epilepsy: Identification and Characterization of a Novel Loss of Function Mutation.

Mutations in genes coding for subunits of the neuronal nicotinic acetylcholine receptor (nAChR) have been involved in familial sleep-related hypermotor epilepsy (also named autosomal dominant nocturnal frontal lobe epilepsy, ADNFLE). Most of these mutations reside in CHRNA4 and CHRNB2 genes, coding for the α4 and β2 nAChR subunits, respectively. Two mutations with contrasting functional effects were also identified in the CHRNA2 gene coding for the α2 subunit. Here, we report the third mutation in the CHRNA2, found in a patient showing ADNFLE. The patient was examined by scalp EEG, contrast-enhanced brain magnetic resonance imaging (MRI), and nocturnal video-polysomnographic recording. All exons and the exon-intron boundaries of CHRNA2, CHRNA4, CHRNB2, CRH, KCNT1 were amplified and Sanger sequenced. In the proband, we found a c.754T>C (p.Tyr252His) missense mutation located in the N-terminal ligand-binding domain and inherited from the mother. Functional studies were performed by transient co-expression of α2 and α2Tyr252His, with either β2 or β4, in human embryonic kidney (HEK293) cells. Equimolar amounts of subunits expression were obtained by using F2A-based multi-cistronic constructs encoding for the genes relative to the nAChR subunits of interest and for the enhanced green fluorescent protein. The mutation reduced the maximal currents by approximately 80% in response to saturating concentrations of nicotine in homo- and heterozygous form, in both the α2β4 and α2β2 nAChR subtypes. The effect was accompanied by a strong right-shift of the concentration-response to nicotine. Similar effects were observed using ACh. Negligible effects were produced by α2Tyr252His on the current reversal potential. Moreover, binding of (±)-[3H]Epibatidine revealed an approximately 10-fold decrease of both Kd and Bmax (bound ligand in saturating conditions), in cells expressing α2Tyr252His. The reduced Bmax and whole-cell currents were not caused by a decrease in mutant receptor expression, as minor effects were produced by α2Tyr252His on the level of transcripts and the membrane expression of α2β4 nAChR. Overall, these results suggest that α2Tyr252His strongly reduced the number of channels bound to the agonist, without significantly altering the overall channel expression. We conclude that mutations in CHRNA2 are more commonly linked to ADNFLE than previously thought, and may cause a loss-of-function phenotype.

Sleep phenotypes in attention deficit hyperactivity disorder

ObjectiveA case-control study was performed to test the hypothesis that children with attention deficit hyperactivity disorder (ADHD) have chronic sleep deprivation and may be classified into specific sleep-related phenotypes. MethodsThirty outpatients with ADHD (nine females, mean age 10.1 ± 2.1 years) were recruited consecutively, and given a comprehensive sleep assessment, including blood exams, sleep questionnaires, laboratory video-polysomnographic recordings (v-PSG), multiple sleep latency tests, and one-week actigraphy. The PSG parameters were compared to those of 25 age-matched controls (12 females, mean age 10.34 ± 1.54 years) who underwent only the v-PSG. ResultsADHD children were classified as follows: a narcolepsy-like phenotype was found in four; delayed sleep onset insomnia in five; obstructive sleep apnea (OSA) in 15; periodic limb movements in eight, and sleep epileptiform discharges in 10 children. All subjects had a total sleep time shorter than 9 h at actigraphy, ferritin levels lower than 60 mcg/L, and a history of sleep problems (mainly OSA and insomnia). Compared to controls, the ADHD group had a higher apnea-hypopnea index at PSG. ConclusionsA full sleep assessment in children with ADHD confirmed the validity of the sleep phenotypes hypothesis, and revealed a much higher percentage of sleep problems than that found in the literature. Beyond the sleep phenotypes, all children reported a history of sleep problems and slept less than 9 h per night, indicating chronic sleep deprivation that should be evaluated as a possible unifying marker of ADHD.

REM sleep without atonia with REM sleep-related motor events: broadening the spectrum of REM sleep behavior disorder.

To assess the presence of increased REM-related motor activity during sleep, by questionnaires for REM sleep behavior disorder (RBD), in participants with "isolated" REM sleep without atonia (RWA). Two hundred forty-nine patients were consecutively enrolled, with age ≥18 years, sharing bedroom with a roommate, and without a severe health, neurological, or cognitive problem. Motor activity during sleep was assessed by means of the RBD Screening Questionnaire (RBDSQ) and the RBD questionnaire-Hong Kong (RBDQ-HK). A video-polysomnographic recording was obtained and the REM Atonia Index was computed. Thirteen participants were diagnosed to have RBD while the remaining 236 were subdivided into two subgroups: 34 participants with "low" (<0.8) and 202 participants with "high" Atonia Index (≥0.8). RBDSQ and RBDQ-HK were both higher in participants with low Atonia Index than in those with high Atonia Index, as well as number of drugs taken and number of comorbidities. No effect of antidepressant use was found on Atonia Index and a multiple-regression analysis showed that Atonia Index was significantly (inversely) correlated only with the behavioral score obtained with the RBDQ-HK. Our study shows that individuals with isolated RWA have an increased motor activity/behavioral pattern during sleep, although this activity does not allow us to diagnose RBD. Our findings broaden the spectrum of RBD and the condition that we have identified should be better characterized in order to understand its eventual development into fully blown RBD or not.

0679 Impaired Visual Processing In Rbd Patients: A Visual Search Task Study

Rapid Eye Movement (REM) sleep Behavior Disorder (RBD) is a REM sleep parasomnia known to be strongly associated with the development of neurodegenerative disorders. Cognitive deterioration has been shown to be a common issue in RBD patients, in particular impairments in visuo-spatial abilities. However, little is known about the effect of RBD on visual processing. The aim of this study was to evaluate the basic mechanisms of stimulus analysis in RBD patients by a visual search paradigm. 12 RBD patients (mean age: 68.25 ± 9.63, 9 males) and 12 age-matched healthy controls (HC) were enrolled in the study. After a nocturnal video-polysomnographic recording, patients performed a visual search task in which they had to detect the presence/absence of a target (letter T) embedded in the 50% of trials into a set of distractors (letters Os, Xs, or Ls). Target’s salience and distractors’ numerosity were manipulated as independent variables, whereas accuracy and reaction times (RT) were recorded as dependent variables. Typical effects of visual search were confirmed: RT increased with distractors’ number and decreased with targets’ salience. RBD patients showed significantly slower RT in comparison with HC. Furthermore, analyzing RT of stimuli containing the target in comparison to RT of stimuli in which the target was absent, patients differed from controls only in the condition of target absent. This result indicates a perceptual impairment specifically related to the exhaustive visual analysis, according to the Sternberg’s model. These results experimentally demonstrates a perceptual impairment revealed by the more demanding conditions of the visual search task. This impairment seems to be in line with previous neuropsychological researches that showed the presence of a visuo-spatial deficit in RBD patients. none.

Specific motor patterns of arousal disorders in adults: a video-polysomnographic analysis of 184 episodes

ObjectiveTo compile an objective accurate description of the motor patterns of adult arousal disorders (ADs). MethodsWe reviewed 59 nocturnal video-polysomnographic (VPSG) recordings of 30 adult patients (>15 years) with a history of sleepwalking (SW). We scrutinized the semeiology of all 184 episodes recorded, classifying them into three groups according to three semeiological motor patterns characterized by increasing intensity and complexity: simple arousal movements (pattern I), characterized by head flexion/extension, head flexion/extension and limb movement or head flexion/extension and partial trunk flexion/extension; rising arousal movements (pattern II), characterized by a complete trunk flexion with patient sitting up in bed; and complex arousal with ambulatory movements (pattern III) characterized by SW. The VPSG recordings were compared to those of 10 healthy controls. ResultsAD patients presented with 169 pattern I, 37 pattern II, and nine pattern III episodes. Pattern I developed into pattern II in 17 cases and into pattern II followed by pattern III in five patients. Pattern II developed into pattern III in four patients. Onset was abrupt in 55% of the episodes. Episodes lasted a mean (±standard deviation) of 33 ± 35 s. Movements tended to halt temporarily during 72% of the episodes. We recorded 248 movements during sleep in the healthy controls, none of whom presented with AD patterns. ConclusionWe identified three specific motor patterns in AD patients not previously reported and not observed in healthy controls. Identification of these patterns could be important for diagnosis and serve as the basis for a new definition of AD in adults.

Rationale for an adjunctive therapy with fenofibrate in pharmacoresistant nocturnal frontal lobe epilepsy

Nocturnal frontal lobe epilepsy (NFLE) is an idiopathic partial epilepsy with a family history in about 25% of cases, with autosomal dominant inheritance (autosomal dominant NFLE [ADNFLE]). Traditional antiepileptic drugs are effective in about 55% of patients, whereas the rest remains refractory. One of the key pathogenetic mechanisms is a gain of function of neuronal nicotinic acetylcholine receptors (nAChRs) containing the mutated α4 or β2 subunits. Fenofibrate, a common lipid-regulating drug, is an agonist at peroxisome proliferator-activated receptor alpha (PPARα) that is a ligand-activated transcription factor, which negatively modulates the function of β2-containing nAChR. To test clinical efficacy of adjunctive therapy with fenofibrate in pharmacoresistant ADNFLE\NFLE patients, we first demonstrated the effectiveness of fenofibrate in a mutated mouse model displaying both disease genotype and phenotype. We first tested the efficacy of fenofibrate in transgenic mice carrying the mutation in the α4-nAChR subunit (Chrna4S252F) homologous to that found in humans. Subsequently, an add-on protocol was implemented in a clinical setting and fenofibrate was administered to pharmacoresistant NFLE patients. Here, we show that a chronic fenofibrate diet markedly reduced the frequency of large inhibitory postsynaptic currents (IPSCs) recorded from cortical pyramidal neurons in Chrna4S252F mice, and prevented nicotine-induced increase of IPSC frequency. Moreover, fenofibrate abolished differences between genotypes in the frequency of sleep-related movements observed under basal conditions. Patients affected by NFLE, nonresponders to traditional therapy, by means of adjunctive therapy with fenofibrate displayed a reduction of seizure frequency. Furthermore, digital video-polysomnographic recordings acquired in NFLE subjects after 6months of adjunctive fenofibrate substantiated the significant effects on control of motor-behavioral seizures. Our preclinical and clinical studies suggest PPARα as a novel disease-modifying target for antiepileptic drugs due to its ability to regulate dysfunctional nAChRs.

Proton MR Spectroscopy in Patients With Sleep-Related Hypermotor Epilepsy (SHE): Evidence of Altered Cingulate Cortex Metabolism.

To identify structural and/or metabolic alterations in patients with sleep-related hypermotor epilepsy (SHE) using magnetic resonance imaging (MRI) and proton MR spectroscopy (1H-MRS). Nineteen SHE patients (seven males; 34.7 ± 9.7 years, mean age ± standard deviation) and 17 matched healthy volunteers (seven males; 34.0 ± 8.9 years) were included in the study. In all patients, the diagnosis of SHE was confirmed by video-polysomnographic recording of seizures. Semiology, seizure frequency, and therapy were assessed for all patients. For each recruited participant, structural MRI and 1H-MRS sequences were acquired. 1H-MRS was performed on two regions of interest: the medial thalamus and the anterior cingulate gyrus. At examination, five patients were seizure free. In the remainder, seizure frequency ranged from yearly to multiple episodes per night. Brain MRI was normal in all patients but one. The ratio of N-acetyl-aspartate/Creatine (NAA/Cr) was significantly reduced in the anterior cingulate cortex in patients compared to controls (p < .05). Thalamic NAA/Cr showed no differences between patients and controls. Regression analysis showed that NAA/Cr in the anterior cingulate gyrus correlated with seizure frequency (p < .05), being lower in patients with higher seizure frequency. Given the absence of structural MR changes, our 1H-MRS data point to a functional NAA reduction in the cingulate cortex of SHE patients, more severe in those patients with higher seizure frequency and thus supporting the involvement of the anterior mesial structures in the pathophysiology of SHE.

Modulation of the Muscle Activity During Sleep in Cervical Dystonia.

Impaired sleep has been reported as an important nonmotor feature in dystonia, but so far, self-reported complaints have never been compared with nocturnal video-polysomnographic (PSG) recording, which is the gold standard to assess sleep-related disorders. Twenty patients with idiopathic isolated cervical dystonia and 22 healthy controls (HC) underwent extensive clinical investigations, neurological examination, and questionnaire screening for excessive daytime sleepiness and sleep-related disorders. A full-night video PSG was performed in both patients and HC. An ad hoc montage, adding electromyographic leads over the muscle affected with dystonia, was used. When compared to controls, patients showed significantly increased pathological values on the scale assessing self-reported complaints of impaired nocturnal sleep. Higher scores of impaired nocturnal sleep did not correlate with any clinical descriptors but for a weak correlation with higher scores on the scale for depression. On video-PSG, patients had significantly affected sleep architecture (with decreased sleep efficiency and increased sleep latency). Activity over cervical muscles disappears during all the sleep stages, reaching significantly decreased values when compared to controls both in nonrapid eye movements and rapid eye movements sleep. Patients with cervical dystonia reported poor sleep quality and showed impaired sleep architecture. These features however cannot be related to the persistence of muscle activity over the cervical muscles, which disappears in all the sleep stages, reaching significantly decreased values when compared to HC.

MEIS1 variant as a determinant of autonomic imbalance in Restless Legs Syndrome

Restless Legs Syndrome (RLS) is a genetically complex neurological disorder in which overlapping genetic risk factors may contribute to the diversity and heterogeneity of the symptoms. The main goal of the study was to investigate, through analysis of heart rate variability (HRV), whether in RLS patients the MEIS1 polymorphism at risk influences the sympathovagal regulation in different sleep stages. Sixty-four RLS patients with periodic leg movement index above 15 per hour, and 38 controls underwent one night of video-polysomnographic recording. HRV in the frequency- and time- domains was analyzed during nighttime sleep. All RLS patients were genotyped, and homozygotes for rs2300478 in the MEIS1 locus were used for further analysis. Comparison of the sympathovagal pattern of RLS patients to control subjects did not show significant differences after adjustments for confounding factors in frequency-domain analyses, but showed an increased variability during N2 and N3 stages in time-domain analyses in RLS patients. Sorting of RLS patients according to MEIS1 polymorphism reconfirmed the association between MEIS1 and PLMS, and showed a significant increased sympathovagal balance during N3 stage in those homozygotes for the risk allele. RLS patients should be considered differently depending on MEIS1 genotype, some being potentially at risk for cardiovascular disorders.

Sleep architecture in insomniacs with severe benzodiazepine abuse

Benzodiazepines (BZDs) are the most commonly prescribed compounds in insomnia. A long-term of BZDs use may cause dependence and abuse. The aim of this study was to evaluate sleep architecture and microstructure (in terms of cyclic alternating pattern - CAP - analysis and of sleep EEG power spectral analysis) in a group of long-term users of high doses of BZDs for their primary chronic insomnia. Twenty patients consecutively admitted at the Sleep Centre for drug discontinuation and 13 matched healthy controls underwent a full nocturnal video-polysomnographic recording, after one adaptation night. Significant differences were found in time in bed, REM sleep latency and sleep stage 1% which were increased in patients compared to controls, while CAP rate was dramatically decreased. During NREM sleep, patients showed a clear decrease in the relative power of delta band. Our data demonstrate that in adults with chronic insomnia, long-term use of high doses of BZDs induces a severe disruption of sleep microstructure, while sleep architecture seems to be much less affected. The long term use of high doses of BZDs for chronic insomnia induces a marked depression of slow wave activity and of its physiological instability.

Comparison Between Automatic and Visual Scorings of REM Sleep Without Atonia for the Diagnosis of REM Sleep Behavior Disorder in Parkinson Disease

To compare three different methods, two visual and one automatic, for the quantification of rapid eye movement (REM) sleep without atonia (RSWA) in the diagnosis of REM sleep behavior disorder (RBD) in Parkinson's disease (PD) patients. Sixty-two consecutive patients with idiopathic PD underwent video-polysomnographic recording and showed more than 5 minutes of REM sleep. The electromyogram during REM sleep was analyzed by means of two visual methods (Montréal and SINBAR) and one automatic analysis (REM Atonia Index or RAI). RBD was diagnosed according to standard criteria and a series of diagnostic accuracy measures were calculated for each method, as well as the agreement between them. RBD was diagnosed in 59.7% of patients. The accuracy (85.5%), receiver operating characteristic (ROC) area (0.833) and Cohen's K coefficient (0.688) obtained with RAI were similar to those of the visual parameters. Visual tonic parameters, alone or in combination with phasic activity, showed high values of accuracy (93.5-95.2%), ROC area (0.92-0.94), and Cohen's K (0.862-0.933). Similarly, the agreement between the two visual methods was very high, and the agreement between each visual methods and RAI was substantial. Visual phasic measures alone performed worse than all the other measures. The diagnostic accuracy of RSWA obtained with both visual and automatic methods was high and there was a general agreement between methods. RAI may be used as the first line method to detect RSWA in the diagnosis of RBD in PD, together with the visual inspection of video-recorded behaviors, while the visual analysis of RSWA might be used in doubtful cases.