Periodic limb movements both in non-REM and REM sleep: relationships between cerebral and autonomic activities.

Objective: To investigate the temporal relationship between cerebral and autonomic activities before and during periodic limb movements in NREM and REM sleep (PLMS).

Methods: Patterns of EEG, cardiac and muscle activities associated with PLMS were drawn from polysomnographic recordings of 14 outpatients selected for the presence of PLMS both in NREM and REM sleep. PLMS were scored during all sleep stages from tibial EMG.

Multicenter case-control study on restless legs syndrome in multiple sclerosis: the REMS study.

Study Objectives: To verify the existence of a symptomatic form of restless legs syndrome (RLS) secondary to multiple sclerosis (MS) and to identify possible associated risk factors.

Design: Prospective, multicenter, case-control epidemiologic survey.

Settings: Twenty sleep centers certified by the Italian Association of Sleep Medicine.

[Commuting accidents: the influence of excessive daytime sleepiness. A review of an Italian Police officers population].

Commuting accidents (CA) play an important role in many systems of workers' compensation insurance and with good reason, as they generally bring about more serious consequences in terms of permanent disablement and death than ordinary occupational accidents; this usually leads to high social costs. Nevertheless, research investigations aimed at studying the possible causes underlying the phenomenon are not available in medical literature. Objective of the present study is to evaluate whether excessive daytime sleepiness (EDS) might influence the occurrence of CA.

Sleep in the human hippocampus: a stereo-EEG study.

Background: There is compelling evidence indicating that sleep plays a crucial role in the consolidation of new declarative, hippocampus-dependent memories. Given the increasing interest in the spatiotemporal relationships between cortical and hippocampal activity during sleep, this study aimed to shed more light on the basic features of human sleep in the hippocampus.

Methodology/principal Findings: We recorded intracerebral stereo-EEG directly from the hippocampus and neocortical sites in five epileptic patients undergoing presurgical evaluations.

Insomnia in general practice : a consensus report produced by sleep specialists and primary-care physicians in Italy.

Insomnia is an extremely common condition with major social and economic consequences worldwide. Two large epidemiological studies (Morfeo 1 and Morfeo 2) recently performed in Italy provided much-needed novel data on the impact of insomnia in patients whose primary healthcare is provided by general practitioners (GPs). These studies found that insomnia is managed relatively well by GPs in Italy, although diagnosis and treatment can be compromised because of the lack of standardised criteria.

A model-based approach to homeostatic and ultradian aspects of nocturnal sleep structure in narcolepsy.

Study Objective: We present a mathematical model of sleep-EEG structure applied to the analysis of sleep patterns in narcoleptics by combining the 2-process model of sleep regulation and the reciprocal interaction model of REM regulation suggested by McCarley and Hobson. The aim was the individuation of parameters characterizing narcoleptic sleep in comparison to controls.

Design: Polysomnographic data were drawn from a previous study about sleep in narcolepsy.

Pre-symptomatic diagnosis in fatal familial insomnia: serial neurophysiological and 18FDG-PET studies.

Knowing how and when the degenerative process starts is important in neurodegenerative diseases. We have addressed this issue in fatal familial insomnia (FFI) measuring the cerebral metabolic rate of glucose (CMRglc) with 2-[18F]fluoro-2-deoxy-D-glucose PET in parallel with detailed clinical, neuropsychological examinations and polysomnography with EEG spectral analyses. Nine asymptomatic carriers of the D178N mutation, 10 non-carriers belonging to the same family, and 19 age-matched controls were studied over several years.

CAP and arousals are involved in the homeostatic and ultradian sleep processes.

There is growing evidence that cyclic alternating pattern (CAP) and arousals are woven into the basic mechanisms of sleep regulation. In the present study, the overnight sleep cycles (SC) of 20 normal subjects were analyzed according to their stage composition, CAP rate, phase A subtypes and arousals. Individual SC were then divided into 10 normalized temporal epochs.

Impairment of the production of delta sleep in anorectic adolescents.

Objective: Total sleep time and slow-wave sleep (SWS) are frequently reported to be reduced in anorectics. A preliminary study showed that slow-wave activity (SWA, 0.5-4.

Professional shift-work drivers who adopt prophylactic naps can reduce the risk of car accidents during night work.

Study Objectives: Night work can be dangerous because both circadian sleep propensity (process C) and sleep pressure due to the prolonged wakefulness (process S) contribute to the reduction of vigilance levels. As naps are a countermeasure to sleepiness, this study evaluates the role they play in preventing sleep-related accidents in Italian shift-working police drivers.

Design/setting/participants: The study concerns highway car accidents that occurred to Italian shift-working police drivers; it was performed in 2 steps: a retrospective analysis of the overall number of accidents that occurred during the years 1993--1997 (n, 1195), followed by a validation analysis of a smaller cohort of accidents prospectively collected during 2003 (n, 84).

Quantitative analysis of sleep EEG microstructure in the time-frequency domain.

A number of phasic events influence sleep quality and sleep macrostructure. The detection of arousals and the analysis of cyclic alternating patterns (CAP) support the evaluation of sleep fragmentation and instability. Sixteen polygraphic overnight recordings were visually inspected for conventional Rechtscaffen and Kales scoring, while arousals were detected following the criteria of the American Sleep Disorders Association (ASDA).

Is insomnia a neurophysiological disorder? The role of sleep EEG microstructure.

Unlike other sleep disorders, such as sleep-related breathing disorders and periodic limb movement (PLM), the nature and severity of which are quantified by specific respiratory and motor indexes, no apparent organ dysfunction underlies several cases of insomnia (in particular primary insomnia), which can be objectively diagnosed only through the structural alterations of sleep. Polysomnography (PSG) investigation indicates that insomnia is the outcome of a neurophysiological disturbance that impairs the regulatory mechanisms of sleep control, including sleep duration, intensity, continuity and stability. In particular, analysis of sleep microstructure has permitted to establish that etiologic factors of different nature (including depressive disorders) exert a common destabilizing action on sleep, which is reflected in an increase of cyclic alternating pattern (CAP) rate.

Changes in cerebral and autonomic activity heralding periodic limb movements in sleep.

Background And Purpose: Periodic limb movement disorder (PLMD) is frequently accompanied by awakenings or signs of EEG arousal. However, it is matter of debate whether EEG arousals trigger leg movements or both EEG arousal and leg movements are separate expressions of a common pathophysiological mechanism. Previous studies showed that cardiac and cerebral changes occur in association with periodic limb movements (PLMs), and that a combining increase in delta activity and in heart rate (HR) occurs before the onset of PLMs.

Modifications of sleep EEG induced by chronic vagus nerve stimulation in patients affected by refractory epilepsy.

Objective: The aim of this study was to evaluate the impact of chronic vagus nerve stimulation (VNS) on sleep/wake background EEG and interictal epileptiform activity (IEA) of patients with medically refractory epilepsy.

Methods: From a broader sample of 10 patients subjected to baseline and treatment polysomnographies, spectral analysis and IEA count have been performed on 6 subjects' recordings, comparing the results by means of statistical analysis.

Results: An overall increase in EEG total power after VNS has been observed, more marked in NREM sleep; collapsing EEG power spectra into 5 frequency bands, we have found a statistically significant increase in delta and theta in NREM sleep, and of alpha in wakefulness and REM sleep.

[Shift-work seniority increases the severity of sleep disorders. Comparison of different categories of shift-workers].

Shift-work disrupts the sleep-wake cycle and could bring about sleep disorders and excessive daytime sleepiness. We studied two samples of shift-workers, a group of 178 nurses and one of 174 police officers, all working in the town of Palermo (Italy); their answers to a sleep disorder questionnaire were scored and added in order to create a Sleep Disorder Score (SDS). The SDS cut-off value, discrimining pathological values from physiological ones, was settled a-priori.

Prevalence of patent foramen ovale in subjects with obstructive sleep apnea: a transcranial Doppler ultrasound study.

Background: Under particular conditions a patent foramen ovale (PFO) can potentially give rise to ischemic stroke by means of paradoxic embolization. In obstructive sleep apnea syndrome (OSAS) right to left shunting (RLSh) can occur through PFO during periods of nocturnal apnea. Our study aimed to evaluate the prevalence of PFO diagnosed by means of transcranial Doppler (TcD) in subjects with OSAS.

Sleepiness in a population of Italian shiftwork policemen.

The aim of this study was to evaluate the effects of shiftwork on sleepiness, sleep disorders and sleep related accidents in a population of policemen. Data concerning age and physical characteristics, working conditions, sleep problems and accidents were collected by a questionnaire. Sleepiness was evaluated by the Epworth Sleepiness Scale (ESS) while the presence of sleep disorders was evaluated by a score (SD-score) drawn from indicators of insomnia, breathing disorders, periodic limb movements-restless leg syndrome and hypersomnia.

Chronic vagus nerve stimulation improves alertness and reduces rapid eye movement sleep in patients affected by refractory epilepsy.

Objective: Our study aimed to evaluate the existence and entity of changes in sleep structure following vagus nerve stimulation in patients with refractory epilepsy.

Method: A polysomnographic study was performed on the nocturnal sleep of 10 subjects with refractory epilepsy. Subjects were recorded both in baseline conditions and after chronic vagus nerve stimulation.

Emotional information processing in patients with narcolepsy: a psychophysiologic investigation.

Objectives: Cataplexy is the key symptom of the narcoleptic syndrome. It is usually triggered by emotions, which play an important role in the manifestation and severity of the disease. Accordingly, we compared the psychophysiologic effects on patients with narcolepsy and healthy subjects of processing visual stimuli that have established emotional valences.

Obstructive sleep apnea can be provocative for right-to-left shunting through a patent foramen ovale.

Study Objectives: Under particular conditions, a patent foramen ovale (PFO) can potentially give rise to ischemic stroke by means of paradoxical embolization, due to right-to-left shunt. Our study aimed to evaluate the presence of right-to-left shunt in patients with obstructive sleep apnea syndrome (OSAS) and diagnosed PFO during sleep.

Design And Setting: Assessment of provocative-only PFO and concomitant OSAS.

Does the prion protein gene 129 codon polymorphism influence sleep? Evidence from a fatal familial insomnia kindred.

Objective: Experimental and clinical evidence in prion diseases suggests that the prion protein gene (PRNP) plays a role in regulating sleep.

Methods: Seventeen healthy individuals belonging to a single fatal familial insomnia pedigree, 8 carriers and 9 non-carriers of the PRNP codon 178 mutation, underwent polysomnography and spectral electroencephalographic (EEG) analysis. All were also characterized with regard to the codon 129 polymorphism on both PRNP alleles.

Sleep disorders and daytime sleepiness in state police shiftworkers.

Police, who work shifts, participate in both risky and delicate tasks. The authors investigated sleep habits, prevalence of sleep disorders, sleepiness on the job, and hypnotic drug intake (Benzodiazepines, Zaleplon, Zolpidem, or Zoplicone) in a population of Italian state police officers. This study was conducted with self-administered questionnaires.

Nocturnal sleep features in narcolepsy: a model-based approach.

The internal structure of night sleep in subjects with narcolepsy significantly differs as compared to the controls. The differences consist in the presence of sleep onset REM periods (SOREMPs) and in a longer duration (120 minutes versus 90 minutes) of the NREM-REM cycles. Another difference consists in the lack of increase in REM sleep duration during the night, cycle after cycle.

Brain function and effects of shift work: implications for clinical neuropharmacology.

Night or shift work is to a relevant extent unavoidable, suits a growing preference for flexibility and is predicted to spread. However, a significant percentage of shift workers report discomfort or health problems and they often (15-20% of cases) move to different occupations. Apart from social implications, the issue has medical and scientific relevance, with evidence suggesting that the circadian rhythm phases are neither equivalent nor interchangeable with respect to function and performance.

Sleep related vehicle accidents on Italian highways.

Sleepiness has been identified as a significant risk factor for vehicle accidents, and specific surveys are needed for Italy. The aim of this study was to assess incidence and characteristics of sleep-related vehicle-crashes on Italian highways. The database of the Italian National Institute of Statistics (1993-1997) was the source for the survey (50859 accidents with 1632 (3.