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Background: In 2007, the AASM Manual for the Scoring of Sleep and Associated Events was published by the American Academy of Sleep Medicine (AASM). Concerning the visual classification of sleep stages, these new rules are intended to replace the rules by Rechtschaffen and Kales (R&K). Methods: We adapted the automatic R&K sleep scoring system Somnolyzer 24 × 7 to comply with the AASM rules and subsequently performed a validation study based on 72 polysomnographies from the Siesta database (56 healthy subjects, 16 patients, 38 females, 34 males, aged 21-86 years). Scorings according to the AASM rules were performed manually by experienced sleep scorers and semi-automatically by the AASM version of the Somnolyzer. Manual scorings and Somnolyzer reviews were performed independently by at least 2 out of 8 experts from 4 sleep centers. Results: In the quality control process, sleep experts corrected 4.8 and 3.7% of the automatically assigned epochs, resulting in a reliability between 2 Somnolyzer-assisted scorings of 99% (Cohen's kappa: 0.99). In contrast, the reliability between the 2 manual scorings was 82% (kappa: 0.76). The agreement between the 2 Somnolyzer-assisted and the 2 visual scorings was between 81% (kappa: 0.75) and 82% (kappa: 0.76). Conclusion: The AASM version of the Somnolyzer revealed an agreement between semi-automated and human expert scoring comparable to that published for the R&K version with a validity comparable to that of human experts, but with a reliability close to 1, thereby reducing interrater variability as well as scoring time to a minimum. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objectives: Sleep bruxism (SB) is a parasomnia defined as a stereotyped movement disorder characterized by grinding or clenching of the teeth during sleep. Pathophysiologically, SB is the result of biological and psychosocial influences. Treatment comprises behavioral, orthodontic and pharmacological interventions. While benzodiazepines and muscle relaxants have been reported by clinicians to reduce bruxism-related motor activity, placebo-controlled studies are lacking. Thus, the aim of the present study was to investigate the acute effects of clonazepam (Rivotril®) as compared with placebo, utilizing polysomnography and psychometry. Method: Ten drug-free outpatients (6 females, 4 males), aged 46.5 ± 13.1 years, suffering from SB (ICD-10: F45.8; ICSD: 306.8) and having been treated by bite splints were included in the trial. Comorbidity was high: 7 patients presented nonorganic insomnia related to adjustment or anxiety disorders (5 patients) or depression (2 patients); all patients had a concomitant movement disorder (6 restless legs syndrome, 4 periodic leg movement disorder). After one adaptation night, patients received placebo and 1 mg clonazepam 1/2 hour before lights out in a single-blind, nonrandomized study design. Objective sleep quality was determined by polysomnography, subjective sleep and awakening quality by rating scales, objective awakening quality by psychometric tests. Clinical evaluation was based on the Pittsburgh Sleep Quality Index (PSQI), the Zung Depression (SDS) and Anxiety (SAS) Scales, the Quality of Life Index, the Epworth Sleepiness Scale and the International Restless Legs Syndrome Study Group (IRLSSG) Scale. Results: On admission, SB patients exhibited deteriorated PSQI, SAS, SDS and IRLSSG measures. As compared with placebo, 1 mg clonazepam significantly improved the mean bruxism index from 9.3 to 6.3/h of sleep. Furthermore, it significantly improved the total sleep period, total sleep time, sleep efficiency, sleep latency and time awake during the total sleep period, and increased stage 2 sleep and movement time. Periodic leg movements decreased significantly, while the apnea index and apnea-hypopnea index increased marginally, but remained within normal limits. Subjective sleep quality improved as well, while in mood, performance and psychophysiology no changes were observed. Conclusion: Acute clonazepam therapy significantly improved not only the bruxism index but also objective and subjective sleep quality, with unchanged mood, performance and psychophysiological measures upon awakening, suggesting good tolerability of the drug. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

To date, the only standard for the classification of sleep-EEG recordings that has found worldwide acceptance are the rules published in 1968 by Rechtschaffen and Kales. Even though several attempts have been made to automate the classification process, so far no method has been published that has proven its validity in a study including a sufficiently large number of controls and patients of all adult age ranges. The present paper describes the development and optimization of an automatic classification system that is based on one central EEG channel, two EOG channels and one chin EMG channel. It adheres to the decision rules for visual scoring as closely as possible and includes a structured quality control procedure by a human expert. The final system (Somnolyzer 24 × 7™) consists of a raw data quality check, a feature extraction algorithm (density and intensity of sleep/wake-related patterns such as sleep spindles, delta waves, SEMs and REMs), a feature matrix plausibility check, a classifier designed as an expert system, a rule-based smoothing procedure for the start and the end of stages REM, and finally a statistical comparison to age- and sex-matched normal healthy controls (Siesta Spot Report™). The expert system considers different prior probabilities of stage changes depending on the preceding sleep stage, the occurrence of a movement arousal and the position of the epoch within the NREM/REM sleep cycles. Moreover, results obtained with and without using the chin EMG signal are combined. The Siesta polysomnographic database (590 recordings in both normal healthy subjects aged 20–95 years and patients suffering from organic or nonorganic sleep disorders) was split into two halves, which were randomly assigned to a training and a validation set, respectively. The final validation revealed an overall epoch-by-epoch agreement of 80% (Cohen’s kappa: 0.72) between the Somnolyzer 24 × 7 and the human expert scoring, as compared with an inter-rater reliability of 77% (Cohen’s kappa: 0.68) between two human experts scoring the same dataset. Two Somnolyzer 24 × 7 analyses (including a structured quality control by two human experts) revealed an inter-rater reliability close to 1 (Cohen’s kappa: 0.991), which confirmed that the variability induced by the quality control procedure, whereby approximately 1% of the epochs (in 9.5% of the recordings) are changed, can definitely be neglected. Thus, the validation study proved the high reliability and validity of the Somnolyzer 24 × 7 and demonstrated its applicability in clinical routine and sleep studies. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Utilizing polysomnography (PSG) and psychometry, objective and subjective sleep and awakening quality was investigated in 11 patients (mean age 50 ± 14) with nonorganic insomnia (F 51.0) related to dysthymia (F 34.1) as compared with 11 age- and sex-matched normal controls. Patients demonstrated decreased sleep efficiency and sleep stage S2 as well as increased sleep latency to S1, S2 and S3, wakefulness within the total sleep period, number of awakenings, S1 and REM sleep. There was no intergroup difference in REM latency. Subjective sleep quality and the total score of the Self-Assessment Scale for Sleep and Awakening Quality (SSA) were deteriorated as were evening and morning well-being, mood, affectivity and drowsiness. Noopsychic measures showed deteriorated numerical memory, fine motor activity and reaction time variability. In a placebo-controlled crossover design study, the acute effects of 100 mg trazodone[sup 1] , a serotonin reuptake inhibitor with a sedative action due to 5HT[sub 2] and α[sub 1] receptor blockade, were investigated in the patients. As compared with placebo, trazodone induced an increase in slow-wave sleep (S3 + 4), a lengthening of REM latency, a decrease in REM sleep and a normalization of the periodic leg movement (PLM) index. In the morning, there was a minimal increase in somatic complaints and a decrease in critical flicker frequency and systolic blood pressure. In conclusion, our study demonstrated that dysthymia induced significant changes in objective and subjective sleep and awakening quality, which were counteracted by 100 mg trazodone, thus suggesting a key-lock principle in the treatment of nonorganic insomnia related to dysthymia with this drug.Copyright © 2001 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]