Somnologie

Translationale Schlafmedizin

Evaluation des Zungengrunds bei OSAS unter elektrischer Stimulationstherapie des N. hypoglossus Zusammenfassung Hintergrund Die nächtliche elektrische Stimulationstherapie des Nervus hypoglossus von Patienten mit obstruktivem Schlafapnoesyndrom (OSAS) ist eine vergleichsweise junge Therapieform. Verlaufsdaten zu Auswirkungen auf die Zungengrundmorphologie unter langfristiger Stimulationstherapie liegen nicht vor. Fragestellung Im Rahmen dieser Studie erfolgte die sonografische Evaluation der Zunge bei Patienten mit OSAS vor und nach der Implantation eines Hypoglossusstimulationssystems. Ziel war es, die Durchführbarkeit der Methode zu zeigen sowie erste Hinweise auf Veränderungen der Zungengrundmorphologie unter Therapie zu erhalten. Material und Methoden Bei sieben Patienten mit OSAS (m = 5, w = 2, 60,14 ± 12,5 J, Zeit unter Stimulationstherapie 296,43 ± 92,04 Tage) wurden vor und 12 Monate nach Implantation eines einseitigen Stimulationssystems des N. hypoglossus (ImThera Aura 6000™) mittels Ultraschall (GE Vivid S6, 4 MHz, Konvexsonde) die Zunge und der Zungengrund vermessen. Ergebnisse 12 Monate nach Implantation hatte sich die gemessene Distanz zwischen beiden Aa. linguales an ihrer Eintrittsstelle in den Zungengrund verringert (MW vor Implantation 3,844 ± 0,397 cm; MW nach 12 Monaten 3,591 ± 0,302; p = 0,037). Alle anderen Parameter wiesen keine statistisch auffällige Veränderung auf. Diskussion Ultraschall kann ein sinnvolles Hilfsmittel bei der Evaluation von Patienten mit OSAS sein. Die klinische Bedeutung der beobachteten Messwerte ist noch unklar. Eine langfristige Verkleinerung des Zungengrunddurchmessers durch die Stimulationstherapie scheint möglich zu sein.

Measurement of respiratory effort in sleep by 3D camera and respiratory inductance plethysmography Abstract Background Polysomnography systems used for the diagnosis of sleep respiratory disorders are comprised of multiple sensors, including abdomen and thorax respiratory inductance plethysmography (RIP) belts to record respiratory effort. However, RIP belts are known to be susceptible to signal loss. To resolve this, we utilized a contactless three-dimensional (3D) time-of-flight (TOF) camera to monitor respiratory effort. Objective We aimed to show that respiratory effort monitoring can be achieved by 3D TOF camera recording instead of RIP belts. Materials and methods The use of RIP belt signals is twofold. Firstly, the signals are used to classify the apnea events into obstructive, central, and mixed. Additionally, the American Academy of Sleep Medicine (AASM) Scoring Manual recommends the scoring of apneas and hypopneas using RIPSum (the sum of the abdomen and thorax RIP signals) when the airflow sensors are unavailable. We therefore used the 3D effort signal to classify apneas and compared it to the RIP signal classification. Reduced effort events from RIP and 3D effort signals were compared to the apnea and hypopnea events. Furthermore, the changes in effort during the events were compared between the two effort signals. Results Classification by 3D effort signal performed well, with 80% accuracy. It worked best for central apneas, with an accuracy of 99%. There was a high correlation of r = 0.88 (r ≠ 0, p = 0.0001) between the 3D effort signal events and RIPSum events. There was also a significant correlation of 0.62 (r ≠ 0, p = 0.0001) between 3D effort signal and RIPSum in the decrease of effort during apnea and hypopnea events. Conclusion We conclude that respiratory effort derived from a 3D TOF camera can be used as an alternative to RIP belts for scoring of apneas and hypopneas and classification of apneas.

Microstructure of cortical activity during sleep reflects respiratory events and state of daytime vigilance Abstract Background Besides visual sleep stage scoring, it is possible to separate sleep stages by analyzing spatially distributed three-channel electroencephalogram (EEG) root mean square (RMS) amplitudes. This approach allows qualitative and quantitative evaluation of sleep architecture. The aim of this study was to analyze the effect of apnea–hypopnea index (AHI) and state of vigilance on the microstructure of cortical activity during sleep using EEG cluster analysis. Materials and methods In 31 obstructive sleep apnea (OSA) patients, cortical EEG patterns were recorded during polysomnography and subjected to EEG cluster analysis. The results were subsequently correlated to AHI as well as to subjective (Epworth Sleepiness Scale) and objective (pupillographic sleepiness test) daytime sleepiness using linear regression. In 18/31 patients, cortical EEG patterns were recorded again the following night during continuous positive airway pressure (CPAP) titration and compared to the results of the first night. Results Linear regression analyses revealed dependencies of specific cortical EEG patterns on AHI (intra-cluster distance of N2 [p = 0.019], N3 [p = 0.024]; inter-cluster distance of wake-N2 [p = 0.046], wake-N3 [p = 0.047], N2–N3 [p = 0.021]) and on objective daytime sleepiness (wake intra-cluster distance [p = 0.047], inter-cluster distance of wake-N3 [p = 0.042]), but not on subjective daytime sleepiness. Specifically, an increase in EEG pattern variability was found in patients with high AHI values, which could be reduced by CPAP therapy. Conclusion This new approach enables objective analysis and visualization of sleep macro- and microstructure. The variance of neuronal EEG signal patterns enables conclusions on the presence of pathological respiratory events and objectively measured daytime sleepiness.

Restless legs syndrome in childhood and adolescence Abstract Background The prevalence of restless legs syndrome (RLS) is lower among children than adults. This could be due to RLS manifestation later in life or false diagnoses in children caused by symptom similarity to other diseases such as attention deficient hyperactivity disorder (ADHD). Objective The aim of this study was to test the reliability and validity of a questionnaire designed to identify RLS-related symptoms in children and adolescents. Materials and methods The questionnaire was designed for two age groups (6–12 and 13–18 years). It was distributed among 11 pediatric RLS patients and 22 healthy children and adolescents (control group). The control group answered the questionnaire twice (M1, M2; 14-day separation). Reliability was analyzed descriptively and with Spearman correlation coefficients, intraclass correlation coefficients (ICC), and test–retest variability (TRV). An index was calculated by transferring the 12 answers concerning RLS symptoms into a coding system, grading each answer between −2 and 2 and adding the grades to an index value. Low index values hint at the absence of RLS-related symptoms. Student's t‑test was used to test the difference between healthy controls and pediatric patients. Results In the control group, 84% of answer pairs were identical between M1 and M2. Mean TRV was 8% (range: 2–16%), Spearman correlation coefficient 0.762, and ICC 0.754 (confidence interval: 0.473–0.899). Comparison between controls and pediatric RLS patients showed that RLS patients had significantly higher (p < 0.001) index values (mean ± SD: 18.8 ± 4) compared to controls (mean ± SD: −3.8 ± 7.6). Conclusion The questionnaire can distinguish between supposedly healthy and RLS-diagnosed children and adolescents in most cases. Nonetheless, the questionnaire cannot be used alone as a diagnostic instrument.

Erklärung zu finanziellen und nichtfinanziellen Interessen in CME-Fortbildungen von Springer Medizin

Erfassung von tatsächlichem Schlafverhalten und Beschwerdesymptomatik mittels Selbstrating-Diagnostikfragebogen – eine Validierung anhand von Schlaftagebüchern Zusammenfassung Hintergrund In der klinischen Routine werden retrospektive Selbstbewertungsfragebögen zu schlafassoziierten Symptomen als diagnostisches Instrument eingesetzt, ihre tatsächliche Validität ist bisher dennoch kaum untersucht. Auch ein aus dem Diagnostikfragebogen gebildeter Schlafqualitätsindex könnte dem Schlafmediziner einen schnellen Zugang zur weiteren spezifischen Anamnese ermöglichen. Fragestellung Es wurde überprüft, ob ein Diagnostikfragebogen, welcher eigens im Schlaflabor entwickelt wurde, sowie ein daraus abgeleiteter Schlafqualitätsindex valide Abbildungen von Schlafgewohnheiten und Beschwerdesymptomatik bei Patienten mit schlafbezogener Atmungsstörung (SBAS) darstellen. Material und Methode Von 326 Patienten mit Verdacht auf SBAS wurden ein zweiwöchiges Schlaftagebuch sowie ein Diagnostikfragebogen bearbeitet, welcher das Schlafverhalten der vorangegangenen vier Wochen erfasste. Mittels schrittweiser generalisierter linearer Regressionen wurde untersucht, ob die Angaben des Fragebogens korrespondierende Angaben des Tagebuchs vorhersagen. Ein aus dem Diagnostikfragebogen gebildeter Schlafqualitätsindex wurde ebenfalls als Prädiktor untersucht. Personenmerkmale (Geschlecht, Alter etc.) wurden adjustiert. Ergebnisse Die schlafbezogenen Fragebogenitems sagten die Tagebuchangaben signifikant vorher (p < 0,001). Der Schlafqualitätsindex (10,43 ± 6,16 Punkte) zeigte sich darüber hinaus als zusätzlicher Prädiktor für das Gefühl des Erholtseins, die Tagesschläfrigkeit und Konzentrationsfähigkeit (alle p < 0,05), nicht aber für die Einschlaflatenz (p > 0,05). Schlussfolgerung Ein laboreigener Diagnostikfragebogen ist eine valide Methode zur Erfassung von Schlafgewohnheiten und der Beschwerdesymptomatik bei Patienten mit schlafbezogener Atmungsstörung. Der Schlafqualitätsindex vermittelt Informationen über den subjektiven Tageszustand eines Patienten, was ihn als wertvolles Werkzeug des diagnostischen Prozesses auszeichnet.

Tracheal sound analysis for detection of sleep disordered breathing Abstract Objective This study aimed to investigate whether the combination of tracheal sounds and nasal pressure sensor (TS-NP) allows the same detection of apneas and hypopneas as the recommended American Academy of Sleep Medicine (AASM) method for obstructive sleep apnea (OSA) diagnosis, i.e., the combination of an oronasal thermistor and nasal pressure sensor (Therm-NP). Materials and methods Polysomnographic recordings of 33 patients (6 females; mean age 52.9 ± 10.3 years; mean body mass index, BMI, 30.0 ± 5.2 kg/m2) were analyzed to compare detection of apneas by two different methods of combined airflow signals: a) Therm-NP and b) TS-NP. The two scoring methods were performed randomly and independently of each other. Respiratory event detection results and apnea–hypopnea index (AHI) obtained using Therm-NP signals as a reference were compared to those obtained by TS-NP signals. Results The number of respiratory events scored using Therm-NP was 7268, while it was 7329 with TS-NP. The sensitivity and positive predictive value of TS-NP with respect to Therm-NP were 93.0 and 90.6, respectively. The average AHI for all patients was 29.8 ± 22.9 for Therm-NP and 30.0 ± 22.6/h for TS-NP. With the Therm-NP as a reference detection, a kappa statistic value of 0.86 for TS-NP revealed a high agreement for classifying OSA into the severity classes mild, moderate, and severe. However, 55% of total events scored by Therm-NP were hypopneas while 59% of events scored by TS-NP were apneas. Conclusion These results show that TS-NP reliably detects the same number of respiratory events as Therm-NP, despite a difference in the apnea to hypopnea ratio between the two methods. The use of TS does not modify AHI calculations and guarantees accurate sleep apnea diagnosis and severity assessment. Thus, TS can be used as a substitute for an oronasal thermistor in sleep recording systems.

Mitteilungen der DGSM

Dream recall frequency, nightmare frequency, attitude towards dreams, and other dream variables in patients with sleep-related breathing disorders Abstract Background and objectives Sleep and dreaming are inseparable. Therefore, this study addressed the question of whether the presence of specific sleep disorders affects dreaming. Materials and methods The present study included 1467 patients with sleep-related breathing disorders who completed a dream questionnaire. Results Dream life in these patients differed from control samples, most notably in heightened dream recall frequency, nightmare frequency, and frequency of sharing dreams. On the other hand, the positive attitude towards dreams and nightmare distress were rated lower by the patient group. Conclusion The findings indicate that sleep physiology, e. g., arousals terminating sleep apneas, might affect the dreaming process. In addition, future studies should also take into account the daytime distress associated with having a severe sleep disorder, as distress might have an effect on dream content and nightmare frequency.

Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182

6948891480

alsfakia@gmail.com