Project description:In human sleep studies, the probability of discomfort from the electrodes and the change in environment usually results in first-night recordings being discarded. Sleep recordings from the first night in human subjects often differ in amount of REM (rapid eye movement) sleep and the overall sleep architecture. This study investigated whether recordings of sleep states in dairy cows also show a first-night effect. Non-invasive electrophysiological recordings were carried out on nine cows of the Swedish Red breed during three consecutive 24-hour periods (recording days 1-3). Overall, cows spent 12.9 ± 1.4 hours awake, 8.2 ± 1 hours ruminating, 57.2 ± 20.3 min drowsing, 44.1 ± 20.2 min in REM sleep and 64.3 ± 38.1 min in NREM (non-rapid eye movement) sleep (mean ± SD) and there were no significant differences between recording days in total duration for any of the sleep and awake states. However, the bouts of REM sleep and rumination were longer, and the awake bouts were shorter, at night time compared to daytime, regardless of recording day. The awake bouts also showed an interaction effect with longer bouts at daytime during day 1 compared to daytime on day 3. Data on sleep and awake states recorded in adult dairy cows during three consecutive 24-h periods showed great variation in sleep time between cows, but total time for each state was not significantly affected by recording day. Further and more detailed studies of how sleep architecture is affected by recording day is necessary to fully comprehend the first-night effect in dairy cows.
Project description:RationaleHome sleep apnea testing (HSAT) typically does not include electroencephalogram (EEG) monitoring for sleep assessment. In patients with insomnia and low sleep efficiency, overestimation of the sleep period can result from absence of EEG, which will reduce sleep disordered breathing (SDB) indices and may lead to a false-negative result.ObjectiveTo validate a single channel frontal EEG for scoring sleep versus wake against full EEG during polysomnography, and then to examine the utility of adding this single channel EEG to standard HSAT to prevent false-negative results.MethodsEpoch-by-epoch validation for sleep scoring of single channel EEG versus full PSG was first performed in 21 subjects. This was followed by a separate retrospective analysis of 207 consecutive HSATs in adults performed in a university-affiliated sleep center using the Somte (Compumedics) HSAT with one frontal EEG as well as chin EMG, nasal airflow, oxyhemoglobin saturation, respiratory effort, pulse rate, and body position. Each study was scored twice, with (HSATEEG) and without the EEG signal visible (HSATPolygraphy), to calculate AHI4 and RDI and the effect on OSA diagnosis and severity. Analyses were repeated in 69 patients with poor sleep suggesting insomnia plus Epworth Sleepiness Scale < 7 as well as in 38 patients ultimately shown to have sleep efficiency < 70% on HSAT with EEG.Measurements and main resultsSingle channel and full EEG during polysomnography agreed on sleep versus wake in 92-95% of all epochs. HSAT without EEG overestimated the sleep period by 20% (VST = 440 ± 76 min vs TST = 356 ± 82 min), had a false-negative rate of 8% by AHI4 criteria, and underestimated disease severity in 11% of all patients. Sub-group analysis of patients with subjective poor sleep suggesting insomnia did not change the results. Patients later shown to have low sleep efficiency had lower SDB indices and a 20.8% false negative rate of sleep apnea diagnosis.ConclusionsAlthough overall false negative rates using HSATPolygraphy were moderate, suggesting utility for ruling out OSA, there was a specific subgroup in whom there were significant missed diagnoses. However, we were unable to identify this subgroup a priori.
Project description:People with Insomnia Disorder tend to underestimate their sleep compared with polysomnography or actigraphy, a phenomenon known as paradoxical insomnia or sleep-state misperception. Previous studies suggested that night-to-night variability could be an important feature differentiating subtypes of misperception. This study aimed for a data-driven definition of misperception subtypes revealed by multiple sleep features including night-to-night variability. We assessed features describing the mean and dispersion of misperception and objective and subjective sleep duration from 7-night diary and actigraphy recordings of 181 people with Insomnia Disorder and 55 people without sleep complaints. A minimally collinear subset of features was submitted to latent class analysis for data-driven subtyping. Analysis revealed three subtypes, best discriminated by three of five selected features: an individual's shortest reported subjective sleep duration; and the mean and standard deviation of misperception. These features were on average 5.4, -0.0 and 0.5 hr in one subtype accommodating the majority of good sleepers; 4.1, -1.4 and 1.0 hr in a second subtype representing the majority of people with Insomnia Disorder; and 1.7, -2.2 and 1.5 hr in a third subtype representing a quarter of people with Insomnia Disorder and hardly any good sleepers. Subtypes did not differ on an individual's objective sleep duration mean (6.9, 7.2 and 6.9 hr) and standard deviation (0.8, 0.8 and 0.9 hr). Data-driven analysis of naturalistic sleep revealed three subtypes that markedly differed in misperception features. Future studies may include misperception subtype to investigate whether it contributes to the unexplained considerable individual variability in treatment response.
Project description:Study objectivesTo evaluate home sleep apnea testing (HSAT) using a type 3 portable monitor to help diagnose sleep-disordered breathing (SDB) and identify respiratory events including obstructive sleep apnea, central sleep apnea, and Cheyne-Stokes respiration in adults with stable chronic heart failure.MethodsEighty-four adults with chronic heart failure (86.9% males, age [mean ± standard deviation] 58.7 ± 16.3 years, body mass index 29.4 ± 13.0 kg/m², left ventricular ejection fraction 40.3% ± 11.5%) performed unattended HSAT followed by an in-laboratory polysomnography (PSG) with simultaneous portable monitor recording.ResultsThe apnea-hypopnea index was 22.0 ± 17.0 events/h according to HSAT, 26.8 ± 20.5 events/h on an in-laboratory portable monitor, and 23.8 ± 21.3 events/h using PSG (P = .373). A Bland-Altman analysis of the apnea-hypopnea index using HSAT vs PSG showed a mean difference (95% confidence interval) of -2.4 (-4.9 to 0.1) events/h and limits of agreement (±2 standard deviations) of -24.1 to 19.2 events/h. HSAT underestimated the apnea-hypopnea index to a greater extent at a higher apnea-hypopnea index (rho = -.358; P < .001). Similar levels of agreement from HSAT vs PSG were observed when comparing the obstructive apnea index, central apnea index, and percentage of time in a Cheyne-Stokes respiration pattern. When we used an apnea-hypopnea index ≥ 5 events/h to diagnose SDB, HSAT had 86.7% sensitivity, 76.5% specificity, 92.9% positive predictive value, and 61.9% negative predictive value compared to PSG. Detection of Cheyne-Stokes respiration using HSAT showed 94.6% sensitivity, 91.1% specificity, 88.6% positive predictive value, and 97.6% negative predictive value compared to PSG.ConclusionsHSAT with a type 3 portable monitor can help diagnose SDB and identify obstructive sleep apnea, central sleep apnea, and Cheyne-Stokes respiration events in adults with chronic heart failure.
Project description:Study objectivesCompare auto-adjusting positive airway pressure (APAP) treatment with positive airway pressure (PAP) titration by polysomnography (PSG) followed by CPAP treatment in patients diagnosed with obstructive sleep apnea (OSA) by home sleep apnea testing (HSAT).DesignProspective randomized treatment study.SettingTertiary Veterans Administration Medical Center.Participants156 patients diagnosed with OSA by HSAT (apneahypopnea index [AHI] ≥ 10/h) suitable for APAP treatment.InterventionsAPAP arm: Treatment with an APAP device, CPAP arm: PSG PAP titration followed by CPAP treatment.MeasurementsMean PAP adherence, Epworth sleepiness scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ).ResultsThe mean (± SD) age, BMI, and diagnostic AHI (APAP: 28.6 ± 18.5, CPAP: 28.3 ± 16.0/h, p = NS) did not differ between the study arms. After 6 weeks of treatment, 84.6% of 78 patients started on APAP and 84.3% of 70 patients started on CPAP (8 declined treatment after the titration) were using PAP, p = NS. The 90% APAP and level of CPAP were similar (10.8 ± 3.1, 11.7 ± 2.5 cm H2O, p = 0.07). The average nightly PAP use did not differ (APAP: 4.45 ± 2.3, CPAP: 4.0 ± 2.3 h, p = NS). The improvements in the ESS (APAP: -4.2 ± 4.7, CPAP: -3.7 ± 4.8, p = NS) and in the FOSQ (APAP: 2.6 ± 3.5, CPAP: 2.2 ± 3.7, p = NS) were not different.ConclusionsFollowing diagnosis of OSA by HSAT, treatment with APAP results in equivalent PAP adherence and improvement in sleepiness compared to a PSG titration and CPAP treatment.CommentaryA commentary on this article appears in this issue on page 1277.
Project description:PurposeTo determine the agreement between the manual scoring of home sleep apnea tests (HSATs) by international sleep technologists and automated scoring systems.MethodsFifteen HSATs, previously recorded using a type 3 monitor, were saved in European Data Format. The studies were scored by nine experienced technologists from the sleep centers of the Sleep Apnea Global Interdisciplinary Consortium (SAGIC) using the locally available software. Each study was scored separately by human scorers using the nasal pressure (NP), flow derived from the NP signal (transformed NP), or respiratory inductive plethysmography (RIP) flow. The same procedure was followed using two automated scoring systems: Remlogic (RLG) and Noxturnal (NOX).ResultsThe intra-class correlation coefficients (ICCs) of the apnea-hypopnea index (AHI) scoring using the NP, transformed NP, and RIP flow were 0.96 [95% CI 0.93-0.99], 0.98 [0.96-0.99], and 0.97 [0.95-0.99], respectively. Using the NP signal, the mean differences in AHI between the average of the manual scoring and the automated systems were - 0.9 ± 3.1/h (AHIRLG vs AHIMANUAL) and - 1.3 ± 2.6/h (AHINOX vs AHIMANUAL). Using the transformed NP, the mean differences in AHI were - 1.9 ± 3.3/h (AHIRLG vs AHIMANUAL) and 1.6 ± 3.0/h (AHINOX vs AHIMANUAL). Using the RIP flow, the mean differences in AHI were - 2.7 ± 4.5/h (AHIRLG vs AHIMANUAL) and 2.3 ± 3.4/h (AHINOX vs AHIMANUAL).ConclusionsThere is very strong agreement in the scoring of the AHI for HSATs between the automated systems and experienced international technologists. Automated scoring of HSATs using commercially available software may be useful to standardize scoring in future endeavors involving international sleep centers.
Project description:INTRODUCTION: Electronic devices in the bedroom are broadly linked with poor sleep in adolescents. This study investigated whether there is a dose-response relationship between use of electronic devices (computers, cellphones, televisions and radios) in bed prior to sleep and adolescent sleep patterns. METHODS: Adolescents aged 11-17 yrs (n?=?1,184; 67.6% female) completed an Australia-wide internet survey that examined sleep patterns, sleepiness, sleep disorders, the presence of electronic devices in the bedroom and frequency of use in bed at night. RESULTS: Over 70% of adolescents reported 2 or more electronic devices in their bedroom at night. Use of devices in bed a few nights per week or more was 46.8% cellphone, 38.5% computer, 23.2% TV, and 15.8% radio. Device use had dose-dependent associations with later sleep onset on weekdays (highest-dose computer adjOR ?=?3.75: 99% CI ?=?2.17-6.46; cellphone 2.29: 1.22-4.30) and weekends (computer 3.68: 2.14-6.32; cellphone 3.24: 1.70-6.19; TV 2.32: 1.30-4.14), and later waking on weekdays (computer 2.08: 1.25-3.44; TV 2.31: 1.33-4.02) and weekends (computer 1.99: 1.21-3.26; cellphone 2.33: 1.33-4.08; TV 2.04: 1.18-3.55). Only 'almost every night' computer use (: 2.43: 1.45-4.08) was associated with short weekday sleep duration, and only 'almost every night' cellphone use (2.23: 1.26-3.94) was associated with wake lag (waking later on weekends). CONCLUSIONS: Use of computers, cell-phones and televisions at higher doses was associated with delayed sleep/wake schedules and wake lag, potentially impairing health and educational outcomes.
Project description:BackgroundFor optimal fertility testing, serum anti-Müllerian hormone levels are used in combination with other testing to provide reliable ovarian reserve evaluations. The use of the ADx 100 card is widely commercially available for at-home reproductive hormone testing, but data demonstrating that its results are reproducible outside of a clinical setting are limited, as well as comparisons of its performance with other newer blood collection techniques. This study aimed to evaluate the concordance of serum AMH levels found via standard venipuncture and self-administered blood collection using the TAP II device (TAP) and ADx card in women of reproductive age.MethodsThis was a prospective, head-to-head-to-head within-person crossover comparison trial that included 41 women of reproductive age (20-39 years). It was hypothesized that the TAP device would be superior to the ADx card both in terms of agreement with venipuncture reference standard and patient experience. Each subject had their blood drawn using the three modalities (TAP, ADx, and venipuncture). We evaluated the concordance of AMH assays from samples obtained via the TAP device and ADx card with the gold standard being venipuncture. Two-sided 95% CIs were generated for each method to compare relative performance across all three modes. Patient preference for the TAP device versus the ADx card was based on self-reported pain and Net Promoter Score (NPS).ResultsThe TAP device was superior to the ADx card on all outcome measures. TAP R-squared with venipuncture was 0.99 (95% CI 0.99, > 0.99), significantly higher than the ADx card, which had an R-squared of 0.87 (95% CI 0.80, 0.94) under most favorable treatment. TAP sensitivity and specificity were both 100% (no clinical disagreement with venipuncture), versus 100 and 88%, respectively, for the ADx card. Average pain reported by users of the TAP device was significantly lower than the ADx card (0.75 versus 2.73, p < 0.01) and the NPS was significantly higher than the ADx card (+ 72 versus - 48, p < 0.01).ConclusionsThe TAP was non-inferior to venipuncture and superior to the ADx card with respect to correlation and false positives. Moreover, the TAP was superior to both alternatives on patient experience.Trial registrationNCT04784325 (Mar 5, 2021).
Project description:Study objectivesHome sleep testing (HST) is used worldwide to confirm the presence of obstructive sleep apnea (OSA). We sought to determine the agreement of HST scoring among international sleep centers.MethodsFifteen HSTs, previously recorded using a type 3 monitor, were deidentified and saved in European Data Format. The studies were scored by nine technologists from the sleep centers of the Sleep Apnea Global Interdisciplinary Consortium (SAGIC) using the locally available software. Each study was scored separately using one of three different airflow signals: nasal pressure (NP), transformed (square root) nasal pressure signal (transformed NP), and uncalibrated respiratory inductive plethysmography (RIP) flow. Only one of the three airflow signals was visible to the scorer at each scoring session. The scoring procedure was repeated to determine the intrarater reliability.ResultsThe intraclass correlation coefficients (ICCs) using the NP were: apnea-hypopnea index (AHI) = 0.96 (95% confidence interval [CI]: 0.93-0.99); apnea index = 0.91 (0.83-0.96); and hypopnea index = 0.75 (0.59-0.89). The ICCs using the transformed NP were: AHI = 0.98 (0.96-0.99); apnea index = 0.95 (0.90-0.98); and hypopnea index = 0.90 (0.82-0.96). The ICCs using the RIP flow were: AH I = 0.98 (0.96-0.99); apnea index = 0.66 (0.48-0.84); and hypopnea index = 0.78 (0.63-0.90). The mean difference of first and second scoring sessions of the same respiratory variables ranged from -1.02 to 0.75/h.ConclusionThere is a strong agreement in the scoring of the respiratory events for HST among international sleep centers. Our results suggest that centralized scoring of HSTs may not be necessary in future research collaboration among international sites.CommentaryA commentary on this article appears in this issue on page 7.