Project description:For the last 40 years, actigraphy or wearable accelerometry has provided an objective, low-burden and ecologically valid approach to assess real-world sleep and circadian patterns, contributing valuable data to epidemiological and clinical insights on sleep and sleep disorders. The proper use of wearable technology in sleep research requires validated algorithms that can derive sleep outcomes from the sensor data. Since the publication of the first automated scoring algorithm by Webster in 1982, a variety of sleep algorithms have been developed and contributed to sleep research, including many recent ones that leverage machine learning and / or deep learning approaches. However, it remains unclear how these algorithms compare to each other on the same data set and if these modern data science approaches improve the analytical validity of sleep outcomes based on wrist-worn acceleration data. This work provides a systematic evaluation across 8 state-of-the-art sleep algorithms on a common sleep data set with polysomnography (PSG) as ground truth. Despite the inclusion of recently published complex algorithms, simple regression-based and heuristic algorithms demonstrated slightly superior performance in sleep-wake classification and sleep outcome estimation. The performance of complex machine learning and deep learning models seem to suffer from poor generalization. This independent and systematic analytical validation of sleep algorithms provides key evidence on the use of wearable digital health technologies for sleep research and care.
Project description:BackgroundSpurred by the Coronavirus infectious disease 2019 pandemic, aerosol containment devices (ACDs) were developed to capture infectious respiratory aerosols generated by patients at their source. Prior reviews indicated that such devices had low evidence of effectiveness, but did not address how ACDs should be evaluated, how well they should perform, nor have clearly defined performance standards. Towards developing design criteria for ACDs, two questions were posed: 1) What characteristics have guided the design of ACDs? 2) How have these characteristics been evaluated?MethodsA scoping review was performed consistent with PRISMA guidelines. Data were extracted with respect to general study information, intended use of the device, device design characteristics and evaluation.ResultsFifty-four articles were included. Evaluation was most commonly performed with respect to device aerosol containment (n = 31, 61%), with only 5 (9%), 3 (6%) and 8 (15%) formally assessing providing experience, patient experience and procedure impact, respectively. Nearly all of the studies that explored provider experience and procedure impact studied intubation. Few studies provided a priori performance criteria for any evaluation metric, or referenced any external guidelines by which to bench mark performance.ConclusionWith respect to aerosol containment, ACDs should reduce exposure among HCP with the device compared with the absence of the device, and provide ≥90% reduction in respirable aerosols, equivalent in performance to N95 filtering facepiece respirators, if the goal is to reduce reliance on personal protective equipment. The ACD should not increase awkward or uncomfortable postures, or adversely impact biomechanics of the procedure itself as this could have implications for procedure outcomes. A variety of standardized instruments exist to assess the experience of patients and healthcare personnel. Integration of ACDs into routine clinical practice requires rigorous studies of aerosol containment and the user experience.
Project description:The objective was to investigate the persistence of sleep difficulties for over 16 years amongst a population of working age. In this prospective cohort study, a group-based trajectory analysis of repeated surveys amongst 66,948 employees in public sector (mean age 44.7 [SD 9.4] years, 80% women) was employed. The main outcome measure was sleep difficulties based on Jenkins Sleep Scale (JSS). Up to 70% of the respondents did not experience sleep difficulties whereas up to 4% reported high frequency of notable sleep difficulties through the entire 16-year follow-up. Heavy drinking predicted sleep difficulties (OR 2.3 95% CI 1.6 to 3.3) except for the respondents younger than 40 years. Smoking was associated with sleep difficulties amongst women younger than 40 years (OR 1.2, 95% CI 1.0 to 1.5). Obesity was associated with sleep difficulties amongst men (OR 1.9, 95% CI 1.4 to 2.7) and women (OR 1.2, 95% CI 1.1 to 1.3) of middle age and amongst women older than 50 (OR 1.5, 95% CI 1.2 to 1.8) years. Physical inactivity predicted sleep difficulties amongst older men (OR 1.3, 95% CI 1.1 to 1.6). In this working-age population, sleep difficulties showed a great persistence over time. In most of the groups, the level of sleep difficulties during the follow-up was almost solely dependent on the level of initial severity. Depending on sex and age, increasing sleep problems were sometimes associated with high alcohol consumption, smoking, obesity and physical inactivity, but the strength of these associations varied.
Project description:Study of emerging sleep-wake patterns in neonates is important for promptly identifying and treating abnormal sleep behaviours to ensure healthy infant development and neurobehavioral outcomes. Current methods to assess sleep are costly, labour intensive, and particularly difficult to implement in fragile, hospitalised infants requiring intensive medical care. The aim of the present study was to assess the validity of actigraphy as a tool for detecting sleep in preterm infants, using polysomnography (PSG) as the "gold standard". A total of 10 neonates (mean [SD] 35.8 [1.2] weeks post-menstrual age; five female) hospitalised since birth for prematurity each participated in one 8-10 hr session during which PSG and actigraphy were recorded simultaneously. Inter-feed minute-by-minute PSG Sleep-Wake scores were compared to concurrent actigraph epochs categorised as either "Sleep" or "Wake" using three separate movement-per-minute thresholds (≤20, ≤40, ≤80). Tool validity was assessed using five metrics. A key finding was that for each of the movement thresholds there was high agreement rate, sensitivity, and predictive value of sleep (85.2%-97.2%), whereas specificity and predictive value of wake remained low (12%-46%). Receiver operating characteristic curve analysis also revealed low discriminatory power of actigraphy for estimating sleep (area under the curve = 0.636; Youden's Index J = 0.2173). Lack of sufficient minutes of autonomous wake periods among infants was identified as a key limitation in actigraphy. Findings from the present study suggest actigraphy cannot be validated for Sleep/Wake discrimination in preterm infants and that proper validation requires sufficient data from periods of both Sleep and Wake.
Project description:Actigraphic (ACT) recordings are used widely in schoolchildren as a less intrusive and more extended approach to evaluation of sleep problems. However, critical assessment of the validity and reliability of ACT against overnight polysomnography (NPSG) are unavailable. Thus, we explored the degree of concordance between NPSG and ACT in school-aged children to delineate potential ACT boundaries when interpreting pediatric sleep. Non-dominant wrist ACT was recorded simultaneously with NPSG in 149 healthy school-aged children (aged 4.1-8.8 years, 41.7% boys, 80.4% Caucasian) recruited from the community. Analyses were limited to the Actiware (MiniMitter-64) calculated parameters originating from 1-min epoch sampling and medium sensitivity threshold value of 40; i.e. sleep period time (SPT), total sleep time (TST) and wake after sleep onset (WASO). SPT was not significantly different between ACT and NPSG. However, ACT underestimated TST significantly by 32.2±33.4 min and overestimated WASO by 26.3±34.4 min. The decreased precision of ACT was also evident from moderate to small concordance correlation coefficients (0.47 for TST and 0.09 for WASO). ACT in school-aged children provides reliable assessment of sleep quantity, but is relatively inaccurate during determination of sleep quality. Thus, caution is advocated in drawing definitive conclusions from ACT during evaluation of the sleep-disturbed child.
Project description:Study objectivesTo compare the quality and consistency in sleep measurement of a consumer wearable device and a research-grade actigraph with polysomnography (PSG) in adolescents.MethodsFifty-eight healthy adolescents (aged 15-19 years; 30 males) underwent overnight PSG while wearing both a Fitbit Alta HR and a Philips Respironics Actiwatch 2 (AW2) for 5 nights, with either 5 hours or 6.5 hours time in bed (TIB) and for 4 nights with 9 hours TIB. AW2 data were evaluated using two different wake and immobility thresholds. Discrepancies in estimated total sleep time (TST) and wake after sleep onset (WASO) between devices and PSG, as well as epoch-by-epoch agreements in sleep/wake classification, were assessed. Fitbit-generated sleep staging was compared to PSG.ResultsFitbit and AW2 under default settings similarly underestimated TST and overestimated WASO (TST: medium setting (M10) ≤ 38 minutes, Fitbit ≤ 47 minutes; WASO: M10 ≤ 38 minutes; Fitbit ≤ 42 minutes). AW2 at the high motion threshold setting provided readings closest to PSG (TST: ≤ 12 minutes; WASO: ≤ 18 minutes). Sensitivity for detecting sleep was ≥ 90% for both wearable devices and further improved to 95% by using the high threshold (H5) setting for the AW2 (0.95). Wake detection specificity was highest in Fitbit (≥ 0.88), followed by the AW2 at M10 (≥ 0.80) and H5 thresholds (≤ 0.73). In addition, Fitbit inconsistently estimated stage N1 + N2 sleep depending on TIB, underestimated stage N3 sleep (21-46 min), but was comparable to PSG for rapid eye movement sleep. Fitbit sensitivity values for the detection of N1 + N2, N3 and rapid eye movement sleep were ≥ 0.68, ≥ 0.50, and ≥ 0.72, respectively.ConclusionsA consumer-grade wearable device can measure sleep duration as well as a research actigraph. However, sleep staging would benefit from further refinement before these methods can be reliably used for adolescents.Clinical trial registrationRegistry: ClinicalTrials.gov; Title: The Cognitive and Metabolic Effects of Sleep Restriction in Adolescents; Identifier: NCT03333512; URL: https://clinicaltrials.gov/ct2/show/NCT03333512.CitationLee XK, Chee NIYN, Ong JL, Teo TB, van Rijn E, Lo JC, Chee MWL. Validation of a consumer sleep wearable device with actigraphy and polysomnography in adolescents across sleep opportunity manipulations. J Clin Sleep Med. 2019;15(9):1337-1346.
Project description:Study objectivesLimited data exist on the association between trauma and sleep across developmental stages, particularly trauma experienced in childhood and sleep in adulthood. We assessed sleep quality across the developmental spectrum among avalanche survivors 16 years after exposure as compared to a matched comparison cohort.MethodsParticipants were survivors of two avalanche-affected towns (n = 286) and inhabitants of non-exposed towns (n = 357). Symptoms were assessed with respect to the survivors' developmental stage at the time of the disaster: childhood (2-12), adolescence (13-19), young adult (20-39), and adult (≥ 40). The Posttraumatic Diagnostic Scale, Pittsburgh Sleep Quality Index and Pittsburgh Sleep Quality Index PTSD Addendum were used.ResultsOverall PTSD symptoms were not associated with avalanche exposure in any age groups under study. However, survivors who were children at the time of the disaster were 2.58 times (95% CI 1.33-5.01) more likely to have PTSD-related sleep disturbances (PSQI-A score ≥ 4) in adulthood than their non-exposed peers, especially symptoms of acting out dreams (aRR = 3.54; 95% CI 1.15-10.87). Those who were adults at time of the exposure had increased risk of trauma-related nightmares (aRR = 2.69; 95% CI 1.07-6.79 for young adults aRR = 3.07; 95% CI 1.51-6.24 for adults) compared to their non-exposed peers.ConclusionsOur data indicate a chronicity of PTSD-related sleep disturbances, particularly among childhood trauma survivors. REM sleep disturbances may have different manifestations depending on the developmental stage at the time of trauma exposure.
Project description:BackgroundKnowledge about the occurrence and distribution of musculoskeletal problems in early life is needed. The objectives were to group children aged 8 to 16 according to their distribution of pain in the spine, lower- and upper extremity, determine the proportion of children in each subgroup, and describe these in relation to sex, age, number- and length of episodes with pain.MethodData on musculoskeletal pain from about 1,000 Danish schoolchildren was collected over 3 school years (2011 to 2014) using weekly mobile phone text message responses from parents, indicating whether their child had pain in the spine, lower extremity and/or upper extremity. Result are presented for each school year individually.ResultsWhen pain was defined as at least 1 week with pain during a school year, Danish schoolchildren could be divided into three almost equally large groups for all three school years: Around 30% reporting no pain, around 40% reporting pain in one region, and around 30% reporting pain in two or three regions. Most commonly children experienced pain from the lower extremities (~ 60%), followed by the spine (~ 30%) and the upper extremities (~ 23%). Twice as many girls reported pain in all three sites compared to boys (10% vs. 5%) with no other statistically significant sex or age differences observed. When pain was defined as at least 3 weeks with pain during a schoolyear, 40% reported pain with similar patterns to those for the more lenient pain definition of 1 week.ConclusionDanish schoolchildren often experienced pain at more than one pain site during a schoolyear, and a significantly larger proportion of girls than boys reported pain in all three regions. This could indicate that, at least in some instances, the musculoskeletal system should be regarded as one entity, both for clinical and research purposes.
Project description:Actigraphy, a method for inferring sleep/wake patterns based on movement data gathered using actigraphs, is increasingly used in population-based epidemiologic studies because of its ability to monitor activity in natural settings. Using special software, actigraphic data are analyzed to estimate a range of sleep parameters. To date, despite extensive application of actigraphs in sleep research, published literature specifically detailing the methodology for derivation of sleep parameters is lacking; such information is critical for the appropriate analysis and interpretation of actigraphy data. Reporting of sleep parameters has also been inconsistent across studies, likely reflecting the lack of consensus regarding the definition of sleep onset and offset. In addition, actigraphy data are generally underutilized, with only a fraction of the sleep parameters generated through actigraphy routinely used in current sleep research. The objectives of this paper are to review existing algorithms used to estimate sleep/wake cycles from movement data, demonstrate the rules/methods used for estimating sleep parameters, provide clear technical definitions of the parameters, and suggest potential new measures that reflect intraindividual variability. Utilizing original data collected using Motionlogger Sleep Watch (Ambulatory Monitoring Inc., Ardsley, NY), we detail the methodology and derivation of 29 nocturnal sleep parameters, including those both widely and rarely utilized in research. By improving understanding of the actigraphy process, the information provided in this paper may help: ensure appropriate use and interpretation of sleep parameters in future studies; enable the recalibration of sleep parameters to address specific goals; inform the development of new measures; and increase the breadth of sleep parameters used.
Project description:BackgroundIn many large hospitals in Switzerland, adolescents 16 years and older are treated in adult emergency departments (ED). There have been few publications about this specific patient population, especially in Switzerland. This study aims to provide an overview of emergency presentations of adolescents between 16-18 years of age when compared to adults and focuses on their principle complaints.MethodsWe conducted a single-centre, retrospective, cross-sectional study of all patients aged 16 years and older presenting to the adult ED at the University Hospital (Inselspital) in Bern, Switzerland, from 2013 to 2017. This analysis gives an overview of emergency presentations of adolescents between 16-18 years of age in this time period and compares their consultation characteristics to those of adult patients.ResultsData of a total of 203,817 patients who presented to our adult ED between 2013 and 2017 were analysed. Adolescents account for 2.5% of all emergency presentations. The number of ED presentations in the reviewed time period rose for adults (+2368, 95% CI: 1695, 3041, p = 0.002 consultations more per year; +25% comparing 2013 with 2017), while adolescent presentations did not significantly increase (p = 0.420). In comparison to adult patients, adolescents presented significantly more often during the night (39.1% vs. 31.5%, p < 0.001), as walk-ins (54.2% vs. 44.9%, p < 0.001), or with less highly acute complaints at triage (21% vs. 31%, p < 0.001). They were more likely to be discharged (70.8% vs. 52.2%, p < 0.001). We found a significant association between the two age groups and principle complaints. In comparison to adults, trauma and psychiatric problems were significantly more common among adolescents.ConclusionsOur data showed that complaints in adolescent patients under 18 years of age significantly differ from those in older patients. The artificial age cut-off therefore puts this vulnerable population at risk of receiving inadequate diagnostic testing and treatment adapted only for adults. Additional studies are needed on the reasons adolescents and young adults seek ED care, as this could lead to improvements in the care processes for this vulnerable population.