Reliability of commercially available sleep and activity trackers with manual switch-to-sleep mode activation in free-living healthy individuals.

INTRODUCTION: Wearable health devices have become trendy among consumers, but it is not known whether they accurately measure sleep and physical activity parameters. To address this question, we have studied the measured data of two consumer-level activity monitors (Up Move Jawbone® (U) and Withings Pulse 02® (W)) and compared it with reference methods for sleep and activity recordings, namely the Bodymedia SenseWear Pro Armband® actigraph (SWA) and home-polysomnography (H-PSG). METHODS: Twenty healthy patients were assessed at home, during sleep, with the four devices. An additional 24-h period of recording was then planned during which they wore the 2 trackers and the SWA. Physical activity and sleep parameters obtained with the 4 devices were analyzed. RESULTS: Significant correlations with H-PSG were obtained for total sleep time (TST) for all the devices: r=0.48 for W (p=0.04), r=0.63 for U (p=0.002), r=0.7 for SWA (p=0.0003). The best coefficient was obtained with SWA. Significant correlations were also obtained for time in bed (TIB) for U and SWA vs PSG (r=0.79 and r=0.76, p<0.0001 for both) but not for W (r=0.45, p=0.07). No significant correlations were obtained for deep sleep, light sleep, and sleep efficiency (SE) measurements with W, U and SWA. Sleep latency (SL) correlated with H-PSG only when measured against SWA (r=0.5, p=0.02). Physical activity assessment revealed significant correlations for U and W with SWA for step count (both r=0.95 and p<0.0001) and active energy expenditure (EE) (r=0.65 and 0.54; p=0.0006 and p<0.0001). Total EE was also correctly estimated (r=0.75 and 0.52; p<0.0001 and p=0.001). CONCLUSION: Sleep and activity monitors are only able to produce a limited set of reliable measurements, such as TST, step count, and active EE, with a preference for U which performs globally better. Despite the manual activation to sleep mode, U and W were not suitable for giving correct data such as sleep architecture, SE, and SL. In the future, to enhance accuracy of such monitors, researchers and providers have to collaborate to write algorithms based reliably on sleep physiology. It could avoid misleading the consumer.

Improvement of sleep architecture parameters in cirrhotic patients with recurrent hepatic encephalopathy with the use of rifaximin.

BACKGROUND AND AIM: Sleep disorders are frequently reported in patients with cirrhosis and hepatic encephalopathy (HE). This study assessed the effect of rifaximin on sleep architecture parameters in patients with recurrent HE. PATIENTS AND METHODS: This sequential, prospective, and exploratory study involved all patients with cirrhosis and recurrent HE admitted between June 2014 and September 2015. HE was assessed according to the West-Haven Classification. Patients underwent 24-h polysomnography (PSG) and 7-day actigraphy. Rapid eye movement (REM) sleep was considered to be an indicator of good sleep quality. Patients completed questionnaires assessing the quality of sleep and sleepiness. After a 28-day course of rifaximin, the same assessment was repeated. RESULTS: Fifteen patients were included (nine men, mean age: 57±11 years). Child-Pugh scores ranged from B7 to C15. Before rifaximin, the mean HE score was 2.7±0.7. Data from PSG analysis indicated long total sleep time (TST): 571±288 min, and limited REM sleep: 2.5% TST (0-19). Seven-day actigraphy showed an impaired number of steps: 1690/24 h (176-6945). Questionnaires indicated that patients experienced impaired sleep quality and excessive daytime sleepiness. After rifaximin, HE scores decreased to 1.7±0.6 (P<0.001). REM sleep increased to 8.5% TST (0-25) (P=0.003). No changes were observed for TST, number of steps, and on questionnaires. CONCLUSION: Patients with recurrent HE suffer from poor sleep quality and excessive daytime sleepiness. On 24-h PSG, rifaximin improves objective sleep architecture parameters with no changes in the subjective quality of sleep and sleepiness.

Comparison between home and hospital set-up for unattended home-based polysomnography: a prospective randomized study.

BACKGROUND: Unattended home-based polysomnography (H-PSG) is a reliable tool for the diagnosis of obstructive sleep apnoea (OSA). The quality of the recording can be influenced by several factors including the set-up location - at home versus in the sleep laboratory. Previous studies have suggested that the failure rate is higher when H-PSG is fitted in hospital. The aim of this study was to determine the influence of hook-up location on H-PSG recording quality. Feasibility and repeatability of H-PSG were also assessed. METHODS: Consecutive patients suspected of OSA were selected. Each patient underwent two H-PSGs within two weeks, one fitted at home and one fitted in the sleep laboratory. The order of H-PSG was randomly assigned. RESULTS: Among the 102 included patients, 95 completed the study. Ninety-three per cent of the 190 H-PSGs were satisfactory. The failure rate of H-PSG was similar for both the home set-up and the sleep laboratory set-up (p = 0.33). Seventy-nine per cent of patients opted to be fitted at home. OSA was diagnosed in 59%. The apnoea-hypopnoea index was similar for home and sleep laboratory set-up, resulting in a very good reproducibility (intraclass correlation coefficient of 0.85). No differences in total sleep time and sleep architecture were observed in both set-up protocols. Except for sleep duration, which was longer in the first H-PSG test, we did not observe any first-night effect during the first H-PSG. CONCLUSION: The present study demonstrates that hospital hook-up is as effective as home hook-up for home-unattended polysomnography, and that feasibility and repeatability of H-PSG are very good.

Real-time attended home-polysomnography with telematic data transmission.

PURPOSE: Home-polysomnography (HPSG) has been proposed as a cost-effective alternative for obstructive sleep apnea (OSA) diagnosis. We assessed, in a feasibility study, whether telematic transmission using the Dream® and Sleepbox® technologies was associated with low HPSG failure rate. METHODS: Patients referred by chest physicians for clinical suspicion of OSA underwent one HPSG, using Dream® and Sleepbox® (Medatec, Belgium), which is a wireless system able to communicate with Dream®, and with Internet through a wi-fi/3G interface. It is equipped with a digital infrared camera, and with a speaker/microphone system for bidirectional audio/video communication via Skype®. The Sleep Lab nurse performed a remote discontinuous monitoring of the PSG. In case of sensor loss, she called the patient who had been previously educated to replace the sensors. RESULTS: Twenty-one patients have been studied. 90% of the recordings were of excellent quality. We observed a 10% PSG failure rate: one failure of the Dream®, and one recording of poor quality. There were 2 successful Skype® interventions resulting in readjustment of the defective probes (nasal cannula and EEG). PSG signal visualization was possible in 90% of cases but Skype® connection was problematic in 19% of cases. However, patients could be reached by phone to solve the problem. CONCLUSIONS: Real-time attended HPSG through telematic data transmission is feasible and could be an interesting perspective to decrease the failure rate of home sleep studies, even if some technical aspects need to be improved.

Sleep efficiency during sleep studies: results of a prospective study comparing home-based and in-hospital polysomnography.

To date, the clinical use of unattended home-based polysomnography (PSG) is not recommended. To assess whether sleep efficiency is better at home, we have performed a prospective, crossover, single-blind study comparing unattended home- versus attended in-hospital PSG in a population referred for high clinical suspicion of obstructive sleep apnoea syndrome (OSA). Within 2 weeks, all the patients underwent both PSG performed by the same sleep technician, which were analysed by another blinded technician. Payments for each procedure were also calculated. Sixty-six patients (mean age: 49±13 years; mean body mass index: 30±7; mean Epworth Sleepiness Scale: 10±5) were included. The quality of recordings was poor in 1.5% of the attended PSG versus 4.7% for unattended PSG (P=0.36). Sleep efficiency at home was better (82% versus 75%, P<0.001), and sleep duration longer (412 min versus 365 min, P<0.001). Sleep latency was also shorter at home (28 min versus 45 min, P=0.004), and patients spent more time in rapid eye movement sleep (19% versus 16%, P=0.006). Apnoea-hypopnoea index (23 versus 26, P=0.08) was similar at home and in the sleep lab. Sixty-seven per cent of patients preferred home-based PSG. PSG payment was also lower at home (268 Euros versus 1057 Euros). We conclude that home-based PSG is associated with a better sleep efficiency. It also appears as feasible and reliable in patients with high preclinical suspicion for OSA. It is also more comfortable for the patients whose sleep efficiency is better and allows cost saving related to the absence of hospitalization.

Detection of bed-exit events using a new wireless bed monitoring assistance.

OBJECTIVES: To assess, using complete polysomnography as the gold standard, the capability of Heasys(®), an innovative wireless bed monitoring assistance to record body movements and presence and to infer bed-exit events and body position changes at night. DESIGN: Descriptive study. SETTINGS: Sleep laboratory for patient's recording and home for healthy volunteers. PARTICIPANTS: Twelve patients referred for suspicion or treatment of sleep disordered breathing and 5 healthy subjects. MEASUREMENTS: Complete polysomnography was recorded during one night in patients and during two nights in healthy volunteers. Heasys(®) sheet was placed under the fitted bed sheet to allow concomitant recording. During the second night, healthy subjects were asked to get out of bed at least 2 times for a minimal duration of 3 min. RESULTS: Heasys(®) allowed the detection of all bed-exit events in patients and volunteers (sensitivity: 100%, and specificity: 85%). When bed-exit events were defined by the lack of the presence signal combined with absence of motion and a dip in temperature, sensitivity and specificity of Heasys(®) were 92 and 100%, respectively. In patients and volunteers, Heasys(®) detected body position changes recorded by polysomnography respectively, in 84 and 98% of the cases. Additional recorded motions were mainly related to leg movements or arousals. CONCLUSION: In this small feasibility study, Heasys(®) seemed to be an effective innovative device allowing bed-exit events detection in adult patients and healthy volunteers.