OBJECTIVE: Reduce the number of false alarms and measurement time caused by movement interference by the sync waveform of the movement. METHODS: Vital signal monitoring system based on motion sensor was developed, which collected and processed the vital signals continuously, optimized the features and results of vital signals and transmitted the vital signal results and alarms to the interface. RESULTS: The system was tested in many departments, such as digestive department, cardiology department, internal medicine department, hepatobiliary surgery department and emergency department, and the total collection time was 1 940 h. The number of false electrocardiograph (ECG) alarms decreased by 82.8%, and the proportion of correct alarms increased by 28%. The average measurement time of non-invasive blood pressure (NIBP) decreased by 16.1 s. The total number of false respiratory rate measurement decreased by 71.9%. CONCLUSIONS False alarms and measurement failures can be avoided by the vital signal monitoring system based on accelerometer to reduce the alarm fatigue in clinic.
Humans ; Monitoring, Physiologic ; Electrocardiography ; Arrhythmias, Cardiac ; Blood Pressure ; Accelerometry ; Clinical Alarms

OBJECTIVE: To explore the differences of alignment and operative time between portable accelerometer-based navigation device (PAD) and computer assisted surgery (CAS) in total knee arthroplasty (TKA). METHODS: Data of patients using iASSIST (a kind of PAD) and OrthoPilot (a kind of CAS) for TKA in Peking University Third Hospital from December 2017 to December 2019 were retrospectively collected. The differences of preoperative general data, preoperative alignment, operative time and postoperative alignment were studied between the two groups. RESULTS: A total of 82 patients were enrolled in our study, including 40 patients in the PAD group and 42 patients in the CAS group. Gender, age, body mass index (BMI), surgical side, preoperative hip-knee-ankle (HKA) angle and preoperative HKA angle deviation didn't show statistically significant difference between the PAD group and the CAS group (P>0.05). Postoperative HKA angle (180.8°±2.2° vs.181.8±1.6°, t=－2.458, P=0.016) and postoperative coronal femoral-component angle (CFA, 90.6°±1.8° vs. 91.6°±1.6°, t =－2.749, P=0.007) of the PAD group were smaller than those of the CAS group, but there was no significant difference in coronal tibia-component angle (CTA, 90.0°±1.3° vs.89.6°±1.4°, t=1.335, P=0.186) between the two groups. There was no significant difference in the rate of outliers (varus or valgus > 3°) for postoperative HKA angle (10.0% vs.11.9%, χ² =0.076, P=0.783), CFA (12.5% vs. 14.3%, χ²=0.056, P=0.813) and CTA (2.5% vs. 0%, χ²=1.063, P=0.303). There was no significant difference in the accuracy of postoperative HKA angle (2.1° vs. 2.0°, t=0.055, P=0.956), CFA (1.4° vs. 1.8°, t=－1.365, P=0.176) and CTA (1.0° vs. 1.1°, t=－0.828, P=0.410) between the two groups. The precision of postoperative HKA angle (1.1° vs. 1.3°, F=1.251, P=0.267), CFA (1.3° vs. 1.4°, F=0.817, P=0.369) and CTA (0.8° vs. 0.9°, F=0.937, P=0.336) were also not significantly different. We also didn't find statistically significant difference in operative time between the two groups [(83.4±25.6) min vs. (86.5±17.7) min, t=－0.641, P=0.524]. CONCLUSION PAD and CAS had similar accuracy and precision in alignment in TKA, and there was no significant difference in operative time, which indicates that PAD has a broad application prospect in TKA.
Accelerometry ; Arthroplasty, Replacement, Knee ; Humans ; Knee Joint/surgery* ; Operative Time ; Osteoarthritis, Knee ; Retrospective Studies ; Surgery, Computer-Assisted ; Tibia/surgery*

OBJECTIVE: With the rapid development of sleep medicine, there are various methods for detecting sleep diseases. This study compared the correlation between the lightweight watch-type sleep monitor (Actiwatch) and the "gold standard" polysomnography (PSG) in the Chinese population, in order to provide a basis for clinical application. METHODS: From August 2018 to December 2019, 121 subjects who simultaneously performed sleep breathing monitoring (PSG) and wearing a watch-type sleep monitor (Actiwatch) in the Sleep Center of Peking University People's Hospital were enrolled. All subjects received PSG and Actiwatch at the same time, and filled out the sleep diary next morning. Monitoring indicators were collected for linear correlation analysis and paired t test to compare the differences. RESULTS: Under low sensitivity conditions, the correlation coefficient of total sleep time (TST) between PSG and Actiwatch was 0.53 (P < 0.05). Paired t test analysis showed that there was no significant difference between the TSTs of Actiwatch and PSG (t=-0.890, P=0.36). According to age stratification, the smaller the age, the stronger the correlation between the TSTs of Actiwatch and PSG, and the coefficient could be up to 0.92 (P < 0.05). Paired t test showed that there was no significant difference between them (t=-1.057, P=0.35). According to the stratification by diagnosis, the correlation coefficient between the TSTs of Actiwatch and PSG in normal PSG group could be as high as 0.79 (P < 0.05), the results of paired t test showed that there was no significant difference between the TSTs of Actiwatch and PSG in normal PSG group (t=-0.784, P=0.44). CONCLUSION As a wearable home recorder, when the analysis parameters of Actiwatch were set as low sensitivity, PSG and Actiwatch had the highest TST correlation. The younger the age, the stronger correlation between the TSTs of Actiwatch and PSG. The PSG and Actiwatch subjects with normal PSG presentation had a higher TST correlation.
Actigraphy ; Humans ; Polysomnography ; Reproducibility of Results ; Sensitivity and Specificity ; Sleep ; Sleep Wake Disorders ; Time

BACKGROUND: Little is known on how context-specific sedentary behaviors (SB) affect adiposity. This study aimed to investigate compositional associations between context-specific SB and adiposity and estimate the differences in adiposity associated with replacing school and out-of-school SB with physical activity (PA). METHODS: This study included 336 children and adolescents. Time spent in SB and PA was estimated using multi-day 24-hour raw accelerometer data. SB and PA were specified for school and out-of-school times. Fat mass percentage (FM%) and fat mass index (FMI) were used as adiposity indicators. A compositional isotemporal substitution model was used to estimate differences in adiposity associated with one-to-one reallocations of time from context-specific SB to PA. RESULTS: Participants spent approximately two thirds of their school and out-of-school time being sedentary. Relative to the remaining 24-h movement behaviors, significant associations between out-of-school SB and adiposity were found in both boys (β CONCLUSIONS A reduction of out-of-school SB in favor of light PA should be advocated as an appropriate target for interventions and strategies to prevent childhood obesity.
Accelerometry ; Adiposity ; Adolescent ; Child ; Czech Republic ; Exercise ; Female ; Humans ; Male ; Schools ; Sedentary Behavior

PURPOSE: The main purpose of this study was to compare the relationships between physical activity (measured using an accelerometer vs. self-reported) and cardiovascular disease risk factors. Differences in accelerometry physical activity between 10-minute bouts and total bouts were also compared.METHODS: Data originated from the Korea National Health and Nutrition Examination Survey. Logistic regression was used to predict cardiovascular disease risk from physical activity levels.RESULTS: Self-reported physical activity could not significantly predict the odds of having cardiovascular risk. However, the insufficiently active group classified according to the total-bout physical activity had significantly greater odds of having hypertension or prehypertension (odds ratio [OR], 1.35; 95% confidence interval [95% CI], 1.00–1.82), diabetes mellitus (OR, 1.77; 95% CI, 1.01–3.19), and dyslipidemia (OR, 1.65; 95% CI, 1.17–2.36) than the highly active group. Regarding the 10-minute bout physical activity, the inactive group had significantly greater odds of having only hypertension or prehypertension (OR, 1.67; 95% CI, 1.02–2.76) than the highly active group.CONCLUSION: Total-bout physical activity measured using an accelerometer could significantly predict the cardiovascular disease risk compared to 10-minute bout physical activity. However, self-reported physical activity could not significantly predict the cardiovascular disease risk.
Accelerometry ; Cardiovascular Diseases ; Diabetes Mellitus ; Dyslipidemias ; Hypertension ; Korea ; Logistic Models ; Motor Activity ; Nutrition Surveys ; Prehypertension ; Risk Assessment ; Risk Factors ; Self Report

BACKGROUND: Few studies have examined the effects of a forward rotating shift pattern on police employee performance and well-being. This study sought to compare sleep duration, cognitive performance, and vigilance at the start and end of each shift within a three-shift, forward rotating shift pattern, common in United Kingdom police forces. METHODS: Twenty-three police employee participants were recruited from North Yorkshire Police (mean age, 43 years). The participants were all working the same, 10-day, forward rotating shift pattern. No other exclusion criteria were stipulated. Sleep data were gathered using both actigraphy and self-reported methods; cognitive performance and vigilance were assessed using a customized test battery, comprising five tests: motor praxis task, visual object learning task, NBACK, digital symbol substitution task, and psychomotor vigilance test. Statistical comparisons were conducted, taking into account the shift type, shift number, and the start and end of each shift worked. RESULTS: Sleep duration was found to be significantly reduced after night shifts. Results showed a significant main effect of shift type in the visual object learning task and NBACK task and also a significant main effect of start/end in the digital symbol substitution task, along with a number of significant interactions. CONCLUSION: The results of the tests indicated that learning and practice effects may have an effect on results of some of the tests. However, it is also possible that due to the fast rotating nature of the shift pattern, participants did not adjust to any particular shift; hence, their performance in the cognitive and vigilance tests did not suffer significantly as a result of this particular shift pattern.
Actigraphy ; Fatigue ; Great Britain ; Humans ; Learning ; Police

OBJECTIVE: To determine whether post-stroke patient’s perceived exertion correlates with effort intensity score as measured by a wearable sensor and to assess whether estimates of perceived exertion are correlated to the cerebral hemisphere involved in the stroke. METHODS: We evaluated the effort intensity score during physiotherapy sessions using a wearable sensor and subjects assessed their perceived exertion using the modified Borg CR10 Scale. RESULTS: Fifty-seven subacute stroke patients participated in the study. The correlation between perceived exertion rating and measured effort intensity was insignificant—mean (r=−0.04, p=0.78) and peak (r=−0.05, p=0.70). However, there was a significant difference (p<0.02) in the perceived exertion ratings depending on the cerebral hemisphere where the stroke occurred. Patients with left-hand side lesions rated their perceived exertion as 4.5 (min–max, 0.5–8), whereas patients with right-hand side lesions rated their perceived exertion as 5.0 (2–8). CONCLUSION: While there was an insignificant correlation between perceived exertion and effort intensity measured by a wearable sensor, a consistent variations in perceived exertion estimates according to the side of the cerebral lesion was identified and established.
Accelerometry ; Cerebrum ; Humans ; Motor Activity ; Rehabilitation ; Stroke

With progress in sensors and communication technologies, the range of sleep monitoring is extending from professional clinics into our usual home environments. Information from conventional overnight polysomnographic recordings can be derived from much simpler devices and methods. The gold standard of sleep monitoring is laboratory polysomnography, which classifi es brain states based mainly on EEGs. Single-channel EEGs have been used for sleep stage scoring with accuracies of 84.9%. Actigraphy can estimate sleep effi ciency with an accuracy of 86.0%. Sleep scoring based on respiratory dynamics provides accuracies of 89.2% and 70.9% for identifying sleep stages and sleep effi ciency, respectively, and a correlation coeffi cient of 0.94 for apnea–hypopnea detection. Modulation of autonomic balance during the sleep stages are well recognized and widely used for simpler sleep scoring and sleep parameter estimation. This modulation can be recorded by several types of cardiovascular measurements, including ECG, PPG, BCG, and PAT, and the results showed accuracies up to 96.5% and 92.5% for sleep effi ciency and OSA severity detection, respectively. Instead of using recordings for the entire night, less than 5 min ECG recordings have used for sleep effi ciency and AHI estimation and resulted in high correlations of 0.94 and 0.99, respectively. These methods are based on their own models that relate sleep dynamics with a limited number of biological signals. Parameters representing sleep quality and disturbed breathing are estimated with high accuracies that are close to the results obtained by polysomnography. These unconstrained technologies, making sleep monitoring easier and simpler, will enhance qualities of life by expanding the range of ubiquitous healthcare.
Actigraphy ; Brain ; Delivery of Health Care ; Electrocardiography ; Electroencephalography ; Mycobacterium bovis ; Polysomnography ; Respiration ; Sleep Stages

BACKGROUND AND PURPOSE: Shift work disrupts the body's circadian rhythms and increases the risk of health problems. Despite evidence of neuropsychological disturbances in shift workers (SW), the brain functional status as measured by brain perfusion in chronic shift work has not been evaluated previously. We investigated the regional cerebral blood flow (rCBF) in SW using perfusion MRI (pMRI) and evaluated the relationships between altered rCBF and sleep, mood, psychometric measures, and quality of life. METHODS: Fifteen rotational SW and 15 day workers (DW) were enrolled. The participants were all female nurses working at a university-affiliated hospital. During 2 weeks of actigraphy they underwent pMRI scanning and psychometric testing on the last day immediately after working. Demographic characteristics, insomnia, daytime sleepiness, and mood were compared between the groups. RESULTS: The participants were aged 35.3±2.9 years (mean±SD) and had been performing their current work for more than 2 years. The demographic characteristics did not differ between SW and DW, but the levels of insomnia, anxiety, depression, and hyperactivity-restlessness in psychometric measures were higher in SW than in DW. Cerebral perfusion in SW was significantly decreased in the cuneus, fusiform/parahippocampal gyri, and cerebellum of the right hemisphere, while it was increased in the inferior occipital gyrus of the left hemisphere. Perfusion changes in SW were significantly correlated with depression and insomnia severity. The onset and duration irregularity of sleep among SW were related to insomnia, mood, hyperactivity/ restlessness, and quality of life. CONCLUSIONS: SW experience considerably more insomnia and mood disturbances than do DW, and this is significantly related to perfusion changes in multiple brain areas.
Actigraphy ; Anxiety ; Brain ; Cerebellum ; Cerebrovascular Circulation ; Circadian Rhythm ; Depression ; Female ; Humans ; Magnetic Resonance Angiography ; Magnetic Resonance Imaging ; Occipital Lobe ; Perfusion ; Psychometrics ; Psychomotor Agitation ; Quality of Life ; Sleep Initiation and Maintenance Disorders

Many patients with a traumatic brain injury (TBI) experience a range of sleep problems. Although some studies investigated the pathophysiology of sleep-wake cycle disturbances in TBI patients, it has not been clarified. This paper presents a middle aged female patient who showed sleep deprivation and sleep-wake cycle disturbances for approximately three months after TBI. The improvement in the subjective and objective sleep quality was shown by the sleep diary and actigraphy during this period. Moreover, the dim light melatonin onset (DLMO) had been delayed before returning to the normal range in 3 months. In addition, the patient showed an improvement in the neurocognitive function, including attention, memory and language function, along with a consolidation of the sleep-wake cycle. This case showed that the sleep disturbance following a TBI was probably caused by the disrupted melatonin rhythm based on the abnormality of the DLMO. In addition, the cognitive dysfunction after TBI could be associated with sleep-wake cycle disturbances because its gradual improvement occurred as the sleep disturbance diminished. Further studies on the change in circadian rhythm after a brain injury related to neurocognitive impairment are required.
Actigraphy ; Brain Injuries ; Circadian Rhythm ; Female ; Humans ; Melatonin ; Memory ; Middle Aged ; Reference Values ; Sleep Deprivation