ObjectiveTo analyze the the characteristics of pulse oximetry (SpO2) curve changes in patients with obstructive sleep apnea (OSA), hypoxic parameters and to explore the difference and connection between obstructive apnea (OA) events and hypopnea (Hyp) events, evaluate the impact of different types of obstructive respiratory events on hypoxia, and provide a theoretical basis for exploration of hypoxic differences in each type of respiratory events and construction of prediction models for respiratory event types in the future. MethodsSixty patients with OSA diagnosed by polysomnography (PSG) were selected for retrospective analysis, and all respiratory events with oxygen drop in the recorded data overnight were divided into OA group (5972) according to the type of events and Hyp group (4110), recorded and scored events were exported from the PSG software as comma-separated variable (.csv) files, which were then imported and analyzed using the in-house built Matlab software. Propensity score matching was performed on the duration of respiratory events and whether they were accompanied by arousal in the two groups, and minimum oxygen saturation of events (e-minSpO2), the depth of desaturation (ΔSpO2), the duration of desaturation and resaturation (DSpO2), the duration of desaturation (d.DSpO2), duration of resaturation (r.DSpO2), duration of SpO2<90% (T90), duration of SpO2<90% during desaturation (d.T90), duration of SpO2<90% during resaturation (r.T90), area under the curve of SpO2<90% (ST90), area under the curve of SpO2<90% during desaturation (d.ST90), area under the curve of SpO2<90% during resaturation (r.ST90), oxygen desaturation rate (ODR) and oxygen resaturation rate (ORR), a total of 13 hypoxic parameters differences. ResultsVarious hypoxic parameters showed that more severe SpO2 desaturation in severe OSA patients, compared with mild and moderate OSA patients (P<0.05); There were statistically significant differences in the respiratory events duration and whether accompanied by arousal between the Hyp group and OA group (P<0.05), and the respiratory events duration and whether accompanied by arousal were significantly correlated with most hypoxic parameters; After accounting for respiratory events duration and whether accompanied by arousal by propensity score matching, compared with the Hyp group, e-minSpO2 was significantly lower in the OA group, ΔSpO2, d.DSpO2, r.DSpO2, ODR, ORR, T90, d.T90, r.T90, ST90, d.ST90, r.ST90 were significantly increased (P<0.05). ConclusionsDue to pathophysiological differences, all hypoxic parameters suggest that OA events will result in a more severe desaturation than Hyp events. Clinical assessment of OSA severity should not equate OA with Hyp events, which may cause more damage to the organism, establishing a basis for applying nocturnal SpO2 to automatically identify the type of respiratory event.
We applied Lempel-Ziv complexity (LZC) combined with brain electrical activity mapping (BEAM) to study the change of alertness under sleep deprivation in our research. Ten subjects were involved in 36 hours sleep deprivation (SD), during which spontaneous electroencephalogram (EEG) experiments and auditory evoked EEG experiments-Oddball were recorded once every 6 hours. Spontaneous and evoked EEG data were calculated and BEAMs were structured. Results showed that during the 36 hours of SD, alertness could be divided into three stages, i.e. the first 12 hours as the high stage, the middle 12 hours as the rapid decline stage and the last 12 hours as the low stage. During the period SD, LZC of Spontaneous EEG decreased over the whole brain to some extent, but remained consistent with the subjective scales. By BEAMs of event related potential, LZC on frontal cortex decreased, but kept consistent with the behavioral responses. Therefore, LZC can be effective to reflect the change of brain alertness. At the same time LZC could be used as a practical index to monitor real-time alertness because of its simple computation and fast calculation.
Objective To explore effects of edaravone on apoptosis and expressions of apoptotic proteins Smac and XIAP in hippocampal CA1 pyramidal cell of rats under intermittent hypoxia. Methods A total of 96 adult male Wistar rats were randomly divided into control group, 5% intermittent hypoxic group and edaravone group, and each group was divided into 4 time groups at 7 d, 14 d, 21 d and 28 d, respectively, with 8 rats in each subgroup. The content of reactive oxygen species (ROS) in hippocampal tissues of the experimental rats was detected by the reactive oxygen species detection kit. Immunohistochemistry and Western blot were used to detect the expressions of Smac and XIAP protein in hippocampal CA1 region. The Tunel method detected the apoptosis of neurons. Results Compared with the control group, the content of ROS, the expressions of Smac and XIAP proteins and the neuronal apoptosis index in the hippocampus were increased in the 5% intermittent hypoxia group and the edaravone group at each time point (all P<0.05). The content of ROS, the Smac protein expression and the neuronal apoptosis index in the edaravone group were significantly lower than those in the 5% intermittent hypoxia group (all P<0.05). The expression of XIAP protein in the edaravone group was significantly higher than that in the 5% intermittent hypoxia group (P<0.05). Conclusion Edaravone may improve the antioxidant capacity of the body by scavenging oxygen free radicals and regulate Smac and XIAP- mediated apoptosis, thus playing a protective role on neurons.
The quality of sleep has a great relationship with health and working efficiency. The result of sleep stage classification is an important indicator to measure the quality of sleep, and it is also an important way to diagnose and treat sleep disorders. In this paper, the method of detrended cross-correlation analysis (DCCA) was used to analyze sleep stage classification, sleep electroencephalograph signals, which were extracted from the MIT-BIH Polysomnographic Database randomly. The results showed that the average DCCA exponent of the awake period is smaller than that of the first stage of non-rapid eye movement (NREM) sleeps. It is well concluded that the method of studying the sleep electroencephalograph with this method is of great significance to improve the quality of sleep, to diagnose and to treat sleep disorders.
Objective To investigate the effect of continuous positive airway pressure (CPAP) on sleep disorder and neuropsychological characteristics in patients with early Alzheimer’s disease (AD) combined with obstructive sleep apnea hypopnea syndrome (OSAHS). Methods A total of forty-two early AD patients with OSAHS were randomly divided into a CPAP combined treatment group (20 cases) and a simple medicine treatment group (22 cases). The changes of neurocognitive function were assessed by Montreal Cognitive Assessment (MoCA), Mini-mental State Examination (MMSE) and Hopkins Verbal Learning Test-revised (HVLT). Patient Health Questionnaire-9 (PHQ9) was used to evaluate the depression mood changes. The sleep characteristics and respiratory parameters were evaluated by polysomnography. The changes of the patients’ sleep status were assessed by Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI). The changes of sleep status, cognitive function and mood in the CPAP combined treatment group were compared before and three months after CPAP treatment, and with the simple medicine treatment group. Results After three months of CPAP treatment, the ESS, PSQI and PHQ9 scores in the CPAP combined treatment group were significantly decreased compared with those before treatment, whereas MoCA, MMSE and HVLT (total scores and recall ) in the CPAP combined treatment group were increased compared with those before treatment (P<0.05). After CPAP treatment, the respiratory parameters apnea hypopnea index in the CPAP combined treatment group was significantly lower than that before treatment (P<0.05), and the minimum blood oxygen saturation was significantly higher than that before treatment (P<0.05). However, the sleep characteristics and parameters did not show statistically significant changes compared with those before treatment (P>0.05). The ESS, PSQI and PHQ9 scores were significantly reduced in the CPAP combined treatment group compared with the simple medicine treatment group (P<0.05), while there was no statistically significant changes of cognitive scores between the two groups (P>0.05). Conclusions The degree of low ventilation and hypoxia is alleviated, and the daytime sleepiness and depression is improved in early AD patients with OSAHS after three-month continuous CPAP treatment. Cognitive function is significantly improved, whereas there is no significant change in sleep structure disorder.
ObjectiveTo investigate the effects and clinical significance of edaravone on serum tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1) in elderly patients with obstructive sleep apnea hypopnea syndrome (OSAHS).MethodsA total of 90 elderly patients with moderate to severe OSAHS confirmed by polysomnography were recruited from North China University of Science and Technology Affiliated Hospital in February 2016 to October 2017. According to random number table method the OSAHS patients were randomly divided into group A (n=30), group B (n=30) and group C (n=30). Group A received continuous positive airway pressure treatment for six months, group B received edaravone therapy and continuous positive airway pressure treatment for six months, and group C only received edaravone therapy for six months. The changes of serum TNF-α, IL-6 and ICAM-1 were detected by enzyme-linked immunosorbent assay before and after treatment.ResultsThe differences of serum TNF-α, IL-6 and ICAM-1 before treatment in the three groups were not statistically significant (P>0.05). Compared with before treatment, the levels of serum TNF-α, IL-6 and ICAM-1 decreased in the three groups (P<0.05). After six months of treatment, the levels of serum TNF-α, IL-6 and ICAM-1 decreased in group A and group B compared with group C (P<0.05), and decreased significantly in group B compared with group A (P<0.05).ConclusionEdaravone can inhibit the expressions of serum TNF-α, IL-6 and ICAM-1 in elderly patients with moderate to severe OSAHS, and thereby reduce vascular endothelial dysfunction and injury.
Mental fatigue is an important factor of human health and safety. It is important to achieve dynamic mental fatigue detection by using electroencephalogram (EEG) signals for fatigue prevention and job performance improvement. We in our study induced subjects' mental fatigue with 30 h sleep deprivation (SD) in the experiment. We extracted EEG features, including relative power, power ratio, center of gravity frequency (CGF), and basic relative power ratio. Then we built mental fatigue prediction model by using regression analysis. And we conducted lead optimization for prediction model. Result showed that R2 of prediction model could reach to 0.932. After lead optimization, 4 leads were used to build prediction model, in which R2 could reach to 0.811. It can meet the daily application accuracy of mental fatigue prediction.
Sleep apnea (SA) detection method based on traditional machine learning needs a lot of efforts in feature engineering and classifier design. We constructed a one-dimensional convolutional neural network (CNN) model, which consists in four convolution layers, four pooling layers, two full connection layers and one classification layer. The automatic feature extraction and classification were realized by the structure of the proposed CNN model. The model was verified by the whole night single-channel sleep electrocardiogram (ECG) signals of 70 subjects from the Apnea-ECG dataset. Our results showed that the accuracy of per-segment SA detection was ranged from 80.1% to 88.0%, using the input signals of single-channel ECG signal, RR interval (RRI) sequence, R peak sequence and RRI sequence + R peak sequence respectively. These results indicated that the proposed CNN model was effective and can automatically extract and classify features from the original single-channel ECG signal or its derived signal RRI and R peak sequence. When the input signals were RRI sequence + R peak sequence, the CNN model achieved the best performance. The accuracy, sensitivity and specificity of per-segment SA detection were 88.0%, 85.1% and 89.9%, respectively. And the accuracy of per-recording SA diagnosis was 100%. These findings indicated that the proposed method can effectively improve the accuracy and robustness of SA detection and outperform the methods reported in recent years. The proposed CNN model can be applied to portable screening diagnosis equipment for SA with remote server.
ObjectiveTo explore the potential relationship between sleep apnea characterized by different Sleep Apnea subtype and cardiac structure and function.MethodsBased on the composition of sleep respiratory events, this study aimed to analyze whether patients with different subtype of sleep apnea exhibit specific cardiac structural characteristics. A retrospective analysis was conducted on 223 patients admitted to Guangdong Provincial Hospital of Traditional Chinese Medicine between 2018 and 2024 who completed polysomnography (PSG) and echocardiography. Participants were categorized into four groups based on respiratory event: ① with Cheyne-Stokes respiration Events (CSB), ② with central sleep apnea events and without CSB Event (ICA), ③ with obstructive sleep apnea events mainly (IOA), ④ non-sleep apnea controls (NSA), and observed the correlation of PSG parameters and echocardiographic.ResultsPatients with sleep apnea accompanied by CSR were older (χ2=36.014, P<0.001) and exhibited significantly larger left atrial diameter (χ2=41.823, P<0.001) and left ventricular end-systolic diameter (χ2=20.397, P<0.001) compared to other groups. Other sleep apnea subtypes demonstrated varying degrees of increased interventricular septal thickness (χ2=25.272, P<0.001) and left ventricular wall thickness (χ2=21.650, P<0.001) relative to non-apneic controls.ConclusionsAll sleep apnea subtypes are associated with hypertension-related cardiac structural alterations. Notably, patients with CSR-complicated sleep apnea exhibit more severe cardiac remodeling, leading to impaired systolic and diastolic functions.
Objective To explore the correlation between physical activity, sleep and aging using a two-sample Mendelian randomization (MR) method. Methods The data through genome-wide association studies was summarized. The single nucleotide polymorphisms (SNPs) related to physical activity and sleep as instrumental variables was selected. The inverse variance weighting method was used for the main analyses, complemented by the weighted median method and MR Egger regression, and then sensitivity analyses were carried out in terms of multiplicity, heterogeneity and leave-one-out method. Finally, multivariate Mendelian methods were applied to eliminate confounders and find mediators. Results A total of two types of physical activity (strong physical activity, physical inactivity) and three sleep conditions (daytime naps, short sleep duration, adequate sleep duration) were found to have a causal relationship with frailty index (P<0.05), while physical inactivity was found to have a causal relationship with telomere length (P<0.05). A total of 167 SNPs were included in the analysis. Strong physical activity [correlation coefficient (β)=?1.26, 95% confidence interval (CI) (?1.60, ?0.96), P<0.0001], adequate sleep duration [β=?0.17, 95%CI (?0.26, ?0.09), P<0.001] were negatively correlated with the frailty index. Physical inactivity [β=1.47, 95%CI (0.85, 2.08), P<0.001], daytime naps [β=0.25, 95%CI (0.12, 0.39), P=0.0002], and short sleep duration [β=0.20, 95%CI (0.13, 0.27), P<0.0001] were positively associated with frailty index. Physical inactivity [β=?0.38, 95%CI (?0.69, ?0.07), P=0.02] was negatively correlated with telomere length. Percentage body fat, body fat mass, waist circumference, body weight and body mass index partially mediated 25.52%, 23.52%, 10.08%, 17.6% and 10.08% of the effect between daytime naps and frailty index, respectively. Conclusion There is a causal relationship between physical activity, sleep, and aging.