Implications of depressive mood in OSAHS patients: insights from event-related potential.

BACKGROUND: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a chronic breathing disorder characterized by recurrent upper airway obstruction during sleep. Although previous studies have shown a link between OSAHS and depressive mood, the neurobiological mechanisms underlying mood disorders in OSAHS patients remain poorly understood. This study aims to investigate the emotion processing mechanism in OSAHS patients with depressive mood using event-related potentials (ERPs). METHODS: Seventy-four OSAHS patients were divided into the depressive mood and non-depressive mood groups according to their Self-rating Depression Scale (SDS) scores. Patients underwent overnight polysomnography and completed various cognitive and emotional questionnaires. The patients were shown facial images displaying positive, neutral, and negative emotions and tasked to identify the emotion category, while their visual evoked potential was simultaneously recorded. RESULTS: The two groups did not differ significantly in age, BMI, and years of education, but showed significant differences in their slow wave sleep ratio (P = 0.039), ESS (P = 0.006), MMSE (P < 0.001), and MOCA scores (P = 0.043). No significant difference was found in accuracy and response time on emotional face recognition between the two groups. N170 latency in the depressive group was significantly longer than the non-depressive group (P = 0.014 and 0.007) at the bilateral parieto-occipital lobe, while no significant difference in N170 amplitude was found. No significant difference in P300 amplitude or latency between the two groups. Furthermore, N170 amplitude at PO7 was positively correlated with the arousal index and negatively with MOCA scores (both P < 0.01). CONCLUSION: OSAHS patients with depressive mood exhibit increased N170 latency and impaired facial emotion recognition ability. Special attention towards the depressive mood among OSAHS patients is warranted for its implications for patient care.

Excessive daytime sleepiness in young and middle-aged Chinese adults with obstructive sleep apnea: implications for cognitive dysfunction.

OBJECTIVE: The objective of this study was to investigate the effects of excessive daytime sleepiness (EDS) on cognitive function among Chinese young and middle-aged Chinese patients with obstructive sleep apnea (OSA). METHODS: Chinese adults struggling from moderate to severe OSA with apnea-hypopnea index (AHI) ≥ 15 events per hour and adults with primary snoring and mild OSA (AHI < 15 events per hour) were included in the study. The Epworth Sleepiness Scale measured hypersomnia, and cognitive function was assessed using the Mini-mental State Examination (MMSE) and Montreal Cognitive Assessment (MOCA). RESULTS: In comparison to the primary snoring and mild OSA group (n=635), the moderate to severe OSA group (n=1423) tended to be older men with higher scores on the Epworth Sleepiness Scale (ESS), as well as higher levels of oxygen desaturation (ODI) and a higher body mass index (BMI). Patients with moderate to severe OSA had fewer years of education, lower minimum arterial oxygen saturation (min-SaO2), and more severe sleep disturbances, such as decreased slow wave sleep (SWS) and rapid eye movement (REM) and increased non-REM stages (N1 and N2). Comorbid conditions such as hypertension and diabetes mellitus were more common in these patients (P < 0.01 and P < 0.05, accordingly). Only the delayed recall scores were statistically lower in the moderate to severe OSA group than the primary snoring and mild OSA group (P < 0.05). The main factor associated with delayed recall was the ESS score rather than age or years of education among moderate-severe OSA patients ≤ 40 years of age (P < 0.05). After controlling for potential confounding factors such as age, gender, BMI, education, hypertension, diabetes, sleep stages (SWS and REM), minimum arterial oxygen saturation (min-SaO2), oxygen ODI, and AHI, there was a negative correlation between the Epworth Sleepiness Scale (ESS) score and the delayed recall scores. CONCLUSION: Patients with moderate to severe OSA had cognitive dysfunction, particularly impairment of delayed recall. Excessive daytime sleepiness (EDS) was significantly associated with cognitive dysfunction in young and middle-aged patients with OSA.

Transcranial magnetic stimulation cortical oscillations and improve cognition in obstructive sleep apnea patients.

BACKGROUND: Transcranial magnetic stimulation (TMS) is a noninvasive tool to improve cognition. Relevant clinical studies are mainly focused on neurological and psychiatric diseases. However, cognition decline and psychiatric disorders are popular in obstructive sleep apnea (OSA) patients. We aimed to investigate the effect of TMS over the left dorsolateral prefrontal cortex (DLPFC) on cognition test performance and to compare the changes in quantitative electroencephalogram (EEG) before and after stimulation for OSA. METHODS: This study recruited 42 OSA patients diagnosed with polysomnography according to American Academy of Sleep Medicine guidelines. TMS (intermittent theta-burst stimulation paradigm; 2 s on, 8 s off, 600 pulses*3, intermittent 15 min) was performed on the DLPFC. Cambridge Automated Neuropsychological Test Battery was used to assess cognitive performance. EEG oscillations were computed via power spectral density with MATLAB software. RESULTS: Real-TMS group displayed a significant improvement in visual memory, sustain attention performance, as well as the outcome of working memory. However, the executive function of latency was changed in both groups. Furthermore, TMS resulted in a significant increase in the relative power spectral density of the theta band and beta band in the parietal, temporal, and anterior regions, respectively. CONCLUSIONS: In summary, our findings indicate that TMS can safely modulate cortical oscillations and improve cognition in OSA patients. In the future, TMS can be utilized as an alternative treatment option to improve cognition in OSA patients.

Multi-Response Robust Parameter Optimization of Cemented Backfill Proportion with Ultra-Fine Tailings.

Backfill of mined-out areas in Carlin-type gold mines always encounters the challenges of ultra-fine tailings, low backfill strength and difficult slurry transportation caused by fine tailings. To understand the influence of slurry mass concentration, waste rock content, and cement-sand ratio on the cemented backfill strength and fluidity, influential factors were determined by range analysis of orthogonal proportion experiments. Response surface methodology (RSM) was used to analyze the influence of each factor on response, and the backfill strength and slump were optimized using a robust optimization desirability function method. The results show that the cement-sand ratio has the highest effect on the backfill strength, and the slurry slump is dominated by the slurry mass concentration. The interaction between waste rock content and the cement-sand ratio significantly impacts the slump, while the interaction between the slurry mass concentration and the cement-sand ratio has a positive correlation with the backfill strength. The ultra-fine tailings cemented backfill proportion was optimized by using multi-response robust parameters as 68.36% slurry mass concentration, 36.72% waste rock content and 1:3 cement-sand ratio. The overall robust optimal desirability was 0.8165, and the validity of multi-response robust parameter optimization was verified by laboratory tests.

Predictors of the Efficacy for Daytime Sleepiness in Patients With Obstructive Sleep Apnea With Continual Positive Airway Pressure Therapy: A Meta-Analysis of Randomized Controlled Trials.

Objective: The main aim of this meta-analysis was to evaluate the predictors of the efficacy of continuous positive airway pressure (CPAP) in ameliorating excessive daytime sleepiness (EDS) in patients with obstructive sleep apnea (OSA). Methods: Randomized controlled trials (RCTs) published between January 1994 and October 2021 were searched in the PubMed, EMBASE, and Cochrane Library databases. The weighted mean differences (WMDs) for the Epworth Sleepiness Scale (ESS) scores, the Multiple Sleep Latency Test (MSLT), and the Maintenance of Wakefulness Test (MWT) were pooled in STATA. Results: A total of 41 RCTs involving 7,332 patients were included. CPAP therapy was found to be significantly associated with changes in ESS (WMD = -2.14, P < 0.001), MSLT (WMD = 1.23, P < 0.001), and MWT (WMD = 1.6, P < 0.001). Meta-regression analysis and subgroup analysis indicated that in mild OSA, the efficacy of CPAP therapy for subjective EDS was limited to patients <50 years of age, with a baseline body mass index (BMI) of ≥30 kg/m2, baseline ESS score of ≥11, therapy adherence for ≥3 h/night, and treatment duration of ≥2 months. In moderate OSA, significant differences were observed in the changes in ESS among groups stratified by baseline ESS score (P = 0.005), adherence (P < 0.001), treatment duration (P = 0.009), and trial design type (P = 0.001). In severe OSA, this difference was observed among groups stratified by baseline BMI (P = 0.028), baseline ESS score (P = 0.001), and adherence (P = 0.047). Patients with moderate-severe OSA but not mild OSA showed significant improvements in MSLT. Patients with the age <50 years or BMI ≥33 kg/m2 had a more significant increase in MWT. Conclusion: Continuous positive airway pressure therapy improved subjective and objective sleepiness in patients with OSA. Age, baseline BMI, baseline ESS score, adherence, and duration of treatment may predict the effects of CPAP on EDS in patients with OSA. Notably, the baseline ESS scores and adherence were stable predictors regardless of OSA severity.

Association of mental health with clinical outcomes in hospitalized patients with moderate COVID-19.

OBJECTIVE: To assess the association of depression and anxiety with clinical outcomes and laboratory markers among hospitalized patients with coronavirus disease 2019 (COVID-19). METHODS: A prospective cohort study in Wuhan, China was conducted in 205 adult hospitalized patients with a diagnosis of moderate coronavirus disease from admission through discharge or death. Anxiety and depression were assessed using the Hospital Anxiety and Depression Scale (HADS). The primary outcome was the incidence of severe or critical COVID-19, and the secondary outcomes were increased length of hospital stay and altered laboratory markers during follow up. RESULTS: Among the 205 hospitalized patients (mean age 58 years; 51.7% male), 25 (12.2%) developed severe or critical COVID-19. According to the HADS scores, 51 (24.9%) and 92 (44.9%) of participants presented with clinically significant anxiety and depression, respectively. Using multi-variable adjusted Cox regression analysis, the adjusted hazard ratio of developing severe or critical COVID-19 associated with anxiety and depression was 1.55 (95% CI: 0.63, 3.80) and 4.28 (95% CI: 1.20, 15.30), respectively. The risk of developing severe or critical COVID-19 with both anxiety and depression was more than four times higher than in patients without anxiety or depression (HR, 4.05; 95% CI: 1.02, 16.00). In addition, both the trends of depression and anxiety were positively associated with a prolonged duration of hospitalization, and immune response was significantly decreased in patients with depression than those without. CONCLUSIONS: In patients having coronavirus disease, depression was associated with worse clinical outcomes. These findings highlight the importance of prevention and management of mental health problems in confronting the COVID-19 pandemic.

Association of sleep quality before and after SARS-CoV-2 infection with clinical outcomes in hospitalized patients with COVID-19 in China.

Sleep is believed to benefit the host defense against pathogens. We aimed to investigate the association of sleep quality with clinical outcomes among hospitalized patients with COVID-19. We conducted a prospective cohort study in 205 adult hospitalized patients with diagnosed moderate COVID-19, with follow-up until hospital discharge or death. Pittsburgh Sleep Quality Index (PSQI) assessed sleep quality before and after infection. The primary outcome was the incidence of severe or critical pneumonia, and the secondary outcomes were duration of hospital stay and laboratory measurements during the follow up. Among the 205 included hospitalized patients, 185 (90.2 %) experienced poorer sleep quality after infection than before according to the PSQI score, and 25 (12.2 %) developed severe or critical pneumonia during follow-up. In Cox regression models, the adjusted hazard ratio of developing severe or critical pneumonia associated with each 1 score increment in the PSQI score before and after infection was 1.23 (95% CI: 1.09, 1.39) and 1.35 (95 % CI: 1.08, 1.67), respectively. Poorer sleep quality was also significantly associated with a prolonged hospital stay and more serious dysregulations in immune system indicated by several laboratory markers. Poorer sleep quality, either in the daily time or after infection with SARS-CoV-2, was associated with worse clinical outcomes. These findings highlight the importance of good sleep in confronting the emerging pandemic of COVID-19.

Analysis of factors affecting measurement accuracy and establishment of an optimal measurement strategy of a laser displacement sensor.

Laser triangulation method is widely used in online precision measurement owing to its advantages of being fast, accurate, and dynamic, and having large-scale measurement capability. To improve the accuracy of laser triangulation, the scan depth, inclination angle, rotation angle, and deflection angle are defined. Then, a spatial pose error model and an experimental model for laser measurement error are established. Next, error analysis experiments are conducted, and the influence of spatial pose parameters on the error is analyzed. Further, error proofreading experiments on the surface characteristics of the measured workpiece, including the material, surface roughness, and color, are completed, and their influences on the error are analyzed. Based on the experimental data, an error correction model based on support vector regression is established. Measurement strategies are formulated considering multi-factor constraints such as optical path interference, mechanical interference, scan depth of field, measurement angle, and measurement path. The tooth profile of a cycloid gear is taken as the measurement object, then the measurement path planning is performed, and the error correction model is used to correct the measured data. The accuracy of the results agrees well with the result of a fully automatic computer numerical control (CNC)-controlled P 65 precision measuring center.

Characteristics of Sleep Structure Assessed by Objective Measurements in Patients With Amnestic Mild Cognitive Impairment: A Meta-Analysis.

Objectives: This study aims to explore the differences of sleep structure between patients with amnestic mild cognitive impairment (aMCI) and elderly people with normal cognition, which will help to provide evidence for the relationship between sleep disturbances and cognitive impairment. Methods: A systematic review and meta-analysis were conducted on the literature on sleep parameters obtained by polysomnography or actigraphy in patients with aMCI. The PubMed and EMBASE databases were searched up to April 2020. Inclusion and exclusion criteria were established according to evidence-based medicine methods, and data of all eligible studies were meta-analyzed using the Review Manager 5.3 software. Results: Among the 1,171 literature articles on sleep structure of patients with MCI, eight case-control studies met the inclusion criteria and were included in this meta-analysis. A total of 278 subjects were included, of which 103 were patients with aMCI and 175 were elderly people with normal cognition. The results showed that sleep efficiency (SE) and slow wave sleep (SWS) of patients with aMCI were significantly lower than those of healthy elderly people. Compared with the control group, the percentage of stage 1 of non-rapid eye movement (N1%) in the aMCI patients group increased, and the percentage of stage 2 of non-rapid eye movement (N2%) decreased. Conclusions: Patients with aMCI may experience more severe sleep disturbances than normal cognitive elderly people. There were specific changes, especially in SE and SWS, in the sleep structure of patients with aMCI when compared to those with normal cognition.

Optical Coherence Tomography Angiography in Pinguecula and Pterygium.

PURPOSE: To investigate the density of conjunctival blood vessels in normal eyes and in eyes with pinguecula or pterygium. METHODS: In this cross-sectional study, the conjunctival blood vessel density of 15 normal eyes, 15 pinguecula eyes, and 15 pterygium eyes of 43 healthy adults was assessed using optical coherence tomography angiography with an anterior segment lens adapter. The nasal surface of each eye (3 × 3 mm) was scanned 3 times to a depth of 800 µm. Conjunctival vessel density was defined as the percent of the scanned volume occupied by vessels in which blood flow was measured. RESULTS: The high reliability of data measurement was supported by good coefficients of repeatability (<10%) of the image quality score and high intraclass correlation coefficients (>0.9). The vessel density in normal conjunctivas, 52.2 ± 4.1%, was similar to that in pinguecula conjunctivas, 50.5 ± 4.7% (P = 0.3006). However, the vessel density in conjunctivas with pterygium, 63.6 ± 3.7%, was greater than that in either normal (P < 0.0001) or pinguecula (P < 0.0001) conjunctivas. CONCLUSIONS: Using optical coherence tomography angiography with an anterior segment lens adapter, the ocular surface blood vessel density was imaged and assessed with good repeatability and reliability. The blood vessel density of conjunctivas with pterygium was significantly greater than that in either normal or pinguecula conjunctivas. This suggests that, in contrast to pinguecula development, pterygium development includes angiogenesis and neovascularization.

Repeatability of ocular surface vessel density measurements with optical coherence tomography angiography.

BACKGROUND: To determine the repeatability of measurements of ocular surface vessel density in normal and diseased eyes using optical coherence tomography angiography (OCTA). METHODS: Ten normal eyes, 10 pinguecula eyes, and 10 pterygium eyes of 30 volunteers were subjected to OCTA (AngioVue Imaging System, Optovue, Inc.). For scanning, we used the corneal adapter module. Each eye was scanned three times in the nasal and temporal directions, separately. AngioVue software was used to generate the ocular surface vessel density. Ocular surface vessel density was defined as the proportion of vessel area with blood flow to the total measurement area (3 × 3 mm2). Intersession repeatability of the measurement was summarized as the coefficient of variation (CV), and intraclass correlation coefficients (ICC) were calculated by variance component models. RESULTS: The CVs were less than 5% in all subjects, and the ICCs exceeded 0.9; thus, all measurements showed good repeatability. The nasal vessels densities differed significantly between healthy eyes and eyes with pterygium (P < 0.05); however, there was no significant difference between healthy eyes and eyes with pinguecula (P = 0.466). CONCLUSIONS: These results suggest that measurement of ocular surface vessel density by OCTA in normal eyes and eyes with pterygium and pinguecula is repeatable. This preliminary research describes a quantitative and visual method for assessing vessel density of the ocular surface with a high level of consistency.

Obstructive sleep apnea exaggerates cognitive dysfunction in stroke patients.

BACKGROUND: Obstructive sleep apnea (OSA) is very common in stroke survivors. It potentially worsens the cognitive dysfunction and inhibits their functional recovery. However, whether OSA independently damages the cognitive function in stroke patients is unclear. A simple method for evaluating OSA-induced cognitive impairment is also missing. METHODS: Forty-four stroke patients six weeks after onset and 24 non-stroke patients with snoring were recruited for the polysomnographic study of OSA and sleep architecture. Their cognitive status was evaluated with a validated Chinese version of Cambridge Prospective Memory Test. The relationship between memory deficits and respiratory, sleeping, and dementia-related clinical variables were analyzed with correlation and multiple linear regression tests. RESULTS: OSA significantly and independently damaged time- and event-based prospective memory in stroke patients, although it had less power than the stroke itself. The impairment of prospective memory was correlated with increased apnea-hypopnea index, decreased minimal and mean levels of peripheral oxygen saturation, and disrupted sleeping continuity (reduced sleep efficiency and increased microarousal index). The further regression analysis identified minimal levels of peripheral oxygen saturation and sleep efficiency to be the two most important predictors for the decreased time-based prospective memory in stroke patients. CONCLUSIONS: OSA independently contributes to the cognitive dysfunction in stroke patients, potentially through OSA-caused hypoxemia and sleeping discontinuity. The prospective memory test is a simple but sensitive method to detect OSA-induced cognitive impairment in stroke patients. Proper therapies of OSA might improve the cognitive function and increase the life quality of stroke patients.

Correlation of Epworth Sleepiness Scale with multiple sleep latency test and its diagnostic accuracy in assessing excessive daytime sleepiness in patients with obstructive sleep apnea hypopnea syndrome.

BACKGROUND: Excessive daytime sleepiness (EDS) is often associated with obstructive sleep apnea hypopnea syndrome (OSAHS) and contributes to a number of comorbidities in these patients. Therefore, early detection of EDS is critical in disease management. We examined the association between Epworth Sleepiness Scale (ESS) and multiple sleep latency test (MSLT) and diagnostic accuracy of ESS in assessing EDS in OSAHS patients. METHODS: The ESS, MSLT and overnight polysomnography were administered to 107 Chinese patients to assess EDS and its correlations with polysomnographic parameters. The diagnostic accuracy of ESS in classifying EDS (mean sleep latency (MSL) ≤ 10 minutes) was evaluated by calculating the area under ROC curve. RESULTS: As the severity of OSAHS increased, MSL decreased with increase in ESS score. Conversely, patients with worsening EDS (shorter MSL) were characterized by advanced nocturnal hypoxaemia and sleep disruption compared to those with normal MSL, suggesting EDS is associated with more severe OSAHS. There was a negative correlation between ESS score and MSL and both moderately correlated with some polysomnographic nocturnal hypoxaemic parameters. The area under ROC curve of ESS for identifying EDS was 0.80 (95% CI: 0.71 to 0.88) and ESS score ≥ 12 provided the best predictive value with a sensitivity of 80% and specificity of 69%. CONCLUSION: The ESS score moderately correlates with MSL and our ROC study supports ESS as a screening strategy for assessing EDS in OSAHS.