Objective Obstructive Sleep Apnea Research Articles

Parameters affecting improvement of excessive daytime sleepiness in obstructive sleep apnea patients

ObjectivesObstructive sleep apnea (OSA) is a sleep-related breathing disorder caused by repetitive obstruction of the upper airway; this impairs gaseous exchange, resulting in hypoxia, hypercapnia, and frequent arousals. Excessive daytime sleepiness (EDS) is a common daytime symptom of OSA. EDS manifests as fatigue and impaired attention, leading to poor performance at work and falling asleep while driving, which is a major socioeconomic problem. Therefore, it is important to properly treat EDS and accurately predict the response to treatment. However, few studies have compared OSA patients showing and not showing improvement in EDS. Therefore, this study aimed to objectively analyze and compare EDS improvement and non-improvement groups. Subjects and methodsWe retrospectively reviewed the medical records of 57 OSA patients with EDS. Patients were divided into two groups according to the improvement in EDS after positive airway pressure (PAP) device treatment. We analyzed differences in clinical records including patients' age, sex, history of smoking, hypertension, diabetes, myocardial infarction, and cerebrovascular disease between the two groups. Systolic, diastolic blood pressure, blood test including blood glucose, total cholesterol, high- and low-density lipoprotein cholesterol, and triglyceride levels were also analyzed. Polysomnography (PSG) data, PAP device treatment compliance and scores of questionnaires related to various psychiatric symptoms, subjective sleep quality between the two groups were also analyzed. ResultsThere was no statistically significant difference in age, gender, or past medical history between the two groups. Systolic and diastolic blood pressure, and blood test results, were also not significantly different. Among the questionnaires related to various psychiatric symptoms, the groups showed statistically significant differences in Social Avoidance and Distress Scale (SADS) and Fear of Negative Evaluation (FNE) scores (P = 0.001 and 0.020, respectively). The group differences in the scores on the other questionnaires were not significantly different. Among the PSG items, significant group differences were observed in the percentage of stage 2 non-REM sleep (N2%, P = 0.023), apnea index (AI, P = 0.005), apnea-hypopnea index (AHI, P = 0.023), and frequency of 3 % oxygen desaturation (ODI3, P = 0.001). No obesity-related parameters showed significant group differences. The percentage of days on which a PAP device was used (out of 90 days; PAP%) and percentage of days on which a PAP device was used for >4 h (Time4%) did not differ significantly. ConclusionsThe SADS, FNE, AI, AHI, N2%, and ODI3 parameters differed significantly between the EDS improvement and non-improvement groups. These parameters may help clinicians treat and predict the prognosis of patients suffering with EDS.

Association of Obstructive Sleep Apnea Syndrome (OSA/OSAHS) with Coronary Atherosclerosis Risk: Systematic Review and Meta-Analysis.

Objective Obstructive sleep apnea syndrome (OSA) is the most common type of sleep disorders. This study aimed to systematically review the correlation between OSA and the risk of coronary atherosclerosis. Methods Literature on case-control studies on the relationship between coronary heart disease (CHD) and sleep apnea syndrome was collected and collated, and the incidence of SAS in CHD and non-CHD patients was observed and compared. RevMan 5.2 analysis software and Stata12SE analysis software were used for heterogeneity test and combination analysis of the included studies. The results were expressed with odds ratio (OR), 95% confidence intervals (CI) were calculated, and publication bias and sensitivity tests were evaluated. Results There was a statistical difference in OSA associated with the risk of coronary atherosclerosis between the experimental group and the control group [OR = 1.38, 95% CI (1.18, 1.62), P < 0.0001, I2 = 0%, Z = 3.93]. OSA associated with vascular endothelial injury [OR = 3.59, 95% CI (3.00, 4.29), P < 0.00001, I2 = 90%, Z = 14.09]. OSA is associated with vascular oxidation emergency [OR = 2.19, 95% CI (2.05, 2.33), P < 0.00001, I2 = 94%, Z = 23.40]; OSA is associated with chronic vascular inflammation [OR = 1.70, 95% CI (1.39, 2.07), P < 0.00001, I2 = 16%, Z = 5.18]. Conclusion The incidence of obstructive sleep apnea in patients with CHD was higher than that in non-CHD patients, and obstructive sleep apnea was a risk factor for CHD.

Prevalence of elevated hemoglobin and hematocrit levels in patients with obstructive sleep apnea and the impact of treatment with continuous positive airway pressure: a meta-analysis

ABSTRACT Objectives Obstructive sleep apnea (OSA) is reported to be a cause of secondary polycythemia. The present study (i) reviewed the literature reporting the prevalence of secondary polycythemia in patients with OSA and (ii) determined the effect of continuous positive airway pressure (CPAP) therapy on hemoglobin and hematocrit levels in patients with OSA. Methods We searched MEDLINE, Embase and Cochrane for studies of adult patients with OSA that reported hemoglobin and/or hematocrit levels. We performed summary estimates of (i) polycythemia prevalence and a subgroup analysis according to OSA severity, and (ii) change in hemoglobin and hematocrit levels following treatment with CPAP. Results Synthesis of seven studies including 3,654 patients revealed an overall polycythemia prevalence of 2% (95% CI 1–4%); 2% (95% CI 1–3%) in mild-to moderate and 6 % (95% CI 3–12%) in severe OSA. In the pooled analysis of ten single-arm trials including 434 patients, CPAP treatment reduced hemoglobin by 3.76 g/L (95% CI −4.73 to −2.80 g/L). Similarly, pooled analysis of ten single-arm trials including 356 patients without baseline polycythemia showed that CPAP treatment reduced hematocrit by 1.1% (95% CI −1.4 to −0.9%). Conclusion Our pooled analysis supports an increased prevalence of secondary polycythemia in OSA. This estimated prevalence is likely underestimated due to the change in the polycythemia diagnostic criteria in 2016. Future randomized controlled trials are needed to evaluate the effect of CPAP in patients with baseline polycythemia. HIGHLIGHTS Pooled analysis shows OSA is associated with an increased prevalence of secondary polycythemia Prevalence of polycythemia is greater in severe OSA CPAP treatment for OSA reduces both the hemoglobin and hematocrit

A Study on the Effects of Mucous Membrane of the Sinus by Severity of Sleep Breathing Disorder

Background and Objectives Obstructive sleep apnea (OSA) is an obstructive airflow disorder that occurs in the upper respiratory tract during sleep and is therefore associated with the occurrence of cardiovascular diseases. By examining the Lund-Mackay (L-M) scores and maxillary sinus mucosal conditions according to the severity of sleep breathing disorder (SBD), we tried to find out the association between SBD and sinus mucosal change.Subjects and Method Of the 189 patients who underwent sinus CT with a polysomnography test, 175 patients were enrolled in our study. We investigated the average L-M score and L-M score of five or higher, and the ratio of maxillary sinus mucosal thickness (MSMT) of 2 mm or higher.Results The average L-M score of study population was 0.98 points and the L-M score of five or more was found in 14 patients (8%). The MSMT of 2 mm or more was found in 25.5% of the study group. The average L-M scores for the different groups, namely, the simple snoring group, the mild OSA, the moderate OSA, and the severe OSA were 1.31 points, 0.77 points, 0.91 points, and 1.08 points, respectively. There was no significant difference (&lt;i&gt;p&lt;/i&gt;=0.736) among them, and there was no correlation between the apnea-hypopnea index score and the L-M score (r=-0.052, &lt;i&gt;p&lt;/i&gt;=0.499). There was no significant difference between OSA severity and MSMT (&lt;i&gt;p&lt;/i&gt;=0.490).Conclusion There was no significant difference between the L-M score and MSMT depending on the severity of SBD. Therefore, it is believed that SBD will have little effect on the sinus mucosa.

Widespread aberrant functional connectivity throughout the whole brain in obstructive sleep apnea.

ObjectiveObstructive sleep apnea (OSA) is a sleep-related breathing disorder with high prevalence and is associated with cognitive impairment. Previous neuroimaging studies have reported abnormal brain functional connectivity (FC) in patients with OSA that might contribute to their neurocognitive impairments. However, it is unclear whether patients with OSA have a characteristic pattern of FC changes that can serve as a neuroimaging biomarker for identifying OSA.MethodsA total of 21 patients with OSA and 21 healthy controls (HCs) were included in this study and scanned using resting-state functional magnetic resonance imaging (fMRI). The automated anatomical labeling (AAL) atlas was used to divide the cerebrum into 90 regions, and FC between each pair of regions was calculated. Univariate analyses were then performed to detect abnormal FCs in patients with OSA compared with controls, and multivariate pattern analyses (MVPAs) were applied to classify between patients with OSA and controls.ResultsThe univariate comparisons did not detect any significantly altered FC. However, the MVPA showed a successful classification between patients with OSA and controls with an accuracy of 83.33% (p = 0.0001). Furthermore, the selected FCs were associated with nearly all brain regions and widely distributed in the whole brain, both within and between, many resting-state functional networks. Among these selected FCs, 3 were significantly correlated with the apnea-hypopnea index (AHI) and 2 were significantly correlated with the percentage of time with the saturation of oxygen (SaO2) below 90% of the total sleep time (%TST < 90%).ConclusionThere existed widespread abnormal FCs in the whole brain in patients with OSA. This aberrant FC pattern has the potential to serve as a neurological biomarker of OSA, highlighting its importance for understanding the complex neural mechanism underlying OSA and its cognitive impairment.

Temporal changes in coronary artery function and flow velocity reserve in mice exposed to chronic intermittent hypoxia.

Obstructive sleep apnea (OSA) is a chronic condition characterized by intermittent hypoxia (IH) that is implicated in an increased risk of cardiovascular disease (i.e., coronary heart disease, CHD) and associated with increased overall and cardiac-specific mortality. Accordingly, we tested the hypothesis that experimental IH progressively impairs coronary vascular function and in vivo coronary flow reserve. Male C57BL/6J mice (8-week-old) were exposed to IH (FiO2 21% 90 s-6% 90 s) or room air (RA; 21%) 12 h/day during the light cycle for 2, 6, 16, and 28 weeks. Coronary artery flow velocity reserve (CFVR) was measured at each time point using a Doppler system. After euthanasia, coronary arteries were micro-dissected and mounted on wire myograph to assess reactivity to acetylcholine (ACh) and sodium nitroprusside (SNP). Endothelium-dependent coronary relaxation to ACh was preserved after 2 weeks of IH (80.6 ± 7.8%) compared to RA (87.8 ± 7.8%, p = 0.23), but was significantly impaired after 6 weeks of IH (58.7 ± 16.2%, p = 0.02). Compared to ACh responses at 6 weeks, endothelial dysfunction was more pronounced in mice exposed to 16 weeks (48.2 ± 5.3%) but did not worsen following 28 weeks of IH (44.8 ± 11.6%). A 2-week normoxic recovery after a 6-week IH exposure reversed the ACh abnormalities. CFVR was significantly reduced after 6 (p = 0.0006) and 28 weeks (p < 0.0001) of IH when compared to controls. Chronic IH emulating the hypoxia-re-oxygenation cycles of moderate-to-severe OSA promotes coronary artery endothelial dysfunction and CFVR reductions in mice, which progressively worsen until reaching asymptote between 16 and 28 weeks. Normoxic recovery after 6 weeks exposure reverses the vascular abnormalities.

Impaired Glymphatic System Actions in Obstructive Sleep Apnea Adults.

Study ObjectivesObstructive sleep apnea (OSA) is accompanied by sleep fragmentation and altered sleep architecture, which can potentially hinder the glymphatic system, increasing risks for Alzheimer’s disease (AD), but the status is unclear in OSA. Our aim was to investigate the glymphatic system in OSA subjects and examine the relationships between OSA disease severity, sleep symptoms, and glymphatic system indices in OSA using diffusion tensor imaging (DTI).MethodsWe acquired DTI data from 59 OSA and 62 controls using a 3.0-Tesla MRI and examined OSA disease severity and sleep symptoms with the Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). Diffusivity maps in the x-axis (Dxx), y-axis (Dyy), and z-axis (Dzz), as well as in x-y axis (Dxy), y-z axis (Dyz), and x-z axis (Dxz) were calculated, diffusion values for the projection and association fibers extracted, and the DTI analyses along the perivascular space (DTI-ALPS index) were performed. The glymphatic system indices were compared between groups and correlated with disease severity and sleep symptoms in OSA subjects.ResultsDzz values, derived from projection fiber areas, Dyy and Dzz values from association fiber areas, as well as ALPS and Dyzmean values were significantly reduced in OSA over controls. Significant correlations emerged between disease severity, sleep symptoms, and Dxy, Dxx, and Dzz values in OSA subjects.ConclusionOSA patients show abnormal glymphatic system function that may contribute to increased risks for AD. The findings suggest that the APLS method can be used to assess the glymphatic system in OSA patients.

Impact of moderate-to-severe obstructive sleep apnea on aggressive clinicopathological features of papillary thyroid carcinoma

ObjectiveObstructive sleep apnea (OSA) may to be strongly associated with cancer mortality. The risk hazards of OSA regarding aggressive features of papillary thyroid carcinoma (PTC) remain unclear. The main objective of this study was to explore the relationship between OSA and aggressive features of PTC. MethodsWe prospectively studied 210 patients (54 men, 156 women; age 43 ± 13 years) with PTC. Indices of sleep respiratory disturbance and oxygen desaturation were determined by polysomnography with the apnea-hypopnea index (AHI) and lowest oxygen saturation (LSaO2), respectively. PTC aggressive features were assessed by postoperative histopathological analysis. Multivariant logistic regression models adjusting for demographic and OSA-related factors were generated to determine OSA risk hazards for aggressive PTC features. ResultsThe prevalence of moderate-to-severe OSA (defined as AHI of >15) was 20% in PTC patients. Those in the moderate-to-severe OSA group had higher BMI and more aggressive PTC features. Moderate-to-severe OSA was associated with increased odds of larger tumor size (OR, 4.31; 95% CI, 1.79–10.37; p = 0.001), capsular invasion (OR, 2.96; 95% CI, 1.42–6.16; p = 0.004), multifocality (OR, 3.11; 95% CI, 1.52–6.39; p = 0.002), central (OR, 4.7; 95% CI, 1.77–12.49; p = 0.003) and lateral (OR, 5.94; 95% CI, 2.27–15.54; p < 0.001) cervical lymph node metastasis, and BRAF mutation (OR, 2.88; 95% CI, 1.31–6.31; p = 0.008). Moderate to severe hypoxemia did not correlated with aggressive PTC behaviors. ConclusionsOSA is a common respiratory disturbance in PTC. Aggressive PTC features in patients with moderate-to-severe OSA implicate OSA as a cause of cancer progression. Respiratory disturbance events have a greater impact on PTC aggressiveness than hypoxia.

Circadian Rhythm of Salivary Cortisol in Obese Adolescents With and Without Apnea: A Pilot Study.

Background and ObjectiveObstructive sleep apnea (OSA) and obesity are associated with stress system activation involving the hypothalamic-pituitary-adrenal (HPA) axis in adults, but these effects in childhood and adolescence remain unclear. We examined diurnal salivary cortisol as a measurement of the HPA axis function in obese adolescents with and without OSA and the relationships between cortisol levels, body weight, and parameters of polysomnography (PSG).MethodsAfter PSG, saliva samples were collected from obese participants (with and without OSA) and lean participants four times over a 24-h period, namely, at 7:00 h (m-sCort), 13:00 h (a-sCort), 19:00 h (e-sCort), and 23:00 h (n-sCort). An enzyme-linked immunosorbent assay (ELISA) was used to measure salivary cortisol levels. The mean values of cortisol levels and fixed-time point diurnal cortisol slope (DCS) were calculated and compared among the three study groups. Correlations between parameters were analyzed using Spearman's correlation coefficients.ResultsObese OSA participants had significantly higher e-sCort and n-sCort levels than both obese non-OSA participants and lean controls. However, m-sCort and a-sCort in these patients had a pronounced upward trend. M-sCort was significantly correlated with both the lowest oxygen saturation (SpO2) and time with SpO2 <90%. Moreover, in the obese OSA group, DCS was significantly flatter than in the other two groups. The a-sCort in obese non-OSA participants was significantly higher than that in the lean control group and, surprisingly, was positively correlated with the apnea/hypopnea index. Additionally, m-sCort was related to body weight.ConclusionThis study provided further evidence for alterations in diurnal cortisol production in obese adolescents, which may indicate a chronically stressed HPA axis. However, there were significant differences in salivary cortisol parameters between participants with and without OSA. Furthermore, patients with OSA had more associations between time-point cortisol levels and OSA-related indices. Nonetheless, this research is a pilot study, and further investigations are necessary.

Association of insomnia and short sleep duration, alone or with comorbid obstructive sleep apnea, and the risk of chronic kidney disease.

Obstructive sleep apnea (OSA), sleep fragmentation, and short sleep duration (SD) have been associated with chronic kidney disease (CKD). However, these potential mechanisms for CKD have not been compared in the same cohort. This study investigated the independent and combined impact of OSA and insomnia with short sleep duration on the risk of CKD progression in a sleep clinic population. In a cross-sectional study design, adults with suspected OSA completed an overnight sleep study and a questionnaire that included the Insomnia Severity Index (ISI) and Pittsburgh Sleep Quality Index (PSQI). They also provided blood and urine samples for measurement of the glomerular filtration rate and urine albumin:creatinine ratio, from which the risk of CKD progression was determined. Participants (n = 732, 41% female, 55 ± 13 years) were categorized into four groups: no/mild OSA without insomnia (NM-OSA, n = 203), insomnia with SD without OSA (Insomnia-SD, n = 104), moderate-to-severe OSA without insomnia (MS-OSA, n = 242), and comorbid insomnia and OSA with SD (COMISA-SD, n = 183). After stratification, 12.8% of NM-OSA, 15.4% of Insomnia-SD, 28.9% of MS-OSA, and 31.7% of the COMISA-SD participants had an increased risk of CKD progression. Compared to NM-OSA, the odds ratio (OR) for an increased risk of CKD progression was not increased in Insomnia-SD (OR 0.95, confidence interval [CI]: 0.45-1.99) and was increased to the same degree in MS-OSA (OR 2.79, CI: 1.60-4.85) and COMISA-SD (OR 3.04, CI: 1.69-5.47). However, the ORs were similar between the MS-OSA and COMISA-SD groups across all statistical models (p ≥ .883). In a sleep clinic population, insomnia with short sleep duration does not increase the risk of CKD progression; nor does it further increase the risk of CKD progression associated with moderate-to-severe OSA.

Obstructive sleep apnoea and left ventricular diastolic dysfunction among first responders to the 9/11 World Trade Center terrorist attack: a cross-sectional study

ObjectivesObstructive sleep apnoea (OSA) is often linked to cardiovascular disease. A limited number of studies have reported an association between OSA and left ventricular diastolic dysfunction (LVDD). However, prior studies...

Obstructive Sleep Apnea Effects on Pulmonary and Respiratory Muscle Function of Obese Children and Adolescents: A Preliminary Study.

OBJECTIVEObstructive sleep apnea causes a marked decrease in lung volume and increases lung elasticity in obese adults. However, pulmonary and respiratory muscle function of obese children with obstructive sleep apnea who are more prone to develop airway obstruction than adults is less understood. This study aimed to determine the effects of obstructive sleep apnea on pulmonary and respiratory muscle function in obese children and adolescents compared to those without obstructive sleep apnea.MATERIAL AND METHODSThis cross-sectional study enrolled 12 obese children and adolescents with a known polysomnographic diagnosis of obstructive sleep apnea and 12 controls that were matched for age, gender, and body mass index. Pulmonary function, maximal inspiratory pressure, maximum voluntary ventilation, and anthropometric variables were measured.RESULTSObese children and adolescents with obstructive sleep apnea exhibited significantly lower maximal mid-expiratory flow and displayed a forced expiratory flow at 50% and 75% of vital capacity (all P< .05) compared to the control group. However, there were no changes in other pulmonary function variables (all P > .05). Their maximal inspiratory pressure and maximum voluntary ventilation were lower than those of the controls, but this was not statistically significant (all P> .05).CONCLUSIONObstructive sleep apnea did not change pulmonary and respiratory muscle function in obese children and adolescents. The special assessment should be warranted to identify a reduction in maximal mid-expiratory flow and forced expiratory flow at 50% and 75% of vital capacity observed in this population.

The Effects of CPAP Treatment on Resting-State Network Centrality in Obstructive Sleep Apnea Patients.

Background and ObjectivesObstructive sleep apnea (OSA) is the most common sleep disorder and previous studies have shown that OSA patients suffer from brain network impairments associated with cognitive deficits, and continuous positive airway pressure (CPAP) treatment can improve clinical symptoms. However, the relationship between CPAP treatment and brain network changes remains unclear. This study explored the characteristics of brain network changes in OSA patients before (pre-CPAP) and after one month of CPAP treatment (post-CPAP).MethodsWe collected data, including sleep monitoring, clinical assessment, and magnetic resonance imaging scans, from 21 OSA patients and 21 age-matched healthy controls (HCs). Voxel-level degree centrality (DC) was used to assess whole-brain network connectivity characteristics, a two-sample t-test was used to compare network differences between pre-CPAP OSA patients and HCs, and a paired sample t-test was used to compare the characteristics of brain network changes in OSA patients before and after treatment. The correlations between the DC value and each of the clinical variables were analyzed in the OSA patients.ResultsCompared with HCs, pre-CPAP OSA patients showed increased DC values in the bilateral cerebellar posterior lobes (CPLs) and decreased DC values in the right superior temporal gyrus, left superior frontal gyrus and right middle frontal gyrus. Compared with pre-CPAP OSA patients, post-CPAP OSA patients showed reduced DC values in the bilateral CPL and increased DC values in several brain regions in the frontal, temporal, and insular lobes after CPAP treatment. The Montreal Cognitive Assessment MoCA (MoCA) scores were positively correlated with the DC value of the bilateral cerebellum posterior lobe, right middle temporal gyrus, left superior temporal gyrus, left paracentral lobule and left paracentral lobule. Also, Pittsburgh Sleep Quality Index (PSQI) scores were negatively correlated with the DC value of the right middle temporal gyrus in post-CPAP OSA patients.ConclusionCPAP treatment can effectively reverse the compensatory response of the bilateral CPL and functional network damage brought about by OSA, which may provide potential neuroimaging biomarkers for CPAP treatment evaluation.

Obstructive sleep apnea is associated with cognitive impairment in minor ischemic stroke

ObjectivesObstructive sleep apnea (OSA) is commonly seen in stroke patients, and its relationship with cognitive impairment remains poorly understood. This study aimed to explore the roles of OSA in cognition impairment in patients with minor ischemic stroke.MethodsPatients with minor ischemic stroke were consecutively enrolled from January 2020 to May 2021. Every patient underwent polysomnography (PSG) to assess for OSA. Based on the apnea hypopnea index (AHI), patients were grouped into the no OSA (AHI < 5), mild OSA (5 ≤ AHI < 15), and moderate-to-severe OSA (MS OSA, AHI ≥ 15) groups. Neuropsychological assessments were performed to evaluate cognitive function, and the correlations between cognitive function and OSA were investigated.ResultsOf 94 patients, 35 had no OSA, 32 had mild OSA, and 27 had moderate-to-severe OSA. Compared to the no or mild OSA groups, the moderate-to-severe OSA group performed worse on the Chinese version of the Auditory Verbal Learning Test (CAVLT)-Recognition (p < 0.001), Digital Span Test (DST)-Backward (p < 0.001), Montreal Cognitive Assessment (MoCA) (p < 0.001), and Stroop Color and Word Test (SCWT)-Interference (p < 0.001). The severity of cognitive impairment was assessed using the MoCA, which was negatively related to the AHI (p = 0.041) and lowest SpO2 (p = 0.048).ConclusionsThe findings suggest that OSA has significant effects on cognition impairment in patients with minor ischemic stroke and that hypoxemia may be a potential pathophysiological mechanism of OSA-induced cognitive impairment.

Chronic intermittent hypoxia induces gut microbial dysbiosis and infers metabolic dysfunction in mice

Background and objectivesObstructive sleep apnea (OSA) is a highly prevalent sleep disorder, and has been associated with adverse metabolic outcomes. There is increasing evidence indicating the important role of gut microbiota in OSA and its comorbidities, while the perturbation of intestinal microbial community elicited by OSA has yet to be well-characterized. Here, we investigated the effect of chronic intermittent hypoxia (IH), a hallmark feature of OSA, on gut microbiota in mice. MethodsMale C57BL/6 mice were exposed to a pattern of chronic IH or normoxic conditions for 6 weeks. Fecal samples were collected. The composition of microbiota was determined by 16S rRNA gene amplicon sequencing, and PICRUSt2 was performed to predict functional potential of gut microbiome. ResultsIn IH mice, accompanied with elevated systemic inflammation, gut microbiota were significantly altered, characterized by enriched Bacteroides, Desulfovibrionaceae and decreased Bifidobacterium. Bacterial operational taxonomic units (OTUs) were clustered into co-abundance groups (CAGs) as potential functional unit in response to IH exposure. One CAG including bacteria of Bacteroides acidifaciens and Desulfovibrionaceae was positively correlated with systemic inflammation in mice, while another CAG composed of bacteria in Muribaculaceae was negatively correlated. Prediction of metabolic pathways showed that, changes in microbiota from IH treatment mainly impacted on bile acid and fatty acid metabolism. ConclusionOur data demonstrated that dysbiosis of gut microbiome was associated with systemic inflammation and metabolism disorder, and emerges as a mediator for IH and its consequences. Targeting microbiota will be a promising approach to curtail metabolic risks of OSA clinically.

Preoperative oximetry-derived hypoxemia predicts postoperative cardiovascular events in surgical patients with unrecognized obstructive sleep apnea

Study objectiveObstructive sleep apnea (OSA) is known to be associated with postoperative cardiovascular events in patients undergoing major non-cardiac surgery. The objective of the study is to determine whether preoperative oximetry-derived hypoxemia predicts postoperative cardiovascular events in surgical patients with unrecognized obstructive sleep apnea. Design and settingThe study was a planned post hoc analyses of a multicenter prospective cohort study. PatientsThe inclusion criteria were patients ≥45 years old undergoing major non-cardiac surgery with cardiovascular risk factors. Interventions and measurementsAll patients underwent pre-operative pulse oximetry (PULSOX-300i, Konica-Minolta Sensing, Inc). The severity of OSA was classified based on oxygen desaturation index (ODI) (mild: ≥5 to <15, moderate: ≥15 to <30, and severe OSA: ≥30 events/h). The 30 days cardiovascular events were a composite of myocardial injury, cardiac death, congestive heart failure, thromboembolism, atrial fibrillation, and stroke. Main resultsFor 1218 patients with mild, moderate, or severe OSA (mean age: 67.2 ± 9.3 years; body mass index: 27.0 ± 5.3 kg/m2), the rate of postoperative cardiovascular events was 16.4%, 25.2%, and 29.8% respectively. The multivariable analysis showed that preoperative oxygen desaturation index (ODI) ≥30 events per hour {adjusted hazard ratio (aHR) 1.63 [95% confidence interval (CI): 1.05–2.53]}, and cumulative time spent during sleep with oxygen saturation below 80% (CT80) ≥10 min {aHR 1.79 [95% CI: 1.28–2.50]} were independent predictors of 30-day postoperative cardiovascular events. ConclusionsPreoperative ODI ≥30 events per hour and CT80 ≥ 10 min are associated with increased risk of postoperative cardiovascular events. Preoperative screening using oximetry helps in risk stratification for unrecognized sleep apnea.Clinical Trial Registration:ClinicalTrials.gov Identifier: NCT01494181

Inflammatory markers and BDNF in obstructive sleep apnea (OSA) in Parkinson's disease (PD)

ObjectiveObstructive sleep apnea (OSA) exacerbates Parkinson's disease (PD) manifestations including cognitive dysfunction. Both OSA and PD have been associated with inflammation. Brain-derived neurotrophic factor (BDNF) has been implicated in cognitive function. We aimed to investigate inflammatory cytokines and BDNF in relation to OSA and PD symptoms. MethodsIn a prospective observational study, patients with PD underwent overnight polysomnography. Morning serum levels of interleukin (IL)-1β, IL-6, IL-8, TNFα, and BDNF were quantified at baseline (n = 64) and 6 months (n = 38). Outcomes included non-motor and motor standard scores; Montreal Cognitive Assessment (MoCA); and Epworth Sleepiness scale (ESS). Associations were assessed using linear regression, adjusting for age, sex and body mass index. ResultsAt baseline, IL-6 was associated with the Apnea–Hypopnea Index (β = 0.013, p = 0.03), and the Oxygen Desaturation Index (β = 0.028, p = 0.002). No other associations between cytokines and sleep parameters were found. Motor dysfunction was associated with IL-6 (β = 0.03, p = 0.001). ESS was associated non-significantly with IL-6 (β = 0.04, p = 0.07) and BDNF (β = 555, p = 0.06). At follow-up, change in IL-6 was associated with change in non-motor (β = 0.08, p = 0.007), and motor (β = 0.03, p = 0.001) symptoms. Change in BDNF was associated with change in ESS (β = 1450, p = 0.02). InterpretationWe found an association between IL-6 levels and both OSA severity and PD motor dysfunction. At follow-up, increasing IL-6 correlated with deterioration of motor and non-motor PD symptoms. Increasing BDNF correlated with increasing sleepiness. Further work with a larger sample size is needed, but our results support the hypothesis that OSA-related inflammation plays a role in PD manifestations and progression.

The impact of the Adenotonsillectomy on cardiac functions and oxidative stress

ObjectiveObstructive sleep apnea syndrome (OSAS) causes cardiovascular comorbidities and increased oxidative stress. Adenotonsillectomy is the first treatment option for OSAS secondary to adenotonsillar hypertrophy (ATH). This study evaluated the presence of cardiovascular changes, hypertension and oxidative stress before and after adenotonsillectomy in patients with OSAS secondary to ATH. MethodsPatients with ATH diagnosed with OSAS by polysomnography (PSG) were included. All participants received an Echocardiography (ECHO) and 24-h ambulatory blood pressure measurement (ABPM). Serum malonyldialdehyde (MDA) and total oxidant activity (TOS) levels of oxidant parameters; total antioxidant activity (TAS), catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH) levels of antioxidant parameters were measured. All patients received an adenotonsillectomy. Postoperative evaluation was performed at the 6th month. In the postoperative period, PSG, ECHO, ABPM and the oxidant-antioxidant parameter levels in the serum was repeated. ResultsTwenty-eight patients (13 males, 15 females; mean age 8.2 ± 2.06 years) were included in the study. In the preoperative period, concentric remodeling was observed in 14,8% of the patients, although they had no cardiovascular system complaints. The apnea-hypopnea index (AHI) scores were classified as mild in 39.3% (n = 11), moderate in 21.4% (n = 6) and severe in 39.3% (n = 11) preoperatively. In the postoperative period, 22 patients were evaluated. It was observed that the severity of OSAS decreased, ventricular functions improved, oxidant parameters decreased and antioxidant parameters increased postoperatively. ConclusionAdenotonsillectomy provides a positive change in cardiovascular system parameters and an antioxidant change in the oxidative balance in patients with OSAS.

Risk of obstructive sleep apnea among taxi-motorbike drivers in Parakou city in West Africa and associated factors with road traffic accidents.

ObjectivesObstructive sleep apnea (OSA) is an underdiagnosed chronic respiratory disease, causing excessive daytime sleepiness (EDS) and road traffic accidents (RTA). This study aimed to determine the risk of OSA among taxi–motorbike drivers (TMD) and factors associated with RTA in Parakou, Benin.MethodsA cross-sectional comparative study was carried out between July and September 2020, including 225 TMD and 450 motorbike drivers other than TMD (non-TMD). A multiple logistic regression was then performed to determine factors associated with RTA.ResultsThe mean age of participants was 38.2 ± 10.2 and 36.6 ±10.9 years, respectively, for TMD and non-TMD (p = .048). The average daily working time was 10.7 ± 2.3H and 9.1±3.5H, respectively, for TMD and non-TMD (p < .001). Average sleeping time was comparable in both groups (7.5±1.4H vs 7.4±1.4H; p = .415). TMD significantly more complained of non-restorative sleep (38.7% vs 18.4%; p < .001) but less of EDS (20.0% vs 28.7%; p = .015). Abdominal obesity predominated in TMD (13.8% vs 4.4%; p < .001). An increased risk of OSA (NoSAS score ≥8) was diagnosed in 25.8% TMD and 26.7% non-TMD (p = .805). Overall, 25.8% of TMD and 18.4% of non-TMD (p = .027) reported at least one RTA in the last 12 months. After adjusted analysis, the unique factor associated with RTA was a daily sleeping pills consumption (aOR=2.2; 95%CI = 1.2–3.8; p = .006).ConclusionThere is need to improve systematic screening and diagnosis of OSA in both TMD and non-TMD and reinforce the regulation and consumption of sleeping pills.

Evaluation Parameter of Excessive Daytime Sleepiness for Obstructive Sleep Apnea Patients

Background and Objective Obstructive sleep apnea (OSA) is a sleep-related breathing disorder caused by repetitive obstruction of the upper airway. Repetitive obstruction of the upper airway causes impaired gaseous exchange, resulting hypoxia, hypercapnia, and frequent arousals of sleep architecture. Polysomnography (PSG) is a gold standard for diagnosing OSA. Excessive daytime sleepiness (EDS) is a common accompanying daytime symptoms in OSA patients. Since EDS can cause unexpected events such as traffic accident or poor performance in workplace, it is regarded as a significant public health problem. Therefore, accurate assessment and prediction of this symptom is important. The Epworth Sleepiness Scale (ESS) and multiple sleep latency test are most commonly used to evaluate EDS, but their efficacies are controversial. The purpose of this study is to find the parameter to evaluate and predict the EDS for OSA patients.Methods We retrospectively reviewed the medical records of 88 OSA patients. Patients were divided into two groups according to the presence of EDS. We analyzed the clinical records, questionnaire scores, and PSG data to find the difference between two groups.Results ESS was 10.64 ± 4.28 in EDS patients and 8.63 ± 4.86 in non-EDS patients. ESS showed a statistically significant difference between two groups (p = 0.044). Also, the percentage of 1st stage non-REM sleep in total sleep time (N1%) was 25.09 ± 15.24 in EDS patients and 18.97 ± 10.30 in non-EDS patients and showed a statistically significant difference between groups (p = 0.033). Patients’ weight was 81.59 ± 20.52 in EDS patients and 74.14 ± 12.63 in non-EDS patients and showed a statistically significant difference between groups (p = 0.046).Conclusions ESS, N1% and patients’ weight were significant parameter which is related with the presence of EDS for OSA patients. These parameters will be useful in evaluating the presence of EDS for OSA patients. Also, in patients diagnosed with sleep disorder with high N1%, EDS must be accurately evaluated as well.