Obstructive Sleep Apnea Syndrome Patients Research Articles

Long-term outcomes of pharyngoplasty for Obstructive Sleep Apnea Syndrome.

Introduction: Pharyngoplasty techniques for the treatment of obstructive sleep apnea syndrome (OSAS) have evolved, which improved the understanding of the anatomy, patient selection, and adoption of functional approaches. Aim: To analyze long-term results of pharyngoplasty in OSAS patients. Material and methods: Between 2007 and 2021, a total of 234 adult patients with OSAS who had previously failed positive airway pressure (PAP) therapy underwent sleep surgery. Of this group, 75 patients met the criteria of a minimum 5-year follow-up. To date, 25 patients completed the follow-up study protocol, including the medical history, visual analog scale (VAS) for snoring loudness, body mass index (BMI), endoscopy of the upper airways, type III sleep study, and standardized questionnaires including Epworth Sleepiness Scale (ESS) and EQ-5D-5L Euro - Quality of Life Questionnaire. Results: The average period of follow-up was 96.80 ± 30.20 months. The mean age of participants was 54.6 ± 14.02 and the mean BMI 30.28 ± 2.74. Patients underwent uvulopalatopharyngoplasty (n = 21) and expansion sphincterpharyngoplasty (n = 4) between 2008-2015. A long-term improvement in sleep parameters was observed for the mean AHI (29.84 ± 20.06before and 19.45 ± 18.53 after surgery, p = 0.0294), and the median VAS (8.13 before and 3.78 after surgery), mean oxygen saturation during sleep 94,5% (IQR 93.0-95.25), and the median ESS score was 6.17 ± 4.57. The majority of patients reported subjective long-term improvement in sleep quality and a reduction of snoring. Conclusions: In OSAS patients who failed PAP therapy, pharyngoplasty may provide a long-term improvement in upper airway obstruction during sleep.

Use of eustachian tube dysfunction questionnaire in obstructive sleep apnea syndrome

OBJECTIVE: This study aimed to investigate the eustachian tube dysfunction (ETD) of patients with obstructive sleep apnea syndrome (OSAS) using the Eustachian Tube Dysfunction Questionnaire-7 (ETDQ-7). METHODS: The study included 96 patients (78 males, 18 females; mean age 39.4±12.2 years; range 18 to 64 years) diagnosed with OSAS by polysomnographic evaluation. All patients were administered the ETDQ-7. Age, sex, presence of septum deviation, Epworth Sleepiness Scale, apnea-hypopnea index (AHI), lowest oxygen saturation, and oxygen desaturation index parameters were recorded. The patients were divided into mild, moderate, and severe OSAS groups according to the AHI score. The parameters of the cases in each group were compared, and their correlation with the ETDQ-7 scores was evaluated. RESULTS: The fourth question score and the total score in the group with severe OSAS were significantly higher than the groups with mild and moderate OSAS (p<0.05 for all). The fourth question score and the total score were significantly higher in the group with moderate OSAS than the group with mild OSAS (p<0.05 for all). There was a significant positive correlation between the oxygen desaturation index and the scores of questions 1, 3, 4, 6, and 7 and the total score (p<0.05 for all). CONCLUSION: Questionnaire scores were higher in patients with severe OSAS compared to mild to moderate OSAS patients. Based on this data, we would like to emphasize that OSAS cases may develop ETD and other related pathologies.

Functional analysis of the human rib cage over the vital capacity range in standing position using biplanar X-ray imaging

Pathologies of the respiratory system can by accompanied by alterations of the biomechanical function of the rib cage, as well as of its morphology and movement. The assessment of such pathologies could benefit from rib cage kinematic analysis during breathing, but this analysis is challenging because of the difficulties in observing and quantifying bone movements in vivo. This work explored the feasibility of using biplanar x-rays to study rib cage modifications at different lung volumes and evaluated the potential of the method to characterize rib cage kinematic patterns in patients.Forty-seven asymptomatic adults and eleven obstructive sleep apnea syndrome (OSAS) patients underwent biplanar x-rays at three lung volumes: normal breathing, maximal and minimal volume. Rib cage and spinopelvic positional parameters were computed from 3D reconstruction of the skeleton.Results showed that inspiration mostly mobilized the ribs and costo-vertebral junction, while expiration was driven by the spine. OSAS patients had a different sagittal profile at rest than asymptomatic subjects, but these differences decreased at maximal and minimal volume. This suggests that patients employed different biomechanical strategies to attain a trunk configuration similar to asymptomatic subjects at minimal and maximal lung volume.This study confirmed that the proposed method could have an impact for the clinical assessment and understanding of pathologies involving breathing function, and which directly affect rib cage morphology.

Frequency of overactive bladder (OAB) and the factors affecting it in patients with obstructive sleep apnea syndrome (OSAS).

To investigate the prevalence of overactive bladder (OAB) in patients with obstructive sleep apnea syndrome (OSAS) and the factors affecting it. A total of 255 patients were included in this prospectively designed study. Among all patients, 166 were male, 89 were female; 213 patients were married and 42 were single. All patients underwent polysomnography. All patients completed the OAB-V8 form. OSAS was diagnosed via polysomnography. OAB was diagnosed via OABV8. The participants were evaluated as patients with and without OAB and those with and without OSAS. SPSS for Windows version 18.0 software was used for the statistical analysis and the level of significance was set at α = 0.05. The prevalence of OAB was high among the OSAS patients (66.3%, n = 136). Age, body mass index, waist circumference, marital status, oxygen desaturation index (ODI4) ⩾4%, apneahypopnea index (AHI), the number and duration of decreases in O2 saturation below 90%, wake after sleep onset (WASO) duration, and groups, and OSAS severity were different in the OAB group (p < 0.05). Duration and number of O2 saturation <90%, and ODI4 are higher in the OSAS group and OAB group (p < 0.05). In multivariate logistic regression analysis, AHI, WASO, age, and marital status were the factors influencing OAB. OAB is seen at a high rate in OSAS patients. Hypoxia is the main basis for both diseases and probably it is the common pathway. AHI, WASO, age, and marital status can provide valuable information to physicians for predicting OAB.

Evaluation of the effect of obstructive sleep apnea syndrome on retinal microvascularity by optical coherence tomography angiography

PurposeUsing optical coherence tomography angiography (OCTA), we sought to determine whether there are retinal microvascular changes in patients with obstructive sleep apnea syndrome (OSAS). MethodThe study included 56 patients diagnosed with OSAS by polysomnography [21 patients with mild OSAS (group 1), 14 with moderate OSAS (group 2) and 21 with severe OSAS (group 3)], and 26 healthy individuals as a control group (group 4). The vascular densities of the superficial capillary plexus and deep capillary plexus of the retinal segmentations, together with the foveal avascular zone (FAZ) width, were measured for all participants, using OCTA. ResultCompared with the control group, vascular densitiy in whole image of superficial capillary plexus were found to be significantly lower in group 2. In addition, vascular densitiy in fovea region of superficial capillary plexus was significantly lower in group 1 than the control group. In deep capillary plexus, vascular densitiy of whole image, superior hemi and nasal regions were found to be significantly lower in group 2 and group 3 compared with the control group. Parafoveal region in group 3 had significantly lower vascular densities than the controls. A significantly larger FAZ was also found in group 1 and group 3 in the deep capillary plexus, compared with the controls. ConclusionWe detected smaller vascular densities in both the superficial capillary plexus and deep capillary plexus and a larger deep capillary plexus FAZ in OSAS patients. Therefore, OCTA may be useful as a non-invasive method to understand the systemic effects of OSAS.

Obstructive Sleep Apnea Syndrome Comorbidity Phenotypes in Primary Health Care Patients in Northern Greece.

Background: Obstructive sleep apnea syndrome (OSAS) is a significant public health issue. In the general population, the prevalence varies from 10% to 50%. We aimed to phenotype comorbidities in OSAS patients referred to the primary health care (PHC) system. Methods: We enrolled 1496 patients referred to the PHC system for any respiratory- or sleep-related issue from November 2015 to September 2017. Some patients underwent polysomnography (PSG) evaluation in order to establish OSAS diagnosis. The final study population comprised 136 patients, and the Charlson comorbidity index was assessed. Categorical principal component analysis and TwoStep clustering was used to identify distinct clusters in the study population. Results: The analysis revealed three clusters: the first with moderate OSAS, obesity and a high ESS score without significant comorbidities; the second with severe OSAS, severe obesity with comorbidities and the highest ESS score; and the third with severe OSAS and obesity without comorbidities but with a high ESS score. The clusters differed in age (p < 0.005), apnea–hypopnea index, oxygen desaturation index, arousal index and respiratory and desaturation arousal index (p < 0.001). Conclusions: Predictive comorbidity models may aid the early diagnosis of patients at risk in the context of PHC and pave the way for personalized treatment.

Nocturnal blood pressure profile in obstructive sleep apnea syndrome patients without hypertension

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The Positive Airway Pressure Therapy Compliance In Mild OSAS

Introduction: This study is designed to determine the factors for predicting the PAP compliance in mild obstructive sleep apnea syndrome (OSAS) for improving the cost-effectiveness in the treatment choices of these patients.&#x0D; Method: The study group comprises 27 mild OSAS patients who underwent automatic positive airway pressure (APAP) titration between July 2016 and December 2017. Demographic, clinic and polysomnographic characteristics of the patients were retrospectively evaluated. Compliance with PAP treatment was defined as the usage of 5 nights/week and 4 hours/night at least. Data of compliant patients were statistically compared with non-compliant patients.&#x0D; Results: Most of the patients (23 patients, 85,2%) were prescribed APAP devices. Acceptable compliance at the end of the first year of therapy was achieved by 11 patients (40,2%) whereas 8 patients used PAP device 2 months at most (29,6%) The remaining 8 patients had not taken the device at all and were considered as non-adherent to PAP treatment (29,6%). The nonadherent/non-compliant group showed statistically the same demographic, clinic, and polysomnographic characteristics when compared to the compliant group. The level of maximum pressure during the titration test was lower in the compliant group (p=0,040). &#x0D; Conclusion: The sleep-related symptoms, scores of ESS or polysomnographic parameters can not be used to predict compliance for mild OSAS. The patients with mild OSAS, especially the ones who reach higher maximum pressure on titration test, must be followed up closely during the first 2 months of PAP treatment to detect nonadherence/non-compliance earlier.

The effect of positive airway pressure therapy on intraocular pressure and retina in severe obstructive apnea syndrome.

To identify and compare changes in intraocular pressure (IOP), macular, and peripapillary retinal nerve fiber layer (RNFL) thickness using optical coherence tomography (OCT) measurements before and after 3 months of positive airway pressure (PAP) therapy in patients with severe obstructive sleep apnea syndrome (OSAS). Twenty-five patients diagnosed with severe OSAS in the neurology sleep outpatient clinic were included in the study. Ophthalmologic examinations were performed at the time of diagnosis and after 3months of PAP therapy. Statistical analysis of comparisons of pre-treatment and post-treatment measurements of IOP and OCT was performed. Before the PAP therapy, the correlations between central corneal thickness (CCT), body mass index (BMI), OCT, IOP, and sleep parameters were statistically analyzed. Compared to the pre-treatment measurements at the time of diagnosis, post-treatment measurements showed insignificant decrease in IOP, significant increase in mean macular thickness and significant thinning in superior nasal RNFL. There was no correlation found between pre-treatment measurements including IOP, OCT, CCT, BMI, and sleep parameters. The effect of intermittent hypoxia and hypercapnia on the IOP and macula may be reversible in severe OSAS patients receiving 3months of PAP therapy, but the reversibility of the neurodegenerative effects of OSAS on RNFL with this treatment seems controversial. OCT can be considered to be a promising technique for monitoring disease progression under PAP therapy in patients with severe OSAS.

Impact of Exposome Factors on Epidermal Barrier Function in Patients with Obstructive Sleep Apnea Syndrome.

Exposome factors, such as sleep deprivation and diet, could affect skin barrier function. The objectives of this study are to compare skin barrier function between patients with Obstructive Sleep Apnea Syndrome (OSAS) and healthy individuals, and to evaluate the effect of other exposome factors on skin. A cross-sectional study was conducted. Patients with OSAS and healthy volunteers matched by age and sex were included. OSAS severity was assessed by the Apnea-Hypopnea Index (AHI). Validated questionnaires were used to assess diet, anxiety, depression, and psychological stress. Skin barrier function parameters including temperature, erythema, melanin, pH, transepidermal water loss (TEWL), and stratum corneum hydration (SCH) were measured on the volar forearm. A total of 86 participants were included, 56 patients with OSAS and 30 healthy volunteers. TEWL was higher in OSAS patients than in healthy individuals (8.01 vs. 8.68 g·m−2·h−1). Regarding disease severity, severe patients had higher TEWL values (9.31 vs. 8.46 vs. 7.08 g·m−2·h−1) compared to moderate and mild patients. Patients with OSAS had significantly lower sleep quality (11.89 vs. 6.47 Pittsburgh Sleep Quality Index score; p < 0.001), poor adherence to the Mediterranean Diet (8.46 vs. 9.77; p = 0.005), and significantly higher anxiety and depression levels than healthy individuals. In conclusion, patients with OSAS may have skin barrier impairment, reflected in higher TEWL values. These patients also have higher levels of anxiety, depression, stress, and a lower adherence to a Mediterranean Diet, all exposome factors that might impact on skin barrier function.

Physical Fitness Differences, Amenable to Hypoxia-Driven and Sarcopenia Pathophysiology, between Sleep Apnea and COVID-19.

Handgrip strength is an indirect indicator of physical fitness that is used in medical rehabilitation for its potential prognostic value. An increasing number of studies indicate that COVID-19 survivors experience impaired physical fitness for months following hospitalization. The aim of our study was to assess physical fitness indicator differences with another prevalent and hypoxia-driven disease, Obstructive Sleep Apnea Syndrome (OSAS). Our findings showed differences between post-COVID-19 and OSAS groups in cardiovascular responses, with post-COVID-19 patients exhibiting higher values for heart rate and in mean arterial blood pressure. Oxygen saturation (SpO2) was lower in post-COVID-19 patients during a six-minute walking test (6MWT), whereas the ΔSpO2 (the difference between the baseline to end of the 6MWT) was higher compared to OSAS patients. In patients of both groups, statistically significant correlations were detected between handgrip strength and distance during the 6MWT, anthropometric characteristics, and body composition parameters. In our study, COVID-19 survivors demonstrated a long-term reduction in muscle strength compared to OSAS patients. Lower handgrip strength has been independently associated with a prior COVID-19 hospitalization. The differences in muscle strength and oxygenation could be attributed to the abrupt onset of the disorder, which does not allow compensatory mechanisms to act effectively. Targeted rehabilitation focusing on such residual impairments may thus be indispensable within the setting of post-COVID-19 syndrome.

Explainable Computer-Aided Detection of Obstructive Sleep Apnea and Depression

Obstructive Sleep Apnea Syndrome (OSAS) and Major Depressive Disorder (MDD) are common conditions associated with poor quality of life. In this work, we aim to classify OSAS and depression in patients with OSAS using machine learning techniques. We have extracted features from electrocardiograms (ECG), electroencephalograms (EEG), and breathing signals from polysomnography (PSG) at specific 5-minute intervals, where the participants’ statuses are known, meaning we do not need breathing signals. These statuses include sleep stage, whether or not they have depression, or an apneic event has occurred. The PSGs were recorded from a total of 118 subjects with a 75/25 split for training and testing and the resultant features were used in sleep staging and classifying OSAS and depression in OSAS patients. Sleep staging was best done with random forest without feature selection, yielding an accuracy of 70.52 % and F1-Score of 69.99 %. The best classification performance of OSAS happened during deep sleep without feature selection and SVM, which yielded an accuracy of 98.36 % and F1-Score of 98.82 %. All sleep stages with Chi2 ANN yielded an accuracy of 72.95 % and F1-Score of 73.43 % for classification of depression in OSAS patients. Results show promise in detecting OSAS and depression in OSAS patients, and the Bland-Altman plot shows that posterior probability provides comparable means of detecting OSAS to the apnea-hypopnea index (AHI). Besides detection of OSAS in depressed patients, this work serves to classify depression and give insights into relevant sleep stages to both of those conditions, allowing better planning for polysomnography.

Obstructive Sleep Apnea Syndrome: The Effect of Acute and Chronic Responses of Exercise

Obstructive Sleep Apnea Syndrome (OSAS) is a sleep disorder with high prevalence in general population, but alarmingly low in clinicians' differential diagnosis. We reviewed the literature on PubMed and Scopus from June 1980–2021 in order to describe the altered systematic pathophysiologic mechanisms in OSAS patients as well as to propose an exercise program for these patients. Exercise prevents a dysregulation of both daytime and nighttime cardiovascular autonomic function, reduces body weight, halts the onset and progress of insulin resistance, while it ameliorates excessive daytime sleepiness, cognitive decline, and mood disturbances, contributing to an overall greater sleep quality and quality of life.

Evaluation of corneal, ocular surface, and meibomian gland changes in obstructive sleep apnea syndrome

To evaluate the ocular surface, eyelid changes, meibomian gland morphology, corneal endothelial morphology, and corneal topographic measurements in patients with obstructive sleep apnea syndrome (OSAS). There were 47 patients diagnosed with OSAS and 47 healthy volunteers included in the study. Non-invasive tear break-up time (NITBUT), corneal topography, meibography, and specular microscopy were performed. The mean ages of the study and control groups were 45.77±9.65 years and 44.26±8.54 years, respectively (P=0.229). The presence of floppy eye lid (17% vs. 0%; P=0.006) and lid margin abnormality score (1.09±0.8 vs. 0.21±0.51; P<0.001) were significantly different between the study and the control groups. There were insignificant differences between the groups in NITBUT and corneal topographic measurements, except for the ACT (556.96±42.4μm vs. 569±103μm, P=0.037). The mean endothelial cell density (CD) in the OSAS and control groups were 2609±259.96 and 2756±179 cells/mm2, respectively (P=0.002). Meibomian gland loss in the lower and upper eyelids was significantly higher in the OSAS group (P<0.001 for both). OSAS patients develop eyelid margin abnormalities, loss of meibomian glands, and morphological changes in the meibomian glands. A significant reduction in corneal endothelial CD indicates that systemic hypoxia in OSAS has an effect on the cornea.

Depression of Non-Neuronal Cholinergic System May Play a Role in Co-Occurrence of Subjective Daytime Sleepiness and Hypertension in Patients with Obstructive Sleep Apnea Syndrome.

PurposeSimultaneous occurrence of hypertension and excessive daytime sleepiness (EDS) is very common in obstructive sleep apnea syndrome (OSAS), although no study has specifically addressed this issue. The present study explored the risk factors for co-occurrence of OSAS-related EDS and hypertension.Patients and MethodsA total of 161 OSAS patients were studied after undergoing an eight-hour in-laboratory polysomnography for one night. The OSAS severity assessment depends on the number of breathing disturbances per hour of sleep. EDS was defined using the Epworth Sleepiness Scale (ESS) scores of ≥13. Hypertension was defined according to direct cuff blood pressure (BP) measurements. Beat-to-beat R-R interval data were incorporated in polysomnography for heart rate variability analysis. The low-frequency/high-frequency band ratio was used to reflect sympathovagal balance. The study participants were divided into four groups based on the presence of EDS and/or hypertension: EDS with hypertension (n = 53), EDS without hypertension (n = 27), no EDS with hypertension (n = 38), and no EDS or hypertension (n = 43). Clinical, polysomnographic and heart rate data were compared and studied among the four groups. Plasma acetylcholine (ACh) levels were assessed to explore the effects of the non-neuronal cholinergic system and the co-occurrence of EDS and hypertension.ResultsPatients with EDS and hypertension had more severe OSAS severity indices compared to control patients. Increased cardiac sympathovagal imbalance and nocturnal hypoxemia regulated the presence of EDS and hypertension. Further plasma biomarker analysis revealed that both ESS scores and BP levels were associated with significantly elevated plasma norepinephrine, interleukin-6 and superoxide dismutase levels and significantly decreased ACh levels. Logistic regression analyses showed that ACh was the only factor significantly associated with co-occurrence of EDS and hypertension after controlling for confounders using odds ratio of 0.932, with a 95% confidence interval of 0.868 to 1.000 (P = 0.049).ConclusionThe results suggested that OSAS coupled with both EDS and hypertension is a more severe phenotype of the respiratory disorder. The presence of EDS and hypertension was accompanied by sympathovagal imbalance, and co-occurrence of these two conditions may be related to decreased plasma ACh levels.

Predictors of changes in cerebral perfusion and oxygenation during obstructive sleep apnea

Obstructive sleep apnea syndrome (OSAS) is a common sleep disorder. Severe OSAS defined as apnea–hypopnea index (AHI) ≥ 30/h is a risk factor for developing cerebro-cardiovascular diseases. The mechanisms of how repetitive sleep apneas/hypopneas damage cerebral hemodynamics are still not well understood. In this study, changes in blood volume (BV) and oxygen saturation (StO2) in the left forehead of 29 newly diagnosed severe OSAS patients were measured by frequency-domain near-infrared spectroscopy during an incremental continuous positive airway pressure (CPAP) titration protocol together with polysomnography. The coefficients of variation of BV (CV-BV) and the decreases of StO2 (de-StO2) of more than 2000 respiratory events were predicted using linear mixed-effect models, respectively. We found that longer events and apneas rather than hypopneas induce larger changes in CV-BV and stronger cerebral desaturation. Respiratory events occurring during higher baseline StO2 before their onsets, during rapid-eye-movement sleep and those associated with higher heart rate induce smaller changes in CV-BV and de-StO2. The stepwise increased CPAP pressures can attenuate these changes. These results suggest that in severe OSAS the length and the type of respiratory event rather than widely used AHI may be better parameters to indicate the severity of cerebral hemodynamic changes.

Burden of Comorbidities in Patients with OSAS and COPD-OSAS Overlap Syndrome.

Background and Objectives: Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are usually associated with multi-morbidity. The aim of this study was to retrospectively investigate the prevalence of comorbidities in a cohort of patients with OSAS and COPD-OSAS overlap syndrome (OS) patients and to explore differences between these two groups. Materials and Methods: Included were consecutive OS patients and OSAS patients who had been referred to our sleep laboratory, and were matched in terms of sex, age, BMI, and smoking history. Presence of comorbidities was recorded based on their medical history and after clinical and laboratory examination. Results: The two groups, OS patients (n = 163, AHI > 5/h and FEV1/FVC < 0.7) and OSAS patients (n = 163, AHI > 5/h, and FEV1/FVC > 0.7), did not differ in terms of apnea hypopnea index (p = 0.346), and oxygen desaturation index (p = 0.668). Compared to OSAS patients, OS patients had lower average SpO2 (p = 0.008) and higher sleep time with oxygen saturation <90% (p = 0.002) during sleep, and lower PaO2 (p < 0.001) and higher PaCO2 (p = 0.04) in wakefulness. Arterial hypertension was the most prevalent comorbidity for both OS and OSAS, followed by dyslipidemia, cardiovascular disease (CVD) and diabetes. OS was characterized by a higher prevalence of total comorbidities (median (IQR):2 (1–3) vs. 2 (1–2), p = 0.033), which was due to the higher prevalence of CVD (p = 0.016) than OSAS. No differences were observed in other comorbidities. Conclusions: In OS patients, nocturnal hypoxia and impaired gas exchange in wakefulness are more overt, while a higher burden of CVD is observed among them in comparison to sex-, age- and BMI-matched OSAS patients.

Retinal vascular impairment in patients newly diagnosed with obstructive sleep apnea syndrome.

BackgroundTo evaluate retinal morphological and vascular parameters in patients recently diagnosed with obstructive sleep apnea syndrome (OSAS) and determine the correlation between retinal vascular density and the severity of OSAS.MethodsWe performed a retrospective study on the retinal vasculature of patients with OSAS and age-match healthy controls. OSAS was confirmed by full-night cardiorespiratory polygraphy. Patients were divided into three groups according to disease severity given by apnea-hypopnea index (AHI) i.e., mild, moderate or severe. Retinal thicknesses and vascular density were compared among groups, for both the macula and optic disc. Correlation between vascular density and clinical features were also assessed.ResultsThe study included 30 eyes of patients with OSAS and 12 controls. No differences were found regarding retinal thickness in both the macula and the optic disc between OSAS patients and controls. In contrast, significant differences were found in the peripapillary vessel density between groups versus control patients. The greatest difference being between severe OSAS and controls (49.4% ± 2.1 versus 40.4% ± 4.2 respectively, p=0.01). Peripapillary vessel density was found to significantly and negatively correlate with AHI (p=0.02; r= -0.74) and directly correlate with the lowest percutaneous oxygen saturation (p=0.02; r= 0.58).ConclusionsThis study indicates that OSAS is associated with retinal microvasculature impairment, that seems to mainly affect the optic disc. This suggests that microvascular damage increases with the increasing severity of OSAS. As such, prospective trials are needed to clarify if this vascular peripapillary damage precedes glaucomatous optic neuropathy in OSAS patients.

The Effect of Sera from Children with Obstructive Sleep Apnea Syndrome (OSAS) on Human Cardiomyocytes Differentiated from Human Embryonic Stem Cells.

Obstructive sleep apnea syndrome (OSAS) patients suffer from cardiovascular morbidity, which is the leading cause of death in this disease. Based on our previous work with transformed cell lines and primary rat cardiomyocytes, we determined that upon incubation with sera from pediatric OSAS patients, the cell’s morphology changes, NF-κB pathway is activated, and their beating rate and viability decreases. These results suggest an important link between OSAS, systemic inflammatory signals and end-organ cardiovascular diseases. In this work, we confirmed and expanded these observations on a new in vitro system of beating human cardiomyocytes (CM) differentiated from human embryonic stem cells (hES). Our results show that incubation with pediatric OSAS sera, in contrast to sera from healthy children, induces over-expression of NF-κB p50 and p65 subunits, marked reduction in CMs beating rate, contraction amplitude and a strong reduction in intracellular calcium signal. The use of human CM cells derived from embryonic stem cells has not been previously reported in OSAS research. The results further support the hypothesis that NF-κB dependent inflammatory pathways play an important role in the evolution of cardiovascular morbidity in OSAS. This study uncovers a new model to investigate molecular and functional aspects of cardiovascular pathology in OSAS.

Association between Interleukin-6 and vitamin D serum levels in patients with obstructive sleep apnea syndrome and impact of long-term continuous positive airway pressure therapy on biomarker levels

ObjectiveHypoxia induces interleukin-6 (IL-6) production in obstructive sleep apnea syndrome (OSAS). Low serum 25 hydroxyvitamin D (25(OH)D) levels have been linked to OSAS susceptibility. Serum 25(OH)D levels have been negatively correlated with serum IL-6 levels in patients with chronic inflammation. No data exist to assess whether there is a correlation between 25(OH)D and IL-6 serum levels in OSAS, while the impact of continuous positive airway pressure (CPAP) therapy on IL-6 or 25(OH)D levels needs further investigation. We aimed to compare the serum 25(OH)D and IL-6 levels between OSAS patients and controls, examine a possible correlation between 25(OH)D and IL-6 levels and the changes of their concentrations after twelve months of CPAP therapy in OSAS patients. Methods15 newly-diagnosed OSAS patients and 15 non-apneic controls were recruited. Serum IL-6 and 25(OH)D levels were measured in the study population at baseline and twelve months after CPAP initiation in OSAS patients. ResultsIL-6 levels were elevated in OSAS patients than controls and were positively and negatively correlated with body mass index (BMI) and minimum oxyhemoglobin saturation (minSpO2), respectively. Diabetes mellitus, BMI and minSpO2 independently predicted IL-6 levels. No difference was found in 25(OH)D levels between groups. No correlation between IL-6 and 25(OH)D levels was detected. Effective CPAP therapy did not impact IL-6 or 25(OH)D levels after one year in OSAS patients. ConclusionsNo correlation between IL-6 and 25(OH)D levels was found. IL-6 levels were significantly elevated in OSAS patients than the controls and positively correlated with BMI, diabetes mellitus, and nocturnal hypoxemia