Respiratory Dysfunction in Alzheimer's Disease-Consequence or Underlying Cause? Applying Animal Models to the Study of Respiratory Malfunctions.

Alzheimer's disease (AD) is a neurodegenerative brain disease that is the most common cause of dementia among the elderly. In addition to dementia, which is the loss of cognitive function, including thinking, remembering, and reasoning, and behavioral abilities, AD patients also experience respiratory disturbances. The most common respiratory problems observed in AD patients are pneumonia, shortness of breath, respiratory muscle weakness, and obstructive sleep apnea (OSA). The latter is considered an outcome of Alzheimer's disease and is suggested to be a causative factor. While this narrative review addresses the bidirectional relationship between obstructive sleep apnea and Alzheimer's disease and reports on existing studies describing the most common respiratory disorders found in patients with Alzheimer's disease, its main purpose is to review all currently available studies using animal models of Alzheimer's disease to study respiratory impairments. These studies on animal models of AD are few in number but are crucial for establishing mechanisms, causation, implementing potential therapies for respiratory disorders, and ultimately applying these findings to clinical practice. This review summarizes what is already known in the context of research on respiratory disorders in animal models, while pointing out directions for future research.

Cut-off points of neck and waist circumference as predictors of obstructive sleep apnea in the Colombian population: a comparison with polysomnography

ABSTRACT BACKGROUND: Neck circumference (NC) is a useful anthropometric measure for predicting obstructive sleep apnea (OSA). Ethnicity and sex also influence obesity phenotypes. NC cut-offs for defining OSA have not been established for the Latin American population. OBJECTIVES: To evaluate NC, waist circumference (WC), and body mass index (BMI) as predictors of OSA in the Colombian population and to determine optimal cut-off points. DESIGN AND SETTING: Diagnostic tests were conducted at the Javeriana University, Bogota. METHODS: Adults from three cities in Colombia were included. NC, WC, and BMI were measured, and a polysomnogram provided the reference standard. The discrimination capacity and best cut-off points for diagnosing OSA were calculated. RESULTS: 964 patients were included (57.7% men; median age, 58 years) and 43.4% had OSA. The discrimination capacity of NC was similar for men and women (area under curve, AUC 0.63 versus 0.66, P = 0.39) but better for women under 60 years old (AUC 0.69 versus 0.57, P < 0.05). WC had better discrimination capacity for women (AUC 0.69 versus 0.57, P < 0.001). There were no significant differences in BMI. Optimal NC cut-off points were 36.5 cm for women (sensitivity [S]: 71.7%, specificity [E]: 55.3%) and 41 cm for men (S: 56%, E: 62%); and for WC, 97 cm for women (S: 65%, E: 69%) and 99 cm for men (S: 53%, E: 58%). CONCLUSIONS: NC and WC have moderate discrimination capacities for diagnosing OSA. The cut-off values suggest differences between Latin- and North American as well as Asian populations.

Clinical, polysomnographic, and heart rate variability in highland obstructive sleep apnea patients responding to one-night nocturnal oxygen supplementation: A post-hoc analysis from a randomized, crossover trial.

OBJECTIVE: /Background: This study aimed to explore the clinical, polysomnographic, and heart rate variability (HRV) characteristics of highland obstructive sleep apnea (OSA) patients receiving one-night nocturnal oxygen supplementation (NOS) and to identify factors predicting response. PATIENTS/METHODS: Thirty-four highland OSA patients living in Shangri-La were randomly assigned to receive NOS and sham oxygen in a randomized, placebo-controlled, crossover trial. Clinical assessments, polysomnography, and HRV were measured. A responder was defined as a ≥50% reduction in apnea-hypopnea index (AHI) with NOS compared with sham oxygen. RESULTS: Eighteen participants responded and 16 did not respond, with a median (interquartile range [IQR]) age of 46.5 (36.5-53.0) and 48.0 (44.3-53.3) years, respectively. The median treatment effect (95% CI) on total AHI was -23.2/h (-30.0 to -17.5) and -12.0/h (-16.6 to -7.6) in responders and non-responders (p = 0.004), with similar effects on oxygen desaturation index. The mean OAH duration was prolonged by 7 s in responders together with improved sleep quality and daytime blood pressure. The mean OAH duration at baseline predicted responses to NOS with a sensitivity and specificity of 88.9% and 68.7% (AUC 0.809) at a cut-off point of 24.9 s. Changes in HRV parameters were negatively correlated with changes in mean oxygen saturation and daytime systolic blood pressure only in responders. CONCLUSIONS: NOS significantly improved OSA severity and clinical outcomes in responders, which was related to improvements in parasympathetic activity. Highlanders with shorter mean OAH may be suitable candidates for NOS. These findings provide new information about tailored treatment strategies for highland OSA patients.

[Activity of the telomerase complex before and after CPAP therapy in patients with obstructive sleep apnea syndrome]. / Aktivnost' telomeraznogo kompleksa na fone SIPAP-terapii u patsientov s sindromom obstruktivnogo apnoe sna.

OBJECTIVE: To evaluate changes in the activity of the telomerase complex in patients with obstructive sleep apnea (OSA) before and after continuous positive airway pressure (CPAP) therapy. MATERIAL AND METHODS: In accordance with the objectives of the stages of the study of telomers-telomerase relationships, we maintained the unified design of the study described earlier. The main group 1 (MG1), n=35, consisted of men, aged 53.4 [45.5-60.1] years with characteristic complaints indicating of OSA. The main group 2 (MG2) included the same patients before and after 6 months of CPAP therapy. Blood sampling was performed after the first diagnostic polysomnography (PSG) and after 6 months of CPAP in the morning after the second PSG. The control group (CG) consisted of 26 men, comparable in age and the presence of chronic diseases. Questionnaire, PSG and blood sampling were conducted in CG as well. All participants signed an informed consent. RESULTS: As a result of the STOP-BANG questionnaire conducted before PSG, all patients in the MG1 had scores from 5 to 8. The scores on the Epworth scale were more than 5 points. In the MG2 apnea-hypopnea index decreased from 20.1 to 6.4 ev/hour, the desaturation index decreased from 15.6 to 7.1 ev/hour after 6 months of CPAP. Statistically significant differences in changes in the activity of the telomerase complex were revealed, which after treatment significantly exceed the values of these indicators before treatment. So, telomerase reverse transcriptase value was 0.04 (0.009; 0.06) in the MG1, after treatment it was 0.07 (0.06; 0.09) in the MG2 and 0.134 (0.009; 0.18) in the CG. Telomerase RNA subunit TER1 values were 0.06 (0.03; 0.09), 0.07 (0.05; 0.09) and 0.136 (0.04; 0.17), respectively. However, despite the activation of the telomerase complex during CPAP therapy in patients with OSA, in the CG its activity is significantly higher in comparison with the MG1 and MG2. CONCLUSION: In OSA accompanied by intermittent hypoxia, a decrease in the activity of the telomerase complex was shown. Elimination of nocturnal hypoxia and improvement of breathing during sleep is accompanied by an increase in the activity of the components of the telomerase complex.

The Interpretation of Arterial Blood Gas During the Apneic Phase of a Patient With Obstructive Sleep Apnea: A Case Report.

Obstructive sleep apnea (OSA) is now increasingly recognized as a disease entity that can play a major role in affecting multiple organ systems. Even though the symptoms of OSA were first described in the 19th century as Pickwickian syndrome, there are a lot of things that came to be known only recently including its pathophysiology and diagnosis. In this case report, we present some findings that mostly have not been reported in OSA patients before. It has been reported that OSA patients have a typical arterial blood gas (ABG) picture of raised bicarbonate (HCO3-) levels, which also aid in adding to the diagnosis, but we found some more findings that are only specific to the apneic phase of the disease. A 65-year-old female patient was put on a ventilator due to dengue-associated acute respiratory distress syndrome (ARDS). She was also diagnosed with obstructive sleep apnea after facing difficulty in weaning from a ventilator. Post extubation, she was put on noninvasive ventilation (NIV), but the patient's arterial blood gas (ABG) drawn during the apneic phase was showing signs of severe metabolic acidosis even on NIV. This was reversible and gets corrected once the patient is awakened or put on NIV. Clinical decisions from ABG in a patient with OSA may result in errors especially when the ABG is drawn during the apneic phase of the disease. Clinicians have to be careful of this phenomenon, and more research needs to be undertaken to fully understand the pathophysiology of this phenomenon.

Predictive Power of Oxygen Desaturation Index (ODI) and Apnea-Hypopnea Index (AHI) in Detecting Long-Term Neurocognitive and Psychosocial Outcomes of Sleep-Disordered Breathing in Children: A Questionnaire-Based Study.

Pediatric obstructive sleep apnea can negatively affect children's neurocognitive function and development, hindering academic and adaptive goals. Questionnaires are suitable for assessing neuropsychological symptoms in children with sleep-disordered breathing. The study aimed to evaluate the effectiveness of using the Oxygen Desaturation Index compared to the Obstructive Apnea-Hypopnea Index in predicting long-term consequences of sleep-disordered breathing in children. We conducted a retrospective analysis of respiratory polysomnography recordings from preschool and school-age children (mean age: 5.8 ± 2.8 years) and followed them up after an average of 3.1 ± 0.8 years from the home-based polysomnography. We administered three validated questionnaires to the parents/caregivers of the children by phone. Our results showed that children with an Oxygen Desaturation Index (ODI) greater than one event per hour exhibited symptoms in four domains (physical, school-related, Quality of Life [QoL], and attention deficit hyperactivity disorder [ADHD]) at follow-up, compared to only two symptoms (physical and school-related) found in children with an Obstructive Apnea-Hypopnea Index greater than one event per hour at the time of diagnosis. Our study also found a significant correlation between the minimum SpO2 (%) recorded at diagnosis and several outcomes, including Pediatric Sleep Questionnaire (PSQ) scores, physical, social, and school-related outcomes, and ADHD index at follow-up. These results suggest that the Oxygen Desaturation Index could serve as a valuable predictor of long-term symptoms in children with sleep-disordered breathing, which could inform treatment decisions. Additionally, measuring minimum SpO2 levels may help assess the risk of developing long-term symptoms and monitor treatment outcomes.

Sleep apnea-COPD overlap syndrome is associated with larger left carotid atherosclerotic plaques.

Background: Little is known about whether the overlap syndrome (OS) combining features of chronic obstructive pulmonary disease (COPD) and sleep apnea-hypopnea syndrome increases the risk of stroke associated with COPD itself. Methods: We prospectively studied 74 COPD patients and 32 subjects without lung disease. Spirometry and cardiorespiratory polygraphy were used to assess the pulmonary function of the study population and ultrasound measurements of intima media thickness (IMT) as well as the volume of plaques in both carotid arteries were also evaluated. Results: Polygraphic criteria of OS were met in 51% of COPD patients. We found that 79% of patients with OS and 50% of COPD patients without OS had atherosclerotic plaques in the left carotid artery (p = 0.0509). Interestingly, the mean volume of atherosclerotic plaques was significantly higher in the left carotid artery of COPD patients with OS (0.07 ± 0.02 ml) than in those without OS (0.04 ± 0.02 ml, p = 0.0305). However, regardless of the presence of OS, no significant differences were observed in both presence and volume of atherosclerotic plaques in the right carotid artery of COPD patients. Adjusted-multivariate linear regression revealed age, current smoking and the apnea/hypopnea index (OR = 4.54, p = 0.012) as independent predictors of left carotid atherosclerotic plaques in COPD patients. Conclusions: This study suggests that the presence of OS in COPD patients is associated with larger left carotid atherosclerotic plaques, indicating that OS might be screened in all COPD patients to identify those with higher risk of stroke.

[Changes in the telomeres length in patients with obstructive sleep apnea after continuous positive airway pressure therapy: a pilot study]. / Izmenenie otnositel'noi dliny telomer u patsientov s sindromom obstruktivnogo apnoe sna na fone SIPAP-terapii: pilotnoe issledovanie.

OBJECTIVE: To evaluate a relative telomere length in patients with obstructive sleep apnea (OSA) before and after a 6-month course of continuous positive airway pressure (CPAP) therapy. MATERIAL AND METHODS: Seventy-five men participated in the study, including 50 men with OSA (the main group 1) and 25 men without OSA (the control group). The average age in the total group was 53.4±3.6 years. Thirty-five men completed the study (the main group 2). According to the design, night polysomnography (PSG) was performed for all the subjects, blood sampling to assess the length of telomeres was carried out in the morning according to the standard method. The values of the relative telomere length were obtained using the difference between the values of the threshold cycles for telomeric DNA and the reference gene albumin (∆CCt). After clarifying the diagnosis, CPAP was applied for 6 months. RESULTS: Statistically significant indicators of PSG were revealed: a decrease in NREM 3 in patients with OSA compared to controls (89.3±15.8 versus 150±23.4 minutes), an increase in NREM1-2 in OSA (296.2±31.1 and 170.1±24.5, respectively), REM was 84.6±15.4 in the main group and 118.5±19.5 in the control group. CPAP therapy conducted for 6 months (at least 4-5 nights a week, lasting at least 5-6 hours of night sleep) demonstrated a significant improvement in the qualitative and quantitative parameters of sleep. In patients of the main group 1, there is a shortening of the telomere length compared with the control group (p<0.001). With the elimination of hypoxia and improvement of the structure of sleep after CPAP, there was an increase in the telomere lengths in the main group 1 from 0.28 [0.24-0.29] to 0.32 [0.30-0.34] in the main group 2 (p=0.03). The telomers length in the control group was 0.53 [0.50-0.55]. CONCLUSION: Intermittent hypoxia and fragmentation of sleep in OSA leads to shortening of telomeres. CPAP, by eliminating the pathophysiological triggers of OSA, contributes to an increase in telomeres lengths and can slow down the premature aging in OSA.

Dispositivos de Avance Mandibular para el Manejo del Ronquido y la Apnea del Sueño. Actitudes de los Odontólogos Generales y los Especialistas Médicos para Proporcionarlos

RESUMEN: El objetivo de este estudio fue determinar las actitudes y la conciencia de los odontólogos y especialistas médicos sobre la provisión de dispositivos de avance mandibular (DAM) para el tratamiento de los ronquidos y la apnea del sueño. Se llevó a cabo un estudio observacional descriptivo de corte transversal, donde se seleccionaron por conveniencia 53 odontólogos (generales y especialistas) y 5 médicos especialistas en medicina del sueño en la ciudad de Guadalajara, México. Quienes respondieron un cuestionario específico desarrollado por Jauhar et al. (2008) dirigido a conocer la actitud de los odontólogos y médicos especialistas para la provisión de los DAM y otros aspectos relacionados con el ronquido y la apnea obstructiva del sueño (AOS). El 94 % de los odontólogos respondió estar interesado en capacitarse en ronquido y AOS. Y en el grupo de los médicos especialistas se encontró que el 80 % cree que los odontólogos sí tienen un papel para ayudar a los pacientes con ronquido y AOS, el 60 % cree que los odontólogos pueden contribuir con la realización de DAM y el 40 % considera que los odontólogos deben remitir a un especialista del sueño. Existe una actitud muy positiva de los odontólogos para ser parte del grupo interdisciplinario para el tratamiento del ronquido y de la apnea obstructiva del sueño, pero este estudio nos muestra además que a pesar de la disposición para utilizar los DAM, la formación y capacitación no es suficiente. Por otra parte, hay una actitud positiva de los médicos especialistas que consideran que los odontólogos juegan un papel importante en ayudar a los pacientes con ronquidos o con apnea del sueño, pero se evidencia que en su gran mayoría no usan los DAM como parte de un posible tratamiento.

ABSTRACT: The objective of this study was to determine the attitudes and awareness of dentists and medical specialists on the provision of mandibular advancement devices (MAD) for the treatment of snoring and sleep apnea. This is a cross-sectional descriptive observational study, where 53 dentists (general and specialists) and 5 sleep medicine specialists in the city of Guadalajara, Mexico were selected for convenience. The selected group answered a specific questionnaire developed by Jauhar et al., to know the attitude of dentists and medical specialists for the provision of MAD and other aspects related to snoring and obstructive sleep apnea (OSA). 94 % of dentists responded to be interested in training in snoring and OSA. And of the group of medical specialists, 80 % consider that dentists have a role in helping patients with snoring and OSA, 60 % believe that dentists can contribute to MAD and 40 % believe that dentists should refer a sleep specialist. There is a very positive attitude by the dentists to be part of the interdisciplinary group for the treatment of snoring and obstructive sleep apnea, but this study also shows that despite the willingness to use MAD, education and training is not enough. There is a positive attitude of specialist doctors who consider that dentists play an important role in helping patients with snoring or with sleep apnea, but it is evident that the majority do not use MAD as part of a possible treatment.

Effect of modified genioglosuss advancement on hyoid bone position: Cephalometric study.

OBJECTIVE: To assess Hyoid bone position and retrolingual airway space after Modified Genioglossus Advancement Surgery by cephalometry in patients with obstructive sleep apnea (OSA). STUDY DESIGN: Prospective study. SETTING: Zagazig University Hospital. METHODS: Eighteen patients with moderate to severe OSA having multilevel airway obstruction confirmed by fiberoptic endoscopy during Muller's maneuver and DISE. All patients underwent modified genioglossus advancement surgery associated with antrolateral advancement pharyngoplasty. Beside Polysomnography and Drug induced sleep endoscopy, Cephalometry was done preoperatively and 6 months postoperative. RESULTS: Improved Polysomnography parameters as Postoperative mean ± SD apnea hypopnea index decreased from 52 ± 17.1 to 17 ± 3 (P < 0.001, 95% confidence interval 27.71 to 42.41). LOS increased from 79.89 ± 4.43% to 83 ± 4.05% (P 0.07, 95% confidence interval -0.31 to 6.97). Cephalometry analysis showed a significant difference between preoperative and postoperative findings, including: Retrolingual airway space at three levels significantly increased; Level 1 from 6.1 ± 1.6 to 8.5 ± 1.7, Level 2 from 10.5 ± 2.4 to 13.9 ± 2.1, Level 3 from 15.7 ± 3.1 to 21 ± 4, H-GN decreased from 51 ± 7 to 39 ± 8, H-MP decreased from 31.6 ± 7.7 to 24.9 ± 7.3, HS decreased from 121 ± 15 to 102 ± 12, H-PH increased from 29 ± 8 to 43 ± 9. With a success rate defined as AHI <20 and a 50% decrease in AHI of the preoperative value, the surgical success rate was 83.33%. CONCLUSION: This study showed that Modified genioglossus advancement procedures done for OSA patients significantly changed the position of hyoid bone into a more anterior and superior position and this was reflected in the postoperative Polysomnography.

Diagnostic methods and criteria of obstructive sleep apnea hypopnea syndrome in children / 口腔疾病防治

@#Obstructive sleep apnea hypopnea syndrome (OSAHS), which is a common childhood disease, is a trending topic in clinical multidisciplinary research due to its detriment to the growth and development of children. Due to the wide variety and specificity of pathogenesis and clinical manifestations, the clinical diagnosis of OSAHS is sophisticated and difficult and remains controversial in the field. This review summarizes the common diagnostic methods in OSAHS for children, including polysomnography,which is known as the current “gold standard”, pulse oximetry, fiberoptic nasopharyngoscopy, nasopharyngeal lateral X-ray, CT, and magnetic resonance imaging (MRI). Furthermore, it emphasizes the new diagnostic critical value from Chinese guidelines for the diagnosis and treatment of obstructive sleep apnea in children (2020) for children with OSAHS released by China in 2020: the obstructive apnea hypopnea index (OAHI) is ≥ 1 time/h; it also emphasizes the importance of history and physical examination to contribute to clinical diagnosis and treatment for children with OSAHS.

Automatic Separation of Respiratory Flow from Motion in Thermal Videos for Infant Apnea Detection.

Both Respiratory Flow (RF) and Respiratory Motion (RM) are visible in thermal recordings of infants. Monitoring these two signals usually requires landmark detection for the selection of a region of interest. Other approaches combine respiratory signals coming from both RF and RM, obtaining a Mixed Respiratory (MR) signal. The detection and classification of apneas, particularly common in preterm infants with low birth weight, would benefit from monitoring both RF and RM, or MR, signals. Therefore, we propose in this work an automatic RF pixel detector not based on facial/body landmarks. The method is based on the property of RF pixels in thermal videos, which are in areas with a smooth circular gradient. We defined 5 features combined with the use of a bank of Gabor filters that together allow selection of the RF pixels. The algorithm was tested on thermal recordings of 9 infants amounting to a total of 132 min acquired in a neonatal ward. On average the percentage of correctly identified RF pixels was 84%. Obstructive Apneas (OAs) were simulated as a proof of concept to prove the advantage in monitoring the RF signal compared to the MR signal. The sensitivity in the simulated OA detection improved for the RF signal reaching 73% against the 23% of the MR signal. Overall, the method yielded promising results, although the positioning and number of cameras used could be further optimized for optimal RF visibility.

Objective measurements for upper airway obstruction in infants with Robin sequence: what are we measuring? A systematic review.

STUDY OBJECTIVES: Identifying optimal treatment for infants with Robin sequence (RS) is challenging due to substantial variability in the presentation of upper airway obstruction (UAO) in this population. Objective assessments of UAO and treatments are not standardized. A systematic review of objective measures of UAO was conducted as a step toward evidence-based clinical decision-making for RS. METHODS: A literature search was performed in the PubMed and Embase databases (1990-2020) following PRISMA guidelines. Articles reporting on RS and UAO treatment were included if the following objective measures were studied: oximetry, polysomnography, and blood gas. Quality was appraised by the methodological index for nonrandomized studies (range: 0-24). RESULTS: A total of 91 articles met the inclusion criteria. The mean methodological index for nonrandomized studies score was 7.1 (range: 3-14). Polysomnography was most frequently used (76%) followed by oximetry (20%) and blood gas (11%). Sleep position of the infant was reported in 35% of studies, with supine position most frequently, and monitoring time in 42%, including overnight recordings, in more than half. Of 71 studies that evaluated UAO interventions, the majority used polysomnography (90%), of which 61% did not specify the polysomnography technique. Reported polysomnography metrics included oxygen saturation (61%), apnea-hypopnea index (52%), carbon dioxide levels (31%), obstructive apnea-hypopnea index (27%), and oxygen desaturation index (16%). Only 42 studies reported indications for UAO intervention, with oximetry and polysomnography thresholds used equally (both 40%). In total, 34 distinct indications for treatment were identified. CONCLUSIONS: This systematic review demonstrates a lack of standardization, interpretation, and reporting of assessment and treatment indications for UAO in RS. An international, multidisciplinary consensus protocol is needed to guide clinicians on optimal UAO assessment in RS. CITATION: Logjes RJH, MacLean JE, de Cort NW, et al. Objective measurements for upper airway obstruction in infants with Robin sequence: what are we measuring? A systematic review. J Clin Sleep Med. 2021;17(8):1717-1729.

Ambulatory blood pressure monitoring in children undergoing polysomnography.

Ambulatory blood pressure monitoring (ABPM) is recommended for the diagnosis of hypertension in children at high risk, such as children with obesity or obstructive sleep apnea (OSA). Nocturnal hypertension is highly predictive of cardiovascular outcomes. ABPM allows for early detection of nocturnal hypertension in children. Although OSA is the most common sleep disorder associated with hypertension, studies have also shown an increase in cardiovascular risk in adult patients with other sleep disorders; therefore, there is an imperative need to provide early diagnosis in children at high risk. In the present study, we evaluated the feasibility of using ABPM during polysomnography (PSG) in children referred for sleep disordered breathing to the Seattle Children's Hospital Sleep Disorders Center. A total of 41 children aged 7-18 years were included in this study. The ABPM monitor was worn for a mean (SD) of 10.2 (1.5) hr. No significant changes were seen in PSG parameters when ABPM was co-performed with PSG, including sleep efficiency and arousals. In total, 12 of the 41 patients were identified as having nocturnal hypertension. Our study is important in that it shows that concomitant use of ABPM during PSG can aid in the early identification of nocturnal hypertension in this population.

Angioid streaks and obstructive sleep apnea syndrome: are they related?

BACKGROUND: Sleep apnea syndrome (OSAS) has been associated with different ocular manifestations including glaucoma, floppy eye syndrome, punctate keratitis, keratoconus, and optic neuropathy. Angioid streaks are mainly associated with pseudoxanthoma elasticum (PXE) although they can appear in other systemic conditions affecting the elastic fibers. METHODS: This is a prospective, cross-sectional study. A complete ophthalmic examination was performed in 92 patients undergoing overnight polysomnography for suspicion of OSAS. Diagnosis and classification of OSAS were made based on apnea-hypopnea index (AHI). Stereoscopic optic disc photographs were taken in all patients and independently evaluated by two ophthalmologists. Patients with angioid streaks were referred to a dermatologist for axillary skin biopsy in order to rule out pseudoxanthoma elasticum or other skin abnormalities. RESULTS: Bilateral angioid streaks were observed in three patients who had been diagnosed with severe OSAS (AHI > 30/h). No clinical features characteristic of pseudoxanthoma elasticum or other pathological skin signs were observed. Skin biopsies were normal for all three patients, supporting the diagnosis of idiopathic angioid streaks. One of the patients developed bilateral choroidal neovascularization secondary to the angioid streaks over subsequent years. CONCLUSIONS: In view of the low prevalence of idiopathic angioid streaks in the general population, the finding of angioid streaks in patients with severe OSAS suggests OSAS as a possible risk factor for its development. The hypothesis of a connective tissue abnormality that could explain an association between both entities deserves further elucidation.

Cognitive impairment in obstructive sleep apnea syndrome: a descriptive review.

PURPOSE: Obstructive sleep apnea syndrome is a clinical sleep disorder defined by total or partial airflow restraint during sleep that results in fragmented sleep and hypoxemia, impacting negatively with cognitive functioning. This review was conducted on studies investigating structural brain alteration and cognitive impairment in obstructive sleep apnea syndrome. METHOD: We searched on PubMed databases and screening references of included studies and review articles for additional citations. From initial 190 publications, only 17 met search criteria and described the cognitive impairment in obstructive sleep apnea syndrome. RESULTS: Findings showed that patients with this syndrome had worse performance than healthy controls in attention, memory, and executive functions, showing specific neuroanathomical features. Cognitive impairment is also related to the severity of pathology. Treatment could improve certain cognitive aspects. CONCLUSIONS: Cognitive deficits seem to be mainly attributable to decreased daytime vigilance and nocturnal hypoxemia.

CPAP Therapeutic Options for Obstructive Sleep Apnea.

INTRODUCTION: There are many options available to patients who are placed on constant positive airway pressure (CPAP) for obstructive sleep apnea. Despite the success of CPAP in correcting apnea, a significant number of patients have difficulty with the therapy. A large number of those patients who have difficulty stop therapy and are often labeled as "CPAP Failure". Non-sleep specialists may view CPAP therapy as a singular course of treatment, but there are many ways CPAP may be ordered for a patient. Each patient experiences a unique set of options that constitute a unique order set. METHODS: In order to demonstrate the magnitude of the possible options, estimates of the number of unique order sets were calculated. The author chose individual order options and the number of selections possible within each option. The calculated sets included a "Generous, Limited and Minimal" number of selections for each option. Calculations were done separately for standard CPAP and for auto-adjusting CPAP. Additional calculations were performed using the number of commercially available masks in the United States. RESULTS: The maximum number of unique order sets was seen using a standard CPAP combined with commercially available masks: 49,152 unique order sets. The fewest number of unique order sets were seen with the auto-adjusting CPAP and the "Minimal" selections: 288 unique order sets. DISCUSSION: There are a large number of unique CPAP orders that a patient may experience. CPAP treatment is not a singular or simple therapy. When evaluating obstructive sleep apnea patients with histories of CPAP failure or prior difficulty with CPAP, paying close attention to the patient's treatment experiences may help explain a significant number of those patients' CPAP therapy problems.

Distinguishing Obstructive Versus Central Apneas in Infrared Video of Sleep Using Deep Learning: Validation Study.

BACKGROUND: Sleep apnea is a respiratory disorder characterized by an intermittent reduction (hypopnea) or cessation (apnea) of breathing during sleep. Depending on the presence of a breathing effort, sleep apnea is divided into obstructive sleep apnea (OSA) and central sleep apnea (CSA) based on the different pathologies involved. If the majority of apneas in a person are obstructive, they will be diagnosed as OSA or otherwise as CSA. In addition, as it is challenging and highly controversial to divide hypopneas into central or obstructive, the decision about sleep apnea type (OSA vs CSA) is made based on apneas only. Choosing the appropriate treatment relies on distinguishing between obstructive apnea (OA) and central apnea (CA). OBJECTIVE: The objective of this study was to develop a noncontact method to distinguish between OAs and CAs. METHODS: Five different computer vision-based algorithms were used to process infrared (IR) video data to track and analyze body movements to differentiate different types of apnea (OA vs CA). In the first two methods, supervised classifiers were trained to process optical flow information. In the remaining three methods, a convolutional neural network (CNN) was designed to extract distinctive features from optical flow and to distinguish OA from CA. RESULTS: Overnight sleeping data of 42 participants (mean age 53, SD 15 years; mean BMI 30, SD 7 kg/m2; 27 men and 15 women; mean number of OA 16, SD 30; mean number of CA 3, SD 7; mean apnea-hypopnea index 27, SD 31 events/hour; mean sleep duration 5 hours, SD 1 hour) were collected for this study. The test and train data were recorded in two separate laboratory rooms. The best-performing model (3D-CNN) obtained 95% accuracy and an F1 score of 89% in differentiating OA vs CA. CONCLUSIONS: In this study, the first vision-based method was developed that differentiates apnea types (OA vs CA). The developed algorithm tracks and analyses chest and abdominal movements captured via an IR video camera. Unlike previously developed approaches, this method does not require any attachment to a user that could potentially alter the sleeping condition.

Obstructive sleep apnea intensifies stroke severity following middle cerebral artery occlusion.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a sleep disorder caused by transient obstruction of the upper airway and results in intermittent hypoxia, sleep fragmentation, sympathetic nervous system activation, and arousal which can have an adverse effect on cardiovascular disease. It is theorized that OSA might intensify stroke injury. Our goal here was to develop a new model of experimental OSA and test its ability to aggravate behavioral and morphological outcomes following transient brain ischemia/reperfusion. METHODS: We used a 3D printed OSA device to expose C57BL6 mice to 3 h of OSA (obstructive apnea index of 20 events per hour) for three days. These mice were then subjected to ischemia/reperfusion using the middle cerebral artery occlusion model (MCAO) stroke and examined for overall survival, infarct size and neurological scoring. RESULTS: We found that OSA transiently decreased respiration and reduced oxygen saturation with bradycardia and tachycardia typical of human responses during apneic events. Brain injury from MCAO was significantly increased by OSA as measured by infarct size and location as well as by intensification of neurological deficits; mortality following MCAO was also increased in OSA animals. CONCLUSIONS: Our findings suggest that our new model of OSA alters respiratory and cardiovascular physiological functions and is associated with enhanced ischemia/reperfusion mediated injury in our non-invasive, OSA intensified model of stroke.

African ethnicity is associated with a higher prevalence of diabetes in obstructive sleep apnea patients: results of a retrospective analysis.

PURPOSE: Obstructive sleep apnea (OSA) syndrome is a well-recognized independent risk factor for cardiovascular disease and its prevalence is increasing. OSA symptomology, polysomnographic features, and comorbidities are heterogeneous among patients. Ethnicity is thought to influence OSA phenotypes, but extensive knowledge of OSA ethnic patterns is lacking. The primary aim of the present study was to compare comorbidities in Caucasian and African OSA. Secondary aims were to observe OSA symptomatology, polysomnographic characteristics, and CPAP adherence in these two ethnic groups. METHODS: In this retrospective study, 1717 patients suffering from moderate/severe OSA were included between 2013 and 2017. Data on demographics, symptomatology, comorbidities, polysomnographic characteristics, and CPAP adherence were collected. Data were analyzed to identify potential differences between Caucasians and Africans. RESULTS: Despite healthier lifestyles and lower BMI, a higher prevalence of diabetes but less cardiac comorbidities and dyslipidemia was observed in the African population. Younger African patients (< 56 years) suffered more from cognitive impairment than Caucasians and both younger and older Africans complained more of nighttime choking than Caucasians. In analysis of polysomnographic data, Africans had higher apnea-hypopnea index (AHI) in REM sleep, lower supine AHI, lower desaturation time, and lower periodic leg movements index. CONCLUSIONS: Compared with Caucasians, African OSA showed a particular comorbidity profile. There are younger patients who exhibit more diabetes but less cardiac comorbidities than the Caucasians. African diabetics should be more promptly referred for OSA testing. Moreover, as they suffer more often from choking and cognitive impairment, OSA treatment could positively impact their quality of life.