Median AHI Research Articles

Alteration of Auto-CPAP requirements in obstructive sleep apnea patients with COVID-19 history

BackgroundCoronavirus disease 2019 (COVID-19) is an infectious disease that leads to critical respiratory problems.Obstructive sleep apnea (OSA) is the most common sleep-associated breathing disease and is represented by repetitive experiences of constraint of the respiratory tract prompting to reduced or deficient breathing during sleep.Auto-Continuous positive airway pressure (Auto-CPAP) is a modality of respiratory ventilation used as gold standart in the treatment of OSA. ObjectiveThis study was performed to conclude the alteration of Auto-CPAP levels in OSA patients who had COVID-19 history. MethodsNineteen OSA patients who had cured COVID-19 and used Auto-CPAP were included in this study. Nightly Auto-CPAP 95th percentile pressure (95thpp), median CPAP pressure and AHI before COVID-19 disease and one month after COVID therapy were recorded from electronic cards of Auto-CPAP devices. ResultsBefore COVID infection, average Auto-CPAP 95thpp was 8.56 ± 0.17 cm H2O. One month after COVID-19, average Auto-CPAP 95thpp was 9.78 ± 0.21 cm H2O (P < 0.01). While Median CPAP pressure was 7.49 ± 0.16 cm H2O before COVID, it was found to be 8.15 ± 0.19 cm H2O after the disease (P < 0.01). ConclusionsThe increase in need of average Auto-CPAP 95thpp and median CPAP pressure in OSA patients who have had COVID-19 disease and use Auto-CPAP shows that this disease causes problems in both the lower and upper airways.

Evaluation of sleep apnea prevalance among driving license applicants

Aim: This study aimed at evaluating the PSG results of the applicants of driving license by reference to the BMI, and investigating the accuracy of this cutoff value of BMI (33) on detecting the patients with OSAS among the applicants of driving licenseMaterials and Methods: Driving license applicants with a BMI 36 constituted the group B. The AHI levels of the groups were compared, and ROC analyzes were performed to detect accurate BMI values. Results: Median AHI values did significantly differ among three groups (p0.001). median AHI was statistically significantly higher in group A (median AHI: 12.5) and in group B (median AHI: 12.9) compared to the control group (median AHI: 2.4) (p0.001). However, there was no significant difference between the median AHI of the group A and B (median AHI: 12.5 vs. 12.9) (p= 0.336). Additionally, 34 was found to be the cut-off value for BMI suggesting that AHI could be 15 and/or above; and 34.8 was found to be the cut-off value for BMI suggesting that AHI could be 30 and/or above. Conclusion: Patients with a BMI over 33 had a greater AHI compared to the patients. Additionally, 34.8 value was found to be the cut-off value for BMI suggesting that AHI could be 30 and/or above.

Association of Obstructive Sleep Apnea with Nocturnal Hypoxemia in Metabolic-Associated Fatty Liver Disease Patients: A Cross-sectional Analysis of Record-based Data.

Rationale:Obstructive sleep apnea (OSA) is often seen among obese individuals and the obesity has a linear association with MAFLD. The contribution of chronic intermittent nocturnal hypoxia of OSA and association of MAFLD with OSA is an unmet need. The present study aimed to determine the etiology, impact and association of OSA severity and nocturnal hypoxemia among patients ofChronic liver disease (CLD).Methods:In this study, analysis of the medical records and clinical details of the patients of CLD who had undergone polysomnography were analyzed after appropriate inclusion in study as per inclusion and exclusion criteria. After assessing the eligibility criteria, a total of 78 patients were included in the final analysis. Nocturnal hypoxemia was gauged from the baseline oxygen saturation record of study. Presence and severity of OSA were graded as per American Academy of Sleep Medicine (AASM) criteria. The primary objective of the study was to determine the association between OSA severity and nocturnal hypoxemia to the presence of Non-alcoholic Fatty Liver Disease (NAFLD). Secondary objectives were to assess the association of OSA severity and extent of nocturnal hypoxemia to the BMI and to determine the proportions of NAFLD subjects with OSA.Results:A total of 78 patients were screened, of which only 11 (14.1%) were female. Out of these, 56 (71.8%) were classified to MAFLD group while 22 (28.2%) were to the non-MAFLD group. The patients in MAFLD group with mean age of 56.02 years were older as compared to non-MAFLD with mean age of 51.05 years but that was not statistically different. Patients were categorized into MAFLD (n = 56) and non-MAFLD, representing other etiologies of CLD (n = 22; ethanol, chronic Hepatitis B virus (HBV), chronic Hepatitis C virus (HCV), cryptogenic, Non-cirrhosis portal fibrosis (NCPF), Primary sclerosing cholangitis (PSC), Autoimmune hepatitis (AIH), sarcoidosis, Wilson's disease). The mean BMI was significantly higher in MAFLD in comparison to non-MAFLD (34.51 ± 8.79 vs. 25.47 ± 5.75; P = 0.000) and also the median AHI of MAFLD group was significantly higher than the non-MAFLD 4.95 {(1.85, 25.47) vs. 0.85 (0.30, 2.72) (P value < 0.000)} [Table 1]. Among the desaturation indices, the number of desaturations >3% {median of 122.50 (75.00, 241.25) vs. 63.00 (13.75, 158.00), P value 0.009} and average desaturation {mean of (5.04 ± 2.16) vs. (3.78 ± 1.226)%, P value 0.002} were significantly higher in MAFLD versus non-MAFLD group [Table 2]. The AHI and all desaturation parameters, although not statistically significant, were worst in Child B [Table 3].Conclusion:MAFLD patients have higher prevalence and greater severity of OSA and worse nocturnal desaturation parameters as compared to non-MAFLD patients. OSA is independent of obesity among patients of CLD, but prevalent among NAFLD group. Further prospective studies are needed among MAFLD and OSA patients to elucidate the mechanism linking pathophysiology of OSA-MAFLD and guide therapy.

Disorders of sleep in spinal and bulbar muscular atrophy (Kennedy's disease).

Spinal and bulbar muscular atrophy (SBMA) is a progressive, X-linked lower motor neuron disorder exclusively affecting men. Since knowledge on sleep disorders in SBMA is scarce compared to other motoneuron diseases, this retrospective case-control study aimed to investigate sleep and sleep-related breathing in patients with SBMA. In 23 non-ventilated patients with SBMA (median age 52 years), clinical disease characteristics, forced vital capacity and diagnostic polysomnographies were retrospectively evaluated. In 16 patients, overnight transcutaneous capnometry was available. Twenty-three male control subjects with chronic insomnia were matched for age and body mass index. In patients with SBMA obstructive sleep apnoea (OSA, apnoea-hypopnoea index/AHI > 5/h) was more frequent than in control subjects (14/23 or 61% vs. 6/23 or 26%, p = 0.02), and median AHI was significantly higher in patients (9.0/h vs. 3.4/h, p < 0.01). Among SBMA patients, the AHI was not related to age or body mass index. Alveolar hypoventilation as reflected by nocturnal hypercapnia was found in 3/16 patients. Rapid eye movement (REM) sleep without atonia was present in 44% of SBMA patients but only in 4% of controls (p < 0.01). During REM and non-REM sleep, no behavioural abnormalities were observed in either group. Periodic limb movements in sleep (index > 15/h) were frequent in SBMA patients but rarely disrupted sleep. In patients with SBMA, sleep-disordered breathing may comprise both OSA and nocturnal hypoventilation. REM sleep without atonia may also be found, but its clinical significance remains unclear. In patients complaining of sleep-related symptoms, cardiorespiratory polysomnography and transcutaneous capnometry are recommended.

Obstructive sleep apnea during rapid eye movement sleep in patients with diabetic kidney disease

Although recent studies suggest that obstructive sleep apnea during rapid eye movement (REM) is associated with different cardiometabolic and neurocognitive risks compared with non-REM (NREM) sleep, there is no information on whether obstructive sleep apnea during REM and/or NREM sleep is independently associated with diabetic kidney disease (DKD). In this cross-sectional study, 303 patients with type 2 diabetes who were followed up at our diabetes outpatient clinic underwent all-night polysomnography. Logistic regression analysis was performed to determine the separate effects of obstructive sleep apnea during REM and/or NREM sleep (REM and/or NREM-apnea-hypopnea index [AHI]) and several other polysomnography parameters on DKD after adjustment for several known risk factors for DKD. The median (interquartile range) AHI, REM-AHI, and NREM-AHI of the patients (age 57.8 ± 11.8 years, male sex 86.8%, hypertension 64.3%, and DKD 35.2%) were 29.8 (18.0-45.4), 35.4 (21.1-53.3), and 29.1 (16.3-45.4) events/h, respectively. REM-AHI quartiles, but not NREM-AHI quartiles, correlated independently and significantly with DKD (P = .03 for linear trend, odds ratio (OR), and 95% confidence interval for Q2: 3.14 (1.10-8.98), Q3: 3.83 (1.26-11.60), Q4: 4.97 (1.60-15.46), compared with Q1). In addition, categorical AHI (P = .01, OR, and 95% confidence interval for ≥ 15 to < 30: 1.54 (0.64-3.71), ≥ 30: 3.08 (1.36-6.94) compared with < 15), quartiles of AHI (P = .01), quartiles of lowest arterial oxyhemoglobin saturation (P < .01), quartiles of percentage of time spent with arterial oxyhemoglobin saturation < 90 (P < .01), and quartiles of mean arterial oxyhemoglobin saturation were independently associated with DKD. Obstructive sleep apnea, especially during REM sleep, is a potential risk factor for DKD.

Sleep-disordered breathing in pediatric heart transplant recipients.

Sleep-disordered breathing is commonly found in adults with heart failure both before and after HTx. Untreated sleep-disordered breathing post-transplant has been linked to late graft dysfunction, reduced quality of life, and increased morbidity. Sleep-disordered breathing has not been investigated in pediatric HTx recipients. We conducted retrospective review of patients <21yo who underwent primary HTx at our center from 2009 to 2019 to describe clinical characteristics, cardiac history, and PSG results. One hundred and fifty patients were included; 60% had congenital heart disease, and 40% had cardiomyopathy. Fifty patients had PSG performed at median age of 6.1years. Forty-one were referred for symptoms of sleep-disordered breathing. Obstructive sleep apnea was diagnosed in 45 patients and central sleep apnea in 3 patients. Of those with first PSG post-transplant (n=36), median AHI was 9.1/h, and 19 (53%) were diagnosed with moderate or severe sleep apnea. Patients diagnosed with obstructive sleep apnea on PSG had more post-transplant ventilator days (median 3 vs 2days, P<.05) and longer post-transplant lengths of stay (median 28 vs 22days, P<.05). In this single-center cohort of pediatric HTx recipients, sleep-disordered breathing was common and associated with longer peri-transplant respiratory support and length of stay. Given the high incidence of moderate and severe OSA detected in this population, clinicians should regularly screen for SDB and consider PSG testing more frequently in children who have undergone HTx. Further study into the long-term impact of sleep-disordered breathing in pediatric HTx recipients is needed.

Associations between hypoxia parameters in obstructive sleep apnea and cognition, cortical thickness, and white matter integrity in middle-aged and older adults.

This study aimed to investigate the association between each parameter of intermittent hypoxia in obstructive sleep apnea (OSA) and the cognitive profile, cortical thickness, and white matter integrity in middle-aged and older adults. Participants were newly diagnosed with moderate or severe OSA from the King Chulalongkorn Memorial Hospital, Bangkok, Thailand. Respiratory parameters from polysomnography were extracted. Each participant was tested on a battery of neuropsychological tests and underwent an MRI scan of the brain. Cortical thickness analysis and diffusion tensor imaging analysis were performed. Participants were classified as having either severe or mild hypoxia based on parameters of hypoxia, i.e., oxygen desaturation index, lowest oxygen saturation, and the percentage of total sleep time spent below 90% oxygen saturation. Of 17patientswith OSA, there were 8men (47%). Median age was 57 years and median AHI was 60.6. Comparison of cortical thicknessbetween the severe and themild group of each hypoxic parameter revealed two clusters of cortical thinning at the right inferior frontal gyrus (p-value = 0.008) and right inferior parietal gyrus (p-value = 0.006) in the severe desaturation group and a cluster of cortical thinning at the superior parietal gyrus (p-value = 0.008) in the high oxygen desaturation index group. There was no difference in cognitive function or white matter integrity between groups. The magnitude of the degree and frequency of desaturations in OSA are associated with a decrease in cortical thickness at the frontal and parietal regions.

0592 Prevalence of Sleep Apnea in Patients with Tracheobronchomalacia

Abstract Introduction Tracheobronchomalacia (TBM) is a pathologic weakness in the trachea and bronchi leading to excessive dynamic narrowing of the airway. A relationship between sleep disordered breathing (SDB) and TBM has been observed before. SBD may be an important contributor to development or progression of TBM. The objective was to determine the Prevalence and characteristics of sleep disordered breathing in patients with tracheobronchomalacia. Methods We performed a retrospective chart review of patients who have been diagnosed with tracheobronchomalacia and who also underwent a polysomnogram (PSG) at the AASM - accredited Sleep Center of Beth Israel Deaconess Medical Center. Results In our 24 patient cohort of TBM, 71% were females, mean age 55 years (SD ± 12.3 years) and mean BMI 31.7 kg/m2 (SD ± 9.4 kg/m2). In patients with TBM we found a sleep apnea prevalence of 62.5% (n= 15), defined as an apnea-hypopnea index&amp;gt;5/hour (hour) with a desaturation greater than 4%. Of the 15 patients, 73.3% (n = 11) had mild sleep apnea, 20% (n = 3) had moderate sleep apnea, 6.6% (n = 1) had severe sleep apnea, defined per the AASM criteria with oxygen desaturation greater than 4%. The TBM cohort had a mean sleep efficiency of 72.7% (SD ± 22.2%) with a mean REM of 16.3% (SD ± 9.8 %). Other characteristics included a median AHI 3% of 19.9/hour (95% CI 3.9 - 25.0), median AHI 4% of 5.5/hour (95% CI 3.9 - 9.3), Respiratory disturbance index of 22/hour (95% CI 15.1 to 28.4). No unique challenges for treatment with positive airway pressure were noted. Conclusion Sleep apnea may be more common in patients with tracheobronchomalacia and could be regularly screened. Support none

0057 Actigraphy-Based Circadian Measures and Cerebrospinal Fluid Biomarkers of Neurodegeneration in Alzheimer’s Disease with Mild Cognitive Impairment

Abstract Introduction Although recent data implicates sleep and circadian disruption to neurodegeneration in Alzheimer’s Disease (AD), the association of objective circadian biomarkers and neurodegeneration remains understudied. We hypothesize that actigraphy-based circadian measures are associated with cerebrospinal fluid (CSF) biomarkers of neurodegeneration in those mild cognitive impairment due to AD (MCI-AD). Methods Eighteen patients with CSF biomarker-confirmed MCI-AD underwent actigraphy monitoring generating the following circadian measures: amplitude, F-ratio and mesor and morning collection of CSF biomarkers of neurodegeneration (Aβ42,t-tau,p-tau). Linear models were used to evaluate the association of circadian and CSF measures; logarithmic transformations were performed on neurodegenerative markers for greater normality. Analysis was performed using SAS software. A significance level of 0.05 was assumed for all tests. Results Eighteen MCI-AD patients who were 68± 6.2 years, 44% female, with median AHI=12 and underwent actigraphy monitoring for 8.2+/-3.2 days were included. There was no significant association of circadian measures and Aβ42 nor with mesor and neurodegeneration biomarkers. Amplitude was associated with both p-tau and t-tau, such that each 10 unit increase in amplitude resulted in a predicted increase in p-tau of 8% (95% CI:1%-15%, p=0.018) and an increase of 13% (3%-23%; p=0.01) in t-tau. F-ratio was positively associated with p-tau and t-tau; each 1000 unit increase in F-ratio resulted in a predicted 12% (4%-22%; p=0.007) increase in P-tau and 20%(6%-35%; p=0.005) increase in t-tau. Associations of these circadian measures and CSF levels of p-tau and t-tau remained statistically significant after adjustment for age and sex. Conclusion Among patients with symptomatic MCI stages of AD, objective measures of circadian rhythm disruption are associated with CSF-based biomarkers of neurodegeneration even after consideration of age and sex. Future investigation should clarify directionality of this association and potential utility of circadian-based interventions in the mitigation of AD progression. Support N/A

0687 Comparative Changes Of Patient Reported Outcomes In Positive Airway Pressure And Upper Airway Stimulation For Obstructive Sleep Apnea

Abstract Introduction Upper Airway Stimulation (UAS) is increasingly being used for obstructive sleep apnea (OSA) treatment, however, data comparing changes in patient reported outcomes (PROs) in response to positive airway pressure (PAP) versus UAS are limited. We hypothesize that there will be no difference in PROs between the two groups after treatment. Methods UAS and PAP groups were 1:3 matched on age, sex, Body Mass Index (BMI) and Apnea Hypopnea Index (AHI, category 15-30, &amp;gt;30). Linear mixed models assessed the difference of change in Epworth Sleepiness Scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ), Patient Health Questionnaire (PHQ9) and Insomnia Severity Index (ISI) measures on matched strata of UAS versus PAP groups with adjustment of baseline and matching factors. All analysis was performed in SAS software (version 9.4, Cary, NC). Results The analytic sample comprised 193 PAP patients and 69 UAS patients, with mean age=62.9+/-9.4 years, 27.5% female, mean BMI=29.1+/-3.2kg/m2, and median AHI 42.7, IQR: 31.5, 57.2. ESS in PAP (n=190) reduced by -2.63 (-3.38,-1.88) and in UAS (n=56) reduced by -2.22 (-3.34, -1.10), with a mean difference of 0.41 (-0.70, 1.52, p=.46). FOSQ in PAP (n=188) showed a change of 1.38 (0.99, 1.78) and in UAS (n=49) a change of 1.82 (1.17, 2.46), with a mean difference of 0.43 (-0.23, 1.09, p=.19). PHQ9 in PAP (n=185) showed a significant change of -2.24(-3.00, 1.47) and in UAS (n=45) a change of -3.75(-5.07,-2.42), with a mean difference of -1.51(-2.93,-0.088, p=.038). ISI in PAP (n=193) showed a significant change of -3.20(-4.39,-2.02) and in UAS (n=47) a change of -4.83(-6.77,-2.90), with a mean difference of -1.63(-3.62, 0.37, p=.11). Conclusion Similar improvements in PROs were observed in both UAS and PAP patient groups, however UAS appeared to confer greater benefit in depressive symptoms relative to PAP. Randomized clinical trials should be designed to confirm these findings. Support N/A

0694 Positive Airway Pressure Use In The Context Of Total Sleep Time

Abstract Introduction Positive airway pressure (PAP) adherence definitions are independent of total sleep time (TST). When PAP efficacy is examined by biophysiologic outcomes in adults with obstructive sleep apnea (OSA), sensitivity and specificity of the measurement of PAP adherence/non-adherence is important. Methods A post-hoc analysis of experimental data: 1) investigated agreement among concurrently-measured objective PAP use, objective and subjective TST; 2) assessed untreated TST among adherers and non-adherers defined by CMS PAP adherence criterion and separately by proportion of TST on PAP criteria (≥65%, ≥75%, ≥85%). Objective TST was measured with wrist actigraphy and concurrent sleep diary on the first five days of PAP use. Objective five day PAP use (hours/night) was abstracted from full record. Analyses included descriptive and exploratory correlations. Results PAP-naïve adults (n=36; 76% male, 84% white) were middle-aged (51±10 years), with severe OSA (median AHI 31.1 events/hr), mean PAP use (371.5±85.4 min), mean objective and subjective TST (417.5±50.6 min, 439.6±58.1 min, respectively) from a single sleep center. Objective TST was correlated with concurrent objective PAP use (r=0.46) and with subjective TST (r=0.78). Eight percent (39mins) of objective TST was untreated among CMS-defined adherers, and 54.1% (216.8mins) of TST was untreated among CMS-defined non-adherers. When TST-on-treatment criteria were imposed (≥65%, ≥75%, and ≥85%, respectively), the percentage of untreated TST decreased among adherers, 5.2% (23 min), 4.3% (19 min), 0% (0 min) and among non-adherers, 42.8% (168 min), 41.2% (162 min), and 28.7% (118 min). From CMS to ≥85% of TST-on-treatment criteria, categorization as an adherer decreased from 89% (n=34) to 58% (n=22); non-adherer categorization increased from 5% (n=2) to 37% (n=14). Conclusion In the context of understanding biophysiological responses to PAP treatment, more sensitive and specific criteria for adherence and non-adherence is necessary. PAP use based on untreated TST is an opportunity to address this gap. Support The parent clinical trial was supported by NIH/NINR (R00NR011173; Sawyer PI)

0884 The Effect of Bariatric Surgery on Sleep Disordered Breathing in Adolescents and Young Adults

Abstract Introduction Childhood obesity is the major risk factor sleep disordered breathing (SDB). Severely obese young people may require bariatric surgery for correction of obesity, if other methods of weight loss have failed. We aim to assess the effect of bariatric surgery on SDB, in adolescents and young adults. Methods We conducted a retrospective chart review study of patients who underwent bariatric surgery between January 1, 2006 and August 31, 2019 at Cincinnati Children’s Hospital. Only patients who had pre-operative and post-operative polysomnograms were included in the study. Results Twenty-seven children and young adults (female: 59.2%) met the criteria for entry into analysis. The mean age of subjects at the time of weight loss surgery was 17.9 years (range: 12.9 to 32.5). Majority of the patients underwent laparoscopic partial gastrectomy (85.2%) and the remaining underwent laparoscopic gastric bypass surgery (14.8%). The average duration of follow up for post study measurements after the surgery was 10.4 months (Range: 0.4 to 57.5). The median Body Mass Index (BMI) was significantly lower at post-surgery (49.9 kg/m2[IQR: 45.4-55.9][pre] vs 39.3 kg/m2[IQR: 33.9-46][post], P&amp;lt;0.001). The median obstructive AHI was significantly reduced at post-surgery (6.7/hr[IQR: 3.1-16.4][pre] vs 2.6/hr[IQR: 1.6-6][post], P= 0.03). Median heart rate (HR) during REM (79 bpm[IQR:67-90][pre] vs 67 bpm[IQR: 59.7-72][post], P&amp;lt;0.0001) and NREM (81 bpm[IQR:65-91][pre] vs 65 bpm[IQR: 58-73][post], P&amp;lt;0.0001) sleep were significantly lower at post-surgery. There was no statistically significant difference in sleep architecture (sleep latency, arousal index and percentage of REM, N1 and N3 sleep, P&amp;gt; 0.05) except N2 sleep (53.1% [IQR:47.7-57.3] [pre] vs 55.7% [IQR:51.4-63.7] [post], P= 0.03) which was significantly increased at post-surgery. Conclusion There was significant improvement in BMI and SDB after weight loss surgery in children and young adults. Interestingly, there was a decrease in heart rate during both REM and NREM sleep after surgery which may suggest a decrease in sympathetic activation due to improvement if SDB. The sleep architecture remained unchanged after surgery, except the percentage of N2 sleep. Support Cincinnati Children’s Hospital Research Foundation

Obstructive Sleep Apnea Severity and the Risk of Occupational Injury: A Prospective Observational Cohort.

To determine whether patients with obstructive sleep apnea (OSA) are at increased risk of occupational injury (OI) METHODS: Working patients (aged 18 to 65 who reported more than 10h of work per week) who were referred to the University of British Columbia Sleep Laboratory for suspected OSA for polysomnogram (PSG) were recruited from 2003 to 2011. Patients completed an extensive survey the night of their PSG. Validated OI was obtained by linking patient data to Workers Compensation Board Claims Data. 1109 workers were studied; mean age was 47.1years, median AHI was 15.0/h, median BMI was 30kg/m2, 70.2% were male and 29% of patients worked in physical or manual related occupations. 78 patients (7.03%) suffered 140 OI in the 5years after PSG. In a multivariate logistic regression model, OSA severity [defined as a log(AHI + 1)] was a significant predictor of OI (p = 0.04) after controlling for age, sex, BMI, and physical or manual related occupations. Patients with moderate and severe OSA had approximately two times the odds of an OI compared to patients without OSA (OR 1.99, 95% CI 0.96-4.44 and 2.00, 95% CI 0.96-4.49 for moderate and severe OSA groups, respectively). In this prospective study, OSA severity was independently associated with an increased risk of OI.

Classification of Sleep Apnea Severity by Electrocardiogram Monitoring Using a Novel Wearable Device.

Sleep apnea (SA) is a prevalent disorder diagnosed by polysomnography (PSG) based on the number of apnea–hypopnea events per hour of sleep (apnea–hypopnea index, AHI). PSG is expensive and technically complex; therefore, its use is rather limited to the initial diagnostic phase and simpler devices are required for long-term follow-up. The validity of single-parameter wearable devices for the assessment of sleep apnea severity is still debated. In this context, a wearable electrocardiogram (ECG) acquisition system (ECG belt) was developed and its suitability for the classification of sleep apnea severity was investigated using heart rate variability analysis with or without data pre-filtering. Several classification algorithms were compared and support vector machine was preferred due to its simplicity and overall performance. Whole-night ECG signals from 241 patients with a suspicion of sleep apnea were recorded using both the ECG belt and patched ECG during PSG recordings. 65% of patients had an obstructive sleep apnea and the median AHI was 21 [IQR: 7–40] . The classification accuracy obtained from the ECG belt (accuracy: 72%, sensitivity: 70%, specificity: 74%) was comparable to the patched ECG (accuracy: 74%, sensitivity: 88%, specificity: 61%). The highest classification accuracy was obtained for the discrimination between individuals with no or mild SA vs. moderate to severe SA. In conclusion, the ECG belt provided signals comparable to patched ECG and could be used for the assessment of sleep apnea severity, especially during follow-up.

First Description of the Hyperpnea-Hypopnea Periodic Breathing in Patients with Interstitial Lung Disease-Obstructive Sleep Apnea: Treatment Implications in a Real-Life Setting.

There is evidence that hypopneas are more common than apneas in obstructive sleep apnea (OSA) related to idiopathic pulmonary fibrosis (IPF). We investigated the frequency distribution of hypopneas in 100 patients with interstitial lung diseases (ILDs) (mean age 69 yrs ± 7.8; 70% males), including 54 IPF cases, screened for OSA by home sleep testing. Fifty age- and sex-matched pure OSA patients were included as controls. In ILD-OSA patients the sleep breathing pattern was characterized by a high prevalence of hypopneas that were preceded by hyperpnea events configuring a sort of periodic pattern. This finding, we arbitrarily defined hyperpnea–hypopnea periodic breathing (HHPB), was likely reflecting a central event and was completely absent in control OSA. Also, the HHPB was highly responsive to oxygen but not to the continuous positive pressure support. Thirty-three ILD-OSA patients (42%) with a HHPB associated with a hypopnea/apnea ratio ≥3 had the best response to oxygen with a median residual AHI of 2.6 (1.8–5.6) vs. 28.3 (20.7–37.8) at baseline (p < 0.0001). ILD-OSA patients with these characteristics were similarly distributed in IPF (54.5%) and no-IPF cases (45.5%), the most of them being affected by moderate–severe OSA (p = 0.027). Future studies addressing the pathogenesis and therapy management of the HHPB should be encouraged in ILD-OSA patients.

Craniofacial, dental arch morphology, and characteristics in preschool children with mild obstructive sleep apnea

Background/purposePediatric obstructive sleep apnea (OSA) might be a serious cause of neurocognitive deficits, behavioral changes, and craniofacial disharmony in children at very young age with mild type of OSA. This study aims to examine the effect of mild OSA on craniofacial morphology as well as dental arch morphology and characteristics in preschool children. Materials and methodsThe test group comprised 16 preschool children (11 boys, 5 girls; mean age: 5.14 years old; mean AHI: 2.02) with confirmed polysomnographic diagnosis of mild OSA. Ten control subjects also underwent polysomnography (5 boys, 5 girls; mean age: 5.18 years old; median AHI: 0.43). Lateral cephalometric radiographs and dental arch impressions were obtained and measured. A survey on characteristics and quality of life (OSA-18) was filled out by study participants' caregivers. ResultsFor craniofacial morphology, a significant increase in ANB angle, a decrease in SNB angle, and larger overjet size were seen in the group with mild OSA, compared with the control group. More frequent sleep disturbances and mood swing were also found in children with mild OSA, based on the OSA-18 assessment. ConclusionPreschool children with mild OSA present the following: skeletal Class II pattern with a more retrognathic mandible, increased overjet size, and more pronounced symptoms in the domains of sleep and emotion. Dental arch constriction is not a typical feature in our sample of Asian preschool children with mild OSA.

New-generation positional therapy in patients with positional central sleep apnea.

To evaluate the effect of a sleep position trainer (SPT) in patients with positional central sleep apnea (PCSA). A multicentre cohort study was conducted. Patients with symptomatic PCSA were included. Effectiveness, compliance and quality of life were assessed at 1- and 6-month follow-up. Sixteen patients were included. Median AHI dropped from 23.4/h [12.9-31.2] to 11.5/h [7.2-24.5] (p = 0.044) after 1-month SPT therapy and in patients who continued treatment, median AHI further decreased after 6months to 9.7/h [3.4-27.6] (p = 0.075). Median percentage of supine sleep decreased significantly from 37.6 [17.2-51.8] to 6.7 [0.7-22.8] (p < 0.001), after 1month, and to 6.8 [0.7-22.1] (p = 0.001), after 6months. Mean compliance over 1 and 6months was 78.6 ± 35.3 and 66.0 ± 33.3%, respectively. Epworth Sleepiness Scale at baseline was 9.5 [3.3-11.8] and did not significantly decrease after 1month (11.0 [3.0-13.0]) and 6months (4.0 [3.0-10.5]) follow-up. Functional Outcomes of Sleep Questionnaire remained stable within the first month. However, after 6months, there was a significant improvement compared to baseline values, 15.9 [11.9-18.4] vs. 17.8 [14.3-19.2]; p = 0.030. This is the first study on effects of positional therapy with a new-generation smart device in patients with PCSA after 1 and 6months of follow-up. Results of this study show that the SPT is effective in reducing AHI and central AI, feasible in PCSA, and is associated with symptomatic improvement. While the working mechanism behind this effect remains speculative, the effect is positive and considerable.

Combination therapy with mandibular advancement and expiratory positive airway pressure valves reduces obstructive sleep apnea severity.

Mandibular advancement splint (MAS) therapy is a well-tolerated alternative to continuous positive airway pressure for obstructive sleep apnea (OSA). Other therapies, including nasal expiratory positive airway pressure (EPAP) valves, can also reduce OSA severity. However, >50% of patients have an incomplete or no therapeutic response with either therapy alone and thus remain at risk of adverse health outcomes. Combining these therapies may yield greater efficacy to provide a therapeutic solution for many incomplete/nonresponders to MAS therapy. Thus, this study evaluated the efficacy of combination therapy with MAS plus EPAP in incomplete/nonresponders to MAS alone. Twenty-two people with OSA (apnea-hypopnea index [AHI] = 22 [13, 42] events/hr), who were incomplete/nonresponders (residual AHI > 5 events/hr) on an initial split-night polysomnography with a novel MAS device containing an oral airway, completed an additional split-night polysomnography with MAS + oral EPAP valve and MAS + oral and nasal EPAP valves (order randomized). Compared with MAS alone, MAS + oral EPAP significantly reduced the median total AHI, with further reductions with the MAS + oral/nasal EPAP combination (15 [10, 34] vs. 10 [7, 21] vs. 7 [3, 13] events/hr, p < 0.01). Larger reductions occurred in supine nonrapid eye movement AHI with MAS + oral/nasal EPAP combination therapy (ΔAHI = 23 events/hr, p < 0.01). OSA resolved (AHI < 5 events/hr) with MAS + oral/nasal EPAP in nine individuals and 13 had ≥50% reduction in AHI from no MAS. However, sleep efficiency was lower with MAS + oral/nasal EPAP versus MAS alone or MAS + oral EPAP (78 ± 19 vs. 87 ± 10 and 88 ± 10% respectively, p < 0.05). Combination therapy with a novel MAS device and simple oral or oro-nasal EPAP valves reduces OSA severity to therapeutic levels for a substantial proportion of incomplete/nonresponders to MAS therapy alone. Name: Targeted combination therapy: Physiological mechanistic studies to inform treatment for obstructive sleep apnea (OSA)URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372279 Registration: ACTRN12617000492358 (Part C).

C-Reactive Protein Levels and the Risk of Incident Cardiovascular and Cerebrovascular Events in Patients with Obstructive Sleep Apnea.

Patients with obstructive sleep apnea (OSA) are at increased risk of cardiovascular and cerebrovascular disease (CVD) but it is unclear who are at greatest risk. We determined whether the inflammatory marker, C-reactive protein (CRP), could be a useful prognostic biomarker. Adult patients referred for polysomnography (PSG) with OSA were studied. Serum CRP levels were measured using ELISA the morning after PSG. Validated CV events within 4years of PSG were ascertained by linking to provincial research datasets. 155 patients with OSA (AHI ≥ 5/h) had CRP measured. Median age was 53 and median AHI was 21/h. 10 patients (7.1%) suffered at least one event, but rates varied substantially by CRP (0/35 patients in the lowest quartile, and 7/39 in the highest CRP quartile). In the unadjusted analysis, patients in the highest CRP quartile (≥ 2.38mg/L) were significantly more likely to suffer an event (odds ratio = 9.72 (95% CI 2.43-38.84), p = 0.001). CRP continued to be a significant predictor after controlling for multiple confounders. OSA severity and desaturation were not significantly associated with prospective events. In this small preliminary study, OSA patients with an elevated CRP were significantly more likely to suffer a CVD event in the 4years after PSG. Although these findings need to be confirmed in larger prospective cohorts, CRP may be useful in risk stratifying OSA patients to guide therapy or to identify patients that might be most appropriate for clinical trials of CVD prevention.

Robot-assisted Tongue Base Resection ensures favorable therapeutic outcome to Obstructive Sleep Apnea patients with Lingual tonsil hypertrophy

Tongue base (TB) narrowing is recognized as a significant site of upper airway collapse during sleep in obstructive sleep apnea (OSA) patients and robot technology is expected to have promising clinical utility in OSA patients with TB narrowing. The purpose of our study is to demonstrate the better therapeutic conditions and favorable indications of robot-assisted TB resection (TBR) in OSA. We performed robot-assisted TBR combined with nasal and palatal surgery in 16 OSA patients with any of the following characteristics: severe TB narrowing (over grade II) and moderate or severe OSA. The preoperative median AHI was 48.8/hr and the median lowest SaO2 was 82.0%. The median AHI decreased to 18.7/hr and ten patients (62.5%) were included in the responder group following robot-assisted TBR combined with nasal and palatal surgery. The lowest SaO2 improved to 90.5% and the posterior airway space (PAS) was significantly increased following robot-assisted TBR. Cephalometric results showed that wider PAS were observed in responders compared to non-responders prior to robot-assisted TBR. Interestingly, there was greater improvement in the objective parameters including PAS in the OSA patients with lingual tonsilar hypertrophy than they were in those without and all patients with lingual tonsillar hypertrophy (n = 6) responded to robot-assisted TBR. Robot-assisted TBR exhibited minimal morbidity and postoperative complications in OSA patients. Robot-assisted TBR can be considered a promising and innovative surgical option to reduce TB volume and improve sleep parameters in OSA patients with TB narrowing. OSA patient with TB narrowing due to lingual tonsil hypertrophy shows greater therapeutic outcome and lingual tonsil hypertrophy appears to be most favorable surgical indications of robot-assisted TBR.